JP2016099191A - Rotation angle detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable simplification of a wire harness, and accurately perform correctness or wrongness of a detection signal in a rotation angle detection device in which a rotation angle signal of a shaft member is detected in accordance with a relative rotation of a magnet member with respect to a pair of magnetoelectric conversion elements and the detected rotation angle is output to an electronic control unit.SOLUTION: A rotation angle detection device comprises: a first processing circuit 110 that is connected to one (101) of a pair of magnetoelectric conversion elements; a second processing circuit 120 that is connected to the other (102) of the pair of magnetoelectric conversion elements; a comparison circuit 130 that compares a computation result of the second processing circuit and a computation result of the first processing circuit; and a single output circuit 140 that outputs a signal in accordance with a comparison result of the comparison circuit and computation results of the first and second processing circuits. A single output signal line LO of the output circuit is electrically connected to an electronic control unit ECU.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a rotation angle detection device, and more particularly to a rotation angle detection device that detects a rotation angle of a shaft member according to relative rotation of a magnet member with respect to a magnetoelectric conversion element.

  Conventionally, for example, a contactless rotation angle detection device that detects the rotation angle of a shaft member in order to detect the operation amount of a brake pedal of an automobile is known. For example, the shaft member is opposed to a magnetoelectric conversion element. It has the magnet member arrange | positioned and it is comprised so that the rotation angle of a shaft member may be detected according to relative rotation with respect to the magnetoelectric conversion element of this magnet member. For example, in Patent Document 1 below, “a housing provided with a magnetic sensor, a rotating member including a magnet facing the magnetic sensor and rotatable with respect to the housing, and a rotating operation together with the operated member” A rotation angle detection device configured to detect a swing angle of the operated member by a change in an output signal from the magnetic sensor that rotates relative to the magnet. (Described in paragraph [0001] of Patent Document 1).

  In addition, the following Patent Document 2 states that “the X and Y magnetoelectric transducers rotate the disk magnets magnetized in the radial direction and the horizontal magnetic fields generated by the disk magnets are arranged at 90 degrees to each other. There is disclosed a “rotation angle sensor for sensing the rotation angle from the output values of the X and Y magnetoelectric conversion elements” (described in paragraph [0016] of Patent Document 2), and a Hall element is used as the magnetoelectric conversion element. (Described in the same paragraph [0020]).

JP 2007-139458 A JP 2007-93280 A

  In the above-mentioned Patent Document 1, an object is to “provide a rotation angle detection device in which the detection accuracy of the rotation angle is not easily lowered even when a stress accompanied by a tilting component is applied to the shaft member via the operated member”. (Described in paragraph [0005] of Patent Document 1), "The rotating member and the shaft member are linked to each other so that the rotation shaft cores can tilt, and regardless of the tilt of the shaft member, A rotation angle detecting device is proposed (described in paragraph [0006]), in which a centering mechanism is provided to hold the rotation axis of the rotating member coaxially with the fixed axis of the housing. It can be used as a rotation angle detection device for detecting the swing angle of a member to be operated that is rotated by a steering pedal or the like ”(described in the same paragraph [0030]). On the other hand, in Patent Document 2, “the number of magnetoelectric conversion elements is reduced in cost and the structure can be simplified, and the magnetoelectric conversion element can be arranged at a position off the center of the disk magnet. The object is to provide a rotation angle sensor capable of suppressing an angular error due to a relative positional deviation with respect to a disc magnet "(described in paragraph [0015] of Patent Document 2), and the arrangement of magnetoelectric transducers is specified. (Described in the same paragraph [0016]).

  The specific configuration of the rotation angle detection device described in Patent Document 1 is disclosed in FIG. 2 of Patent Document 1 and described in paragraphs [0013] to [0016]. The housing includes a magnetic body, a housing body having a magnetic sensing unit, a connector portion, and a housing portion, and a cover member that closes the housing portion so as to protrude from the housing body. A pair of Hall ICs are housed in the boss portion by insert molding, and the shaft member is pivotally supported by a bearing formed on the cover member.

