Position Sensors

Abstract

The position sensor comprises: a detection unit, which generates a plurality of detection signals corresponding to a plurality of ranges arranged in one direction along the moving direction of the detection object and having different phase differences, based on changes in a magnetic field received from the detection object as the detection object composed of a magnetic body moves; and a signal processing unit, which obtains the plurality of detection signals from the detection unit, compares the plurality of detection signals with a threshold value, and determines the position of the detection object as a position in a certain range among the plurality of ranges based on a combination of the magnitude relationship between the plurality of detection signals and the threshold value, wherein the detection object has a reference portion and a moving portion different from the reference portion, and the signal processing unit outputs a position signal of a value corresponding to the range of the position of the detection object determined by the signal processing unit, among discrete values ​​set for the plurality of ranges, to an external device based on a transition from the moving portion of the detection object to the reference portion of the detection object.

Description

[0001] This application is a divisional application of the Chinese patent application with application date of 2018 / 05 / 17, application number 201880038375.3, and invention name “Position Sensor”.

[0002] Cross-reference to related applications

[0003] This application is based on Japanese Patent Application No. 2017-117170 filed on June 14, 2017, the contents of which are incorporated herein by reference. Technical Field

[0004] The present disclosure relates to a position sensor that outputs a signal corresponding to the position of a detection object. Background Art

[0005] In the past, for example, Patent Document 1 proposed a linear position sensor having a permanent magnet, a magnetic field sensor, and an evaluation circuit. In this sensor, the permanent magnet and the magnetic field sensor can move relative to each other along a moving path. In addition, the magnetic field sensor generates an output signal determined by the direction of the magnetic field. The evaluation circuit converts the output signal of the magnetic field sensor into a signal proportional to the measured path.

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Publication No. 2006-153879 Summary of the invention

[0009] However, in the above-mentioned related technologies, since the detection object is a magnet itself or is equipped with a magnet, additional processes for detecting the object and assembly of the magnet are required. Therefore, the number of processes, assembly man-hours, and number of parts increase, which becomes the cause of detection position error. In addition, detection position error may also occur due to signal offset at the interface and A / D conversion error included in the proportional signal.

[0010] An object of the present disclosure is to provide a position sensor capable of suppressing the occurrence of a detection position error.

[0011] A position sensor in one aspect of the present disclosure includes a detection unit that generates a plurality of detection signals having different phase differences and corresponding to a plurality of ranges arranged in one direction along a moving direction of the detection object based on changes in a magnetic field received from the detection object as the detection object formed of a magnetic body moves.

[0012] In addition, the position sensor has a signal processing unit, which obtains multiple detection signals from the detection unit, compares the multiple detection signals with a threshold, and determines the position of the detection object as a position in a certain range of multiple ranges based on a combination of the size relationship between the multiple detection signals and the threshold.

[0013] Thus, the detection unit detects the position under the influence of the magnetic field from the detection object, so the detection object does not necessarily need to have a magnet. Therefore, the number of processing, assembly man-hours, and the number of parts will not increase, and the detection position error caused by the magnet will not occur. In addition, since the signal processing unit detects the position of a certain range among multiple ranges of the detection object, the detection position error caused by signal offset and A / D conversion error contained in the signal will not occur. Therefore, the generation of the detection position error can be suppressed. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The above-mentioned purpose and other purposes, features and advantages of the present disclosure will become more apparent through reference to the accompanying drawings and the following detailed description. The accompanying drawings are:

[0015] Figure 1 is an appearance diagram of a position sensor according to a first embodiment of the present disclosure,

[0016] Figure 2 This is an exploded perspective view of the components constituting the magnetic detection method using the magnetoresistive element.

[0017] Figure 3 yes Figure 2 A top view of the components shown,

[0018] Figure 4 yes Figure 3 IV-IV cross-section diagram,

[0019] Figure 5 is a diagram for explaining a detection signal based on a magnetoresistive element.

[0020] Figure 6 is a top view showing the components constituting the magnetic detection method using the Hall element,

[0021] Figure 7 yes Figure 6 Section VII-VII of

[0022] Figure 8 This is a diagram for explaining the detection signal based on the Hall element.

[0023] Fig. 9 is a diagram showing a circuit configuration of a position sensor.

[0024] Fig.10is a diagram showing a detection signal, a state determination, and a position signal when three states are detected.

[0025] Fig.11 : is a diagram showing a case where four states are determined as a modified example.

[0026] Fig.12 FIG. 1 is a diagram showing a case where a detection signal is generated based on the outputs of two element pairs as a modified example.

[0027] Fig.13 1 is a diagram showing a case where a detection signal is generated based on outputs of three element pairs as a modified example.

[0028] Fig.14 FIG. 1 is a diagram showing a case where a detection signal is generated based on outputs of five element pairs as a modified example.

[0029] Fig.15 FIG. 1 is a diagram showing a case where, as a modified example, three detection signals are generated based on the outputs of four element pairs and five states are determined.

[0030] Fig.16 FIG. 1 is a diagram showing a case where, as a modified example, three detection signals are generated based on the outputs of three element pairs and six states are determined.

