DE102004014808A1 - Device for monitoring the position and movement of a brake pedal - Google Patents

Abstract

The invention relates to a device for monitoring the position and movement of a brake pedal, comprising a master cylinder 1; 102 with integrated position transmitter for monitoring the position of a piston 2; 105 within a housing 6; 103 for use within a regulated braking system for motor vehicles, in particular with driving dynamics control, the position transmitter being a magnet 35; 150 as a signal generator, which has a magnetic field in the direction of a sensor element 36; 151 sends out, which is stationary on the housing 6; 103 is arranged, and can be connected to an electronic control unit. DOLLAR A In order to enable monitoring of a push rod piston even during a driving dynamics control process, it is proposed that the magnet 35; 150 between two pistons 2, 3; 105, 106 arranged, and relative to at least one of the pistons 2, 3; 105, 106 is slidably provided. DOLLAR A This results in a relative displaceability of the magnet 35; 150 with respect to a fixed piston 3; 106 and a proportional displacement of the magnet 35; 150 with respect to an actuated piston 2; 105 enables when the piston 3; 106 during a braking operation during a driving dynamics control operation due to closed isolation valves relative to the housing 6; 103 is immovable.

Description

devices for surveillance positions and movements of a brake pedal are generally known.

Out WO 02/43996 A1 discloses a pedal-operated master cylinder, which is provided with an integrated position transmitter for monitoring the position of a displaceable first piston within a cylinder housing Use within a regulated braking system for motor vehicles to allow wherein the piston has a magnet as a signal generator, which a Sends magnetic field in the direction of a sensor element that is stationary on the housing is arranged.

The Sensor arrangement is for driver-initiated braking designed in normal operation, in which the piston to be monitored has a defined one actuating back sets. The magnet is by means of a spring element that is in contact with a End on a case back supported, acted upon and thus relative to the push rod piston on one stationary component supported.

at Modern vehicle dynamics control systems perform a vehicle dynamics control process regularly to that one usually constantly opened hydraulic connection between master cylinder and wheel brakes automatically is interrupted so that the piston during braking during the Driving dynamics control process (ESP control intervention) as a result of closed Isolation valves relative to the housing so to speak is immovable. One reason for this is that there is no pressure medium displaced towards wheel brakes can be. The ESP intervention is driver-independent and the rudimentary Piston travel is not sufficient to move the magnet into the area of the sensor element to postpone. The ESP process can also not be done by the driver be interrupted so that only a limited delay is possible. Furthermore, there is no actuation signal can be generated and, for example, no brake light signaling respectively. The back traffic is only after the vehicle dynamics control process has been completed The driver's braking request is notified.

It would be now possible, for the use a separate brake light switch, which senses brake pedal actuation. However, the number of parts and especially the assembly of brake light switches in the footwell of a motor vehicle as too expensive considered.

It therefore a solution applies for the Offer problems, even during a driving dynamics control process reliable monitoring of a piston enable.

to solution This task suggests that the magnet be between two Pistons arranged, and displaceable relative to at least one of the pistons is provided. As a result, the piston is together with its arrangement components so to speak suspended floating. In further clarification The invention provides spring means with which the magnet held between the pistons and at least one of the pistons is arranged relatively displaceable. The magnet is therefore not slavishly by means of a spring between the housing and the piston fixed to the piston, but somewhat elastic clamped between two pistons. This elasticity of the magnetic clamping allows therefore an improved, and adapted to different operating conditions Signal generation with a relative displacement of the magnet.

It it makes sense to use the magnet together with associated components such as in particular to provide the spring as an assembly which is preassembled, and thereby more easily introduced into the master cylinder housing during final assembly can be.

In a further embodiment of the invention, the spring means comprise a supported on the first piston Return spring and one supported on the magnet additional spring means, the additional spring means having greater flexibility has as the return spring. Depending on whether the movement and the control of the magnet in Row or parallel to the movements of the two pistons the other spring means is on the second piston or on a component that can be moved by the displacement of the first piston supported.

In dependence the piston displacement becomes one by the compliance defined magnetic displacement enables.

The In an advantageous embodiment of the invention, sensor element comprises a Hall element, which is not just a switching function, but in principle even enables a linear position detection of the piston, if desired is.

The second piston can be means for guiding the Have magnets so that a precise signal generation is made possible. The piston preferably has a peg-shaped piston section, which of the leadership the magnet serves and without much effort can be molded onto this during the manufacture of the piston.

The utilization of the magnetic material is further improved if a carrier made of non-magnetic material is arranged between the magnet and the piston section, and if the Magnet is arranged in the axial direction between disks made of an iron material, so-called pole disks.

The Enable washers bundling of the magnetic field, so that the wall thickness of the housing can be made sufficiently thick can also withstand high pressure loads. simultaneously the force on the magnet is homogenized by this spread over a larger area and the magnet will break through the disks in the event of a break held together.

The The magnet can, for example, be designed in a ring shape, whereby the sensor element theoretically in any position on the circumference of the housing can be arranged.

As well it is possible within the scope of the invention not to design the magnet in a ring shape, with a correct position Arrangement and leadership of the magnet on the piston of the sensor element is necessary.

Preferably is the carrier designed in one piece and essentially cylindrical, he has a collar for axial contact of the magnet and on the piston section a stop to limit the relative displacement of the wearer with respect is provided on the piston. The other spring means is one advantageous embodiment supported on the piston. As a result, an assembly formation on the second piston can be included of the magnet become.