  In the above-mentioned patent document 2, as disclosed in FIG. 1 and described in paragraphs [0020] and [0021], it is arranged so as to face X and Y Hall elements that are magnetoelectric conversion elements, The disk magnet magnetized in the direction is rotated, the horizontal magnetic field generated thereby is sensed by the X and Y Hall elements arranged at 90 degrees, and the rotation angle is obtained from these output values. ing.

  The conventional rotation angle detection device is configured, for example, as a rotation sensor shown in FIG. 10, and is electrically connected to an external electronic control unit ECU via respective output signal lines from the magnetic sensors 1 and 2 having magnetoelectric conversion elements. In general, an analog signal is output. For this reason, two output signal lines are required, and a total of four signal lines including a power line and a ground line are required. Moreover, since the correctness / incorrectness determination of the detection (output) signal is performed only by the electronic control unit ECU, there is a possibility that it is determined as an erroneous detection due to an erroneous signal caused by external noise or the like, and a separate erroneous determination countermeasure is required.

  Therefore, the present invention enables simplification of the wire harness in the rotation angle detection device in which the rotation angle signal of the shaft member is detected according to the relative rotation of the magnet member with respect to the pair of magnetoelectric transducers and is output to the electronic control device. It is another object of the present invention to provide a rotation angle detection device that can reliably determine whether a detection signal is correct or incorrect.

  In order to achieve the above object, the present invention includes a pair of magnetoelectric conversion elements and a magnet member disposed on a shaft member facing the pair of magnetoelectric conversion elements, and the pair of magnetoelectric conversions of the magnet member. In the rotation angle detection device in which a rotation angle signal of the shaft member is detected by the pair of magnetoelectric conversion elements according to relative rotation with respect to the element, and the rotation angle signal is output to an electronic control device, the pair of magnetoelectric conversion elements A first processing circuit connected to one side, a second processing circuit connected to the other of the pair of magnetoelectric transducers, an operation result of the second processing circuit, and an operation result of the first processing circuit And a single output circuit that outputs a signal according to the comparison result of the comparison circuit and the calculation results of the first and second processing circuits, and a single output circuit of the output circuit. The output signal line is electrically connected to the electronic control unit. It is obtained by a configuration to be continued. In addition, it is good also as a structure electrically connected to the said electronic control apparatus via a power supply line and a ground line with the said output signal line.

  In the above rotation angle detection device, the pair of magnetoelectric transducers, the first processing circuit, the second processing circuit, the comparison circuit, and the output circuit can be configured by a single IC chip.

  In the rotation angle detection device, a housing that houses the pair of magnetoelectric conversion elements, a support member that is joined to the housing and rotatably supports the shaft member, and the pair of magnetoelectric conversion elements are electrically connected A connector member to be connected, and the housing is formed integrally with the main body portion in which an element chamber accommodating at least the pair of magnetoelectric conversion elements is formed, and is joined to the connector member. It is good to have the structure which has a joined part to be joined, and the said connector member is liquid-tightly fitted and joined with respect to this joined part.

  Further, the pair of magnetoelectric transducers, the first processing circuit, the second processing circuit, the comparison circuit, and the output circuit are configured by a single IC chip, and the IC chip is accommodated in the element chamber. Good. The housing may be configured to have a magnet chamber formed in the main body portion separately from the element chamber, and to be joined to the support member in a state where the magnet member is accommodated in the magnet chamber.

  Since this invention is comprised as mentioned above, there exist the following effects. That is, in the rotation angle detection device of the present invention, the first processing circuit connected to one of the pair of magnetoelectric conversion elements, the second processing circuit connected to the other of the pair of magnetoelectric conversion elements, and the second A comparison circuit for comparing the calculation result of the first processing circuit and the calculation result of the first processing circuit, and a single signal for outputting a signal corresponding to the comparison result of the comparison circuit and the calculation results of the first and second processing circuits. Output circuit, and a single output signal line of the output circuit is configured to be electrically connected to the electronic control device, so that the electronic control device is connected to the electronic control device via the output signal line, the power supply line, and the ground line. Even when it is configured to be electrically connected, the entire wire harness can be simplified. In addition, when a detection error occurs in one of the pair of magnetoelectric transducers, it can be determined that the detection circuit has detected the error, and a signal indicating the error detection can be supplied from the output circuit to the electronic control device. In addition, the correctness / incorrectness determination can be performed also in the electronic control device itself, so that the correctness / incorrectness determination of the detection signal can be performed reliably.

