JP7848559B2 - Joint locking mechanism and robotic device - Google Patents

Description

This disclosure relates to a joint locking mechanism for restricting or allowing relative rotation of two links connected via a joint, and to a robotic device equipped therewith.

Conventionally, a robot arm driven by supplying and discharging compressed air to an airbag-type pneumatic actuator is known (see, for example, Patent Document 1). This robot arm includes a pulley rotatably supported by a rocking frame member, a wire wound around the pulley, and two pneumatic actuators, each pin-connected to a fixed member of the rocking frame member and connected to the corresponding ends of the wire. Furthermore, the robot arm includes a brake drum coaxially fixed to the pulley, a brake shoe positioned opposite the outer circumferential surface of the brake drum, a lever arm with an elastic contraction body having the same configuration as the above-mentioned pneumatic actuator attached to one end and a tension spring attached to the other end, and a brake cam eccentrically mounted on an axis that rotates integrally with the lever arm to press the brake shoe. In such a robot arm, when compressed air is supplied to the elastic contraction body, the elastic contraction body rotates the lever arm against the contraction force of the tension spring, and the brake cam attached to the lever arm separates from the brake shoe. This causes the brake shoe to separate from the brake drum, allowing the pulley to rotate. Furthermore, by supplying compressed air to one pneumatic actuator and discharging it from the other, the pulley rotates, and the oscillating frame member rotates around the axis of the pulley as the pulley rotates. Additionally, when the oscillating frame member reaches the desired position, discharging compressed air from the elastic contraction body causes the contraction force of the tension spring to overcome the contraction force of the elastic contraction body, rotating the lever arm. Consequently, the brake cam presses the brake shoe against the brake drum. This restricts the rotation of the brake drum and pulley, and fixes the position of the oscillating frame member.

Furthermore, conventionally, a vehicle seat is known that includes a seat cushion that supports the buttocks of a seated person, a seat back that can tilt in the front-rear direction relative to the seat cushion, and a reclining device provided on the axis of rotation of the seat back's tilt to allow/prohibit the tilt of the seat back (see, for example, Patent Document 2). Such a seat reclining device includes a first member (ratchet) provided on the seat back side, a second member (base plate) provided on the seat cushion side, a pole, a guide formed on the second member, and first and second cams. The first member has internal teeth formed along the circumferential direction, and the second member is rotatable relative to the first member in the circumferential direction. The pole has external teeth that can mesh with the internal teeth of the first member and is movably supported by the second member. The guide on the second member guides the pole between a locked position where the internal and external teeth mesh and an unlocked position where the internal and external teeth do not mesh. The first cam (rotating cam) is provided between the first and second members and presses the pole in the direction of the locked position. The second cam, pressed by the first cam, presses the pole against the guide while also pressing it in the direction of the locked position. With this reclining device, the first and second cams smoothly engage the external teeth of the pole with the internal teeth of the first member, thereby restricting (locking) the tilting of the seat back relative to the seat cushion.

Special Publication No. 06-053353 Japanese Patent Publication No. 2012-200483

The joint locking mechanism (brake mechanism) for the robot arm described in Patent Document 1 requires a relatively large space for the arrangement of the brake drum, brake shoe, brake cam, lever arm, elastic contraction body, and tension spring. Therefore, if the brake mechanism described in Patent Document 1 is adopted, the entire robot arm will become large. Furthermore, in the robot arm described in Patent Document 1, for example, if the lock by the joint locking mechanism is released after the robot arm has been stopped and the oscillating frame member has been fixed (locked) by the joint locking mechanism, compressed air must be supplied to the elastic contraction body, making it difficult to carry out maintenance quickly due to the preparation of a compressed air supply source, etc. On the other hand, it is also conceivable to apply a joint locking mechanism that utilizes the reclining device described in Patent Document 2 to two links connected via a joint, instead of a joint locking mechanism including a brake drum and brake shoe. However, in the reclining device described in Patent Document 2, the maximum radius (effective radius) of the first cam (rotating cam) is relatively small, and it is necessary to apply a large rotational torque to the first cam in order to move the pole in the direction of the locked position. Furthermore, in the reclining device described in Patent Document 2, moving the pole from the unlocked position to the locked position requires rotating the first cam (rotating cam) by a relatively large angle. For example, if a linear actuator is used to rotate the first cam, the required stroke of the actuator becomes very large, necessitating a mechanism to convert the direction of the force. Therefore, even in a robot arm incorporating a joint locking mechanism based on the above reclining device, a large actuator is required to rotate the first cam, making it difficult to effectively suppress the increase in size of the joint locking mechanism and, consequently, the entire device. Moreover, even in the joint locking mechanism based on the above reclining device, operating the actuator is necessary to move the pole from the locked position to the unlocked position, requiring considerable effort to release the lock by the joint locking mechanism for maintenance purposes.

Therefore, the primary objective of this disclosure is to provide a compact joint locking mechanism and a robotic device equipped therewith that smoothly and effectively restrict or allow the relative rotation of two links connected via a joint, and that easily release the restriction on the relative rotation of the two links.

The joint locking mechanism of this disclosure is a joint locking mechanism that receives fluid from a fluid supply device and restricts or allows the relative rotation of two links connected via a joint depending on the fluid supply state by the fluid supply device, comprising: a first member fixed to one of the two links; a second member fixed to the other of the two links so as to be rotatable relative to the first member around the joint axis of the joint; a plurality of internal teeth provided on the first member; a slider supported by the second member so as to be movable in a first direction; a pole having a plurality of external teeth that can mesh with the plurality of internal teeth of the first member and supported by the second member so as to move toward and away from the plurality of internal teeth along a second direction intersecting the first direction; and The system includes: a connecting member rotatably connected to the slider and the pole, which moves the pole in a second direction in response to the slider's movement in a first direction; a biasing member positioned between the second member and the slider, which biases the slider to one side in the first direction so that the pole's multiple external teeth engage with the pole's multiple internal teeth; an unlocking actuator that moves the slider to the other side in the first direction against the biasing force of the biasing member in response to the supply of fluid from the fluid supply device; and a manual unlocking mechanism having a manually operated lever, which moves the slider to the other side in the first direction against the biasing force of the biasing member in response to the operation of the lever.

In the joint locking mechanism of this disclosure, when fluid is not supplied from the fluid supply device to the unlock actuator, the slider is biased to one side in the first direction by the biasing member, and the multiple external teeth of the pole engage with the multiple internal teeth provided on the first member. As a result, the first member, slider, pole, and second member are integrated, and the relative rotation of the two links is restricted. Conversely, when fluid is supplied from the fluid supply device to the unlock actuator, the unlock actuator moves the slider to the other side in the first direction against the biasing force of the biasing member. As a result, the engagement between the multiple external teeth and the multiple internal teeth of the pole is released, and the relative rotation of the first member and the second member, i.e., the two links, is permitted. Thus, in the joint locking mechanism of this disclosure, the relative rotation of the two links can be smoothly and effectively restricted or permitted by moving the slider to one side or the other side in the first direction by the biasing member or the unlock actuator. Furthermore, the stroke required for the unlock actuator is significantly smaller compared to a joint lock mechanism that uses a rotating cam to engage multiple external teeth of a pole supported by a second member with multiple internal teeth on the first member side. Therefore, it is possible to miniaturize the unlock actuator and thus the entire joint lock mechanism. Moreover, when the slider is biased to one side in the first direction by a biasing member, restricting the relative rotation of the two links, manually operating the lever of the manual unlock mechanism allows the slider to move to the other side in the first direction against the biasing force of the biasing member, thereby allowing the relative rotation of the two links. This makes it possible to easily release the restriction on the relative rotation of the two links by the joint lock mechanism during maintenance, etc., without supplying fluid from a fluid supply device to the joint lock mechanism. Therefore, the joint lock mechanism of this disclosure allows for a compact overall device while smoothly and effectively restricting or allowing the relative rotation of two links connected via a joint, and easily releasing the restriction on the relative rotation of the two links.

This is a schematic diagram showing the robotic device of this disclosure. This is a cross-sectional view showing a fluid actuator of a robotic device in this disclosure. This is a partial cross-sectional view showing the joint locking mechanism of a robotic device in this disclosure. This is a schematic diagram showing the joint locking mechanism of the robot device disclosed herein. This diagram shows the fluid supply system for the robotic device disclosed herein. This diagram shows the fluid supply system for the robotic device disclosed herein. This is a partial cross-sectional view showing an outflow control valve included in the fluid supply device of a robotic apparatus of the present disclosure. This diagram illustrates the operation of the joint locking mechanism and fluid supply device of the robotic apparatus disclosed herein. This is a partial cross-sectional view illustrating the operation of the joint locking mechanism of the robotic apparatus of the present disclosure. This diagram illustrates the operation of the joint locking mechanism and fluid supply device of the robotic apparatus disclosed herein. This diagram illustrates the operation of the joint locking mechanism and fluid supply device of the robotic apparatus disclosed herein. This diagram illustrates the operation of the joint locking mechanism and fluid supply device of the robotic apparatus disclosed herein. This is a time chart illustrating the operating states of the joint locking mechanism and fluid supply device of the robot apparatus described herein. This is a schematic diagram illustrating the operation of the joint locking mechanism of the robot device disclosed herein.

Next, embodiments for carrying out the invention of this disclosure will be described with reference to the drawings.

Figure 1 is a schematic diagram showing the robot device 1 of the present disclosure. The robot device 1 shown in the figure includes a robot arm (robot body) 2 and a fluid supply device (liquid supply device) 10 that supplies and discharges hydraulic fluid (fluid) to a plurality (two in this embodiment) of double-acting cylinders (fluid cylinders) 3 which act as fluid actuators to operate the robot arm 2. In this embodiment, the robot device 1 is mounted on a transport cart which is an automated guided vehicle (AGV) or autonomous mobile robot (AMR) capable of self-propelling to a designated target location, or it is used by being fixed in a predetermined installation location. As shown in Figure 1, the robot arm 2 is a multi-joint arm that includes, in addition to multiple double-acting cylinders 3, a support member (bracket) 4, multiple arms (links) 5a, 5b, 5c, links 6a, 6b, 6c, 6d that form first and second parallel link mechanisms through the cooperation of the multiple arms 5a, 5b, 5c, a hand section (robot hand) 7 as a gripping section (endpiece), and multiple (three in this embodiment) joints (pin joints) Ja, Jb, Jc.

Each double-acting cylinder 3 of the robot arm 2 includes, as shown in Figure 2, a cylinder (cylinder tube) 30, a piston 34 slidably arranged axially within the cylinder 30, and a piston rod 35 fixed coaxially to the piston 34. Furthermore, each double-acting cylinder 3 includes a first fluid chamber (extension-side fluid chamber) 31 defined on one side (right side in Figure 2) of the piston 34 within the cylinder 30, and a second fluid chamber (retraction-side fluid chamber) 32 defined on the other side (left side in Figure 2) of the piston 34 within the cylinder 30. By supplying hydraulic fluid to the first fluid chamber 31 and discharging hydraulic fluid from the second fluid chamber 32 using the fluid supply device 10, the piston 34 and piston rod 35 can be moved to the left side in Figure 2 relative to the cylinder 30, thereby extending the double-acting cylinder 3 as a double-acting actuator. Furthermore, by supplying hydraulic fluid to the second fluid chamber 32 and discharging hydraulic fluid from the first fluid chamber 31 using the fluid supply device 10, the piston 34 and piston rod 35 can be moved to the right side of the cylinder 30 in Figure 2, thereby retracting the double-acting cylinder 3.

As shown in Figure 1, the arm 5a of the robot arm 2 is rotatably connected to the support member 4 as a link via joint Ja, and in this embodiment, it rotates relative to the support member 4 by the extension and retraction of a single double-acting cylinder 3. One end (the end of the piston rod) of the double-acting cylinder 3 corresponding to the support member 4 and arm 5a, i.e., joint Ja, is rotatably connected to a lever member fixed to the support member 4, and the other end (the end of the cylinder) is rotatably connected to the tip of arm 5a (the end on the arm 5b side). Also, arm 5b is rotatably connected to arm 5a via joint Jb, and in this embodiment, it rotates relative to arm 5a by the extension and retraction of a single double-acting cylinder 3. One end (the end of the piston rod) of the double-acting cylinder 3 corresponding to arms 5a and 5b, i.e., joint Jb, is rotatably connected to the base end (the end on the support member 4 side) of arm 5a, and the other end (the end of the cylinder) is rotatably connected to a lever member fixed to the base end (the end on the arm 5a side) of arm 5b. Furthermore, arm 5c is rotatably connected to the tip of arm 5b via joint Jc. However, multiple double-acting cylinders 3 may be provided parallel to the support member 4 and arm 5a, or multiple double-acting cylinders 3 may be provided parallel to arms 5a and 5b.

