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. 28, 1998
Filed:
Nov. 26, 1996
Tomoyuki Ogawa, Gunma-ken, JP;
Iwao Tsurubuchi, Gunma-ken, JP;
Mitsuba Corporation, Kiryu, JP;
Abstract
In a control circuit for a vehicle windshield wiper system, a relay energization retaining circuit forms a self-sustaining circuit jointly with a relay drive transistor for driving a wiper relay, and maintains supply of electric current to the wiper motor when the ON signal for the relay drive transistor is terminated as long as the auto stop switch is at the brake position until the auto stop switch subsequently moves on to the drive position. Therefore, when the signal which normally turns on the relay drive transistor is terminated during the time the auto stop switch is at the brake position, because the relay energization retaining circuit keeps the wiper motor running until the auto stop switch changes over from the brake position to the drive position, and the auto stop switch then takes over the task of keeping the wiper motor running until the auto stop switch changes over from the drive position to the brake position, the termination of electric current to the wiper motor always occurs at the time when the auto stop switch changes over from the drive position to the brake position so that the distance or the angular range of the overrunning of the wiper motor is fixed without regard to the timing of terminating the ON signal. Thus, according to the present invention, the rest position of the wiper blade is fixed under all operating conditions.