JP2017110815A5 - - Google Patents

Description

In the parallel link mechanism of the present invention, the link hub on the distal end side is connected to the link hub on the proximal end side so that the posture can be changed via three or more sets of link mechanisms. The end link member on the proximal end side and the distal end side that is rotatably connected to the link hub on the side and the distal end side link hub, and both ends on the other end of the end link member on the proximal end side and the distal end side It consists of a central link member that is rotatably connected to each other. Each of the link mechanisms has a geometric model in which the link mechanism is expressed by a straight line in which the proximal end portion and the distal end portion are symmetrical with respect to the central portion of the central link member. The parallel link mechanism according to the present invention is the above-described configuration, wherein the base end side link hub and one end of the base end side end link member have a rotational pair, the front end side link hub and the front end side end link. A bearing is interposed in each of the rotational pair of the end of the member and the rotational pair of the other end of the end link member on the base end side and the end side of the member and both ends of the center link member. In this case, a smaller one than a maximum value within a possible range of a bending angle that is an angle formed by a central axis of the link hub on the base end side and a central axis of the link hub on the distal end side is used .
It is interposed in the rotational pair of the base end side link hub and one end of the base end side end link member, and the rotational pair of the front end side link hub and one end of the front end side end link member. The bearing may be provided embedded in the proximal end side link hub and the distal end side link hub . The above critical swing angle is the minimum practical swing angle of the bearing, and is the minimum swing angle that can be determined by the bearing specifications and the like to obtain the rated life.

Claims (8)

The link hub on the distal end side is connected to the link hub on the proximal end side through three or more sets of link mechanisms in such a manner that the posture can be changed, and each of the link mechanisms includes a link hub on the proximal end side and a link hub on the distal end side. End link members on the base end side and the front end side, one end of which is rotatably connected to the link hub,
A central link member whose both ends are rotatably connected to the other ends of the end side link members on the base end side and the front end side, and each of the link mechanisms has a geometric model expressing the link mechanism as a straight line. In the parallel link mechanism in which the base end side portion and the tip end side portion with respect to the central portion of the central link member are symmetrical.
Rotating pair between the base-side link hub and one end of the base-side end link member, Rotating pair between the tip-side link hub and one end of the tip-side end link member, the base-side In addition, a bearing is interposed in each rotation pair of the other end of the end link member on the distal end side and both ends of the central link member, and these bearings have a critical swing angle as a central axis of the link hub on the proximal end side. using smaller than the maximum value within the possible range of angles at which bending angle formed between the central axis of the distal end side link hub
A parallel link mechanism characterized by that. 2. The rotation pair of the base end side link hub and one end of the base end side end link member, and the rotation of the front end side link hub and one end of the front end side end link member according to claim 1. A parallel link mechanism characterized in that the bearing interposed between a pair is embedded in the base end side link hub and the distal end side link hub. 3. The parallel link mechanism according to claim 1, wherein the critical swing angle is smaller than a maximum value of the bending angle in a predetermined work operation. The bearing according to any one of claims 1 to 3 , wherein the bearing is a deep groove ball bearing, and when the number of rolling elements of the deep groove ball bearing is Z, the critical swing angle is 2 · 180 / (0 .555 · Z · π) [deg]. The bearing according to any one of claims 1 to 3 , wherein the bearing is a cylindrical roller bearing, and when the number of rolling elements of the cylindrical roller bearing is Z, the critical oscillation angle is 2 · 180 / (0 .37 · (Z + 0.1) · π) [deg]. 4. The bearing according to claim 1 , wherein the bearing is a needle roller bearing. When the number of rolling elements of the needle roller bearing is Z, the critical swing angle is 2 · 180 /. A parallel link mechanism of (0.544 · Z · π) [deg]. A parallel link mechanism according to any one of claims 1 to 6 , comprising an input shaft on the proximal link hub of the parallel link mechanism, and an output shaft on the distal link hub. A constant velocity universal joint characterized by being provided. The parallel link mechanism according to any one of claims 1 to 6 , comprising the parallel link mechanism according to any one of claims 1 to 6 , wherein at least two sets of three or more sets of link mechanisms of the parallel link mechanism include the end link member on the base end side. A link actuating device comprising an actuator that is rotated to change a posture of the distal end side link hub with respect to the proximal end side link hub.