Link 6a is fixed to the support member 4, and the base end of link 6b is rotatably connected to the tip of arm 5a and the base end of arm 5b via joint Jb. Link 6c has the same link length as arm 5a and is rotatably connected to the free end (pivot portion) of link 6a, and is also rotatably connected to link 6b at a position separated from joint Jb by a length equivalent to the link length of link 6a. This constitutes a first parallel link mechanism in which arm 5a is the fixed link, link 6a is the driving link, link 6b is the driven link, and link 6c is the intermediate link. Furthermore, link 6d is rotatably connected to arm 5c at a position separated from joint Jc by a predetermined length, and is also rotatably connected to link 6b at a position separated from joint Jb by the same predetermined length. This results in a second parallel link mechanism in which arm 5b is a fixed link, link 6b is a driving link, arm 5c is a driven link, and link 6d is an intermediate link. Through the action of these first and second parallel link mechanisms, arm 5c is always maintained parallel to the travel surface of the transport trolley or the mounting surface of the robot device 1, regardless of the rotation angles of arms 5a and 5b.

The hand portion 7 of the robot arm 2 is attached to the end-effector arm 5c and is controlled by the control device 100 of the robot device 1 to grasp the target object (hereinafter referred to as "grasping target"). The fluid supply device 10 is also controlled by the control device 100 to supply and discharge hydraulic fluid to each double-acting cylinder 3. This allows the robot arm 2 to be driven by hydraulic pressure (fluid pressure) to move the hand portion 7 to the desired position. However, the fluid supply device 10 may supply and discharge a liquid other than hydraulic fluid, such as water, to each double-acting cylinder 3, or it may supply and discharge a gas, such as compressed air, to each double-acting cylinder 3.

The joints Ja and Jb of the robot arm 2 each include a joint axis Ax (see Figure 1) and a bearing (not shown) that rotatably supports the joint axis Ax. In this embodiment, one end of the joint axis Ax of joint Ja is fixed (connected) to the arm 5a corresponding to joint Ja via a spline fitting portion, and the other end of the joint axis Ax protrudes from the inner race of the bearing held by the support member 4 on the side opposite to the arm 5a. Similarly, one end of the joint axis Ax of joint Jb is fixed (connected) to the arm 5a corresponding to joint Jb via a spline fitting portion, and the other end of the joint axis Ax protrudes from the inner race of the bearing held by the arm 5b on the side opposite to the arm 5a. Furthermore, as shown in Figure 1, the robot device 1 includes a plurality (two in this embodiment) of joint locking mechanisms 8 provided for each joint Ja and Jb. Each joint locking mechanism 8 receives hydraulic fluid from the fluid supply device 10 and, depending on the hydraulic fluid supply status from the fluid supply device 10, restricts or allows the relative rotation of the support member 4 and arm 5a connected via joint Ja, or the relative rotation of arms 5a and 5b connected via joint Jb.

Figure 3 is a partial cross-sectional view showing the joint locking mechanism 8 of the robot device 1. As shown in the figure, the joint locking mechanism 8 includes a bracket (first member) 81 and an actuator block (second member) 82, both made of metal or the like. In the joint locking mechanism 8 corresponding to joint Ja, the bracket 81 is fixed to the support member 4, and the actuator block 82 is fixed to the arm 5a via the joint axis Ax. In the joint locking mechanism 8 corresponding to joint Jb, the bracket 81 is fixed to the arm 5b, and the actuator block 82 is fixed to the arm 5a via the joint axis Ax.

The bracket 81 includes a short cylindrical tubular portion 81c and a plurality of fastening portions 81f that project radially outward (radially) at circumferential intervals from one end of the tubular portion 81c in the axial direction. Each fastening portion 81f has a bolt hole through which a bolt (not shown) is inserted. The bracket 81 is fixed (fastened) to the support member 4 or arm 5b via a plurality of bolts inserted through the bolt holes of the corresponding fastening portions 81f, so that the tubular portion 81c coaxially surrounds the end of the joint axis Ax that protrudes from the bearing of the joint Ja or Jb. A ring gear 810 having a plurality of internal teeth 810t formed over the entire circumference of its inner part is fixed to the bracket 81. In this embodiment, the ring gear 810 is spline-fitted to the inner circumference of the tubular portion 81c of the bracket 81 and is fixed (prevents coming off) to the tubular portion 81c via a plurality of bolts 811. Furthermore, the bolt holes in each fastening portion 81f may be formed in an elongated shape.

The actuator block 82 is fixed to the arm 5a by spline fitting onto the joint axis Ax, which protrudes from a bearing held by the support member 4 or arm 5b. This allows the actuator block 82 to rotate around the joint axis Ax relative to the bracket 81. The actuator block 82 also includes a plurality of first guide portions 82x (for example, four in this embodiment) extending parallel to each other along a predetermined x-direction (first direction, left-right direction in Figure 3) on either the upper or lower side of the joint axis Ax in Figure 3, and a plurality of second guide portions 82y (for example, four in this embodiment) extending in a y-direction (second direction, up-down direction in Figure 3) perpendicular to the x-direction.

Multiple first guide sections 82x are arranged in pairs on the upper and lower sides of the joint axis Ax in Figure 3. That is, the two upper first guide sections 82x and the two lower first guide sections 82x in Figure 3 are arranged symmetrically with respect to an axis that extends in the x-direction through the center of the joint axis Ax. Furthermore, the uppermost first guide section 82x in Figure 3 extends in the x-direction on the joint axis Ax side and has a guide surface perpendicular to the plane of Figure 3. In addition, the first guide section 82x on the upper side of Figure 3 that is close to the joint axis Ax has a guide surface that faces the guide surface of the uppermost first guide section 82x at a certain distance in the y-direction. Furthermore, the lowermost first guide section 82x in Figure 3 extends in the x-direction on the joint axis Ax side and has a guide surface perpendicular to the plane of Figure 3. Furthermore, the first guide portion 82x located at the bottom of Figure 3, close to the joint axis Ax, has a guide surface that faces the guide surface of the lowest first guide portion 82x at a certain distance in the y-direction.

Multiple second guide sections 82y are arranged in pairs on the upper and lower sides of the joint axis Ax in Figure 3, facing each other at a fixed distance in the x-direction. That is, the two upper second guide sections 82y and the two lower second guide sections 82y in Figure 3 are arranged symmetrically with respect to an axis extending in the x-direction through the center of the joint axis Ax. Furthermore, the two upper second guide sections 82y in Figure 3 are arranged symmetrically with respect to an axis extending in the y-direction through the center of the joint axis Ax, and the two lower second guide sections 82y in Figure 3 are arranged symmetrically with respect to an axis extending in the y-direction through the center of the joint axis Ax. Furthermore, one of the two upper second guide portions 82y in Figure 3 extends in the y-direction on the side of the other second guide portion 82y and has a guide surface perpendicular to the plane of Figure 3. The other of the two upper second guide portions 82y in Figure 3 extends in the y-direction on the side of the aforementioned second guide portion 82y and has a guide surface perpendicular to the plane of Figure 3. Additionally, one of the two lower second guide portions 82y in Figure 3 extends in the y-direction on the side of the other second guide portion 82y and has a guide surface perpendicular to the plane of Figure 3. The other of the two lower second guide portions 82y in Figure 3 extends in the y-direction on the side of the aforementioned second guide portion 82y and has a guide surface perpendicular to the plane of Figure 3.

Furthermore, a stopper portion 82st is formed in the y-direction between one of the two upper second guide portions 82y in Figure 3 (for example, the left second guide portion 82y) and one end of the uppermost first guide portion 82x in Figure 3 in the x-direction (for example, the left end). Additionally, a stopper portion 82st is formed in the y-direction between the other of the two upper second guide portions 82y in Figure 3 (for example, the right second guide portion 82y) and the other end of the uppermost first guide portion 82x in Figure 3 in the x-direction (for example, the right end). Furthermore, a stopper portion 82st is formed in the y-direction between one of the two lower second guide portions 82y in Figure 3 (for example, the left second guide portion 82y) and one end of the lowermost first guide portion 82x in Figure 3 in the x-direction (for example, the left end). Furthermore, a stopper portion 82st is formed in the y-direction between the other of the two lower second guide portions 82y in Figure 3 (for example, the rightmost second guide portion 82y) and the other end in the x-direction of the lowest first guide portion 82x in Figure 3 (for example, the rightmost end).

In addition, the actuator block 82 has a spring support hole 82s and a cylinder hole 82c. The spring support hole 82s is a circular hole that extends in the x-direction on one side of the joint axis Ax in the x-direction (left side in Figure 3) and opens at the end opposite to the joint axis Ax (left end in Figure 3). The cylinder hole 82c is a circular hole that extends in the x-direction on the other side of the joint axis Ax in the x-direction (right side in Figure 3) and opens at the end opposite to the joint axis Ax (right end in Figure 3). Furthermore, the actuator block 82 has an annular fluid passage 82p that surrounds the joint axis Ax and a small-diameter fluid hole 82h that connects the fluid passage 82p to the inside of the cylinder hole 82c. In this embodiment, the articulated axis Ax is formed hollow and has two fluid holes Ah, each extending coaxially with the cylinder bore 82c in the x-direction. The fluid passage 82p surrounds the two fluid holes Ah of the articulated axis Ax. The fluid hole 82h is a circular hole with a diameter significantly smaller than the inner diameter of the cylinder bore 82c, extending coaxially with the cylinder bore 82c in the x-direction, and functions as an orifice (restriction).

As shown in Figure 3, the actuator block 82 described above supports the slider 83 so as to be movable in the x-direction, and also supports the two poles 84 so as to be movable in the y-direction. The slider 83 is a frame-shaped member having an elongated opening 83o, and is slidably fitted (arranged) between the two upper first guide portions 82x of the actuator block 82 in the y-direction and between the two lower first guide portions 82x of the actuator block 82 in the y-direction in Figure 3. That is, the two inner surfaces of the slider 83 that extend in the x-direction and define the opening 83o are slidably supported in the x-direction by the corresponding guide surface of the two first guide portions 82x that are close to the joint axis Ax of the actuator block 82. In addition, the two outer surfaces of the slider 83 that extend in the x-direction are slidably supported in the x-direction by the guide surface of the uppermost or lowerest first guide portion 82x of the actuator block 82 in Figure 3. Furthermore, the slider 83 has a plurality of stopper contact portions 83a (for example, four in this embodiment) formed to face the corresponding stopper portion 82st of the actuator block 82 in the x-direction.

Each pole 84, supported by the actuator block 82, has a width slightly smaller than the distance between two paired second guide portions 82y (guide surfaces), and is slidably fitted (arranged) between the two corresponding second guide portions 82y in the x-direction. That is, the two poles 84 are supported by the actuator block 82 at 180° intervals so that they can move freely in the y-direction, and can move toward and away from the ring gear 810, which is provided on the bracket 81, on the radially inner side of the ring gear 810. Furthermore, the outer circumferential surface of each pole 84 has multiple external teeth 84t formed thereon, which can mesh with some of the multiple internal teeth 810t of the ring gear 810. The multiple external teeth 84t may be integrally molded with the pole 84, or a gear member manufactured separately from the pole 84 may be fixed to the pole 84.

As shown in Figure 3, one end of a connecting member 85 is rotatably connected to each pole 84 via a connecting pin on an axis extending in the y-direction through the center of the joint axis Ax, and the other end of the connecting member 85 is rotatably connected to the slider 83 via a connecting pin. Thus, the actuator block 82, slider 83, two poles 84, and two connecting members 85 form a double slider mechanism (fixed double slider crank mechanism), and each connecting member 85 moves the corresponding pole 84 closer to or further away from the ring gear 810 (multiple internal teeth 810t) along the y-direction in accordance with the movement of the slider 83 in the x-direction. Note that the slider 83 may be arranged one on each side in the axial direction of the joint axis Ax of the actuator block 82, and each pole 84 may be connected to the slider 83 via two connecting members 85, one on each side in the axial direction of the joint axis Ax of the actuator block 82.

Furthermore, in this embodiment, when both connecting members 85 extend in the y-direction and both slider mechanisms are at their dead centers, as shown in Figure 3, the multiple external teeth 84t of each pole 84 engage with some of the multiple internal teeth 810t of the ring gear 810 provided on the bracket 81. Also, when both slider mechanisms are at their dead centers, as shown in Figure 3, a gap is formed between the two stopper contact portions 83a on one side (left side in Figure 3) of the slider 83 in the x-direction and the corresponding stopper portion 82st of the actuator block 82, and the two stopper contact portions 83a on the other side (right side in Figure 3) of the slider 83 in the x-direction contact with the corresponding stopper portion 82st of the actuator block 82.

