Fluid-pressure and analogous brake systems – Speed-controlled – Having a valve system responsive to a wheel lock signal
Patent
1994-06-15
1996-03-05
Oberleitner, Robert J.
Fluid-pressure and analogous brake systems
Speed-controlled
Having a valve system responsive to a wheel lock signal
251 80, 25112919, 2511292, B60T 836
Patent
active
054961009
DESCRIPTION:
BRIEF SUMMARY
PRIOR ART
The invention is based on a solenoid valve with a pressure limitation for motor vehicle brake systems with slip control.
In the case of an already proposed solenoid valve of this type (German Patent Application P 41 29 638.9), the valve tappet is guided at its front end, bearing the valve element designed as a ball, in a guide sleeve fastened in the valve housing. The restoring spring, acting in the opening direction of the solenoid valve, is supported as a helical compression spring on the one hand against the guide sleeve and on the other hand, on the side facing away from the valve element, against the valve tappet. The pressure-limiting spring is arranged in a bore in the armature of the electromagnet, which bore is coaxial to the valve tappet, and is supported as a helical compression spring against a spring plate which is movable in the armature. The spring plate can be pressed on the one hand against the end face of the valve tappet facing away from the valve element and on the other hand against a stop provided on the armature. If the electromagnet is excited, the armature is attracted, as a result of which the pressure-limiting spring acts on the valve tappet, which is movable in relation to the armature, and displaces the said tappet against the force of the restoring spring in the direction of the valve seat and sets the valve element onto the valve seat. The force pressing the valve element onto the valve seat, which force determines the opening pressure of the solenoid valve in the closing position of the latter, is dependent on the bias or rating of the pressure-limiting spring and of the restoring spring.
ADVANTAGES OF THE INVENTION
The solenoid valve according to the invention has the advantage that, due to the shifting, according to the invention, of the pressure-limiting spring out of the armature of the electromagnet into the valve tappet and the associated elimination of the coaxial bore in the armature for receiving the pressure-limiting spring, a greater armature pole face is available and consequently a greater magnetic force is available with an electromagnet of the same rating. The stop face of the armature on the valve housing can be designed optimally with respect to the radius of a capsule which is held on the valve housing and receives the armature, in order to avoid capsule ruptures under continuous stress.
The solenoid valve according to the invention has a simple structural design and can be set and adjusted much more simply and accurately. By virtue of its type of design, it can be assembled in a forward assembly, assembly and setting proceeding sequentially. This saves assembly time and helps to conserve assembling and operating means.
Advantageous further developments and improvements of the solenoid valve are possible by the measures set out hereinafter.
In a preferred embodiment of the invention, the valve seat is formed on a valve body press-fitted in a sleeve-shaped valve housing. Of the valve tappet designed in two parts, the tappet element which can be driven by the electromagnet is guided axially in the valve housing and is of an at least partially hollow-cylindrical design, the other tappet element, bearing the valve element, being accommodated axially displaceably in the hollow-cylindrical tappet element. The restoring spring is supported between the valve body and the hollow-cylindrical tappet element and brings the latter to bear against an armature of the electromagnet, while the pressure-limiting spring, arranged between the tappet elements, brings the tappet element bearing the valve element to bear against a stop formed on the hollow-cylindrical tappet element. Due to these design measures, the setting of the opening pressure is governed only by the pressure-limiting spring and not, as in the case of the known solenoid valve, also in addition by the restoring spring. The spring setting can consequently take place more accurately and can be reproduced better. Together with the better-defined stop faces of the armature on the valve housing, vari
REFERENCES:
patent: 2296132 (1939-05-01), Wiseley
patent: 3818927 (1974-06-01), Zeuner
patent: 4526203 (1985-07-01), Leiber
patent: 5318066 (1994-06-01), Burgdorf et al.
Greigg Edwin E.
Greigg Ronald E.
Oberleitner Robert J.
Robert & Bosch GmbH
Young Lee W.
LandOfFree
Pressure limited solenoid valve for a brake system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Pressure limited solenoid valve for a brake system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Pressure limited solenoid valve for a brake system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1408251