JP6934244B2 - Telescopic robot arm - Google Patents

Description

The present invention relates to a telescopic robot arm.

A robot arm is required as a camera drive device for observing molten nuclear fuel in a nuclear power plant after a severe accident.

FIG. 15 is a front view showing a conventional robot arm (see: Fig. 1 (a) of Non-Patent Document 1). The robot arm of FIG. 15 is an articulated arm and shows a horizontally extended posture that is most susceptible to gravity. In FIG. 15, a large number of links 101-1, 101-2, ... (Only three are shown) are serially connected by horizontal joints 102-1, 102-2, ... And guided to the base 103. There is. It is driven by driving an actuator (motor) (not shown) provided in each of the joints 102-1, 102-2, .... In this case, the camera 106 is provided on the link on the tip side, for example, 101-4.

In the conventional robot arm of FIG. 15, the degree of freedom of bending of each joint 102-1, 102-2, ... Is large, and therefore the total displacement amount of the robot arm is also large.

Shigeo Hirose, Shone Ma: Development of Wire Interference Driven Robot Arm, Proceedings of the Society of Instrument and Control Engineers, 26-11, 1291/1298 (1990)

However, in the conventional robot arm shown in FIG. 15, the thickness of each link is the same and each joint is provided with an actuator. Therefore, when the number of joints increases, the weight of the robot arm becomes excessive due to the link and the actuator. There is a problem that it becomes. Further, when the robot arm is held horizontally or diagonally, an actuator drive is required, so that there is also a problem that power consumption is large.

In order to solve the above-mentioned problems, the telescopic robot arm according to the present invention includes a base, an outer cylinder fixed to the base, an inner cylinder inserted in the outer cylinder, and an outer cylinder and an inner cylinder. A plurality of intermediate cylinders inserted between the two, a telescopic actuator fixed to the base for linearly moving and deploying the intermediate cylinder and the inner cylinder with respect to the outer cylinder, and at least one wire and a base. A first that is fixed to a table and has a bending actuator for adjusting the tension of the wire to bend the outer cylinder, the intermediate cylinder and the inner cylinder, and one pulley provided at the tip of the outer cylinder for guiding the wire. It comprises a pulley mechanism and the only second pulley mechanism provided at the tip of the intermediate cylinder and having one pulley for guiding the wire, the wire being fixed to the bending actuator and first from the bending actuator. It is wound around the pulley of one pulley mechanism of the plurality of second pulley mechanisms via the pulley mechanism of the plurality of second pulley mechanisms, and is folded back from the pulley of one pulley mechanism of the plurality of second pulley mechanisms. It is wound around one pulley, folded back from the one pulley of the first pulley mechanism, and wound around the pulleys of the other pulley mechanisms of the plurality of second pulley mechanisms, and the other of the plurality of second pulley mechanisms. It is folded back from the pulley of the pulley mechanism, wound around another pulley of the first pulley mechanism, folded back from the other pulley of the first pulley mechanism, and fixed to the tip of the inner cylinder.

According to the present invention, the weight can be reduced by adopting a telescopic arm in which the cylinder becomes thinner toward the tip side and no rotary joint is required, and the degree of freedom of bending of the robot arm can be maintained by the wire. Further, since each telescopic type cylinder structurally has a cantilever mechanism, power consumption is not required when the robot arm is held horizontally or diagonally.

It is a front view which shows the stored state of the 1st Embodiment of the telescopic type robot arm which concerns on this invention. It is a front view which shows the deployed state of the telescopic type robot arm of FIG. 1, (A) shows a non-bent state, and (B) shows a bent state. It is a front view which shows the stored state of the 2nd Embodiment of the telescopic type robot arm which concerns on this invention. 3 is a front view showing a deployed state of the telescopic robot arm of FIG. 3, where FIG. 3A shows a non-bent state and FIG. 3B shows a bent state. It is a perspective view which shows the guide of FIG. 3 and FIG. It is a perspective view which shows the pulley mechanism instead of the guide of FIG. 5 is a perspective view showing a modified example of the guide and pulley mechanisms of FIGS. 5 and 6. It is a front view which shows the stored state of the 3rd Embodiment of the telescopic type robot arm which concerns on this invention. 8 is a front view showing a deployed state of the telescopic robot arm of FIG. 8, where FIG. 8A shows a non-bent state and FIG. 8B shows a bent state. 8 is a diagram schematically showing a wire and pulley mechanism of FIGS. 8 and 9. A first example of the pulley mechanism 21 "a of FIG. 10 is shown, (A) is a perspective view, (B) is a front view, and (C) is a side view. A second example of the pulley mechanism 21 "a of FIG. 10 is shown, (A) is a perspective view, (B) is a front view, and (C) is a side view. A third example of the pulley mechanism 21 "a of FIG. 10 is shown, (A) is a perspective view, (B) is a front view, and (C) is a side view. A fourth example of the pulley mechanism 21 "a of FIG. 10 is shown, (A) is a perspective view, (B) is a front view, and (C) is a side view. It is a front view which shows the conventional robot arm.

