Sensor device for determining a position state of a component of a vehicle part, control device, vehicle part, motor vehicle and method

Abstract

The invention relates to a sensor device (12) for determining a position state of a rotatably and / or longitudinally displaceably mounted component (5) for a vehicle part (2) of a motor vehicle (1), comprising at least one processing circuit (15) which is adapted to process the position state of the component (5), the at least one processing circuit (15) is adapted to generate at least one electrical sensor signal (17), which is dependent on the position state and has a sensor signal voltage, and to output the sensor signal via the at least one signal output (18), checking whether an error state related to the sensor device (12) exists, in which the generation of the at least one sensor signal (17) is interrupted, and in the event of the error state, generating at least one error signal (24) having an error signal voltage that differs from the at least one sensor signal voltage, the error signal is output via at least one signal output (18).

Description

Technical Field

[0001] The present invention relates to a sensor device for determining the position state of a component of a vehicle part for a motor vehicle that is supported so as to be rotatable and / or longitudinally displaceable, the sensor device comprising at least one processing circuit adapted to generate at least one electrical sensor signal having a sensor signal voltage that is dependent on the rotational position and to output the sensor signal via at least one signal output terminal. Background Art

[0002] Such sensor devices (which may also be referred to as position sensors) are used to determine the current position state of a component. This position state can be understood, for example, as the rotational position or rotor position of a rotatably supported component. Additionally or alternatively, the position state can be understood as the longitudinal position or axial displacement of a longitudinally displaceable component. A control signal is often generated based on the current position state, and this control signal is often used to control a vehicle component that includes the component.

[0003] For example, the rotational angle of a rotatably mounted component can be detected using a sensor device, where the corresponding angular information can form an input variable for regulating various parameters. One possible application example is a vehicle component configured as an electric motor, in which the rotor forms the rotatably mounted component, and the angular information serves, in particular, as an input variable for regulating the torque and speed of the electric motor. Another example of angular information is a vehicle component configured as a transmission, in which a drive shaft or a transmission gear constitutes the rotatably mounted component.

[0004] Additionally or alternatively, provision can be made for the current position or orientation of the component to be detected with the aid of a sensor device in relation to a longitudinal displacement. In this case, the component can be moved longitudinally, or in other words, linearly, along a particularly rectilinear movement path. Possible applications include situations in which a particularly elongated component is supported so that it can be axially displaced in its longitudinal direction. Specifically, this can involve, for example, a vehicle component configured as a transmission or clutch device.

[0005] Concepts for determining the rotational position of a rotatably mounted component of a vehicle part by means of sensors are known, for example, from DE 10 2010 038 770 A1, KR 10 2019 0 047 228 A and JP 2007-269 277 A. Summary of the Invention

[0006] The object of the present invention is to provide an improved concept for determining positional states of components of a vehicle part by means of sensors, in particular with regard to error states associated with the individual sensor devices.

[0007] According to the application, in a sensor device of the type mentioned at the outset, the object is achieved in that the at least one processing circuit is further adapted to check for the presence of an error state related to the sensor device, in which error state the generation of the at least one sensor signal is interrupted, to generate at least one error signal having an error signal voltage differing from the at least one sensor signal voltage in the event of the presence of an error state, and to output it via the at least one signal output.

[0008] The application is based, inter alia, on the idea that in the event of the presence of an error state related to the sensor device, i.e. in the event of an internal sensor error, the processing circuit also actively contributes to the signal output, so that the output error signal can be identified in further signal processing. This identifiability is achieved in that the sensor signal generated in the normal operating state and the error signal generated in the error state differ in their respective signal voltages. The output signal thus exists in the form of a voltage output via the signal output, in particular not being zero.

[0009] In particular, in the application it is avoided that in the error state a measurement voltage occurs which is related to the output signal, which can erroneously indicate the presence of a normal state and which can arise due to internal conditions of the control device connected to the sensor device. This disadvantage can occur, for example, if in the event of an error no specific error signal or specific output voltage is output via the signal output at the sensor device, but instead the signal output is switched to a high-impedance state.

[0010] Preferably, the processing circuit of the sensor device is an application-specific integrated circuit or "ASIC" for short, or, in general terms, a so-called application-specific standard product or "ASSP" for short. It is conceivable that one or more processing circuits are provided, via which the at least one output signal can be generated respectively. In particular, up to four signal outputs can be provided for each processing circuit. Preferably, two processing circuits are provided for each sensor device, wherein each of the processing circuits preferably comprises four signal outputs.

[0011] The sensor device according to the present invention preferably includes at least one sensor unit, by means of which at least one measurement signal related to the position state can be generated and output to at least one processing circuit, wherein the at least one processing circuit is adapted to generate at least one sensor signal from the at least one measurement signal. A sensor unit is to be understood as that part of the sensor device that implements the sensor. Thus, the sensor unit can generate at least one measurement signal, in particular also in the form of an electrical signal, which can be directly related to a measurement parameter to be measured. The measurement parameter is or relates to the position state. The processing circuit generates at least one sensor signal from the at least one measurement signal, which in turn relates to or describes the measurement parameter and, therefore, also the position state.

[0012] It is conceivable that at least one sensor unit forms an eddy current distance sensor. The operating principle of an eddy current distance sensor is based on the fact that changes in a magnetic field in a solid, blocky object made of an electrically conductive material induce eddy currents in the object. According to Lenz's law, the magnetic field generated by the eddy currents counteracts the causes of the eddy currents. For example, an eddy current distance sensor comprises a transmitter and a receiver, wherein the transmitter generates an alternating electromagnetic field that is received by the receiver. Depending on the distance between the device comprising the transmitter and receiver and the object being measured, a damping effect is produced that influences the alternating electromagnetic field, and a distance-dependent measurement signal can be determined based on this damping effect. It is also conceivable that the sensor unit comprises an electromagnetic field coil that is supplied with an alternating voltage, wherein the generated alternating field is again influenced by the distance from the object being measured. Specifically, the impedance of the field coil then changes depending on the distance, so that the measurement signal can be determined based on this impedance change.

