DE10123730A1 - System for reliably transmitting control element position transmits position signal over several signal channels, at least one with lower positional resolution - Google Patents

Abstract

The system transmits actuating element position signals to a processing unit (14) via electrical signal lines. The position signal is transmitted over several signal channels (A',B',C'). At least one of the signal channels has a lower positional resolution than the other signal channels. Independent claims are also included for the following: a position sensor, a position signal receiver and a use of the system in a motor vehicle braking system.

Description

The invention relates to a system for secure transmission the position of an actuator on an electronic Processing unit via electrical signal lines, one Position transmitter for sending position signals according to Ober Concept of claim 10, a receiving device for Emp catch one over one or more electrical wires transmitted position signal according to the preamble of claim 14 and the use of such a system in a Motor vehicle brake system in which the position signals of a Brake pedals mainly by means of electrical signals to a Brake control device are transmitted.

Today's motor vehicles are mostly with braking systems equipped in which a transmission of the brake pedal pressure to the brake cylinders - usually from a brake booster reinforced - via hydraulic lines.

In next generation automobiles, one Brake request from the driver the movement signal of the brake signal generator no longer exclusively hydraulically to one Brake control device (hydraulic or electric) transmitted, but by means of electrical lines (x-by-  wire). With the electrohydraulic brake (EMS), in addition an electrical signal transmission for emergency operation between brake pedal and brake control unit in addition to electrical line, a hydraulic line can be provided.

The functional reliability of a motor vehicle brake system very high demands are made. Therefore also the electronic detection of the position of a brake signal done very precisely and reliably.

An electronic system for recording the position of a Brake signal generator must also have a low quiescent current need so that the usually limited energy capacity of an energy storage device in the motor vehicle is not is overburdened. Furthermore, one must correspond have the system activated quickly and reliably, if a brake pressure request by moving the brake signal takes place or other external events like that Starting the engine on an upcoming brake pressure request close.

There are already systems for transmitting a brake signal known, in which potentiometers for recording the absolute Position of the brake pedal can be used and a transfer supply the position signal analog to a processing unit done analogously. These systems show, among other things, the after on that they are particularly sensitive to interference are. Furthermore, the transmitted position signals are on due to hysteresis and wear of the potentiometer contacts not sufficiently accurate or permanently available.  

In addition to the passive ones described above Systems active systems for distance measurement known that stale are technically considerably more complex, and as a result a quiescent current consumption that is too high for continuous operation point.

The invention therefore suggests a comparison with known systems improved system for transmitting a brake signal.

The invention relates to a system for secure transmission the position of an actuator on an electronic Processing unit, the processing unit in particular special in a brake control device (ECU) inte is griert, over electrical signal lines, in which the Position signal over several signal channels, preferably co dated, transmitted.

The system according to the invention has to increase the loading drive safety two or more channels. Especially before The system is designed with three channels. To one the channels are largely independent expediently also the chip assigned to the channels Power supplies designed independently. Through the redundant The design of important system functions becomes clear Increased reliability achieved.

The signals are transmitted via electrical signals lines that are divided into several signal channels. The term "electrical signal lines" is used in addition to Electric lines also wireless known per se understood for the transmission of electrical signals,  such as B. modern bus systems based on blue tooth technology etc. Also the term signal lines are used summarizes the signals optically, e.g. B. over glass fibers, over wear.

According to a preferred embodiment, at least one Signal channel a lower spatial resolution than that other signal channels. The channel with the lower place Resolution can be done this way with a lower current be operated continuously.

In the system according to the invention, preferably the over the signal lines transmitted signals by means of a white ter generated position encoder described below. The one from the bottom signals generated by the position transmitter are then even if receiving device described below received gene.

Preferably, the system is designed so that this under can assume different operating states. The Betriebszu stands differ by a different Energy consumption from each other. Particularly preferred under the operating states differ in that the clock rate a filter element at the input of the receiving circuit is different.

