JP7625467B2 - robot - Google Patents

Description

The present invention relates to a robot.

As disclosed in the following Patent Document 1, a robot is known that includes a first member (e.g., an upper arm), a second member (e.g., a forearm), and a joint that connects the first and second members. The joint is provided with a motor and a reducer, and the driving force generated by the motor causes the second member to rotate relative to the first member via the reducer.

Special Publication No. 2020-508035

In the robot disclosed in Patent Document 1, a motor that generates a driving force that causes rotation between the first and second members is provided in the joint, so when driving the motor while a load is applied to the tip of the second member, which is the forearm, a large torque needs to be generated. In other words, a large torque needs to be generated in order to generate torque near the center of rotation of the first and second members. Therefore, in the robot disclosed in Patent Document 1, it is necessary to use a motor that generates a large torque, assuming the load applied to the tip of the forearm.

Therefore, the present invention was made in consideration of the above-mentioned conventional technology, and its purpose is to generate relative rotation between the first member and the second member with a smaller torque.

In order to achieve the above object, the present invention provides a first linear motor having a first member, a second member, a joint portion that rotatably connects the first member and the second member to each other, a first long element extending along a direction in which the first member extends and disposed on the first member, and a first short element movable along the first long element, and a first link member having one end rotatably connected directly or indirectly to the second member and another end rotatably connected to the first short element, wherein a fixed member extending in one direction is fixed to the second member, the one end of the first link member is rotatably connected to the fixed member, and the fixed member is constituted by the second long element of a second linear motor having a second long element and a second short element, or is constituted by a second long element member fixed to the second long element, and the second long element a second link member is provided which is formed in a shape extending in the extension direction of the second member and has one end which is rotatably connected to the second short member and the other end which is rotatably connected to the first long member or a first long member member fixed to the first long member; by supplying power to the first linear motor, the first short member is moved relative to the first long member, thereby generating a moment around the joint in the second member via the first link member, causing a relative rotational movement between the first member and the second member; and by supplying power to the second linear motor, the second short member is moved along the second long member, thereby generating a moment around the joint in the first member via the second link member, thereby causing a relative rotational movement between the first member and the second member.

In the present invention, by supplying power to a linear motor having a long element arranged on the first member, a moment is generated around the joint in the second member via the link member, causing relative rotational movement between the first member and the second member. Therefore, compared to a configuration in which a rotational torque is generated near the joint, it is possible to cause relative rotational movement between the first member and the second member with a smaller torque. Moreover, because the linear motor is arranged on the first member and is not housed within the joint, it is possible to avoid an increase in the size of the joint.

Furthermore , since the link member is rotatably connected to the fixed member that is shaped to extend in one direction, the second member is suitable for a robot configured as an arm, for example.

Furthermore , since the relative rotational movement between the first member and the second member is caused by using a linear motor and a second linear motor, the torque of each linear motor can be further reduced, allowing the linear motors to be made smaller.

The present invention provides a first linear motor having a first member, a second member, a joint portion that rotatably connects the first member and the second member to each other, a first long element that has a shape extending in one direction and is arranged on the first member, and a first short element that can move along the first long element, and a first link member having one end that is rotatably connected directly or indirectly to the second member and the other end that is rotatably connected to the first short element, wherein a fixed member that extends in one direction is fixed to the second member, the one end of the first link member is rotatably connected to the fixed member, and the fixed member is constituted by the second long element of a second linear motor having a second long element and a second short element, or is constituted by a second long element member fixed to the second long element, and the first link member is rotatably connected to the second short element. A second link member is provided having one end which can be rotatably connected to the first long element or the other end which can be rotatably connected to the first long element or a first long element member fixed to the first long element, and by supplying power to the first linear motor, the first short element is moved along the first long element, thereby generating a moment about the joint in the second member via the first link member, and by supplying power to the second linear motor, the second short element is moved along the second long element, thereby generating a moment about the joint in the first member via the second link member, thereby generating a relative rotational movement between the first member and the second member, and the timing at which the first short element passes through the dead center is set to be shifted from the timing at which the second short element passes through the dead center.

In the present invention, by supplying power to a linear motor having a long element arranged on the first member, a moment is generated around the joint in the second member via the link member, causing relative rotation between the first member and the second member. Therefore, compared to a configuration in which a rotational torque is generated near the joint, it is possible to cause relative rotation between the first member and the second member with a smaller torque. Moreover, since the linear motor is arranged on the first member and is not housed in the joint, it is possible to avoid an increase in the size of the joint.
In addition, the timing at which the short element passes the dead point is set to be shifted from the timing at which the second short element passes the dead point. Therefore , the second short element is not at the dead point when the short element passes the dead point. Furthermore, the second short element is not at the dead point when the second short element passes the dead point. Therefore, even if the short element is at the dead point, the rotational movement between the first member and the second member via the link member can be continued, and even if the second short element is at the dead point, the rotational movement between the first member and the second member via the second link member can be continued. Therefore, the rotational movement between the first member and the second member can be made into a continuous series of movements.

