DE102007059374A1 - Vehicle brake assembly has compression unit for producing hydraulic brake pressure, where compression unit is hydraulically connected with brakes - Google Patents

Abstract

A vehicle brake system comprises a pressure generating device for generating a hydraulic brake pressure, wheel brakes, which are hydraulically connected to the pressure generating device, a hydraulic unit (30), which is hydraulically incorporated between the pressure generating device and the wheel brakes and via which the brake pressure at the individual wheel brakes is individually adjustable, and a pyrotechnic pressure generator (40). In this case, a pyrotechnic pressure generator (40) for two brake circuits is arranged directly on the hydraulic unit (30), which has a pyrotechnic piston which can be acted upon and, when activated, generates a brake pressure for full braking. By using only one pressure generator for both brake circuits directly on the hydraulic unit results in a compact and easy to maintain design, which avoids contamination of the pressure medium with combustion gases.

Description

The The invention relates to a vehicle brake system comprising a Pressure generating device for generating a hydraulic brake pressure, Wheel brakes, which are hydraulically connected to the pressure generating device are, and a hydraulic unit, the hydraulically between the pressure generator and the wheel brakes is incorporated and about the brake pressure is individually adjustable at the individual wheel brakes.

such Vehicle brake systems are well known in the art. about the hydraulic unit, which a variety of individually controllable Valves may, by modulation of the predetermined by the pressure generating means Brake pressure the functionality of an anti-lock braking system and optionally other functionalities such as representing an electronic stability program become.

in the Case of emergency braking is about the vehicle brake system in a very short time a full brake pressure can be built up, to achieve a maximum delay.

To allow for a vehicle brake system of the type mentioned an extremely fast pressure build-up, is from the DE 30 19 364 C2 known to provide a pyrotechnic pressure generator which is triggered in the event of emergency braking. The Indian DE 30 19 364 C2 proposed pressure generator comprises a pyrotechnic propellant, is displaced by the ignition after a pressure medium from a pressure fluid reservoir and fed via a line in the hydraulic unit. However, there is the risk that after ignition combustion gases are fed into the vehicle brake system, so that their operability is impaired by triggering the pyrotechnic propellant under certain circumstances.

In the WO 2006/061279 A1 It is proposed to integrate a pyrotechnic pressure generator in the hydraulic unit for each brake circuit. The pressure generator in this case comprises a piston which separates a pyrotechnic chamber from a hydraulic pressure chamber in order to avoid contact of the pressure medium with the combustion gases after triggering the pyrotechnic propellant, since the vehicle brake system should remain operational after triggering the pyrotechnic pressure generator. However, this results in vehicle braking systems with two brake circuits a very bulky hydraulic unit block. Although a spent pyrotechnic propellant can be easily replaced. However, if damage occurs to the piston or to the piston guide, it may be necessary to replace the entire hydraulic unit block.

Of the Invention is based on the object, a vehicle brake system to provide with a pyrotechnic pressure generator, which the avoids the above-mentioned disadvantages. In particular, the aims Invention to a compact, maintenance-friendly configuration, in the case of a contamination of the pressure medium with combustion gases is avoided.

These Task is achieved by a vehicle brake system according to claim 1 solved. The vehicle brake system according to the invention is characterized in particular by the fact that a pyrotechnic Pressure generator for two brake circuits on the hydraulic unit is arranged, which is a pyrotechnic loadable piston has and when activated a brake pressure for a Full braking generated.

By the use of only one pressure generator for both Brake circuits directly on the hydraulic unit results in a compact and maintenance-friendly construction, which nevertheless a contamination of the pressure medium with combustion gases avoids.

Further, advantageous embodiments of the invention are in the claims specified.

Especially The pressure generator can be executed as a separate unit be releasably attached to the hydraulic unit. This allows a multi-level change of the components after ignition. If after a trip no further damage to the pressure generator occurred are, only the propellant of the same is exchanged. A Disassembly of the pressure generator is not required in this case. Otherwise, the entire pressure generator is replaced while the Hydraulic unit can be used.

