Fluid-pressure and analogous brake systems – Speed-controlled – Having a valve system responsive to a wheel lock signal
Patent
1989-12-11
1992-10-13
Graham, Matthew C.
Fluid-pressure and analogous brake systems
Speed-controlled
Having a valve system responsive to a wheel lock signal
303116R, 303 D4, B60T 840, B60T 844
Patent
active
051544954
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
The present invention relates to a process for operating a master cylinder of a brake pressure control system, in particular, an anti-locking control system (ALC-system), or a traction slip control system (TSC-system), for use with automotive vehicles. The control system comprises at least one pump the rate of delivery of which is variable and which, in the control mode, serves to position at least one working piston of the master cylinder. The control system further comprises a pressure modulator modulating the pressure in the wheel cylinders during the control mode, and comprises an electronic controller processing wheel sensor signals to form regulating signals for the passage and blocking valves of the pressure modulator.
Anti-locking control systems are increasingly being used in the automotive industry. In these systems the hydraulic pumps for generating an auxiliary pressure, in the control mode, are employed. An anti-locking control system of this type is disclosed, for example, by German Patent Application P 37 31 603.6. This patent application describes a brake system, for use with automotive vehicles, comprising a master cylinder, wheel cylinders and an anti-locking control means. For positioning the piston of the master cylinder in a desired position in the control mode, a pressure fluid source, preferably a pump of a variable rate of delivery, is used which is in communication, through a hydraulic conduit, with the master cylinder and which, through its rate of delivery, positions the piston.
A problem with these known systems is that during the control mode, especially during the ALC- or TSE-mode, the pedal must be restored in a controlled manner. The position thereof, during the control mode, should be advanced relative to the normal initial position. Accordingly the so-called pedal "feel" is improved in accordance with the present invention while enhancing the safety of the entire system. Moreover, it is an object of the present invention to avoid the prior art sensors within the area of the booster or pedal, as in German Patent Application P 37 31 603.6.
SUMMARY OF THE INVENTION
It is therefore an object of the invention to have the control of the pedal positioning performed by elements provided in the area of the master cylinder. This provides a substantial manufacturing advantage, and decreases the manufacturing costs as no additional structural efforts are required in the area of the booster of the pedal work or the pedal itself. The structural efforts are reduced while the operating safety is enhanced. The customary gear-shift levers or sticks are eliminated. Accordingly the provision of additional brake conduits and additional valves is avoided. Moreover, a simplified assembly is attained. Further, the so-called pressure switch required by state-of-the-art brake pressure control system in the traction slip control mode is avoided.
In this respect, conventional brake pressure control systems exhibit a so-called TSC-valve the function of which is to separate, in TSC-mode, the working chamber of the master cylinder from the brake circuit of the actuated axle. The TSC-valve is, therefore, also designated by TSC-blocking valve. The TSC-valve, in the TSC-mode is, electromagnetically actuated, receiving its switching signal from the electronic controller and blocking, in the TSC-mode, the hydraulic pressure conduit leading from the master cylinder to the pressure modulator of the brake pressure control system. This pressure switch is a safety element. Once the brake pedal is applied, in the TSC-mode, the pressure in the master cylinder can be increased beyond the permitted level. The pressure in the master cylinder is sensed by the pressure switch. Once the permitted pressure threshold is exceeded, the pressure switch supplies a signal to the electronic controller. The electronic controller then causes, by failure to activate the actuating magnet of the TSC-valve, the TSC-valve to be returned to its open position corresponding to the resting position. This wil
REFERENCES:
patent: 3823985 (1974-07-01), Hubbard
patent: 4779937 (1988-10-01), Burgdorf et al.
patent: 4820255 (1989-05-01), Volz
patent: 4919493 (1990-04-01), Leiber
patent: 4919496 (1990-04-01), Buregdorf et al.
patent: 5039175 (1991-08-01), Holzmann et al.
Alfred Teves GmbH
Graham Matthew C.
Lewis J. Gordon
Seitter Robert P.
LandOfFree
Process (of) for operating a master cylinder does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process (of) for operating a master cylinder, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process (of) for operating a master cylinder will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1296132