The present invention is a robot comprising: a first member, a second member, a joint portion connecting the first member and the second member to each other so that they can rotate; a first linear motor having a first long element having a portion extending along the first member and arranged on the first member; a first short element movable relative to the first long element along the portion of the first long element; a second linear motor having a second long element having a portion extending along the second member and a second short element movable relative to the second long element along the portion of the second long element; and a link member having one end portion rotatably connected to the first short element and the other end portion rotatably connected to the second short element; and when power is supplied to the first linear motor and the second linear motor, the first short element moves relative to the first long element and the second short element moves relative to the second long element, thereby causing a relative rotational movement between the first member and the second member.

In the present invention, when the first and second short shafts are slid by supplying power to the first and second linear motors, a force that changes the opening angle between the first and second members is applied by the link member, thereby causing a relative rotational movement between the first and second members. Therefore, compared to a configuration in which a rotational torque is generated near the joint, it is possible to cause a relative rotational movement between the first and second members with a smaller torque. Moreover, since the linear motor is disposed on the first member and the second linear motor is disposed on the second member, and the two linear motors are not housed within the joint, the joint can be prevented from becoming large.

The present invention relates to a linear motor comprising: a first member, a second member, a joint portion rotatably connecting the first member and the second member to each other, a first long element having a portion extending in one direction and disposed on the first member, and a first short element movable along the portion of the first long element relative to the first long element, a second linear motor having a second long element having a portion extending along the second member, and a second short element movable along the portion of the second long element relative to the second long element, and a link member having one end rotatably connected to the first short element and the other end rotatably connected to the second short element, The linear motor further includes a first short element brake capable of switching between a state in which the first short element is fixed to the first member and a state in which the second short element is not fixed to the second member by supplying power to the first linear motor and the second linear motor, thereby causing a relative rotational movement between the first member and the second member, and a second short element brake capable of switching between a state in which the second short element is fixed to the second member and a state in which it is not fixed to the second member , wherein the first long element is supported so as to be displaceable in the extension direction of the first long element, and the second long element is supported so as to be displaceable in the extension direction of the second long element.

In the present invention, when the first and second short members are slid by supplying power to the first and second linear motors, a force that changes the opening angle between the first and second members is applied by the link member, thereby causing a relative rotational movement between the first and second members. Therefore, the relative rotational movement between the first and second members can be caused with a smaller torque than in a configuration in which a rotational torque is generated near the joint. Moreover, since the linear motor is disposed on the first member and the second linear motor is disposed on the second member, and the two linear motors are not housed in the joint, the joint can be prevented from becoming large.
In addition , when the first long element slides in the longitudinal direction, the range of movement of the first short element can be increased accordingly, and when the second long element slides in the longitudinal direction, the range of movement of the second short element can be increased accordingly, thereby increasing the relative rotation range between the first member and the second member.

The first and second elongated elements may have a plurality of teeth arranged in the longitudinal direction. In this case, a pinion may be provided that meshes with the plurality of teeth of the first and second elongated elements.

In this embodiment, the relationship between the amount of sliding of the first elongated element relative to the first member and the amount of sliding of the second elongated element relative to the second member can be determined by the pinion.

As described above, according to the present invention, it is possible to generate relative rotation between the first and second members with a smaller torque.

FIG. 1 is a diagram illustrating a robot according to a first embodiment. 3A to 3C are diagrams for explaining the configuration of a linear motor provided in the robot. 13A and 13B are diagrams for explaining the configuration of a modified example of a linear motor provided in the robot. 5A to 5C are diagrams for explaining the movement of the robot. FIG. 13 is a diagram showing a robot according to a modified example of the first embodiment. 13A to 13C are diagrams illustrating the movement of a robot according to a second embodiment. 13A to 13B are diagrams illustrating the movement of a robot according to a third embodiment. 13A to 13B are diagrams illustrating the movement of a robot according to a fourth embodiment. 13A to 13C are diagrams illustrating the movement of the robot according to the fourth embodiment. 13A to 13C are diagrams illustrating the movement of a robot according to a fifth embodiment.

The following describes in detail the embodiment of the present invention with reference to the drawings.

First Embodiment
As shown in FIG. 1, the robot 10 according to the first embodiment includes a first member 11, a second member 12, and a joint 13 that connects the first member 11 and the second member 12 to each other so as to be rotatable. Both the first member 11 and the second member 12 are formed of arm-shaped members, but the present invention is not limited to this. The robot 10 may be configured, for example, as a part of a humanoid robot, or as a part of a multi-joint six-axis robot. When the robot 10 is a part of a humanoid robot, for example, the first member 11 may constitute an upper arm and the second member 12 may constitute a forearm. Alternatively, the first member 11 may constitute a forearm and the second member 12 may constitute an upper arm. Alternatively, the first member 11 may constitute a trunk and the second member 12 may constitute an upper arm. Alternatively, the first member 11 may constitute a trunk and the second member 12 may constitute a trunk. FIG. 1 illustrates a case in which a first member 11 constitutes an upper arm, and a second member 12 constitutes a forearm, with an end effector 14 being provided at the tip of the second member 12.

