JP2009190156A - Joint lock mechanism of robot - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a joint lock mechanism of a robot, fixing a joint section without actuating a drive unit in a state of robot idling in an upright posture. <P>SOLUTION: The joint lock mechanism of the robot comprises: upper and lower frame members 2, 3 interposing the joint section; a coupling mechanism 4 rotatably connecting the upper and lower frame members 2, 3; a drive unit 5, such as a motor, disposed on one of the upper and lower frame members; and a link mechanism 6 rotatably connecting a first arm 7 and a second arm 8, with an end of one of the arms connected to the drive unit and an end portion of the other arm rotatably connected to the other frame member. The link mechanism 6 is put in an excessively opened state when fixing the joint section, wherein a positioning block 10 disposed standing on one of the first and second arms catches the other arm, and supports the dead weight of the robot's component member existing above the joint section. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a joint lock mechanism of a robot, and more particularly to a mechanism that locks a joint that acts on its own weight such as an ankle joint of a robot.

  2. Description of the Related Art Conventionally, a knee, an ankle, and a hip joint are bent by a driving device such as a motor in an ankle joint of a robot. However, the knees, ankles, and hip joints could not be fixed unless the drive device was operated even when the robot was idling while standing upright.

  Therefore, in order to extend the action time including the waiting time of the robot, it is necessary to increase the capacity of the battery, but conversely, it suffers from a contradiction due to an increase in the output of the driving device due to an increase in the weight of the battery.

  By the way, in Patent Document 1, in the boarding robot, when the seat is lowered to a position where a person can board, the upper frame material is placed on a stopper provided on the lower frame material, and the upper frame A technique for fixing a joint portion between a material and a lower frame material is disclosed.

  Patent Document 2 discloses a technique for maintaining an arm posture by an arm posture maintaining means in a transfer robot.

Further, in Patent Documents 3 to 5, in a holding device that holds a cover member or the like, the first arm and the second arm are fixed in an over-open state when the cover member is opened. A technique for holding a cover member between an arm and a second arm is disclosed.
JP 2006-150568 A JP 2006-26848 A Japanese Utility Model Publication No. 57-80445 Japanese Utility Model Publication 5-31183 JP-A-9-125789

  Thus, at present, in the idling state where the robot is standing upright, the joint lock mechanism of the robot that can fix the joint without operating the driving device cannot be observed.

  An object of the present invention is to provide a joint lock mechanism of a robot that can fix a joint portion without operating a drive device in an idling state where the robot is standing upright.

  The joint lock mechanism of the robot according to the present invention is a mechanism for locking a joint portion to which its own weight acts such as an ankle joint of the robot, and includes an upper frame material, an upper frame material, and a lower frame sandwiching the joint portion. A coupling mechanism that rotatably couples the frame material, a drive device such as a motor provided on one of the upper and lower frame materials, a first arm, and a second arm are rotatably coupled. An end portion of one arm is connected to the drive device, and an end portion of the other arm is rotatably connected to a frame material on the other side, and the link mechanism includes a joint portion When the arm is fixed, the arm on the other side is caught by the positioning block erected on one of the first or second arm, and the positioning block has its own weight above the joint portion of the robot. Support And it is configured to. With this configuration, the joint portion can be fixed without operating the driving device when the robot is idling in an upright state.

  When the above joint part bends and stretches, the link mechanism opens and closes at an angle of π rad or less formed by the first arm and the second arm, and when the joint part is fixed, In the link mechanism, an angle formed by the first arm and the second arm is opened at an angle larger than πrad, and the other arm is hooked on the positioning block in an over-open state so that the positioning block is a robot. It is set as the structure which supports the self-weight of the structural member above the joint part.

  The positioning block is erected in the vicinity of the connecting portion between the first arm and the second arm, and the end of the arm on the other side is rounded so as not to interfere with the positioning block during rotation. When the link mechanism is kept in an over-open state, it is preferable that a side portion of the other arm is hooked on the positioning block.

  It is preferable that the joint portion described above is a knee joint, the upper frame material is a thigh frame, and the lower frame material is a lower leg frame.

  Alternatively, it is preferable that the above-described joint portion is an ankle joint, the upper frame material is a lower leg frame, and the lower frame material is a foot frame.

  According to the present invention, it is possible to provide a joint lock mechanism for a robot that can fix a joint portion without operating a driving device in an idling state where the robot is standing upright.

  Hereinafter, specific embodiments to which the present invention is applied will be described in detail with reference to the drawings. However, the present invention is not limited to the following embodiments. In addition, for clarity of explanation, the following description and drawings are simplified as appropriate.

