Patent · US Expired

Pneumatically operated screw driver

US5231902A · kind A · utility

20Cited by
5References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 3, 1992
Grant dateAug 3, 1993
Priority date
Expiry dateJun 3, 2012

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB25B23/045
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

A pneumatically operated screw driver having a pneumatically operated rotor rotatably supported in an outer frame. The rotor is only rotatable about its axis. A moving unit is slidably disposed within the rotor. The moving unit has an upper piston and is axially movable upon application of pneumatic pressure to the upper piston. The moving unit is also rotatable about its axis because of spline connection with the rotor. A valve is disposed for selectively applying the pneumatic pressure to the piston and to the rotor. Upon application of the pneumatic pressure, the moving unit is moved downwardly, and the pneumatic pressure is then introduced into the rotor for rotating the same. The rotation of the rotor is transmitted to the moving unit. The valve closes a fluid passage directing to the piston and to the rotor when the moving unit has the lowermost position.

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