Abstract: A pressurized fluid actuated shift bar housing assembly (12) for a change gear transmission (10) is provided having a plurality of shift bars (54, 56, 58), each shift bar having associated therewith a first (108) and a second (110) selectively pressurized and exhausted chamber utilized to axially position the shift bar in a first and second axially displaced position. A third relatively small volume selectively pressurized chamber (140) is utilized to positively axially position each of the shift bars in the nondisplaced axially centered positions thereof.

Abstract: An improved spindle control mechanism for a lathe that includes, in preferred form, a rotatable control knob operably related to a plurality of spindle motor control and servo-control switches by a switch drum fixed thereto and operably connected to a spindle transmission through a control shaft by a connector link pivoted in an eccentric position at one end to the control knob and pivoted at the other end to a lever arm fixed to the control shaft. Rotation of the control knob into a forward position simultaneously translates the lathe's transmission into a forward spindle rotation position and starts the spindle drive motor. Rotation of the control knob into an intermediate stop position simultaneously stops the spindle drive motor and activates the spindle servo-control switch (which permits the spindle's rotation speed to be changed by a separate spindle servo-control mechanism, if desired).