The joint portion 13 has a first portion (not shown) that is connected to the first member 11 and a second portion (second portion) that is connected to the second member 12, and the first portion and the second portion are connected to each other so as to be rotatable.

A linear motor 21 is disposed on the first member 11. The linear motor 21 has a long element 21a fixed to the first member 11, and a short element 21b that moves relative to the long element 21a due to the action of electromagnetic force caused by power supply to the linear motor 21. The long element 21a has a shape that extends linearly in one direction, and this extending direction passes through a position offset from the rotation axis 13a of the joint 13. However, this is not limited to this, and the long element 21a may be disposed to extend in the radial direction of the rotation axis 13a so as to pass through the rotation axis 13a of the joint 13.

As shown in FIG. 2, the long element 21a may be composed of multiple armatures 23, and the short element 21b may be composed of multiple magnetic pole pieces 24. Alternatively, as shown in FIG. 3, the long element 21a may be composed of multiple magnetic pole pieces 24, and the short element 21b may be composed of multiple armatures 23.

In the configuration shown in FIG. 2, a large number of armatures 23 having coils (not shown) are arranged in one direction, so that the long element 21a is formed into a shape that extends along the extension direction of the first member 11. The short element 21b is configured to have a plurality of magnetic pole pieces 24 arranged so that the north poles and south poles are staggered. When power is supplied to the armature 23, magnetic lines of force are generated that pass through the magnetic pole pieces 24 and the short element 21b, causing the short element 21b to slide along the long element 21a. The linear motor 21 configured as shown in FIG. 2 is configured, for example, by a brushless motor or an induction motor.

On the other hand, in the configuration shown in Fig. 3, the long element 21a has many magnetic pole pieces 24 arranged in one direction with N poles and S poles alternated. The short element 21b has a plurality of armatures 23 each having a coil. When power is supplied to the armatures 23, magnetic field lines M passing through the magnetic pole pieces 24 and the short element 21b are generated, causing the short element 21b to slide along the long element 21a. The linear motor 21 shown in Fig. 3 is, for example, a DC motor that receives power through brushes (not shown).

Returning to FIG. 1, as shown in FIG. 1, a fixed member 27 is fixed to the second member 12, and the robot 10 is provided with a link member 29 that connects the fixed member 27 to the short member 21b.

The fixing member 27 is composed of a member having an integral long portion 27a extending from the rotation axis 13a of the joint portion 13 along the radial direction of the rotation axis 13a, and a protruding portion 27b protruding from the outer end of the long portion 27a in the rotation direction. Note that the shape of the long portion 27a is not limited to a shape extending linearly in the radial direction of the rotation axis 13a, but may be formed in a curved shape that deviates from the radial direction. In this case, the protruding portion 27b may be omitted. Furthermore, even when the long portion 27a is formed linearly, the protruding portion 27b may be omitted.

The link member 29 is composed of a rod-shaped member extending linearly, and one end of the link member 29 (the second end 29b, which is the end on the second member 12 side) is rotatably connected to the protruding portion 27b of the fixed member 27. In other words, the link member 29 is indirectly connected to the second member 12. The other end of the link member 29 (the first end 29a, which is the end on the first member 11 side) is rotatably connected to the short member 21b. Note that when the protruding portion 27b is omitted, one end of the link member 29 is rotatably connected to the long portion 27a of the fixed member 27.

Now, the movement of the robot 10 will be described with reference to Figures 4(a) to (c). In Figure 4(a), the first member 11 is at the 12 o'clock position, and the extension line of the long element 21a is shifted to the left of the figure relative to the rotation axis 13a, and the second member 12 is in a position where the outer end is located to the left of the extension line of the long element 21a (7 o'clock position). At this time, the short element 21b is located near the inner end of the long element 21a. In this state, when power is supplied to the linear motor 21 so as to move the short element 21b radially inward along the long element 21a, a moment is generated around the joint 13 in the second member 12 via the link member 29 in a direction in which the angle between the first member 11 and the second member 12 approaches 180 degrees. As a result, the second member 12 rotates in the counterclockwise direction from the state shown in Figure 4(a).

When the short element 21b reaches the inner end of the long element 21a, the second member 12 is at about 180 degrees with respect to the first member 11. At this time, the power supply to the linear motor 21 is controlled so that the short element 21b moves radially outward. As a result, the short element 21b starts to slide radially outward along the long element 21a. At this time, the second member 12 continues to rotate in a counterclockwise direction. When the short element 21b slides further, the second member 12 can take the position shown in FIG. 4(b) (4 o'clock position) and the position shown in FIG. 4(c) (2 o'clock position). At this time, the second end 29b of the link member 29 draws a circumferential trajectory t1 (see FIG. 1) centered on the rotation axis 13a, and the first end 29a of the link member 29 draws a linear trajectory t2 (see FIG. 1) along the long element 21a. In other words, the long member 21a, the short member 21b, the fixed member 27, and the link member 29 form a crank mechanism that converts motion between reciprocating linear motion and circular motion.