<Embodiment 1>
A robot joint lock mechanism according to a first embodiment of the present invention will be described with reference to FIGS. This joint lock mechanism of the robot (hereinafter sometimes simply referred to as a joint lock mechanism) is preferably implemented as a mechanism that locks a joint that acts on its own weight, such as an ankle joint of a humanoid robot.

  As shown in FIG. 1, the joint lock mechanism of the present embodiment includes a thigh frame 2 that is an upper frame material and a crus frame 3 that is a lower frame material across a knee joint 1 that is a joint portion, and a thigh frame. 2 and a crus frame 3 are rotatably connected, a drive device 5 provided on the crus frame 3 and a link mechanism 6 are provided.

  The lower end portion of the thigh frame 2 and the upper end portion of the lower leg frame 3 are formed with inclined portions so as not to interfere with each other when they are bent.

  The connection mechanism 4 is a typical hinge mechanism used for a joint portion of a robot, and is arranged at the tip of each inclined portion so that the thigh frame 2 and the crus frame 3 can bend and stretch.

  The drive device 5 is a motor such as a servo. The driving device 5 is provided at the upper end of the lower leg frame 3 so that the rotation shaft protrudes laterally.

  As shown in FIG. 2, in the link mechanism 6, the end 7a of the first arm 7 made of a flat plate member and the end 8a of the second arm 8 also made of a flat plate member are rotatably connected. . The link mechanism 6 is disposed on the side of the knee joint 1, and the end 7 b of the first arm 7 is rotatably connected to the rear end of the inclined portion of the thigh frame 2. The end portion 8 b is connected to the rotation shaft of the drive device 5.

  In particular, the link mechanism 6 includes a straight line L connecting the rotation axis 9 of the first arm 7 and the second arm 8 and the point A where the first arm 7 is connected to the thigh frame 2, and the rotation axis 9 and the first axis. The angle formed between the second arm 8 and the straight line M connecting the point B connected to the rotation axis of the driving device 5, that is, the angle θ formed between the first arm 7 and the second arm 8 is 180 ° (πrad). The rotation of the second arm 8 is limited when exceeding. Specifically, the positioning block 10 is erected on the side opposite to the rotation region of the second arm 8 in the vicinity of the connection portion of the first arm 7 with the second arm 8. The link mechanism 6 is configured such that the side portion of the second arm 8 is caught by the positioning block 10 when the angle θ exceeds 180 ° and is in an over-open state. At this time, the end portion 8a of the second arm 8 is R-processed so as not to interfere with the positioning block 10 during rotation, and preferably has a shape with a reduced corner. Incidentally, the link mechanism 6 of the present embodiment is connected to the thigh frame 2 and the driving device 5 so that the positioning block 10 is disposed on the rear side of the robot.

  When the knee joint 1 is bent, the joint lock mechanism having such a configuration rotates the rotation shaft of the drive device 5 in the arrow direction R as shown in FIG. The angle θ formed by the arm 8 is smaller than 180 °, and the rotation axis 9 between the first arm 7 and the second arm 8 is connected to the connection point A between the first arm 7 and the thigh frame 2, The first arm 7 and the second arm 8 are closed so as to be arranged behind a straight line N connecting the second arm 8 and the connecting point B of the rotation shaft of the driving device 5.

  When extending the knee joint 1, as shown in FIG. 4, the rotation axis of the driving device 5 is rotated in the arrow direction S, and the angle θ formed by the first arm 7 and the second arm 8 is 180. The first arm 7 and the second arm 8 are opened so that the rotational axis 9 between the first arm 7 and the second arm 8 is arranged on a substantially straight line N slightly smaller than 0 °.

  When the knee joint 1 is fixed and the robot is in an idling state in an upright state, as shown in FIG. 1, the rotation shaft of the driving device 5 is further rotated in the arrow direction S from the state of FIG. When the second arm 8 is hooked on the positioning block 10 of the first arm 7 with the angle θ formed by the first arm 7 and the second arm 8 being larger than 180 °, the second arm 8 is hooked on the positioning block 10 of the first arm 7. The positioning block 10 can support the own weight of the component above the knee joint 1 of the robot in a state where is fixed. Therefore, it is possible to fix the knee joint 1 without operating the driving device 5 in the idling state where the robot is standing upright. Therefore, the battery for operating the drive device 5 can be reduced in size, and the drive device 5 can also be reduced in size.

