JP2024159195A - Shifting device - Google Patents

Abstract

An object of the present invention is to prevent an increase in size of a shift body by suppressing erroneous detection of the shift position of the shift body.
[Solution] In a magnetic sensor device 50 of a shift device, a magnetic sensor 56 using a magnetic resistance element outputs output voltages Va, Vb corresponding to the rotation of the magnetic field of a magnet placed on a rotating body. The output voltages Va, Vb have a phase difference of 1/8 of one period, and an angle detection unit 60 detects the rotation angle of the rotating body using the output voltages Va, Vb. In addition, a fault detection unit 62 performs fault detection of the magnetic sensor 56 using the square root of the sum of the squares of the output voltages Va, Vb. In this way, the magnetic sensor device 50 can detect faults in the magnetic sensor 56, suppress erroneous detection of the shift position, and suppress an increase in the size of the shift device.
[Selected Figure] Figure 1

Description

The present invention relates to a shift device that detects the shift position of a shift body.

The shift lever device disclosed in Patent Document 1 has two magnets on either side of the center of rotation of the ball axle, which rotates in conjunction with the operation of the shift lever, and two detection elements using Hall sensors or the like are arranged on a board arranged along a plane passing through the center of rotation of the ball axle. The detection elements are mounted on the top and bottom of the board, one each, and are used to detect the operating position of the shift lever. In the shift lever device, if one detection element fails, the other detection element can be used, ensuring redundancy.

International Publication No. 2018/123277

However, even if two sensors are provided, if it is not possible to determine whether a sensor has failed, redundancy cannot necessarily be ensured, and there is room for improvement.

The present invention was made in consideration of the above-mentioned facts, and aims to provide a shift device that can prevent the shift position of the shift body from being erroneously detected and prevent the shift device from becoming large.

The shift device of the first aspect includes a shift body that is moved by being operated to change the shift position, a rotor that can rotate within half a rotation and is rotated by moving the shift body to a rotation position corresponding to the shift position, a detectable body that is placed on the rotor and rotates integrally with the rotor to rotate the magnetic field, a magnetic field detection unit using a magnetic detection means that is disposed in the magnetic field facing the detectable body using a magnetic resistance element and outputs a first output value and a second output value that change in a sine wave shape that makes one cycle in half a rotation of the rotor and has a phase difference between them that is 1/4 of the one cycle when outputting an output value corresponding to the rotation of the magnetic field, an angle detection unit that detects the rotational position of the rotor corresponding to the shift position of the shift body from the first output value and the second output value, and a fault detection unit that detects whether or not a fault has occurred in the magnetic detection means using the square root value of the sum of the squares of the first output value and the second output value of the magnetic detection means.

In the second aspect of the shift device, in the first aspect, the fault detection unit detects that a fault has occurred in the magnetic detection means when the square root value of the sum of squares falls outside a preset tolerance range.

In the third aspect of the shift device, in the second aspect, the magnetic field detection unit includes a temperature detection means for detecting the ambient temperature of the magnetic detection means, and the tolerance range in the fault detection unit is corrected according to the ambient temperature.

The fourth aspect of the shift device is any one of the first to third aspects, in which the magnetic field detection unit includes two of the magnetic detection means, the angle detection unit detects the rotational position of the rotor based on each of the two magnetic detection means, and the fault detection unit detects whether or not a fault has occurred in each of the two magnetic detection means.

The fifth aspect of the shift device is any one of the first to fourth aspects, and includes an output means that, when a failure of the magnetic detection means is detected, stops outputting an output signal for changing the shift position of the transmission to the shift position of the shift body that corresponds to the rotational position of the rotating body detected using the first output value and the second output value of the magnetic detection means.

In the shift device of the first aspect, the shift body is moved by operating it, and the shift position is changed. When the shift body is moved, the rotating body is rotated within half a turn and is placed at a rotational position that corresponds to the shift position of the shift body. In addition, a detectable body is placed on the rotating body, and the magnetic field is rotated by rotating the detectable body as one unit.

