Drain System for a Linear Actuator
Original Publication Date: 1984-Jul-01
Included in the Prior Art Database: 2005-Feb-04
This apparatus provides reduction of external oil leakage from an open-frame linear actuator. Many hydraulic actuators have a case enclosing the final drive components. This case allows hydraulic fluid leaking past the high pressure seals to drain back to the hydraulic reservoir. The linear actuator 10, shown in Fig. 1 operating a robot arm, has an open frame that exposes the final drive components. The linear actuator 10 design is such that it is very difficult to seal the case to allow hydraulic fluid to drain back to the reservoir. The high speeds required in robotic applications dictate extensive up and down motions of the pistons 12 which make bellows or other ways of enclosing the case not practical because of wear. Sealing the case would require extensive sliding seal surfaces joined at right angles.