| 摘要 |
<p>An industrial robot has a lower arm (13) which is provided so that it can be turned around a first horizontal axis (C1) extending horizontally with respect to a robot body (12). A front arm (14) is provided on the lower arm so that the front arm can be turned around a second horizontal axis (C2). The front arm is turned by a driving unit, such as a motor (16). The robot body is provided with a pivotable disc (17) so that the disc can be turned around the first axis in accordance with the pivotal movement of the front arm around the second axis. A first wheel (18), the diameter of which is smaller than that of the pivotable disc, is fixed concentrically thereto. A second wheel (21), the diameter of which is substantially equal to that of the first wheel, is connected pivotably to one end of a tension spring unit (19) the other end of which is joined to the robot body. A wire (22), one end of which is connected to the pivotable disc, and the other end portion of which is engaged with the outer circumference of the first wheel and retained by the first wheel, is engaged with the outer circumference of the second wheel with the tension spring unit pulled by the wire. The wire is arranged at its one end on the pivotable disc so that, when the distal end of the front arm is directed perpendicularly downward, the portion (22b) of the wire which extends between the pivotable plate and second wheel becomes substantially parallel to the portion (22c) thereof which extends between the first and second wheels.</p> |