[0031] Fig.17 FIG. 1 is a diagram showing a case where, as a modified example, four detection signals are generated based on the outputs of four element pairs and seven states are determined.

[0032] Fig.18 FIG. 4 is a diagram showing a case where, as a modified example, four detection signals are generated based on the outputs of five element pairs and eight states are determined.

[0033] Fig.19 2 is a diagram showing a case where two thresholds are used to determine seven states as a modified example.

[0034] Fig. 20 FIG. 1 is a diagram showing a case where three states are determined based on outputs of three Hall elements as a modified example.

[0035] Fig.21 is a diagram showing a deformation example of the shaft,

[0036] Fig. 22 is a diagram showing an example of a detection object,

[0037] Fig.23 is a diagram showing an example of a detection object,

[0038] Fig.24 is a diagram showing the axis of the second embodiment,

[0039] Fig.25 Yes Fig.24 The diagrams of detection signals, state judgments, and position signals when the axis detects three states are shown.

[0040] Fig.26 : is a diagram showing a case where four states are determined as a modified example.

[0041] Fig. 27 is a diagram showing an example of a detection object,

[0042] Fig.28 is a diagram showing an example of a detection object,

[0043] Fig.29 This is a diagram showing discrete pulse widths when three states are determined in the third embodiment. DETAILED DESCRIPTION

[0044] Hereinafter, embodiments of the present disclosure will be described based on the drawings. In addition, in the following embodiments, the same or equivalent parts are denoted by the same reference numerals in the drawings.

[0045] (First Embodiment)

[0046] Hereinafter, a first embodiment of the present disclosure will be described with reference to the drawings. The position sensor of the present embodiment is a sensor that detects in which range (state) the position of a detection target is located and outputs a signal corresponding to the range.

[0047] like Figure 1 As shown, the position sensor 100 detects the position of the shaft 200 linked to the shift position of the vehicle. Specifically, the position sensor 100 detects a signal corresponding to the position of the protrusion 201 provided on the shaft 200 to obtain the state of the shaft 200.

[0048] The state of the shaft 200 refers to the position of the shaft 200 when the gear is operated by the user. For example, the shaft 200 moves in conjunction with the parking gear of the gear. Figure 1 As shown in FIG. 1 , when the shift position is operated to the parking position, the shaft 200 moves in the axial direction. Thus, the shaft 200 reflects the state of the parking position. The position sensor 100 detects a position on the shaft 200 that is closer to the front side than the protrusion 201 .

[0049] On the other hand, when the shift position is operated so as to be located at a position other than the parking position, the shaft 200 reflects the state other than the parking position. In this case, the position sensor 100 detects the protrusion 201 in the shaft 200 and the position further to the depth side than the protrusion 201. Of course, the shaft 200 may also move in conjunction with the position other than the parking position.

[0050] The shaft 200 is entirely formed of a magnetic material, for example. Alternatively, the surface of the protrusion 201 of the shaft 200 that faces the position sensor 100 may be formed of a magnetic material, and the other portions may be formed of other metal materials.

[0051] The position sensor 100 includes a housing 101 formed by resin molding of a resin material such as PPS. The housing 101 includes a front end 102 on the shaft 200 side, a flange 103 fixed to a peripheral mechanism, and a connector 104 for connecting a harness. A sensing portion is provided inside the front end 102.

[0052] The position sensor 100 is fixed to the peripheral mechanism via the flange portion 103 so that the front end portion 102 has a predetermined gap with respect to the protrusion 201 of the shaft 200 . Therefore, the shaft 200 moves relative to the position sensor 100 .

[0053] In addition, although not shown, the position sensor 100 may be fixed to the peripheral mechanism in a manner to detect the position of a valve that moves in conjunction with the shaft 200. In addition, the moving direction of the shaft 200 is not limited to straight movement or reciprocation, and may also be rotation, reciprocation within a specific angle, etc. In this way, the position sensor 100 can be applied to the detection of the position, movement, rotation, etc. of a movable part that moves in conjunction with the movement of the gear position of the vehicle.

[0054] The position sensor 100 can adopt a magnetic detection method using a magnetoresistive element or a magnetic detection method using a Hall element. In the case of a magnetic detection method using a magnetoresistive element, Figure 2 As shown, the position sensor 100 includes a molded IC portion 105, a magnet 106, and a holder 107. These are accommodated in the front end portion 102 of the housing 101. The molded IC portion 105 is inserted into the hollow cylindrical magnet 106. The magnet 106 is inserted into the bottomed cylindrical holder 107.

[0055] like Figure 3 The floor plan and Figure 4 As shown in the cross-sectional schematic diagram of , the molded IC part 105, the magnet 106, and the holding part 107 are integrated. The main part of the molded IC part 105 is located in the hollow part of the magnet 106. The holding part 107 fixes the positions of the molded IC part 105 and the magnet 106.

[0056] The molded IC unit 105 includes a lead frame 108, a processing circuit chip 109, a sensor chip 110, and a molded resin unit 111. The lead frame 108 includes a plate-shaped island 112 and a plurality of leads 113 to 115. The island 112 is arranged so that its plane portion is perpendicular to the moving direction of the detection object.