[0013] In order to detect the rotational position using an eddy current distance sensor, the relative distance between the surface of the measurement object (i.e., in this case, the rotatably mounted component or a part connected thereto) and the eddy current distance sensor needs to change during rotation. To this end, an asymmetric element can be arranged on the rotatably mounted component, rotating together with the rotatably mounted component, thereby changing the distance between the surface of the asymmetric element and the eddy current distance sensor. It is conceivable that at least one sensor unit is arranged at an end face of the rotatably mounted component or its shaft, wherein a sensor wheel or impeller is arranged at the end face of the component or shaft as the asymmetric element. The sensor wheel / signal wheel or impeller can be a disk-shaped element with an asymmetric structure formed on the end face of the disk, for example, including or forming blades / wings, which achieves a distance that changes during rotation. The asymmetric element is made of an electrically conductive material, such as metal.

[0014] The at least one processing circuit can be adapted to generate the at least one sensor signal such that a sensor signal voltage of the at least one sensor signal varies periodically and within a normal operating voltage band, in particular sinusoidally, during a constant rotation of the rotatably supported component. It is conceivable that the current rotational position can be determined based on the phase of the periodically varying signal, for example, based on the zero crossing of a sine or cosine oscillation. Furthermore, the current rotational speed can be determined based on the period duration of the periodic sensor signal.

[0015] The at least one processing circuit can be adapted to generate the at least one error signal such that an error signal voltage of the at least one error signal is within at least one error operating voltage band, wherein the at least one error operating voltage band is located above or below the normal operating voltage band. It is conceivable to provide two error operating voltage bands, wherein an upper error operating voltage band is above the normal operating voltage band and a lower error operating voltage band is below the normal operating voltage band.

[0016] According to this embodiment, determining the voltage of each output signal can distinguish whether the output signal is a sensor signal or an error signal. Each voltage band can also be referred to as a voltage interval. The voltage band can be continuous or uninterrupted, and in particular, extends from a lower voltage value to an upper voltage value. Gaps can exist between the voltage bands. Preferably, the gaps are wide enough to ensure that the measured voltage value is not assigned to an incorrect voltage band due to measurement errors.

[0017] It is conceivable that at least one processing circuit can be adapted to determine at least one piece of error information related to the type or characteristics of the error state and to output at least one error signal such that the error signal voltage of the at least one error signal is correlated with the at least one piece of error information. According to this embodiment, the processing circuit not only detects the presence of an error state, but also determines error information specifically tailored to the characteristics of the respective error that is present. The error information determination by the processing circuit can be achieved by detecting a specific circumstance (e.g., a specific circumstance regarding the type or form of the measurement signal) that occurs in the event of a specific error, wherein the error signal and its voltage depend on this circumstance. This allows the presence of the respective error to be specifically taken into account during further processing of the error signal.

[0018] It is conceivable that, depending on the error information, the error signal voltage lies within an error operating voltage band specifically defined for the respective error or for a conceivable group of errors. Thus, as already described above, multiple error operating voltage bands can be provided, each of which can be assigned to at least one of the multiple error information. Therefore, at least one processing circuit can be adapted to generate a corresponding error signal when a specific error information occurs so that the error signal voltage of the error signal lies within one of the multiple error operating voltage bands, i.e., within the error operating voltage band assigned to the corresponding error information. It is also conceivable that multiple error signal voltages lie within a single error operating voltage band. In this case, the current voltage of each output signal can first be roughly classified as being within the error operating voltage band or the normal operating voltage band. Subsequently, a more refined determination of the current voltage of the output signal can be performed, specifically, to which error information the current voltage can be assigned if an error signal is present, or to which position state or rotational position the current voltage can be assigned if a sensor signal is present.

[0019] The present invention also relates to a control device for controlling the operation of a vehicle component including a rotatably and / or longitudinally displaceably supported component. The control device comprises a sensor device according to the above description and a control device, the control device being connected to the sensor device such that a signal generated by the sensor device is output to the control device. According to the present invention, the control device is adapted to check whether the corresponding generated signal is a sensor signal or an error signal based on the corresponding signal voltage. Furthermore, if the corresponding generated signal is a sensor signal, the control device is adapted to generate a control signal for controlling the operation of the vehicle component based on the position state of the component based on the sensor signal. Furthermore, if the corresponding generated signal is an error signal, the control device is adapted to generate a control signal for controlling the operation of the vehicle component based on the error signal, taking into account the presence of an error state, and / or generating a control signal for eliminating the error state based on the error signal. All advantages, features, and aspects described in conjunction with the sensor device according to the present invention are equally transferable to the control device according to the present invention, and vice versa.

[0020] It is conceivable that the control device is adapted to control the operation of an electric motor, which has a rotatably supported component designed as a rotor. The control device can also be adapted to control the operation of a transmission, which has a rotatably supported component designed as a transmission shaft or a transmission gear. It is furthermore conceivable that the control device is adapted to control the operation of a vehicle component having a component designed in particular as elongate and supported in a manner movable axially along a longitudinal direction. In this case, the vehicle component can be a transmission or a clutch device.

[0021] In the event of a sensor signal, the control of the vehicle component prescribed for normal operation is carried out by the control device. Otherwise, i.e. if the output signal is an error signal, the control of the vehicle component prescribed in particular for an error operation, precisely under the condition that an error state is present, is carried out by the control device. If a plurality of signal outputs for transmitting a plurality of output signals to the control device are provided in the sensor device, it can be prescribed that the output signal at the signal output at which the error state is currently present is not taken into account for determining the position state, in particular the rotational position, wherein only the remaining output signals or sensor signals are used for this purpose. In addition or alternatively, the control signal generated at the control device can cause the error state to be eliminated directly, for example on the condition that the error state arises only on the basis of a software-technically relevant situation and can be eliminated directly by the control signal.

[0022] As already described above in connection with the sensor device according to the application, if the at least one processing circuit is adapted to output the at least one error signal such that the error signal voltage of the at least one error signal is related to at least one error information, it is preferably prescribed that the control device is adapted to generate a control signal for controlling the operation of the vehicle component and / or to generate a control signal aimed at eliminating the error state of the respective type, depending on the error signal voltage and under the condition that the type of error state is taken into account. At this point, the error information determined at the sensor device is used at the control device to take measures specifically against the current respective error in the process of generating the control signal.

