The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 21, 1989
Filed:
Jan. 21, 1988
Gunnar C Hansson, Stockholm, SE;
Atlas Copco Aktiebolag, Nacka, SE;
Abstract
A power tool for two step tightening of screw joints comprising a housing (10; 50), a rotation motor supported in said housing (10; 50), an output spindle (13, 54) rotated by said motor and connectable to a screw joint to be tightened, a power transmission including a clutch means (16-18, 25; 58, 60, 67) incorporated between said motor and said output spindle (13; 54), and power supply means connecting said motor to a power source. The clutch means (16-18, 25; 58, 60, 67) comprises a shift means (31; 84, 85) by which the mode of operation of the clutch means (16-18, 25; 58, 60, 67) is shiftable between a torque responsive releasing action during the first, high speed step of the tightening process and a non-releasing action during the second, low speed step of the tightening process, and a release detecting means (23; 83) associated with said clutch means (16-18, 25; 58, 60, 67) and arranged to act upon said power supply means to cause at least a substantial reduction in the power supply to the motor as said clutch means (16-18, 25; 58, 60, 67) is released during the first, high speed step of the tightening process.