[0057] The plurality of leads 113 to 115 correspond to a power supply terminal 113 to which a power supply voltage is applied, a ground terminal 114 to which a ground voltage is applied, and an output terminal 115 for outputting a signal. That is, each lead 113 to 115 is for power supply, grounding, and signal. A terminal 116 is connected to the front end of each lead 113 to 115. The terminal 116 is located in the connector portion 104 of the housing 101. In addition, the terminal 116 is connected to the wiring harness.

[0058] In the present embodiment, the grounding lead 114 among the plurality of leads 113 to 115 is integrated with the island 112. The island 112 may be completely separated from all the leads 113 to 115.

[0059] The processing circuit chip 109 and the sensor chip 110 are mounted on the island 112 by adhesive or the like. The processing circuit chip 109 is configured with a circuit portion for processing the signal of the sensor chip 110. The sensor chip 110 includes a magnetoresistive element whose resistance value changes when it is affected by a magnetic field from the outside. The magnetoresistive element is, for example, AMR, GMR, or TMR. Each lead 113 to 115 is electrically connected to the processing circuit chip 109 via a wire 117. The processing circuit chip 109 and the sensor chip 110 are electrically connected via a wire 118.

[0060] The mold resin portion 111 seals the island portion 112, a part of each of the leads 113 to 115, the processing circuit chip 109, and the sensor chip 110. The mold resin portion 111 is molded into a shape fixed to the hollow portion of the magnet 106.

[0061] The detection signal based on the magnetic detection method using the magnetoresistive element is described. Figure 5 As shown in FIG. 1 , the holding portion 107 is arranged with a predetermined gap relative to the protrusion 201 to be detected. When the protrusion 201 moves relative to the holding portion 107, the detection signal becomes maximum at the center of the moving direction of the protrusion 201. If the gap becomes larger, the amplitude of the detection signal becomes smaller, and if the gap becomes smaller, the amplitude of the detection signal becomes larger. By setting a threshold value for such a detection signal, the position of the protrusion 201 can be detected.

[0062] In addition, Figure 5, only the relationship between the movement of the protrusion 201 and the detection signal by the magnetic detection element is shown. As will be described later, the detection signal is generated based on the output of a plurality of magnetoresistive elements.

[0063] When using a magnetic detection method using a Hall element, such as Figure 6 The floor plan and Figure 7 As shown in the cross-sectional schematic diagram of , the molded IC part 105 is inserted and fixed to the holding part 107. In addition, the molded IC part 105 includes a lead frame 108, an IC chip 119, a magnet 120, and a molded resin part 111.

[0064] The island 112 of the lead frame 108 is arranged so that the plane portion is parallel to the moving direction of the detection object. On the other hand, each lead 113 to 115 is arranged so as to be perpendicular to the moving direction of the detection object. The grounding lead 114 is integrated with the island 112 at a right angle. Terminals 116 are connected to the front ends of each lead 113 to 115.

[0065] A plurality of Hall elements and a signal processing circuit are formed on the IC chip 119. That is, in the magnetic detection method using the Hall element, a single chip structure is formed. The magnet 120 is fixed to the surface of the island 112 on the side opposite to the IC chip 119. Each lead 113 to 115 is electrically connected to the IC chip 119 via a wire 121. The molded resin portion 111 is formed into a shape fixed to the hollow portion of the holding portion 107.

[0066] The detection signal based on the magnetic detection method using the Hall element is described. Figure 8 As shown, for example, when two Hall elements (X, Y) are arranged above the magnet 120, when the protrusion 201 moves relative to the holding portion 107, each detection signal becomes maximum corresponding to the position of each Hall element (X, Y). The relationship between the gap and the amplitude of the detection signal is the same as that of the magnetic detection method using a magnetoresistive element. By setting a threshold value for each detection signal, the position of the protrusion 201 can be detected.

[0067] In this embodiment, the method using the magnetoresistive element in the above-mentioned magnetic detection method is adopted. The magnetoresistive element for detecting the magnetic vector has the advantage of being able to eliminate the accuracy error caused by the offset of the gap. In addition, it has the advantage of being able to reduce or eliminate the influence of the stress generated on the sensor chip 110. Thus, high-precision detection can be performed.

[0068] Next, the circuit structure formed in the sensor chip 110 and the processing circuit chip 109 is described. Fig. 9As shown, the position sensor 100 and the controller 300 are electrically connected via the harness 400. As described above, since the molded IC unit 105 has three leads 113 to 115, the harness 400 includes three wires.

[0069] The controller 300 is, for example, a transmission controller (TCU). The controller 300 includes a power supply unit 301, a control unit 302, and a grounding unit 303. The power supply unit 301 is a circuit unit that supplies a power supply voltage to the position sensor 100. The control unit 302 is a circuit unit that performs a predetermined control based on an output signal input from the position sensor 100. The grounding unit 303 is a circuit unit that sets a ground voltage of the position sensor 100. In addition, the controller 300 may also be configured as an electronic control unit (ECU).

