Alfred Teves Gmbh

Itt Industries, Inc.

Peter Boehm

Wilfried Wagner

Rolf Weiler

Ralf Jakobi

Lothar Schiel

Kai-Michael Graichen

Gilbert Bischoff

Peter Volz

Karlheinz Timtner

Jurgen Bauer

Kurt Saalbach

Lucas H Haar

Manfred Rueffer

Klaus Bergelin

Hermann Seip

Albin Loew

Reimund Becht

Karl Breitwieser

Hans-Juergen Beilfuss

Bernd Toepperwien

Sigmund Booten

Klaus Engert

Lothar Mattheis

Housing for a pneumatic power booster and process for its manufacture

A vacuum brake power booster, in particular for motor vehicles, which includes a poppet valve (12) sealing two valve seats (18, 19) and which is axially deformable within the area of a rolling fold (15) also includes an annular part which is either mounted on the outside of the rolling fold (15) in a form-fit manner or arranged inside the elastic material (24) of the poppet valve (12). This annular part prevents the rolling fold (15) from being blown up outwardly due to the pressure differential prevailing between its two sides so that it will be possible to reduce the return force and thus also the response force.

Vacuum brake power booster, in particular for motor vehicles

In order to simply and economically fix to an internal-thread coupling (12) a pipeline (17) furnished with two slidable external-thread connections (15, 18), the invention contemplates fabricating the two external-thread connections (15, 18) together in the shape of one part only. At a predetermined screw-in torque, one external-thread connection (15) is torn off and as a result one pipeline end (16) is safely retained in the internal-thread coupling (12). The second external-thread connection (18) may be slid to the second end (21) of the pipeline and can fix the latter to a further internal-thread connection. The fixing means and methods contemplated by the invention are automation compatible and, upon fixing, protect the pipeline from being detached from the coupling through faulty handling.

Methods and apparatus for fixing a pipeline to a coupling

A process for the precise adjustment of the lost travel of a piston in a master cylinder. Master cylinders typically include a number of components in spatial series arrangement, with all components having individual tolerances. The individual tolerances regarding the lost travel of the piston or pistons, can combine additively in the master cylinder. The resulting lost travel, hence, is relatively large and varies with individual master cylinders. The process provides that the lost travel of the piston or pistons in the master cylinder can be precisely adjusted and, hence, can be kept very low. The position of the piston or pistons is measured in the condition in which they just seal the associated equilibrium ports. Subsequently, the position of the pistons is calculated in consideration of the desired lost travels and, by adjustment of the force planes acting on the desired point, the resting position of the piston and pistons, respectively, is fixed to the desired distance. Moreover, the process determines, in a simple manner, the position of the piston in which the piston by means of its sleeve, just seals the associated equilibrium port.

Process of precisely adjusting the lost travel of at least one piston in

As an improvement on conventional brake systems of the type having a multiple-chamber vacuum brake force booster, a modification is disclosed to the effect that, in the brake releasing position, there is a pressure medium communication between a booster chamber and a simulator chamber. A modulator chamber requires only one external connection, thereby substantially simplifying the construction of the brake force booster and readily permitting an extension of the system's use to include traction slip control.

Brake system for automotive vehicles and brake force booster therefor

In order to enable a brake booster to operate both with a pressure above atmospheric and with atmospheric pressure without any negative mutual influences of the two energy types and without any change in the responding behavior of the device in case of failure of either energy type, the invention provides a pneumatic system which, during the operation of the brake booster with pressure above atmospheric, causes a force constituent to become active so as to counteract the forces caused by the increased pressure difference and acting on the control valve piston as well as on the control valve housing.

Brake booster

A vacuum brake booster in which the guiding sleeve (14) for the push rod (29) has an annular ring which defines a cylindrical guiding surface (22) and is guided, in axial movements of the guiding sleeve, by a guide bore in the housing (10) of the control valve.

Vacuum brake booster for automotive vehicles

In a power brake booster for an automotive vehicle, with a housing (1, 2) subdivided into two compartments by a partition wall (41), the compartment close to the brake pedal contains a working chamber (25) and a vacuum chamber (33), while the compartment close to the master cylinder contains a working chamber (24) and a vacuum chamber (32), with a longitudinally slidable control housing (4) with valve device (8, 37, 38) being sealably held and guided in a central opening of the partition wall (41), the said control housing incorporating a longitudinal channel, for instance on annular gap (21) which, on the one hand, is via an opening or bore (26) in communication with the one working chamber (24), while, on the other hand, it terminates into a chamber, for example an annular chamber (20), which is connected to the valve chamber (42) behind the valve device (8, 37, 38) and which is connected to the other working chamber (25) via a cross bore (39). Through the valve device (8, 37, 38), the annular gap (21) is connected to another channel (34) which is provided in the control housing (4) and is in permanent communication with the suction port (11) so that both working chambers (24, 25) are connected both to the vacuum source and to the outside air through channels (34, 36 and 20, 19, 21, 26, 39, respectively) provided in the control housing (4).

