DE10100315C1 - Pressure fluid accumulator for vehicle brake systems - Google Patents

Abstract

The invention relates to a pressure medium reservoir for brake systems of vehicles. The pressure medium reservoir is connected to a hydraulic module (23). The pressure medium accumulator comprises a accumulator housing (30) which is divided into two separate chambers by means of a separating element (31) and is sealed with a closure cover (32) and by a base element (37). The separating element (31) is enclosed by a guide ring (36) which slides along the inner wall of the storage housing (30). The storage housing (30) and the hydraulic module (23) are positively connected to one another by means of a connecting element (41, 48).

Description

Technical field

Brake systems on vehicles, be they passenger cars, commercial vehicles or rails vehicles are designed so that on the one hand no boiling point of the brake fluid down moisture entering the brake system and the brake high, sudden peak pressures easily coped with. Is next to it ensures that the vehicle can be stopped with muscle power Parts of the brake system fail. For damping the pulsation of pressure vibrations in the Line system of the brake system, pressure accumulators are used, which the pulsation in the Damp brake system and pressure-tight on the hydraulic unit of the brake system are taken.

State of the art

DE 198 33 410 A1 relates to a hydraulic control unit for motor vehicle Brake systems. It is under pressure and can be controlled by an electronic control unit Standing hydraulic fluid supplying pump provided that the hydraulic fluid for little least provides a braking device coupled to a vehicle wheel. The pump is assigned a first reservoir for unpressurized hydraulic fluid on the input side, during the On the output side, pump in a second reservoir for pressurized hydraulic fluid is ordered. The pump, the first and the second reservoir are in a common one Housing integrated as an electro-hydraulic unit.

DE 199 06 800 A1 relates to a pressure storage unit for brake systems. An on a bellows arranged in a storage housing is enclosed by a guide ring, which is supported on the inner walls of the storage housing. The storage case is with  provided with a threaded neck with which it ver in an upper part of the hydraulic unit is screwed. This will cause the pressure to twist during the joining process telspeicherehäuses required relative to the hydraulic module, which is space-related Can cause difficulties; on the other hand, a tool is only difficult rigen so that the tightening torque on the thread is not exactly defined can be brought.

EP 0 980 981 A1 shows a pressure medium storage device, which is particularly suitable for slip-controlled ones Automotive brake systems are used. This includes one with a pressure medium connection provided housing and a valve element, which opens the pressure medium connection or closes. In the pressure medium reservoir, a spring element is provided, which is on the forehead surface of a bellows is attached. This works with the pressure medium connection facing valve element together. There is a movably arranged, min at least two chambers in the body separating the pressure medium from each other men, which is designed as a movable bellows enclosing a first chamber is, the chamber enclosed by the bellows is filled with a gas. Between the end face of the bellows and the end face of the housing is a stop see the closing stroke of the valve element in the direction of the pressure medium connection limited, wherein the valve element relative to the spring element is relatively movable is arranged.

DE 198 05 843 A1 relates to a hydraulic unit for slip-controlled brake systems vehicles. This solution shows a low designed as a piston accumulator pressure accumulator, the housing of which consists of a sheet metal part, in which the same also before pistons pressed from a thin sheet metal part are sealed by O-rings and is guided in the housing. The circumferential collar of the housing lies just like the piston ground on the end face of a relatively flat storage hole and is in the water attached by means of a caulking tool in the receiving body. Another out The management form of DE 198 05 843 A1 is a cylindrical projection in the memory take the mounting hole in an annular groove for sealing the storage case ses an O-ring.

Presentation of the invention

The object of the present invention is to provide an inexpensive assembly a pressure bellows containing metal bellows with pulsation damping to enable a hydraulic module.

With the solution proposed according to the invention, assembly is simple and quick pressing of the components to be joined using a connecting element mentes in the form of a self-clinching bolt. The connecting element, which on both Housing of the pressure medium reservoir form-fitting as well as on the hydraulic unit thanks to its rigid inflexible wall, it acts as a pulsation damping connection. The fact that the housing of the pressure accumulator is positive connected to the hydraulic module provides an additional, advantageous security aspect because there is now a separation and improper handling of the pressure memory, d. H. is prevented with a safety-relevant part of the braking system.  

The seal between the pressure accumulator and the hydraulic module is made using a metallic one Component, so that no elastomers are required as sealing materials. Make elastomers after a certain lifespan due to embrittlement symptoms the original sealing properties are available. Sealing with pure metallic materials are not subject to signs of aging.

