摘要 |
A ball circulation type of screw and nut spiral gearing having a ball return tube establishing a passage between the ball guiding channels of the gearing within an elongated peripheral slot formed in the nut. A spacer is disposed between the ball return tube and a cover wall surrounding the nut to maintain the spacer and ball return tube in proper assembled positions. The spacer and ball return tube are interengaged to form a preassembly unit for joint installation into the peripheral slot of nut during assembly of the gearing. |