In a preferred embodiment of the invention that is System equipped with an alarm function. An activation of the system or parts of the system can either by a permissible wake-up signal in the first channel, such as a rectangular pulse from the position encoder, or by other Er  events such as ignition, central unlocking, door opener etc. respectively. The system is before receiving a wake-up signal in a state with low energy consumption. In this The condition is only individual or all functional groups of a first channel active or limited active. These functional groups in the state with low energy consumption custom have wake-up agents with which some or all Function groups of additional channels in a state with high Rem energy consumption can be offset, in particular special the full functionality of the entire device represents is. The alarm function enables continuous operation of the Circuit arrangement in a sleeping mode ("sleep mode ") with low energy consumption and simultaneous Ak Activation ("wake-up") of additional channels with comparatively se higher resolution. In addition, the required redundancy of the system. It can be particularly useful to channel the alarm function with a two-stage wake-up agent equip, after receiving any signal first a first stage in the switching of the alarm is activated, which is a preliminary check on a permissible wake-up signal. This can e.g. B. a simple che comparator circuit, the signal level with a permissible threshold voltage is compared and if exceeded the second stage switches on.

In the second stage of the wake-up agent, a further, more precise verification of the admissibility of the received Si gnals performed, for example by means of a digital Filter. Another example of a two tier scarf The wake-up arrangement arrives on the same day German patent application P. , , , , , , , , (Applicant:  Continental Teves AG & Co. oHG, title: "Process and scarf arrangement for activating deactivated circuit modules and their use ", file number not yet knows).

According to the invention, preferably only one channel with Mit to wake up another channel or channels fitted.

In a preferred development of the system, an ins special monitoring arranged on the receiving device Chungs circuit provided which selected some Sy system functions are monitored and dependent on the result monitoring an emergency operation or a shutdown of the Systems evokes.

The output stages of the position transmitter and are preferably the input stages of the receiving device with respect to a common current / voltage supply ratiometrically set up builds.

Under the term "ratiometric" in the sense of the Erfin understood that at the output of a channel of power driver stage in the position transmitter the voltage level to the pe gel is adapted to the voltage supply. This changes the output voltage or the output level of the channel to change the supply voltage in the same ver ratio (linear).

The input stages of the Ka channels are also set up in such a way that they Sensitivity in the same ratio as the supply behave tension. This can result in the operation of Positi  onsender and receiving device with the same voltage supply can be avoided by different Voltage level caused level fluctuations in the signal to a misinterpretation in the comparator of the reception scarf lead. Of course, the above can be written ratiometry only within a suitable ver comply with the supply voltage range.

In a preferred development of the system, it is provided hen that existing in the channels of the position sensor Function groups of one each from the receiving device tion-fed power / voltage supply line become.

The invention also relates to a position transmitter for transmission of position signals over one or more channels according to Claim 10.

In the electronics of the position encoder, preference is given to generated signals by including a power supply educated. It is therefore an active position giver.

The displaceable magnetic encoder ( 1 ) present in the position encoder preferably has magnetic zones along the displacement direction which are of equal length.

The magnetic transducers for sensing the magnetic field (e.g. AMR Bridge circuits) insert the magnetic field information into electrical signal around. It is for redundancy reasons useful if several sensor modules consisting of Ma gnet converter and signal conditioning circuit provided  are. There is preferably exactly one in each sensor module Magnetic converter provided, this if it is egg NEN converter that works according to the AMR principle contains for example two or more bridge circuits. The electronic signal processing is in the sensor module tion circuit at least partially with the converter element in integrated into a common housing. However, is preferred the entire signal processing circuit in the sensor construction group integrated.

In a further preferred embodiment, the Ma converter of all channels and the assigned preparation circuits integrated in a sensor module. Very special the processing circuits are preferred on one integrated chip.

The generated by means of the position sensor according to the invention Signals are preferably pulse encoded. It can be different like pulse types are provided. Is particularly preferred the amplitude and pulse width in each pulse type placed. The pulse types preferably differ in their amplitude. By using two types of pulses can an additional signal line for the transmission of a Direction of movement signal can be saved.

A pulse is expediently generated by the signal processing tion circuit generated when the position of the loading actuating element by the width of a zone of the encoder ver has changed. This results in a smaller pulse stood with increasing movement speed of the actuator supply elements.  

The invention also relates to a receiving device for Receiving one over one or more electrical lines transmitted position signal, in particular signals ei Nes position encoder described above according to claim 14th

In the processing channels of the receiving device preferably counter for counting over the line over portable signal pulses available, especially each Channel is equipped with exactly one counter.

At least one Im connected to the counters is preferred Pulse differentiation device available, so that the counter be counted upwards or downwards if pulses of one first type are received and the counters down respec tive to be counted up when pulses of a second Variety to be received.