The to disposal standing length is used efficiently by at least partially the return spring inside a pot-shaped Wall of the piston is arranged, and in the middle of a pin is penetrated with a stop on which a sleeve is fixed in such a way so when actuation shift of the piston the means for guiding the Immerses the magnet axially and telescopically into the interior of the sleeve.

A easy manufacture of the carrier is achieved by the carrier according to an advantageous Development of the invention a first cylindrical section and has a second cylindrical portion, the magnet arranged on the second cylindrical portion of the carrier and the carrier with its second cylindrical section on the piston section of the led second piston is. For guidance and the anti-rotation device preferably points radially inwards directed projections on which engage in recesses of the second piston section. Thereby becomes a precise Signal generation enabled.

A Further assembly formation is facilitated by the carrier in several parts is designed and a spring sleeve as well as a magnetic sleeve has, being on the spring sleeve radially outward projections are provided, which for connection to the magnetic sleeve between radially inward projections of the magnetic sleeve arranged are, the protrusions for guidance and Protection against rotation of the carrier on the piston section in recesses of the second piston section intervene and the magnet is arranged on the magnetic sleeve.

at one embodiment the invention is the return spring and the further spring means based on a (spring) cage elastically pre-tensioned that an actuation shift of the piston a compression of the return spring and an expansion further allows spring means relative proportional displacement of the magnet to allow on the piston. The summary of the magnet as well of the spring elements within the assembly of the spring cage enables one rational assembly because, for example, the correct assembly of the magnet on the assembly can be checked.

In Another advantageous embodiment of the invention has a spring cage Sleeve for Storage of the magnet and a, thereon limitedly arranged and by return spring and Spring means acted upon spring receptacle, which during an actuation shift of the piston can be placed against the second piston in such a way that the sleeve and Magnet with expansion of the spring means relative to the second piston in the direction of actuation be moved. The expansion of the spring means is made possible by the piston displacement and compression of the return spring Capturing the sleeve is reduced to a push rod.

In The cage has an advantageous development of the invention first sleeve and a second sleeve for preloading the return spring as well as a carrier on, with an actuation shift of the Piston the magnet with expansion of the further spring means relative to the piston in the direction of actuation is moved. The expansion of the spring means is made possible by moving the piston and compressing the return spring the bondage of the second sleeve is reduced to a push rod.

According to a further advantageous embodiment, the magnet is arranged in a guided manner on the second sleeve and the carrier has radially outwardly directed projections which are guided in recesses in the second sleeve. The magnet is preferably between disks in the axial direction arranged from an iron material, which have radially inwardly directed projections and webs which are guided in the recesses of the second sleeve. The second sleeve advantageously has a shoulder on the inside and the further spring means is arranged between the shoulder and the disk in a prestressed manner. This enables precise signal generation.

A another advantageous embodiment of the Invention provides a further spring means between the first Sleeve and the carrier to arrange biased.

at Advantageous further developments of the invention are simple positioning of the sensor element enables by arranging the sensor element in a receptacle, which can be fixed to the housing in a defined position. The advantages occur especially when the recording in the direction of actuation a piston and adjustable relative to the housing and in one defined position is fixable.

advantageous Interchangeability is given when the sensor element is used together with rigid conductor elements form-fitting is included in the recording, and if an electrical connection line can be inserted into a connector of the receptacle.

A Defined positioning is possible if the housing has a Stop for has the recording, and if between stop and recording in Your distance measure exactly tolerated distance elements for the provision of a defined distance are arranged.

A Position-neutral positioning of the components to be assembled peripherally will be possible if the receptacle is arranged between two pressure medium inlet bores in the housing is. This enables a push rod piston to be sensed. According to one other design with secondary piston sensing is the recording at one end of the housing intended.

The Drawing shows advantageous embodiments of the invention in section, which are described in detail below.

In addition to wheel brakes, a vehicle brake system includes a hydraulic unit connected to it by means of pipes and hoses with valves that are open or closed when de-energized (inlet, outlet, isolating and changeover valves, the latter serving to change the suction line of the pump for the purpose of generating pressure in at least one wheel brake) as well as an integrated return pump or booster pump and a pedal-operated master cylinder 1 , with a first and a second piston 2 . 3 for first and second pressure rooms 4 . 5 , with the pistons 2 . 3 for supplying pressure medium to wheel brakes combined in pairs in brake circuits, displaceable within a housing 6 are arranged. It is understood that the master cylinder 1 A brake booster can be connected upstream to generate a servo force, even if this task can basically be fulfilled by another source of pressure increase, such as the pump.

The master cylinder 1 the 1 to 5 is of the so-called plunger type with stationary in a housing wall 7 arranged, and on a piston wall 8th . 9 with a sealing lip 10 . 11 adjacent sealing sleeves 12 . 13 for sealing the pressure rooms 4 . 5 , The sealing lips 10 . 11 can be overflowed in the direction of the wheel brake if a pressure drop is set between the pressure medium reservoir (not shown) and the wheel brake.

For the unactuated operating state is also between the two pressure rooms 4 . 5 enables a pressure-equalizing connection so that there is a general pressure equalization between the two brake circuits for this unactuated operating state.

Each of the pistons 2 . 3 is a return spring 14 . 15 assigned which one end 16 . 17 on a piston crown 18 . 19 and with another end over a collar 20 . 21 a sleeve 22 . 23 indirectly on the housing 6 is supported. The return spring 14 . 15 is compressed in an actuation direction A when the piston is displaced, and expanded for the purpose of piston return.