[0070] The position sensor 100 includes a detection unit 122 and a signal processing unit 123. The detection unit 122 is provided in the sensor chip 110. The signal processing unit 123 is provided in the processing circuit chip 109. The detection unit 122 and the signal processing unit 123 operate based on a power supply voltage and a ground voltage supplied from the controller 300.

[0071] The detection unit 122 generates a plurality of detection signals corresponding to a plurality of ranges along the moving direction of the shaft 200 and having different phase differences based on the change in the magnetic field received from the shaft 200 as the shaft 200 moves. The plurality of ranges along the moving direction of the shaft 200 are not arranged in parallel along the moving direction of the shaft 200, but are arranged in series in one direction along the moving direction of the shaft 200.

[0072] like Fig.10 As shown, the detection unit 122 includes three element pairs, namely, a first magnetoresistive element pair 124 , a second magnetoresistive element pair 125 , and a third magnetoresistive element pair 126 , whose resistance values ​​change with the movement of the protrusion 201 .

[0073] In the moving direction of the protrusion 201, the three element pairs are respectively arranged in a manner that the second magnetoresistive element pair 125 is located between the first magnetoresistive element pair 124 and the third magnetoresistive element pair 126. That is, the second magnetoresistive element pair 125 is arranged in a manner sandwiched by the first magnetoresistive element pair 124 and the third magnetoresistive element pair 126. In addition, a bias magnetic field along the central axis of the magnet 106 is applied to the second magnetoresistive element pair 125. On the other hand, a bias magnetic field that is drawn into the end of the magnet 106 is applied to the first magnetoresistive element pair 124 and the third magnetoresistive element pair 126.

[0074] Each magnetoresistive element pair 124 to 126 is configured as a half-bridge circuit in which two magnetoresistive elements are connected in series between a power supply and a ground. Each magnetoresistive element pair 124 to 126 detects a change in resistance value when the two magnetoresistive elements are affected by a magnetic field as the protrusion 201 moves. In addition, each magnetoresistive element pair 124 to 126 outputs the voltage at the midpoint of the two magnetoresistive elements as a waveform signal based on the change in resistance value. In addition, in a configuration in which each magnetoresistive element pair 124 to 126 is driven by a current source, the voltage across each magnetoresistive element pair 124 to 126 is a waveform signal.

[0075] In addition, the detection unit 122 includes first to fourth operational amplifiers (not shown) in addition to the magnetoresistive element pairs 124 to 126. If the midpoint potential of the midpoint of the first magnetoresistive element pair 124 is defined as V1, and the midpoint potential of the midpoint of the second magnetoresistive element pair 125 is defined as V2, the first operational amplifier is a differential amplifier configured to calculate V1-V2 and output the result as R1. In addition, if the midpoint potential of the midpoint of the third magnetoresistive element pair 126 is defined as V3, the second operational amplifier is a differential amplifier configured to calculate V2-V3 and output the result as R2.

[0076] The third operational amplifier is a differential amplifier configured as follows: the midpoint potential V1 is input from the midpoint of the first magnetoresistive element pair 124, and the midpoint potential V3 is input from the midpoint of the third magnetoresistive element pair 126, and V1-V3 is calculated and the result is output as S1. For example, the signal S1 is a waveform signal whose amplitude becomes maximum at the center of the protrusion 201 of the shaft 200 in the moving direction and whose amplitude becomes minimum at a position away from the protrusion 201.

[0077] The fourth operational amplifier is a differential amplifier configured as follows: R1 (= V1 - V2) is input from the first operational amplifier, and R2 (= V2 - V3) is input from the second operational amplifier, R2 - R1 is calculated, and the result is output as S2 (= (V2 - V3) - (V1 - V2)). The signal S2 is a signal of a waveform corresponding to the concave-convex structure of the protrusion 201 of the shaft 200. For example, the signal S2 is a signal of a waveform in which the amplitude becomes maximum at the edge portion on the side where the protrusion 201 of the shaft 200 switches from concave to convex, and the amplitude becomes minimum at the edge portion on the other side where the protrusion 201 switches from convex to concave. The signal S2 is a signal of a waveform having a phase difference with respect to the signal S1.

[0078] Thus, the detector 122 is configured to generate and acquire the signal S1 (= V1 − V3 ) and the signal S2 (= ( V2 − V3 ) − ( V1 − V2 )) based on the outputs of the magnetoresistive element pairs 124 to 126 . The detector 122 outputs the signal S1 and the signal S2 to the signal processing unit 123 as detection signals.

[0079] Fig. 9 The signal processing unit 123 obtains each detection signal from the detection unit 122, compares each detection signal with a threshold value, and determines the position of the shaft 200 as a position in a certain range of multiple ranges in the shaft 200 based on a combination of the magnitude relationship between each detection signal and the threshold value. In addition, the signal processing unit 123 outputs the position of the shaft 200 to the controller 300. The signal processing unit 123 includes a processing unit 127 and an output circuit unit 128.

[0080] The processing unit 127 receives the detection signals from the detection unit 122 and specifies the position of the protrusion 201 based on the detection signals. To this end, the processing unit 127 has a common threshold value for the detection signals.