With the solution proposed according to the invention, a simple and quick can Assemble the hydraulic module and pressure accumulator by pressing. One before assembled pressure accumulator assembly, consisting of metal bellows with attached on both sides brought closure or lid and plastic guide ring can also be Manufacture press-in. After installation, the storage housing can be filled with gas be pressurized in a chamber formed in the storage housing.

The bolt-like connection element between the storage case and Hy draulic module can be provided with a simple through hole; furthermore is an embodiment of this component with an inflow / outflow system possible, so that there is a separation of the incoming from the emerging brake fluid flow. In the last-mentioned embodiment variant can a dop on the bolt-like connecting element pelte connection to the hydraulic module can be provided.

The plastic deformation of the material of the accumulator housing and hydraulic module by pressing enables a positive connection of the components to each other by a positive connection that is permanent and a loosening of the connection between si safety-related pressure accumulator housing and hydraulic module safely prevented.

drawing

The invention is described in more detail below with reference to the drawing:

It shows:

Fig. 1 shows the basic construction of a brake system of motor vehicles,

Fig. 2, 2.1 and 2.2 a first embodiment of the connecting element between the pressure accumulator and hydraulic unit and

Fig. 3, 3.1 a further embodiment of the connecting element between the pressure accumulator and hydraulic unit with separate supply / discharge hole.

variants

Fig. 1 shows the basic structure of a brake system of motor vehicles, the essential components we reproduce in schematic form.

The braking system of a vehicle essentially consists of two modules, a control module 10 and a hydraulic module 23 , which are shown in the illustration according to FIG. 1 in its essential components. A piston rod 4 , which is connected to a movable piston 5 , is displaced within a master brake cylinder 3 via a brake pedal 2 . A reservoir 6 ensures that the master brake cylinder is supplied with a sufficient fluid supply. The Hauptbremszy cylinder 3 is followed by two 2/2-way valves 7 and 8 , which can be designed, for example, as magnetic valves, which assume a locked position and a release position and which are acted upon by a spring element. The first 2/2-way valve 7 is connected to a piston / cylinder arrangement 9 .

The control unit 10 and the hydraulic module 23 mentioned are connected to one another via a hydraulic line from the second 2/2-way valve 8 .

A pressure medium accumulator is provided in the upper area of the hydraulic module 23 , of which only the accumulator housing 30 is shown here. Via a schematically illustrated connecting element 41 , the pressure medium reservoir and the hydraulic module 23 are connected to one another in a pressure-tight manner. In brake systems, metallic bellows are generally accommodated in pressure medium accumulators, which form a closed chamber pressurized with a pressurized gas within the storage housing 30 . About the connecting element 41 occur in the pump 15 pump pulsations in the pressure medium reservoir 11 , which are damped in this, so that in Hy hyululmodul 23 , or in its piping system can build insignificantly low pressure vibrations gene.

The hydraulic module 23 of the brake system according to FIG. 1 is assigned a reservoir 12 , which is connected via a line 19 with a solenoid valve 20 designed as a multi-way valve. A pressure relief valve 13 is arranged between a line extending from the reservoir 11 to a valve arrangement and a line extending from the reservoir 12 to a pump 15 .

By means of a pump 15 , the brake fluid present on the inlet side, ie on the inlet side 16 of the pump, is brought to a higher pressure which is present on the outlet side 17 of the pump 15 . On the output side, a check valve 18 is assigned to the pump 15 , via which the brake fluid under high pressure is applied to the solenoid valve group 20 formed as a multi-way valve. The solenoid valve group 20 consists of the inlet valve 14 a and the outlet valve 14 b. About the multi-way valve 20 is a Trennzy cylinder 21 corresponding to the switching position of the multi-way valve 20 with the high pressure in hydraulic likmodul 23 on the output side of the pump 15 pressurized, so that the corresponding wheel brake cylinder assembly 22 can be pressurized via the trend cylinder 21 .

Should parts of the hydraulic module 23 fail, the line extending from the first 2/2-way valve 8 to the separating cylinder 21 of the hydraulic module 23 ensures that the wheel brake cylinder arrangement 22 on the vehicle can be actuated by the pedal force 2 acting on the master brake cylinder 3 .

From FIGS. 2, 2.1, and 2.2 is a first embodiment of a brake system Verbindungsele mentes between pressure accumulator and hydraulic unit of a vehicle more apparent.