FIG. 1 is a front view showing a stored state of the first embodiment of the telescopic robot arm according to the present invention.

In FIG. 1, an outer cylinder 21 is fixed to a base 1 in which a control unit (not shown) is built, an inner cylinder 22 is inserted into the outer cylinder 21, and an inner cylinder 22 is inserted between the outer cylinder 21 and the inner cylinder 22. At least one intermediate cylinder 23 is inserted. A camera 3 is provided at the tip of the inner cylinder 22. In FIG. 1, the number of intermediate cylinders 23 is three, but other numbers can be used. The outer cylinder 21, the intermediate cylinder 23, and the inner cylinder 22 form a telescopic mechanism 2 that becomes thinner toward the tip side, and expands and contracts by linearly moving in the radial direction R by an actuator (motor, hydraulic cylinder, etc.) (not shown). One end of the wire 4 is connected to the tip of the inner cylinder 22, and the other end of the wire 4 is connected to the actuator (motor) 5 fixed to the base 1, whereby the tension of the wire 4 is adjusted by the actuator 5. NS.

Further, the outer cylinder 21 is rotatably supported in the angular direction φ by an actuator (not shown) on the support rod 6, and the support rod 6 is rotatably supported in the angular direction θ by an actuator (not shown) on the moving table 7.

2A and 2B are front views showing the deployed state of the telescopic robot arm of FIG. 1, where FIG. 2A shows a non-bent state and FIG. 2B shows a bent state.

First, when the telescopic mechanism 2 is linearly moved in the radial direction R by an actuator (not shown) built in the base 1 and deployed, as shown in FIG. 2A, the cylinders 21, 23, and 22 of the telescopic mechanism 2 are Since it is structurally a cantilever mechanism, the robot arm can be held horizontally or diagonally without requiring power consumption.

Next, when the wire 4 is wound up by the actuator 5, as shown in FIG. 2B, the cylinders 21, 23, and 22 of the telescopic mechanism 2 bend upward due to the tension of the wire 4. However, in this case, in particular, since the inner cylinder 22 having a small diameter is directly driven by the wire 4, only the inner cylinder 22 having a small moment of inertia of area is greatly bent. The bending of the cylinder 23 is very small, and the bending of the inner cylinder 22 on the tip side is remarkable. As a result, the total displacement of the robot arm is relatively small.

As described above, the telescopic robot arm of FIGS. 1 and 2 can maintain the degree of freedom of bending by expanding and contracting the wire 4.

In addition, in FIGS. 1 and 2, the actuator (motor) 5 is fixed to the upper part of the base 1, but another actuator fixed to the outside of the base 1, for example, the lower part is provided, and the inner cylinder 22 and the actuator (motor) 5 are provided. A wire may be provided between the actuator and the other actuator. That is, two or more actuators and wires may be provided, respectively. As a result, the degree of freedom of bending of the robot arm can be increased.

FIG. 3 is a front view showing a stored state of the second embodiment of the telescopic robot arm according to the present invention.

In FIG. 3, guides 21a and 23a are provided on the outer cylinder 21 and the intermediate cylinder 23 in order to guide the wire 4. Although one guide 21a and 23a are provided on the outer cylinder 21 and each intermediate cylinder 23, it is not necessary to provide the guides 21a and 23a on all of the outer cylinder 21 and the intermediate cylinder 23, and at least one guide 21a and 23a may be provided. A plurality of 21 and the intermediate cylinder 23 may be provided.

4A and 4B are front views showing the deployed state of the telescopic robot arm of FIG. 3, where FIG. 4A shows a non-bent state and FIG. 4B shows a bent state.

First, when the telescopic mechanism 2 is linearly moved in the radial direction R by an actuator (not shown) built in the base 1 and deployed, as shown in FIG. 4A, the cylinders 21, 23, and 22 of the telescopic mechanism 2 are Since it is structurally a cantilever mechanism, the robot arm can be held horizontally or diagonally without requiring power consumption. At this time, the wires 4 are present along the outer cylinder 21, the intermediate cylinder 23, and the inner cylinder 22 of the telescopic mechanism 2 by the guides 21a and 23a.