According to an advantageous embodiment, a vent to the outside environment is provided between a hydraulic pressure chamber and a pyrotechnic chamber of the pressure generator, which are separated by the piston. This has the advantage that combustion gases from the pyrotechnic chamber can not pass the piston into the hydraulic pressure chamber, but escape much more into the outside environment. As a result, the risk of contamination of the pressure medium is reduced with combustion gases, thus further improving the ease of maintenance. Incidentally, this is also independent of the on Regulation of the pressure generator directly on the hydraulic unit, the releasable coupling of the pressure generator or the number of pressure generators on the hydraulic unit advantage.

According to one Another advantageous embodiment of the piston is after a Triggering in its disengaged end position automatically blocked. This avoids a reduction in braking performance immediately after tripping and ensures unrestricted Continued operation of the vehicle brake system after completion of full braking.

following the invention will be described with reference to embodiments shown in the drawings explained in more detail. The drawing shows in:

1 a schematic representation of an embodiment of a vehicle brake system according to the invention,

2 a schematic representation of a pressure generator to a hydraulic unit according to the invention,

3 a schematic representation of a first embodiment of a pressure generator with housing-side seals in rest position,

4 a schematic representation of the pressure generator according to the first embodiment in the tripped state,

5 a schematic representation of a second embodiment of a pressure generator with piston-side seals in rest position,

6 a schematic representation of the pressure generator according to the second embodiment in the tripped state,

7 a schematic representation of a third embodiment of a pressure generator with housing-side seals and check valves in the rest position,

8th a schematic representation of the pressure generator according to the third embodiment in the tripped state,

9 a schematic representation of a fourth embodiment of a pressure generator with piston-side seals and check valves in the rest position,

10 a schematic representation of the pressure generator according to the fourth embodiment in the tripped state,

11 a sectional view of a check valve in the installed state,

12 a schematic representation of a fifth embodiment of a pressure generator with housing-side seals and floating piston in rest position,

13 a schematic representation of the pressure generator according to the fifth embodiment in the tripped state,

14 a schematic representation of a sixth embodiment of a

pressure generator with piston-side seals and floating piston in rest position,

15 a schematic representation of the pressure generator according to the sixth embodiment in the tripped state

16 a schematic representation of a seventh embodiment of a pressure generator with floating piston in rest position,

17 a schematic representation of the pressure generator according to the seventh embodiment in the tripped state,

18 a first variant for fixing the pressure piston a) in the starting position and b) in the triggered end position, and in

19 a second variant for fixing the pressure piston a) in the starting position and b) in the triggered end position.

The exemplary embodiments explained below relate to a brake system for a motor vehicle, which includes a pressure-generating device 10 for generating a hydraulic brake pressure. About the pressure generating device 10 is dependent on the operation of a brake pedal 11 generated by a driver, a brake pressure on the wheel brakes 20 the individual vehicle wheels VL, HR, VR and HL is brought into effect. To assist the driver-side brake actuation includes the pressure generating device 10 furthermore a brake booster 12 , the master cylinder 13 The brake system has two separate brake circuits connected to separate chambers of the master brake cylinder 13 are connected. The vehicle wheel VL at the front left and the vehicle wheel HR at the rear right are supplied with brake pressure via a first brake circuit, the vehicle wheel VR at the front right and the vehicle wheel HL at the rear left via a second brake circuit.

Between the pressure generating device 10 and the wheel brakes 20 is a hydraulic power unit 30 hydraulically interposed. About the hydraulic unit 30 can the brake pressure on the wheel brakes 20 the individual vehicle wheels are set individually. As a result, for example, the functionality of an anti-lock braking system or an electronic stability program can be realized. The hydraulic unit 30 has per brake circuit to a controllable ASR valve ASR1 or ASR2, which is open during a normal operation of the vehicle brake system without control intervention. Downstream of the ASR valve, the respective brake circuit branches to controllable intake valves EV1 and EV2 or EV3 and EV4 of the individual wheel brakes 20 , which are also open in a normal brake application. The wheel brakes 20 a brake circuit are connected via a respective controllable, normally closed exhaust valve AV1 and AV2 or AV3 and AV4 with a return line, which via a switching valve SV1 or SV2 per brake circuit with the respective pressure line 14 respectively. 15 of the master cylinder 13 connected is. Between the input side of the inlet valves and the outlet side of the outlet valves, each brake circuit is a return pump 31 hydraulically integrated. In addition, each brake circuit, a pressure accumulator 32 between the outlet valves and the inlet side of the return pump 31 be arranged.