  Although the drive device 5 of this embodiment is provided on the lower leg frame 3, it may be provided on the thigh frame 2. In this case, the end 7b of the first arm 7 is connected to the rotation shaft of the drive device 5, and the end 8b of the second arm 8 is rotatably connected to the crus frame 3.

<Embodiment 2>
Although the joint locking mechanism of the first embodiment is employed in the knee joint portion, it may be employed in the ankle portion as shown in FIG.

  Specifically, the lower leg frame 3 forms an upper frame material, and the foot frame 11 forms a lower frame material. A driving device 15 is provided on the crus frame 3, and an end portion 17 b of the first arm 17 of the link mechanism 16 is connected to a rotation shaft of the driving device 15. The end 18b of the second arm 18 is rotatably connected to the heel portion of the foot frame 11. The link mechanism 16 has substantially the same configuration as the link mechanism 6 of the first embodiment, but the positioning block 20 is provided on the second arm 18.

  Also in the joint lock mechanism having such a configuration, when the ankle is fixed and the robot is in an idling state in an upright state, the angle θ formed by the first arm 17 and the second arm 18 is 180. When the second arm 18 is hooked on the positioning block 20 of the first arm 17 in an over-open state larger than °, the positioning block 20 supports the weight of the component above the ankle of the robot with the ankle fixed. be able to. Therefore, the ankle can be fixed without operating the driving device 15 in the idling state in an upright position. Therefore, the battery for operating the driving device 15 can be reduced in size, and the driving device 15 can also be reduced in size.

  Incidentally, as shown in FIG. 5, it is more preferable to use the joint locking mechanism of the present invention together with the knee joint portion.

  Although the drive device 15 of the present embodiment is provided on the lower leg frame 3, it may be provided on the foot frame 11. In this case, the end 17 b of the first arm 17 is rotatably connected to the crus frame 3, and the other end 18 b of the second arm 18 is connected to the rotation shaft of the driving device 15.

  In the link mechanisms 6 and 16 of the first and second embodiments, the positioning blocks 10 and 20 are disposed on the rear side of the robot, but may be disposed on the front side. In this case, the opening and closing directions of the link mechanisms 6 and 16 are reversed.

It is the side view which showed roughly the form which employ | adopted the joint lock mechanism of the robot of this invention as a knee joint. It is the perspective view which showed the link mechanism. It is the side view which showed roughly the state which bent the knee joint. It is the side view which showed roughly the state which extended the knee joint. It is the side view which showed roughly the form which employ | adopted the joint lock mechanism of the robot of this invention for the ankle.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Knee joint 2 Thigh frame 3 Lower leg frame 4 Connection mechanism 5 Drive device 6 Link mechanism 7 First arm 8 Second arm 10 Positioning block 11 Foot frame 15 Drive device 16 Link mechanism 17 First arm 18 Second arm 20 Positioning block

Claims (5)

It is a mechanism that locks the joint part where its own weight acts such as the ankle joint of the robot,
With upper and lower frame materials across the joint,
A connection mechanism for rotatably connecting the upper frame material and the lower frame material;
A driving device such as a motor provided on one of the upper or lower frame members;
The first arm and the second arm are rotatably connected, the end of one arm is connected to the driving device, and the end of the other arm is rotatable to the frame material on the other side A linked link mechanism,
The link mechanism is in an over-open state when the joint portion is fixed, and the other arm is hooked on the positioning block standing on the first or second one arm, and the positioning block becomes the joint portion of the robot. A joint lock mechanism for a robot that supports the weight of the upper component. When the joint portion bends and stretches, the link mechanism opens and closes at an angle of π rad or less formed by the first arm and the second arm,
When the joint portion is fixed, the link mechanism opens at an angle larger than π rad between the first arm and the second arm, and in an over-open state, the link mechanism is moved to the positioning block on the other side. The robot joint locking mechanism according to claim 1, wherein the arm is hooked and the positioning block supports the weight of a component above the joint of the robot. The positioning block is erected in the vicinity of the connecting portion between the first arm and the second arm,
The end of the arm on the other side is R-processed so as not to interfere with the positioning block during rotation, and when the over-opened state of the link mechanism is maintained, the side portion of the arm on the other side The robot joint locking mechanism according to claim 1 or 2, wherein the hook is caught by the positioning block.   The robot according to claim 1, wherein the joint portion is a knee joint, the upper frame material is a thigh frame, and the lower frame material is a lower thigh frame. Joint lock mechanism.   The robot according to claim 1, wherein the joint portion is an ankle joint, the upper frame material is a lower leg frame, and the lower frame material is a foot frame. Joint lock mechanism.

Images