Abstract: The present invention relates to a position indicator for displaying the position of a piston (3) within a cylinder (1) as part of a piston-and-cylinder assembly (1, 3) in a brake system. The provision of a Hall element for a hydraulic generating cylinder is known in the art, with the Hall sensor mounted on the cylinder and a ring magnet mounted on the piston. An object of the invention is to describe a position indicator for a brake system, which has a simple construction and is able to provide signals relating to the position of the brake pedal relatively rapidly. This object is achieved because a Hall element of a Hall sensor (12) is placed in the cylinder wall (1) of the master cylinder, and because a magnetic zone (9) is arranged in the piston-and-cylinder assembly so that the Hall element responds to the piston movement within the cylinder.

Abstract: The present invention discloses an arrangement for attaching a brake force booster, that is operable by a push rod, to the splashboard of an automotive vehicle by means of an adapter, wherein a sealing element is interposed between the adapter and the splashboard which additionally is in a radially sealing abutment with the push rod. In order to ensure the correct positioning of the sealing element during the assembly of the brake force booster, the present invention arranges for the brake force booster to include at least one connecting bolt having attaching elements at its ends for attaching the brake force booster to the adapter and for attaching a master brake cylinder connected downstream of the brake force booster to the booster housing, and the adapter has at least one recess which accommodates the attaching element associated with it, and the sealing element includes at least one guide bush which is adapted to be slipped on the attaching element.

Abstract: The invention involves the separation of actinides and lanthanides by membrane transport by means of a calixarene. To this end, a first aqueous solution containing at least one metal from the group of actinides and lanthanides to be separated is placed in the compartment 3 and a second aqueous re-extraction solution such as a 10−2 mol/L solution of HNO3 is placed in the compartment 5. The membrane 6 is a microporous membrane of which the pores are filled with a liquid organic phase (calixarene and diluent) chosen in order to favour membrane transport of the metal(s) to be separated from compartment 3 to compartment 5.

Abstract: The invention relates to novel calixarenes of formula: ##STR1## in which m is equal to 0 or 1, n is an integer from 2 to 8, with 4.ltoreq.n(m+1).ltoreq.8,R.sup.1 and R.sup.2, which can be the same or different, are alkyl or O-nitrophenoxyalkyl groups andR.sup.3 and R.sup.4, which can be the same or different, are alkyl or aryl groups.The calixarenes can be used for extracting actinides and lanthanides from aqueous solutions from spent fuel reprocessing.

Abstract: To prevent a rolling diaphragm (13), which forms the movable wall (4) of a vacuum brake booster along with a metallic diaphragm disk (12), from becoming detached from an annular groove (52) accommodating a radially inner bead (32) of the rolling diaphragm (13), the rolling diaphragm is connected to the edge of the bead (32) located away from the (first) diaphragm disk (12). By connecting the rolling diaphragm (13) to the edge of the bead (32) located away from the (first) diaphragm disk (12), a pneumatic space (27) is defined by the rolling diaphragm (13) and the (first) diaphragm disk (12). Pressure occurring in the vacuum chamber(s) (28, 30) can be admitted to the pneumatic space (27).

Abstract: To infinitely variably adjust the distance between a reaction disc and an interacting second part of a bipartite valve piston in a completely assembled vacuum brake power booster, which is already mounted to the automotive vehicle, a tubular sleeve is provided, arranged coaxially to a piston rod that actuates the valve piston, and is in engagement with a first part of the valve piston, connected with the second part by a threaded union, to apply a torque to the first piston part. For this purpose, the sleeve has at its end projecting from the control housing with an extension permitting rotation of the sleeve.

Abstract: A construction and fabrication process for a two piece vacuum brake power booster housing is described which eliminates the surface tensions which are caused by forming during assembly to prevent damage to a protective surface finish. Localized radially weakened zones are each formed by two opposing tongues created by circumferential and axial slots which tongues in the assembled condition of the housing engage behind an outwardly and reversely formed rim (3) of the other housing half (1).

Abstract: A vacuum brake power booster and a process is disclosed in which a precise adjustment of the power boost startup characteristic is achieved. The adjustment is carried out as a final step in the manufacture of the booster adjusting the distance between the valve piston and an elastic reaction distance. During adjustment, the vacuum brake power booster has a vacuum applied. A pre-established input force is exerted on the piston rod while simultaneously measuring the output force exerted by the push rod, and the axial length of the valve piston is modified until the measured output force is within a pre-established range. The adjustment is carried out by modifying the length of a two piece valve piston or by temporarily extending a rod within the valve piston until a correct output force is reached and thereafter removing the rod and inserting a transmission pin of a length determined by the extent of travel of the rod at the point at which the desired output force was attained.

Abstract: A vacuum brake power booster is described wherein the return movement of a valve piston actuating a control valve is limited by a U-shaped element (17) slidable into a control housing (11). In order to improve the ventilation of the working chamber of the brake power booster initiated on actuation and to shorten the booster's response time, exit areas (42, 43, 44, 45) of ventilation ducts (38, 39, 40, 41) permitting an air flow into the working chamber (3) are formed radially outwardly of an area in the control housing (11) between the arms of the U-shaped element (17), the exit areas being confined by the outside walls (34, 35, 36, 37, 46, 47, 48, 49) of air evacuation ducts (28, 29, 30, 31) interconnecting the working chamber (3) and a vacuum chamber(4).

Abstract: Hydraulic brake systems are known wherein, for the purpose of brake control, a counterforce is built up in the booster (60) for actuation of the master brake cylinder which results in unloading the master brake cylinder. What is disadvantageous in the known system is that this counterforce also resets the pedal (pedal piston 3) so that vehement pedal movements will result from the control action. Therefore, our present invention suggests to interpose a transmission device (3, 4, 5, 6, 7) between the pedal and the actuator (booster) enabling to decouple actuator and pedal.

Abstract: In order to reduce the number of component parts required for the simultaneous ventilation of two power chambers of a tandem brake power booster and to avoid sealing problems. A booster, according to the invention, provides for the transmission of the boosting power of the master cylinder-side movable wall of the booster to be directly to the control housing.

Abstract: 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.

Abstract: 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.

Abstract: An anti-locking automotive vehicle braking unit wherein to achieve a reduction of the costs of manufacture and of mounting with an increase of reliability in operation, a pneumatic device (39, 40) is provided for venting of the first power chamber (5) and/or evacuation of the second power chamber (6) of the vacuum brake power booster (1) in the event of a slip control action. This renders the boosting power of the vacuum brake power booster effective or ineffective in a direction opposed to the direction of actuation of the master brake cylinder (2).

Abstract: A brake booster is dislosed wherein the risk of damage to the control valve housing of the booster in the area of the support of the guiding sleeve which guides the push rod is precluded. The guiding sleeve of the booster comprises an axial extension which, while accommodating the pressure plate and the reaction disc of the booster is located, in sealing manner, in the axial bore of the control valve housing of the booster.