Fluid-pressure and analogous brake systems – Speed-controlled – Having a valve system responsive to a wheel lock signal
Reexamination Certificate
1999-12-14
2001-10-30
Schwartz, Christopher P. (Department: 3613)
Fluid-pressure and analogous brake systems
Speed-controlled
Having a valve system responsive to a wheel lock signal
Reexamination Certificate
active
06309031
ABSTRACT:
FIELD OF THE INVENTION
The present invention generally relates to vehicle braking and, more particularly, to a variable brake system that adjusts to conform to the needs of the vehicle operator.
BACKGROUND OF THE INVENTION
Conventional vehicle braking systems employ a brake pedal assembly having a brake pedal coupled to a master cylinder. The brake pedal is actuated by the vehicle operator to control the amount of braking torque applied to the wheels of the vehicle via friction braking with the use of hydraulic pressure or electromechanical force. In a brake-by-wire braking system, where the operator's braking request is generally independent of the brake torque, certain characteristics of the brake pedal are sensed and processed in accordance with a predetermined operating curve. For example, brake systems commonly employ either a stroke position sensor to sense the travel displacement of the brake pedal or a pressure sensor to sense the amount of pressure in the brake master cylinder, while some brake systems employ both sensors. An electronic brake controller processes the sensed information, computes the braking torque requested, and generates a control signal to control the amount of torque applied to the brakes of the vehicle. In conventional brake systems, the brake feel characteristics, which may include pedal force versus pedal travel, deceleration versus work, stiffness versus work, deceleration versus pedal force, and deceleration versus pedal travel, are typically permanently defined.
The aforementioned conventional brake system characteristics are generally fixed and therefore cannot be adjusted to accommodate various needs of different drivers. Instead, the position of other accessories in the vehicle, such as the driver's seat, the steering wheel, and the brake and accelerator pedal assembly, may be adjusted to allow the driver to select a preferred position that accommodates the driver's stature and comfort. Despite adjustments of the aforementioned vehicle accessories, the brake pedal must still be actuated with the same amount of effort and pedal travel to achieve the same braking effect. The brake system therefore does not fulfill all the needs for certain vehicle operators. For example, operators who are generally shorter in height may prefer a shortened brake pedal travel to compensate for their lower pedal force and pedal travel to achieve a certain braking torque or deceleration, while taller operators typically prefer an extended brake pedal travel and force to achieve the same braking torque or deceleration.
One approach for adjusting the braking effort in a vehicle is set forth in U.S. Pat. No. 5,378,052, which discloses an electronic brake pedal adjustment apparatus for setting certain braking characteristics by providing the driver with a manual input in the form of a slide control input device, so that the driver of the vehicle can manually adjust the desired braking characteristics. The apparatus of the aforementioned issued patent requires a separate manual input device that requires the driver of the vehicle to first determine the need for a change in braking effort, and then to physically adjust the input device to achieve the desired braking characteristic. Accordingly, the driver may have to manually readjust the manual input, particularly when different drivers having different anatomical dimensions use the same vehicle. In addition, the driver generally may not be accustomed to adjusting the input to the most advantageous position.
Accordingly, there is a need for a variable brake system in a vehicle that adjusts the braking effort to accommodate the needs of the driver.
SUMMARY OF THE INVENTION
In accordance with the teachings of the present invention, a vehicle brake system is provided which offers automatic variable brake effort control. The brake system includes a brake pedal assembly, a brake pedal sensor for sensing effort applied to the brake pedal assembly and generating a signal indicative thereof, and a brake actuator for generating braking force to be applied to one or more brakes on the vehicle. The brake system further includes a position sensor for sensing position of an object in the vehicle, such as a seat position sensor, a steering wheel position sensor, or an adjustable brake pedal position sensor, and generating a position signal which is generally indicative of the stature or comfort of the driver. The brake system further includes an electronic controller for receiving the sensor inputs and automatically controlling the amount of braking force applied to the one or more brakes on the vehicle as a function of the sensed brake pedal signal and the sensed position signal. Accordingly, the brake system of the present invention automatically adjusts the braking effort based on the sensed position signal.
These and other features, advantages and objects of the present invention will be further understood and appreciated by those skilled in the art by reference to the following specification, claims and appended drawings.
REFERENCES:
patent: 3643525 (1972-02-01), Gibas
patent: 4655505 (1987-04-01), Kashiwamura et al.
patent: 4655511 (1987-04-01), Leiber
patent: 4776643 (1988-10-01), Leiber
patent: 4818036 (1989-04-01), Reinecke
patent: 5172785 (1992-12-01), Takahashi
patent: 5378052 (1995-01-01), Yoshino
patent: 5408899 (1995-04-01), Stewart
patent: 5460061 (1995-10-01), Redding et al.
patent: 5513107 (1996-04-01), Gormley
patent: 5555495 (1996-09-01), Bell et al.
patent: 5697260 (1997-12-01), Rixon
patent: 5771752 (1998-06-01), Cicotte
patent: 5816667 (1998-10-01), Jokic
patent: 5819593 (1998-10-01), Rixon et al.
patent: 6007160 (1999-12-01), Lubbers et al.
patent: 6012007 (2000-01-01), Fortune et al.
patent: 6078854 (2000-06-01), Breed et al.
patent: 6099030 (2000-08-01), Kraft
patent: 6099086 (2000-08-01), Feigel et al.
patent: 6104296 (2000-08-01), Yasushi et al.
patent: 6129168 (2000-10-01), Lotito et al.
patent: 6134492 (2000-10-01), Breed et al.
Crombez Dale Scott
Lotito Dave James
Pate Steven Otis
Shehan Mark Alan
Brown Gregory P.
Coughlin William J.
Ford Global Technology, Inc.
Nguyen Xuan Lan
Schwartz Christopher P.
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