PURPOSE: To reduce a cost though a ball screw is constituted in such a manner that dusting is suppressed.
CONSTITUTION: In a ball screw A comprising a screw a shaft 1 having a lubrication film adhered to spiral grooves 11 and 21; a nut 2; and a plurality of balls 3, the ball 3 forms a sintered substance wherein silicon nitride powder with a average grain size of 0.2-1μm to which 5-20wt.% sintering assistant, such as Y2O3 and Al2O3, is added is sintered under a pressure of 1-10 atmospheric pressure. This constitution reduces a manufacturing cost compared with conventional high grade ceramics and besides may reduce density and strength to a slightly low value. Besides, since pore opened to the surface of a sintered substance is present, wear powder of the lubrication film is trapped by the pore and stored.
| JPS6313956 | SCREW-DRIVEN FEEDER |
| JP5142536 | Actuator |
| JP2014043879 | BALL SCREW |
HAYASHIDA KAZUNORI
KITAMURA KAZUHISA
KIDA TAKEHISA