A coil spring 86, acting as a biasing member (elastic body), is positioned within the spring support hole 82s of the actuator block 82. One end of the coil spring 86 (the left end in Figure 3) abuts against a spring seat (contact member) 830 fixed to the slider 83 (one inner surface defining the opening 83o), and the other end of the coil spring 86 abuts against the wall on the joint axis Ax side that defines the spring support hole 82s. In this embodiment, the coil spring 86 is compressed between the actuator block 82 (the wall on the joint axis Ax side) and the slider 83 (spring seat 830) when both slider mechanisms are at their dead centers. As a result, in the state shown in Figure 3, the slider 83 is biased to one side in the x-direction (left side in Figure 3) by the coil spring 86 via the spring seat 830, and the two stopper contact portions 83a on the other side of the slider 83 in the x-direction (right side in Figure 3) contact the corresponding stopper portion 82st of the actuator block 82. This ensures that the multiple external teeth 84t of each pole 84 mesh well with the multiple internal teeth 810t of the ring gear 810. Consequently, the relative rotation between the bracket 81 holding the ring gear 810 and the actuator block 82 supporting each pole 84, i.e., the relative rotation between the support member 4 and the arm 5a, and the relative rotation of the arms 5a and 5b, is firmly restricted (locked). Note that instead of the coil spring 86, an elastic material such as a disc spring or rubber may be used as the biasing member.

Furthermore, a piston 87 is slidably positioned within the cylinder bore 82c of the actuator block 82. The tip surface of the piston 87 (the right end surface in Figure 3) abuts against a part of the slider 83 (the other inner surface that defines the opening 83o) when both slider mechanisms are at their dead centers, as shown in Figure 3. In addition, a sealing member such as an O-ring, a wear ring, or a scraper is positioned between the inner circumferential surface of the cylinder bore 82c and the outer circumferential surface of the piston 87. On one side of the piston 87 in the x-direction, i.e., the joint axis Ax side, an unlock fluid chamber 88 is defined by the inner circumferential surface of the cylinder bore 82c and the end surface of the piston 87 on the joint axis Ax side. The unlock fluid chamber 88 communicates with the interior of the joint axis Ax via the fluid bore 82h and fluid passage 82p of the actuator block 82 and the two fluid bore Ah of the joint axis Ax. In this embodiment, hydraulic fluid from the fluid supply device 10 is supplied to the unlock fluid chamber 88 via the inside of the articulation axis Ax, two fluid holes Ah, a fluid passage 82p, and a fluid hole 82h. The actuator block 82, including the cylinder hole 82c, and the piston 87 constitute a hydraulic unlock actuator FA that includes the unlock fluid chamber 88.

As shown in Figure 3, with the multiple external teeth 84t of each pole 84 meshed with the multiple internal teeth 810t of the ring gear 810, when hydraulic fluid as working fluid from the fluid supply device 10 is supplied to the unlock fluid chamber 88 via the inside of the articulation axis Ax, two fluid holes Ah, an annular fluid passage 82p, and a fluid hole 82h that functions as an orifice, the piston 87 moves to the other side in the x direction (right side in Figure 3), causing the slider 83 to move to the other side in the x direction against the biasing force of the coil spring 86. As a result, each pole 84 is pulled by the corresponding connecting member 85 and moves inward along the y direction (towards the articulation axis Ax), and the meshing between the multiple external teeth 84t of each pole 84 and the multiple internal teeth 810t of the ring gear 810 is released. As a result, relative rotation between the bracket 81 that holds the ring gear 810 and the actuator block 82 that supports each pole 84, that is, relative rotation between the support member 4 and the arm 5a, and relative rotation between the arms 5a and 5b, are permitted.

Furthermore, as shown in Figure 4, the joint locking mechanism 8 includes a manual release mechanism 90 that allows manual disengagement of the engagement between the multiple external teeth 84t of each pawl 84 and the multiple internal teeth 810t of the ring gear 810. In this embodiment, a cover 89 is fixed to the actuator block 82 of the joint locking mechanism 8 via multiple bolts 891, and the manual release mechanism 90 is attached to the cover 89 so that it can be operated from the outside. The manual release mechanism 90 has a manually operated lever 91, and in response to the operation of the lever 91, it moves the spring seat 830 fixed to the slider 83 to the other side in the first direction (right side in Figure 4), and also amplifies the force applied to the lever 91 (operating force due to the operation of the lever 91) and transmits it to the spring seat 830.

In this embodiment, the manual lock release mechanism 90 is composed of a four-bar linkage mechanism including a lever 91 as a first link, second and third links 92 and 93, and a cover 89 and actuator block 82 as fixed links. The lever 91 is rotatably supported by the cover 89 via a stepped bolt 901 that is screwed into the cover 89, and a knurled bolt 910 that functions as a knob is screwed into one end of the lever 91 (the operating end). The other end of the lever 91 (the non-operating end) is rotatably connected to one end of the second link 92 via a connecting pin 902. The third link 93 is rotatably supported by the cover 89 via a stepped bolt 903 that is screwed into the cover 89, and one end of the third link 93 is rotatably connected to the other end of the second link 92 (the end opposite to the lever 91 side) via a connecting pin 904. Furthermore, a pressing member 95 is fixed to the end of the third link 93 opposite to the second link 92, which presses against the spring seat 830 fixed to the slider 83, thereby moving the spring seat 830 to the other side in the first direction.

Furthermore, the lever 91 is rotatably supported by the cover 89 via a stepped bolt 901 at a position closer to the end on the second link 92 side (the non-operating end) than to the end on the knurled bolt 910 side (the operating end). In addition, the third link 93 is rotatably supported by a stepped bolt 903, i.e., the actuator block 82, midway between the end on the second link 92 side and the end on the pressing member 95, i.e., the spring seat 830 side. In this embodiment, the range from the portion of the lever 91 supported by the stepped bolt 901 to the end on the knurled bolt 910 side is curved so as to approach the joint axis Ax (encircle the joint axis Ax) with respect to the straight line connecting the axis of the stepped bolt 901 and the axis of the connecting pin 902. Furthermore, in this embodiment, the portion of the third link 93 supported by the stepped bolt 903, from the end on the pressing member 95 side, is bent so as to be close to the joint axis Ax with respect to the straight line connecting the axis of the stepped bolt 903 and the axis of the connecting pin 904.

Figures 5 and 6 are system diagrams showing the fluid supply device 10 of the robot device 1, which supplies hydraulic fluid as working fluid to each double-acting cylinder 3 and each joint locking mechanism 8. As shown in Figure 5, the fluid supply device 10 includes a tank 11 defining a hydraulic fluid reservoir (fluid reservoir), a pump 13 as a fluid supply source, a valve body VB, a relief valve (pressure control valve) RV, a check valve CV, and an accumulator 14. Furthermore, the fluid supply device 10 includes a plurality of linear solenoid valves 151, 152, 153, and 154 as fluid adjustment valves (fluid adjustment units), a first solenoid valve 16, a second solenoid valve 17, a shuttle valve 18 having first and second input ports 18ia, 18ib and an output port 18o, and a plurality of on/off valves (outflow control valves) 191, 192, 193, and 194.

Pump 13 is an electric pump controlled by the control device 100, which sucks in the hydraulic fluid stored in the tank 11 and discharges (pressure-feeds) it from the discharge port. In this embodiment, pump 13 includes a pump section including an impeller, etc., and a drive unit 130 having an electric motor, a reduction gear mechanism, a drive circuit such as an inverter controlled by the control device 100. The relief valve RV limits the pressure of the hydraulic fluid discharged by pump 13 so as not to exceed a predetermined upper limit pressure Plim (upper limit, in this embodiment, for example, about 6-7 MPa). The check valve CV allows the hydraulic fluid from the pump 13 (and relief valve RV) side to flow out into the fluid supply passage LL, and also restricts the flow of hydraulic fluid from the fluid supply passage LL side to the pump 13 (and relief valve RV) side. The accumulator 14 has an inlet and outlet for hydraulic fluid connected (directly connected) to the fluid supply passage LL downstream of the check valve CV, and stores the hydraulic pressure from the pump 13 side. The accumulator 14 used has a maximum operating pressure equal to or greater than the upper limit pressure Plim. Furthermore, a source pressure sensor PS is installed in the fluid supply passage LL downstream of the check valve CV and upstream of the accumulator 14 to detect the hydraulic fluid pressure in the fluid supply passage LL, i.e., the source pressure, i.e., the line pressure PL.

The linear solenoid valves 151-154 share a common configuration and are each positioned within the valve body VB and controlled by the control device 100. As shown in Figure 5, the linear solenoid valve (first pressure regulating valve) 151 adjusts the hydraulic pressure (driving pressure) to the first fluid chamber 31 of the double-acting cylinder 3 corresponding to joint Ja (support member 4 and arm 5a). The linear solenoid valve (second pressure regulating valve) 152 adjusts the hydraulic pressure to the second fluid chamber 32 of the double-acting cylinder 3 corresponding to joint Ja. The linear solenoid valve (first pressure regulating valve) 153 adjusts the hydraulic pressure to the first fluid chamber 31 of the double-acting cylinder 3 corresponding to joint Jb (arms 5a, 5b). The linear solenoid valve (second pressure regulating valve) 154 adjusts the hydraulic pressure to the second fluid chamber 32 of the double-acting cylinder 3 corresponding to joint Jb. In other words, linear solenoid valves 151-154 are provided for each of the first and second fluid chambers 31 and 32 of the multiple double-acting cylinders 3.

As shown in Figure 6, the linear solenoid valves 151-154 include an electromagnetic unit 15e whose energization is controlled by the control device 100, a spool 15s that is axially movable within a sleeve held by the valve body VB, and a spring 15sp that biases the spool 15s toward the electromagnetic unit 15e (upper side in Figure 6). Furthermore, the linear solenoid valves 151-154 include an input port 15i, an output port 15o, a feedback port 15f communicating with the output port 15o, and a drain port 15d that can communicate with the input port 15i and the output port 15o. The input port 15i of the linear solenoid valves 151-154 communicates with the fluid supply passage LL downstream of the accumulator 14. The drain port 15d of the linear solenoid valves 151-154 communicates with the tank 11 (hydraulic oil storage section) via the fluid return passage LD.

In this embodiment, the linear solenoid valves 151-154 are normally closed valves, and the spool 15s, when no current is supplied to the electromagnetic part 15e and is not energized, blocks communication between the input port 15i and the output port 15o by the biasing force of the spring 15sp, while opening communication between the output port 15o and the drain port 15d. The electromagnetic part 15e of the linear solenoid valves 151-154 moves the spool 15s axially against the biasing force of the spring 15sp to open communication between the input port 15i and the output port 15o in accordance with the applied current. This balances the thrust generated by power supply to the electromagnetic unit 15e (coil), the biasing force of the spring 15sp, and the thrust acting on the spool 15s towards the electromagnetic unit 15e due to the hydraulic pressure (drive pressure) supplied from the output port 15o to the feedback port 15f. This makes it possible to adjust the hydraulic fluid from the pump 13 (and relief valve RV) supplied to the input port 15i to the desired pressure and discharge it from the output port 15o. Furthermore, by feeding back the hydraulic pressure (drive pressure) supplied to the first or second fluid chambers 31, 32 of each double-acting cylinder 3 to the linear solenoid valves 151-154, when an external force other than the double-acting cylinder 3 is applied to the robot arm 2 driven by the double-acting cylinder 3, fluctuations in hydraulic pressure corresponding to the volume change of the first and second fluid chambers 31, 32 due to the external force can be absorbed. In addition, after the external force has disappeared, it is possible to quickly supply the required hydraulic pressure (drive pressure) to the first or second fluid chambers 31, 32 of each double-acting cylinder 3.

The first solenoid valve 16 is a normally open on/off solenoid valve and, as shown in Figure 6, includes an electromagnetic unit 16e whose energization is controlled by a control device 100, a spool 16s that is axially movable within a sleeve held by a valve body VB, and a spring 16sp that biases the spool 16s toward the electromagnetic unit 16e (upper side in Figure 6). Furthermore, the first solenoid valve 16 includes an input port 16i communicating with the fluid supply passage LL downstream of the accumulator 14, an output port 16o communicating with the first input port 18ia of the shuttle valve 18 via a fluid passage La formed in the valve body VB, and a drain port 16d.

