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:
Jan. 02, 2007
Filed:
Oct. 13, 2004
Kozo Kawai, Neyagawa, JP;
Yoshinori Sainomoto, Sanda, JP;
Tatsuhiko Matsumoto, Habikino, JP;
Tadashi Arimura, Kyoto, JP;
Toshiharu Ohashi, Sakata-gun, JP;
Hiroshi Miyazaki, Hikone, JP;
Hidenori Shimizu, Hikone, JP;
Fumiaki Sawano, Hikone, JP;
Kozo Kawai, Neyagawa, JP;
Yoshinori Sainomoto, Sanda, JP;
Tatsuhiko Matsumoto, Habikino, JP;
Tadashi Arimura, Kyoto, JP;
Toshiharu Ohashi, Sakata-gun, JP;
Hiroshi Miyazaki, Hikone, JP;
Hidenori Shimizu, Hikone, JP;
Fumiaki Sawano, Hikone, JP;
Matsushita Electric Works, Ltd., Osaka, JP;
Abstract
In a power fastening tool for fastening a fastening member such as a screw or a fastening member, malfunction that driving of a motor is stopped before the fastening member is fastened completely can be prevented. A fastening judger judges that the fastening operation is completed when a value of an estimated torque T for fastening the fastening member becomes larger than a predetermined lower limit value Tpreviously set by a user and a value of a torque variation ratio ΔΔT varies from positive to negative. Thus, it is possible to prevent malfunction for stopping driving of a motor even when the value of the torque variation ratio ΔΔT varies from positive to negative due to trouble before the vale of the estimated torque T becomes larger than the lower limit value T