The magnetic field detection unit faces the object to be detected and is disposed within the magnetic field of the object to be detected, and magnetic detection means is disposed in the magnetic field detection unit. The magnetic detection means uses a magnetoresistance element, and when outputting an output value according to the rotation of the magnetic field, it outputs a first output value and a second output value that change in a sine wave shape with one cycle per half rotation of the rotating body, and the phase difference between them is 1/4 of one cycle.

Here, the angle detection unit detects the rotational position of the rotor corresponding to the shift position of the shift body from the first output value and the second output value. Also, the fault detection unit detects whether or not a fault has occurred in the magnetic detection means by using the square root value of the sum of the squares of the first output value and the second output value of the magnetic detection means.

As a result, whether or not a malfunction has occurred in the magnetic detection means is detected using the first output value and the second output value output by the magnetic detection means, so that it is possible to prevent the shift position of the shift body from being erroneously detected by a malfunctioning magnetic detection means. In addition, since it is possible to detect a malfunction in the magnetic detection means itself, the device can be made smaller than when malfunction detection is performed using multiple magnetic detection means.

In the second aspect of the shift device, the fault detection unit has a preset tolerance range for the square root value of the sum of squares, and detects that a fault has occurred in the magnetic detection means when the square root value of the sum of squares falls outside the tolerance range. This makes it possible to prevent a fault from being detected in a magnetic detection means that cannot be said to be faulty.

In the shift device of the third aspect, the magnetic field detection unit includes a temperature detection unit that detects the environmental temperature of the magnetic detection means, and the fault detection unit corrects the allowable range of the square root value of the sum of squares according to the environmental temperature of the magnetic detection means. This makes it possible to suppress erroneous determination of a fault even if the first output value and the second output value of the magnetic detection means change due to a change in the environmental temperature.

In the fourth aspect of the shift device, the magnetic field detection unit includes two magnetic detection means. The angle detection unit detects the rotational position of the rotor for the two magnetic detection means, and the fault detection unit detects whether a fault has occurred for each of the two magnetic detection means. This makes it possible to detect the rotational position of the rotor corresponding to the shift position of the shift body even if a fault is detected in one of the angle detection means.

In the fifth aspect of the shift device, the output means outputs an output signal for changing the shift position of the transmission to the shift position of the shift body corresponding to the rotational position of the rotating body detected using the first output value and the second output value of the magnetic detection means. Furthermore, if a malfunction is detected in the magnetic detection means, the output means stops outputting the output signal based on the first output value and the second output value of the magnetic detection means. This makes it possible to prevent the shift range of the transmission from being changed to an erroneously detected shift position.

1 is a block diagram showing a schematic configuration of a magnetic sensor device according to an embodiment of the present invention. FIG. 2 is a perspective view showing the appearance of the shift device according to the embodiment, as viewed diagonally rear to the right. FIG. 2 is a perspective view showing a main part inside the shift device as seen diagonally rear to the right. FIG. 2 is a perspective view showing a main part of the shift device as viewed diagonally downward from the right. 5A and 5B are diagrams showing an outline of the change in output voltage with respect to the rotation angle. 4 is a diagram showing an outline of the relationship between the output voltage of a magnetic sensor and the rotation angle; 4 is a diagram showing an outline of output voltage and rotation angle set in the magnetic sensor device; FIG. FIG. 13 is a block diagram showing a schematic configuration of a magnetic sensor device according to a modified example. 13 is a diagram showing an outline of output voltage and rotation angle set in a magnetic sensor device according to a modified example. FIG.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.
Fig. 2 shows a perspective view of the shift device 10 according to the embodiment of the present invention as viewed from the right rear, and Fig. 3 shows a perspective view of the interior of the shift device 10 as viewed from the right rear. Fig. 4 shows a perspective view of the main parts of the shift device as viewed from the right lower. In the drawings, the front, left, and top of the shift device 10 are indicated by arrows FR, LH, and UP, respectively.

The shift device 10 is installed in the console (not shown) of a vehicle (automobile), and the front, left, and top of the shift device 10 face toward the front, left, and top of the vehicle, respectively.