The following will describe the embodiment in detail 1 received. Starting from the piston crown 18 . 19 have the pistons 2 . 3 over a pot-shaped wall 24 . 25 within which the return spring 14 . 15 is at least partially arranged. The wall 24 . 25 is centered by a central pin 26 . 27 protrudes through the axial exit from the wall 24 . 25 ends. That end 28 . 29 is with a stop 30 . 31 for the sleeve 22 . 23 provided with a collar 32 . 33 interacts in such a way that the sleeve 22 . 23 relative to the tenon 26 . 27 is telescopic to a limited extent. In other words, the sleeve 22 . 23 with return spring 14 . 15 pushed into the inside of the piston when actuated. As can be seen, the attack is 30 . 31 preferably by one, on the pin 26 . 27 riveted - especially wobble riveted - ring disc. The other end of the sleeve 22 . 23 has the plate-like collar 20 . 21 for the return spring 14 . 15 ,

The second piston 3 also has one, the cone 27 opposed peg-shaped piston section 34 , which as a means of guiding a permanent magnet 35 serves.

The magnet 35 serves as a signal transmitter for a position transmitter and sends a magnetic field radially in the direction of a sensor element 36 - Preferably in the form of a Hall sensor, a magnetoresistive sensor or a reed contact - made of, which is stationary on the housing 6 is provided and can be connected to an electronic control unit (not shown) in order to enable a position detection. It should be taken into account that a Hall sensor or a magnetoresistive sensor as an active component also requires a power supply, while a reed contact as a controlled switch is only effective as a break or make contact in a circuit. The sensor element 36 can also have local intelligence in the form of a so-called ASIC (Application Specific Integrated Circuit) for the purpose of better networking within a bus system.

The magnet 35 is ring-shaped and as can be seen between discs 37 . 38 made of magnetic material on a cylindrical support 39 made of non-magnetic material, which over a collar 40 for the axial contact of the magnet 35 features. The carrier 39 is on the peg-shaped piston section 34 limited displacement and to limit the travel of the magnet 35 with an end stop 41 provided, as the stop described above 30 . 31 can be trained. How out 1 emerges is the carrier 39 with the magnet 35 on the one hand by the return spring 14 of the first piston 2 and on the other hand by another spring means 42 which on the second piston 3 is supported, so that the magnet 35 in a way between the pistons 2 . 3 and is slidably clamped relative to these. The spring force of the return spring 14 is, however, greater than the spring force of the further spring means 42 , This results in an actuation-related shift of the magnet 35 allows even if the second piston 3 is fixed immovably due to a driving dynamics control.

With the other spring means 42 it is in contrast to the return springs 14 . 15 visible around a conical coil spring.

The embodiment according to 1 has the advantage of being the carrier 39 for the magnet 35 - If there is a leak in the area of the second piston 3 (Secondary brake circuit) - at the same time to support the first piston 2 (Push rod piston) serves by the carrier 39 after compression of the spring means 42 at the piston 3 arrives.

The embodiment according to 2 largely agrees with the embodiment 1 so that matching features are identified by matching reference numerals, and repetition of the relevant parts of the description is dispensed with. Therefore, only the main differences are dealt with below.

The carrier 50 for the magnet 35 is designed as a non-magnetic sleeve, which is part of a cage 51 for the return spring 14 is. The cage 51 has the sleeve, a spring mount 52 , a push rod 53 as well as another sleeve 54 on. The two sleeves (carrier 50 . 54 ) and the push rod 53 are telescopic to a limited extent by means of mutual stops and, according to this embodiment, bring about an elastic prestressing of the return spring in the unactuated state 14 , The spring mount 52 is inside a recess 55 in the axial direction relative to the sleeve (carrier 50 ) slidably, and is supported on a front of the peg-shaped piston section 34 off, which also causes the return spring 14 on the spigot 34 is supported. In the event of actuation-related compression of the return spring 14 allows the push rod to be moved 53 an expansion of the further spring means 42 , which is designed in this embodiment as a cylindrical coil spring. This will cause the magnet to shift 35 in the area of the sensor element 36 allows. If there is a pressure loss (leakage) in the secondary circuit of the piston 3 takes place via the push rod 53 a central, direct support for the piston 2 (Push rod piston) on the piston 3 (Secondary piston).

The 3 illustrates in a cross section in particular the described components sleeve (carrier 50 ), Spring mount 52 , Return spring 14 and housing 6 ,

Interchangeability and adjustability of a sensor element 36 to enable this is in accordance with 4 and 5 in one shot 60 arranged in a defined position on the housing 6 is fixable. Here is the sensor element 36 as an interchangeable unit together with rigid conductor elements in a form-fitting manner in the receptacle 60 added. An electrical connection line serves for the electrical connection to an electronic control unit of the brake system or another control unit on the vehicle and networked with the brake system 61 with a connector 62 in the recording 60 is insertable.

So far no adjustability of the recording 60 is required, this can be attached to a base of the housing 6 are screwed on, with defined walls or contact surfaces on the base Creation of the recording 60 can be provided. In this context, it is useful when recording 60 has a housing made of plastic material, the outer wall of which is provided on the base side in the region of contact surfaces with contact lugs which are located when mounting the receptacle on the housing 6 Deform by firm contact with the contact surfaces in such a way that there is no backlash fastening of the receptacle.

In another modification, adjustability is ensured by the inclusion 60 in the direction of actuation of a piston 2 . 3 as well as relative to the housing 6 is adjustable and fixable in a defined position. To 4 points the case 6 a stop 63 for receiving 60 on, between stop 63 and recording 60 at least one precisely tolerated spacer 64 to ensure a defined relative position between the sensor element 36 and pistons 2 . 3 are provided. In principle, the admission 60 for monitoring the position of a push rod piston (piston 2 ) space-saving between two pressure medium tank connections 65 . 66 be arranged. According to 4 is the recording 60 however provided at one end of the housing, which ensures good accessibility of the device. A separate bracket is used 67 between admission 60 and sensor element 36 as a positive locking element against loosening.

