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:
Oct. 07, 1997
Filed:
Jun. 01, 1995
Applicant:
Inventors:
Yasuo Sasaki, Hitachinaka, JP;
Mitsuo Ogura, Hitachinaka, JP;
Assignee:
Hitachi Koki Company Limited, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B25B / ;
U.S. Cl.
CPC ...
173178 ; 173 936 ; 173 97 ;
Abstract
An improved structure of an impact screwdriver is provided which achieves a low-noise screw-driving operation. The impact screwdriver includes a clutch assembly for transmitting torque provided by a motor to a tool bit. The clutch assembly includes a toque-transmitting member, a torque-outputting member, and a clutch coil spring. The clutch coil spring is selectively wound around the torque-transmitting member and the torque-outputting member according to a rotational difference therebetween to establish torque transmission for providing the torque to the tool bit intermittently.