[0023] According to the present invention, it is contemplated that the control device has at least one signal input, via which a signal from the sensor device can be fed to an input circuit of the control device. The signal from the sensor device, or a signal generated therefrom, can be fed to at least one analog-digital converter connected to the input circuit, which can convert the signal into a digital signal for further processing in the control device and / or in a controller for the electric motor. Therefore, at least one electrical transmission element is provided between at least one signal output of the sensor device and at least one signal input of the control device, via which the output signal can be transmitted. The transmission element can be a conductor track of a printed circuit board or a current cable.

[0024] The output signal or a parameter or signal associated therewith is converted into a digital value using an analog-to-digital converter. Specifically, the signal voltage present at the analog-to-digital converter is converted into a digital value describing it. The digital values ​​can be stored in a continuously accumulated data structure, in which different signal voltage values ​​can be assigned to different moments in time. Based on the resulting data sequence, parameters of the sine or cosine shape of the sensor signal can be evaluated. Further processing of the digital signal is conceivable in a control unit of the control device and / or a controller of a vehicle component.

[0025] As already mentioned above, the output of an error signal has the advantage compared to the case in which the at least one signal output of the sensor device is switched to a high-impedance state in the event of an error. It is nevertheless also conceivable that the generation of an error signal is disadvantageous or not possible, for example when the sensor device is mechanically destroyed or the connection between the sensor device and the control device is broken. It is conceivable in this case within the scope of the application that the at least one signal output is switched or transferred to a high-impedance state when such a fault occurs and that this state is detected at the control device. It is also conceivable in this case that this is done if an error state or fault occurs in which no error information or no error information that can be determined is present. In this case, too, the signal output can be actively switched to a high-impedance state. It can therefore be provided in accordance with the application that the control device is adapted and / or designed to place the at least one signal output in a high-impedance state when a fault related to the control device occurs. It is conceivable in this case that the input circuit is adapted or designed to generate an electrical fault signal with a fault signal voltage by means of the input circuit and to deliver it to the analog-digital converter. It is conceivable in this case that the fault signal voltage differs from the voltage that occurs at the analog-digital converter when the at least one sensor signal is generated by the sensor device. It is also conceivable that the fault signal voltage differs from the voltage that occurs at the analog-digital converter when the at least one error signal is generated by the sensor device. It is therefore possible to specify a criterion that distinguishes whether a sensor signal or an error signal or a fault signal is present depending on the current voltage value.

[0026] It is also conceivable that the fault signal voltage lies within the range of the voltage that occurs at the analog-digital converter when the at least one sensor signal or the at least one error signal is generated by the sensor device. In this case, it is possible to specify a differentiation criterion, for example, in relation to the temporal behavior or change process of the respective signal. If the signal changes in a sinusoidal or cosine manner and is assigned to the normal operating voltage band, the signal is then considered to be a sensor signal at this time. If the signal remains almost constant and is assigned to the normal operating voltage band, the signal is then considered to be a fault signal at this time.

[0027] Within the scope of this embodiment, it is preferred to implement an improvement of the application in such a way that not only the distinguishability of the sensor signal from the error signal is specified, but also a signal that is likewise distinguishable from the sensor signal and the error signal, namely a fault signal, is caused to occur at the analog-digital converter in the case in which the signal output is placed in a high-impedance state by the input circuit.

[0028] Within the scope of this embodiment, the control device is preferably adapted to generate a control signal for controlling the operation of the vehicle component and / or to generate a control signal that is intended to eliminate the fault if a fault signal is applied at the analog-digital converter, taking into account the presence of the fault.

[0029] A specific embodiment of the control device or input circuit is conceivable in which the signal input or one of the signal inputs is connected to the analog-to-digital converter or one of the analog-to-digital converters via an input line of the input circuit having an input resistor, wherein the control device further comprises a voltage component that conducts an at least substantially constant supply voltage and / or a ground component that is connected to ground, or is connected to such a voltage component and / or ground component, wherein at least one branch leading to the voltage component or ground component and having a branch resistor is provided from the input line, in particular between the respective signal input and the input resistor. The supply voltage provided by means of the voltage component can be in the range of a maximum of 10 V. Preferably, the supply voltage is 5.0 V. The value of the input resistor and / or at least one branch resistor is, for example, several kiloohms.

[0030] It is conceivable to provide only a branch leading to the voltage component, but no branch leading to the ground component. The branch resistor provided can have a value such that, when a high-impedance state is present at the signal output, the signal, or more specifically the error signal voltage, present at the analog-to-digital converter is within the range present at the analog-to-digital converter when an error signal is generated by the sensor arrangement. The branch resistor can have a resistance value such that, in this case, the error voltage can be assigned to the upper error operating voltage range, wherein in this case, the branch resistor can also be referred to as a pull-up resistor.

[0031] It is also conceivable to provide only a branch leading to the ground component, but no branch leading to the voltage component. The branch resistor provided can have a value such that, when a high-impedance state is present at the signal output, the signal, or more specifically the error signal voltage, present at the analog-to-digital converter is within the range present at the analog-to-digital converter when an error signal is generated by the sensor device. The branch resistor can have a resistance value such that, in this case, the error voltage can be assigned to the lower error operating voltage range and / or to 0 V, wherein in this case the branch resistor can also be referred to as a pull-down resistor.

[0032] Finally, it is conceivable to provide not only a branch leading to the ground component but also a branch leading to the voltage component, wherein in this case, in particular when the two branch resistors have similar resistance values, the resulting circuit acts as a voltage divider, so that the fault signal voltage generated in this case can be distributed to the normal operating voltage band.