As shown in Figures 2 and 3, the shift device 10 is provided with a roughly rectangular box-shaped plate 12 as a support, and the plate 12 is fixed inside the console. The plate 12 is provided with a left plate 12A on the left side and a right plate 12B on the right side, with the left plate 12A and the right plate 12B assembled in the left-right direction. Note that the right plate 12B has been removed in Figure 3.

At the rear end of the plate 12, a biasing surface 16 (moderating surface) is provided as a biased portion constituting the biasing mechanism 14 (moderating mechanism), and the biasing surface 16 is formed concavely on the rear side. The vertical center of the biasing surface 16 is the retaining surface 16A, and the biasing surface 16 is inclined in the forward direction as it moves outward in both the vertical directions from the retaining surface 16A.

A roughly rectangular columnar lever 20 is provided as a shift body at the rear of the plate 12 (in front of the biasing surface 16), and the lever 20 is elongated in the vertical direction. A roughly cylindrical central shaft 20A penetrates and fits into the lower end of the lever 20, and the central shaft 20A is rotatably supported by the left plate 12A and the right plate 12B with its axial direction in the left-right direction. The lever 20 is supported by the plate 12 so that it can rotate (move) in a predetermined range in the front-rear direction around the central shaft 20A.

The upper part of the lever 20 is rotatably inserted through the upper wall (not shown) of the plate 12 and the console, and the upper part of the lever 20 can be rotated by a vehicle occupant (particularly the driver). The lever 20 is of a momentary type, and is disposed in the H position (home position) as a shift position (predetermined shift position). The lever 20 is operated forward (forward, in the direction of arrow A) from the H position to be disposed in the Nr position (neutral position) and R position (reverse position) as shift positions in this order. The lever 20 is also operated rearward (rear, in the direction of arrow B) from the H position to be disposed in the Nd position (neutral position) and D position (drive position) as shift positions in this order.

A generally cylindrical biasing tube 22 with a bottom is integrally provided at the lower end of the lever 20, and the biasing tube 22 protrudes rearward and has an open interior. A generally cylindrical biasing pin 24 (moderation pin) is fitted into the biasing tube 22 as a biasing member constituting the biasing mechanism 14, and the biasing pin 24 is movable in the front-rear direction along the biasing tube 22, and its rear surface (the tip surface on the biasing surface 16 side) protrudes in a spherical shape. A spring (compression coil spring, not shown) is housed inside the biasing tube 22 as a biasing part, and the spring biases the biasing pin 24 rearward. The lever 20 is held (biased) in the H position by the biasing force of the spring, with the rear surface of the biasing pin 24 coming into contact with the holding surface 16A of the biasing surface 16.

When the lever 20 is operated forward and backward from the H position, the rear surface of the biasing pin 24 is moved vertically outward from the holding surface 16A of the biasing surface 16 against the biasing force of the spring. Also, when the lever 20 is operated from the H position and the operating force is released, the rear surface of the biasing pin 24 is moved along the biasing surface 16 to the holding surface 16A by the biasing force of the spring, and the lever 20 is rotated (returned) to the H position.

A first gear 26, which is a substantially rectangular plate-like shape, is integrally provided at the lower end of the lever 20, and protrudes forward and is disposed vertically in the left-right direction. A plurality of first gear teeth 26A are formed at the front end of the first gear 26, and the plurality of first gear teeth 26A are arranged at equal intervals along the circumferential direction within a required angular range around the central axis 20A.

A roughly cylindrical resin rotating body 30 is provided in front of the lever 20 within the plate 12 as a moving body (rotating body). A roughly cylindrical support shaft (not shown) is integrally provided in the middle of the left wall of the plate 12 (the left wall of the left plate 12A) in the front-to-rear direction, and the support shaft extends to the right from the left wall of the plate 12. The support shaft of the plate 12 is coaxially inserted from the left into the rotating body 30, and the rotating body 30 is supported within the plate 12 so as to be rotatable (movable) around the support shaft.

