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:
Jun. 21, 1983
Filed:
Apr. 21, 1981
Per A Gidlund, Taby, SE;
Atlas Copco Aktiebolag, Nacka, SE;
Abstract
A vibrationless pneumatic impact tool comprises: a housing; a cylinder axially displaceable in the housing; a hammer piston reciprocably driven by pressure air in the cylinder; a recoil cushioning air volume disposed between the housing and the cylinder; a first valve arrangement located in a fixed disposition relative to the housing; and a second valve arrangement located in a fixed disposition relative to the cylinder and arranged to cooperate with the first valve. The first valve comprises at least one air inlet opening communicating with a pressure air source and at least one air venting port communicating with the atmosphere. The second valve is arranged to selectively prevent communication between the at least one inlet opening and the recoil cushioning air volume while establishing communication between the at least one venting port and the recoil cushioning air volume when the cylinder is in its extreme forward position relative to the housing, and to selectively establish communication between the at least one inlet opening and the recoil cushioning air volume while preventing communication between the at least one venting port and the air volume when the cylinder is in its extreme rear position relative to the housing. This arrangement improves handling of the impact tool.