Reversible mechanical arm gravitational torque balancing device

Patent metadata

Field	Value
Publication number	US-10682772-B2
Application number	US-201816011314-A
Country	US
Kind code	B2
Filing date	Jun 18, 2018
Priority date	Apr 20, 2018
Publication date	Jun 16, 2020
Grant date	Jun 16, 2020

Abstract

The present invention belongs to the field of medical rehabilitation training equipment, and particularly discloses a reversible mechanical arm gravitational torque balancing device, comprising a counterweight guide groove module, a counterweight, a mechanical arm joint, a rope, a guide pulley block, a counterweight disc, a mechanical arm joint link and a rack. The counterweight guide groove module is mounted on the rack; the counterweight has a lower end mounted on the counterweight guide groove module and an upper end connected to the rope, and the rope is wound on the counterweight disc after passing through the guide pulley block mounted on the rack; the mechanical arm joint is mounted on the rack and internally provided with a motor; the counterweight disc is mounted on an output shaft of the motor of the mechanical arm joint; and the mechanical arm joint link is also mounted on the output shaft of the motor of the mechanical arm joint and the gravity of the mechanical arm joint link produces a gravitational torque on the mechanical arm joint. The present invention can change the direction of the provided balance torque when the mechanical arm performs the morphological transformation, and features simple, rapid and labor-saving operation as well as reliable structure.

First claim

The present invention claimed is:

1. A reversible mechanical arm gravitational torque balancing device, comprising a counterweight guide groove module, a counterweight, a mechanical arm joint, a rope, a guide pulley block, a counterweight disc, a mechanical arm joint link and a rack, wherein the counterweight guide groove module is mounted on the rack to limit the movement of the counterweight, thereby achieving the clamping function; the counterweight has a lower end mounted on the counterweight guide groove module and an upper end connected to the rope, and the rope is wound on the counterweight disc after passing through the guide pulley block mounted on the rack; the mechanical arm joint is mounted on the rack and internally provided with a motor; the counterweight disc is mounted on an output shaft of the motor of the mechanical arm joint and the mechanical arm joint limits the rotational degree of freedom of the counterweight disc around the output shaft of the motor; and the mechanical arm joint link is also mounted on the output shaft of the motor of the mechanical arm joint and the gravity of the mechanical arm joint link produces a gravitational torque on the mechanical arm joint.

2. The reversible mechanical arm gravitational torque balancing device of claim 1 , wherein the counterweight guide groove module includes a counterweight mounting block, a reversing guide groove portion, a clamping device, a guide shaft and a module base plate, in which the counterweight is mounted on an upper end of the counterweight mounting block; an upper end of the reversing guide groove portion is mounted on the lower end of the counterweight mounting block, a guide hole matched with the guide shaft is formed in the middle part of the reversing guide groove portion, and a guide groove having a preset shape is formed on the side of the reversing guide groove portion; the clamping device is mounted on the module base plate; a lower end of the guide shaft is mounted on the module base plate; and the reversing guide groove portion is movable up and down along the guide shaft and during the up-and-down movement of the reversing guide groove portion, the guide groove having a preset shape on the side of the reversing guide groove portion cooperates with the clamping device to limit the movement of the reversing guide groove portion in a predetermined position, thereby achieving the clamping function.

3. The reversible mechanical arm gravitational torque balancing device of claim 1 , wherein the clamping device includes a clamping pin, a clamping pin mounting bracket, a linear guide, a spring and a spring mounting bracket, in which the clamping pin is mounted on an upper end of the clamping pin mounting bracket; a lower end of the clamping pin mounting bracket is mounted on the upper end of the linear guide; the lower end of the linear guide is mounted on the module base plate; the spring has one end connected to the clamping pin mounting bracket and the other end connected to the spring mounting bracket; and the spring mounting bracket is mounted on the module base plate.

4. The reversible mechanical arm gravitational torque balancing device of claim 3 , wherein the clamping pin and the clamping pin mounting bracket as a whole are mounted on the linear guide and movable along the linear guide; and the spring exerts a pulling force on the clamping pin mounting bracket so that the clamping pin and the clamping pin mounting bracket as a whole have a tendency to move toward the spring.

5. The reversible mechanical arm gravitational torque balancing device of claim 1 , wherein the gravity of the counterweight and the counterweight mounting block and the reversing guide groove portion of the counterweight guide groove module is converted into a pulling force on the rope, and the pulling force is converted into, on the counterweight disc, a balance torque which is opposite in direction to the gravitational torque and plays a role in balancing the gravitational torque.

6. The reversible mechanical arm gravitational torque balancing device of claim 1 , wherein when the direction of the balance torque needs to be changed, the counterweight disk is driven by the motor of the mechanical arm joint to rotate in the opposite direction of the initial balance torque, so that the counterweight ascends and then stops ascending under the limitation of the guide groove having a preset shape on the side of the reversing guide groove portion; the motor of the mechanical arm joint is stopped, so that the counterweight descends under the action of gravity and then stops descending under the limitation of the guide groove during the descending process; the limitation of the counterweight disc by the mechanical arm joint is released; the counterweight disc is rotated in the direction of the initial balance torque to allow the rope to be reversely wound on the counterweight disc, and then the limitation of the counterweight disc by the mechanical arm joint is restored; the counterweight disk is driven by the motor of the mechanical arm joint to rotate in the direction of the initial balance torque, so that the counterweight ascends and then stops ascending under the limitation of the guide groove; and the motor of the mechanical arm joint is stopped, so that at this time, a balance torque, which is converted from the pulling force on the rope, on the counterweight disk is opposite in direction and equal in size to the initial balance torque, thereby achieve the reversing of the balance torque.

Assignees

• Univ Huazhong Science Tech

Inventors

• Xiong Caihua
• Wang Chenbo
• Wu Xuan
• Tao Jianbo
• He Chang
• Mao Wei

Classifications

• B25J19/0016 Primary

  using springs · CPC title

• A61H1/00 Primary

  Apparatus for passive exercising (A61H5/00 takes precedence); Vibrating apparatus; Chiropractic devices, e.g. body impacting devices, external devices for briefly extending or aligning unbroken bones · CPC title

• B25J19/002 Primary

  using counterweights · CPC title

• B25J18/04

  rotatable · CPC title

• A61H1/02

  Stretching or bending {or torsioning} apparatus for exercising · CPC title