Next, when the wire 4 is wound up by the actuator 5, as shown in FIG. 4B, the wire 4 exists along the outer cylinder 21, the intermediate cylinder 23, and the inner cylinder 22, and is therefore constant with respect to the telescopic mechanism 2. Generates the bending moment of. Therefore, also in this case, the respective cylinders 21, 23, and 22 of the telescopic mechanism 2 are bent upward, but the outer cylinder 21 and the intermediate cylinder 23 on the root side are slightly bent, and the inner cylinder 22 having a small diameter is bent upward. It becomes remarkable. However, since the wire length that contributes to bending is short, the amount of bending is small and fine adjustment is possible. As in the case of (B) of FIG. 2, the total displacement amount of the robot arm is small.

As described above, the telescopic robot arm of FIGS. 3 and 4 can maintain the degree of freedom of bending by expanding and contracting the wire 4, and can finely adjust the position of the inner cylinder 22, that is, the position of the camera 3.

FIG. 5 shows an example of the guides 21a (23a) of FIGS. 3 and 4. In FIG. 5, 211 is a cylinder hole and 212 is a wire hole. Instead of the guide 21a (23a), the pulley mechanism 21'a (23'a) shown in FIG. 6 may be used. In FIG. 6, 211'is a cylinder hole and 212' is a wire winding pulley. Further, in FIGS. 3 and 4, the actuator (motor) 5 is fixed inside the base 1, but another actuator is provided inside the base 1 between the inner cylinder 22 and the other actuator. A wire may be provided in the. For example, when a total of three actuators and a total of three wires are provided, the guide 21a (23a) shown in FIG. 7A or the pulley mechanism 21'a (23'a) shown in FIG. 7B is provided. ) Is used.

FIG. 8 is a front view showing a stored state of the third embodiment of the telescopic robot arm according to the present invention.

In FIG. 8, pulley mechanisms 21 "a, 23'a (see FIG. 9) are provided on the outer cylinder 21 and the intermediate cylinder 23 in order to guide the wires 4-1, 4-2, and 4-3. In this case, the pulley mechanism 21 "a has three pulleys for each wire 4-1, 4-2, 4-3, whereas the pulley mechanism 23'a is the same as in the case of FIG. 7B. Has one pulley for each wire 4-1, 4-2, 4-3. The pulley mechanism 21'a may be provided in at least one intermediate cylinder 23. The pulley mechanism 21 "a will be described later.

9 is a front view showing the deployed state of the telescopic robot arm of FIG. 8, where FIG. 9A shows a non-bent state and FIG. 9B shows a bent state.

First, when the telescopic mechanism 2 is linearly moved in the radial direction R by an actuator (not shown) built in the base 1 and deployed, as shown in FIG. 9A, the cylinders 21, 23, and 22 of the telescopic mechanism 2 are Since it is structurally a cantilever mechanism, the robot arm can be held horizontally or diagonally without requiring power consumption. At this time, the wires 4-1, 4-2, and 4-3 are present along the outer cylinder 21, the intermediate cylinder 23, and the inner cylinder 22 of the telescopic mechanism 2 by the pulley mechanisms 21 "a, 23'a.

Next, when the wire 4-1 is wound up by the actuator 5-1 as shown in FIG. 9B, the wire 4-1 is formed into the intermediate cylinder 23 by folding back the pulley mechanism 23'a from the pulley mechanism 21 "a. A bending moment is generated, and as a result, the intermediate cylinder 23 also bends greatly upward. Further, the wire 4-1 is folded back from the pulley mechanism 21 "a to the inner cylinder 22 to generate a bending moment in the inner cylinder 22, and as a result, this result. , The inner cylinder 22 also bends greatly upward. That is, the intermediate cylinder 23 and the inner cylinder 22 all bend upward greatly. Therefore, the total displacement amount of the robot arm can be increased as compared with the first embodiment of FIGS. 1 and 2 and the second embodiment of FIGS. 3 and 4.

FIG. 10 is a diagram showing the relationship between the wire and pulley mechanisms of FIGS. 8 and 9. In FIG. 10, the intermediate cylinder 23 is three intermediate cylinders 23-1, 23-2, 23-3, and the pulley mechanisms fixed to these are 23'a-1, 23'a-2, 23'. Let it be a-3. Although the intermediate cylinder 23 and the inner cylinder 22 in FIG. 10 are tapered cylinders, they may be ordinary cylinders.

