초록 ▼

Compressed air is introduced into a cylinder chamber to displace a piston closely to a target position. Then, a ball screw shaft is rotated about its own axis by an electric motor to inch the piston to the target position. Upon arrival of the piston at the target position, the ball screw shaft is st

Compressed air is introduced into a cylinder chamber to displace a piston closely to a target position. Then, a ball screw shaft is rotated about its own axis by an electric motor to inch the piston to the target position. Upon arrival of the piston at the target position, the ball screw shaft is stopped by a brake mechanism to hold the piston accurately in the target position. The drive shaft of the electric motor extends parallel to the ball screw shaft, thus reducing the entire length of a servo cylinder apparatus. Solenoid-operated directional control valves, for supplying compressed air to the cylinder chamber and the brake mechanism are coupled integrally to a cylinder assembly, so that pipes are shortened for allowing the piston to be displaced and stopped quickly and accurately.

대표청구항 ▼

A servo cylinder apparatus comprising: a piston displaceably disposed in a cylinder chamber defined in a cylinder assembly; a piston rod having an end fixed to said piston and an opposite end exposed out of said cylinder chamber; pressure supply means comprising a solenoid-operated directional contr

A servo cylinder apparatus comprising: a piston displaceably disposed in a cylinder chamber defined in a cylinder assembly; a piston rod having an end fixed to said piston and an opposite end exposed out of said cylinder chamber; pressure supply means comprising a solenoid-operated directional control valve for supplying a fluid pressure to said cylinder chamber; a ball screw shaft engaging said piston; an electric motor coupled to said ball screw shaft; a drive shaft coupled to said electric motor and extending parallel to said ball screw shaft; first rotating means coupled to an end of said ball screw shaft and second rotating means coupled to said drive shaft, and rotation transmitting means connected between said first and second rotating means; and brake means for braking said ball screw shaft against rotation to thereby hold said piston in a predetermined position, said brake means comprising a brake mechanism for releasing said ball screw shaft in response to application of a fluid pressure thereto and braking said ball screw shaft in response to removal of a fluid pressure therefrom, said brake mechanism comprising a normally closed solenoid-operated directional control valve for connecting a fluid pressure supply to said brake mechanism to apply the fluid pressure thereto in response to an actuating signal and removing the fluid pressure from said brake mechanism in response to an inactivating signal; wherein said piston is displaced closely to a target position under said fluid pressure supplied to said cylinder chamber, thereafter said ball screw shaft is rotated by said electric motor to inch said piston toward said target position, and when said piston reaches said target position, said ball screw shaft is braked against rotation by said brake means to stop said piston in said target position.