When the first solenoid valve 16 is not energized and no current is supplied to the electromagnetic part 16e, the spool 16s of the first solenoid valve 16, as shown in Figure 6, connects the input port 16i and the output port 16o, while blocking the connection between the output port 16o and the drain port 16d, due to the biasing force of the spring 16sp. Hereinafter, the state in which the spool 16s connects the input port 16i and the output port 16o, while blocking the connection between the output port 16o and the drain port 16d, will be referred to as the "output state" of the first solenoid valve 16. When the first solenoid valve 16 is in this output state, it outputs hydraulic pressure, or line pressure PL, by causing the hydraulic fluid supplied from the fluid supply passage LL to the input port 16i to flow out through the output port 16o. Furthermore, when current is supplied to the electromagnetic part 16e, the spool 16s of the first solenoid valve 16, due to the thrust from the electromagnetic part 16e, opposes the biasing force of the spring 16sp, blocking communication between the input port 16i and the output port 16o, while simultaneously opening communication between the output port 16o and the drain port 16d. Hereinafter, the state in which the spool 16s blocks communication between the input port 16i and the output port 16o, while opening communication between the output port 16o and the drain port 16d, is referred to as the "non-output state" of the first solenoid valve 16.

As shown in Figures 5 and 6, the second solenoid valve 17 supplies and discharges hydraulic fluid to the joint locking mechanism 8 provided at the joints Ja and Jb of the robot arm 2. The second solenoid valve 17 is an electromagnetic spool valve and includes a sleeve disposed within the valve body VB, an electromagnetic unit 17e controlled by the control device 100, a spool 17s slidably disposed within the sleeve, and a spring 17sp that biases the spool 17s toward the electromagnetic unit 17e (upper side in Figure 6). Furthermore, the second solenoid valve 17 includes an input port (fluid input port) 17i, a first output port 17oa, a second output port 17ob (different from the first output port 17oa), a first drain port 17da, and a second drain port 17db.

As shown in Figure 6, the input port 17i of the second solenoid valve 17 communicates with the fluid supply passage LL downstream of the accumulator 14. The first output port 17oa communicates with the unlock fluid chamber 88 of the corresponding joint locking mechanism 8 via a fluid passage formed in the valve body VB, a hose (not shown), the inside of the joint axis Ax, two fluid holes Ah, an annular fluid passage 82p, and a fluid hole 82h (orifice). The second output port 17ob communicates with the second input port 18ib of the shuttle valve 18 via a fluid passage Lb formed in the valve body VB. The first and second drain ports 17da and 17db each communicate with the tank 11 via a fluid return passage LD.

When the spool 17s of the second solenoid valve 17 is de-energized and no current is supplied to the electromagnetic part 17e, the biasing force of the spring 17sp causes the input port 17i to communicate with the second output port 17ob and the first output port 17oa to communicate with the first drain port 17da. Hereinafter, the state in which the spool 17s communicates the input port 17i with the second output port 17ob and the first output port 17oa with the first drain port 17da is referred to as the "lock-enabled state" of the second solenoid valve 17. When the second solenoid valve 17 is in this lock-enabled state, it outputs hydraulic pressure, or line pressure PL, by causing the hydraulic fluid supplied from the fluid supply passage LL to the input port 17i to flow out from the second output port 17ob. When the second solenoid valve 17 is in the locked-allowed state, the hydraulic fluid from the unlock fluid chamber 88 of each joint locking mechanism 8 can be discharged into the tank 11 via the first output port 17oa and the first drain port 17da.

Furthermore, when current is supplied to the electromagnetic part 17e, the spool 17s of the second solenoid valve 17, due to the thrust from the electromagnetic part 17e, overcomes the biasing force of the spring 17sp and connects the input port 17i to the first output port 17oa and the second output port 17ob to the second drain port 17db. Hereinafter, the state in which the spool 17s connects the input port 17i to the first output port 17oa and the second output port 17ob to the second drain port 17db is referred to as the "unlocked state" of the second solenoid valve 17. When the second solenoid valve 17 is in this unlocked state, it supplies the hydraulic fluid (line pressure PL) from the fluid supply passage LL supplied to the input port 17i to the unlocked fluid chamber 88 of each joint locking mechanism 8 from the first output port 17oa. The second solenoid valve 17 may be replaced with an on/off solenoid valve that outputs a signal pressure, and a spool valve (switching valve) that selectively forms a lock-enabled state and a lock-unlocked state in response to the signal pressure supplied from the on/off solenoid valve.

The shuttle valve 18 outputs the higher of the pressure of the hydraulic fluid supplied from the output port 16o of the first solenoid valve 16 to the first input port 18ia via the fluid passage La, and the pressure of the hydraulic fluid supplied from the second output port 17ob of the second solenoid valve 17 to the second input port 18ib via the fluid passage Lb, from its output port 19o. Furthermore, in this embodiment, the fluid passage La connecting the output port 16o of the first solenoid valve 16 and the first input port 18ia of the shuttle valve 18 communicates with the fluid return passage LD via the orifice Ora, as shown in Figure 6.

The on/off valves 191-194 are normally open spool valves with a common configuration, and include a spool 19s that is axially movable within the valve body VB, and a spring 19sp that biases the spool 19s. As shown in Figure 7, the spool 19s of the on/off valves 191-194 has a first land Ld1, a second land Ld2, and a third land Ld3, and the spring 19sp is located within the spring chamber 19z. Furthermore, as shown in Figures 5 to 7, in addition to the spool 19s and spring 19sp, the on/off valves 191-194 include a signal pressure input port 19c, an input port 19i, an output port 19o, and a communication port 19r formed on the opposite side of the spring chamber 19z. The signal pressure input port 19c of the on/off valves 191-194 communicates with the output port 18o of the shuttle valve 18 via corresponding fluid passages formed in the valve body VB.

Such on-off valves 191-194 are provided for each of the first and second fluid chambers 31 and 32 of the multiple double-acting cylinders 3. Specifically, the input port 19i of the on-off valve 191 communicates with the output port 15o of the linear solenoid valve 151 via a fluid passage formed in the valve body VB, and the output port 19o of the on-off valve 191 communicates with the hydraulic fluid inlet and outlet of the first fluid chamber 31 of the double-acting cylinder 3 corresponding to joint Ja via a fluid passage formed in the valve body VB or a hose (not shown). The communication port 19r of the on-off valve 191 communicates with the output port 19o of the on-off valve 191 via a fluid passage formed in the valve body VB, thereby communicating with the hydraulic fluid inlet and outlet of the first fluid chamber 31 of the double-acting cylinder 3 corresponding to joint Ja. Furthermore, the input port 19i of the on/off valve 192 communicates with the output port 15o of the linear solenoid valve 152 via a fluid passage formed in the valve body VB, and the output port 19o of the on/off valve 192 communicates with the hydraulic fluid inlet/outlet of the second fluid chamber 32 of the double-acting cylinder 3 corresponding to joint Ja via a fluid passage formed in the valve body VB or a hose (not shown). The communication port 19r of the on/off valve 192 communicates with the output port 19o of the on/off valve 192 via a fluid passage formed in the valve body VB, thereby communicating with the hydraulic fluid inlet/outlet of the second fluid chamber 32 of the double-acting cylinder 3 corresponding to joint Ja.

Furthermore, the input port 19i of the on/off valve 193 communicates with the output port 15o of the linear solenoid valve 153 via a fluid passage formed in the valve body VB, and the output port 19o of the on/off valve 193 communicates with the hydraulic fluid inlet and outlet of the first fluid chamber 31 of the double-acting cylinder 3 corresponding to joint Jb via a fluid passage formed in the valve body VB or a hose (not shown). The communication port 19r of the on/off valve 193 communicates with the output port 19o of the on/off valve 193 via a fluid passage formed in the valve body VB, thereby communicating with the hydraulic fluid inlet and outlet of the first fluid chamber 31 of the double-acting cylinder 3 corresponding to joint Jb. Furthermore, the input port 19i of the on/off valve 194 communicates with the output port 15o of the linear solenoid valve 154 via a fluid passage formed in the valve body VB, and the output port 19o of the on/off valve 194 communicates with the hydraulic fluid inlet/outlet of the second fluid chamber 32 of the double-acting cylinder 3 corresponding to joint Jb via a fluid passage formed in the valve body VB or a hose (not shown). The communication port 19r of the on/off valve 194 communicates with the output port 19o of the on/off valve 194 via a fluid passage formed in the valve body VB, thereby communicating with the hydraulic fluid inlet/outlet of the second fluid chamber 32 of the double-acting cylinder 3 corresponding to joint Jb.

When no hydraulic pressure is supplied as a signal pressure from the shuttle valve 18 to the signal pressure input port 19c, the spool 19s of the on/off valves 191-194 is biased toward the signal pressure input port 19c side (upper side in Figure 6) by the biasing force of the spring 19sp, opening the input port 19i and connecting the input port 19i to the output port 19o. Hereinafter, the state in which the spool 19s opens the input port 19i and connects the input port 19i to the output port 19o is referred to as the "communication state" of the on/off valves 191-194. When the on/off valves 191-194 are in the communication state, the hydraulic pressure (drive pressure) supplied from the linear solenoid valves 151-154 to the input port 19i can be supplied from the output port 19o to the first or second fluid chambers 31, 32 of each double-acting cylinder 3. Furthermore, when the on/off valves 191-194 are in communication, the hydraulic fluid from the first or second fluid chambers 31 and 32 of each double-acting cylinder 3 can be discharged to the linear solenoid valves 151-154 side via the output port 19o and input port 19i.

In contrast, when hydraulic pressure from the shuttle valve 18 is supplied as a signal pressure to the signal pressure input port 19c, the spool 19s of the on-off valves 191-194 is biased by the thrust based on the signal pressure, as shown in Figure 7, and moves toward the spring chamber 19z side (downward in the figure) against the biasing force of the spring 19sp. As a result, the input port 19i is closed by the first land Ld1, and communication between the input port 19i and the output port 19o is cut off. Hereinafter, the state in which the spool 19s closes the input port 19i and cuts off communication between the input port 19i and the output port 19o is referred to as the "outflow restriction state" of the on-off valves 191-194. When the on/off valves 191-194 are in an outflow restriction state, the outflow of hydraulic fluid from the first or second fluid chambers 31, 32 of each double-acting cylinder 3 to the output port 19o is restricted by the first land Ld1 of the spool 19s.

Furthermore, as shown in Figure 7, the spool 19s of the on/off valves 191-194 has a reduced diameter portion Ldn located between the second and third lands Ld2 and Ld3, and a pressure-receiving surface Lds formed on the second land Ld2 so as to be located on the side of the reduced diameter portion Ldn (lower side in the figure). The reduced diameter portion Ldn faces the communication port 19r when hydraulic pressure from the shuttle valve 18 is supplied as a signal pressure to the signal pressure input port 19c and the on/off valves 191-194 are in an outflow restriction state. The pressure-receiving surface Lds receives the hydraulic fluid flowing into the communication port 19r and generates a thrust in the same direction as the biasing force of the spring 19sp. Furthermore, the reduced-diameter portion Ldn has a small-diameter radial fluid hole Hr that opens on the side of the communication port 19r and extends radially, and an axial fluid hole Ha that communicates with the radial fluid hole Hr and opens at the end face of the third land Ld3 on the spring chamber 19z side. The radial fluid hole Hr and the axial fluid hole Ha form a flow path that connects the communication port 19r and the spring chamber 19z.

As a result, when the on/off valves 191-194 are in an outflow restriction state, the pressure of the hydraulic fluid from the first or second fluid chambers 31, 32 of each double-acting cylinder 3 acts on the pressure-receiving surface Lds through the communication port 19r, the radial fluid hole Hr and axial fluid hole Ha of the reduced diameter portion Ldn. When the sum of the biasing force of the spring 19sp and the thrust due to the hydraulic pressure acting on the pressure-receiving surface Lds becomes greater than the thrust acting on the spool 19s due to the hydraulic pressure supplied to the signal pressure input port 19c, i.e., the signal pressure, the spool 19s moves upward in the figure against the thrust based on the signal pressure, and the on/off valves 191-194 open the input port 19i at least partially and connect the input port 19i to the output port 19o. Furthermore, when the hydraulic fluid pressure from the first or second fluid chambers 31 and 32 of each double-acting cylinder 3 is low, the thrust acting on the spool 19s due to the signal pressure supplied to the signal pressure input port 19c overcomes the sum of the biasing force of the spring 19sp and the hydraulic thrust acting on the pressure-receiving surface Lds, thereby pushing the spool 19s into the spring chamber 19z. At this time, when the third land Ld3 passes through the communication port 19r, the discharge of hydraulic fluid from the spring chamber 19z is suppressed by the small-diameter radially small-diameter hole Hr. This reduces the movement speed of the spool 19s.

The control device 100 of the robot device 1 includes a microcomputer with a CPU, ROM, RAM, input/output interface, and various logic ICs (all not shown). The control device 100 receives detection values from the source pressure sensor PS, and from a voltage sensor (not shown) that detects the voltage of the power supplies for the linear solenoid valves 151-154 and the first and second solenoid valves 16 and 17. The control device 100 also controls the drive unit 130 of the pump 13 so that the hydraulic pressure, i.e., the line pressure PL, in the fluid supply passage LL detected by the source pressure sensor PS becomes the target pressure. Furthermore, the control device 100 controls the current supplied to the electromagnetic parts 15e of the linear solenoid valves 151-154, the electromagnetic part 16e of the first solenoid valve 16, and the electromagnetic part 17e of the second solenoid valve 17.