The 5 illustrates the sensor element with receptacle in a schematic plan view 60 ,

The movement and control of the magnet 35 take place in the embodiments according to the 2 to 5 parallel to the movements of the two pistons 2 . 3 ,

The master cylinder of the 6 to 19 is a so-called central valve tandem master cylinder 102 designed. In its basic structure, this has a housing 103 with longitudinal bore 104 for a first piston (push rod piston) 105 and a second piston (floating piston) 106 on. Furthermore, each piston 105 . 106 a central valve 107 . 108 intended. The respective central valve 107 . 108 interacts to seal an associated pressure chamber 109 . 110 with the respective piston 105 . 106 taking into account a given closing path.

From an expansion tank, not shown, open via connections 111 . 112 supply channels 113 . 114 each in trailing rooms 115 . 116 which by means of primary sealing sleeves 117 . 118 compared to the associated pressure rooms 109 . 110 are sealed. Next is the trailing room 116 using a secondary sealing collar 119 compared to the first pressure room 109 sealed, the secondary sealing collar 119 in a circumferential groove 120 of the second piston 106 is arranged.

One in a recess 122 arranged sealing arrangement 121 seals the trailing space 115 towards the atmosphere. The sealing arrangement 121 is on the pressure room 109 facing side of a disc 123 limited, being a fuse element 125 the sealing arrangement 121 as well as the disc 123 in the recess 122 guaranteed.

The sealing arrangement 121 has a guide ring 126 , which consists of a plastic and a low-wear guide of the first piston 105 serves, as well as one on the guide ring 126 in the direction of the first pressure chamber 109 arranged secondary sealing collar 127 on.

The central valves 107 . 108 are in an unactuated state by stops designed as cylindrical pins 128 . 129 kept open, the stops 128 . 129 through slot-shaped recesses 130 . 131 The piston 105 . 106 extend. The attack 128 is in the longitudinal bore 104 arranged, being on the disc 123 strikes. The stop is against it 129 in a housing bore 132 of the housing 103 fixed and the slit-shaped recess 131 of the second piston 106 is in an area between the primary boot seal 118 and the secondary boot seal 119 arranged.

Each of the pistons 105 . 106 is a return spring 133 . 134 assigned which with a first end 135 . 136 on a first sleeve 137 . 138 and with a second end 139 . 140 on a second sleeve 141 or on a case bottom 142 is supported. The first sleeve 137 . 138 the return spring 133 . 134 is based on a first piston section 143 . 144 of the first and the second piston 105 . 106 from. When the piston moves in an actuation direction A, the return spring 133 . 134 compressed and expanded for piston return.

The operation of the central valve tandem master cylinder 102 is basically known. When a brake pedal, not shown, is actuated, the first piston 105 shifted to the left in actuation direction A. This linear movement of the first piston 105 closes the associated central valve 107 so that the corresponding pressure space 109 opposite its connection 111 via the wake channel 113 and the trailing space 115 to the expansion tank, not shown, is completed. As a result of the resulting hydrostatic pressure in the pressure chamber 109 becomes the second piston 106 in sync with the first piston 105 moves in actuation direction A and closes its central valve in the associated brake circuit 108 , Now hydraulic pressure builds up in this brake circuit in the same way, because the pressure chamber there 110 towards its connection 112 via the overflow channel 114 and the trailing space 116 is closed to the expansion tank. Consequently, there is pressure in both pressure rooms 109 . 110 practically the same hydraulic pressure that is transferred to wheel brakes, not shown.

The following will describe the embodiment in detail 6 received the central valve tandem master cylinder 102 shows in longitudinal section.

The return spring 133 of the first piston 105 is in a cage 145 held which is the first sleeve 137 , the second sleeve 141 as well as a push rod 146 has as components. The two sleeves 137 . 141 and the push rod 146 are on the push rod 146 trained stops 148 . 149 telescopic to a limited extent and in the unactuated state cause an elastic pretension of the return spring 133 ,

The second piston 106 has a second, peg-shaped piston section 147 on, whereby the second piston 106, in contrast to the known pistons, is extended and this extension is used as a means for guiding a permanent magnet 150 serves. The permanent magnet 150 , which in turn serves as a signal transmitter for a position transmitter and a magnetic field radially in the direction of a sensor element 151 - preferably in the form of a Hall sensor, a magnetoresistive sensor or a reed contact - sends out the stationary on the housing 103 is provided and can be connected to an electronic control unit (not shown) in order to enable a position detection. It should be taken into account that a Hall sensor or a magnetoresistive sensor as an active component also requires a power supply, while a reed contact as a controlled switch is only effective as an opener or closer of a circuit. The sensor element 151 can also have local intelligence in the form of a so-called ASIC (Application Specific Integrated Circuit) for the purpose of better networking within a bus system.

The magnet 150 is ring-shaped and as can be seen between discs 152 . 153 made of magnetic material on a cylindrical support 154 made of non-magnetic material, which over a collar 155 for the axial contact of the magnet 150 features. The carrier 154 is on the second piston section 147 limited displaceability, which limits the displacement of the carrier 154 and with it the magnet 150 with an end stop 156 is provided.