30 Fig. 2 shows a memory housing of the accumulator 11 for a brake system of vehicles, in which a separating element 31 acting as a metallic bellows is inserted. The metallic bellows is attached with an end face to a lid-shaped closure element 32 . A bore 34 is formed in the lid-shaped closure element 32 and can be closed by a spherically configured closure element 33 . Via the bore 34 in the closure cover 32 , the interior of the metallic bellows 31 functioning as a separating element is pressurized by gas filling. In the configuration according to FIG. 2, the closure cover 32 is embedded in a circumferential groove on the storage housing 30 with laterally projecting surfaces. The Verschraubdec angle 32 is also associated with an O-ring 35 formed sealing element. Un at the underside of the separating element 31 acts as metallic bellows 31 is fixed a further lid 37, the chamber formed as the bottom of by the bellows 31 and the cap 32 is to be considered within the storage housing 30th Between the bottom 37 and the bellows side wall 31 is a metallic bellows 31 surrounding guide ring 36 is arranged, which is displaceable on the inner walls of the storage housing 30 of the pressure medium reservoir configured according to the invention. A sealing element 38 is provided on the underside of the cover element 37 .

In the bottom of the storage housing 30 is a part of a bolt-shaped Ver connecting element 41 is pressed, which is pressed with its area opposite a support shoulder in the upper region of the hydraulic module 23 or 39 . The bolt-shaped connecting element 41 is penetrated in the center by a bore which serves both as an inflow line and as an outflow line for the brake fluid of the hydraulic module 23 , the pulsations of which are to be damped in the pressure medium storage housing 30 . Through the actable in both directions through bore 42 of the bolt-shaped connecting element 41 , the brake fluid enters the chamber delimited by the inner wall of the storage housing 30 and the outer wall of the bellows 31 , the interior of which is pressurized.

From the view in Fig. 2.1, the bolt-shaped connection 39 is configured between memory element housing 30 and top of the hydraulic module 23, shown in more detail.

An annular support shoulder 43 is formed approximately in the center of the outer wall of the bolt-shaped connecting element 41 . From the view in Fig. 2.1 shows that the support shoulder 43 on both sides be of annular configuration in the wall of the bolt-shaped connecting element 41 annular grooves 44 is limited. In the pressed-in state of the connecting element 41 both in the storage housing 30 and in the housing of the hydraulic module 23 , plastically deformed material 45 or 46 enters the annular grooves 44 provided in the circumferential direction on the outer wall of the bolt-shaped connecting element 41 and connects both the bottom of the storage housing 30 and also the top of the hydraulic module 23 with both sides of the bolt-shaped connecting element 41 provided with a through bore 42 . Due to the resulting between the top 39 , 23 of the hydraulic module and the underside of the storage housing 30 , the height of the support shoulder 43 corresponding gap, access to loosen the positive connection is not possible, so that a separation of the pulsation damping of pressure Vibration-serving pressure medium accumulator from the hydraulic module 23 or its improper, unskilled replacement is prevented.

The variant of the connecting element 41 between the accumulator housing 30 and the hydraulic module 23 according to the representations in FIGS. 2 and 2.1 allows, in an advantageous manner, to design a accumulator housing 30 from a soft metal material such as aluminum as an extruded part. This is the production of a press connection between the storage housing material and the annular groove 44 of the bolt-shaped connecting element 41 favorable. A preassembled unit consisting of the components 32, 31 and 35, 36, 37, 38 of the bolt-shaped connecting element configured to be inserted 41 in the bottom of the storage case 30 in the cup-shaped storage case 30 by pressing the upper part. Subsequently, the existing assembly from the pre-assembled pressure medium accumulator and the pressed-in connection element 41 is pressed into a hydraulic module 23 so that the annular grooves 44 formed on the outer wall of the bolt-shaped connection element 41 can be filled with the plastically deformed material 46 of the hydraulic module 23 , This ensures a positive connection via the bolt-shaped connecting element 41 both on its top to the bottom of the storage housing 30 and on the bottom with the top of the hydraulic module 23 .

Depending on the thickness of the wall 47 , the annular grooves 44 , which limit the support shoulder 43 in the circumferential direction according to the illustration in FIG. 2.1, can be implemented in different depths.

A further embodiment variant of the connecting element between a pressure medium reservoir and a Hydraulikmo module of a brake system with separate inflow / outflow bores is shown in more detail in the illustrations according to FIGS. 3 and 3.1.

Fig. 3 shows an essentially identical to the representation of FIG. 2 variant of a preassembled pressure medium storage element, consisting of memory housing 30 and accommodated in this metallic bellows 31 , sealing cover 32 together with gas filling openings, sealing element 36 , bottom part 37 , guide ring 36 and on the bottom part 37 received sealing element 38 .