[0081] Furthermore, the processing unit 127 compares the signals S1 and S2 as detection signals with the threshold value. The processing unit 127 determines that the signal S1 and S2 are larger than the threshold value as Hi, and determines that the signal S1 and S2 are smaller than the threshold value as Lo. In addition, the processing unit 127 determines which range of the shaft 200 the detection unit 122 has detected based on the combination of Hi / Lo of the signals S1 and S2.

[0082] Specifically, if Fig.10 As shown in FIG. 1 , when the signal S1 is Lo and the signal S2 is Hi, the detection unit 122 detects a range of the shaft 200 that is on the left side of the figure relative to the protrusion 201. That is, the processing unit 127 determines the position of the shaft 200. The state of the shaft 200 when the position of the range is determined is referred to as "state A".

[0083] Similarly, when signal S1 is Hi, detection unit 122 detects the range of protrusion 201 in shaft 200. In this case, Hi / Lo of signal S2 is not limited. Therefore, the state of shaft 200 when the position of the range is determined is set to "state B".

[0084] Furthermore, when the signal S1 is Lo and the signal S2 is Lo, the detection unit 122 detects a range of the shaft 200 that is on the right side of the drawing relative to the protrusion 201. The state of the shaft 200 when the position of the range is determined is referred to as "state C". In this way, the processing unit 127 determines the position of the shaft 200 as a position in a range among a plurality of ranges along the moving direction of the shaft 200.

[0085] The output circuit unit 128 is a circuit unit that outputs a position signal indicating one of the above-mentioned states A to C to the controller 300 based on the determination result of the processing unit 127. First, the output circuit unit 128 obtains information on the states A to C determined based on the detection signal from the processing unit 127. Then, the output circuit unit 128 outputs a position signal of a value corresponding to the determined position range among discrete values ​​set for a plurality of ranges to the controller 300.

[0086] In this embodiment, the discrete position signal is a voltage signal with different voltage values. H , State B is V M , State C is V L In this way, the voltage values ​​representing the states A to C are set as discrete values ​​so that the voltage values ​​in the states A to C do not overlap. The magnitude relationship of the voltage values ​​is V H >V M >V L Since the discrete value does not need to be repeated in each state A to C, the discrete value may be set to a voltage value within a specified voltage range. The specified voltage range may be the same in each state A to C, such as within 1V, or may be different, such as within 1V in state A but within 2V in state B.

[0087] like Fig.10 As shown, when the protrusion 201 moves along the moving direction of the shaft 200, the position signal becomes a discrete voltage value in a step shape. In addition, there is a case where the voltage value of the position signal rises and falls instantaneously due to noise and reaches a voltage value representing another state. However, the control unit 302 of the controller 300 can basically eliminate the influence of noise by reading the voltage value for a predetermined time. That is, the position sensor 100 can output a position signal with high noise resistance. The above is the structure of the position sensor 100 of this embodiment.

[0088] The control unit 302 of the controller 300 receives the position signal from the position sensor 100 and uses it for desired control, such as turning on and off the parking light of the instrument panel of the vehicle, controlling whether to allow or not allow other controls according to whether the gear is in the parking position, controlling not to use the position sensor 100 when the position sensor 100 fails, and controlling the lighting of a fault light.

[0089] In addition, the control unit 302 may receive a signal other than the position signal. This signal is a signal that is not originally generated as an output of the position sensor 100. In this case, a fault other than the position sensor 100 is considered to be the cause. For example, a fault in a communication device such as the harness 400, etc. Therefore, the controller 300 can detect a fault in the communication device.

[0090] As a modified example, Fig.11 As shown in FIG. 1 , four states can be determined based on the detection signal. The case where signal S1 is Lo and signal S2 is Hi is set to "state A", the case where signal S1 is Hi and signal S2 is Hi is set to "state B", the case where signal S1 is Hi and signal S2 is Lo is set to "state C", and the case where signal S1 is Lo and signal S2 is Lo is set to "state D". In this case, as long as Fig.11 As shown in the figure, the four states are set to four discrete voltage values ​​(V H >V M1 >V M2 >V L )

[0091] As a modified example, Fig.12 As shown, three states can be determined based on the first magnetoresistive element pair 124 and the second magnetoresistive element pair 125. In this case, the processing unit 127 generates and obtains the signal S3 (= V1-V2) and the signal S4 (= V1+V2) based on the outputs of the magnetoresistive element pairs 124 and 125. Through such calculation processing, two detection signals with different phase differences can also be obtained.

[0092] Thus, the processing unit 127 determines that the case where the signal S3 is Lo and the signal S4 is Hi is "state A", the case where the signal S3 is Hi is "state B", and the case where the signal S3 is Lo and the signal S4 is Lo is "state C". In this case, the three states are represented as three discrete voltage values ​​(V H 、V M 、V L ) and output.

[0093] As a modified example, Fig.13 As shown in FIG. 1 , the processing unit 127 generates and obtains the signal S5 (= V1 - V3) and the signal S6 (= V2) based on the outputs of the three magnetoresistive element pairs 124 to 126. In this way, the three states can be determined based on the two element pairs of the first magnetoresistive element pair 124 and the second magnetoresistive element pair 125. The state determination in this modification is similar to Fig.12 same.

