| 摘要 |
<p>A differential drive mechanism comprises a cage (8), which is rotatable about an axis (6) and represents the input, two coaxial output shafts (2, 4) which are rotatable with respect to the cage (8) about the said axis, a coupling (16) which is connected eccentrically to the two output shafts (2, 4) to transmit relative contrarotational movement between them by connections (12, 22, 24) which permit relative rotation of the coupling (16) and the output shafts about an axis substantially parallel to the said axis and a restraint member (20) which is coupled to the cage (8) and to the coupling (16) such that the coupling (16) is rotatable with respect to the cage (8) about an axis substantially perpendicular to the said axis and is capable of reciprocating movement in a direction perpendicular to the said axis but prevented from movement in a direction parallel to the said axis (6). The eccentric connection of the coupling (16) and the output shafts (2, 4) includes a respective eccentric hole (12) formed in the inner end (10) of each output shaft (2, 4) in which the associated end of the coupling (16) is received, the ends of the coupling (16) having a part-spherical engagement surface. One or more portions of the coupling (16) or of a member connected to it (18; 2, 4; 20) constitute a piston which is slidably received in the respective cylinder defined by a further component or components (8, 20; 8) of the differential drive mechanism. The said portion(s) of the coupling (16) or of the said member (18; 2, 4; 20) or one of the said further components (8, 20; 8) defines a restricted passage (36; 42; 44; 58) which connects the cylinder to a further space. When differential rotation of the output shafts (2, 4) occurs a fluid, such as oil, within the cylinder is cyclically discharged into and withdrawn from the further space through the restricted passage.</p> |
