| 摘要 |
PURPOSE:To eliminate backlash of a ball screw pressurizing device which is composed of two ball screws fitted to a screw shaft through many balls, by using a spring between both nuts for energizing them in the turning direction. CONSTITUTION:A screw shaft 1 is screwed in two nuts 3, 4 through many balls 2. The nut 3 has a flange 31 with a diameter larger than that of the screw and the outer circumference of the other nut 4 is fitted in the inner circumference 32 of the flange 31. A thrust ball bearing 8 is put between both nuts 3, 4 and the nut 3 is fastened to other member not shown in the figure by means of a bolt through a stepped bolt hole 34. A communicating hole 5 deep through the outer circumference of the nut 4 is made on the flange 31, being formed on an axis A-A inclined at an angle alpha to a radial virtual line B-B passing the center of the screw shaft. A coil spring 6 is compressed by an adjusting screw 7 to pressurize both nuts 3, 4. |
