Patent · US Expired

Driving force support for linear actuator

US4727762A · kind A · utility

33Cited by
12References
1Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 2, 1986
Grant dateMar 1, 1988
Priority date
Expiry dateOct 2, 2006

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T74/19847
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

This improved driving force support is used in a linear actuator in which rotary motion of a rotating screw shaft is converted to linear motion of a travelling nut. The driving force support comprises a pair of springs surrounding the rotating shaft and held in compression between a pair of shaft bearing receivers. The receivers and bearings held thereby move axially with the rotating shaft as axial forces are applied to the shaft by the travelling nut. The bearing receivers slide axially in a hollow housing. The springs are arranged in series between seats which normally abut the respective bearing receivers and also normally abut stop surfaces in the housing. One spring has a high degree of stiffness, and the other has a comparatively low degree of stiffness. An intermediate seat between the springs has a projection which abuts the seat on the opposite end of the weaker spring to limit the flexure of the weaker spring, while allowing it to compress as the bearing receivers move axially through a short distance. When the driving force exceeds a predetermined limit, the resulting axial movement of the bearing receivers is detected by a limit switch, which can be used to stop the ac…

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