A long rectangular plate-shaped assembly claw 32 is integrally provided on the left wall of the plate 12 (left plate 12A) above and below the support shaft as an assembly part, and the assembly claw 32 extends to the right. The upper and lower assembly claws 32 are disposed above and below the rotating body 30. A trapezoidal column-shaped assembly protrusion 32A is integrally provided on the tip (right end) of each assembly claw 32, and each assembly protrusion 32A protrudes toward the side facing each other (the support shaft side).

A circular plate-shaped assembly plate 30A is disposed integrally with the rotor 30 in the left-right middle portion (axial middle portion) as an assembly receiving portion, and the assembly plate 30A is formed coaxially with the rotor 30. When the support shaft is fitted into the rotor 30, the assembly plate 30A is disposed between the upper and lower assembly claws 32, and the assembly protrusion 32A abuts (surface contacts) against the right side surface of the assembly plate 30A, and the rotor 30 abuts (surface contacts) against the left wall of the plate 12. Therefore, the rotor 30 is rotatably assembled to the plate 12, with the assembly plate 30A's movement to the right being restricted by the assembly protrusion 32A, and its movement to the left being restricted by the left wall of the plate 12, so that the rotor 30 is prevented from moving to the left and right.

The second gear 34 is integrally provided on the left side of the mounting plate 30A of the rotating body 30. The second gear 34 is provided with a plurality of second gear teeth 34A, which are arranged at equal intervals along the circumferential direction within a required angular range around the rotating body 30. The second gear 34 is located on the rear side of the rotating body 30, and the first gear teeth 26A of the first gear 26 of the lever 20 are inserted between the second gear teeth 34A of the second gear 34 (the second gear teeth 34A may be inserted between the first gear teeth 26A).

As a result, the second gear teeth 34A mesh with the first gear teeth 26A to connect the rotor 30 and the lever 20, and the rotor 30 is disposed in the H rotation position (prescribed position) when the lever 20 is in the H position. The rotor 30 is rotated in the direction of arrow C by rotating the lever 20 from the H position to the R position (direction of arrow A) via the Nr position, and is rotated to the R rotation position via the Nr rotation position. The rotor 30 is rotated in the direction of arrow D by rotating the lever 20 from the H position to the D position (direction of arrow A) via the Nd position, and is rotated to the D rotation position via the Nd rotation position. In the shift device 10, the first gear 26 and the second gear 34 are set so that the angle range from the R rotation position to the D rotation position of the rotor 30 is an angle range (within half a rotation of the rotor 30) corresponding to the magnetic sensor device 50 described later.

On the other hand, the rotor 30 has a generally cylindrical regulating tube 36 with a bottom formed coaxially at the right end as a regulating part. The regulating tube 36 has a larger diameter than the left side of the rotor 30, and the inside is open to the right. The peripheral wall of the regulating tube 36 is divided into a front peripheral wall 36A on the front side and at the center in the vertical direction, an upper peripheral wall 36B on the rear side and at the top, and a lower peripheral wall 36C on the rear side and at the bottom.

The right part of the rotating body 30 is integrally provided with mounting claws 38 (one side is shown in FIG. 4) in the shape of a substantially long rectangular plate as a mounting part at the top and bottom, and the mounting claws 38 extend from the left side to the right side from the regulating tube 36. The mounting claws 38 are disposed between the front peripheral wall 36A and the upper peripheral wall 36B of the regulating tube 36, and between the front peripheral wall 36A and the upper peripheral wall 36B of the regulating tube 36, respectively, and the mounting claws 38 are disposed perpendicular to the up-down direction (left-right direction). A trapezoidal columnar mounting protrusion 38A is integrally provided at the tip (right end) of the mounting claw 38, and the mounting protrusion 38A protrudes toward the central axis of the rotating body 30.

In this rotating body 30, a roughly disk-shaped magnet 40 serving as a detected object is placed inside the regulating tube 36. The magnet 40 is roughly disk-shaped, and roughly rectangular column-shaped mounting posts 40A serving as mounting objects are integrally provided on the upper and lower sides of the left end of the magnet 40 (one side is shown in FIG. 4). The mounting posts 40A extend in the front-to-rear direction, and the left surface of the mounting posts 40A is flush with the left surface of the magnet 40. The upper and lower mounting posts 40A are formed point-symmetrically with respect to the central axis of the magnet 40.

