PARALLEL LINK MECHANISM, CONSTANT VELOCITY UNIVERSAL JOINT, AND LINK ACTUATOR

摘要

A parallel link mechanism includes a proximal end side link hub; a distal end side link hub; and three or more link mechanisms that connect the distal end side link hub to the proximal end side link hub in a position-changeable fashion. Each of the link mechanisms has a trinodal structure. Each revolute pair of each of the link mechanisms includes one pair of pair constituent members connected to each other via a bearing. One of the pair constituent members is formed with a shaft portion fitted to an inner periphery of an inner ring of the bearing, and the other of the pair constituent members is formed with an annular inner face forming portion fitted to an outer periphery of an outer ring of the bearing.

主权项

1. A parallel link mechanism comprising:
a proximal end side link hub; a distal end side link hub; and three or more link mechanisms that connect the distal end side link hub to the proximal end side link hub in a position-changeable fashion, each of the link mechanisms having a trinodal structure with four revolute pairs, and including a proximal side end link member, one end of the proximal side end link member being pivotably connected to the proximal end side link hub; a distal side end link member, one end of the distal side end link member being pivotably connected to the distal end side link hub; and an intermediate link member which is pivotably connected to the other ends of the proximal side end link member and the distal side end link member, and each of the link mechanisms having such a shape that a geometric model of the link mechanism represented by lines shows symmetry between a proximal end side portion thereof and a distal end side portion thereof with respect to a center portion of the intermediate link member, wherein each revolute pair of each of the link mechanisms includes one pair of pair constituent members connected to each other via a bearing, wherein one of the pair constituent members is formed with a shaft portion fitted to an inner periphery of an inner ring of the bearing, and the other of the pair constituent members is formed with an annular inner face forming portion fitted to an outer periphery of an outer ring of the bearing, and wherein the bearing has a critical oscillation angle smaller than a maximum value in a possible range of a bending angle which is defined as an angle between a central axis of the proximal end side link hub and a central axis of the distal end side link hub is employed.