The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 31, 1989
Filed:
Nov. 20, 1986
Teddy L Jones, Cherry Valley, IL (US);
Sundstrand Corporation, Rockford, IL (US);
Abstract
A non-jamming electro-mechanical hydrostatic actuator system includes one embodiment in which a ballscrew assembly has a rotatable nut and an axially movable ballscrew. A motor rotates the nut to axially move the ballscrew. An actuator is operatively connected to a load to be actuated. A hydraulic system is coupled between the ballscrew and the actuator and includes a closed hydraulic circuit for statically trapping fluid in the circuit to effect movement of the actuator in response to movement of the ballscrew. The closed circuit is selectively opened to allow fluid flow in the circuit in the event of failure or jamming of the ballscrew assembly to allow reaction movement of the actuator in response to load forces. In another embodiment a rotary vaned assembly includes a cylinder housing a rotary vane, with the motor rotating the cylinder. The hydraulic system is coupled between the cylinder and the vane and includes a closed hydraulic circuit for statically trapping fluid in the circuit on opposite sides of the vane to effect conjoint rotation of the cylinder and the van. When the closed circuit is opened to allow fluid flow in the circuit the vane can rotate independently of the cylinder to allow reaction movement of the actuator in response to load forces.