This ring shape of the magnet 150 it is possible the sensor element 151 not just in one like in 6 position and attach shown, but theoretically at any position along the circumference of the housing 103 ,

How out 6 emerges is the carrier 154 with the magnet 150 on the one hand by means of the second sleeve 141 from the return spring 133 of the first piston 105 and on the other hand by another spring means 157 which on the second piston 106 is supported, so that the magnet 150 in a way between the pistons 105 . 106 and is slidably clamped relative to these. The spring force of the return spring 133 is, however, greater than the spring force of the further spring means 157 , This results in an actuation-related shift of the magnet 150 allows even if the second piston 106 is immovably fixed due to a driving dynamics control, since the movement of the second sleeve 141 which is on the covenant 155 of the carrier 154 supports the movement of the magnet 150 and the pole disks 152 . 153 triggers.

This embodiment has like the embodiment according to 1 about the advantage that the carrier 154 for the magnet 150 - If there is a leak in the area of the second piston 106 (Secondary brake circuit) - at the same time to support the first piston 105 serves by the carrier 154 after compression of the spring means 157 at the piston 106 arrives.

The movement and control of the magnet 150 take place in this embodiment as in the embodiment according to

1 in series with the movements of the two pistons 105 . 106 ,

The embodiments according to those described below 7 to 19 allow a particularly space-optimized design, since the movement and control of the magnet 150 parallel to the movements of the two pistons 105 . 106 respectively.

The embodiments according to 7 to 19 agree with the embodiment with the exception of the movement and control of the magnet largely 6 agree, so that matching features are identified with matching reference numerals and repetition of related parts of the description is dispensed with. Therefore, only the main differences are dealt with below.

In contrast to the embodiment according to 6 in the embodiment according to FIGS 7 to 10 the cage 145 in which the return spring 133 of the first piston 105 is held, the first and a second sleeve 137 . 164 who have favourited Push Rod 146 , a non-magnetic, sleeve-shaped carrier 165 as well as another spring means 166 , whose spring force is less than that of the return spring 133 ,

In 8th is the section X of the 7 shown enlarged. From this it can be seen that the carrier 165 , which can be produced, for example, from a thin sheet metal material by a forming process, between the stop 148 the push rod 146 and the second sleeve 164 is arranged. Because the return spring 133 with its end 139 on the second sleeve 164 is the carrier 165 by preloading the second sleeve 164 by means of the return spring 133 in the direction of actuation A in their contact with the stop 148 held. The second sleeve 164 lies like out 7 and 8th emerges on the piston section 147 of the second piston 106 on.

The carrier 165 which in 9 is shown individually, has a first cylindrical portion 167 and a second cylindrical section 168 on, the second section 168 a larger diameter than the first section 167 having. The permanent magnet 150 as well as the disc 152 are on the second cylindrical section 168 of the carrier 165 arranged.

Especially from 7 is recognizable that the carrier 165 with its second cylindrical section 168 on the second piston section 147 of the second piston 106 is guided, with inward radial projections 169 to guide and prevent rotation of the carrier 165 in recesses 170 of the second piston section 147 intervention. The permanent magnet 150 So here is not immediate, but through the carrier 165 indirectly on the second piston section 147 of the second piston 106 guided.

A radially outward-facing collar 171 of the second section 168 serves to place the disc 152 and the magnet 150 , The other spring means 166 , which in the radial direction between the second sleeve 164 and the carrier 165 is arranged, lies with its first end 172 on an inside 174 the second sleeve 164 and with its second end 173 on the disc 153 at what the carrier 165 , the magnet 150 as well as the disks 152 . 153 biased in the 7 and 8th position shown are held.

Out 8th it can be seen that the second piston section 147 recesses 175 of the carrier 165 as well as recesses 176 the disc 153 , what a 10 is shown, reaches through and thus on the second sleeve 164 is applied.

If the second piston 106 is immovably fixed as a result of driving dynamics control, allows the return spring to be actuated due to actuation 133 the displacement of the push rod 146 an expansion of the further spring means in actuation direction A. 166 , The carrier 165 is with the magnet 150 and the two discs 152 . 153 thereby in the direction of actuation A in the area of the sensor element 151 postponed.

The embodiment according to the 11 to 14 differs from the embodiment described above according to FIGS 7 to 10 only in the design of the carrier 165 , which in the embodiment described below in two parts from a spring sleeve 177 and a magnetic sleeve 178 is constructed. Therefore, an overall view of a central valve tandem master cylinder 102 waived in longitudinal section for this embodiment.

11 shows a section through the central valve tandem master cylinder 102 along a line AA, which in 7 the embodiment described above is indicated.

Out 12 which is a section along the line BB 11 shows, it can be seen that the carrier 165 this embodiment from the two components spring sleeve 177 and magnetic sleeve 178 exists, but otherwise as for the 7 and 8th described on the plot 148 the push rod 146 is applied and by the return spring 133 or the biasing force of the return spring on the second sleeve 164 is held in the position shown. From the 13 and 14 which the spring sleeve 177 or the magnetic sleeve 178 show, the design is clear.

Especially from 13 it can be seen that the spring sleeve 177 a cylindrical section 179 and a circumferential, radially outward facing collar 180 having. From the federal government 180 kick two radial protrusions 181 which, on the one hand, the connection with the magnetic sleeve 178 and on the other hand the guidance and anti-rotation of the spring sleeve 177 in the recesses 170 of the second piston section 147 serve.

14 clarifies that the magnetic sleeve 178 also a cylindrical section 182 and a radially outward-facing collar 183 having. Next are radially inward projections 184 . 185 provided which on the one hand the connection with the spring sleeve 177 and on the other hand the guidance and anti-rotation of the magnet shell 178 in the recesses 170 of the second piston section 147 serve. The tabs 184 are on one edge 186 of the cylindrical section 182 intended. The tabs 185 can, for example, by means of the federal government's 183 be formed.