Furthermore, the control device 100 includes multiple current detection units (not shown) that detect the current flowing through the electromagnetic parts 15e of the linear solenoid valves 151-154 and the electromagnetic parts 16e and 17e of the first and second solenoid valves 16 and 17, and monitors the current detected by each current detection unit. In addition, the control device 100 monitors the detected values from multiple pressure sensors (not shown) that detect the hydraulic pressure in the first and second fluid chambers 31 and 32 of each double-acting cylinder 3, the rotational speed of the pump 13, and the current supplied from the inverter of the drive unit 130 to the electric motor of the pump 13. Based on these currents, pressures, rotational speeds, etc., the control device 100 determines whether or not there is an abnormality in the supply of hydraulic pressure to the first and second fluid chambers 31 and 32 of each double-acting cylinder 3.

Next, referring to Figures 3, 6 through 14, the operation of each joint locking mechanism 8 and the fluid supply device 10 of the robot device 1, configured as described above, will be explained.

While the start switch (not shown) is turned off and the operation of the robot device 1 is completely stopped, the hand portion 7 is held by a locking portion formed on a support base (not shown) or the mounting surface of the robot device 1. Furthermore, the second solenoid valve 17 of the fluid supply device 10 forms the above-mentioned lock-permit state by releasing the power supply to the electromagnetic portion 17e (see Figure 6), and no hydraulic fluid is supplied from the fluid supply device 10 to the lock-release fluid chamber 88 of the joint lock mechanism 8 of each joint Ja, Jb. Accordingly, the slider 83 of each joint lock mechanism 8 is biased to one side in the x-direction (left side in Figure 3) by the coil spring 86 via the spring seat 830, and the two stopper contact portions 83a on the other side in the x-direction of the slider 83 (right side in Figure 3) contact the corresponding stopper portion 82st of the actuator block 82. This ensures that the multiple external teeth 84t of each pole 84 are firmly engaged with the multiple internal teeth 810t of the ring gear 810 (see Figure 3), thereby firmly restricting (locking) the relative rotation of the support member 4 and arm 5a connected via joint Ja, and the relative rotation of arms 5a and 5b connected via joint Jb.

Furthermore, when the start switch of the robot device 1 is turned on and system startup is complete, the control device 100 controls the current supplied to the electromagnetic unit 16e so that the first solenoid valve 16 forms a non-output state in which the input port 16i and output port 16o are blocked from communicating and the output port 16o and drain port 16d are connected. In addition, the control device 100 controls the current supplied to the electromagnetic unit 17e so that the second solenoid valve 17 forms an unlocked state in which the input port 17i and first output port 17oa are connected and the second output port 17ob and second drain port 17db are connected. Furthermore, the control device 100 controls the pump 13 so that the line pressure PL in the fluid supply passage LL is lower than the upper limit pressure Plim and is a relatively high operating pressure set to be above the minimum operating pressure of the accumulator 14. Furthermore, the control device 100 controls the current to the electromagnetic portion 15e of the linear solenoid valves 151-154 so as to supply the hydraulic pressure required to hold the robot arm 2 in the above-mentioned standby position without coercive force from each joint locking mechanism 8 to the first and second fluid chambers 31 and 32 of each double-acting cylinder 3.

As current is supplied to the electromagnetic parts 16e and 17e of the first and second solenoid valves 16 and 17, as shown in Figure 8, hydraulic pressure is not supplied from the output port 16o of the first solenoid valve 16, which forms the output state, to the first input port 18ia of the shuttle valve 18, and hydraulic pressure is not supplied from the second output port 17ob of the second solenoid valve 17, which forms the unlocked state, to the second input port 18ib of the shuttle valve 18. Therefore, signal pressure (hydraulic pressure) is not supplied from the output port 18o of the shuttle valve 18 to the signal pressure input port 19c of each on/off valve 191-194, and each on/off valve 191-194 forms the above-mentioned communication state in which the input port 19i and the output port 19o are connected. This allows the linear solenoid valves 151-154 to supply the hydraulic pressure required to hold the robot arm 2 in the above-mentioned standby position to the first and second fluid chambers 31 and 32 of each double-acting cylinder 3 via the on/off valves 191-194 (see dotted lines in Figure 8).

Furthermore, when current is supplied to the electromagnetic unit 17e, the hydraulic fluid supplied from the fluid supply passage LL to the input port 17i of the second solenoid valve 17, which forms the unlocked state, is supplied to the unlock fluid chamber 88 of the joint lock mechanism 8 of joints Ja and Jb via the first output port 17oa, the inside of the joint axis Ax, the two fluid holes Ah, the annular fluid passage 82p, and the fluid hole 82h. As a result, as shown in Figure 9, the piston 87 of each joint lock mechanism 8 moves to the other side in the x direction (right side in Figure 9), causing the slider 83 to move to the other side in the x direction against the biasing force of the coil spring 86. Consequently, each pole 84 is pulled by the corresponding connecting member 85 and moves inward along the y direction (towards the joint axis Ax), and the engagement between the multiple external teeth 84t of each pole 84 and the multiple internal teeth 810t of the ring gear 810 is released. As a result, relative rotation between the bracket 81 that holds the ring gear 810 and the actuator block 82 that supports each pole 84, that is, relative rotation between the support member 4 and arm 5a and relative rotation between arms 5a and 5b, is permitted.

The control device 100 sets current command values to each electromagnetic unit 15e so that hydraulic pressure corresponding to the robot arm 2 is supplied from the linear solenoid valves 151-154 to the first and second fluid chambers 31 and 32 of each double-acting cylinder 3, and controls the current supplied to each electromagnetic unit 15e based on these current command values. As a result, the hydraulic pressure (drive pressure) adjusted by the linear solenoid valves 151-154 is supplied to the first and second fluid chambers 31 and 32 of each double-acting cylinder 3 via the on/off valves 191-194 (see dotted lines in Figure 8). As a result, the arms 5a, 5b, and 5c can be rotated by the multiple double-acting cylinders 3 to move the hand portion 7 of the robot device 1 to the desired position. Furthermore, the hydraulic fluid flowing out from the first or second fluid chambers 31 and 32 of the double-acting cylinder 3 (in the example in Figure 8, the second fluid chamber 32 of the double-acting cylinder 3 corresponding to joint Jb) due to hydraulic pressure adjustment by the linear solenoid valves 151-154 flows into the fluid return passage LD via the output port 19o and input port 19i of the on/off valves 191-194, and the output port 15o and drain port 15d of the linear solenoid valves 151-154.

On the other hand, if the power supply to the fluid supply device 10 is interrupted or the power supply is lost in response to the operation of an emergency stop button (not shown) while the robot device 1 is in operation, the hydraulic fluid will no longer be discharged from the pump 13, and hydraulic pressure from the accumulator 14 will be supplied to the fluid supply passage LL. Furthermore, if the power supply to each electromagnetic part 15e is cut off due to an interruption of the power supply, etc., the supply of hydraulic fluid (hydraulic pressure) from the linear solenoid valves 151-154 to the first and second fluid chambers 31 and 32 of each double-acting cylinder 3 will cease, and the force restraining the joints Ja and Jb by the multiple double-acting cylinders 3 will be lost.

Furthermore, when the power supply to the electromagnetic part 16e of the first solenoid valve 16 is cut off due to a power outage or the like, the first solenoid valve 16, as shown in Figure 10, forms an output state in which the input port 16i and the output port 16o are connected by the biasing force of the spring 16sp, and outputs hydraulic pressure (line pressure PL) by causing the hydraulic fluid from the fluid supply passage LL (accumulator 14) supplied to the input port 16i to flow out from the output port 16o. Also, when the power supply to the electromagnetic part 17e of the second solenoid valve 17 is cut off due to a power outage or the like, the second solenoid valve 17, as shown in Figure 10, forms a lock-enabled state in which the input port 17i and the second output port 17ob are connected by the biasing force of the spring 17sp, and the first output port 17oa and the first drain port 17da are connected. Furthermore, the second solenoid valve 17 outputs hydraulic pressure (line pressure PL) by causing the hydraulic fluid supplied from the fluid supply passage LL (accumulator 14) to the input port 17i to flow out through the second output port 17ob.

As a result, hydraulic fluid (hydraulic oil) is supplied to the first input port 18ia of the shuttle valve 18 from the output port 16o of the first solenoid valve 16 via the fluid passage La, and hydraulic fluid (hydraulic oil) is supplied to the second input port 18ib of the second solenoid valve 17 from the second output port 17ob of the second solenoid valve 17 via the fluid passage Lb. Here, in the fluid supply device 10, the fluid passage La connecting the output port 16o of the first solenoid valve 16 and the first input port 18ia of the shuttle valve 18 communicates with the fluid return passage LD via the orifice Ora. Therefore, the pressure of the hydraulic fluid supplied from the output port 16o of the first solenoid valve 16 to the first input port 18ia of the shuttle valve 18 is lower than the pressure of the hydraulic fluid supplied from the fluid supply passage LL, i.e., the accumulator 14, to the input ports 16i and 17i of the first and second solenoid valves 16 and 17. Therefore, as shown in Figure 10, the shuttle valve 18 causes the hydraulic fluid from the second solenoid valve 17 to flow out through the output port 18o, at a pressure higher than that of the hydraulic fluid supplied from the first solenoid valve 16 to the first input port 18ia.

As a result, when the power supply from the power source is interrupted or the power source fails, hydraulic pressure from the shuttle valve 18, i.e., hydraulic pressure from the second solenoid valve 17 (line pressure PL), is supplied as a signal pressure to the signal pressure input port 19c of each on-off valve 191-194. Each on-off valve 191-194 then closes its input port 19i and forms an outflow restriction state, blocking communication between the input port 19i and the output port 19o. Therefore, the hydraulic fluid that flows back from the first or second fluid chambers 31, 32 of each double-acting cylinder 3 to the output port 19o of the on-off valve 191-194 is blocked by the spool 19s (first land Ld1), restricting the outflow of the hydraulic fluid to the linear solenoid valve 151-154 side and suppressing sudden changes in the state of each double-acting cylinder 3.

Furthermore, when the second solenoid valve 17 forms a lock-permit state in response to the release of power to the electromagnetic unit 17e, the hydraulic fluid in the unlock fluid chamber 88 of each joint lock mechanism 8 is discharged into the tank 11 via the first output port 17oa, the first drain port 17da, and the fluid return passage LD. As a result, the biasing force of the coil spring 86 of each joint lock mechanism 8 causes the piston 87 and slider 83 to move to one side in the x-direction (the left side in Figure 3). Consequently, each pawl 84 is pressed by the corresponding connecting member 85 and moves outward along the y-direction (towards the ring gear 810), and as shown in Figure 3, the multiple external teeth 84t of each pawl 84 mesh with the multiple internal teeth 810t of the ring gear 810. As a result, the relative rotation between the bracket 81 that holds the ring gear 810 and the actuator block 82 that supports each pole 84, that is, the relative rotation between the support member 4 and the arm 5a and the relative rotation of the arms 5a and 5b, is firmly restricted.

In this case, in the fluid supply device 10, the fluid hole 82h formed in the actuator block 82 functions as an orifice. Therefore, after each on/off valve 191-194 begins to restrict the outflow of hydraulic fluid from the first or second fluid chambers 31 and 32 of each double-acting cylinder 3 in response to the signal pressure supplied from the shuttle valve 18, each joint lock mechanism 8 can restrict the relative rotation between the support member 4 and the arm 5a or the relative rotation of the arms 5a and 5b. This allows for the restriction of the outflow of hydraulic fluid from the first and second fluid chambers 31 and 32 of each double-acting cylinder 3 to suppress sudden changes in the state of each double-acting cylinder 3 when a power supply interruption or power failure occurs, while simultaneously restricting the relative rotation between the support member 4 and the arm 5a and the relative rotation of the arms 5a and 5b by each joint lock mechanism 8 without generating shock, thereby suppressing unexpected movements of the robot arm 2. As a result, the safety of the robot device 1 in the event of a malfunction can be further improved. Furthermore, by suppressing the occurrence of shocks, the need to increase the strength of the support members 4 and arms 5a-5c is reduced, thus suppressing an increase in the overall size and weight of the robot device 1.

In the fluid supply device 10, the fluid passage La connecting the output port 16o of the first solenoid valve 16 and the first input port 18ia of the shuttle valve 18 is connected to the fluid return passage LD via the orifice Ora. Therefore, the hydraulic pressure, i.e., the line pressure PL, supplied from the accumulator 14 to the fluid supply passage LL decreases relatively quickly after the hydraulic fluid is no longer discharged from the pump 13. Consequently, the hydraulic pressure output from the output port 18o of the shuttle valve 18, i.e., the second output port 17ob of the second solenoid valve 17, decreases over time in response to power supply interruptions, and accordingly, the on/off valves 191-194 form a connected state.