The magnet 40 is disposed on the rotor 30 with the mounting post 40A being disposed between the front peripheral wall 36A and the upper peripheral wall 36B of the regulating tube 36, and between the front peripheral wall 36A and the lower peripheral wall 36C, and fitted into the regulating tube 36. As a result, the magnet 40 is surrounded by the front peripheral wall 36A, the upper peripheral wall 36B, and the lower peripheral wall 36C, and thus the radial movement of the magnet 40 is restricted. In addition, the right surface of the magnet 40 abuts (surface contacts) against the mounting protrusion 38A, and the left surface abuts (surface contacts) against the left surface (bottom surface) inside the regulating tube 36, thereby restricting the axial (left-right) movement of the rotor 30. Furthermore, the rear surface of the upper mounting column 40A and the rear surface of the lower mounting column 40A of the magnet 40 are in surface contact with the front end surface of the upper peripheral wall 36B and the front end surface of the lower peripheral wall 36C of the regulating tube 36, respectively, thereby restricting the circumferential movement (rotation) of the rotating body 30.

The magnet 40 is positioned on the rotating body 30 by restricting radial, circumferential and axial movement of the magnet 40 relative to the rotating body 30, and when the rotating body 30 rotates, the direction of the generated magnetic field (magnetic flux direction, magnetic field line direction) rotates integrally with the rotating body 30.

The shift device 10 is provided with a magnetic sensor device 50 for detecting the rotation angle θ of the magnetic field of the magnet 40. FIG. 1 shows a block diagram of the schematic configuration of the magnetic sensor device 50.

The magnetic sensor device 50 detects the shift position of the lever 20 by detecting the rotational position (rotation angle) of the magnetic field of the magnet 40, which is rotated by turning the lever 20. As shown in FIG. 1, the magnetic sensor device 50 is electrically connected to a shift control ECU 48 for controlling the shifting of the vehicle's transmission 46 (automatic transmission), and the magnetic sensor device 50 outputs a shift signal Os to the shift control ECU 48 as an output signal indicating the shift position of the lever 20 determined by the rotation angle of the magnet 40. As a result, the shift position of the transmission 46 in the vehicle is changed according to the shift position of the lever 20.

The magnetic sensor device 50 includes a sensor IC 52 as a magnetic field detection unit, and a detection circuit unit 54. As shown in Figures 3 and 4, the sensor IC 52 is disposed facing the magnet 40 on the right side of the magnet 40 of the rotating body 30 in the left-right direction (axial direction), and the sensor IC 52 is attached to the right plate 12B within the plate 12 (not shown).

The magnet 40 has a north pole on one side in the diameter direction and a south pole on the other side in the diameter direction, and the magnet 40 generates a magnetic field in the space on both sides in the axial direction. The sensor IC 52 is placed close to the magnet 40 and in a region where the strength of the magnetic field generated by the magnet 40 does not change. In other words, the sensor IC 52 is placed so that the magnetic field lines (magnetic flux) generated between the north pole and south pole of the magnet 40 intersect in a region where they are approximately parallel.

As a result, when the rotor 30 rotates and the magnet 40 rotates, the magnetic field of the magnet 40 rotates relative to the sensor IC 52 according to the rotation angle of the rotor 30. When the magnetic field of the magnet 40 rotates relative to the sensor IC 52, the angle of the magnetic field lines that intersect with the sensor IC changes. Note that, below, the direction of the magnetic field lines is defined as the direction of the magnetic field generated by the magnet 40 (magnetic flux direction).

As shown in FIG. 1, the sensor IC 52 contains a sensor chip (not shown) on which a magnetic sensor is formed as a magnetic detection means. The sensor IC 52 of the magnetic sensor device 50 according to this embodiment has two sets of magnetic sensors 56A and 56B formed on the sensor chip as the magnetic sensor 56, and the sensor IC 52 faces the magnet 40 so that the sensor chip is parallel to the magnetic field lines. Note that the magnetic sensors 56A and 56B have the same basic configuration, and the same configuration will be described as the magnetic sensor 56.