Furthermore, the vehicle brake system comprises a pyrotechnic pressure generator 40 , This is directly on the hydraulic unit 30 arranged and operatively connected to both brake circuits. As in the 3 and 4 shown by a first embodiment, the pressure generator comprises 40 an outer casing 41 with a cylindrical housing inner wall 42 in which one by a pyrotechnic propellant 43 acted upon piston 44 is slidably mounted. The piston 44 separates a hydraulic pressure chamber 45 from a pyrotechnic chamber 46 , The latter stands with the pyrotechnic propellant 43 in connection. Upon activation of the pressure generator 40 That is, a triggering of the pyrotechnic propellant 43 becomes the piston 44 by the gas pressure in the direction of the hydraulic pressure chamber 45 moved so that in the hydraulic pressure chamber 45 located pressure fluid or brake fluid in the hydraulic unit 30 is fed. The propellant 43 , the pyrotechnic chamber 46 and the hydraulic chamber 45 are matched to one another such that when activated always a sufficient brake pressure for full braking is provided, in which all wheel brakes 20 ensure maximum delay in every conceivable situation. The pressure level is below the critical pressure for the components of the brake systems. The anti-lock braking system remains active.

As 2 shows is the pressure generator 40 designed as a separate unit, the detachable on the hydraulic unit 30 attached, for example, is screwed. After a release of the propellant 43 this is replaced by a new propellant. If the triggering causes damage to the pressure generator 40 , this can also be exchanged if necessary. The hydraulic unit 30 this is always unimpaired.

The pyrotechnically generated hydraulic brake pressure of the pressure generator 40 is via channels 33 and 34 in the hydraulic unit 30 introduced, which downstream of the ASR valves ASR1 and ASR2 the brake circuits in to the wheel brakes 20 leading channels 35 respectively. 36 lead. As a result, throttle losses are switched off at the ASR valves.

In the illustrated embodiment according to 1 the junction is located in front of the inlet valves EV1-4 of the individual wheel brakes 20 , However, it is also possible to further avoid flow losses at the intake valves EV1-4, the hydraulic brake pressure of the pressure generator 40 downstream of the wheel brakes 20 to supply associated intake valves EV1 and EV2 or EV3 and EV4.

If a full braking is triggered by a control unit, not shown, the valves of the hydraulic unit 30 as in 1 shown switched. In particular, the ASR valves ASR1 and ASR2 of the two brake circuits are shut off in order to prevent overflow of the pressure medium into the expansion tank 16 of the master cylinder 13 to avoid. Alternatively or additionally, additional, not shown here shut-off valves in the pressure lines 14 and 15 be installed, which are normally open, in the case of a pyrotechnic full braking, however, be closed.

The exhaust valves AV1-4 on the wheel brakes 20 are closed during a full braking, while the inlet valves EV1-4 depending on the mouth of the channels 33 and 34 either be kept open as in 1 is shown for an entrance in front of the intake valves EV1-4, or closed, as long as the confluence is downstream of the intake valves EV1-4.

Furthermore, the piston 44 blocked after actuation in its disengaged end position, to push back the piston 44 to avoid the pyrotechnic pressure and thus a reduction in braking power immediately after a trip. After completion of full braking, the piston remains 44 in this position. The valves of the hydraulic unit 30 will be switched back to their normal operating position. The Brake system is then fully functional again with possibly slightly changed pedal feel, apart from the possibility of pyrotechnic triggering.

following be different embodiments of the pressure generator explained in more detail.

The in the 3 and 4 illustrated pressure generator 40 has a common pressure chamber 45 for both brake circuits, which via the outlet openings 47 and 48 are connected. The outlet openings 47 and 48 are located in the outer circumference of the housing inner wall 42 and be through the piston 44 opened and locked. In the in 3 shown rest position are the two brake circuits through the piston 44 separated from each other, this purpose the outlet opening 48 the second brake circuit shuts off. At a release of the pyrotechnic propellant 43 be during a movement of the piston 44 both brake circuits hydraulically with the pressure chamber 45 connected. In the illustrated embodiment, the piston 44 For this purpose, a radial opening 49 on that leading to the outlet opening 48 passes. In the in 4 illustrated disengaged position of the piston 44 on the other hand are the outlet openings 47 and 48 through the piston 44 locked, therefore both brake circuits separated, so that the vehicle brake system after completion of full braking with pyrotechnic release in normal operation with independent brake circuits can continue to be used.

