Patent · US Expired

Linear helical actuator

US4748866A · kind A · utility

10Cited by
37References
37Claims
0Family size

Inventor

Key dates

Filing dateSep 3, 1986
Grant dateJun 7, 1988
Priority date
Expiry dateSep 3, 2006

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T74/19953
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A fluid-powered linear actuator having a body, and an output shaft with a piston portion disposed within the body. The shaft is axially movable in a first direction in response to fluid pressure on the shaft piston portion. A piston sleeve is mounted within the body and has a piston head to define with the shaft piston portion a fluid-tight chamber. A second fluid-tight chamber is provided on the opposite side of the piston head. Exterior sleeve splines transmit torque between the sleeve and the body in response to axial movement of the piston sleeve, and interior sleeve splines transmit axial force between the sleeve and the shaft in response to axial and rotational movement of the piston sleeve. In a preferred embodiment, the sleeve splines, and hence the corresponding splines on the body and shaft have the same hand with the lead of the interior splines being greater than the lead of the exterior splines so that the application of fluid pressure to the first chamber produces axial movement of the piston sleeve and the shaft in opposite directions, with the shaft moving in a first axial direction. The fluid pressure to the first chamber also applying pressure directly on the shaf…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.