Abstract:
The invention concerns a power-assisted steering unit for a motor vehicle with a steering mechanism functionally linked to the wheels to be steered and operated by a manual steering wheel, as well as with a steering-booster motor (1) which can be caused to act on the steering mechanism. In order to provide a simple-design, cheap-to-manufacture, high reliability unit, and in particular to disengage the steering-booster motor (1) from the steering mechanism when the vehicle is stationary, the invention calls for a centrifugal clutch (3) to be fitted in the motor driven shaft (2) between the motor (1) and the steering mechanism.
Abstract:
The invention relates to a piston pump with suction regulation, especially for motor vehicles, and preferably with a control stub for internal admission. It is the purpose of the invention to provide such a pump with a constant supply flow rate over a wide revolution speed range and the lowest possible losses and low noise level. To this end the present invention proposes several solutions. In a first, the control slot (13) on the pressure side is divided into several grooves (27, 28), which are at least partly connected to the pressure link (20) via non-return valves (32). In another, the shape of the control slot on the pressure side is adapted to the optimum operating mode by making its inlet end relatively narrow to reduce the noise level (noise reduction at high revolution speeds) and keeping an adequate width at the outlet end for the power required. In a third, the arrangement for the slot (12) on the intake side is similar to that of the second solution and its length also affects the degree of filling of the piston drilling.
Abstract:
A power brake for motor vehicles has a control valve (12) which can be actuated by an electromagnet (20) independently of an actuating rod (7) which moves a valve piston (9). The electromagnet (20) actuates a third valve sealing seat (24) which allows the work chamber (3) to be vented. The design of the control valve (12) of the externally controlled power brake is modified to stabilise the characteristic curve of the consumer system formed by the armature (31) of the electromagnet (20), a sleeve (32) which carries the third valve sealing seat (24) and the valve body (10) of the control valve (12), especially in the pressure falling range. For this purpose, means (36, 37, 39) are provided which balance the pneumatic pressure in a controlled (dosed) manner between the work chamber (3) and vacuum chamber (4) or which lower the force to be supplied by the electromagnet (20) during the return of the third sealing seat (24) of the valve body (10) in the pressure falling phase.
Abstract:
A brake system for motor vehicles with a pneumatic brake booster (5) has two chambers. A lower pressure is applied to one of the chambers and a higher pressure is applied to the other chamber. At least one of the chambers may communicate with a pneumatic pump. Means (49) are provided to switch the pump (51, 61, 65) on and off depending on the pressure in the chamber (4, 7) of the brake booster (5) with the pump is associated.
Abstract:
The hydraulic backing, which occurs only above a predetermined steering force, is carried out by means of a working cylinder (6) coupled to a mechanical steering system, a pump (19, 36) and a control valve (12). To provide a servo-assisted steering system which is safe in its operation and simple in its design, the displacement, under the effect of the steering force, against a pretension, of a structural element (2) of the mechanical steering system, mounted slidingly relative to the body of the vehicle, is used for the mechanical actuation of the control valve (12).
Abstract:
A hydraulic system is disclosed with a hydraulic pump directly driven by an internal combustion engine. The object of the invention is to reduce the size, weight, energy consumption and number of components of such known systems. For that purpose, the same pump applies pressure medium to several elements, among which a camshaft adjustment device. Advantageous developments of the invention concern the overriding supply of safety-relevant devices before other devices that are equally linked to the pump. Several measures are disclosed therefor. In addition, the present application describes a series of simplified hydraulic circuits which allow devices having the same order of precedence to be simultaneously driven by one or several pumping circuits. The application also concerns reactionlessly separating individual devices controlled by a pump by distributing them among several separated pumping circuits that may belong to a single pump having one or several pumping stars. Further improvements of the hydraulic system concern an improved energy consumption and noise reduction by certain designs of the pump, wherein the pump is preferably arranged near or within the motor.
Abstract:
The invention concerns a vacuum brake booster with an electromagnetic auxiliary control system, in particular for motor vehicle braking systems. The vacuum brake booster comprises: a booster housing (1) whose interior is divided by a movable inner wall (2) into a working chamber (3) and a vacuum chamber (4); a control housing (5) which can move with the movable wall in the axial direction of the booster housing and has a first sealing seat (8); a sealing body (17) disposed so that it can move axially in the control housing; a valve piston (11) which can be actuated via an actuating rod (7); a valve body (12) which is disposed so as to move axially on the valve piston, comprises a second sealing seat (13) and is pretensioned towards the sealing body (17); an electromagnet (21) which is provided in the control housing; and a reaction disc (19) of resilient material. The valve body can be moved away from the sealing body via the valve piston and/or the electromagnet. Reliable opening of the second sealing seat by the electromagnet is ensured irrespective of the booster ratio at the reaction disc, even when the braking pressure is high, in that provided between the reaction disc and the valve body are devices (24) which reduce a restoring force exerted by the reaction disc with respect to a restoring force which is effective when the actuating rod (7) actuates the valve piston (11) and is transmitted directly to the valve body, bypassing the valve piston.
Abstract:
The proposed brake system has a main cylinder (1) operated via a drive unit (2). The latter is supplied from an electrically actuated pressure source (3) with a pressurised medium. In a so-called boost mode, the pressure is determined by the pedal pathway. For that purpose, a pedal sensor (7) is provided. However, the pressure source (3) also supplies pressurised fluid independently of any pedal operation, so that brake pressure can be increased in the wheel brakes for adjustment operations relating to the longitudinal and transverse dynamics of the vehicle even without the driver operating the brake. The basic concept of the invention is to dispense with a mechanically operated valve in the drive unit (2) and ensure that pressure can be increased both in the event of a pedal operation and of a power-brake operation and is in both cases controlled electronically. The pressure source (3) can also be used to operate a clutch.
Abstract:
In order to achieve an energy saving operation of the hydraulic pump, a variable camshaft adjustment with proportional position regulator is provided with a bypass control position.
Abstract:
The invention relates to a device for actuating the control valve (14) of a hydraulic servo steering system for motor vehicles in which the rotary movement of a steering wheel is transmitted via a control shaft (2) and the steering moment is transmitted via a relative rotation between the control shaft (2) and a pinion shaft (4) and whereby the control valve (14) is a linear slide valve. It is the purpose of the invention to provide a simple device with few components. This is achieved in that there is a sleeve (6) surrounding the control shaft (2) and the pinion shaft (4) which converts the relative rotation between the two shafts into an axial shift owing to the fact that the sleeve (6) has a pair of axially and spirally running connecting link guides (7, 8) with which engage a pair of pins (9, 10) which are solidly secured to the control shaft (2) or the pinion shaft (4). Further embodiments of the invention concern particularly compact or low-friction arrangements. In order to compensate all actuating clearances, it is proposed in an important further embodiment of the invention to fit a prestressing spring (36) to the valve slide (12).