Hydraulic block for a hydraulic unit of a hydraulic vehicle braking system

Abstract

Hydraulic block for a hydraulic unit of a hydraulic vehicle brake system, comprising a master brake cylinder (2) and a further cylinder (7'), characterized in that the further cylinder (7) is arranged centrally in a flat side (18) of the hydraulic block (15) and that the hydraulic block (15) has a pipe passage (23) on a side of the further cylinder (7') facing away from the master brake cylinder (2) in a longitudinal median plane of the hydraulic block (15), which extends from one to the other flat side (18, 20) of the hydraulic block (15), wherein the hydraulic block (15) has connections (4') for wheel brakes (4) in a flat side (18) of the hydraulic block (15) transverse to the master brake cylinder (2).

Description

[0001] The invention relates to a hydraulic block for a hydraulic unit of a hydraulic vehicle braking system, comprising the features of the preamble of claim 1. In particular, the hydraulic block according to the invention is intended for a slip-controlled, hydraulically powered vehicle braking system. Brake pressure for service braking is generated by a cylinder-piston unit, the piston of which is displaced in a cylinder by means of an electric motor and a screw drive. A manually operated master cylinder serves as the setpoint generator for the service braking. Furthermore, in the event of auxiliary braking due to failure of the piston-cylinder unit, brake pressure is generated manually using the master cylinder. State of the art

[0002] Hydraulic blocks are commonly used in slip-controlled hydraulic vehicle braking systems. They are typically low, cuboid metal blocks designed to house hydraulic components such as hydraulic pumps, solenoid valves, check valves, accumulators, and damper chambers of the vehicle's braking system. The hydraulic blocks mechanically support these components and connect them hydraulically via lines typically drilled into the block. A hydraulic block equipped with these components forms a hydraulic power unit and is the core of the traction control system. "Low" in this context means that hydraulic blocks are often approximately 1 / 4 to 1 / 3, and rarely more than half, of their length and width in thickness. In profile, hydraulic blocks appear rectangular and often approximately square. The hydraulic block typically contains only the hydraulic components of the system.Electromechanical components such as the coils and armatures of the solenoid valves protrude from the hydraulic blocks. Similarly, an electric motor for driving the hydraulic pumps is mounted externally on the hydraulic block.

[0003] Such a hydraulic block is known from German patent application DE 10 2006 059 924 A1. The known hydraulic block has receptacles for solenoid valves of the slip control, which are arranged in rows next to each other in the hydraulic block.

[0004] German patent application DE 10 2009 054 985 A1 discloses a hydraulically powered vehicle braking system with a hydraulic block comprising a master brake cylinder, a pedal travel simulator, a cylinder-piston unit for generating brake pressure during service braking, and solenoid valves for slip control. A brake fluid reservoir, like those normally mounted on a master brake cylinder, is attached to one narrow side of the hydraulic block. Disclosure of the invention

[0005] The hydraulic block according to the invention, with the features of claim 1, is intended for a hydraulic unit of a hydraulic vehicle braking system. The hydraulic unit is defined here as the hydraulic block equipped with hydraulic components. In particular, the hydraulic block according to the invention is intended for a slip-controlled, hydraulically powered vehicle braking system. It has a master brake cylinder, which is in particular designed as a stepped bore, arranged in particular parallel to a transverse side of the hydraulic block and open on one or both longitudinal sides of the hydraulic block. Longitudinal and transverse sides are here defined as the lower sides of the hydraulic block, which is in particular cuboid in shape, where the designation serves for unambiguous identification and distinguishability, and the transverse sides may be longer than the longitudinal sides.A further cylinder, used to generate brake pressure during service braking and / or traction control, is centrally located on a flat side of the hydraulic block. Traction control systems include, in particular, anti-lock braking, traction control, and vehicle dynamics / skid control systems, for which the abbreviations ABS, ASR, FDR, and ESP are commonly used. While not the primary objective of the invention, it is possible to use the hydraulic block for a manual or power-assisted vehicle braking system, in which brake pressure is generated by muscle power with the master brake cylinder, possibly with external power assistance, and the further cylinder serves to generate brake pressure during traction control.