As 4 further shows, is the piston 44 in its disengaged end position by a spring 50 blocked. The feather 50 is between the piston 44 and the leading housing inner wall 42 arranged and in the in 3 shown initial position held biased in the radial direction. In the illustrated embodiment, the spring 50 through the radial outer wall of the piston 44 in a wall recess 51 the housing inner wall 42 held. In the in 4 shown disengaged end position jumps the spring 50 in front of the piston 44 to prevent it from being pushed back. The feather 50 supports itself in the wall recess 51 and at a recess or at an axial end portion of the piston 44 from. As a result, a reduction of the brake pressure immediately after the release of the pyrotechnic pressure generator 40 avoided and the continued operation of the vehicle brake system guaranteed.

The piston 44 is both opposite the hydraulic pressure chamber 45 as well as towards the pyrotechnic chamber 46 sealed. Between these seals a communicating with the outside environment vent is arranged.

In the in the 3 and 4 shown first embodiment are suitable seals for this purpose 52 to 56 in recesses of the outer housing 41 arranged. These seal against the outer circumference of the piston 44 from. Two pairs of seals each 52 and 53 such as 54 and 55 seal the radial opening 49 of the piston 44 in the in 3 illustrated starting position and in the in 4 shown disengaged position axially against leakage of pressure medium or brake fluid. Furthermore, a seal 56 provided which the overflow of combustion gases from the pyrotechnic chamber 46 in the hydraulic pressure chamber 45 through the between the outer circumference of the piston 44 and the housing inner wall 42 should prevent formed gap. A certain leakage over the seal 56 However, it can never be completely ruled out. For this reason, between the latter seal 56 and the other seals 52 to 55 in the outer casing 41 a vent channel 57 formed to the outside, which in between the piston 44 and the housing inner wall 42 formed gap opens. Combustion gases, which the seal 56 overcome, so escape without pressure into the environment. This reliably prevents combustion gases from entering the brake system.

Furthermore, the outer housing 41 one through a stopper 60 lockable opening 59 on, over which the hydraulic pressure chamber 45 filled and can be vented if necessary.

The 5 and 6 show a second embodiment of the pressure generator 40 ' , This is functionally designed according to the first embodiment, but the seals 52 ' to 56 ' now on the piston 44 ' arranged while the housing inner wall 42 ' is free of Dichtungsausnehmungen. It seal two seals 52 ' and 53 ' the outlet opening 48 ' in the starting position as well as two further seals 54 ' and 55 ' the outlet opening 48 ' in the disengaged position of the piston 44 ' in the gap between the outer circumference of the piston 44 ' and the housing inner wall 42 ' from.

The spring 50 ' receiving wall recess 51 ' remains on the outer casing 41 ' , The feather 50 ' engages in the disengaged end position according to 6 in a radial wall recess 58 ' of the piston 44 ' to block this.

The 7 and 8th show a third embodiment of the pressure generator 140 , This includes an outer housing 141 for releasable attachment to the hydraulic unit 30 , In the outer casing 141 There is a cylindrical cavity in which a piston 144 is slidably guided and a hydraulic pressure chamber 145 from a pyrotechnic chamber 146 separates. The latter in turn stands with a pyrotechnic propellant 143 in Connection, as a unit from the outside in the pressure generator 140 can be used. As in the first and second embodiment variant, the pressure generator 140 a common pressure chamber 145 for both brake circuits, which via outlet openings 147 and 148 are connected. In contrast to the first and second embodiment, however, in each working position of the piston 144 a separation of the brake circuits via check valves 161 and 162 guaranteed. In the in 7 illustrated outlet communicate both outlet openings 147 and 148 with the hydraulic pressure chamber 145 ,

The check valves 161 and 162 are in 11 exemplified. These each have a valve block 163 on, by means of seal via O-rings in corresponding recesses both on the pressure generator 140 as well as on the hydraulic unit 30 is inserted and held in position. The check valves 161 and 162 open in the direction of the hydraulic unit 30 and lock in the direction of the pressure generator 140 ,

The piston 144 is about a first seal 152 opposite the hydraulic pressure chamber 145 and a second seal 156 opposite the pyrotechnic chamber 146 sealed. Between these seals, a vent communicating with the outside environment is arranged to prevent overflow of combustion gases on the piston 144 over into the hydraulic pressure chamber 145 effectively prevent.