[0094] As a modified example, Fig.14 As shown, the detection unit 122 includes five element pairs, namely, a first magnetoresistive element pair 124, a second magnetoresistive element pair 125, a third magnetoresistive element pair 126, a fourth magnetoresistive element pair 129, and a fifth magnetoresistive element pair 130. Each of the magnetoresistive element pairs 124 to 126, 129, and 130 outputs midpoint potentials V1 to V5, respectively.

[0095] In this case, the processing unit 127 generates and obtains a signal S7 (= V4 - V5) and a signal S8 (= 2V2 - V1 - V3) based on the outputs of the magnetoresistive element pairs 124 to 126, 129, and 130. Fig.12 The example also determines three states.

[0096] As a modified example, Fig.15 As shown, the detection unit 122 has four magnetoresistive element pairs 124 to 126, 129. In this case, the processing unit 127 generates and obtains three signals S9 (= V1-V4), signal S10 (= 2V2-V1-V3) and signal S11 (= 2V3-V2-V4) based on the outputs of the four element pairs. In this way, three detection signals with different phase differences can be obtained based on the outputs of the four element pairs.

[0097] Then, the processing unit 127 determines the case where the signal S9 is Lo, the signal S10 is Hi, and the signal S11 is Hi as "state A", and determines the case where the signal S9 is Hi, the signal S10iHi, and the signal S11 is Hi as "state B". In addition, the processing unit 127 determines the case where the signal S9 is Hi, the signal S10 is Lo, and the signal S11 is Hi as "state C", and determines the case where the signal S9 is Hi, the signal S10 is Lo, and the signal S11 is Lo as "state D". Moreover, the processing unit 127 determines the case where the signal S9 is Lo, the signal S10 is Lo, and the signal S11 is Lo as "state E". In this case, as in the above, the five states are output as five discrete voltage values.

[0098] As a modified example, Fig.16 As shown, the detection unit 122 has three magnetoresistive element pairs 124 to 126. In addition, the processing unit 127 generates and obtains three signals S12 (= V1-V2), signal S13 (= V2-V3) and signal S14 (= 2V2-V1-V3) based on the outputs of the three element pairs. In this way, three detection signals with different phase differences can be obtained based on the outputs of the three element pairs.

[0099] Then, the processing unit 127 determines six states A to F by the combination of Hi / Lo of the three signals S12, S13, and S14, similarly to the above-mentioned modification. In this case, the six states are output as six discrete voltage values, similarly to the above-mentioned modification.

[0100] As a modified example, Fig.17As shown, the detection unit 122 has four magnetoresistive element pairs 124 to 126, 129. In addition, the processing unit 127 generates and obtains four signals S15 (= V1-V4), signal S16 (= V2-V3), signal S17 (= 2V2-V1-V3) and signal S18 (= 2V3-V2-V4) based on the outputs of the four element pairs. In this way, four detection signals with different phase differences can be obtained based on the outputs of the four element pairs.

[0101] Then, the processing unit 127 determines seven states A to G by the combination of Hi / Lo of the four signals S15, S16, S17, and S18, similarly to the above-mentioned modification. In this case, the seven states are output as seven discrete voltage values, similarly to the above-mentioned modification.

[0102] As a modified example, Fig.18 As shown, the detection unit 122 has five magnetoresistive element pairs 124 to 126, 129, and 130. In addition, the processing unit 127 generates and obtains four signals S19 (=V1-V3), signal S20 (=V3-V5), signal S21 (=V2-V4), and signal S22 (=2V3-V1-V5) based on the outputs of the five element pairs. In this way, four detection signals with different phase differences can be obtained based on the outputs of the five element pairs.

[0103] Then, the processing unit 127 determines eight states A to H by the combination of Hi / Lo of the four signals S19, S20, S21, and S22, similarly to the above-mentioned modification. In this case, the eight states are output as eight discrete voltage values, similarly to the above-mentioned modification.

[0104] As a modified example, Fig.19 As shown, the detection unit 122 has three magnetoresistive element pairs 124 to 126. In addition, the processing unit 127 generates and obtains two signals S23 (= V1 - V3) and signal S24 (= 2V2 - V1 - V3) based on the outputs of the three element pairs. In this way, two detection signals with different phase differences can be obtained based on the outputs of the three element pairs.

[0105] In addition, the processing unit 127 has a first threshold value and a second threshold value. The second threshold value is a value smaller than the first threshold value. Moreover, the processing unit 127 compares each signal S23, S24 with each threshold value. In this case, the processing unit 127 determines that the case where the signal is larger than the first threshold value is Hi, the case where the signal is between the first threshold value and the second threshold value is Mid, and the case where the signal is smaller than the second threshold value is Lo.