[0006] The invention provides a hydraulic unit, i.e., a hydraulic block equipped with a brake fluid reservoir mounted on one transverse side within a cylinder with a diameter of less than 23 cm (9 inches), wherein one cylinder axis runs parallel to a master cylinder axis of the hydraulic block. This corresponds to the diameter of a vacuum reservoir of a typical car vacuum brake booster.

[0007] The claims relate to an advantageous bore in the hydraulic block and a compact arrangement of the hydraulic components and their electrical connections. Further features of the invention will become apparent from the following description of an embodiment of the invention in conjunction with the claims and the drawing. The individual features can be implemented individually or in any combination in embodiments of the invention, whereby embodiments of the invention are possible that do not include all features of the main claim. The main and dependent claims relate to advantageous embodiments and further developments of the invention. Brief description of the drawing

[0008] The invention is explained in more detail below with reference to one embodiment. The figures shown are: Fig. 1. A hydraulic circuit diagram of a slip-controlled, externally powered vehicle braking system; and Fig. 2 and Fig. 3 a hydraulic block according to the invention in perspective view looking at one side of the engine ( Fig. 2) and to an opposite side of the valve ( Fig. 3).

[0009] The hydraulic block is in Fig. 2 and Fig. 3 drawn transparently to show its bore. embodiment of the invention

[0010] Fig. Figure 1 shows a hydraulic circuit diagram of a slip-controlled, externally powered vehicle braking system 1 with two brake circuits. The vehicle braking system 1 has a manually operated tandem or dual-circuit master cylinder 2, to which two brake circuits are connected via a separating valve 3 each. Each brake circuit has one or more wheel brakes 4, in this embodiment two, which are connected to the separating valve 3 of the respective brake circuit via a pressure build-up valve 5 each. The wheel brakes 4 are connected to the master cylinder 2 via pressure release valves 6. Furthermore, the vehicle braking system 1 has a cylinder-piston unit 7, to which the wheel brakes 4 are connected via a service brake valve 8 in each brake circuit and via their pressure build-up valves 5. The cylinder-piston unit 7 can be actuated by an electric motor 9 via a helical gear.The isolating valves 3 and the pressure build-up valves 5 are open 2 / 2-way solenoid valves in their de-energized basic position, and the pressure reduction valves 6 and the service brake valves 8 are closed 2 / 2-way solenoid valves in their de-energized basic position.

[0011] Service braking is achieved by external force using the cylinder-piston unit 7. For service braking, the isolating valves 3 are closed, thus hydraulically disconnecting the master brake cylinder 2 from the vehicle's brake system 1. The service brake valves 8 are opened, and brake pressure is generated by the cylinder-piston unit 7. The master brake cylinder 2 serves as the setpoint transmitter for the brake pressure to be generated by the cylinder-piston unit 7. For slip control, wheel brake pressures in the wheel brakes 4 can be modulated individually for each wheel using the pressure build-up valves 5 and pressure reduction valves 6. Such slip control systems are well-known and will not be explained further here.

[0012] The vehicle brake system 1 has a master brake cylinder pressure sensor 10, which is connected to the master brake cylinder 2, and a brake circuit pressure sensor 11 in each brake circuit. Furthermore, two spring- or gas-pressurized hydraulic accumulators are connected via a simulator valve 12 as pedal travel simulators 13. During service braking, the master brake cylinder 2 displaces brake fluid into these accumulators when the master brake cylinder 2 is hydraulically disconnected from the vehicle brake system 1 by closing the isolating valves 3 and the vehicle brake system 1 is actuated by the cylinder-piston unit 7. The pedal travel simulators 13 enable the displacement of a piston of the master brake cylinder 2 with an increasing actuating force, as is customary, with increasing displacement.The simulator valve 12 is a 2 / 2-way solenoid valve that is closed in its de-energized basic position and is opened for service braking, thus connecting the master brake cylinder 2 with the two pedal travel simulators 13.

[0013] In the event of failure of the external power braking system, i.e., for example the electrically actuated cylinder-piston unit 7, the isolating valves 3 remain open and the simulator valve 12 remains closed, and the vehicle braking system 1 is actuated for an auxiliary braking by muscle power with the master brake cylinder 2.

