| 摘要 |
<p>A dual drive ball screw (40) has a ball screw shaft (42) coupled at one end to a gear train and coupled at the other end to a ball screw nut (60). The ball screw shaft and ball screw nut are connected through complementary helical grooves filled with ball bearing balls (64). The outer surface of the ball screw nut is splined and can be driven by a second gear train. An output tube (70) is coupled at one end to the ball screw nut and at its opposite end has a connector portion with a groove on its inner surface. A rod end (80) has a coupling member (82) for coupling to a surface to be actuated and a shaft portion (84) with a groove (88) on its outer surface. This shaft portion is received within the output tube portion and the corresponding grooves (74) are coupled through the use of a plurality of ball bearing balls (90). This arrangement for coupling the rod end to the connector portion, referred to as a rod end swivel, improves the performance, i.e. lower weight and smaller envelope of the ball screw over the prior art ball screws that use thrust and needle bearings.</p> |