[0106] Therefore, the processing unit 127 determines that the case where the signal S23 is Lo and the signal S24 is Hi is "state A", determines that the case where the signal S23 is Mid and the signal S24 is Hi is "state B", and determines that the case where the signal S23 is Hi and the signal S24 is Hi is "state C". In addition, the processing unit 127 determines that the case where the signal S23 is Hi and the signal S24 is Mid is "state D", and determines that the case where the signal S23 is Hi and the signal S24 is Lo is "state E". Furthermore, the processing unit 127 determines that the case where the signal S23 is Mid and the signal S24 is Lo is "state F", and determines that the case where the signal S23 is Lo and the signal S24 is Lo is "state G".

[0107] In this way, the number of states that can be determined can be changed by using multiple thresholds. Of course, the threshold is not limited to two, and three or more thresholds can also be set. In this modified example, the seven states are output as seven discrete voltage values, just like the above.

[0108] As a modified example, Fig. 20 As shown, the detection unit 122 can also be configured to detect the change of the magnetic field caused by the movement of the shaft 200 through the three Hall elements 131 to 133 arranged on the magnet 120. In this case, the processing unit 127 generates and obtains two signals S25 (= V2) and signal S26 (= V1-V3) based on the outputs of the three Hall elements 131 to 133. In this way, two detection signals with different phase differences can also be obtained based on the outputs of the three Hall elements 131 to 133.

[0109] In this case, the processing unit 127 determines three states A to C by the combination of Hi / Lo of the two signals S25 and S26, similarly to the above-mentioned modification. In this case, the three states are output as three discrete voltage values, similarly to the above-mentioned modification.

[0110] As a modified example, Fig.21 As shown, the shaft 200 may also be formed in a shape such that a cylinder is inserted into a quadrilateral block. Fig. 22 As shown in FIG. 2 , the detection object may not be the shaft 200 but a plate member 202 having a quadrilateral block disposed on the plane portion of the quadrilateral plate. Fig.23 As shown, the detection object may be a fan member 203 in which a quadrilateral block is provided on a flat surface portion of a fan-shaped plate.

[0111] That is, the detection object only needs to be formed in the following manner: a reference portion is provided between the first moving portion and the second moving portion, and the structural changes when transitioning from the first moving portion to the reference portion and when transitioning from the second moving portion to the reference portion are the same. Figure 21 to Figure 23In the example shown, the reference portion protrudes relative to the first movable portion and the second movable portion. In addition, the transition from the first movable portion to the reference portion and the transition from the second movable portion to the reference portion correspond to the transition from the concave state to the convex state. In this way, the detection object can be formed into a shape that divides the detection range into a plurality of ranges.

[0112] As described above, in this embodiment, the position sensor 100 is characterized in that a certain range among a plurality of ranges of the shaft 200 as a detection object is determined, and a position signal corresponding to the position of the determined range is output. In this configuration, since the detection unit 122 detects the position under the influence of the magnetic field from the shaft 200, it is not necessary to set a magnet as a detection object on the protrusion 201 of the shaft 200. Therefore, the number of processing, assembly man-hours, and number of parts of the detection object will not increase, and the detection position error caused by the magnet of the detection object will not occur.

[0113] In addition, the signal processing unit 123 is configured to detect the position of the protrusion 201, which is the detection object, as the state of the shaft 200. Therefore, the detection position error caused by the signal offset of the position signal and the A / D conversion error included in the position signal does not occur. Therefore, the occurrence of the detection position error can be suppressed.

[0114] Furthermore, the signal processing unit 123 is configured to output each state as a discrete voltage value. Therefore, since a reading margin can be set on the controller 300 side, each state will not be misjudged even when noise overlaps, and the noise resistance performance is high. In this way, the detection position error caused by noise can be reduced, and the robustness against the detection position error can be improved. Therefore, the accuracy of the output of the position sensor 100 can be ensured.

[0115] In addition, the shaft 200, the plate member 202, and the fan member 203 correspond to the detection object, and the controller 300 corresponds to the external device.

[0116] (Second Embodiment)

[0117] In this embodiment, the parts different from the first embodiment are described. Fig.24 As shown, the shaft 200 has a recessed portion 204 that is partially recessed in the radial direction. In this case, the processing unit 127 can generate the signal S1 and the signal S2 based on the detection signals of the magnetoresistive element pairs 124 to 126 and determine the three states.

[0118] In this case, if Fig.25As shown in FIG. 1 , signal S27 (= V1-V3) is a waveform signal in which the amplitude becomes minimum at the center of the moving direction of the recessed portion 204 of the shaft 200 and the amplitude becomes maximum at a position away from the recessed portion 204. On the other hand, signal S28 (= 2V2-V1-V3) is a waveform signal in which the amplitude becomes minimum at the edge portion of the recessed portion 204 of the shaft 200 on the side where the convex portion is switched to the concave portion and the amplitude becomes maximum at the edge portion on the other side where the concave portion is switched to the convex portion. That is, for example, with respect to Fig.10 The example shown has the signal inverted.

[0119] Then, the processing unit 127 determines three states A to C by the combination of Hi / Lo of the two signals S27 and S28, similarly to the first embodiment. In this case, the processing unit 127 outputs the three states as three discrete voltage values, similarly to the above.

