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:
May. 05, 2015
Filed:
Sep. 26, 2011
Pingbo Shi, Nanjing, CN;
Dezhong Yang, Nanjing, CN;
Pingbo Shi, Nanjing, CN;
Dezhong Yang, Nanjing, CN;
Chervon (HK) Limited, Hong Kong, HK;
Abstract
An over-temperature protection circuit for a direct current (DC) electric tool includes a current detecting circuit electrically coupled to a battery pack, a power device control circuit electrically coupled to an electric motor of the DC electric tool and a power device for controlling the power state of the circuit. A computation control circuit controls the power supply of the motor according to the circuit current value detected by the current detecting circuit. When the electric motor is not in a speed control state, the allowable current passing through the over-temperature protection circuit of the DC electric tool cannot exceed a preset first current value. When the electric motor is in the speed control state, the allowable current passing through the over-temperature protection circuit of the DC electric tool cannot exceed a preset second current value less than the first current value.