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:
Sep. 25, 1979
Filed:
Sep. 29, 1976
Robert F Deike, Cheyenne, WY (US);
Foresight Industries, Cheyenne, WY (US);
Abstract
A driver tool of the power hammer type is equipped with a compression spring acting on the anvil of the tool and loaded by the weight of the tool and by downcrowding to store energy from the load and from attempted rebound of the anvil which is released to the anvil in a driving direction adding to the driving force of the hammer. The spring has a stiffness and a length effective to maintain a free stroke length for the hammer before impacting the anvil when the tool is loaded or downcrowded sufficiently to maintain the anvil thrusting against the workpiece and to develop and build up vibrations from the hammer blows. The hammer blows are divided into impulses by the vibrations allowing the workpiece to recover from blows of magnitudes beyond the elastic limit of the workpiece material which would otherwise damage the workpiece. The preferred spring is a cylindrical spaced coil helical spring having its bottom coil engaging the anvil in good vibration transferring relation and a top end coil bottomed on the end wall of a slip housing surrounding the spring and anvil. The housing is bottomed on the bottom end face of the tool body. A nonmetallic slip washer is preferably interposed between the housing and the bottom end of the tool body to dampen transfer of vibrations into the tool body and to accommodate rotation of the anvil which is desirable when rock drill and the like breaker tools are mounted on the anvil.