[0033] One conceivable problem is the occurrence of creepage currents / leakage currents, which can be caused, for example, by dirt or moisture and can bridge circuit components. If this condition involves a branch resistor or at least one of the branch resistors, and a shunt resistor is therefore present across the respective branch resistor, this can lead to changes in the signal present at the analog-to-digital converter, so that errors can occur in the information determined from the corresponding voltage present, such as the identification of a normal operating state, an error state, and / or a fault. To avoid this, it is conceivable that the error signal voltage differs sufficiently significantly from the voltage present at the analog-to-digital converter when the at least one sensor signal or the at least one error signal is generated by the sensor device, so that this difference remains despite the presence of at least one shunt resistor across the at least one branch resistor.

[0034] Therefore, when designing an input circuit or, more generally, a control device, it can be provided that a typical value exists for at least one shunt resistor, which is not caused by a specific electrical component but by contamination or moisture, wherein the values ​​of the remaining resistances, voltages, etc. are selected such that, even when a shunt resistor with a typical value exists, sufficient differentiation is possible between a fault and a normal operating state or other states. Typical values ​​of possible shunt resistors are known empirically and can, for example, be in the kiloohm range or higher.

[0035] The present invention also relates to a vehicle component for a motor vehicle, comprising a rotatably and / or longitudinally displaceably mounted component and at least one sensor device according to the above description. The present invention also relates to a vehicle component for a motor vehicle, comprising a rotatably and / or longitudinally displaceably mounted component and at least one control device according to the above description. All advantages, features, and aspects explained in conjunction with the sensor device according to the invention and / or the control device according to the invention are also transferable to the vehicle component according to the invention, and vice versa.

[0036] The vehicle component may be an electric motor having a rotatably mounted component designed as a rotor. The electric motor preferably includes a housing, wherein the stator of the electric motor is fixedly mounted relative to the housing, and the rotor is rotatably mounted relative to the housing. Control signals generated by a control device may be used during operation of the electric motor. Therefore, during control of the electric motor, it is generally necessary to know the current rotor position of the rotor for the current current setting of the motor windings.

[0037] The vehicle component may be a transmission having a rotatably and / or longitudinally displaceably supported component designed as a drive shaft or gear. During the control of the operation of an actuator (which forms part of the transmission or is operatively connected to a component of the transmission), during the speed change processes that can be achieved with the transmission, it is often necessary to know the position of the rotating body of the corresponding component. This also applies to the longitudinal position of the component.

[0038] The vehicle component may be a clutch device having a rotatably and / or longitudinally displaceably mounted component designed as a clutch plate or a clutch shaft. Thus, for example, information about whether a rotation is occurring in the component and / or the longitudinal position of the component can provide information about whether the clutch is currently engaged or disengaged.

[0039] The present invention further relates to a motor vehicle comprising a vehicle component having a rotatably and / or longitudinally displaceably mounted component and at least one sensor device or at least one control device according to the above description. All advantages, features, and aspects described in conjunction with the sensor device and / or the control device and / or the vehicle component according to the invention are also transferable to the motor vehicle according to the invention, and vice versa.

[0040] Finally, the present invention relates to a method for operating a sensor device for determining a positional state of a rotatably and / or longitudinally displaceably mounted component of a vehicle part of a motor vehicle, wherein the sensor device includes at least one processing circuit, which generates at least one electrical sensor signal having a sensor signal voltage that is dependent on the positional state and outputs it via at least one signal output. In this method, the object of the present invention is achieved according to the present invention by checking, with the at least one processing circuit, whether an error state associated with the sensor device exists, in which the generation of at least one sensor signal is interrupted, and, if the error state exists, generating, with the at least one processing circuit, at least one error signal having an error signal voltage that differs from the at least one sensor signal voltage and outputting it via at least one signal output. All advantages, features, and aspects described in conjunction with the sensor device according to the present invention, the control device according to the present invention, the vehicle part according to the present invention, and / or the motor vehicle according to the present invention are equally transferable to the method according to the present invention, and vice versa. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Further advantages and details of the invention will emerge from the exemplary embodiments described below and with reference to the drawings.

[0042] Schematically:

[0043] Figure 1 A block diagram of a motor vehicle according to the invention according to one embodiment is shown, comprising a vehicle component according to the invention according to one embodiment and designed as an electric machine, and a control device according to one embodiment, having a sensor arrangement according to the invention according to one embodiment.

[0044] Figure 2 Shown is the layout Figure 1 A front view of the sensor wheel or impeller at the rotor of the motor,

[0045] Figure 3 Shown with Figure 1 Wiring diagrams of the motor vehicle's control equipment, and

[0046] Figure 4 Shown with the help of Figure 1 A coordinate system for the temporal profiles and voltage levels of sensor signals and error signals generated by a sensor device of a motor vehicle. DETAILED DESCRIPTION

[0047] Figure 1 A schematic block diagram of a motor vehicle 1 according to the invention, in this case an electric vehicle, is shown according to one embodiment. Motor vehicle 1 includes a vehicle component 2 according to the invention, in one embodiment, which is an electric motor that implements a traction motor and by means of which electrical energy stored in an electrical energy storage device 3 of motor vehicle 1 can be converted into kinetic energy of motor vehicle 1 and vice versa. In principle, it is conceivable that the aspects explained below also apply to any vehicle component 2 having a component 5 that is mounted so as to be rotatable relative to a fixed portion of vehicle component 2, as is the case, for example, in a transmission.

[0048] Specifically and by way of example, in this example, it is provided that vehicle component 2 is an electric motor having a stator 4 and a rotatably mounted component 5 designed as a rotor, wherein stator 4 is fixed in rotation relative to a housing 6 of the electric motor or vehicle component 2, and rotor or component 5 is mounted so as to be rotationally movable together with a shaft 7 of component 5. To convert electrical energy into kinetic energy and vice versa, magnetic fields generated or present in the windings and any permanent magnets of stator 4 and rotor or component 5 interact with currents.

[0049] For this purpose, the electric machine or vehicle component 2 comprises power electronics 8, by means of which the DC voltage present at the electrical energy storage device 3 can be converted into an AC voltage present at the electric machine or vehicle component 2, and vice versa. The control required for this purpose is sometimes carried out according to control signals 10 generated by the control device 9 according to the invention (see Figure 3), control signals are transmitted from the control device 9 to the power electronics 8. The current position state or, more precisely, the rotational position of the rotor or component 5 provides the necessary control basis for this, since the windings present on the electric machine or vehicle component 2 are energized depending on the current rotational position.