[0120] As a modified example, Fig.26 As shown, the four states A to D can also be determined by the combination of the two signals S27 and the Hi / Lo of the signal S28. In this case, the four states are output as four discrete voltage values ​​as described above. In addition, the number of signals can be changed or the number of determined states can be changed as in the first embodiment.

[0121] As a modified example, Fig. 27 As shown in FIG. 1 , the detection object may also be a member having a window portion 205 provided on the plate member 202. Fig.28 As shown, the detection object may also be a fan part 203 provided with a window 205. Fig.24 , Fig. 27 , Fig.28 In the example shown, the reference portion is recessed relative to the first movable portion and the second movable portion. In addition, the transition from the first movable portion to the reference portion and the transition from the second movable portion to the reference portion correspond to the transition from the convex state to the concave state. In this way, the detection object can be formed into a shape that divides the detection range into a plurality of ranges.

[0122] (Third Embodiment)

[0123] In this embodiment, the parts different from the first and second embodiments are described. In this embodiment, the output circuit unit 128 outputs the pulse signal with different pulse widths as a discrete value signal to the controller 300. That is, the discrete value signal is a PWM signal. The discrete value is the value of the pulse width, the period of the signal, the duty cycle, etc.

[0124] like Fig.29As shown, for example, the pulse width of the signal corresponding to state A is set to be the smallest, and the pulse width of the signal corresponding to state C is set to be the largest. The pulse width of the signal corresponding to state B is set between the pulse widths of the signals corresponding to states A and C. The resistance to noise can be improved in the same manner as in the first embodiment.

[0125] (Other embodiments)

[0126] The configuration of the position sensor 100 shown in the above embodiments is an example and is not limited to the configuration shown above. Other configurations that can realize the present disclosure can also be adopted. For example, the use of the position sensor 100 is not limited to vehicles, but can also be widely used in industrial robots, manufacturing equipment, etc. as a device for detecting the position of a movable part.

[0127] The present disclosure is described in accordance with the embodiments, but it is understood that the present disclosure is not limited to the embodiments and configurations. The present disclosure also includes various modifications and modifications within the equivalent range. In addition, various combinations and methods, and other combinations and methods that only include one element, more than one element, or less than one element in them also fall within the scope and thought of the present disclosure.

Claims

1. A position sensor, characterized in that: have: A detection unit that generates a plurality of detection signals having different waveforms and phase differences, corresponding to a plurality of ranges arranged in one direction along a moving direction of the detection object, based on changes in a magnetic field received from the detection object as the detection object composed of a magnetic body moves; as well as a signal processing unit, which obtains the plurality of detection signals from the detection unit, compares the plurality of detection signals with a threshold value, and determines the position of the detection object as a position of a certain range among the plurality of ranges based on a combination of magnitude relationships between the plurality of detection signals and the threshold value; The detection object is formed in the following manner: it has only one reference part and a moving part different from the reference part, the reference part is provided between a first moving part and a second moving part as the moving part, and the structural changes when transitioning from the first moving part to the reference part and when transitioning from the second moving part to the reference part are the same, The signal processing unit outputs a position signal corresponding to the range of the position of the detection object determined by the signal processing unit, among the discrete values ​​set for the multiple ranges, to an external device based on the transition from the moving part of the detection object to the reference part of the detection object.

2. The position sensor according to claim 1, wherein: The reference portion of the detection object is a protrusion that protrudes relative to the moving portion of the detection object.

3. The position sensor according to claim 1, wherein: The reference portion of the detection object is a recessed portion that is recessed relative to the moving portion of the detection object.

4. The position sensor according to claim 1, wherein: The detection unit includes a plurality of magnetoresistive element pairs configured as a half-bridge circuit and arranged away from each other, and generates the plurality of detection signals as outputs of a full-bridge circuit by combining outputs of the plurality of magnetoresistive element pairs.

5. The position sensor according to claim 1, wherein: The plurality of ranges are a plurality of detection areas arranged in one direction along the moving direction of the detection object.

6. The position sensor according to claim 1, wherein: The discrete-value position signal is a voltage signal having different voltage values.

7. The position sensor according to claim 1, wherein: The discrete-value position signal is a pulse signal having different pulse widths.

8. The position sensor according to claim 1, wherein: The detection unit includes a plurality of magnetoresistive element pairs whose resistance values ​​change as the detection object moves.

9. The position sensor according to claim 8, wherein: The detection unit generates the plurality of detection signals based on outputs of the plurality of magnetoresistive element pairs.

10. The position sensor according to any one of claims 1 to 9, wherein: The detection object is a movable member that moves in conjunction with the movement of the gear position of the vehicle.

11. The position sensor according to claim 2, wherein: The protrusion is a quadrilateral block.

12. The position sensor according to claim 1, wherein: The moving portion is a cylinder extending in the moving direction.

13. The position sensor according to claim 3, wherein: The recessed portion is a window portion.

14. The position sensor according to claim 1, wherein: The reference portion is a cylinder extending in the moving direction.

15. The position sensor according to claim 1, wherein: The reference portion and the moving portion are cylinders extending in the moving direction, and the reference portion has a smaller diameter than the moving portion.

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