The magnet 150 is how out 12 can be seen on the cylindrical section 182 the magnetic sleeve 178 arranged and the disc 152 is due to the bias of the other spring means 166 on the covenant 183 the magnetic sleeve 178 on. The tabs 181 the spring sleeve 177 are in the assembled state of the carrier 165 between the ledges 184 and 185 the magnetic sleeve 178 intended. Because the ledges 181 . 184 . 185 in the recesses 170 are guided, the two components 177 . 178 do not twist against each other, thereby connecting the two components 177 . 178 is ensured.

The 15 to 19 show a further embodiment of the central valve tandem master cylinder 102 ,

The cage 145 in which the return spring 133 of the first piston 105 is held here comprises the first and a second sleeve 137 . 187 who have favourited Push Rod 146 , a non-magnetic, sleeve-shaped carrier 188 as well as another spring means 189 , whose spring force is less than that of the return spring 133 ,

How out 15 showing a section of a central valve tandem master cylinder 102 shows, emerges are the magnet 150 and the disks 152 . 153 on the second sleeve 187 arranged arranged. For this purpose, the second sleeve 187 how in particular 17 shows a first and a second cylindrical portion 190 . 191 and a circumferential collar arranged between them 192 on. The first cylindrical section 190 is with slot-shaped, axial recesses 193 provided, the magnet 150 on the first cylindrical section 190 is guided and the recesses 193 the leadership of the carrier 188 and the disks 152 . 153 serve.

Out 16 is recognizable that the carrier 188 is designed similar to the spring sleeve 177 according to 16 and a cylindrical section 194 and a circumferential, radially outward facing collar 195 having. From the federal government 195 radial protrusions occur 196 which of the leadership and anti-rotation of the wearer 188 in the recesses 193 the second sleeve 187 and the installation of the disc 152 serve. For this, the disc points 152 , what a 18 is shown, radially inward projections 197 on.

So is the disc 153 , in the 19 is shown with radial webs 198 provided which of the guidance and anti-rotation of the disc 153 in the recesses 193 the second sleeve 187 serve.

15 shows that the carrier 188 at the stop 148 the push rod 146 rests and between the stop 148 and the second sleeve 187 is arranged. The second sleeve 187 lies on the second piston section 147 at and the federal government 192 the second sleeve 187 serves to create the end 139 the return spring 133 and thus their preload. This also becomes the carrier 188 held in the position shown.

The other spring means 189 is between the disc 153 and one, on an inside 199 the second sleeve 187 located paragraph 200 kept biased.

If the second piston 106 is immovably fixed as a result of driving dynamics control, allows the return spring to be actuated due to actuation 133 the displacement of the push rod 146 in direction of actuation A. Since the second sleeve 187 on the second piston 106 is applied and not with the push rod 146 is moved, there is an expansion of the further spring means 189 , The carrier 188 is with the magnet 150 and the two discs 152 . 153 thereby in the direction of actuation A in the area of the sensor element 151 postponed.

The 20 serves to explain a brake system 70 with driving dynamics control (ESP), in which the invention can be used in particular. The braking system 70 comprises a braking device with a pneumatic brake booster 71 , the master cylinder 1 or 102 with a pressure medium reservoir 72 , pressure chambers of the master cylinder 1 . 102 via brake lines 73 . 74 with wheel brakes 75 - 78 are connected. The wheel brakes 75 - 78 are combined in pairs in so-called brake circuits I, II. In the case of brake circuits I, II, the so-called diagonal division with the combination of diagonally opposite wheel brakes of the front and rear axles of a vehicle has established itself, although in principle other division such as the so-called black / white division with paired combination of the wheel brakes of one axle is also possible.

A pressure sensor is used to record a pressure entered by the driver 79 on the brake line 73 which a pressure chamber with the wheel brakes 75 . 76 of brake circuit I connects. Every brake line 73 . 74 has electromagnetic isolation valves connected in series 80 . 81 as well as for every wheel brake 75 - 78 one inlet valve each 82 - 85 so like one exhaust valve each 86 - 89 on. The two wheel brakes 75 . 76 ; 77 . 78 of each brake circuit I, II are with a return line 90 . 91 connected, in their line branches per wheel brake 75 - 78 the exhaust valve in each case 86 - 89 is used. Downstream to the exhaust valves 86 - 89 is in every return line 90 . 91 a low pressure accumulator 92 . 93 that with an input of an electromotive driven pressure medium conveying device 94 . 95 is connected, which feeds the two brake circuits I, II. Between an outlet of each pressure medium delivery device 94 . 95 and the associated brake circuit I, II is by means of a pressure channel 96 . 97 and a branch 98 . 99 a hydraulic connection, the pressure increase in the wheel brakes 75 - 78 via the intake valves 82 - 85 is adjustable. This is about the pressure medium delivery devices 94 . 95 Pressure to intervene in driving stability or to brake the wheel brakes 75 - 78 can be controlled without having to use a central high-pressure accumulator as with electrohydraulic brake systems.

To switch between ABS return mode (direction of delivery in the direction of the master brake cylinder) and ASR or ESP driving dynamics control mode (direction of delivery in the direction of the wheel brakes) by means of the pressure medium delivery devices 94 . 95 To enable, is in the suction branch of each pressure medium delivery device 94 . 95 one switch valve each 100 . 101 integrated, which with active driving dynamics control a pressure medium connection between the master cylinder 1 and the entrance of the pressure medium conveying devices 94 . 95 able to manufacture.