[0050] In order to determine the current position state or rotational position of the rotor or component 5 (from which other parameters such as its rotational speed etc. can sometimes be determined), the control device 9 comprises, in addition to the control device 11, a sensor device 12 according to the invention according to one embodiment. Figure 3 Explain the working principle of the control device 9 according to the present invention, Figure 3 A circuit diagram of the control unit 9 is shown. The following description further explains the method according to the invention, which is carried out in the motor vehicle 1 or the control unit 9 , based on an exemplary embodiment.

[0051] Sensor arrangement 12 includes at least one sensor unit 13, each of which implements an eddy current distance sensor. Sensor unit 13 is arranged on the end face of shaft 7 in a fixed position relative to housing 6. A sensor wheel or impeller 37 made of metal is arranged on the end face of shaft 7. The sensor wheel or impeller can also be understood as a component of sensor unit 13 and rotates with it during the rotation of rotor or component 5.

[0052] In order to better understand the working principle of the sensor unit 13, Figure 2 FIG. 1 shows a front view of a sensor wheel or impeller 37, wherein the rotation axis 38 about which the rotor or member 5 rotates is perpendicular to the Figure 2 The sensor wheel or impeller 37 has raised sections or blades 39 which Figure 2is indicated by shading. Therefore, when component 5 rotates, blades 39 also rotate. Sensor unit 13 includes a transmitter and a receiver, illustratively etched onto circuit board 16 of processing circuit 15. The transmitter generates an alternating electromagnetic field, which is received by the receiver. This alternating field generates eddy currents in sensor wheel or impeller 37, which in turn dampen the alternating field. This effect, which is related to the distance between the transmitter or receiver and sensor wheel or impeller 37, can be determined by the strength of the alternating field received by the receiver. Furthermore, the strength of this effect varies with the rotation of component 5 and, therefore, sensor wheel or impeller 37, because eddy currents primarily occur in the area of ​​blades 39. The damping effect is strongest when one of blades 39 is centered or centrally located in the system comprising the transmitter and receiver. The damping effect is weakest when the gap between blades 39 in the system comprising the transmitter and receiver is centered or centrally located. The intensity of the alternating field received by the receiver varies periodically, in particular sinusoidally, between these two extreme states, wherein the values ​​received by the receiver are processed as measurement signals 14 by means of processing circuit 15. Viewed over time, the measurement signal has the shape of a superposition of two sinusoidal functions or pulsations, wherein the short period of this shape corresponds to the period of the alternating field, wherein the long period of this shape (which also forms a corresponding envelope curve) is generated by the rotation of the sensor wheel or impeller 37.

[0053] The processing circuit 15 is adapted and designed to generate a sensor signal 17 that correlates with the measurement signal 14 generated by the sensor unit 13 and thus describes the current rotational position of the rotor or component 5, respectively. The sensor signal 17 is output to the control device 11 via a signal output 18 of the sensor device 12. The sensor signal 17, which is output as a voltage value, is related to the intensity of the alternating field received by the receiver and is therefore present in the form of a corresponding sinusoidal oscillation with the periodic envelope already described.

[0054] Sensor signal 17 is output four times in total, specifically via four different signal outputs 18 of sensor device 12, each of which is connected to processing circuit 15. The information about the positional state or rotational position of component 5 output via these four signal outputs 18 is redundant, but required for safety reasons, for example, according to a predetermined ASIL classification (ASIL stands for "Automotive Safety Integrity Level"). At the first signal output 18, sensor signal 17 is output as a sinusoidal signal. At the second signal output 18, sensor signal 17 is output as a corresponding negative sinusoidal signal, thereby forming the second envelope curve of all existing envelope curves. At the third signal output 18, sensor signal 17 is output as a cosine signal. At the fourth signal output 18, sensor signal 17 is output as a corresponding negative cosine signal. Processing circuit 15 is therefore adapted to generate these four signal outputs as redundant information carriers based on measurement signal 14.

[0055] The components just explained, namely the sensor unit 13 with the transmitter and receiver, the processing circuit 15 associated with the sensor unit 13, and the four signal outputs 18, are all present in duplicate, as an example. Accordingly, for safety reasons, the detection of the measurement signal 14 and the generation of the sensor signal 17 therefrom are also performed in duplicate. Thus, in the sensor device 12, there are a total of eight signal outputs 18, each of which supplies a measurement signal 14 independently of one another. For the sake of clarity, Figure 3 Only one of the eight signal outputs 18 and one of the two processing circuits 15 is shown in FIG. The same applies to the components associated with the signal outputs 18 on the part of the control device 11, which are also provided in eight parts.

[0056] The processing circuits 15 are each designed as a so-called application-specific integrated circuit, or "ASIC" for short. Alternatively, the processing circuits 15 can each be designed as a so-called application-specific standard product, or "ASSP" for short. Like the sensor unit 13, the processing circuits 15 are carried by or arranged on a circuit board 16, which in turn is located on the shaft 7 at the end.

[0057] Although for the sake of simplicity only one sensor signal 17 or one of the eight signal outputs is referred to below, a corresponding sensor signal 17 is output for each of the signal outputs 18 by means of the sensor device 12. Therefore, in the following, reference is made in particular to Figure 4 Explain the specific details of the sensor signal 17. Figure 4A coordinate system is shown, the abscissa of which represents time and the ordinate represents the voltage value present at the signal output 18, i.e. the sensor signal 17. In the example shown, the rotor or component 5 rotates uniformly or evenly, i.e. at a constant angular velocity. In this case, the processing circuit 15 generates the sensor signal 17 in such a way that the corresponding sensor signal voltage varies periodically, i.e. in this example sinusoidally. The period of this periodic variation corresponds to the duration of one complete rotation of the rotor. The sensor signal voltage is understood to be the voltage value present at the signal output 18 during the generation of the sensor signal 17. In this case, the sensor signal voltage is always at Figure 4 The normal operating voltage band 19 (which may also be referred to as a normal operating voltage interval) is marked by hatching in FIG. In this example, the normal operating voltage band exemplarily includes a range between a lower voltage value of 0.5V and an upper voltage value of 4.0V.