[0014] The cylinder-piston unit 7 is connected to the pressure reduction valves 6 and the master brake cylinder 2 via a check valve 14, which allows flow towards the cylinder-piston unit 7, so that the cylinder-piston unit 7 can draw in brake fluid through the check valve 14 when its piston is returned to a home position.

[0015] All the hydraulic components of the vehicle brake system 1 described above, namely the master brake cylinder 2, the solenoid valves 3, 5, 6, 8, 12, the cylinder-piston unit 7, the pedal travel simulators 13, the pressure sensors 10, 11 and the check valve 14, are arranged in a hydraulic block 15, which is in Fig. 2 and Fig.Figure 3 is shown transparently to reveal its bore. The hydraulic block 15 is a cuboid metal part, for example, made of an aluminum alloy, although a non-metallic hydraulic block 15 is not excluded. It serves for the mechanical mounting and hydraulic connection of the hydraulic components of the vehicle brake system 1. In this view, the hydraulic block 15 is rectangular and flat; in the embodiment, the hydraulic block 15 is approximately 1 / 4 to 1 / 3 as thick as it is wide or high. It is designed for upright mounting in a motor vehicle, such that one transverse side 16 is at the top and another transverse side is at the bottom. By machining, the hydraulic block 16 is provided with receptacles for the hydraulic components of the vehicle brake system 1 and with connections for the wheel brakes 4. The receptacles and the connections are connected by lines, i.e., hydraulically connected, which are produced by drilling.The inlets, connections and lines are largely arranged Cartesianally, i.e. they run parallel or at right angles to each other and to the edges and surfaces of the hydraulic block 16.

[0016] The hydraulic block 15 has two connections 17' on its transverse side 16, which is located at the top in the intended installation position and is referred to here as the upper transverse side 16, for a pressureless brake fluid reservoir 17. The brake fluid reservoir 17 is of the type known from master brake cylinders and is designed to be mounted on the upper narrow side 16 of the hydraulic block 15.

[0017] At a distance from the upper transverse side 16, the hydraulic block 15 has four connections 4' for the wheel brakes 4, which are arranged side by side in a row on a flat side, here referred to as the motor side 18 of the hydraulic block 15. The connections 4', 17' are designed as cylindrical recesses into which the brake fluid reservoir 17 is simply inserted, whereas the wheel brake lines of the wheel brakes 4 are pressure-tightly connected to the connections 4', for example by screwing or crimping, particularly using the so-called self-clinching technique.

[0018] Following the series of connections 4' for the wheel brakes 4, the hydraulic block 15 has the master brake cylinder 2, which in the embodiment is designed as a bore with graduated diameters and circumferential grooves, which passes transversely, i.e. parallel to the transverse sides 16 from one longitudinal side 19 to an opposite longitudinal side 19 through the hydraulic block 15.

[0019] On one of the flat sides opposite the motor side 18, where the connections 4' for the wheel brakes 4 are located, and which is here referred to as valve side 20, the hydraulic block 15 has three rows, each with four receptacles for the solenoid valves of the vehicle brake system 1. In a first row, adjacent to the master brake cylinder 2, four receptacles 5' for the brake pressure build-up valves 5 are arranged side by side. In a space between the receptacles 5' for the pressure build-up valves 5, a receptacle 10' for the master brake cylinder pressure sensor 10 is arranged, and offset towards the master brake cylinder 2 are two receptacles 11' for the brake circuit pressure sensors 11. The three receptacles 10', 11' for the pressure sensors 10, 11 are arranged in a triangle.

