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. 09, 2001
Filed:
Sep. 28, 1998
Chikai Yoshimizu, Hitachinaka, JP;
Hiroaki Orikasa, Hitachinaka, JP;
Takahiko Shimada, Hitachinaka, JP;
Shigeru Shinohara, Hitachinaka, JP;
Eiji Nakayama, Hitachinaka, JP;
Kazuhiko Funabashi, Hitachinaka, JP;
Atsushi Nakagawa, Hitachinaka, JP;
Hitachi Koki Co., LTD, Tokyo, JP;
Abstract
A DC power source unit includes a main unit that generates DC voltage, and an output cable. The output cable has one end connected to the output of the main unit and another end attached to an adapter plug. The adapter plug Is electrically connected to an electrically powered tool, such as an electrical drill. Current flowing in the tool is detected every predetermined interval and accumulated electrical quantity is computed based on the detected current flowing in the tool. Based on the accumulated electrical quantity, the temperature of the tool is predicted. When it is determined that the tool is heated up to a first critical temperature based on the accumulated electrical quantity, an alarm unit is actuated. When it is determined that the tool is further heated up to a second critical temperature, supply of current to the tool is interrupted.