[0058] The sensor device 12 and the control device 11 are connected to each other in such a way that the sensor signal 17 output through the signal output terminal 18 reaches the analog-to-digital converter 22 of the control device 11 via the signal input terminal 20 and the input circuit 21 of the control device 11. The analog-to-digital converter converts the voltage value appearing at the analog-to-digital converter 22 into a digital signal and outputs it to the control unit 23 of the control device 11. The control unit generates the control signal 10 based on the sensor signal 17 converted into a digital signal and outputs it to the power electronic device 8 or a controller assigned to the power electronic device 8 and not shown in detail in the figure.

[0059] The aspects explained so far regarding the generation of control signal 10 relate to the normal operating state of sensor device 12 or control device 9, in which the generation of sensor signal 17 based on measurement signal 14 can be carried out normally and therefore without restriction. The following explains the situation in which an error state occurs, in which the generation of sensor signal 17 is interrupted or cannot be carried out normally and without error. Processing circuit 15 is adapted and designed to check whether such an error state, i.e., a sensor-internal error, exists. In this case, an error signal 24 is output to control device 11 via signal output 18 by means of processing circuit 15 instead of sensor signal 17. The generated error signal 24 differs from sensor signal 17 in that the error signal voltage of error signal 24 differs from or is different from the sensor signal voltage. The error signal voltage is to be understood as the voltage value present at signal output 18 during the generation of error signal 24.

[0060] In this regard, the processing circuit 15 is adapted to generate the error signal 24 such that the error signal voltage is within the error operating voltage band 25. Specifically and exemplarily, in this example, the error signal 24 is generated. Figure 4 , two faulty operating voltage bands 25 are indicated by hatching. It is provided that the faulty operating voltage bands 25 deviate from the normal operating voltage band 19 in a non-intersecting manner, i.e., no voltage value can be assigned to both voltage bands 19, 25 simultaneously. Preferably, there is a gap between each of the voltage bands 19, 25. In this exemplary embodiment, it is provided that the upper faulty operating voltage band 25 is located above and spaced apart from the normal operating voltage band 19, and the lower faulty operating voltage band 25 is located below and spaced apart from the normal operating voltage band 19.

[0061] Another aspect related to error states is the situation in which processing circuit 15 determines error information related to the type or nature of the currently existing error state. Based on this error information, a corresponding error signal 24 is generated and output such that the error signal voltage of the correspondingly generated error signal 24 is related to the error information and, therefore, the type or nature of the current error state. For example, processing circuit 15 is adapted to identify a short circuit as an error state and assign it to the error information associated therewith. In this case, the error signal voltage is adjusted to a value specifically predetermined for this error information, such as a value within the upper or lower error operating voltage band of the two error operating voltage bands 25. Thus, error signals 24 with different error signal voltages are output for different error states. Regarding short circuits, various scenarios can be anticipated or differentiated in the generation or detection of error information, namely, a short circuit between one of the eight lines connecting one of the signal outputs to one of the signal inputs 20 and a line carrying the supply voltage, a short circuit between a line carrying the ground voltage, or a short circuit between one of the eight lines connecting one of the signal outputs to one of the signal inputs 20. Furthermore, it is conceivable for the error message to be detected during a fault diagnosis or self-diagnosis within processing circuit 15 , for example, when a sensor detects that a temperature limit value has been exceeded in one of the components of processing circuit 15 .

[0062] Analogously to the sensor signal 17, the error signal 24 is subsequently supplied to an analog-to-digital converter 22, which likewise converts the error signal 24 into a digital signal and supplies it to a control unit 23. The control device 11 or the control unit 23 is adapted to check, based on the current signal voltage, whether the respectively present signal 17, 24 is a sensor signal 17 or an error signal 24.

[0063] In the first case, when sensor signal 17 is present and therefore a normal operating state exists, a control signal 10 for controlling the operation of the electric machine or vehicle component 2 is generated and output according to the above explanation. In the second case, when error signal 24 is present and therefore an error state exists, control device 11 also generates and outputs a control signal 10 for controlling the operation of the electric machine or vehicle component 2, but hereby takes into account the presence of error signal 24 at the corresponding signal output 18. In this case, only the signals or sensor signals 17 outputted via the other signal outputs 18 that are not affected by the error state are used to determine the rotational position of the rotor or component 5. Furthermore, in this case, a control signal 10 is generated to eliminate the error state. Specifically, this control signal 10 causes, for example, an output via an output device (not shown in greater detail) of motor vehicle 1, which informs the driver of the error state and, if necessary, requests the driver to visit a repair shop.

[0064] Furthermore, the control device 11 or the control unit 23 is adapted to generate a control signal 10 specifically for the respective current error state based on the current error signal voltage (which in turn is correlated with the error information). Thus, the user output can also simultaneously include information about the type or nature of the error state, for example. If possible, the control signal 10 generated by the control unit 23 prompts the direct elimination of the error state, for example, if the error state occurs only due to software-related circumstances and can be eliminated directly via the control signal 10.

[0065] The following describes a situation in which a fault exists on the part of control device 9. A fault differs from the previously mentioned error states in that, in the case of a fault, no error information is present and, therefore, no dedicated error signal voltage can be predefined in this regard on the part of sensor device 12. An example of this is, for example, that at least one of the components of sensor device 12 is damaged or mechanically destroyed.

[0066] Control device 9 is adapted or designed to place signal output 18 in a high-impedance state in this situation. This means that the ohmic resistance present at signal output 18 is so high that this situation corresponds only to an interruption in the line connecting signal output 18 to signal input 20. In this situation, a fault signal is generated at analog-to-digital converter 22 that is related only to the situation at control device 11 and not to the situation at sensor device 12. It is conceivable that input circuit 21 causes the fault signal or the fault signal voltage value to differ from all conceivable voltage values ​​present at analog-to-digital converter 22 in other situations, i.e., when sensor signal 17 or error signal 24 is present. Control device 11 or control unit 23 is adapted to generate control signal 10 when the fault signal is present, taking into account the presence of the fault, and output it to electric machine or vehicle component 2. Furthermore, control signal 10 is generated to eliminate the fault, for example, by causing a corresponding output via an output device.