In a preferred development of the receiving device is a suppressor for suppressing Interference signals fed in via the signal input (s) provided in one or preferably in all channels. The Suppression device expediently comprises transmitters a current driver on the side or on the receiver side, the signal line of the respective channel is constantly flowing eats current. In the receiving device (or al alternatively on the transmitter side) this current is generated by means of a ge suitable low-impedance line terminated again. A current sink in is preferably used to discharge the current the circuit of the receiver used. Furthermore is preferably a signal filter for each channel in the receiver  with which interference signals are filtered out of the data signal can be tert. It is preferably the Si gnalfilter around a digital filter.

In principle, every channel can be included in the receiving device be equipped with its own current / voltage supply. According to the invention, however, it is preferred that the voltage supplies for the individual channels in the receiving circuit are summarized in a separate area and these are independent of the channels. It is appropriate that the Voltage supply has channels that can be activated per channel, that are independent of each other.

In the receiving circuit according to the invention, each Ka nal position information about the position of the Positi onsender saved. Different position information NEN can be caused, for example, by interference pulses mistakenly identified as valid increment pulses are. Diverge the individual position information from each other from, there is an error. Such a fault condition deriving from different meter readings can be from a circuit of the control device (e.g. ASIC or discrete Circuit) or by means of a suitable diagnostic routine (e.g. implemented in a microcomputer that under the channels Consideration of different resolutions, if applicable same) can be determined.

To eliminate these errors is another before preferred embodiment of the receiving circuit a Rekali Brierungseinrichtung provided with which in the Channels differently recognized position an alignment of the stored position information  can. This is for example by resetting everyone Counter to a new common value (reset or start worth) possible.

Preferably, errors are made in the recalibration device counted pulses at each zero point crossing (complete Relief of the brake pedal) eliminated. This is possible because the position of the actuating element usually in the unconfirmed in a more or less precisely defined state Starting position returns. A negative position can therefore be excluded.

It is also possible to calibrate errors in Rich tion of the maximum actuation of the actuating element men. There is an additional absolute position signal for this encoder required.

An intelligent recalibria is particularly preferred process in the microcomputer of the receiving circuit leads, in which the time course of the pedal position, ins especially the current driving situation of the vehicle velvet, is evaluated. For example, it can be evaluated whether a constant position of the brake pedal over a certain time is present, so that it can be assumed that the brake is not operated. You can also query whether the accelerator pedal is actuated in the motor vehicle, which also indicates that the brake pedal is not being used.

Finally, the invention further relates to the use of the System according to the invention described above in one force Vehicle brake system in which the position signals of a Brake pedals mainly by means of electrical signals to a Brake control device are transmitted (e.g. Elek trohydraulic brake or electromechanical brake).  

Further advantageous embodiments of the invention result from the following description of the figures and the Un dependent claims.

Show it

Fig. 1 is a schematic representation of the inventive system SEN,

Fig. 2 shows a position indicator according to the invention,

Fig. 3 shows a further position detector according to the invention,

Fig. 4 is an example of a transmission protocol for transmission of the position signal from a positi onsgeber to a receiving device,

Fig. 5 shows an example of an integrated circuit for a position transmitter and an integrated circuit device for a receiving device, and

Fig. 6 is a time-dependent representation of waveforms during the change of the system from a resting state with low power consumption to a woken system state with higher Stromver consumption.

The basic functional blocks of the system according to the invention are described with reference to FIG. 1.

To transmit the position signals from the position sensors for brake pedal sensors shown in FIGS. 3 and 4, two, in particular three, essentially completely independent signal channels A, B, C, each with a signal line 7 , 8 , 9, are used. The channel A 'assigned to the sensor channel A in the receiving circuit 14 is designed for operation with a comparatively low power consumption and is in permanent operation. In the sleeping state, the other channels are deactivated, ie their voltage supply is switched off. If a valid signal for waking up is recognized in channel A ', the wake-up device 46 activates the other channels B' and C 'via line 38 , as well as microcomputer 18 and a monitoring circuit (fail-safe logic), which implement certain error monitoring measures, such as monitoring the counter readings of the position counters for a maximum deviation and monitoring of overvoltages and undervoltages.