As shown in FIG. 10, the wire 4-1 is fixed to the outer cylinder 21 by folding back the pulley 213'-1 of the pulley mechanism 23'a-1 fixed to the intermediate cylinder 23-1 from the actuator 5-1. The pulley mechanism 23'a-2 is wound around the pulley 212 "-1 of the pulley mechanism 21" a, folded back from the pulley 212'-1 of the pulley mechanism 21 "a, and then fixed to the intermediate cylinder 23-2. The pulley 213'-2 is folded back and wound around the pulley 212 "-2 of the pulley mechanism 21" a-2 fixed to the outer cylinder 21, and further from the pulley 212 "-2 of the pulley mechanism 21" a-2. After being folded back, the pulley 213'-3 of the pulley mechanism 23'a-3 fixed to the intermediate cylinder 23-3 is folded back and wound around the pulley 212 "-3 of the pulley mechanism 21" a fixed to the outer cylinder 21. Finally, the wire 4-1 is folded back from the pulley 212 "-3 of the pulley mechanism 21" a and then fixed to the tip of the inner cylinder 22. That is, the wire 4-1 is connected to the pulley mechanism 21 "a" on the way from the actuator 5-1. It is folded back between the pulley mechanism 23'a -1, 23'a-2, and 23'a-3, and finally fixed to the tip of the inner cylinder 22.

Similarly, the wire 4-2 is folded back from the actuator 5-2 between the pulley mechanism 21 "a and the pulley mechanisms 23'a-1, 23'a-2, 23'a-3, and the tip of the inner cylinder 22 is formed. The wire 4-3 is folded back from the actuator 5-3 between the pulley mechanism 21 "a and the pulley mechanisms 23'a-1, 23'a-2, 23'a-3 to form an inner cylinder. It is fixed to the tip of 22.

As described above, the pulley mechanism 21 "a fixed to the outer cylinder 21 has 3 × 3 (= 9) pulleys, and the pulley mechanism fixed to the intermediate cylinders 23-1, 23-2, 23-3. The 23'a-1, 23'a-2, and 23'a-3 have three pulleys. The pulley mechanism 23'a- fixed to the intermediate cylinders 23-1, 23-2, and 23-3. As described above, 1, 23'a-2 and 23'a-3 have the same structure as the pulley mechanism shown in FIG. 7B.

Next, an example of the pulley mechanism 21 "a of FIGS. 9 and 10 will be described.

11A and 11B show a first example of the pulley mechanism 21 "a of FIGS. 9 and 10, FIG. 11A is a perspective view, FIG. 11B is a front view, and FIG. 11C is a side view.

As shown in FIG. 11, an outer cylinder hole 211 "is provided in the center, and wire 4-1 pulleys 212" -1, 212 "-2, 212" -3, and wires 4 are provided in the circumferential direction of the pulley mechanism 21 "a. -2 pulleys 212 "-1, 212" -2, 212 "-3 and wire 4-3 pulleys 212" -1, 212 "-2, 212" -3 are provided. However, as shown in FIG. 11, When the pulley is provided in the circumferential direction of the pulley mechanism 21 "a, a force in the twisting direction of the pulley mechanism 21" a is generated.

12A and 9B show a second example of the pulley mechanism 21 "a of FIGS. 9 and 10, FIG. 12A is a perspective view, FIG. 12B is a front view, and FIG. 12C is a side view.

As shown in FIG. 12, an outer cylinder hole 211 "is provided in the center, and wire 4-1 pulleys 212" -1, 212 "-2, 212" -3, and wires 4 are provided in the radial direction of the pulley mechanism 21 "a. -2 pulleys 212 "-1, 212" -2, 212 "-3 and wire 4-3 pulleys 212" -1, 212 "-2, 212" -3 are provided. However, as shown in FIG. 12, If a pulley is provided in the radial direction of the pulley mechanism 21 "a, the outermost diameter of the telescopic robot arm becomes large.

13 shows a third example of the pulley mechanism 21 "a of FIGS. 9 and 10, (A) is a perspective view, (B) is a front view, and (C) is a side view.