[0020] In the second row, the hydraulic block 15 has four adjacent receptacles 6' for the pressure-reducing valves 6. This is followed by the third row with receptacles 3' for the isolating valves 3 and 8' for the service brake valves 8, the receptacles 3' for the isolating valves 3 being on the outside and the receptacles 8' for the service brake valves 8 on the inside. A further row contains a receptacle 12' for the simulator valve 12, which is located on a side facing away from the master brake cylinder 2, between a receptacle 3' for an isolating valve 3 and a receptacle 8' for a service brake valve 8. Two receptacles 13' for the pedal travel simulators 13 are mounted in a lower transverse side.The receptacles 3', 5', 6', 8', 12' for the solenoid valves and the receptacle 13' for the pedal travel simulators 13 are designed as cylindrical, graduated-diameter recesses in which the solenoid valves and the hydraulic accumulators are arranged and sealed pressure-tight by caulking. The use of two hydraulically parallel-connected pedal travel simulators 13 allows for a flatter hydraulic block 15.

[0021] Centrally located on the motor side 18 of the hydraulic block 15 is a cylindrical recess forming the cylinder 7' of the cylinder-piston unit 7. The two receptacles 8' for the service brake valves 8 and a receptacle 14' for the check valve 14, through which the cylinder-piston unit 7 draws in brake fluid when the piston returns to its resting position, open into its base.

[0022] Between the two mountings 13' for the pedal travel simulators 13, the hydraulic block 15 has a hole serving as a cable gland 23, which passes through the hydraulic block 15 from the motor side 18 to the valve side 20. The cable gland 23 is oval and narrower than it is tall, so that it occupies less space between the mountings 13' for the pedal travel simulators 13. The cable gland 23 serves to connect the electric motor 9, which is mounted on the cylinder 7' on the motor side 18 of the hydraulic block 15. The connection is made on the valve side 20, where the solenoid valves and pressure sensors are also connected, so that all electrical connections are located on the same side of the hydraulic block 15, in this embodiment on the valve side 20.

[0023] A transverse bore, serving as a simulator connection line 24, runs along the base of the receptacles 13' for the pedal position simulators 13 in the hydraulic block 15. Short branch lines 25 in the base of the receptacles 13' hydraulically connect the two simulators 13. One of the two branch lines 25 extends to the receptacle 12' for the simulator valve 12, thus connecting the pedal simulators 13 to the simulator valve 12. The simulator connection line 24 terminates on a longitudinal side of the hydraulic block 15 and is pressure-tightly sealed there, for example, by a pressed-in ball.

Claims

[1] Hydraulic block for a hydraulic unit of a hydraulic vehicle brake system, comprising a master brake cylinder (2) and another cylinder (7'), characterized by , that the further cylinder (7) is arranged centrally in a flat side (18) of the hydraulic block (15) and that the hydraulic block (15) has a line passage (23) on a side of the further cylinder (7') facing away from the master brake cylinder (2) in a longitudinal median plane of the hydraulic block (15) which passes from one to the other flat side (18, 20) of the hydraulic block (15), wherein the hydraulic block (15) has connections (4') for wheel brakes (4) in a flat side (18) of the hydraulic block (15) transverse to the master brake cylinder (2). [2] Hydraulic block according to claim 1, characterized by , that the cable entry (23) is narrower than it is high. [3] Hydraulic block according to claim 1, characterized by, that the hydraulic block (15) has a receptacle (13') for a pedal travel simulator (13) on both sides of the pipe penetration (23). [4] Hydraulic block according to claim 1, characterized by , that the hydraulic block (15) has a first row of receptacles (5') for valves (5) of the hydraulic vehicle brake system (1) and a receptacle (10') for a pressure sensor (10) in a center between the receptacles (5') of the valves (5) in the first row of the hydraulic block (15). [5] Hydraulic block according to claim 4, characterized by , that the hydraulic block (15) has two further receptacles (11) for pressure sensors (11) which are offset towards the master brake cylinder (2) and are in a triangle with the one receptacle (10)' for the one pressure sensor (10). [6] Hydraulic block according to claim 1, characterized by , that the hydraulic block (15) has a receptacle (14') for a valve (14) in a base of the further cylinder (7'). [7] Hydraulic block according to claim 3, characterized by , that the two receptacles (13') for the pedal travel simulators (13) are connected to each other and to a receptacle (12') for a simulator valve (12) by a simulator connection line (24), which runs transversely in the hydraulic block (15) at a base of the receptacles (13') for the pedal travel simulators (13) and has a pressure-tight sealed outlet on a longitudinal side of the hydraulic block (15).

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