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:
Dec. 06, 1994
Filed:
Oct. 12, 1993
Stephen A Edelen, Battle Creek, MI (US);
Robert W Jones, Canton, MI (US);
Eaton Corporation, Cleveland, OH (US);
Abstract
A parking brake system is provided which includes a dual solenoid operated valve located in series with the emergency brake control valve of a hydraulically operated brake system. The dual solenoid valve is operable to either one of two mechanical detent positions so that positioning of the valve is retained in the event of loss of power. The dual solenoid valve is controlled by the vehicle operator from the transmission console and removes fluid pressure from the brakes when actuated to a PARK position. An electronic control unit is provided for sensing the speed of the vehicle and the pressure in the hydraulic line to the brakes and provides a PARK enabling signal when the vehicle speed is below a predetermined amount. When a gear is selected at the console the dual solenoid valve is actuated to a position permitting fluid pressure to be applied to the brakes and effectively returns control of the brakes to the emergency brake control device. A pressure sensor is provided in the line to the brakes and is used to provide feedback to the driver and to control transmission shifting.