  In the above rotation angle detection device, if the pair of magnetoelectric transducers, the first processing circuit, the second processing circuit, the comparison circuit, and the output circuit are configured with a single IC chip, not only the wire harness can be simplified. Therefore, the entire apparatus can be reduced in size.

  In the above rotation angle detection device, a housing that houses a pair of magnetoelectric conversion elements, a support member that is joined to the housing and rotatably supports a shaft member, and a connector that is electrically connected to the pair of magnetoelectric conversion elements And a housing having a main body portion in which an element chamber accommodating at least a pair of magnetoelectric conversion elements is formed, and a joint portion formed integrally with the main body portion and joined to the connector member, If it is set as the structure by which a connector member is liquid-tightly fitted and joined with respect to a junction part, the waterproofness with respect to a magnetoelectric conversion element can be ensured easily and appropriately with a simple structure.

  Further, if the pair of magnetoelectric conversion elements, the first processing circuit, the second processing circuit, the comparison circuit, and the output circuit are configured by a single IC chip and the IC chip is accommodated in the element chamber, the IC A small device can be obtained while ensuring waterproofness to the chip. Further, if the housing has a magnet chamber formed in the main body portion separately from the element chamber, and the magnet member is accommodated in the magnet chamber, the magnet can be rotated. Since the IC chip can be completely separated from the member, it is possible to reliably ensure waterproofness.

It is sectional drawing of the rotation angle detection apparatus which concerns on one Embodiment of this invention. It is a top view which shows the relationship between the magnet member provided to one Embodiment of this invention, and a magnetoelectric conversion element. It is a circuit diagram which shows the structure of the IC chip provided to one Embodiment of this invention. It is sectional drawing which isolate | separates and shows the housing and support member which are provided to one Embodiment of this invention. It is a top view which shows the supporting member provided to one Embodiment of this invention. It is a top view which shows the state which mounted | wore the support member with which it uses for one Embodiment of this invention with the shaft member. It is a perspective view which shows the shaft member provided to one Embodiment of this invention. It is a perspective view which shows the rotation angle detection apparatus which concerns on one Embodiment of this invention. It is a perspective view which decomposes | disassembles and shows the rotation angle detection apparatus which concerns on one Embodiment of this invention. It is a circuit diagram which shows the structural example of the conventional rotation sensor.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 to FIG. 9 relate to an embodiment of the present invention, and a non-contact type that detects the rotation angle of the shaft member 2 according to the relative rotation of the magnet member 20 with respect to a pair of magnetoelectric transducers configured in the IC chip 10. The rotation angle detecting device is used for detecting the operation amount of an external mechanism, for example, a brake pedal. A pair of magnetoelectric conversion elements denoted by 101 and 102 in FIG. 3 is constituted by a pair of Hall ICs, for example, and is constituted in the IC chip 10 together with other elements and the like. As shown in FIG. 1, a support member 3 that rotatably supports the shaft member 2 is joined to the housing 1 that houses the IC chip 10, and one end of a coil spring that constitutes the return spring 4 is connected to the shaft member 2. The other end is locked to the support member 3. For example, when the connector member 5 of the waterproof connector is joined to the housing 1, the IC chip 10 is electrically connected to the external electronic control unit ECU via the connector member 5, and the IC chip 10 is sealed from the outside. The When the drive lever 6 is fixed to the shaft member 2 and disposed so as to engage with the pedal lever PL, a brake pedal sensor is configured. The structure of the device is shown in FIGS. 1 and 4 to 4. This will be described later with reference to FIG.

  In the present embodiment, a parallel magnetic field is formed by the above-described magnet member 20 as shown by a broken line arrow in FIG. When the magnet member 20 is driven to rotate about the axis of the shaft member 2, the parallel magnetic field generated by the magnet member 20 is relatively relative to the IC chip 10 at the fixed position, as indicated by the dashed line arrow in FIG. For example, the X-direction component Bx and the Y-direction component By of the magnetic field intensity B when the rotation angle θ is reached are detected by the IC chip 10. Thus, a signal (rotation angle signal) proportional to the magnetic field direction is output from the IC chip 10, and the rotation angle is calculated by the electronic control unit ECU shown in FIGS.