The distance traveled by the brake pedal is determined by three independent sensor modules 2 . Each sensor module independently generates pulses depending on the defined steps of a jointly scanned encoder 1 ( FIGS. 2 and 3). Depending on the direction of movement of the pedal 6 bezüg Lich the direction of movement distinguishable rectangular pulses are transmitted via the lines 7 , 8 , 9 .

On the chip 14 , the pulses are decoded channel by channel and passed to counters 15 , 16 , 17 , which count up or down depending on the direction of movement. The counters then save the current position of the brake pedal and hold this information ready for further processing by the microcomputer 18 .

It is preferred that the components of the receiving devices are integrated on a common chip 14 .

A lower power consumption of channel A 'can be achieved by designing the channel in question with a lower spatial resolution. Counter 15 then counts coarser position changes than the other counters 16 and 17 .

The principle of generating the position signals is shown schematically in FIG . By means of a brake pedal 6 , a magnetic encoder 1 is moved relative to the sensor module 2 via a push rod.

The converter 3 arranged in the sensor assembly for converting the magnetic signal into an electrical signal can operate, for example, according to the AMR principle, the GMR principle or the Hall principle. The sensor modules 2 are arranged to the encoder so that each sensor module either faces a different sequence of periodically changing magnetizations from different encoders or all sensor modules sample the same sequence of periodically changing magnetizations of a common encoder. According to the invention, a permanent magnetic encoder with a tubular design is preferably used. The sequence of changing magnetization is generated by zones 10 (north / south poles) which are magnetized in an alternating direction and which run as equidistant ring zones 10 along the tube jacket. An example of a mechanical device which can preferably be used according to the invention for determining the pedal path with one or more encoders and magnetic transducers is described in German patent application P 100 10 042.2 (Continen tal Teves). Depending on the extent of the evaluation of the use of the magnetic field lines generated by the encoder, displacement sensors can be produced in a manner known per se, which provide an output signal with different spatial resolution from the magnetic field signal by means of evaluation electronics.

The transducer elements 3 are preferably sensor elements based on AMR bridges with in particular two bridge circuits in one transducer. The converters 3 are connected via four lines to a signal conditioning circuit 4 . The interpolator unit 4 generates two square wave signals shifted by a angle of 90 °, which are transferred to the function unit 5 . The signal conditioning circuit is a suitable integrated analog signal sequence circuit with an interpolation network, which provides the movement information depending on the direction of movement via two separate lines. The electronic functional unit 5 generates from the square wave signals of the interpolator unit 4 an incremental signal pulse sequence in succession of the location increments, with the special feature that the two directions of movement are characterized by using two different signal amplitudes. The sensor modules 2 transmit the information about the direction of movement as part of the signal of the local increments via line 7 , 36 and 21 being connections for the supply voltage and 37 being provided for connecting the ground. The integrated circuits 4 , 5 and the converter 3 are combined in a common housing 39 .

In contrast to Fig. 2, in which the sensor assembly 2 is designed so that the transducer 3 with the electronic signal processing circuit from interpolator unit 4 and functional unit 5 are combined into a common integrated circuit device 42 , in the example of Fig. 3, the converter 3 and the interpolator unit 4 are housed in a common housing 39 '. The functional unit 5 is executed separately from the arrangement in the housing 39 '. The separate arrangement of functional unit 5 results in cost advantages, since the unit combined in housing 39 'in the same embodiment can also be used as wheel speed sensors for electronic brake systems.

In FIG. 4, an example of a signal with a transmission protocol Übertra is specified for transmission of the position signal from egg nem position sensor to a receiving device. The movement of the encoder in a first direction 11 ( FIG. 2) leads to the generation of rectangular pulses 12 with an amplitude of 4 V. Each pulse corresponds to a movement of the encoder 1 around a zone 10 . When moving in the second direction 25 , rectangular pulses with an amplitude of 2 V are generated. Between the pulses there is an offset voltage of U _offset = 1 V for the detection of sensor errors and line errors (e.g. cable break), which can be generated with an offset device provided in the circuit. By defining the interface with comparatively high signal levels in the range of a voltage of 1 to 4 V, the sensitivity to errors in signal transmission can be reduced.

It makes sense to use the width of the generated impulses Circuit set in such a way that the maximum possible pedal travel speed, which is determined by the mechani cal inertia of the position sensor device be up is limited, can still be transmitted reliably. purpose moderately the pulse width is chosen so that the Ver Ratio of pulse width to pulse pause width (duty cycle) at the maximum possible pedal speed be about 50% wearing.