[0067] Reference below Figure 3 The following are exemplary details of the input circuit 21. The signal input 20 is connected to an analog-to-digital converter 22. A high-impedance input resistor 26, i.e., in the kilo-ohm range, is connected to an input line 28 provided for this purpose. Furthermore, a voltage component 29 is provided, which is connected to a voltage source 27 and conducts the supply voltage. This voltage component is designed as a line. In this example, the supply voltage is, for example, 5.0 volts. Furthermore, a grounding component 30 is provided, which is also designed as a line. Between the signal input 20 and the input resistor 26, two branches 31 and 32 branch from the input line 28. The first branch 31 leads to the voltage component 29 via a first branch resistor 33 (also known as a pull-up resistor). The second branch 32 leads to the grounding component 30 via a second branch resistor 34 (also known as a pull-down resistor). Like the input resistor 26, the branch resistors 33 and 34 are high-impedance and therefore in the kilo-ohm range.

[0068] It is obvious that, when the signal output 18 is placed in a high impedance state, the fault signal voltage appearing at the analog-to-digital converter 22 depends only on the supply voltage and the values ​​of the resistors 26 , 33 , 34 . Figure 4 , which value lies, for example, in a range that cannot be assigned to either of the voltage bands 19, 25. Specifically, the fault voltage signal differs so significantly from the value that occurs at the analog-digital converter 22 when the sensor signal 17 or the error signal 24 is present that, even with the presence of at least one shunt resistor 35, 36, sufficient differentiation of the fault signal from the signals 17, 24 is achieved on the part of the control device 11 or the control unit 23.

[0069] Reference Figure 3 In the circuit shown in FIG, a first shunt resistor 35 connected across the first branch resistor 33 can be envisaged. In addition or alternatively, a second shunt resistor 36 connected across the second branch resistor 34 can be envisaged. Figure 3 Shunt resistors 35 and 36, shown in dashed lines (which are not actual electronic components but may be present due to contamination or moisture), result in a certain degree of parallel connection of one of shunt resistors 35 and 36 with the respective associated branch resistor 33 and 34. This obviously results in the fault signal voltage actually occurring at analog-to-digital converter 22 differing from the ideal case in which shunt resistors 35 and 36 are absent. However, in this example, the supply voltage and the values ​​of resistors 26, 33, and 34 are selected so that the deviation in the fault signal voltage resulting from the typical values ​​of shunt resistors 35 and 36 is sufficiently small to allow a distinction between normal operation, malfunction, and a fault.

[0070] In contrast to what has been explained above, it is also conceivable to have the fault signal voltage be in the range that occurs at the analog-digital converter 22 when the sensor signal 17 or the error signal 24 is generated by the sensor device 12. In this case, it is conceivable to distinguish between the two cases by the temporal behavior of the respective signal. If the signal changes sinusoidally or cosinusoidally and is assigned to the normal operating voltage band 19, then this signal is considered to be a sensor signal 17. If the signal remains almost constant and is assigned to the normal operating voltage band 19, then this signal is considered to be a fault signal. Thus, in Figure 3 The input circuit 21 shown in FIG. 2 , which comprises two branch resistors 33 , 34 with similar resistance values, serves as a voltage divider, so that the generated fault signal voltage can be distributed to the normal operating voltage band.

[0071] refer to Figure 3 It is also conceivable that the distinction between the presence of an error signal 24 and a fault signal is not achieved. Thus, for example, according to the first case, it is conceivable to provide only the first branch 31 and the first branch resistor 33, without providing the second branch 32 and the second branch resistor 34. The first branch resistor 33 has a value such that, when a high-impedance state is present at the signal output 18, the signal or fault signal voltage present at the analog-to-digital converter 22 lies within a range that can be assigned to the upper fault operating voltage band 25, wherein in this case the branch resistors can also be referred to as pull-up resistors.

[0072] According to a second case, it is conceivable to provide only the second branch 32 and the second branch resistor 34, without providing the first branch 31 and the first branch resistor 33. The second branch resistor 34 has a value such that, when a high-impedance state is present at the signal output 18, the signal or fault signal voltage present at the analog-digital converter 22 is within a range assignable to the lower fault operating voltage band 25 or is 0 V, wherein in this case the branch resistor can also be referred to as a pull-down resistor.

[0073] In addition, it should be noted that motor vehicle 1 includes additional vehicle components 2 according to the present invention, which operate in a similar manner with respect to the transmission of the signals 17 and 24 described above and are therefore not shown separately in the figures for the sake of clarity. Unlike vehicle components 2 configured as electric motors, these additional vehicle components 2 provide for a longitudinally displaceable component 5 instead of a rotatably mounted component 5, or for a rotatably mounted component 5 to be supported longitudinally. This applies, for example, to the transmission already described above. Furthermore, a clutch device is provided as one of the additional vehicle components 2. In both the transmission and the clutch devices, the longitudinally displaceable component 5 is a longitudinally displaceable shaft, on which a further sensor device 12 according to the present invention is respectively disposed. In both the transmission and the clutch devices, the current longitudinal position, or in other words, the axial displacement, is determined as a positional state, either in addition to or in addition to the current rotational position of the component 5.

Claims

1. A sensor device (12) for determining a position state of a rotatably and / or longitudinally displaceably supported component (5) of a vehicle part (2) of a motor vehicle (1), the sensor device comprising at least one processing circuit (15) adapted to generate at least one electrical sensor signal (17) having a sensor signal voltage which is dependent on the position state and to output the sensor signal via at least one signal output (18), characterized in that The at least one processing circuit (15) is further adapted to check whether an error state is present in relation to the sensor device (12) in which the generation of the at least one sensor signal (17) is interrupted, to generate at least one error signal (24) having an error signal voltage that differs from the at least one sensor signal voltage if the error state is present, and to output the error signal via the at least one signal output terminal (18).

