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. 19, 1991
Filed:
May. 17, 1989
Naila Mikhaeil-Boules, Troy, MI (US);
Robert J Hammersmith, Rochester Hills, MI (US);
Kevin G Leppek, Troy, MI (US);
Paul D Wilkey, Vandalia, OH (US);
Thomas H Gardner, Englewood, OH (US);
Dennis J Ricker, Huber Heights, OH (US);
James J Kowalik, West Carrollton, OH (US);
General Motors Corporation, Detroit, MI (US);
Abstract
A vehicle wheel anti-lock braking system (ABS) is provided including a master cylinder and a wheel brake. An ABS controller cognizant of the rotational condition of the wheel provide a signal when the wheel condition is within preset parameters. An isolation valve responsive to close upon an activation signal given by said controller prevents fluid communication between the master cylinder and the wheel brake. An actuator frame is also provided having a bore fluidly communicating with the wheel brake. A piston is mounted within the bore for providing a variable control volume in communication with said wheel brake for and modulating the pressure therein. A reversible motor reciprocally powers piston. The motor has a rotor with a connected disc. A friction surface is provided for engagement with the disc to lock the position of the piston. A plunger is also provided to urge said friction surface into engagement with said disc. An electromagnetic core, responsive to a signal by said controller, moves the plunger to a position allowing removal of engagement between said friction surface and said disc thereby allowing rotation of the motor and movement of the piston.