Patent · US Expired

Impulse wrench with wrap spring clutch assembly

US5941360A · kind A · utility

8Cited by
28References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 21, 1996
Grant dateAug 24, 1999
Priority date
Expiry dateNov 21, 2016

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB25B21/02
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

A rotary impulse tool has a motor-driven drive shaft and an output shaft. The drive shaft is threadedly coupled to a flywheel sleeve, which is spring-biased forwardly and is splined to a rotatable race structure of a wrap spring clutch assembly, which includes a wrap spring disposed in clearance fit coaxially between cylindrical surfaces of the race structure, the wrap spring having a front end fixed to the output shaft and a rear end coupled to a first conical control member. A second conical control member is axially movable between engaged and disengaged positions relative to the first control member for, respectively, shifting the clutch assembly to an engaged condition for transmitting torque between the drive and output shafts and a disengaged condition for decoupling those shafts. When the clutch assembly is engaged, the drive shaft rotates the output shaft and, as torque builds up on the output shaft, it slows to develop a speed differential between the drive and output shafts, which retracts the flywheel sleeve rearwardly against a compression spring to engage the second control member and move it axially to its disengaged position for disengaging the clutch assembly, wher…

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