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. 07, 2009
Filed:
Mar. 10, 2005
Yutaka Matsunaga, Anjo, JP;
Yutaka Matsunaga, Anjo, JP;
Makita Corporation, Anjo-shi, Aichi, JP;
Abstract
A fastening tool with a clutch for shutting off transmission of torque, capable of self-diagnosing fastening torque of a screw or the like at low cost without using expensive elements such as a torque sensor, etc. A fastening tool () has a motor (), a main shaft () engaging with a screw or the like, and a clutch () interposed between the motor () and the main shaft (). The clutch () transmits torque from the motor () to the main shaft () when a load acting on the main shaft () is less than a predetermined value, and shuts off torque transmission from the motor () to the main shaft () when a load acting on the main shaft () is equal to or greater than the predetermined value. The fastening tool () further has a control unit () for controlling the motor (). The control unit () monitors a current flowing to the motor () and determines whether fastening torque is normal or not based on a motor current when transmission of torque from the motor () to the main shaft () is shut off.