  In the IC chip 10, as shown in FIG. 3, the first processing circuit 110 connected to one (101) of a pair of magnetoelectric conversion elements and the other (102) of the pair of magnetoelectric conversion elements are connected. Second processing circuit 120, a comparison circuit 130 for comparing the calculation result of the second processing circuit 120 with the calculation result of the first processing circuit 110, the comparison result of the comparison circuit 130, and the first and A single output circuit 140 that outputs a signal according to the calculation results of the second processing circuits 110 and 120 is configured, and a single output signal line LO of the output circuit 140 is electrically connected to the electronic control unit ECU. Thus, a digital signal including two detection results by the magnetoelectric conversion elements 101 and 102 and a comparison result between the two detection results is output. In the first and second processing circuits 110 and 120 shown in FIG. 3, 111 and 121 are amplifiers, 112 and 122 are analog-to-digital converters, 113 and 123 are digital signal processing devices, 114 and 124 are memories, and B Represents a power source and is connected to a Hall IC constituting the magnetoelectric transducers 101 and 102, respectively. Here, GND represents ground, LG represents a ground line, LB represents a power supply line, and LO represents an output signal line.

  In the output circuit 140, communication based on a digital output protocol is performed. For example, as shown in a dashed-dotted frame in FIG. 3, synchronization information and status information regarding the two magnetoelectric transducers 101 and 102 for each message period (mp). The data words 1 and 2 in which the calculation values 1 and 2 as the calculation results of the first and second processing circuits 110 and 120 are stored, and the information on the correctness / incorrectness determination (comparison result) are transmitted to the electronic control unit ECU. . That is, information for two (conventional) output signals can be transmitted by a single output signal line LO.

  As described above, in the present embodiment, the output circuit 140 is electrically connected to the electronic control unit ECU via the output signal line LO, the power supply line LB, and the ground line LG. The output is configured to be supplied to the electronic control unit ECU. Accordingly, the number of the wire harnesses is three, that is, the output signal line LO, the power supply line LB, and the ground line LG, which is simplified as compared with the conventional four. In the present embodiment, the pair of magnetoelectric transducers 101 and 102, the first processing circuit 110, the second processing circuit 120, the comparison circuit 130, and the output circuit 140 are configured by a single IC chip 10. The IC chip 10 is accommodated in the housing 1 shown in FIG. Thus, if a detection error occurs in any one of the pair of magnetoelectric transducers 101 and 102, it is determined to be erroneous detection in the comparison circuit 130, and the erroneous detection is indicated from the output circuit 140 to the electronic control unit ECU. A signal is supplied. In addition, since the correctness / incorrectness determination is performed in the electronic control unit ECU as before, the correctness / incorrectness determination can be reliably performed.

  4 to 9 show the structure of the rotation angle detection device together with FIG. 1, and each component will be specifically described below. First, the housing 1 is made of a synthetic resin, and has a main body 1a and a joint 1b as shown in FIGS. 1 and 4, and an element chamber SC is formed in the main body 1a, and at least the IC chip 10 is accommodated. Has been. The main body 1a is formed with a magnet chamber MC that is separated from the element chamber SC. The main body 1a is accommodated in a position facing the IC chip 10 in the magnet chamber MC. The part 1a is joined to the support member 3 made of synthetic resin. The joint portion 1b is formed integrally with the main body portion 1a, and is configured such that the element chamber SC communicates with the external space only through the joint portion 1b. Therefore, when the connector member 5 is liquid-tightly fitted to the joint 1b, the element chamber SC becomes a sealed space. The housing 1 of the present embodiment has a cylindrical portion 1c that integrally extends from the main body portion 1a. For example, when laser welding is performed over the entire circumference of the cylindrical portion 1c, the cylindrical portion 1c is supported by the support member 3. The magnet chamber MC is shielded from the external space.