1

master cylinder

2

piston

3

piston

4

pressure chamber

5

pressure chamber

6

casing

7

housing

8th

piston wall

9

piston wall

10

sealing lip

11

sealing lip

12

sealing sleeve

13

sealing sleeve

14

Return spring

15

Return spring

16

The End

17

The End

18

piston crown

19

piston crown

20

collar

21

collar

22

shell

23

shell

24

wall

25

wall

26

spigot

27

spigot

28

The End

29

The End

30

attack

31

attack

32

collar

33

collar

34

piston section

35

magnet

36

sensor element

37

disc

38

disc

39

carrier

40

Federation

41

attack

42

spring means

50

carrier

51

Cage

52

spring mount

53

pushrod

54

shell

55

recess

60

admission

61

connecting line

62

plug-in device

63

attack

64

spacer

65

Pressure fluid reservoir connection

66

Pressure fluid reservoir connection

67

clip

70

braking system

71

Brake booster

72

Pressure fluid reservoir

73

brake line

74

brake line

75

wheel brake

76

wheel brake

77

wheel brake

78

wheel brake

79

pressure sensor

80

isolation valve

81

isolation valve

82

intake valve

83

intake valve

84

intake valve

85

intake valve

86

outlet valve

87

outlet valve

88

outlet valve

89

outlet valve

90

Return line

91

Return line

92

Low-pressure accumulator

93

Low-pressure accumulator

94

Pressure fluid supply device

95

Pressure fluid supply device

96

pressure channel

97

pressure channel

98

junction

99

junction

100

switching valve

101

switching valve

102

master cylinder

103

casing

104

longitudinal bore

105

piston

106

piston

107

central valve

108

central valve

109

pressure chamber

110

pressure chamber

111

connection

112

connection

113

running channel

114

running channel

115

supply chamber

116

supply chamber

117

Primary cup seal

118

Primary cup seal

119

Secondary cup seal

120

groove

121

sealing arrangement

122

recess

123

disc

125

fuse element

126

guide ring

127

Secondary cup seal

128

attack

129

attack

130

recess

131

recess

132

housing bore

133

Return spring

134

Return spring

135

The End

136

The End

137

shell

138

shell

139

The End

140

The End

141

shell

142

caseback

143

piston section

144

piston section

145

Cage

146

pushrod

147

piston section

148

attack

149

attack

150

magnet

151

sensor element

152

disc

153

disc

154

carrier

155

tape

156

attack

157

spring means

164

shell

165

carrier

166

spring means

167

section

168

section

169

head Start

170

recess

171

Federation

172

The End

173

The End

174

inside

175

recess

176

recess

177

spring sleeve

178

magnet sleeve

179

section

180

Federation

181

head Start

182

section

183

Federation

184

head Start

185

head Start

186

edge

187

shell

188

carrier

189

spring means

190

section

191

section

192

Federation

193

recess

194

section

195

Federation

196

head Start

197

head Start

198

web

199

inside

200

paragraph

A

operating direction

Claims (26)

