| 摘要 |
A distal end side link hub (3) is connected to a proximal end side link hub (2) via three or more link mechanisms (4) such that alteration in posture of the distal end side link hub is allowed. Each of the link mechanisms (4) includes a proximal side end link member (5), a distal side end link member (6), and an intermediate link member (7). A line member (33) is disposed between the link hubs (2, 3), two ends of the line member (33) being held at line member holding points (Q1, Q2) which are on link hub central axes (B, C), respectively. In a state where the link hubs (2, 3) are parallel to each other, when the distance from a midpoint (O) to each spherical link center (P1, P2) is defined as (D) and the distance from each spherical link center (P1, P2) to its corresponding line member holding point (Q1, Q2) is defined as (H), the relationship H = 0.5 × D is established. |