In Fig. 5, the block diagram of an integrated circuit device 13 of a position transmitter and an integrated circuit device 14 for receiving the signals of the position transmitter is shown. It is expedient that the receiver circuit is grated in a chip of an electronic brake control unit inte fourteenth

The position sensor 13 comprises for each channel a Wandlerele element 3 with a magnetoresistive bridge circuit, an increment generation logic 49 and a line driver stage 50 .

The pulses of the position encoder are passed in parallel in channels A, B and C via lines 7 , 8 and 9 to the receiving circuit 14 . The power supply of the position sensor takes place through the receiving device, preferably for each channel separately via a channel-wise assigned power supply line 21 , 22 and 23 . Channel A of the position sensor is designed so that the pulses generated in this channel are generated with a lower loci solution than channels B and C. For this purpose, what is preferred according to the invention, a specially provided output of the signal processing circuit in the sensor module with a defined lower resolution can be used. Suitable displacement sensors with different resolutions are described in German patent application P 100 10 042.2 (Continental Teves) mentioned above.

Channel A of the position transmitter is active both when the system is asleep and when it is activated. The channels B and C are switched on when activated by channel A via the power supply 47 of the receiving circuit.

In the channels of the receiving circuit, the signals are supplied on the output side to a comparator stage 27 , 28 , 29 for differentiating the signal levels.

By means of an offset device for interference suppression, an offset current with power drivers 50 and current sensors 30 , 31 , 32 is impressed on the signal lines, optionally together with an offset voltage, the current sink in channel A 'being able to be switched off in the sleeping mode via switch 41 .

In the sleeping mode, especially if the ignition has not been operated and there is no brake pedal actuation, channel M of the receiving circuit is only active to a limited extent. The further channels B 'and C' are deactivated by switching off the power supply. The deactivation or activation of the channels B and C of the position transmitter is carried out via the power supply lines 22 and 23 .

With the at the output of the digital filters 33 , 34 and 35 arranged counters 15 , 16 and 17 , the number of pulses detected via the line is counted, the counters depending on the signal type "forward" (pulse shape 12 ) or "reverse" (pulse shape 26 ) either counted up or down.

To detect errors during data transmission, an error detection circuit 24 is arranged in the receiving circuit, which is connected to the counters 15 , 16 , 17 and the microcomputer 18 . Fault monitoring can preferably be carried out by monitoring the counter readings for a certain maximum permissible difference of, for example, a few bits. In an embodiment with 3 or more channels, the channel with a counter reading that differs from the other channels can be excluded from the position determination. Due to the design with at least two high-resolution channels, at least one high-resolution channel is advantageously always available in the event of such an error, provided that there is no rare double error.

The error detection circuit is additionally preferred equipped with undervoltage and overvoltage detection. This allows errors such as cable breaks and faulty Trei Level in the sensor, etc., which lead to undervoltage can and errors, such as short circuits against the battery or the supply voltage etc. which lead to an overvoltage can recognize.

To reduce the sensitivity to signal interference, the reference potential in each channel is routed in parallel to the signal lines via an additional line (not shown) to the receiving circuit. Since in this case coupled interference essentially equally on the lines for the reference potential and the signal auftei len (common mode interference), these can be filtered out in the input stage of the receiving circuit by means of a differential input stage 43 , 44 , 45 provided for each channel.

In the sleeping mode, the input comparator 27 , the digital filter 33 , the counter 15 and the alarm device 46 are switched on. To switch the input circuit from the sleeping mode to the fully activated operating mode (wa ke-up), in which in particular the current source of the wake-up channel, the error detection circuit 24 and the microcomputer 18 are switched on, the input signal is switched on in channel A by the alarm device 46 monitors for a signal pulse. For this purpose, channel A is connected to the power supply 47 in both operating states. Low power consumption is achieved by slowing the clocking of the digital input filter 33 .

But it is also possible to design the circuit so that the digital filter is switched off in sleeping mode. This is preferred for reasons of simplicity, if the on-delay of the digital filter is so low is that the remaining time to recognize a just received signal pulse at which the digital fil ter is running, it is enough to un a pulse of an interference signal differ. It is special for this embodiment expedient if the two-stage described above Alarm clock is used.