The magnetic sensor 56 (56A, 56B) is composed of two sets of magnetic elements 58. The magnetic elements 58 are magnetoresistive elements (MR: Magneto Resistive) whose electrical resistivity (electrical resistance value) changes due to the magnetoresistive effect, and the magnetic sensor 56 is a so-called MR sensor. In this embodiment, an anisotropic magnetoresistive element (AMR: Anisotropic Magneto Resistive) can be used as an example of the magnetoresistive element. In addition, the magnetoresistive element may be a semiconductor magnetoresistive element (SMR: Semiconductor Magneto Resistive) using a semiconductor thin film, or a giant magnetoresistive element (GMR: Giant Magneto Resistive) using a laminated film of a ferromagnetic material, a non-magnetic metal, and a ferromagnetic material.

A magnetoresistance element is formed from a ferromagnetic film (thin film), and the degree of scattering of electrons changes when the magnetization direction (magnetic flux direction) of the ferromagnetic film is parallel to the direction of the current, and when the magnetization direction is perpendicular to the direction of the current, resulting in a change in electrical resistivity (electrical resistance value). For magnetoresistance elements (anisotropic magnetoresistance elements), ferromagnetic materials such as nickel (Ni) and iron (Fe) or alloys containing these ferromagnetic materials as their main components can be used. This allows the formation of an element using the magnetoresistance element, which provides a resistance value according to the direction of magnetization relative to the direction of the current. In the following explanation, the element is considered to be sensitive (highly sensitive) in the direction where the direction of the current and the direction of magnetization overlap.

The magnetic element 58 is formed by bridging elements each formed using a magnetic resistance element. For example, the elements are formed as thin bands of magnetic resistance elements arranged in a predetermined pattern with their longitudinal directions parallel to each other and at predetermined intervals in the width direction, with one longitudinal end of the magnetic resistance element connected to the adjacent magnetic resistance element on the inside of the arrangement direction, and the other longitudinal end of the magnetic resistance element connected to the adjacent magnetic resistance element on the outside of the arrangement direction. This forms the element so that it has sensitivity in one direction.

The magnetic elements are connected in a bridge shape, with four elements formed so that the directions of sensitivity between adjacent elements cross (orthogonal). The magnetic sensor 56 is composed of two magnetic elements 58A and 58B, whose directions of sensitivity are shifted by π/8 between the elements.

As a result, the magnetic sensor 56 outputs a signal that changes like a sine wave, with one period being one half rotation (π) of the magnet 40. Figures 5(A) and 5(B) show diagrams that outline the output voltages of the magnetic elements 58A and 58B of the magnetic sensor 56 versus the rotation angle θ of the magnet 40.

In the following description, the output signal of one of the magnetic elements 58A and 58B is the output voltage Va as the first output value, and the output signal of the other is the output voltage Vb as the second output value. In Figures 5(A) and 5(B), the horizontal axis represents the rotation angle θ of the magnet 40, and the vertical axis represents the voltage (voltage value v).

The magnetic sensor 56 operates when supplied with a voltage VDD, and outputs output voltages Va and Vb, which are set to 0 (v) to VDD (v). The center voltages Vxc and Vyc are the center voltages of the output voltage Va and the output voltage Vb, respectively. The center voltages Vxc and Vyc may be different voltages, but in the magnetic sensor 56, Vxc=Vyc. Also, FIG. 5(B) shows a case where the magnetic sensor 56 (magnetic elements 58A and 58B) are arranged based on the rotation angle θ=0, and FIG. 5(B) shows a case where the magnetic sensor 56 (magnetic elements 58A and 58B) are arranged based on the H rotation position of the magnet 40.

In the following description, the amplitude of the output voltage Va and the amplitude of the output voltage Vb are the same, but the output voltage Va and the output voltage Vb may be different. Furthermore, the voltage x of the output voltage Va indicates the potential difference with the central voltage Vxc at the origin, and the voltage y of the output voltage Vb indicates the potential difference with the central voltage Vyc at the origin.