Device for monitoring the position and movement of a brake pedal, comprising a master cylinder ( 1 ; 102 ) with integrated position transmitter for monitoring the position of a sliding piston ( 2 . 3 ; 105 . 106 ) inside a housing ( 6 ; 103 ) for use within a controlled braking system for motor vehicles, in particular with driving dynamics control, the position transmitter using a magnet ( 35 ; 150 ) as a signal generator, which has a magnetic field in the direction of a sensor element ( 36 ; 151 ) that is fixed to the housing ( 6 ; 103 ) is arranged, and can be connected to an electronic control unit, characterized in that the magnet ( 35 ; 150 ) between two pistons ( 2 . 3 ; 105 . 106 ) arranged, and relative to at least one of the pistons ( 2 . 3 ; 105 . 106 ) is slidably provided. Device according to claim 1, characterized ge indicates that at least two spring means are provided with which the magnet ( 35 ; 150 ) between the pistons ( 2 . 3 ; 105 . 106 ) and at least one of the pistons ( 2 . 3 ; 105 . 106 ) is arranged to be relatively displaceable. Apparatus according to claim 2, characterized in that the spring means on the first piston ( 2 ; 105 ) supported return spring ( 14 ; 133 ) and one on the magnet ( 35 ; 150 ) supported additional spring means ( 42 ; 157 ; 166 ; 189 ), the further spring means ( 42 ; 157 ; 166 ; 189 ) has greater flexibility than the return spring ( 14 ; 133 ). Device according to claim 3, characterized in that the sensor element ( 36 ; 151 ) has at least one Hall sensor. Device according to claim 3 or 4, characterized in that the piston ( 3 ; 106 ) Means for guiding the magnet ( 35 ; 150 ) having. Apparatus according to claim 5, characterized in that the piston ( 3 ; 106 ) for guiding the magnet ( 35 ; 150 ) a peg-shaped piston section ( 34 ; 147 ) having. Apparatus according to claim 6, characterized in that between the magnet ( 35 ; 150 ) and the piston section ( 34 ; 147 ) A carrier ( 39 ; 50 ; 154 ; 165 ) made of non-magnetic material, and that the magnet ( 35 ; 150 ) in the axial direction between discs ( 37 . 38 ; 152 . 153 ) is arranged from an iron material. Apparatus according to claim 7, characterized in that the carrier ( 39 ; 50 ; 154 ; 165 ) is in one piece and essentially cylindrical. Apparatus according to claim 8, characterized in that the carrier ( 39 ; 154 ) a covenant ( 40 ; 155 ) for axial contact of the magnet ( 35 ; 150 ) and on the piston section ( 34 . 147 ) an attack ( 41 ; 156 ) to limit the relative displacement of the beam ( 39 ; 154 ) with respect to the piston ( 3 ; 106 ) is provided, the further spring means ( 42 ; 157 ) on the piston ( 3 ; 106 ) is supported. Apparatus according to claim 9, characterized in that the return spring ( 14 ) at least partially within a pot-shaped wall ( 24 ) of the piston ( 2 ) is arranged, and in the middle of a pin ( 26 ) with a stop ( 30 ) is protruded on which a sleeve ( 22 ) is set in such a way that when the piston is actuated ( 2 ) the means for guiding the magnet ( 35 ) axially and telescopically inside the sleeve ( 22 ) immersed. Apparatus according to claim 8, characterized in that the carrier ( 165 ) a first cylindrical section ( 167 ) and a second cylindrical section ( 168 ), the magnet ( 150 ) on the second cylindrical section ( 168 ) of the carrier ( 165 ) is arranged and the carrier ( 165 ) with its second cylindrical section ( 168 ) on the piston section ( 147 ) of the second piston ( 106 ) is performed. Device according to claim 11, characterized in that the carrier ( 165 ) radially inward projections ( 169 ), which is used to guide and prevent rotation of the carrier ( 165 ) on the piston section ( 147 ) in recesses ( 170 ) of the second piston section ( 147 ) intervene. Apparatus according to claim 7, characterized in that the carrier ( 165 ) is designed in several parts and a spring sleeve ( 177 ) and a magnetic sleeve ( 178 ), whereby on the spring sleeve ( 177 ) radially outward projections ( 181 ) are provided, which are for connection to the magnetic sleeve ( 178 ) between radially inward projections ( 184 . 185 ) the magnetic sleeve ( 178 ) are arranged, the projections ( 181 . 184 . 185 ) to guide and prevent rotation of the carrier ( 165 ) on the piston section ( 147 ) in recesses ( 170 ) of the second piston section ( 147 ) intervene and the magnet ( 150 ) on the magnetic sleeve ( 178 ) is arranged. Device according to one of claims 3 to 13, characterized in that the return spring ( 14 ; 133 ) and the other spring means ( 42 ; 166 ; 189 ) using a cage ( 51 ; 145 ) are so elastically pre-tensioned that an actuation shift of the piston ( 2 ; 105 ) compression of the return spring ( 14 ; 133 ) and an expansion of the further spring means ( 42 ; 166 ; 189 ) enables a proportional relative displacement of the magnet ( 35 ; 150 ) with respect to the piston ( 2 ; 105 ) to allow. Device according to claim 14, characterized in that the cage ( 51 ) a sleeve for storing the magnet ( 35 ) and a spring that is arranged to be displaceable to a limited extent and by a return spring ( 14 ) and spring means ( 42 ) loaded spring mount ( 52 ) which, when the piston is actuated ( 2 ) to the piston ( 3 ) that the sleeve and magnet ( 35 ) with expansion of the spring means ( 42 ) relative to the piston ( 3 ) in the direction of actuation (A). Device according to claim 14, characterized in that the cage ( 145 ) a first sleeve ( 137 ) and a second sleeve ( 164 ; 187 ) for preloading the return spring ( 133 ) as well as a carrier ( 165 ; 188 ), with an actuation shift of the piston ( 105 ) the magnet ( 150 ) with expansion of the further spring means ( 166 ; 189 ) relative to the piston ( 106 ) is moved in the actuation direction (A). Device according to claim 16, characterized in that the magnet ( 150 ) on the second sleeve ( 187 ) is arranged and the carrier ( 188 ) radially outward projections ( 196 ), which in recesses ( 193 ) the second sleeve ( 187 ) are performed. Device according to claim 17, characterized in that the magnet ( 150 ) in the axial direction between discs ( 152 . 153 ) made of an iron material, which has radially inward projections ( 197 ) and bridges ( 198 ) which are in the recesses ( 193 ) the second sleeve ( 187 ) are performed. Device according to claim 18, characterized in that the second sleeve ( 187 ) on the inside ( 199 ) a paragraph ( 200 ) and the further spring means ( 189 ) between paragraph ( 200 ) and the disc ( 153 ) is arranged biased. Device according to claim 18, characterized in that another spring means between the first sleeve and the carrier is arranged biased. Device according to one of the preceding claims 1-20, characterized in that the sensor element ( 36 ; 151 ) in one recording ( 60 ) is arranged, which in a defined position on the housing ( 6 ; 103 ) can be fixed. Device according to claim 21, characterized in that the sensor element ( 36 ; 151 ) together with rigid conductor elements in a form-fitting manner ( 60 ) and that an electrical connection line ( 61 ) into a plug device ( 62 ) the recording ( 60 ) can be inserted. Device according to claim 21 or 22, characterized in that the receptacle ( 60 ) in the direction of actuation (A) of the piston ( 2 . 3 ; 105 . 106 ) and relative to the housing ( 6 ; 103 ) is adjustable and fixable in a defined position. Device according to one of claims 21, 22 or 23, characterized in that the housing ( 6 ; 103 ) a stop ( 63 ) for receiving ( 60 ) and that between the stop ( 63 ) and recording ( 60 ) at least one spacer element ( 64 ) for a defined placement of the sensor element ( 36 ) is arranged. Device according to one or more of the preceding claims 21-24, characterized in that the exception ( 60 ) between two pressure medium tank connections ( 65 . 66 ) is arranged. Device according to one or more of the preceding claims 21-25, characterized in that the receptacle ( 60 ) is provided at one end of the housing.