In the in the 7 and 8th illustrated embodiment, the seals 152 and 156 in recesses of the outer housing 141 on both sides of a likewise in the outer housing 141 trained ventilation ducts 157 arranged and sealed against an outer peripheral portion of the piston, respectively 144 ,

The seals 152 ' and 156 ' but also on the piston 144 ' be arranged, as in the fourth embodiment according to the 9 and 10 is shown. Incidentally, this functionally corresponds to the third embodiment.

Further, in the embodiments of FIGS 7 to 10 Means for automatically fixing the piston 144 respectively. 144 ' be provided in the disengaged end position, for example in the form of one or more radially acting spring elements between the piston and the housing inner wall 142 respectively. 142 ' which are released in a disengaged end position so as to block the piston against the cylinder liner.

In the 12 to 15 are two other variants of the pressure generator 240 respectively. 240 ' shown. These each comprise an outer housing 241 respectively. 241 ' for releasable attachment to the hydraulic unit 30 , In the outer casing 241 There is a cylindrical cavity in which a main piston 244 respectively. 244 ' is slidably guided and a hydraulic pressure chamber 245 respectively. 245 ' from a pyrotechnic chamber 246 respectively. 246 ' separates. The latter stands with a pyrotechnic propellant 243 respectively. 243 ' in connection, as a unit from the outside z. B. sealed by means of O-rings in the pressure generator 240 respectively. 240 ' can be used.

The hydraulic pressure chamber 245 respectively. 245 ' is by a floating piston 263 respectively. 263 ' in two sub-chambers 245a and 245b respectively. 245a ' and 245b ' divided. Each sub-chamber is hydraulically connected to a brake circuit, including the circumference of the cylinder liner 242 respectively. 242 ' corresponding outlet openings 247 respectively. 247 ' and 248 respectively. 248 ' are formed. The floating piston 263 respectively. 263 ' rests on a front end of the hydraulic pressure chamber 245 respectively. 245 ' as well as on the main piston 244 respectively. 244 ' about springs 264 and 265 respectively. 264 ' and 265 ' axially. This ensures positioning of the pistons in their starting position.

In the fifth embodiment according to the 12 and 13 are between the floating piston 263 and the cylinder liner 242 two seals 252 and 253 arranged, which in recesses of the outer housing 241 sit and against the cylindrical outer circumference of the floating piston 263 tight.

The main piston 244 is opposite the hydraulic pressure chamber 245 about a first seal 255 and opposite the pyrotechnic chamber 246 over a second seal 256 sealed. These seals are also in recesses of the outer housing 241 received and sealed against the outer circumference of the main piston 244 from. Between these seals 255 and 256 is provided a communicating with the outside environment venting, here by way of example in the form of a through the outer housing 241 leading ventilation ducts 257 is trained. The ventilation duct 257 flows between the seals 255 and 256 for the hydraulic pressure chamber 245 and the pyrotechnic chamber 246 in between the outer circumference of the main piston 244 and the cylinder liner 242 formed gap.

A feather 250 passing through the piston 244 initially in a wall recess 251 of the outer casing 241 is kept relaxed in the disengaged end position of the piston 244 and blocks it, in turn, the floating piston 263 blocked.

In a sixth embodiment according to the 14 and 15 are the seals 252 ' . 255 ' and 256 ' on the piston 244 ' established. The ventilation duct 257 ' opens in this case in a disengaged end position of the main piston 244 ' between the seals 255 ' and 256 ' of the main piston 244 ' for the hydraulic pressure chamber 245 ' and the pyrotechnic chamber 246 ' so on the seal 256 ' Be sent out pressed combustion gases to the outside environment.