As shown in FIG. 13, an outer cylinder hole 211 "is provided in the center, and wire 4-1 pulleys 212" -1, 212 "-2, 212" -3 are provided in the axial direction of the pulley mechanism 21 "a at equal intervals. , Wire 4-2 pulleys 212 "-1, 212" -2, 212 "-3, and wire 4-3 pulleys 212" -1, 212 "-2, 212" -3 are provided. As shown, if the pulley is provided in the axial direction of the pulley mechanism 21 "a, the wires interfere with each other.

14 shows a fourth example of the pulley mechanism 21 "a of FIGS. 9 and 10, (A) is a perspective view, (B) is a front view, and (C) is a side view.

As shown in FIG. 14, as in the case of FIG. 13, the outer cylinder hole 211 ”is provided in the center, and the wire is inclined in the axial direction of the pulley mechanism 21” a at equal intervals and toward the tip of the robot arm. 4-1 pulley 212 "-1, 212" -2, 212 "-3, wire 4-2 pulley 212" -1, 212 "-2, 212" -3, wire 4-3 pulley 212 "- 1, 212 "-2, 212" -3 are provided.

In the above-described embodiment, the outer cylinder 21, the intermediate cylinder 23, and the inner cylinder 22 are made of the same material, but may be made of a material whose rigidity decreases from the tip side to the root side. good. That is, the rigidity of the outer cylinder 21 and the intermediate cylinder 23 on the base 1 side is made smaller than the rigidity of the inner cylinder 22. As a result, the total displacement amount of the robot arm can be increased.

The present invention may also be applied to any modification of the obvious scope of the embodiments described above.

The present invention can also be used as a robot arm for aerial work other than a camera drive device for observing nuclear fuel in a nuclear power plant.

1: Base 2: Telescopic mechanism 21: Outer cylinder 22: Inner cylinder 23: Intermediate cylinder 21a, 23a: Guides 21'a, 23'a, 23'a-1, 23'a-2, 23'a-3 : Pulley mechanism 21 "a: Pulley mechanism 3: Camera 4, 4-1, 4-2, 4-3: Wire 5, 5-1: Actuator 6: Support rod 7: Moving table 101-1, 101-2, 101-3, ...: Links 102-1, 102-2, 102-3, ...: Joints 103: Bases 104-1, 104-2, ...: Pulleys 105-1, 105-2, 105-3, ... : Wire 106: Camera

Claims (6)

Base and
The outer cylinder fixed to the base and
The inner cylinder inserted into the outer cylinder and
A plurality of intermediate cylinders interpolated between the outer cylinder and the inner cylinder,
An expansion / contraction actuator fixed to the base for linearly moving and deploying the intermediate cylinder and the inner cylinder with respect to the outer cylinder.
With at least one wire,
A bending actuator fixed to the base and for adjusting the tension of the wire to bend the outer cylinder, the intermediate cylinder, and the inner cylinder.
A first pulley mechanism provided at the tip of the outer cylinder and having a plurality of pulleys for guiding the wire, and a first pulley mechanism.
A plurality of second pulley mechanisms provided at the tip of each intermediate cylinder and having one pulley for guiding the wire are provided.
The wire
Fixed to the bending actuator
The bending actuator is wound around the pulley of one pulley mechanism of the plurality of second pulley mechanisms via the first pulley mechanism.
It is folded back from the pulley of one pulley mechanism of the plurality of second pulley mechanisms and wound around one pulley of the first pulley mechanism.
It is folded back from the one pulley of the first pulley mechanism and wound around the pulleys of the other pulley mechanisms of the plurality of second pulley mechanisms.
It is folded back from the pulleys of the other pulley mechanisms of the plurality of second pulley mechanisms and wound around the other pulleys of the first pulley mechanism.
A telescopic robot arm that is folded back from the other pulley of the first pulley mechanism and fixed to the tip of the inner cylinder. The telescopic robot arm according to claim 1 , wherein the plurality of pulleys of the first pulley mechanism are provided in the circumferential direction of the first pulley mechanism. The telescopic robot arm according to claim 1 , wherein the plurality of pulleys of the first pulley mechanism are provided in the radial direction of the first pulley mechanism. The telescopic robot arm according to claim 1 , wherein the plurality of pulleys of the first pulley mechanism are provided in the axial direction of the first pulley mechanism. The telescopic robot arm according to claim 1 , wherein the plurality of pulleys of the first pulley mechanism are provided so as to be inclined in the axial direction of the first pulley mechanism and toward the tip of the robot arm. The telescopic robot arm according to claim 1 , wherein the rigidity of the outer cylinder, the intermediate cylinder, and the inner cylinder is smaller toward the base side.

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