To provide a direct acting device having high durability suppressing occurrence of dent and peeling on a ball surface.
The direct acting device comprises a direct acting body that engages with the outside of a shaft and straightly moves along the shaft, a plurality of rolling elements that are held in a rolling element groove formed in the inner surface side of the direct acting body and roll between the rolling element groove and the shaft, and a separator disposed between the rolling elements, and a circulation route that is formed in the direct acting body and circulates the rolling elements from one end side to the other end side of the rolling element groove. The direct acting device is filled with grease containing base oil where mulling consistency defined by JIS K2220 is in the range of 220 to 395 and kinematic viscosity at 40°C is in the range of 50 to 500 mm2/s.
| JP2006112520 | ELECTRIC LINEAR DRIVE ACTUATOR |
| JP4665365 | Ball screw device |
YAMAZAKI MASAHIKO
MIYAJIMA HIROTOSHI