The 16 and 17 show a seventh embodiment of a pressure generator 340 , This has an outer housing 341 for releasable attachment to the hydraulic unit 30 , In a cavity of the outer housing 341 is a main piston 344 slidably guided.

This separates a hydraulic pressure chamber 345 from a pyrotechnic chamber 346 , The pyrotechnic chamber 346 stands with a pyrotechnic propellant 343 in connection, which is inserted as a unit from the outside into the cylindrical cavity and seals it. The propellant 343 is axially between an annular holder 367 that about seals 370 opposite the housing inner wall 342 and against the propellant 343 is sealed, and an annular counter-holder 368 held in place in the cylindrical cavity and out through a locking ring 369 are axially fixed.

The hydraulic pressure chamber 345 is by a floating piston 363 in two sub-chambers 345a and 345b divided. Each compartment is over an outlet opening 347 respectively. 348 hydraulically connected to a brake circuit. The floating piston 363 is supported by a first spring 364 at a front end of the hydraulic pressure chamber 345 and by means of a second spring 365 on the main piston 344 axially. About the springs 364 and 365 ensures positioning of the two pistons in their original position. A conical design of the springs 364 and 365 allows a small block length, allowing the outer case 341 shorter.

For venting the brake circuits, the first sub-chamber 345a a frontal opening 359 through, through a plug or vent nipple 360 is shut off. The second compartment 345b Can have a radial vent 366 in the case 341 be vented. At the floating piston 363 are one or more corresponding radial openings 371 provided, which in the starting position a connection to the vent 366 enable.

The seventh embodiment is characterized by a small number of sealing elements. In addition, the seal of the pyrotechnic pressure chamber 346 and the latching element on the main piston 344 arranged and together form a unit 356 ,

The furthest into the pyrotechnic pressure chamber 346 dipping end portion of the main piston forms for this purpose on its outer circumference a receiving groove for the annular sealing and latching element 356 out, against the inside of the housing 342 seals. The latter has a wall recess 351 on, with the sealing and latching element 356 in a triggered end position of the main piston 344 engaged and positively interlocked, so that the main piston 344 is held in the final position. In the wall recess 351 conducts a ventilation channel 357 , About the combustion gases, which the sealing and latching element 356 overcome, be discharged to the environment.

For the main piston 344 is also in the direction of the first sub-chamber 345a an additional seal 355 to the housing 341 intended. In addition, for the floating piston 363 a seal 352 to the housing 341 intended. For this purpose, the housing inner wall 342 corresponding annular grooves for receiving O-rings or the like.

Instead of a positive locking of the main piston 344 in the triggered end position, a frictional locking is possible, as in the 18 and 19 is shown.

18a shows for this purpose an annular sealing element 380 and separate a latching element 381 in their own recesses on the outer circumference of the main piston 344 ' , The sealing element sits 380 closer to the end of the piston than the latching element 381 , The latter is as a wedge with an inclined surface 382 formed by means of a spring 384 against a corresponding inclined surface 383 in the associated recess of the main piston 344 is pressed, so that the wedge tends to the corresponding inclined surface 383 aufzugeleiten and against the housing inner wall 342 to press. At a release of the main piston 344 The wedge is caused by friction on the housing inner wall 342 pushed into its recess, making this the movement of the main piston 344 not impaired. An opposite movement of the piston 344 However, it is prevented by the wedge, so that the piston 344 is held in its final position, as in 18b is shown.

At the in 19 shown variant comes instead of a wedge a spring-loaded ball 390 used in the final position with a corresponding inclined surface 383 of the main piston 344 wedged.

The The invention has been described above with reference to exemplary embodiments explained in more detail. However, she is not on this Embodiments limited, but includes all embodiments defined by the claims.