As described above, in this embodiment, by supplying power to the linear motor 21 having the long member 21a arranged on the first member 11, a moment is generated in the second member 12 around the joint portion 13 via the link member 29, causing a relative rotational movement between the first member 11 and the second member 12. Therefore, compared to a configuration in which a rotational torque is generated near the joint portion 13, it is possible to cause a relative rotational movement between the first member 11 and the second member 12 with a smaller torque. Moreover, because the linear motor 21 is arranged on the first member 11 and is not housed within the joint portion 13, an increase in size of the joint portion 13 can be avoided.

In the robot 10 shown in FIG. 1, the fixed member 27 is fixed to the second member 12, and the second end 29b of the link member 29 is connected to the fixed member 27, but this configuration is not limited to this. For example, the fixed member 27 may be omitted, and the second end 29b of the link member 29 may be directly connected to the second member 12.

Also, as shown in FIG. 5, the fixing member 27 may have an inward extending portion 27c extending from the protruding portion 27b in a direction approaching the joint portion 13, and the link member 29 may be rotatably connected to the tip of this inward extending portion 27c. In this case, the radius of the circular path t1 described by the second end portion 29b of the link member 29 can be reduced. Therefore, the ratio of the rotation angle to the sliding amount of the short shaft 21b can be increased.

In addition, instead of the fixing member 27 having the inward extending portion 27c, the protruding portion 27b may be configured to protrude in the rotation direction from the inner end or the vicinity of the inner end of the long portion 27a.

Second Embodiment
6A to 6C show a second embodiment of the present invention. Note that the same components as those in the first embodiment are given the same reference numerals, and detailed descriptions thereof will be omitted.

In the robot 10 of the first embodiment, the fixed member 27 is configured by a member fixed to the second member 12, whereas in the second embodiment, the fixed member 27 is configured as a second long member member 33 fixed to the second long member 31a of the second linear motor 31 provided on the second member 12.

The second linear motor 31 has a second long element 31a fixed to the second member 12, and a second short element 31b that moves along the second long element 31a due to the action of electromagnetic force caused by the supply of power to the second linear motor 31. The second linear motor 31 has a configuration similar to that of the linear motor 21 shown in FIG. 1, and has multiple armatures and multiple magnetic poles.

The long element 21a of the linear motor 21 is arranged to extend in the radial direction of the rotation axis 13a so as to pass through the rotation axis 13a of the joint 13, and a first long element member 35 is fixed to one end of the long element 21a. The long element 21a may be arranged so that its extension line passes through a position offset from the rotation axis 13a, in which case the first long element member 35 may be omitted.

The second long element 31a has the same configuration as the long element 21a. That is, the second long element 31a is arranged to extend in the radial direction of the rotation axis 13a, and a second long element member 33 is fixed to one end of the second long element 31a. The second long element 31a may be arranged so that its extension line passes through a position offset from the rotation axis 13a, in which case the second long element member 33 may be omitted.

The first end 29a (end on the first member 11 side) of the link member 29 is rotatably connected to the short element 21b of the linear motor 21, and the second end 29b (end on the second member 12 side) of the link member 29 is rotatably connected to the second long element 33. The connection position between the first end 29a of the link member 29 and the short element 21b is arranged so that the extension line of the displacement trajectory t3 when the short element 21b slides passes through a position shifted from the rotation axis 13a, but may be arranged so that the extension line of the displacement trajectory t3 passes through the rotation axis 13a. The second end 29b of the link member 29 may be connected to the second member 12, or may be connected to the second long element 31a of the second linear motor 31. The second end 29b is arranged at a position shifted from the extension line of the second long element 31a, but may be arranged on the extension line of the second long element 31a.

The robot 10 of the second embodiment is provided with a second link member 37 in addition to the link member 29. One end of the second link member 37 (the second end 37b, which is the end on the second member 12 side) is rotatably connected to the second short member 31b. The connection position between the second end 37b of the second link member 37 and the second short member 31b is arranged so that an extension line of the displacement trajectory t4 when the second short member 31b slides passes through a position shifted from the rotation axis 13a, but may be arranged so that an extension line of the displacement trajectory t4 passes through the rotation axis 13a.

The other end of the second link member 37 (first end 37a, which is the end on the first member 11 side) is rotatably connected to the first long member member 35. The first end 37a of the second link member 37 may be connected to the first member 11, or may be connected to the long member 21a of the linear motor 21. The first end 37a is positioned at a position offset from the extension line of the long member 21a, but may also be positioned on the extension line of the long member 21a.

