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:
Mar. 02, 2004
Filed:
Oct. 04, 2001
Helmut Schäfer, Ketsch, DE;
Bruno Hoess, Ottersweier, DE;
Michael Poehlman, Charlotte, NC (US);
Deere & Company, Moline, IL (US);
Abstract
A control device for the parking brake of a motor vehicle has a hydraulic cylinder with a piston chamber that can be pressurized by means of a valve arrangement, and has a hydraulic piston connected mechanically to engagement elements of the parking brake. The parking brake is forced into an engaged or disengaged position depending on the hydraulic pressure in the piston chamber. The piston chamber connects to a pressure sensor providing pressure signals that represent the state of the parking brake and that are evaluated by an electrical control unit. The control unit defines a first predetermined pressure threshold corresponding to the engaged state of the parking brake, and a second predetermined pressure threshold corresponding to the disengaged state of the parking brake.