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:
Aug. 04, 1992
Filed:
Dec. 07, 1989
Akira Uno, Hitachiohta, JP;
Isamu Tanji, Katsuta, JP;
Kaoru Ichikawa, Katsuta, JP;
Sueji Tachihara, Hitachiohta, JP;
Hitachi Koki Company, Limited, Tokyo, JP;
Abstract
A pneumatic fastener driving tool includes a main valve operable to cause compressed air to be alternately introduced into and discharged from the upper piston chamber, a first passage leading the compressed air into the main valve chamber, a repeat valve disposed in the first passage for opening and closing the same, and a second passage extending between the lower piston chamber and a repeat valve chamber in which the repeat valve is reciprocably received. With this construction, the repeat valve is reciprocally movable in response to a change of pressure in the lower piston chamber to cause the main valve to reciprocate, thereby reciprocating the piston repeatedly. Since the reciprocating fastener driving movement of the piston is directly related to the reciprocating movement of the repeat valve, the fastener driving work can be achieved reliably without causing any operational failure such as a non-load striking.