10

Pressure generator

11

brake pedal

12

Brake booster

13

Master Cylinder

14

pressure line the first brake circuit between the master cylinder and the hydraulic power unit

15

pressure line the second brake circuit between the master cylinder and the hydraulic power unit

16

Pressure fluid reservoir

20

wheel brake

30

hydraulic power unit

31

Return pump

32

accumulator

33

channel

34

channel

35

channel

36

channel

40 40 '

pressure generator

41 41 '

outer casing

42 42 '

Housing inner wall

43 42 '

propellant

44 44 '

piston

45, 45 '

hydraulic pressure chamber

46 46 '

pyrotechnic chamber

47 47 '

outlet for the first brake circuit

48 48 '

outlet for the second brake circuit

49, 49 '

radial opening on the piston

50, on 50 '

feather

51 51 '

wall recess

52 52 '

poetry

53 53 '

poetry

54 54 '

poetry

55, 55 '

poetry

56 56 '

poetry

57 57 '

vent channel

58 '

wall recess on the outer circumference of the piston

59, 59 '

opening

60 60 '

Plug

140 140 '

pressure generator

141 141 '

outer casing

142, 142 '

Housing inner wall

143 143 '

propellant

144 144 '

piston

145 145 '

hydraulic pressure chamber

146 146 '

pyrotechnic chamber

147 147 '

outlet for the first brake circuit

148 148 '

outlet for the second brake circuit

152 152 '

poetry

155

poetry

156 156 '

poetry

157, 157 '

vent channel

159

opening

160

Plug

161 161 '

check valve

162 162 '

check valve

163

manifold

240 240 '

pressure generator

241 241 '

outer casing

242 242 '

Housing inner wall

243 243 '

propellant

244 244 '

main piston

245a, 245a '

first Partial chamber of the hydraulic pressure chamber

245b, 245b '

second Partial chamber of the hydraulic pressure chamber

246 246 '

pyrotechnic chamber

247, 247 '

outlet for the first brake circuit

248 248 '

outlet for the second brake circuit

250 250 '

feather

251 251 '

wall recess

252 252 '

poetry

255 255 '

poetry

256 256 '

poetry

257, 257 '

vent channel

259

opening

260

Plug

263 263 '

floating piston

264 264 '

axial spring

265, 265 '

axial spring

340

pressure generator

341

outer casing

342

Housing inner wall

343

propellant

344

main piston

345a

first Partial chamber of the hydraulic pressure chamber

345b

second Partial chamber of the hydraulic pressure chamber

346

pyrotechnic chamber

347

outlet for the first brake circuit

348

outlet for the second brake circuit

351

wall recess

352

poetry

355

poetry

356

Seals and latching element

357

vent channel

359

opening

360

Plug (Bleed nipple)

363

floating piston

364

conical axial spring

365

conical axial spring

366

Entlüfungsöffung for the second brake circuit

367

holder

368

backstop

369

circlip

370

sealing ring

371

radial opening

380

poetry

381

latching element (Wedge)

382

sloping surface at the latching element

383

corresponding sloping surface

384

feather

390

Bullet

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 3019364 C2 [0004, 0004]
• WO 2006/061279 A1 [0005]

Claims (21)