The linear motor 21 and the second linear motor 31 are interlocked. That is, the linear motor 21 and the second linear motor 31 are driven simultaneously when the first member 11 and the second member 12 rotate relative to each other. However, the timing when the short member 21b reverses its sliding direction and the timing when the second short member 31b reverses its sliding direction are shifted from each other. That is, the timing when the link member 29 and the second long member 33 become aligned (the timing when the second short member 31b passes the dead point) and the timing when the second link member 37 and the first long member 35 become aligned (the timing when the short member 21b passes the dead point) are shifted from each other. Therefore, even when one of the link member 29 and the second link member 37 becomes the dead point, the moment around the joint 13 can be continuously generated.

6(a) shows the state where the first member 11 and the second member 12 are almost in a straight line (about 180 degrees), and when bending the second member 12 from this state relative to the first member 11, the short member 21b and the second short member 31b are slid in a direction away from the joint portion 13. As a result, a moment is generated in the first member 11 and the second member 12 about the joint portion 13 in a direction in which the angle formed by the long member 21a and the second long member 31a becomes smaller, and this causes a relative rotational movement between the first member 11 and the second member 12. Then, the position shown in FIG. 6(b) is reached, and when further rotation is made from this position, the second link member 37 and the first long member 35 first become in a straight line, so that the second short member 31b is at a dead point. At this time, the link member 29 and the second long member 33 are not yet in a straight line, so a moment continues to be generated around the joint 13 in the first member 11 and the second member 12. Therefore, the relative rotation between the first member 11 and the second member 12 continues. The second linear motor 31 is power-controlled so that the sliding direction of the second short member 31b is reversed at the timing when the second link member 37 and the first long member 35 are in a straight line.

After that, when the relative rotation between the first member 11 and the second member 12 continues, the link member 29 and the second long member 33 become linear, so that the short member 21b is at the dead center position. At this time, the second link member 37 and the first long member 35 are not linear, so a moment around the joint 13 continues to be generated in the first member 11 and the second member 12. Therefore, the relative rotation between the first member 11 and the second member 12 continues. The linear motor 21 is power-controlled so that the sliding direction of the short member 21b is reversed at the timing when the link member 29 and the second long member 33 become linear. Then, when the short member 21b and the second short member 31b each slide in a direction approaching the joint 35, they assume the posture shown in FIG. 6(c).

In the second embodiment, the linear motor 21 and the second linear motor 31 are used to generate relative rotational motion between the first member 11 and the second member 12, so the torque of each linear motor 21, 31 can be further reduced, and the linear motor 21 can be made smaller.

In addition, the timing when the short member 21b passes the dead point and the timing when the second short member 31b passes the dead point are shifted from each other. That is, when the short member 21b passes the dead point, the second short member 31b is not at the dead point. Also, when the second short member 31b passes the dead point, the short member 21b is not at the dead point. Therefore, even when the short member 21b is at the dead point, the rotational movement between the first member 11 and the second member 12 via the link member 29 can be continued, and even when the second short member 31b is at the dead point, the rotational movement between the first member 11 and the second member 12 via the second link member 37 can be continued. Therefore, the rotational movement between the first member 11 and the second member 12 can be made into a continuous series of movements.

Third Embodiment
7A and 7B show a third embodiment of the present invention, in which the same components as those in the first embodiment are given the same reference numerals and detailed description thereof will be omitted.

The robot 40 of the third embodiment includes a first linear motor 21, a second linear motor 31, and a link member 42. The first linear motor 21 includes a first long element 21a fixed to the first member 11, and a first short element 21b that moves along the first long element 21a with respect to the first long element 21a due to the action of electromagnetic force accompanying the supply of power to the first linear motor 21. The first linear motor 21 has a configuration similar to that of the linear motor 21 shown in FIG. 1, and includes a plurality of armatures 23 and a plurality of magnetic pole elements 24. The first long element 21a has a shape that extends linearly in one direction, and the direction in which the first long element 21a extends may pass through the rotation axis 13a of the joint portion 13, or may be offset from the rotation axis 13a.

The second linear motor 31 has a second long element 31a fixed to the second member 12, and a second short element 31b that moves along the second long element 31a with respect to the second long element 31a due to the action of electromagnetic force accompanying the supply of power to the second linear motor 31. The second linear motor 31 has a configuration similar to that of the linear motor 21 shown in FIG. 1, and has multiple armatures and multiple magnetic poles. The second long element 31a has a shape that extends linearly in one direction, and the direction in which the second long element 31a extends may pass through the rotation axis 13a of the joint portion 13, or may be offset from the rotation axis 13a.

The link member 42 connects the first short member 21b and the second short member 31b. That is, the first end 42a (the end on the first member 11 side) of the link member 42 is rotatably connected to the first short member 21b, and the second end 42b (the end on the second member 12 side) of the link member 42 is rotatably connected to the second short member 31b.