In the first-mentioned embodiment with frequency switching of the digital filter, the reduced clocking in sleeping mode results in a significantly reduced spatial resolution. However, this is still sufficient to detect an event. The one or more channels B 'and C' have a higher spatial resolution due to the higher timing of the digital filters 34 and 35 , but these are only active in the activated operating mode. If the alarm device 46 detects a signal that is permissible for waking, the high-resolution channels are activated by switching on the power source channels 48 provided for the channels in the power supply 47 . In addition to activating channels B 'and C', the power source of channel A 'is also switched on. The alarm device is particularly preferably also activated the control unit for the brake system.

The receiving circuit further comprises a circuit module connected to the counters 15 , 16 and 17 for determining the pedal acceleration in real time (timer input capture), which can be read out by the microcomputer 18 .

A valid wake-up signal, which the wake-up device to the Ak tivieren the channels B 'and C' may have due of the activation process is no longer full are constantly processed in channels B 'and C'. here by results in a in the counters of channels B 'and C. Uncertainty regarding the starting position of the brake pedal. However, this is not greater than the spatial resolution the pulse detection in channel A, A '.

The system described here with only two channels represents a more economical embodiment in comparison to the system with three channels shown in FIG high-resolution switched off the channel that can be awakened by the first channel. In the two-channel system, error monitoring is also possible, but this is limited when comparing the position counter readings to the bits available to the low-resolution counter in the first channel. Accordingly, an error is detected later than in a system with 3 or more channels. If there is a difference in the meter readings in the two-channel system described here, the brake system - if it is an electro-hydraulic brake - is switched to hydraulic emergency braking mode. It is also possible e.g. B. when using the system in brake systems without hydraulic emergency braking operation, an emergency operation without redundancy with only one sensor to maintain. A corresponding emergency operation is also possible with an exclusively correctly working low-resolution channel, but then a requirement of the braking effect is only in comparatively rough levels possible.

In Fig. 6, the temporal sequence of the signals in the receiving circuit of Fig. 5 is shown, which is generated after the arrival of a valid wake-up pulse 51 in channel A '. With further movement of the pedal transmitter, further pulses 52 and 53 follow on the signal line from channel A '. The counter 15 assigned to channel A '( FIG. 5) is permanently switched on, so that it reflects the current position of the brake pedal in the lower spatial resolution. After a wake-up pulse in channel A or an external wake-up signal, the receiving circuit is switched from sleeping to active mode by setting the wake-up signal 54 to "high". Signal 54 activates the voltage supply on the receiving circuit and the control unit. After three successive sampling cycles 58 in the digital filter 33 ( FIG. 5), the pulse 51 is recognized as a valid wake-up signal. As soon as the voltage supply is ready after a period 55 , the RESET signal 56 is set from "high" to "low". With this signal, the sampling rate in filter 33 is increased from 6 kHz to 300 kHz. This frequency increase is indicated by a transition to "high" by means of signal 57 . The pulses 60 in channels B 'and C' are narrower because these channels have a higher resolution than channel A '. Then the value from the counter 15 of channel A 'is entered in the corresponding high-order bits (MSBs) of the counters 16 , 17 in channels B' and C '. After the transfer of the counter readings, the counters 16 , 17 must not begin to count immediately, via the brake pedal being located at an undetermined position between two placemarks of the counter 13 due to the filter time. Due to the fact that the position of the brake pedal is only precisely determined at the time at which a pulse edge from counter 15 is present, counters 16 and 17 are only started when a RESET edge on signal 55 has occurred and in channel A. an edge of a pulse 52 following the wake-up pulse 51 is registered.

As already explained above, the lower clock leads the filter in channel A 'in sleeping mode to a ver reduced power consumption. A detection of a wake-up pulse is possible with the low clock because of the pulses and pauses times of the signals generated by the position transmitter in channel A.  are longer than in channels B 'and C'. In operation at fully activated receiving device, however, the clock of the Ab Scanning frequency in channel A 'to the clock of channels B' and C be raised so that no runtime differences in the Triggering of the counters occur which are too different Counter readings would lead.