  On the other hand, as shown in FIGS. 5 and 6, the support member 3 is formed with a bearing portion 3 a that rotatably supports the shaft member 2, and an annular recess 3 b is formed therearound. An annular standing wall 3c is formed around the annular recess 3b, and the standing wall 3c is configured to be fitted to the inner peripheral surface of the cylindrical portion 1c of the housing 1. A plurality of (four in this embodiment) projections 3d are formed to extend from the standing wall 3c for positioning when the cylindrical portion 1c and the standing wall 3c are fitted, and these are provided on the inner peripheral surface of the cylindrical portion 1c. A recess 1d is formed to fit into the. Further, in the annular recess 3b, a locking projection 3e having an arc shape in plan view is formed to extend in order to lock the end 4a of the return spring 4. Further, a pair of flange portions 3f and 3f extending in a direction away from each other are formed on the outside from the standing wall 3c, and attachment holes 3g and 3g are formed, respectively.

  As shown in FIG. 7, in the shaft member 2, the disc portion 2a and the shaft portion 2b are integrally formed of synthetic resin, and the magnet member 20 is embedded in the disc portion 2a. A so-called two-plane engaging portion 2c is formed at the tip of the shaft portion 2b, and is configured to be engageable with a two-surface engaging hole 6c (shown in FIG. 9) formed in the drive lever 6. ing. Further, an arc-shaped locking projection 2e is formed on the lower surface of the disk portion 2a of the shaft member 2 so as to lock the end 4b of the return spring 4, and the locking projection 3e of the support member 3 is extended. On the other hand, the positional relationship shown in FIG.

  That is, the drive lever 6 has an extending portion 6a that extends in the radial direction of the shaft member 2, and an engaging portion 6b that extends parallel to the shaft of the shaft member 2 and engages with an external mechanism (pedal lever PL). , One end of the extending portion 6a is fixed to the shaft member 2 (by engagement of the engaging hole 6c and the engaging portion 2c), the other end of the extending portion 6a extends in the radial direction of the shaft member 2, and a return spring. The shaft member 2 is rotationally driven against the urging force 4.

  The magnet member 20 has a rectangular parallelepiped permanent magnet 21 disposed on a plane orthogonal to the axis of the shaft portion 2b, and the rectangular permanent magnet 21 has a direction orthogonal to the axis of the shaft portion 2b. A groove 21a is formed in the groove. The groove 21a is formed on the surface opposite to the surface facing the IC chip 10, includes the center of one surface of the rectangular parallelepiped, and extends in parallel with the side surface on the short side. The width is set to one third of the length on the long side. The permanent magnet 21 is magnetized along the longitudinal direction of the groove 21a.

  As described above, the IC chip 10 in the housing 1 has a pair of magnetoelectric transducers (indicated by 101 and 102 in FIG. 3), and changes according to the rotation of the shaft member 2 and, consequently, the rotation angle of the magnet member 20. A change in the angle of the magnetic field due to the permanent magnet 21 is detected by a pair of magnetoelectric transducers, and a voltage output corresponding to the magnetic field angle is supplied to the electronic control unit ECU via the connector member 5.

  The assembly process of the above rotation angle detection device will be described with reference to FIG. First, the return spring 4 is accommodated in the annular recess 3b of the support member 3, and its end 4a is locked to the locking projection 3e. Subsequently, the shaft portion 2b of the shaft member 2 is accommodated in the bearing portion 3a of the support member 3, and the end portion 4b of the return spring 4 is locked to the locking protrusion 2e of the shaft member 2, so that the annular standing wall 3c. When the disc portion 2a of the shaft member 2 is accommodated therein, the state shown in the lower part of FIG. 4 is obtained, and the housing 1 shown in the upper part of FIG. That is, each recess 1d formed in the cylindrical portion 1c of the housing 1 is fitted into each projection 3d formed in the standing wall 3c of the support member 3, and the cylindrical portion 1c is fitted in a predetermined position with respect to the standing wall 3c. Then, laser welding is performed over the entire circumference of the cylindrical portion 1c. As a result, the housing 1 is tightly joined to the support member 3, and the magnet chamber MC shown in FIG. 3 is formed.