The first linear motor 21 and the second linear motor 31 are linked. That is, the first linear motor 21 and the second linear motor 31 are driven simultaneously when the first member 11 and the second member 12 rotate relatively. When the first short member 21b and the second short member 31b are slid in a direction away from the joint portion 13, a moment is generated in the first member 11 and the second member 12 about the joint portion 13 in a direction in which the angle formed by the first long member 21a and the second long member 31a becomes smaller. This causes a relative rotation between the first member 11 and the second member 12, and the position shown in FIG. 7(a) changes to the position shown in FIG. 7(b).

On the other hand, when the first short element 21b and the second short element 31b are slid toward the joint 13, a moment is generated in the first member 11 and the second member 12 about the joint 13 in a direction in which the angle between the first long element 21a and the second long element 31a increases. This causes a relative rotational movement between the first member 11 and the second member 12, changing the position shown in FIG. 7(b) to the position shown in FIG. 7(a).

In the third embodiment, when the first short member 21b and the second short member 31b are slid by supplying power to the first linear motor 21 and the second linear motor 31, a force that changes the opening angle between the first member 11 and the second member 12 is applied by the link member 42, thereby causing a relative rotational movement between the first member 11 and the second member 12. Therefore, compared to a configuration in which a rotational torque is generated near the joint portion 13, it is possible to cause a relative rotational movement between the first member 11 and the second member 12 with a smaller torque. Moreover, since the linear motor 21 is disposed on the first member 11 and the second linear motor 31 is disposed on the second member 12, and the two linear motors 21 are not housed within the joint portion 13, the joint portion 13 can be prevented from becoming large.

Note that the explanation of other configurations, actions, and effects will be omitted, but the explanations of the first and second embodiments can be applied to the third embodiment.

Fourth Embodiment
8A shows a fourth embodiment of the present invention, in which the same components as those in the third embodiment are given the same reference numerals and detailed description thereof will be omitted.

In the robot 40 of the third embodiment, the first long element 21a is fixed to the first member 11 so as not to be displaced relative to the first member 11, and the second long element 31a is fixed to the second member 12 so as not to be displaced relative to the second member 12. In contrast, in the robot 40 of the fourth embodiment, the first long element 21a is arranged slidably relative to the first member 11, and the second long element 31a is arranged slidably relative to the second member 12. In other words, the first long element 21a is supported by the first member 11 so as to be displaceable in the extension direction of the first long element 21a, and the second long element 31a is supported by the second member 12 so as to be displaceable in the extension direction of the second long element 31a.

The first member 11 is provided with a first guide portion 45 that allows the first elongated element 21a to move in the extension direction of the first elongated element 21a while preventing it from moving in a direction perpendicular to the extension direction of the first elongated element 21a, and the second member 12 is provided with a second guide portion 46 that allows the second elongated element 31a to move in the extension direction of the second elongated element 31a while preventing it from moving in a direction perpendicular to the extension direction of the second elongated element 31a.

The first long element 21a and the second long element 31a have multiple teeth 21c, 31c aligned in the longitudinal direction. A pinion 47 that meshes with the multiple teeth 21c of the first long element 21a and the multiple teeth 31c of the second long element 31a is provided in the joint portion 13 concentrically with the rotation axis 13a. The pinion 47 is provided so as to be freely rotatable.

The first short piece 21b is provided with a first short piece brake 49 that temporarily fixes the first short piece 21b to the first member 11, and the second short piece 31b is provided with a second short piece brake 50 that temporarily fixes the second short piece 31b to the second member 12. That is, the first short piece brake 49 is configured to be able to switch the first short piece 21b between a state in which it is fixed to the first member 11 and a state in which it is not fixed. The second short piece brake 50 is configured to be able to switch the second short piece 31b between a state in which it is fixed to the second member 12 and a state in which it is not fixed.

The first long element 21a is provided with a first long element brake 51 that temporarily fixes the first long element 21a to the first member 11, and the second long element 31a is provided with a second long element brake 52 that temporarily fixes the second long element 31a to the second member 12. In other words, the first long element brake 51 is configured to be able to switch between a state in which the first long element 21a is fixed to the first member 11 and a state in which it is not fixed. The second long element brake 52 is configured to be able to switch between a state in which the second long element 31a is fixed to the second member 12 and a state in which it is not fixed.

In a state where the first long element brake 51 is actuated to fix the first long element 21a to the first member 11 and the first short element brake 49 is not actuated to not fix the first short element 21b, and the second long element brake 52 is actuated to fix the second long element 31a to the second member 12 and the second short element brake 50 is not actuated to not fix the second short element 31b, the robot 40 of the fourth embodiment operates in the same manner as the robot 40 of the third embodiment. Therefore, when the first short element 21b and the second short element 31b each slide in a direction away from the joint portion 13, a relative rotational movement occurs between the first member 11 and the second member 12 in a direction in which the second member 12 is bent more relative to the first member 11, as shown in Figures 8(a) and 8(b).

