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:
Jul. 05, 2011
Filed:
Sep. 28, 2009
Atsushi Takeyama, Yasu, JP;
Hidenori Shimizu, Hikone, JP;
Atsushi Takeyama, Yasu, JP;
Hidenori Shimizu, Hikone, JP;
Panasonic Electric Works Power Tools Co., Ltd., Shiga, JP;
Abstract
A rotary impact tool includes a drive shaft rotationally driven by a rotational drive power source, a hammer arranged around the drive shaft, a ball engaging with a cam groove formed on the outer circumferential surface of the drive shaft and a cam groove formed on the inner circumferential surface of the hammer, an anvil engageable with the hammer along a rotational direction and a spring for biasing the hammer toward the anvil. The hammer is designed to rotate along a rotational locus decided by the cam groove of the drive shaft and the cam groove of the hammer. The rotational locus of the hammer as seen in a development view describes a curve in which the lead angle of the rotational locus varies continuously with the change in hammer rotation angle.