In contrast to the illustration according to FIG. 2, the connecting element 48 configured in the form of a bolt has a separate bore system 50 , 49 .

At the end of the stroke of the metal bellows 31 , the sealing element 38 separates the storage chamber from the bores 49 and 50 . The holes 49 and 50 are connected to each other via a gap S ( Fig. 2.2).

In the hydraulic module 23 , in which the lower part of the bolt-shaped Ver connecting element 48 is embedded according to FIG. 3, the inflow bore 49 and the outflow bore 50 are spatially separated from one another. The trained in Fig. 3 in the hydraulic module 23 Zuströmungsbohrung 49 opens into a through bore in the bolt-shaped configured connection element 48, while provided in the connecting element 48 discharge bores 50 communicate with a downstream hole provided 50 of the hydraulic module 23 in connection, the space from the inlet bore 49 in the Hydraulic module 23 is separated.

From the view in Fig. 3.1, the bolt-shaped configured connection 3 goes element 48 as shown in Fig. More apparent. Via the bore 49 in the hydraulic module 23 , the brake fluid enters the through bore of the bolt-shaped configu rated connecting element 48 . Through the through hole, the brake fluid flows in the direction of the sealing element 38 arranged on the bottom surface 37 of the bellows 31 and, when the pressure is correspondingly present, this opens, so that it is between the outer side of the metallic bellows 31 , which is pressurized from the inside, and the inside of the storage housing 30 can dampen pressure pulsations in the brake fluid.

On the outflow side, the brake fluid flows out of the interior of the storage housing 30 via the outflow bores 50 provided in parallel in the bolt-shaped connecting element 48 . Are associated via openings 53, each of the two verlaufenen in the bolt-shaped connecting element 48 configured bore 50, the outgoing brake fluid enters the hydraulic module 23 in the bore 50th

The spatial separation of the two fluid streams is maintained by partition walls 51 , which are formed between the two outflow bores 50 and the through bore 49 in the bolt-shaped connecting element. Analogous to the representation of FIG. 2.1 is 48 formed the support shoulder 43 of the connecting element as a thickening in the wall 47 of the connecting element 48. On both sides of the circumferential support shoulder 44 , annular incisions, ie annular grooves 44 are provided, which are filled by the material 45 of the storage housing base 30 or by the material of the Hydraulikmo module 23 . On the underside, ie the area of the bolt-shaped connecting element 48 accommodated in the hydraulic module 23 , there are two annular grooves 44 . The first annular groove 44 lies below the circumferential support shoulder 43 , while the further annular groove 44 lies in the lower part of the connecting element 48 below the outflow bore 50 in the hydraulic module 23 . Since both annular grooves 44, circumferential surface on the order of the bolt-shaped configured connection element 48 mentes by the plastically deformed material 46 during pressing of the lower part of the Verbindungsele be filled 48 with the hydraulic module 23 of its material, is a separation of the inflow bore system 49 from the outflow hole system 50 guaranteed by the arrangement proposed according to the invention of the positive locking connection points 44 , 46 and 44 , 52 at two positions.

Instead of the previously used elastomeric masses at the critical joints between the connecting elements 41 and 48 and the bottom of the pressure accumulator housing 30 and the upper part of the hydraulic module 23 , the sealing effect is now by plastic deformation of the relatively soft material aluminum when pressed in from the bottom of the accumulator housing 30 or Pressing of the connecting element 48 into the upper part of the hydraulic module 23 is achieved. Since this form-fitting connection cannot be canceled again without destruction, there is a permanent connection that cannot be accessed by improper access or handling. Improper replacement is prohibited in the case of a safety-critical component such as a brake system of a motor vehicle.

The method also disclosed according to the invention relates to a joining method of a pressure medium reservoir with a hydraulic module. First, the storage housing 30 , which preferably consists of a soft metallic material such as aluminum, is produced by extrusion. In the bottom of the memory housing 30 , the upper loading area of the bolt-shaped connecting element 41 or 48 is pressed. Then the assembly consisting of metallic bellows 31 , sealing cover 32 together with bore 34 and closing element 33 , sealing element 35 , base part 36 together with the guide ring, which is displaceable on the housing interior, is mounted on the storage housing 30 . This preassembled assembly can be accommodated in the storage housing 30 , for example by welding or by a shaping process.