Furthermore, once the work using the robot device 1 is completed successfully, the control device 100 controls the current to the electromagnetic parts 15e of the linear solenoid valves 151-154 so that the hand unit 7 is held by a support base or locking part (not shown), and then de-energizes the electromagnetic parts 15e, 16e, and 17e of the linear solenoid valves 151-154 and the first and second solenoid valves 16 and 17. In this case as well, as shown in Figure 10, the hydraulic pressure from the shuttle valve 18, i.e., the line pressure PL from the second solenoid valve 17, is supplied as a signal pressure to the signal pressure input port 19c of each on-off valve 191-194, and each on-off valve 191-194 forms the aforementioned outflow restriction state, restricting the outflow of hydraulic fluid from the first or second fluid chambers 31 and 32 of the corresponding double-acting cylinder 3. Furthermore, after each on/off valve 191-194 begins to restrict the outflow of hydraulic fluid from the first or second fluid chambers 31 and 32 of each double-acting cylinder 3, each joint locking mechanism 8 restricts the relative rotation between the support member 4 and the arm 5a or the relative rotation of the arms 5a and 5b. This makes it possible to restrict the relative rotation between the support member 4 and the arm 5a and the relative rotation of the arms 5a and 5b without generating shock, even when the robot device 1 is normally stopped, by each joint locking mechanism 8.

Incidentally, in the fluid supply device 10, current is constantly supplied to the electromagnetic parts 16e and 17e of the first and second solenoid valves 16 and 17 while the robot arm 2 (robot device 1) is operating. Therefore, the spool 16s of the first solenoid valve 16 may become stuck in a non-output state when energized (ON failure), or the spool 17s of the second solenoid valve 17 may become stuck in an unlocked state when energized (ON failure). Furthermore, with the first or second solenoid valves 16 and 17 in this ON failure state, there is a risk that the emergency stop button may be operated or a power supply failure may occur.

Even if the emergency stop button is operated or a power outage occurs while the spool 16s of the first solenoid valve 16 is stuck in a non-output state, the power supply to each electromagnetic part 15e is released, and hydraulic fluid (hydraulic pressure) is no longer supplied from the linear solenoid valves 151-154 to the first and second fluid chambers 31 and 32 of each double-acting cylinder 3, and the force that restrains the joints Ja and Jb by the multiple double-acting cylinders 3 is lost. Furthermore, as shown in Figure 11, even if the power supply to the electromagnetic part 16e of the first solenoid valve 16 is released, the hydraulic fluid (line pressure PL) from the fluid supply passage LL (accumulator 14) supplied to the input port 16i of the first solenoid valve 16 does not flow out from the output port 16o due to the sticking of the spool 16s. In response to this, as shown in Figure 11, the second solenoid valve 17 forms a locked state in response to the release of power to the electromagnetic unit 17e, and outputs hydraulic pressure (line pressure PL) by causing the hydraulic fluid from the fluid supply passage LL (accumulator 14) supplied to the input port 17i to flow out from the second output port 17ob.

As a result, as shown in Figure 11, the shuttle valve 18 supplies hydraulic pressure from the second solenoid valve 17 as signal pressure to the signal pressure input ports 19c of each on-off valve 191-194. Each on-off valve 191-194 closes its input port 19i and forms an outflow restriction state, blocking communication between the input port 19i and the output port 19o. Therefore, the hydraulic fluid that flows back from the first or second fluid chambers 31, 32 of each double-acting cylinder 3 to the output port 19o of the on-off valve 191-194 is blocked by the spool 19s (first land Ld1), restricting the outflow of the hydraulic fluid to the linear solenoid valve 151-154 side and suppressing sudden changes in the state of each double-acting cylinder 3.

Furthermore, in this case as well, when each on/off valve 191-194 begins to restrict the outflow of hydraulic fluid from the first or second fluid chambers 31, 32 of each double-acting cylinder 3 in response to the supply of signal pressure from the shuttle valve 18, each joint locking mechanism 8 firmly restricts the relative rotation between the support member 4 and the arm 5a and the relative rotation of the arms 5a, 5b in response to the discharge of hydraulic fluid from the unlock fluid chamber 88 via the second solenoid valve 17 which forms a lock-permit state. This allows for the restriction of the outflow of hydraulic fluid from the first and second fluid chambers 31, 32 of each double-acting cylinder 3, thereby suppressing sudden changes in the state of each double-acting cylinder 3, while simultaneously restricting the relative rotation between the support member 4 and the arm 5a and the relative rotation of the arms 5a, 5b without generating shocks, thanks to each joint locking mechanism 8. Therefore, in the robot device 1, even if the emergency stop button is operated or a power outage occurs while the spool 16s of the first solenoid valve 16 is stuck in a non-output state, it is possible to suppress the occurrence of unexpected movements of the robot arm 2.

Furthermore, if the spool 16s of the first solenoid valve 16 is stuck in a non-output state, the hydraulic fluid from the accumulator 14 will not flow into the fluid return passage LD via the orifice Ora. As a result, the hydraulic pressure (line pressure PL) supplied from the accumulator 14 to the fluid supply passage LL will decrease to a state where each on-off valve 191-194 is in communication after a certain amount of time has elapsed since the hydraulic fluid stopped being discharged from the pump 13. Also, if the spool 16s of the first solenoid valve 16 is stuck in a non-output state, after the work using the robot device 1 is completed, it is possible to control the current to the electromagnetic parts 15e of the linear solenoid valves 151-154 to hold the hand part 7 in place on a support base or locking part (not shown). With the hand part 7 held on the support base or the like, the power supply to the electromagnetic parts 15e, 16e, and 17e of the first and second solenoid valves 16 and 17 is released. In this case as well, hydraulic pressure from the second solenoid valve 17 is supplied to the signal pressure input ports 19c of each on-off valve 191-194 via the shuttle valve 18, causing each on-off valve 191-194 to form an outflow restriction state and suppress abrupt changes in the state of each double-acting cylinder 3. Furthermore, when each on-off valve 191-194 begins to restrict the outflow of hydraulic fluid from the first or second fluid chambers 31 and 32 of each double-acting cylinder 3 in response to the supply of signal pressure from the shuttle valve 18, each joint locking mechanism 8 restricts the relative rotation between the support member 4 and the arm 5a and the relative rotation of the arms 5a and 5b without generating shock, in response to the discharge of hydraulic fluid from the unlock fluid chamber 88 via the second solenoid valve 17, which forms a lock-permit state.

On the other hand, if the emergency stop button is operated or a power outage occurs while the spool 17s of the second solenoid valve 17 is stuck in the unlocked state, the power supply to each electromagnetic part 15e is released, and hydraulic fluid (hydraulic pressure) is no longer supplied from the linear solenoid valves 151-154 to the first and second fluid chambers 31 and 32 of each double-acting cylinder 3, and the force that restrains the joints Ja and Jb by the multiple double-acting cylinders 3 is lost. Furthermore, even if the power supply to the electromagnetic part 17e of the second solenoid valve 17 is released, as shown in Figure 12, the hydraulic fluid (line pressure PL) from the fluid supply passage LL (accumulator 14) supplied to the input port 17i of the second solenoid valve 17 does not flow out from the second output port 17ob due to the sticking of the spool 17s. In response, the first solenoid valve 16 forms an output state in response to the release of power to the electromagnetic unit 16e, and outputs hydraulic pressure (line pressure PL) by causing the hydraulic fluid supplied from the fluid supply passage LL (accumulator 14) to the input port 16i to flow out through the output port 16i.

As a result, the shuttle valve 18 supplies hydraulic pressure from the first solenoid valve 16 to the signal pressure input ports 19c of each on-off valve 191-194, as shown in Figure 12. Each on-off valve 191-194 closes its input port 19i and forms an outflow restriction state, blocking communication between the input port 19i and the output port 19o. Therefore, the hydraulic fluid that flows back from the first or second fluid chambers 31, 32 of each double-acting cylinder 3 to the output port 19o of the on-off valve 191-194 is blocked by the spool 19s (first land Ld1), restricting the outflow of the hydraulic fluid to the linear solenoid valve 151-154 side and suppressing sudden changes in the state of each double-acting cylinder 3.

Furthermore, if the spool 17s of the second solenoid valve 17 is stuck in the unlocked state, as shown in Figure 12, the hydraulic fluid (line pressure PL) from the fluid supply passage LL (accumulator 14) supplied to the input port 17i of the second solenoid valve 17 will be continuously supplied to the unlock fluid chamber 88 of each joint locking mechanism 8 via the first output port 17oa. However, since the fluid passage La connecting the output port 16o of the first solenoid valve 16 and the first input port 18ia of the shuttle valve 18 is in communication with the fluid return passage LD via the orifice Ora, the hydraulic pressure (line pressure PL) supplied from the accumulator 14 to the fluid supply passage LL will decrease relatively quickly after the hydraulic fluid is no longer discharged from the pump 13. Therefore, even if the hydraulic fluid from the accumulator 14 is supplied to the unlock fluid chamber 88 of each joint locking mechanism 8 via the first output port 17oa of the second solenoid valve 17, which forms the unlocked state, the hydraulic fluid from the accumulator 14 can be returned to the tank 11 via the first solenoid valve 16 and orifice Ora, thereby reducing the hydraulic pressure (line pressure) output from the first output port 17oa of the second solenoid valve 17 in a relatively short time.

This allows the joint locking mechanism 8 to restrict the relative rotation between the support member 4 and the arm 5a or the arms 5a and 5b, after each on-off valve 191-194 has formed an outflow restriction state, and before it forms a communication state in response to a decrease in the hydraulic pressure (signal pressure) output from the output port 18o of the shuttle valve 18, i.e., the second output port 17ob of the second solenoid valve 17, as shown in Figure 13. As a result, while restricting the outflow of hydraulic fluid from the first and second fluid chambers 31 and 32 of each double-acting cylinder 3 and suppressing sudden changes in the state of each double-acting cylinder 3, the joint locking mechanism 8 can restrict the relative rotation between the support member 4 and the arm 5a and the arms 5a and 5b without generating shock. Therefore, even if the emergency stop button is operated or a power outage occurs while the spool 17s of the second solenoid valve 17 is locked in the unlocked position, it is possible to suppress the occurrence of unexpected movements of the robot arm 2.

Furthermore, even if the spool 17s of the second solenoid valve 17 is stuck in a non-output state, after the work using the robot device 1 is completed, it is possible to control the current to the electromagnetic parts 15e of the linear solenoid valves 151-154 to hold the hand part 7 in place on a support base or locking part (not shown). With the hand part 7 held on the support base or the like, the power supply to the electromagnetic parts 15e, 16e, and 17e of the first and second solenoid valves 16 and 17 is released. In this case as well, hydraulic pressure from the first solenoid valve 16 is supplied to the signal pressure input ports 19c of each on-off valve 191-194 via the shuttle valve 18, causing each on-off valve 191-194 to form an outflow restriction state and suppressing abrupt changes in the state of each double-acting cylinder 3. Furthermore, after each on/off valve 191-194 has formed an outflow restriction state, and before it forms a communication state in response to a decrease in hydraulic pressure (signal pressure) output from the output port 18o of the shuttle valve 18, each joint locking mechanism 8 restricts the relative rotation between the support member 4 and arm 5a and the relative rotation of arms 5a and 5b without generating shock, in response to the discharge of hydraulic fluid from the unlock fluid chamber 88 via the second solenoid valve 17, which forms a lock permission state.

As described above, in the robot device 1, during the operation (movement) of the robot arm 2, the outflow of hydraulic fluid from the first and second fluid chambers 31 and 32 of each double-acting cylinder 3 is restricted by on-off valves 191-194 to suppress sudden changes in the state of each double-acting cylinder 3 in response to power supply interruptions or power failures. However, when the outflow of hydraulic fluid from the first and second fluid chambers 31 and 32 of each double-acting cylinder 3 is restricted by on-off valves 191-194, the inertia of the arm 5a-5c and hand section 7, and the mass of the object being gripped, may cause one of the double-acting cylinders 3 to be pulled or pushed, resulting in a rapid increase in the hydraulic fluid pressure in the first or second fluid chamber 31 and 32.