8(a), when the first short element brake 49 and the second short element brake 50 are activated while the first long element brake 51 and the second long element brake 52 are switched to an inoperative state, the first short element 21b is fixed to the first member 11 and the second short element 31b is fixed to the second member 12, and the first long element 21a and the second long element 31a are slidable. In this state, when power is supplied to the first linear motor 21 and the second linear motor 31, the first long element 21a slides relative to the first short element 21b and the first member 11, and the second long element 31a slides relative to the second short element 31b and the second member 12. As a result, a moment of rotation about the joint portion 13 is generated in the first member 11 and the second member 12 via the link member 42. For example, when the first long element 21a and the second long element 31a each slide toward the joint portion 13 (the pinion 47), a force acts to press the second short element 31b against the link member 42. Therefore, a reaction force is generated that includes a component that presses the second long element 31a downward in FIG. 8(a). As a result, the second member 12 rotates clockwise from the state in FIG. 8(a). This brings the robot 40 to the state shown in FIG. 9. At this time, because the first long element 21a and the second long element 31a have slid from the state in FIG. 8(a), the range of movement of the first short element 21b and the second short element 31b is expanded.

Therefore, in the fourth embodiment, the first long element 21a slides in the longitudinal direction and the second long element 31a slides in the longitudinal direction, thereby widening the range of movement of the first short element 21b. Therefore, the relative rotation range between the first member 11 and the second member 12 can be widened.

Note that the explanation of other configurations, actions, and effects will be omitted, but the explanations of the first to third embodiments can be applied to the fourth embodiment.

Fifth Embodiment
10A and 10B show a fifth embodiment of the present invention, in which the same components as those in the first embodiment are given the same reference numerals and detailed description thereof will be omitted.

In the robot 40 of the third embodiment, the first short member 21b and the second short member 31b are connected by a link member 42, and by sliding the first short member 21b and the second short member 31b, a moment is generated in the second member 12 around the joint portion 13. This operation is similar to that of the robot 60 of the fifth embodiment. Furthermore, in the robot 60 of the fifth embodiment, a pinion 62 that rotates due to the sliding of the first long member 21a of the first linear motor 21 rotates a rotating member 64 fixed to the second member 12, thereby generating a relative rotational movement between the first member 11 and the second member 12.

Specifically, unlike the third embodiment, the first long element 21a is not fixed to the first member 11, but is arranged to be slidable relative to the first member 11 in the extension direction of the first long element 21a, as in the fourth embodiment. The first long element 21a is provided with a long element brake 51 that temporarily fixes the first long element 21a to the first member 11. The first long element 21a is also provided with a plurality of teeth 21c aligned in the extension direction. Meanwhile, the first short element 21b is provided with a short element brake 49 that temporarily fixes the first short element 21b to the first member 11.

The first member 11 is provided with a pinion 62 that meshes with the teeth 21c of the first long element 21a, and this pinion 62 rotates as the first long element 21a slides.

The joint portion 13 is provided with a rotating member 64 having an arc-shaped outer periphery, and the outer periphery of the rotating member 64 is formed with teeth 64a that mesh with the pinion 62.

Therefore, when power is supplied to the first linear motor 21 with the short-length brake 49 operating and the long-length brake 51 not operating, the first long-length member 21a slides relative to the first short-length member 21b, and the pinion 62 rotates accordingly. At this time, it is not necessary to supply power to the second linear motor 31. When the pinion 62 rotates, the rotating member 64 rotates around the rotation axis 13a of the joint portion 13, so that the second member 12 rotates relative to the first member 11. Therefore, the second member 12 can be rotated from the state shown in FIG. 10(a) to the state shown in FIG. 10(b).

On the other hand, when power is supplied to the first linear motor 21 and the second linear motor 31 with the long element brake 51 operating and the short element brake 49 not operating, the first short element 21b slides relative to the first long element 21a, and the second short element 31b slides relative to the second long element 31a. In this case, the second member 12 is rotated relative to the first member 11 using the same principle as in the third embodiment. Therefore, the second member 12 can be rotated from the state shown in FIG. 10(a) to the state shown in FIG. 10(c).

In the fifth embodiment, when power is supplied to the first linear motor 21 with the first short member 21b fixed to the first member, a moment is generated in the second member 12 around the joint 13 via the pinion 62 and the rotating member 64, causing a relative rotational movement between the first member 11 and the second member 12. When power is supplied to the first linear motor 21 and the second linear motor 31 with the first long member 21a fixed to the first member 11 and the first short member 21b not fixed, a moment is generated in the second member 12 around the joint 13 via the link member 42 due to the sliding of the first short member 21b and the second short member 31b, causing a relative rotational movement between the first member 11 and the second member 12. The first linear motor 21 is disposed on the first member 11 and is not housed within the joint 13, and the second linear motor 31 is disposed on the second member 12 and is not housed within the joint 13, which prevents the joint 13 from becoming too large.