Subsequently, this assembly consisting of storage housing 30 together with built-in parts and pressed-in connecting element 41 or 48 is pressed in by pressing it onto one or two points producing a positive connection with the upper side on the hydraulic module 23 . After this assembly, the interior of the metallic bellows 31 is filled with gas via the bore 34 provided in the closure cover 32 , which is closed by the closure element 33 after filling.

LIST OF REFERENCE NUMBERS

1

braking system

2

pedal

3

Master Cylinder

4

piston rod

5

piston

6

reservoir

7

first 2/2-way valve

8th

second 2/2-way valve

9

Piston / cylinder assembly

10

control unit

11

Storage

12

reservoir

13

Pressure relief valve

14

valve assembly

15

high pressure pump

16

input side

17

output side

18

check valve

19

management

20

Multi-way valve

21

separating cylinder

22

wheel brake cylinder

23

hydraulic unit

30

storage Enclosures

31

separating element

32

cap

33

closing

34

drilling

35

sealing ring

36

guide ring

37

cover

38

sealing plate

39

hydraulic unit

40

drilling

41

connecting element

42

Through Hole

43

support shoulder

44

ring groove

45

Material storage enclosure

30

46

Materials hydraulic unit

23

47

wall

48

Connection element with separate inflow / outflow bores

49

inflow bore

50

outflow bore

51

partition wall

52

further connection point

53

opening

Claims (10)

1. Pressure fluid reservoir for brake systems of vehicles, the Druckmittelspei cher ( 11 ) with a hydraulic module ( 23 ) of the brake system is connected and comprises a storage housing ( 30 ) which is divided into two separate chambers by means of a separating element ( 31 ), which Storage housing ( 30 ) with a sealing cover ( 32 ) and sealed by a closing element ( 33 ), the separating element ( 31 ) being enclosed by a guide ring ( 36 ) and the storage housing ( 30 ) and the hydraulic module ( 23 ) by means of a connecting element (41, 48) are positively connected with each other, characterized in that connecting element on the Ver (41, 48) both in the joining region of the accumulator housing (30) and mentes on the outer wall of the Verbindungsele in the joining region of the hydraulic unit (23) (41, 48 ) annular groove-shaped recesses ( 44 ) are each formed to form a press connection. 2. Pressure fluid accumulator according to claim 1, characterized in that the connec tion element ( 41 , 48 ) on its outer wall with a circumferential support school ter ( 43 ) is provided. 3. Pressure medium accumulator according to claim 1, characterized in that the annular outer recesses ( 44 ) on the outer wall of the connecting element ( 41 , 48 ) are provided as annular grooves. 4. Pressure fluid accumulator according to claim 1, characterized in that the connec tion element ( 41 , 48 ) has a through hole ( 42 ) for inflow and outflow of the brake fluid. 5. Pressure fluid accumulator according to claim 2, characterized in that the annular grooves ( 44 ) in the axial direction of the connecting element ( 41 , 48 ) seen on both sides of the support shoulder ( 43 ) are formed. 6. Pressure fluid accumulator according to claim 1, characterized in that the connec tion element ( 41 , 48 ) is provided with separate bores ( 42 , 49 , 50 ) for supplying and supplying the brake fluid from the pressure fluid accumulator. 7. Pressure fluid accumulator according to claim 6, characterized in that in the hydraulic module ( 23 ) a feed bore ( 49 ) and an outflow bore ( 50 ) through in the annular grooves ( 44 ) on the connecting element ( 48 ) entering housing material ( 52 , 46 ) are separated. 8. Pressure fluid accumulator according to claim 7, characterized in that on the part in the hydraulic likmodul ( 23 ) fixed part of the connecting element ( 41 , 48 ) positive Ver Ver connection points ( 44 , 46 ; 44 , 52 ) seal the downstream line side ( 50 , 53 ). 9. Pressure fluid accumulator according to claim 1, characterized in that the Trennele element ( 31 ) in the accumulator housing ( 30 ) is designed as a metallic bellows, piston or membrane. 10. Method for joining a pressure medium reservoir with a hydraulic module ( 23 ), a brake system for vehicles with the following method steps:

• - The pressing of a connecting element ( 41 , 48 ) with annular groove-shaped recesses ( 44 ) on both sides of a support shoulder ( 43 ) in a storage housing ( 30 ),
• - The insertion of a pre-assembled assembly of sealing elements ( 32 , 33 , 35 ), separating element ( 31 ) and guide ring ( 36 ) in the housing ( 30 ),
• - The pressing of the connecting element / housing assembly ( 30 ) in a hy draulic module ( 23 ) of a brake system.