Based on this, in the robot device 1, in order to suppress the decrease in durability of each double-acting cylinder 3 and hoses (piping) etc. caused by the occurrence of abnormalities, a reduced diameter portion Ldn, a pressure-receiving surface Lds, a radial fluid hole Hr, and an axial fluid hole Ha are formed on the spool 19s of each on-off valve 191-194, which constitute a relief portion. That is, while the on-off valve 191-194 restricts the outflow of hydraulic fluid from the corresponding first or second fluid chambers 31, 32, the reduced diameter portion Ldn of the spool 19s faces the communication port 19r, as shown in Figure 7. In this state, if the pressure of the hydraulic fluid in the first or second fluid chambers 31, 32 rises rapidly due to the relative rotation of the two arms 5a, 5b, etc., the pressure of the hydraulic fluid from the first or second fluid chambers 31, 32 acts on the pressure-receiving surface Lds via the communication port 19r, the radial fluid hole Hr of the reduced diameter portion Ldn, and the axial fluid hole Ha. Then, when the sum of the biasing force of the spring 19sp and the thrust due to the hydraulic pressure acting on the pressure-receiving surface Lds becomes greater than the thrust acting on the spool 19s due to the hydraulic pressure supplied to the signal pressure input port 19c, i.e., the signal pressure, the spool 19s moves upward in Figure 7 against the thrust based on the signal pressure. As a result, the on/off valves 191-194 at least partially open the input port 19i and connect the input port 19i to the output port 19o, and the hydraulic fluid from the first or second fluid chambers 31 and 32 flows out to the fluid return passage LD via the output port 19o and input port 19i of the corresponding on/off valves 191-194, and the output port 15o and drain port 15d of the corresponding de-energized (closed) linear solenoid valves 151-154 (see dashed lines in Figures 10-12).

Thus, the on-off valves 191-194 have a relief function that releases hydraulic fluid from the corresponding first or second fluid chambers 31 and 32 in response to the pressure increase of the hydraulic fluid in the corresponding first or second fluid chambers 31 and 32 while the outflow restriction state is being formed. Therefore, even if any of the double-acting cylinders 3 are pulled or pushed in due to the inertia of the robot arm 2 or other factors while the outflow of hydraulic fluid from the first and second fluid chambers 31 and 32 of each double-acting cylinder 3 is restricted by each on-off valve 191-194, the corresponding on-off valve 191-194 will release the hydraulic fluid from the first or second fluid chamber 31 and 32, thereby suppressing the pressure increase of the hydraulic fluid in that double-acting cylinder 3. As a result, it is possible to suppress the increase in the size and weight of the double-acting cylinders 3 and, consequently, the robot device 1, in order to cope with excessive pressure increases.

Furthermore, when the hydraulic fluid pressure from the first or second fluid chambers 31, 32 of each double-acting cylinder 3 is low, and the relative rotational amount of the two arms 5a, 5b, etc. is zero or relatively small, the thrust acting on the spool 19s due to the signal pressure supplied to the signal pressure input port 19c overcomes the sum of the biasing force of the spring 19sp and the hydraulic thrust acting on the pressure receiving surface Lds, thereby pushing the spool 19s into the spring chamber 19z. At this time, when the third land Ld3 passes through the communication port 19r, the discharge of hydraulic fluid from the spring chamber 19z is suppressed by the small-diameter radially small-diameter hole Hr. This reduces the movement speed of the spool 19s, thereby mitigating the impact when the spool end 19se of the spool 19s contacts the bottom surface 19y of the spring chamber 19z, and making it possible to maintain good durability of the spool 19s and the bottom surface 19y. However, the configuration of the relief section of the on/off valves 191-194 is not limited to those described above.

Now, in the robot device 1, routine maintenance is performed with the start switch (not shown) turned off. However, during maintenance, it may be necessary to release the restrictions on the relative rotation between the support member 4 and the arm 5a, and the relative rotation of the arms 5a and 5b, which are imposed by each joint lock mechanism 8. Furthermore, after the operation of the robot device 1 is stopped due to the operation of the emergency stop button or power failure, inspection and repair will be performed. During inspection and repair, it may also be necessary to release the restrictions on the relative rotation between the support member 4 and the arm 5a, and the relative rotation of the arms 5a and 5b, which are imposed by each joint lock mechanism 8. For this reason, the robot device 1 is provided with a manual lock release mechanism 90 for each joint lock mechanism 8. When the relative rotation between the support member 4 and the arm 5a, and the relative rotation of the arms 5a and 5b are restricted by each joint lock mechanism 8, the manual lock release mechanism 90 can be operated to easily allow the relative rotation between the support member 4 and the arm 5a, and the relative rotation of the arms 5a and 5b.

In other words, as shown in Figure 14, by grasping the knurled bolt 910 as a knob with the hand and rotating the lever 91 counterclockwise around the stepped bolt 901, the third link 93, which is connected to the lever 91 via the second link 92, can be rotated around the stepped bolt 903 such that the pressing member 95 presses against the spring seat 830, moving it to the other side in the first direction (right side in Figure 14). As a result, the slider 83 moves to the other side in the first direction (right side in Figure 14) together with the spring seat 830, and consequently each pole 84 is pulled inward along the y direction (towards the joint axis Ax) by the corresponding connecting member 85, thereby disengaging the multiple external teeth 84t of each pole 84 from the multiple internal teeth 810t of the ring gear 810. As a result, when performing maintenance on the robot device 1, it becomes possible to easily release the restriction on the relative rotation between the support member 4 and the arm 5a, or the relative rotation of the arms 5a and 5b, by the joint locking mechanism 8, without supplying hydraulic fluid from the fluid supply device 10 to the lock release fluid chamber 88 of the joint locking mechanism 8.

Furthermore, the joint locking mechanism 8 includes a spring seat 830 that is fixed to the slider 83 and abuts against the slider 83 side end of the coil spring 86. The manual release mechanism 90 moves the spring seat 830 to the other side in the first direction in response to the operation of the lever 91, and also amplifies the force applied to the lever 91 and transmits it to the spring seat 830. This reduces the force that needs to be applied to the lever 91 to move the slider 83 to the other side in the first direction against the biasing force of the coil spring 86, making it easier to manually release the restriction on the relative rotation between the support member 4 and the arm 5a, or the restriction on the relative rotation of the arms 5a and 5b.

Furthermore, the manual lock release mechanism 90 includes a lever 91 as a first link, a second link 92 rotatably connected to the non-operating end of the lever 91, and a third link 93 connected to the end of the second link 92 opposite to the lever 91, which moves the spring seat 830 to the other side in the first direction. The lever 91 is rotatably supported by a cover 89 fixed to the actuator block 82 via a stepped bolt 901 at a position closer to the non-operating end than the operating end. Furthermore, the third link 93 is rotatably supported by the cover 89 (actuator block 82) via a stepped bolt 903 between the end on the second link 92 side and the end on the spring seat 830 side. In a manual unlocking mechanism 90 composed of a four-bar linkage mechanism including a lever 91 as the first link, second and third links 92 and 93, and an actuator block 82 and cover 89 as fixed links, as shown in Figure 14, by moving the lever 91 to a position beyond the dead center of the four-bar linkage mechanism where the axis of the stepped bolt 901, the axis of the connecting pin 902, and the axis of the connecting pin 904 are aligned in a straight line, it becomes possible to restrict the rotation of the lever 91 and the second and third links 92 and 93 without applying force to the lever 91, thereby continuing to allow relative rotation between the support member 4 and the arm 5a or between the arms 5a and 5b.

Furthermore, the lever 91 can be fixed to the cover 89 (actuator block 82) at a position beyond the dead center of the four-bar linkage mechanism, which includes the lever 91, the second and third links 92 and 93, and the actuator block 82 as a fixed link. Specifically, a bolt hole 91h into which a knurled bolt 910 can be screwed is formed at the operating end of the lever 91 (see Figure 3), and a bolt hole 89h is formed in the cover 89 at a position beyond the dead center of the four-bar linkage mechanism, which includes the lever 91, that overlaps with the bolt hole 91h of the lever 91 (see Figure 4). As a result, after moving the lever 91 to the position shown in Figure 14, the knurled bolt 910 can be removed from the lever 91 and screwed into the bolt hole 91h and the bolt hole 89h of the cover 89, thereby fixing the lever 91 to the cover 89, i.e., the actuator block 82. As a result, even if an external force is applied to the manual lock release mechanism 90 during maintenance, inspection, or repair, the rotation of the lever 91 and the second and third links 92 and 93 can be more reliably restricted.

Furthermore, in the above embodiment, the range from the portion of the lever 91 supported by the stepped bolt 901 to the end on the knurled bolt 910 side, and the range from the portion of the third link 93 supported by the stepped bolt 903 to the end on the pressing member 95 side, are curved or bent to approach the joint axis Ax. This prevents the manual lock release mechanism 90 from protruding outward from the outer circumference of the bracket 81, making the entire joint lock mechanism 8 more compact.

As described above, in the joint locking mechanism 8 of the robot device 1, when hydraulic fluid (fluid) is not supplied from the fluid supply device 10 to the unlocking fluid chamber 88 of the unlocking actuator FA, which includes the cylinder bore 82c and piston 87, the slider 83 is biased to one side in the x-direction (first direction) by the coil spring 86, and the multiple external teeth 84t of the pole 84 engage with some of the multiple internal teeth 810t on the bracket (first member) 81 side. As a result, the bracket 81, slider 83, pole 84, and actuator block (second member) 82 are integrated, and the relative rotation between the support member 4 and the arm 5a or the relative rotation of the arms 5a and 5b is restricted. Conversely, when hydraulic fluid is supplied from the fluid supply device 10 to the unlocking fluid chamber 88 of the unlocking actuator FA, the unlocking actuator FA moves the slider 83 to the other side in the x-direction against the biasing force of the coil spring 86. This disengages the multiple external teeth 84t of the pole 84 from some of the multiple internal teeth 810t on the bracket 81, allowing relative rotation between the bracket 81 and the actuator block 82, i.e., relative rotation between the support member 4 and the arm 5a, or relative rotation between the arms 5a and 5b.

Thus, in the joint locking mechanism 8 of this disclosure, the relative rotation between the support member 4 and the arm 5a, or the relative rotation between the arms 5a and 5b, can be smoothly and effectively restricted or permitted by moving the slider 83 to one or the other side in the x-direction using the coil spring 86 or the unlocking actuator FA. Furthermore, the stroke required for the unlocking actuator FA, i.e., the piston 87, is significantly smaller than that required for a joint locking mechanism that uses a rotating cam to engage a portion of the multiple external teeth 84t of the pole 84 supported by the actuator block 82 with a portion of the multiple internal teeth 810t on the bracket 81 side. Therefore, it is possible to miniaturize the unlocking actuator FA and make the entire joint locking mechanism 8 more compact.

Furthermore, when the slider 83 is biased to one side in the x-direction by the coil spring 86, thereby restricting the relative rotation of the support member 4 and the arm 5a, or the relative rotation of the arms 5a and 5b, manually operating the lever 91 of the manual lock release mechanism 90 will move the slider 83 to the other side in the x-direction against the biasing force of the coil spring 86, thereby allowing the relative rotation of the support member 4 and the arm 5a, or the relative rotation of the arms 5a and 5b. This makes it possible to easily release the restriction on the relative rotation of the support member 4 and the arm 5a, or the restriction on the relative rotation of the arms 5a and 5b by the joint lock mechanism 8 during maintenance, etc., without supplying hydraulic fluid from the fluid supply device 10 to the joint lock mechanism 8. Therefore, the joint locking mechanism 8 allows for a compact overall device while smoothly and effectively restricting or allowing the relative rotation of the support member 4 and arm 5a connected via joint Ja, or the relative rotation of arms 5a and 5b connected via joint Jb, and easily releasing the restriction on the relative rotation of the support member 4 and arm 5a or arms 5a and 5b.

Furthermore, in the joint locking mechanism 8, the coil spring 86, acting as a biasing member, is positioned on one side of the joint axis Ax in the x-direction. The unlock actuator FA includes a cylinder bore (cylinder) 82c formed in the actuator block 82 so as to be located on the other side of the joint axis Ax in the x-direction, a piston 87 slidably positioned within the cylinder bore 82c so as to abut the slider 83, and an unlock fluid chamber 88 defined on one side of the piston 87 in the x-direction by the inner circumferential surface of the cylinder bore 82c and the piston 87. This allows both the coil spring 86 and the unlock actuator FA to be positioned in the actuator block 82, making the entire joint locking mechanism 8 more compact.

Furthermore, in the robot device 1, the fluid supply device 10 can be shared between the support member 4, the multiple double-acting cylinders 3 that rotate the arm 5a or arms 5a and 5b relative to each other, and the joint locking mechanism 8. This allows for a significantly more compact overall device.