Power brake booster for an automotive vehicle

A vacuum operated brake power booster including a retaining member for securing the edge bead of a moveable wall diaphragm of the booster to the booster control valve is disclosed. The booster includes a casing subdivided into two chambers by a moveable wall having a diaphragm which has an internal edge bead disposed in an annular groove in the control valve housing of the booster. An annular retention ring surrounds the bead of the diaphragm to the outside of the bead and radially retains the edge bead within the control valve housing groove.

Vacuum-operated brake power booster having diaphragm edge bead retention

A vacuum-operated brake power booster is provided having a movable wall which is sealed off relative to the vacuum housing and a control valve body which is slidable jointly with the movable wall. A hollow cylinder-shaped expanded plastic ring is arranged in the annular clearance between the neck portion of the pedal side housing shell and the collar of the diaphragm, which collar sealingly surrounds the control valve body. The expanded plastic ring effects the air flow during brake operation such that the air flow, enters the annular clearance through the duct extending in a radial direction within the control valve body and is suitably deflected and cushioned so that no noises arise at this point. In the same manner and simultaneously, vibrations, especially those of the neck portion of the housing shell of the vacuum housing, are suppressed, since the expanded plastic ring adheres to the inside wall of the housing shell.

Vacuum-operated brake power booster

In a vacuum-operated brake power booster, a transverse member is provided which confines the axial movability of the control piston relative to the control housing. The transverse member abuts against a bead of a rubber-elastic material, the bead forming part of the slide-guide ring sealing the booster housing relative to the control housing. The tranverse member is formed of a substantially U-shaped sheet-metal blank, with both free ends of the fork arms extending parallel to two limbs of the member. The arms are provided with hook-shaped tabs which are bendable around a pin forming part of the control housing for the purpose of fixing the transverse member in its aperture in the control housing. In order to enable a proper and easy bending of the tabs during assembly, notches are provided at the radially outside small faces or edges of the two fork arms.

Differential pressure brake boosters are known having a reinforcement tube extending axially through the low-pressure casing with its ends fastened to both end surfaces of the casing. A mechanically actuated control valve for connecting the working chamber to the low-pressure chamber or to atmosphere is axially movable in the reinforcement tube. A sleeve surrounding a master cylinder piston push rod has radial ribs extending through longitudinal slots of the reinforcement tube to connect the push rod to the movable wall. These ribs are subjected to a high bending stress. According to the present invention the radial ribs are constructed as flat tongues disposed in a common plane, the tongues being engaged on a side thereof adjacent the low-pressure chamber by an outwardly angled collar of an extension of the housing of the control valve. The distance between the rolling diaphragm of the movable wall adjacent the reinforcement tube and the end of the longitudinal slots adjacent the work chamber is at least equal to half the power stroke of the axially movable wall.

Brake boosters for automotive vehicles

A low-pressure casing for a brake booster for automotive vehicles comprising two casing shells. A central ring flange is located at the inner surface of the end wall of each of the two casing shells. The portion of each end wall lying outside the ring flange is of truncated-cone-shaped construction and merges into a cylindrical circumferential casing section. At each of these merger points, a prop ring is inserted to bear against the inner surface of the associated one of the two casing shells.

Low pressure casing for a brake booster

A brake booster for automotive vehicles comprises a low-pressure casing sealingly subdivided into a low-pressure chamber and a working chamber by an axially movable wall. The two transverse end walls of the low-pressure casing are interconnected by a central reinforcement tube integrally formed with a master cylinder. The actuating piston of the master cylinder is connected to a guide piston which is guided in the reinforcement tube and which receives a rubber-elastic reaction disc in an end thereof remote from the master cylinder. A control valve casing is axially movable in the reinforcement tube, bears axially against the reaction disc and is connected to the movable wall by radial ribs extending radially through longitudinal slots in the reinforcement tube. The radial ribs are connected to a ring which encompasses the reinforcement tube and which is secured in a bowl-shaped hub member of the movable wall. Air channels extend through the radial ribs to connect a control valve in the control valve casing to the low-pressure chamber.

Brake booster for automotive vehicles

The pre-assembled two-stage reaction device for a vacuum brake booster includes reaction levers which are in engagement with the booster movable wall at a first location and with the master cylinder push rod and a reaction plate connected thereto at a second location, with the first location being arranged radially farther out than the second location. The reaction levers are acted upon by a cup spring at a third location, with the cup spring being positioned on the side of the reaction levers adjacent a vacuum chamber and with the third location having a greater radius than the first location. A spring plate is arranged between the cup spring and the reaction levers whose circumferential collar is provided with flattened portions for the reaction levers on the side adjacent the reaction levers. To create a two-stage reaction device which can be pre-assembled and can also be employed in boosters having control housings made of thermoplastic material, there is arranged a supporting ring with two inward supporting edges upon which the reaction levers abut whose inner ends are tiltable about the supporting edges in the direction of the control valve, and with the reaction levers, the push rod with the reaction plate, the spring plate and the cup spring being retained together by the supporting ring on the one side and by a circular guide element connected thereto on the other side.

Growing community of inventors

Frankfurt am Main, Germany

Peter Boehm