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. 04, 1991
Filed:
Apr. 06, 1989
Umberto Monacelli, Monza (Milan), IT;
Other;
Abstract
A fastener driving device of pneumatic type comprises a piston (20) within a cylinder (49), and a driver (21), connected to the piston (20) and movable through a fastener driving throat (26) formed by the housing of the device. A chamber (52) is provided within the housing to function as an air pressure reservoir. First and second valves (15) provide an appreciably lower pressurized air to the underside of the piston (20). The valves (15) are so arranged that when they are in a first position they allow a flow of pressurized air from the reservoir (18) to the underside of the piston (20) and after the pressurized air under the piston (20) increases to a reduced predetermined ratio to that in the reservoir (18), the valves (15) shift to a second position blocking the flow. The valves (15) are capable of shifting to a third position allowing communication of the air pressure under the piston (20) with atmosphere while continuing to block communication with the reservoir.