2. The sensor device (12) according to claim 1, characterized in that At least one sensor unit (13) is capable of generating at least one measurement signal (14) related to the position state and of outputting the measurement signal to the at least one processing circuit (15), wherein the at least one processing circuit (15) is adapted to generate the at least one sensor signal (17) as a function of the at least one measurement signal (14).

3. The sensor device (12) according to claim 2, characterized in that The at least one sensor unit (13) constitutes an eddy current distance sensor.

4. The sensor device (12) according to any one of the preceding claims, characterized in that The at least one processing circuit (15) is adapted to generate the at least one sensor signal (17) in such a way that a sensor signal voltage of the at least one sensor signal (17) varies periodically, in particular sinusoidally, within a normal operating voltage band (19) when the rotatably supported component (5) rotates at a constant speed.

5. The sensor device (12) according to claim 4, characterized in that The at least one processing circuit (15) is adapted to generate at least one error signal (24) such that an error signal voltage of the at least one error signal (24) is within at least one error operating voltage band (25), wherein the at least one error operating voltage band (25) is located above or below a normal operating voltage band (19).

6. The sensor device (12) according to any one of the preceding claims, characterized in that The at least one processing circuit (15) is adapted to determine at least one error information related to the type or characteristics of an error state and to output the at least one error signal (24) such that an error signal voltage of the at least one error signal (24) is correlated with the at least one error information.

7. A control device (9) for controlling the operation of a vehicle component (2) comprising a rotatably and / or longitudinally displaceably mounted component (5), the control device comprising a sensor device (12) according to any one of the preceding claims and a control device (11), the control device being connected to the sensor device in such a way that a signal (17, 24) generated by means of the sensor device (12) is output to the control device (11), wherein: The control device (11) is adapted to check, based on the corresponding signal voltage, whether the corresponding generated signal (17, 24) is a sensor signal (17) or an error signal (24), wherein the control device (11) is further adapted to - if the respectively generated signal (17, 24) is a sensor signal (17), generating a control signal (10) for controlling the operation of the vehicle component (2) as a function of the position state of the component (5) as a function of the sensor signal, - if the respectively generated signal (17, 24) is an error signal (24), generating a control signal (10) for controlling the operation of the vehicle component (2) taking into account the presence of an error state and / or generating a control signal (10) intended to eliminate the error state based on the error signal.

8. The control device (9) according to claim 7, wherein The at least one processing circuit (15) is adapted to output the at least one error signal (24) in such a way that an error signal voltage of the at least one error signal (24) is correlated with the at least one error information, characterized in that the control device (11) is adapted to generate a control signal (10) for controlling the operation of the vehicle component (2) and / or to generate a control signal (10) intended to eliminate an error state of the corresponding type as a function of the error signal voltage and taking into account the type of the error state.

9. The control device (9) according to claim 7 or 8, characterized in that The control device (11) has at least one signal input (20), via which a signal (17, 24) of a sensor device (12) can be supplied to an input circuit (21) of the control device (11), wherein the signal (17, 24) of the sensor device (12) or a signal generated therefrom can be supplied to at least one analog-digital converter (22) connected to the input circuit (21), by means of which the signal can be converted into a digital signal for further processing.

10. The control device (9) according to claim 9, characterized in that The control device (9) is adapted and / or designed to place the at least one signal output (18) in a high-impedance state when a fault associated with the control device (9) occurs, wherein in this case an electrical fault signal having a fault signal voltage is generated by means of an input circuit (21) and the electrical fault signal is supplied to an analog-to-digital converter (22), wherein the control device (11) is adapted to generate a control signal (10) for controlling the operation of the vehicle component (2) taking into account the presence of the fault and / or to generate a control signal (10) intended to eliminate the fault if the fault signal is applied to the analog-to-digital converter (22).

11. The control device (9) according to claim 9 or 10, characterized in that The signal input (20) or one of the signal inputs (20) is connected to the analog-to-digital converter (22) or one of the analog-to-digital converters (22) via an input line (28) of an input circuit (21) having an input resistor (26), wherein the control device (11) also has or is connected to a voltage component (27) that conducts an at least substantially constant supply voltage and / or a ground component (30) that is connected to ground, wherein at least one branch (31, 32) leading to the voltage component (27) or the ground component (30) and having a branch resistor (33, 34) is provided starting from the input line (28), in particular between the respective signal input (20) and the input resistor (26).

12. A vehicle component (2) for a motor vehicle (1), comprising a component (5) which is supported so as to be rotatable and / or longitudinally displaceable and at least one sensor device (12) according to any one of claims 1 to 6 or at least one control device (9) according to any one of claims 7 to 11.

13. The vehicle component according to claim 12, characterized in that The vehicle components are: an electric machine having a rotatably mounted component (5) designed as a rotor, or a transmission having a rotatably and / or longitudinally displaceably mounted component (5) designed as a transmission shaft or a transmission gear, or A clutch device having a rotatably and / or longitudinally displaceably mounted component (5) designed as a clutch disk or a clutch shaft.

14. A motor vehicle (1) comprising a vehicle component (2) having a component (5) which is supported so as to be rotatable and / or longitudinally displaceable and at least one sensor device (12) according to any one of claims 1 to 6 or at least one control device (9) according to any one of claims 7 to 11.

15. A method for operating a sensor device (12) for determining a position state of a rotatably and / or longitudinally displaceably mounted component (5) of a vehicle part (2) for a motor vehicle (1), wherein: The sensor device (12) comprises at least one processing circuit (15), with the aid of which at least one electrical sensor signal (17) having a sensor signal voltage is generated and output via at least one signal output terminal (18), characterised in that with the aid of the at least one processing circuit (15) a check is performed to determine whether an error state associated with the sensor device (12) exists, in which the generation of the at least one sensor signal (17) is interrupted, and in the event of an error state at least one error signal (24) having an error signal voltage that differs from the at least one sensor signal voltage is generated with the aid of the at least one processing circuit (15), and the error signal is output via the at least one signal output terminal (18).

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