A vehicle brake system comprising: a pressure generator ( 10 ) for generating a hydraulic brake pressure, wheel brakes ( 20 ) connected to the pressure generator ( 10 ) are hydraulically connected, a hydraulic power unit ( 30 ) which is hydraulically connected between the pressure generating device ( 10 ) and the wheel brakes ( 20 ) and via which the brake pressure at the individual wheel brakes ( 20 ) is individually adjustable, characterized in that a pyrotechnic pressure generator ( 40 ) for two brake circuits on the hydraulic unit ( 30 ), which is a pyrotechnic piston ( 44 ) and when activated generates a brake pressure for full braking. Vehicle brake systems according to claim 1, characterized in that the pressure generator ( 40 ) a hydraulic pressure chamber ( 45 ), which by the piston ( 44 ) from a pyrotechnic chamber ( 46 ) is separated and at least during an intermediate position of the piston ( 44 ) is hydraulically connected between axial end positions with two brake circuits. Vehicle brake systems according to claim 2, characterized in that the hydraulic pressure chamber ( 245 ) by another piston ( 263 ) into two subchambers ( 245a . 245b ) and each sub-chamber ( 245a . 245b ) is hydraulically connected to a brake circuit. Vehicle brake systems according to one of claims 1 to 3, characterized in that the piston ( 44 ) in its axial settings individual or all outlets ( 47 . 48 ) shuts off to the brake circuits. Vehicle brake system according to one of claims 1 to 4, characterized in that the brake circuits in each case via a in the direction of the respective brake circuit opening check valve ( 161 . 162 ) to the hydraulic pressure chamber ( 145 ) are connected. Vehicle brake system according to one of claims 1 to 5, characterized in that the pressure generator ( 40 ) an outer housing ( 41 ), in which the slidably movable in this guided piston ( 44 ) a hydraulic pressure chamber ( 45 ) from a pyrotechnic chamber ( 46 ) and that the pressure generator ( 40 ) via the outer housing ( 41 ) is releasably attached to the hydraulic unit. Vehicle brake system according to claim 6, characterized in that the pressure generator ( 40 ) to the hydraulic unit ( 30 ) is screwed. Vehicle brake systems according to one of claims 1 to 7, characterized in that the pressure generator ( 40 ) a pyrotechnic propellant ( 43 ), which with the pyrotechnic chamber ( 46 ). Vehicle brake system according to claim 8, characterized in that the pyrotechnic propellant charge ( 43 ) is a replaceable unit. Vehicle brake system according to one of claims 1 to 9, characterized in that the piston ( 44 ) relative to a hydraulic pressure chamber ( 45 ) and a pyrotechnic chamber ( 46 ) is sealed and between these seals a communicating with the outside environment vent is arranged. Vehicle brake system according to claim 10, characterized in that for sealing gaskets ( 55 ' . 56 ' ) on the piston ( 44 ' ) are arranged and for venting in a piston ( 44 ' ) leading housing ( 41 ' ) at least one venting channel ( 57 ' ) is formed, which in a disengaged end position of the piston ( 44 ' ) between the seals ( 55 ' . 56 ' ) for the hydraulic pressure chamber ( 45 ' ) and the pyrotechnic chamber ( 46 ' ) opens. Vehicle brake system according to claim 10, characterized in that for sealing gaskets ( 55 . 56 ) on one of the pistons ( 44 ) leading housing ( 42 ) are arranged and on the housing ( 42 ) at least one venting channel ( 57 ) formed between the seals ( 55 . 56 ) for the hydraulic pressure chamber ( 45 ) and the pyrotechnic chamber ( 46 ) opens. Vehicle brake system according to one of claims 1 to 12, characterized in that the pyrotechnically generated hydraulic brake pressure of the pressure generator ( 40 ) via channels ( 33 . 34 ) in the hydraulic unit ( 30 ) downstream of ASR valves of the brake circuits in to the wheel brakes ( 20 ) leading channels ( 35 . 36 ). Vehicle brake system according to claim 13, characterized in that the channels ( 33 . 34 ) for the initiation of the pyrotechnically generated hydraulic brake pressure downstream of the wheel brakes ( 20 ) associated with inlet valves. Vehicle brake system according to one of claims 1 to 14, characterized in that the pressure generator ( 40 ) Has means which automatically fix the piston after its actuation in its disengaged end position. Vehicle brake system according to one of claims 1 to 15, characterized in that between the piston ( 44 ) and the leading one Housing inner wall ( 42 ) one or more radially acting spring elements ( 50 ) are arranged, which in a position of the piston ( 44 ) are held biased in a disengaged end position, however, are released in such a way to the piston ( 44 ) opposite the housing inner wall ( 42 ) to block. Vehicle brake system according to claim 15, characterized in that the spring element on the piston ( 344 ) in a disengaged end position of the piston ( 344 ) with a wall recess of the housing ( 341 ) engages positively. Vehicle brake system according to claim 16, characterized in that the spring element the piston ( 344 ) opposite the housing inner wall ( 342 ) seals. Vehicle brake system according to one of claims 1 to 15, characterized in that on the piston ( 344 ) a blocking device ( 380 . 390 ) is arranged, which in a disengaged end position of the piston ( 344 ) in cooperation with the housing inner wall ( 42 ) a return movement of the piston ( 344 ) frictionally blocked. Vehicle brake system according to one of claims 1 to 19, characterized in that upon activation of the pyrotechnic pressure generator ( 40 ) the connection of the wheel brakes ( 20 ) to the pressure generating device ( 10 ) upstream of the pressure introduction of the pressure generator ( 40 ) is shut off. Vehicle brake system according to claim 20, characterized that the shut-off via the ASR valves of the brake circuits he follows.