Furthermore, in the fluid supply device 10, at least one of the linear solenoid valves 151-154 may be a normally open valve. In this case, the normally open valve may balance the thrust from the electromagnetic part and the thrust from the hydraulic pressure supplied to the feedback port so as to act in the same direction as the thrust from the electromagnetic part with the biasing force of the spring. Also, at least one of the linear solenoid valves 151-154 may not have a dedicated feedback port and may be configured to apply the output pressure (drive pressure) as feedback pressure to the spool inside the sleeve housing the spool (see, for example, Japanese Patent Application Publication No. 2020-41687). Moreover, at least one of the linear solenoid valves 151-154 may be replaced with a linear solenoid valve that outputs a signal pressure corresponding to the current supplied to the electromagnetic part and a control valve that adjusts the pressure of the hydraulic fluid according to the signal pressure. Furthermore, the fluid supply device 10 may include, instead of the linear solenoid valves (fluid control valves) 151-154, a flow control valve that controls the flow rate of hydraulic fluid to the double-acting cylinder 3 so that the hydraulic pressure (fluid pressure) detected by, for example, a pressure sensor reaches the required pressure.

Furthermore, the robot device 1 (robot arm 2) may include only one joint, or only one or two double-acting cylinders 3. Also, the robot device 1 is not limited to a robot arm 2 having at least one double-acting cylinder 3 and a hand portion 7; it may include at least one fluid actuator and a robot arm with elements other than the hand portion 7 attached to its end effector, such as a tool like a drill bit or a pressing member for pressing switches. Furthermore, the robot device 1 may be a walking robot, a wearable robot, or the like.

Furthermore, the robot arm 2 of the robot device 1 may include a rocking motor (for example, a rocking motor that rotates the base (wrist) of the hand portion 7) as a fluid actuator (double-acting actuator) that drives the arms 5a-5c. That is, the robot arm 2 of the robot device 1 may include at least one of a double-acting cylinder 3 and a rocking motor. Moreover, in the robot device 1, at least one of the double-acting cylinders 3 may be replaced with a double-acting actuator including, for example, two single-acting cylinders arranged to be antagonistic to each other, a double-acting actuator including two McKibben-type artificial muscles arranged to be antagonistic to each other, or a double-acting actuator including two axial fiber-reinforced fluid actuators arranged to be antagonistic to each other (for example, see Japanese Patent Application Publication No. 2011-137516). Also, the robot arm 2 of the robot device 1 may include an air cylinder as a fluid actuator. Furthermore, one or more single-acting cylinders and elastic bodies such as springs or rubber materials, positioned to oppose the one or more single-acting cylinders, may be connected to any two arms 5a and 5b connected via joints Ja and Jb.

As described above, the joint locking mechanism of the present disclosure is a joint locking mechanism (8) that receives fluid from a fluid supply device (10) and restricts or allows the relative rotation of two links (4, 5a, 5b) connected via a joint (Ja, Jb) depending on the fluid supply state by the fluid supply device (10), the mechanism comprising a first member (81) fixed to one of the two links (4, 5a, 5b), and a first member (81) rotatable relative to the first member (81) around the joint axis (Ax) of the joint (Ja, Jb). A second member (82) fixed to the other of the two links (4, 5a, 5b), a plurality of internal teeth (810t) provided on the first member (81), a slider (83) supported by the second member (82) so as to be movable in a first direction (x), and a plurality of external teeth (84t) that can mesh with the plurality of internal teeth (810t) of the first member (81), and the second member (82) moves toward and away from the plurality of internal teeth (810t) along a second direction (y) intersecting the first direction (x) A supported pole (84), a connecting member (85) rotatably connected to the slider (83) and rotatably connected to the pole (84), which moves the pole (84) in the second direction (y) in response to the movement of the slider (83) in the first direction (x), and a second member (82) positioned between the slider (83) and the second member (82), which moves the slider (83) in the first direction (x) such that the plurality of external teeth (84t) of the pole (84) mesh with the plurality of internal teeth (810t) The system includes a biasing member (86) that biases to one side, a release actuator (FA) that moves the slider (83) to the other side in the first direction (x) against the biasing force of the biasing member (86) in response to the supply of the fluid from the fluid supply device (10), and a manual release mechanism (90) having a manually operated lever (91) that moves the slider (83) to the other side in the first direction (x) against the biasing force of the biasing member (86) in response to the operation of the lever (91).

In the joint locking mechanism of this disclosure, when fluid is not supplied from the fluid supply device to the unlock actuator, the slider is biased to one side in the first direction by the biasing member, and the multiple external teeth of the pole engage with the multiple internal teeth provided on the first member. As a result, the first member, slider, pole, and second member are integrated, and the relative rotation of the two links is restricted. Conversely, when fluid is supplied from the fluid supply device to the unlock actuator, the unlock actuator moves the slider to the other side in the first direction against the biasing force of the biasing member. As a result, the engagement between the multiple external teeth and the multiple internal teeth of the pole is released, and the relative rotation of the first member and the second member, i.e., the two links, is permitted. Thus, in the joint locking mechanism of this disclosure, the relative rotation of the two links can be smoothly and effectively restricted or permitted by moving the slider to one side or the other side in the first direction by the biasing member or the unlock actuator. Furthermore, the stroke required for the unlock actuator is significantly smaller compared to a joint lock mechanism that uses a rotating cam to engage multiple external teeth of a pole supported by a second member with multiple internal teeth on the first member side. Therefore, it is possible to miniaturize the unlock actuator and thus the entire joint lock mechanism. Moreover, when the slider is biased to one side in the first direction by a biasing member, restricting the relative rotation of the two links, manually operating the lever of the manual unlock mechanism allows the slider to move to the other side in the first direction against the biasing force of the biasing member, thereby allowing the relative rotation of the two links. This makes it possible to easily release the restriction on the relative rotation of the two links by the joint lock mechanism during maintenance, etc., without supplying fluid from a fluid supply device to the joint lock mechanism. Therefore, the joint lock mechanism of this disclosure allows for a compact overall device while smoothly and effectively restricting or allowing the relative rotation of two links connected via a joint, and easily releasing the restriction on the relative rotation of the two links.

Furthermore, the joint locking mechanism (8) may include a contact member (830) that is fixed to the slider (83) and abuts against the slider (83) side end of the biasing member (86). The manual lock release mechanism (90) may be a toggle mechanism that moves the contact member (830) to the other side in the first direction (x) in response to the operation of the lever (91), and amplifies the operating force from the operation of the lever (91) and transmits it to the contact member (830).

This reduces the force required to move the slider to the other side in the first direction against the biasing force of the biasing member, making it easier to manually release the restriction on the relative rotation of the two links.

Furthermore, the manual lock release mechanism (90) may include a lever (91) as a first link, a second link (92) rotatably connected to the non-operating end of the lever (91), and a third link (93) connected to the end of the second link (92) opposite to the lever (91), which moves the contact member (830) to the other side in the first direction (x). The lever (91) may be rotatably supported by the second member (92) at a position closer to the non-operating end than the operating end, and the third link (93) may be rotatably supported by the second members (82, 89) between the end on the second link (92) side and the end on the contact member (830) side.

In a manual unlocking mechanism (toggle mechanism) consisting of a four-bar linkage mechanism including a lever as the first link, second and third links, and a second member as a fixed link, moving the lever beyond the dead center of the four-bar linkage mechanism allows for restricting the rotation of the first to third links while still allowing relative rotation of the two links, without applying force to the lever.

Furthermore, the lever (91) may be fixable to the second member (82, 89) at a position beyond the dead center of the four-bar linkage mechanism, which includes the lever (91) as the first link, the second and third links (92, 93), and the second member (82, 89) as a fixed link.

This makes it possible to more reliably restrict the rotation of the first to third links, even if an external force is applied to the manual unlocking mechanism during maintenance or other procedures.

Furthermore, the biasing member (86) may be positioned on one side of the joint axis (Ax) in the first direction (x), and the unlock actuator (FA) may include a cylinder (82, 82c) formed on the second member (82) so as to be located on the other side of the joint axis (Ax) in the first direction (x), a piston (87) slidably disposed within the cylinder (82, 82c) so as to abut the slider (83), and an unlock fluid chamber (88) defined on one side of the piston (87) in the first direction (x) by the inner circumferential surface of the cylinder (82, 82c) and the piston (87).

This allows both the biasing member and the unlocking actuator to be placed in the second member, making the entire joint locking mechanism more compact.

The robotic apparatus of this disclosure is a robotic apparatus (1) including any of the above-described joint locking mechanisms (8), and includes at least one fluid actuator (3) that operates by receiving the fluid from the fluid supply device (10) and rotates the two links (4, 5a, 5b) relative to each other.

In such a robotic device, the fluid supply device can be shared between at least one fluid actuator that rotates the two links relative to each other and the joint locking mechanism, making it possible to significantly compact the entire device.

Furthermore, the invention disclosed herein is not limited in any way to the embodiments described above, and it goes without saying that various modifications can be made within the scope of this disclosure. Moreover, the embodiments described above are merely specific forms of the invention described in the "Summary of Invention" section, and do not limit the elements of the invention described in the "Summary of Invention" section.

The invention disclosed herein is applicable to the manufacturing industry and other fields of robotic devices, including those comprising two links connected via joints.

1. Robot device, 2. Robot arm, 3. Double-acting cylinder, 30. Cylinder, 31. First fluid chamber, 32. Second fluid chamber, 34. Piston, 35. Piston rod, 4. Support member (link), 5a, 5b, 5c. Arm (link), 8. Joint locking mechanism, 81. Bracket (first member), 810. Ring gear, 810t. Internal teeth, 82. Actuator block (second member), 82c. Cylinder bore, 82h. Fluid bore, 82p. Fluid passage, 83. Slider, 830. Spring seat, 84. Pole, 84t. External teeth, 85. Connecting member, 86. Coil spring, 87. Piston, 88. Unlock fluid chamber, 89. Cover, 90. Manual unlock mechanism, 91. Lever, 92. Second link, 93. Third link, 10. Fluid supply device, Ax. Joint axis, FA. Unlock actuator, Ja, Jb, Jc. Joints.

Claims (6)

A joint locking mechanism that receives fluid from a fluid supply device and restricts or allows the relative rotation of two links connected via a joint, depending on the fluid supply state by the fluid supply device,
A first member fixed to one of the two links,
A second member is fixed to the other of the two links so as to be rotatable relative to the first member around the joint axis of the joint,
Multiple internal teeth provided on the first member,
A slider is supported by the second member so as to be movable in the first direction,
A pole having a plurality of external teeth that can mesh with the plurality of internal teeth of the first member, and supported by the second member so as to move toward and toward the plurality of internal teeth along a second direction intersecting the first direction,
A connecting member is rotatably connected to the slider and also rotatably connected to the pole, and moves the pole in the second direction in accordance with the movement of the slider in the first direction,
A biasing member is positioned between the second member and the slider and biases the slider to one side in the first direction such that the plurality of external teeth of the pole mesh with the plurality of internal teeth,
A release actuator comprising a cylinder formed in the second member and a piston slidably disposed within the cylinder, wherein the piston moves in response to the supply of the fluid from the fluid supply device, thereby moving the slider to the other side in the first direction against the biasing force of the biasing member,
A manual unlocking mechanism having a manually operated lever, which moves the slider to the other side in the first direction against the biasing force of the biasing member in response to the operation of the lever,
A joint locking mechanism equipped with this mechanism. In the joint locking mechanism described in claim 1,
The slider is further equipped with a contact member that is fixed to the slider and abuts against the slider-side end of the biasing member,
The manual lock release mechanism is a joint lock mechanism which is a toggle mechanism that moves the contact member to the other side in the first direction in response to the operation of the lever, and amplifies the operating force by the operation of the lever and transmits it to the contact member. In the joint locking mechanism described in claim 2,
The manual lock release mechanism includes the lever as a first link, a second link rotatably connected to the non-operating end of the lever, and a third link connected to the end of the second link opposite to the lever side, which moves the contact member to the other side in the first direction.
The lever is rotatably supported by the second member at a position closer to the non-operating end than to the operating end, and the third link is rotatably supported by the second member between the end on the second link side and the end on the contact member side in this joint locking mechanism. In the joint locking mechanism described in claim 3,
The lever is a joint locking mechanism that can be fixed to the second member at a position beyond the dead center of a four-bar linkage mechanism including the lever as the first link, the second and third links, and the second member as a fixed joint. In the joint locking mechanism according to any one of claims 1 to 4,
The biasing member is positioned on one side in the first direction of the joint axis,
The aforementioned unlock actuator is
A cylinder formed on the second member so as to be located on the other side in the first direction of the joint axis,
A piston is slidably positioned within the cylinder so as to contact the slider,
An articulated locking mechanism including an unlocking fluid chamber defined on one side of the piston in a first direction by the inner circumferential surface of the cylinder and the piston. A robotic device comprising a joint locking mechanism according to any one of claims 1 to 5,
A robotic device comprising at least one fluid actuator that operates by receiving the fluid from the fluid supply device and rotates the two links relative to each other.