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. 30, 1989
Filed:
Jul. 20, 1988
Sanden Corporation, Gunma, JP;
Abstract
A damper position control device for an automotive air conditioning system having a lock release mechanism for the drive shaft of a motor which controls the angular position of an air mix damper. A damper position control device is disclosed which controls the angular position of an air mix damper. The damper position control device includes a motor actuator which drives the air mix damper and a control circuit. The motor actuator includes a drive motor for the air mix damper and a rotation control device including a regulator which regulates the upper and lower rotational limits of the shaft of the drive motor and a position detector which detects the rotational angle of the shaft. The control circuit controls the motor actuator in accordance with a plurality of detected signals. The control circuit generates a drive signal which drives the motor actuator and further includes a lock detector which detects if the shaft of the motor is locked against rotational motion in a first rotational direction. The control circuit also includes a lock release which releases the motor so as to permit rotational motion in a second rotational direction after the motor as been locked against rotational motion in the first rotational direction if the motor is within a first predetermined angular displacement from the upper rotational limit or within a second predetermined angular displacement from a lower rotational limit and if the drive signal causes the motor to rotate in the second rotational direction.