Brakes – Wheel – Axially movable brake element or housing therefor
Patent
1996-09-13
1999-02-09
Oberleitner, Robert J.
Brakes
Wheel
Axially movable brake element or housing therefor
188 726, 188 729, 188 719, F16D 5518
Patent
active
058682252
DESCRIPTION:
BRIEF SUMMARY
The present invention relates to a brake actuator comprising : a substantially cylindrical body filled with a hydraulic fluid which is subjected to a variable pressure; a mechanical actuating means including two plates for relative rotation forming an assembly which presents, in an axial direction, a thickness which is adapted to be controlled by the actuation of a control member which is accessible from the exterior of the body; a brake piston which closes off the body sealingly and is adapted to slide therein in response to the action of the actuating means to actuate in turn at least one friction means; and an automatic adjustment device disposed within the body between the mechanical actuating means and the piston to compensate for play resulting, from wear of the friction means, this device itself comprising a selectively rotatable screw, onto a first end of which is engaged an elongated nut which is rotationally fixed; a prestressed spring which applies a first end of the nut against at least one of the plates; and a retention member against which the spring bears and which urges together the at least one plate, the first end of the nut, and the spring; the second end of the screw being engaged into an orifice formed in the piston, which it closes off sealingly so as to be subjected to atmospheric pressure, and which presents a conical shoulder adapted to be selectively locked against rotation by an internal conical surface of the piston, which is fixed rotationally, against which this shoulder is urged with a force which increases with the pressure of the hydraulic fluid.
BACKGROUND OF THE INVENTION
A brake actuator of this kind is known in the prior art, for example from the international patent application document PCT/FR93,00918 (U.S. Pat. 5,586,623.
One of the problems which is encountered in the design of brake actuators, whatever structure they have, consists in ensuring that they have a very high degree of operational reliability in a context of large volume production and reduction of manufacturing) costs.
In particular, it appears more and more to be necessary to provide that the operation of these brake actuators will be irreproachable even when the limits of the manufacturing tolerances are reached.
SUMMARY OF THE INVENTION
The invention has precisely as objective to provide a brake actuator of robust design which meets the current manufacturing requirements for large volume production.
To this end, the brake actuator of the invention is essentially characterised in that in addition to the elements already referred to, it comprises an axial cylindrical sleeve within which the nut is guided by its second end and which is provided with a radial collar trapped between the spring and the retention member
BRIEF DESCRIPTION OF THE DRAWINGS
Other features and advantages of the invention will appear clearly from the description of the invention which is given hereafter, by way of indication and without limitation, with reference to the accompanying drawing which represents, in sectional view, a brake actuator in accordance with the invention
DETAILED DESCRIPTION OF THE INVENTION
The invention relates to a brake actuator comprising an essentially cylindrical body 1 filled with brake fluid which is subjected to a variable pressure, the body being solid with a caliper 2.
A mechanical actuation means 3, comprising a rotary control lever 3a which is accessible from the exterior of the body, is additionally housed within the body.
A brake piston 4 is mounted slidingly within the body I which it closes off sealingly, the displacement of this piston being controlled by the actuating means 3 through a spacer 5 of variable length, and enabling the displacement of two friction members 6a, 6b, of which one is retained by the caliper 2 and the other is pushed by this piston.
The spacer 5, which forms part of an automatic adjustment device designed to compensate the play which results from the wear of the friction members, comprises on one hand an elongate nut 7 which is indirectly locked against r
REFERENCES:
patent: 3638763 (1972-02-01), Laverdant
patent: 4637498 (1987-01-01), Thompson et al.
patent: 4784245 (1988-11-01), Fabbro et al.
patent: 4981197 (1991-01-01), Antony et al.
patent: 5038895 (1991-08-01), Evans
patent: 5586623 (1996-12-01), Mery
patent: 5609227 (1997-03-01), Mery
Bosch System De Freinage
Lipka Pamela J.
McCormick Jr. Leo H.
Oberleitner Robert J.
LandOfFree
Brake actuator with increased tolerance does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Brake actuator with increased tolerance, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Brake actuator with increased tolerance will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1943506