Patent · US Expired

Electric impact tool

US4204622A · kind A · utility

84Cited by
3References
16Claims
0Family size

Inventors

Key dates

Filing dateApr 8, 1977
Grant dateMay 27, 1980
Priority date
Expiry dateApr 8, 1997

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T29/49833
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

This invention relates to an electric impact tool characterized by a pair of electric motor-driven counterrotating flywheels, at least one of which is movable relative to the other from a retracted inoperative position into an extended operative one closely adjacent the other flywheel whereby a ram is squeezed therebetween and impelled forward at high speed against a workpiece. The nosepiece of the tool frame is retractable although normally extended due to the spring bias urging it and the movable flywheel to which it is mechanically linked into disengaged position. These elements cooperate with one another and with a manually-actuated trigger such that the latter must be depressed and the nosepiece retracted in order to engage the high energy friction clutch defined by the flywheels so as to operate the ram. A flywheel speed control is provided for matching the ram impact to the workload. The nosepiece also includes an energy absorbing cushion effective to dissipate the excess energy carried by the ram at the end of its work stroke so as to prevent damage to the structure against which the nosepiece is pressed.

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