Fluid-pressure and analogous brake systems – Speed-controlled – Front-rear axle apportioning or speed difference
Reexamination Certificate
1999-09-20
2001-08-21
Butler, Douglas C. (Department: 3613)
Fluid-pressure and analogous brake systems
Speed-controlled
Front-rear axle apportioning or speed difference
C188S349000, C188S18100R, C303S113500
Reexamination Certificate
active
06276767
ABSTRACT:
FIELD OF THE INVENTION
This invention relates to braking force distribution control system and method used with a motor vehicle.
BACKGROUND OF THE INVENTION
Traditionally, an anti-lock brake system, also referred to as a braking force distribution control system is terminated when the system recognizes that a vehicle speed is sufficiently low, i.e., the vehicle speed is slow enough as to not require braking force distribution control system as it comes to a stop. At this point, the braking force distribution control system may be terminated when a brake switch is turned off (from on). Alternatively, a pressure increase pulse is sent for a predetermined number of times n or more than n in a pressure increase mode of a braking force distribution control system. However, when a driver is pumping the brakes, the brake pedal is repeatedly applied and released. Accordingly, the brake switch may not be turned off resulting in continued use of the braking force distribution control system even though the vehicle speed is sufficiently low such that the system should be terminated.
In view of the aforementioned problems, the objective of this invention is to optimize the timing of terminating braking force distribution control system by sensing the shifting of the vehicle load from front to rear wheels on the basis of the estimated deceleration of front and rear wheels.
SUMMARY OF THE INVENTION
A hydraulic system and method for effectively initiating a vehicle's braking force distribution control system is disclosed. The method comprises (1) comparing estimated wheel determined at a current and a previous cycle; and (2) initiating the braking force distribution controls (which controls inlet and outlet valve of the rear wheel) when (a) the current estimated wheel deceleration is greater than the previous estimated wheel deceleration, (b) the difference of (a) continues for a predetermined number of cycles and (c) deceleration of the front wheel becomes less that the deceleration of the rear wheel.
Another embodiment of the braking force distribution control method of the invention is also disclosed. The method is carried out using a brake hydraulic pressure device for a motor vehicle which device includes a hydraulic unit. The hydraulic unit is comprised of a main hydraulic circuit connecting master cylinder to a wheel cylinder via an inlet valve. The hydraulic unit also comprises an auxiliary hydraulic circuit which connects an auxiliary reservoir to the wheel cylinder via an outlet valve. An electronic control device controls the hydraulic unit in accordance with the method of the invention. Specifically, the braking force distribution control, which controls the inlet and outlet valves for the rear wheels is initiated. Initiation occurs when the deceleration of a front wheel is determined to be less that the deceleration of a rear wheel.
An object of the invention is to provide a system and method which effectively terminates the brake force distribution control system when specific conditions are present.
An advantage of the invention is that it can be readily integrated into a conventional hydraulic brake system.
A feature of the invention is that it operates by controlling inlet and outlet valves of a rear wheel cylinder
These and other objects and advantages and features of the present invention will become readily apparent by reference to the following detailed description when considered in conjunction with the accompanying drawings.
REFERENCES:
patent: 4505520 (1985-03-01), Maehara
patent: 5620239 (1997-04-01), Mihara et al.
patent: 5624164 (1997-04-01), Tozu et al.
patent: 5634699 (1997-06-01), Ichikawa et al.
patent: 5640324 (1997-06-01), Inagaki
patent: 5641209 (1997-06-01), Kushi et al.
patent: 5646849 (1997-07-01), Walenty et al.
patent: 5676434 (1997-10-01), Ichikawa et al.
patent: 5697682 (1997-12-01), Watanabe et al.
patent: 5700074 (1997-12-01), Sugimoto et al.
patent: 5711585 (1998-01-01), Tozu et al.
patent: 5752211 (1998-05-01), Takasaki et al.
patent: 5752752 (1998-05-01), Tozu et al.
patent: 5758930 (1998-06-01), Schiel et al.
patent: 5762406 (1998-06-01), Yasui et al.
patent: 5772289 (1998-06-01), Nakazawa et al.
patent: 5795039 (1998-08-01), Fennel et al.
patent: 5806939 (1998-09-01), Feigel et al.
patent: 5810455 (1998-09-01), Noguchi
patent: 5810456 (1998-09-01), Inagaki et al.
patent: 5826954 (1998-10-01), Schmitt et al.
patent: 5829847 (1998-11-01), Tozu et al.
patent: 5842755 (1998-12-01), Sugimoto et al.
patent: 5853229 (1998-12-01), Willmann et al.
patent: 5857754 (1999-01-01), Fukami et al.
patent: 5860710 (1999-01-01), Takemasa
patent: 5869943 (1999-02-01), Nakashima et al.
patent: 5882093 (1999-03-01), Enomoto et al.
patent: 5887957 (1999-03-01), Büttner et al.
patent: 5913578 (1999-06-01), Tozu et al.
patent: 5927830 (1999-07-01), Tozu et al.
patent: 5931546 (1999-08-01), Nakashima et al.
patent: 5938299 (1999-08-01), Hara et al.
patent: 5947221 (1999-09-01), Taniguchi et al.
patent: 5947224 (1999-09-01), Kouno
patent: 5951115 (1999-09-01), Sakai et al.
patent: 58-156443 (1983-09-01), None
patent: 2212248 (1990-08-01), None
Bozicevic Field & Francis LLP
Butler Douglas C.
Cannon, Esq. Alan W.
Nisshinbo Industries Inc.
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