Note that the explanation of other configurations, actions, and effects will be omitted, but the explanations of the first and second embodiments can be applied to the fifth embodiment.

10: Robot 11: First member 12: Second member 13: Joint portion 13a: Rotation axis 21: First linear motor 21: Direct motor 21a: First long piece 21a: Long piece 21b: First short piece 21b: Short piece 21c: Tooth portion 27: Fixed member 29: Link member 29a :First end 29b :Second end 31 :Second linear motor 31a :Second long element 31b :Second short element 31c :Tooth part 37 :Second link member 37a :First end 37b :Second End 40: Robot 42: Link member 42a: First end 42b: Second end 47: Pinion 49 : First movable brake 50 : Second movable brake 51 : First fixed brake 52 : Second fixed brake 60 : Robot 62 : Pinion 64 : Rotating member 64a : Tooth portion

Claims (5)

A first member;
A second member; and
a joint portion that rotatably couples the first member and the second member to each other;
a first linear motor having a first long element extending along a direction in which the first member extends and disposed on the first member, and a first short element movable along the first long element;
a first link member having one end rotatably connected directly or indirectly to the second member and another end rotatably connected to the first short member;
A fixing member having a shape extending in one direction is fixed to the second member,
The one end of the first link member is pivotally coupled to the fixed member,
the fixed member is constituted by a second long element of a second linear motor having a second long element and a second short element, or is constituted by a second long element member fixed to the second long element,
The second elongated element is formed in a shape extending along the extension direction of the second member,
a second link member having one end rotatably connected to the second short element and the other end rotatably connected to the first long element or a first long element member fixed to the first long element;
A robot in which the first short element is moved relative to the first long element by supplying power to the first linear motor, thereby generating a moment around the joint in the second member via the first link member, causing a relative rotational movement between the first member and the second member, and the second short element is moved along the second long element by supplying power to the second linear motor, thereby generating a moment around the joint in the first member via the second link member, thereby causing a relative rotational movement between the first member and the second member. A first member;
A second member;
a joint portion that rotatably couples the first member and the second member to each other;
a first linear motor having a first long element that is shaped to extend in one direction and that is disposed on the first member, and a first short element that is movable along the first long element;
a first link member having one end rotatably connected directly or indirectly to the second member and another end rotatably connected to the first short member;
A fixing member having a shape extending in one direction is fixed to the second member,
The one end of the first link member is rotatably coupled to the fixed member,
the fixed member is constituted by a second long element of a second linear motor having a second long element and a second short element, or is constituted by a second long element member fixed to the second long element,
a second link member having one end rotatably connected to the second short element and the other end rotatably connected to the first long element or a first long element member fixed to the first long element;
supplying power to the first linear motor to move the first short element along the first long element, thereby generating a moment around the joint in the second member via the first link member, and supplying power to the second linear motor to move the second short element along the second long element, thereby generating a moment around the joint in the first member via the second link member, thereby generating a relative rotational movement between the first member and the second member;
The robot is configured so that a timing at which the first short element passes through the dead point is shifted from a timing at which the second short element passes through the dead point. A first member;
A second member; and
a joint portion that rotatably couples the first member and the second member to each other;
a first linear motor including a first long element having a portion extending along the first member and disposed on the first member, and a first short element movable relative to the first long element along the portion of the first long element;
a second linear motor including a second long element having a portion extending along the second member, and a second short element movable relative to the second long element along the portion of the second long element;
a link member having one end rotatably connected to the first short member and another end rotatably connected to the second short member,
A robot in which, by supplying power to the first linear motor and the second linear motor, the first short element moves relative to the first long element and the second short element moves relative to the second long element, thereby causing relative rotational movement between the first member and the second member. A first member;
A second member;
a joint portion that rotatably couples the first member and the second member to each other;
a first linear motor including a first long element having a portion extending in one direction and disposed on the first member, and a first short element movable relative to the first long element along the portion of the first long element;
a second linear motor including a second long element having a portion extending along the second member, and a second short element movable relative to the second long element along the portion of the second long element;
a link member having one end rotatably connected to the first short member and another end rotatably connected to the second short member,
When power is supplied to the first linear motor and the second linear motor, the first short element moves relative to the first long element and the second short element moves relative to the second long element, thereby generating a relative rotational movement between the first member and the second member.
a first short member brake capable of switching the first short member between a state in which the first short member is fixed to the first member and a state in which the first short member is not fixed to the first member;
a second short member brake capable of switching the second short member between a state in which the second short member is fixed to the second member and a state in which the second short member is not fixed to the second member;
The first elongated element is supported so as to be displaceable in an extending direction of the first elongated element,
The second elongated element is supported so as to be displaceable in an extending direction of the second elongated element. The robot according to claim 4,
The first elongated element and the second elongated element have a plurality of teeth arranged in a longitudinal direction,
A robot comprising a pinion that meshes with the plurality of teeth of the first elongated element and the plurality of teeth of the second elongated element.