  Next, the IC chip 10 is accommodated in the main body 1 a of the housing 1 and held at a position facing the IC chip 10. In the main body 1a, the connector member 5 is electrically connected to the pair of magnetoelectric transducers 101 and 102 constituting the IC chip 10, and the connector member 5 is liquid-tightly fitted to the joint 1b. As a result, an element chamber SC in a sealed space is formed as shown in FIG. Further, the engaging hole 6 c of the drive lever 6 is engaged and joined to the engaging portion 2 c of the shaft member 2, and the shaft member 2 is configured to be rotationally driven in accordance with the swing of the drive lever 6.

  As shown in FIG. 1, the rotation angle detection device configured as described above is arranged such that the engaging portion 6 b of the drive lever 6 is engaged with the pedal lever PL. At this time, since the drive lever 6 is pressed against the pedal lever PL by the urging force of the return spring 4, the pedal lever PL is held at a preset initial position. When the pedal lever PL is operated from this state, the drive lever 6 swings about the shaft of the shaft member 2 (shaft portion 2b), and the shaft member 2 is rotationally driven against the urging force of the return spring 4. Therefore, the magnet member 20 embedded in the disk portion 2a of the shaft member 2 rotates around the shaft of the shaft portion 2b. In other words, the magnet member 20 supported by the support member 3 (integrated with the housing 1) rotates relative to the IC chip 10 accommodated and supported in the housing 1, and changes permanently according to the change in the rotation angle. A change in the angle of the magnetic field by the magnet 21 is detected by a pair of magnetoelectric transducers (101, 102) in the IC chip 10. Thus, a voltage output corresponding to the magnetic field angle is supplied to the electronic control unit ECU via the connector member 5.

DESCRIPTION OF SYMBOLS 1 Housing 1a Main-body part 1b Joint part 2 Shaft member 3 Support member 4 Return spring 5 Connector member 6 Drive lever 10 IC chip 20 Magnet member SC Element room MC Magnet room 101,102 Magnetoelectric conversion element 110 1st processing circuit 120 2nd Processing circuit 130 comparison circuit 140 output circuit LO output signal line ECU electronic control unit

Claims (6)

  A pair of magnetoelectric conversion elements and a magnet member disposed on a shaft member facing the pair of magnetoelectric conversion elements, and the pair of magnetoelectric conversions according to relative rotation of the magnet member with respect to the pair of magnetoelectric conversion elements A rotation angle signal of the shaft member is detected by an element, and the rotation angle signal is output to an electronic control device; in the rotation angle detection device, a first processing circuit connected to one of the pair of magnetoelectric transducers; A second processing circuit connected to the other of the pair of magnetoelectric transducers, a comparison circuit for comparing the calculation result of the second processing circuit and the calculation result of the first processing circuit, and And a single output circuit for outputting a signal corresponding to the comparison result and the calculation result of the first and second processing circuits, and a single output signal line of the output circuit is electrically connected to the electronic control unit. Rotation angle characterized by being connected Detection device.   2. The rotation angle detection device according to claim 1, wherein the rotation angle detection device is electrically connected to the electronic control unit via an output signal line, a power supply line, and a ground line of the output circuit.   3. The rotation angle detection according to claim 1, wherein the pair of magnetoelectric transducers, the first processing circuit, the second processing circuit, the comparison circuit, and the output circuit are configured by a single IC chip. apparatus.   A housing that houses the pair of magnetoelectric conversion elements; a support member that is joined to the housing and rotatably supports the shaft member; and a connector member that is electrically connected to the pair of magnetoelectric conversion elements, The housing has a main body portion in which an element chamber accommodating at least the pair of magnetoelectric conversion elements is formed, and a joint portion formed integrally with the main body portion and joined to the connector member. The rotation angle detection device according to claim 1, wherein the connector member is fitted and joined in a liquid-tight manner.   The pair of magnetoelectric transducers, the first processing circuit, the second processing circuit, the comparison circuit, and the output circuit are configured by a single IC chip, and the IC chip is accommodated in the element chamber. The rotation angle detection device according to claim 4, wherein   The housing has a magnet chamber formed in the main body portion separately from the element chamber, and is joined to the support member in a state where the magnet member is accommodated in the magnet chamber. The rotation angle detection device according to claim 4 or 5.

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