Claims (18)

1. System for the safe transmission of the position of an actuating element ( 6 ) to an electronic processing unit ( 14 ) via electrical signal lines ( 7 , 8 , 9 ), characterized in that the position signal via a plurality of signal channels (A, A ', B, B ', C, C') is transmitted. 2. System according to claim 1, characterized in that at least one signal channel (A, A ') has a lower location solution, as the other signal channel or channels (B, B ', C'). 3. System according to claim 1 or 2, characterized in that the signals transmitted via the signal lines are generated by a position transmitter ( 13 ) according to one of claims 10 to 13 and these signals with a receiving device ( 14 ) according to one of claims 14 to 17 be received. 4. System according to at least one of claims 1 to 3, because characterized in that the system is different Can assume operating states, the Be drive states through a different energy distribution differentiate from each other. 5. System according to claim 4, characterized in that an individual ( 15 , 46 ) or all function groups of a first channel (A ') are active or limitedly active in the state with lower energy consumption, and these function groups with low energy consumption alarm means ( 46 , 38 ) with which individual or all function groups of further channels (B ', C) can be put into a state with higher energy consumption. 6. System according to at least one of claims 1 to 5, characterized in that the system comprises a monitoring circuit ( 24 ) which is arranged in particular on the receiving device ( 14 ) which monitors some selected system functions and depending on the result the monitoring causes an emergency operation or a shutdown of the system. 7. System according to at least one of claims 1 to 6, there characterized in that the output stages of the positi onsgebers and the input stages of the receiving device regarding a common current / voltage supply are ratiometric to each other. 8. System according to at least one of claims 1 to 7, characterized in that the function groups provided in the channels of the position sensor ( 3 , 43 , 50 ) each have a current / voltage supply line ( 21 , 22 , 23 ) fed by the receiving device ) are fed. 9. System according to at least one of claims 1 to 8, characterized in that one or more Offsetein devices ( 30 , 31 , 32 , 50 ) is present with which an offset level of a current and / or egg ner voltage to the signal line Detection of sensor errors or signal line errors and / or for filtering signal interference can be impressed. 10. Position transmitter for sending position signals via egg nen or more channels (A, B, C), with at least one of an actuating element ( 6 ) relative to one or more magnetic transducers ( 3 ) displaceable magnetic encoder ( 1 ), the encoder along the direction of displacement has magnetic zones ( 10 ), characterized in that the magnetic transducer (s) are arranged together with a fully or partially integrated electronic signal processing circuit ( 4 , 5 ) in an electronic sensor module ( 2 , 40 ) and the signal processing circuit as a function of the position of the actuating element coded signals ( 12 , 26 ) on one or more electrical signal lines ( 7 , 8 , 9 ) provides. 11. Position transmitter according to claim 10, characterized in that the signals ( 12 , 26 ) are pulse coded. 12. Position sensor according to claim 11, characterized in that a pulse is generated when the position of the actuating element has changed according to the width of a zone ( 10 ) of the encoder. 13. Position sensor according to claim 11 or 12, characterized in that with a movement of the actuating element in a first direction ( 11 ) pulses of a first type ( 12 ) are sent and with a movement of the encoder in a second direction ( 25 ) pulses of further sorts ( 26 ) are sent, the pulses of the individual varieties differing in their pulse shape. 14. Receiving device for receiving a via one or more electrical lines ( 7 , 8 , 9 ) transmitted position signal, in particular signals from a position transmitter ( 13 ) according to one of claims 9 to 13, characterized in that the receiving device has a plurality of processing channels ( A ', B', C ') each with signal inputs for processing one position signal each. 15. Receiving device according to claim 14, characterized in that in the processing channels in each case counters for counting signal pulses which can be transmitted via the line ( 15 , 16 , 17 ) are present. 16. Receiving device according to claim 15, characterized in that each channel has at least one pulse distinguishing device ( 27 , 28 , 29 ) connected to the counters, so that the counters are counted upwards or downwards when pulses of a first type ( 12 ) are received and the counters are counted downwards or upwards when pulses of a second type ( 26 ) are received. 17. Receiving device according to at least one of claims 14 to 16, characterized in that a two-stage wake-up circuit ( 46 ) is provided, which initially wakes the first stage of the wake-up device when a pulse is received, but not the second stage of the wake-up circuit ( 46 ) , and the first stage has means for preliminary evaluation of the input signal with regard to the detection of an input signal valid for waking and means for switching on the second stage when the first stage has recognized a valid pulse, and the second stage has means ( 33 ) with which a final check for a valid wake-up pulse can be made. 18. Use of the system according to one of claims 1 to 9 in a motor vehicle brake system in which the positions signals from a brake pedal predominantly by means of electri signals to a brake control device will wear.