As shown in FIG. 5B, in the magnetic sensor 56, the direction in which each element is sensitive is shifted by π/8 between the two magnetic elements 58A and 58B, so that when the rotation angle θ is in the range of 0≦θ≦π, there is one cycle of output voltages Va and Vb. Therefore, the output voltage Va changes in a sine waveform with respect to the rotation angle θ, and the output voltage Vb changes in a cosine waveform.

As shown in FIG. 5(A), in the magnetic sensor device 50, a rotation angle θ (for example, a position where the rotation angle θ ≈ 0) corresponding to the H rotation position of the magnet 40 is set within the detectable range of the rotation angle θ. In addition, in the magnetic sensor device 50, an R rotation position, an Nr rotation position, an Nd rotation position, and a D rotation position are set within the magnetic field angle range centered on the H rotation position, and a rotation angle θ corresponding to each rotation position is set (not shown in FIG. 5(A)). In addition, in the magnetic sensor device 50, the range from the R rotation position to the D rotation position is the range of change in the magnetic field angle (magnetic field angle range). The detectable range of the rotation angle θ is set to a range of π.

Meanwhile, the sensor IC 52 is electrically connected to the detection circuit unit 54, and the output voltages Va, Vb of the magnetic sensors 56 (56A, 56B) are input to the detection circuit unit 54. The detection circuit unit 54 detects the rotation angle θ of the magnet 40 from the output voltages Va, Vb of the magnetic sensors 56 to detect the rotation position of the rotor 30 corresponding to the shift position of the lever 20. The detection circuit unit 54 also outputs a shift signal Os indicating the shift position of the lever 20 to the gear shift control ECU 48.

The detection circuit unit 54 can be an IC (integrated circuit) including a microcomputer (not shown). The microcomputer has a CPU, RAM, ROM, and storage as a non-volatile memory connected by a bus, and the CPU reads out a program stored in the ROM and storage, expands it into the RAM, and executes it to realize functions according to the program.

The microcomputer of the detection circuit unit 54 stores an angle detection program, a fault detection program, and a judgment output program in the ROM and storage. This allows the detection circuit unit 54 to realize the functions of an angle detection unit 60, a fault detection unit 62, and a judgment output unit 64. In addition, the detection circuit unit 54 is formed with an angle detection unit 60, a fault detection unit 62, and a judgment output unit 64 corresponding to each of the magnetic sensors 56A and 56B.

The angle detection unit 60 detects the rotation angle θ from the output voltages Va and Vb output from the magnetic sensor 56. The fault detection unit 62 detects a fault in the magnetic sensor 56 from the output voltages Va and Vb output from the magnetic sensor 56 (detects whether or not a fault has occurred).

Figure 6 shows the relationship between the rotation angle θ, the output voltage Va, and the output voltage Vb in a diagram. In Figure 6, the output voltage Va is shown on the horizontal axis and the output voltage Vb on the vertical axis, with the origin being the intersection of the central voltages Vxc and Vyc, and the voltage (voltage value) x of the output voltage Va and the voltage (voltage value) y of the output voltage Vb relative to the origin are shown. Also, in Figure 6, one revolution of the rotation angle θ is π (π/2 to -π/2).

As shown in Fig. 6, if the magnetic sensor 56 is not faulty, the locus of the intersection Q(x, y) of the output voltage Va=x and the output voltage Vb=y when the rotation angle θ is changed will be circular because the amplitudes of the output voltage Va and the output voltage Vb are similar (almost equal). In this case, the radius r and the voltages v and y are ^r2 = ^x2 + ^y2 , so the radius r of the locus is the square root of the sum of the squares of x and y. Note that if the amplitudes of the output voltage Va and the output voltage Vb are different, the locus of the intersection of the voltages x and y will be elliptical.

Here, if the rotation angle θ is replaced with the angle φ, whose period is 2π, then φ=2θ (θ=φ/2), and a relationship defined by a trigonometric function is established between the rotation angle φ (=2θ) and the output voltage Va and output voltage Vb. As a result, for example, the angle φ is tan ^-1 φ=y/x, and the rotation angle θ can be obtained from the output voltages Va and Vb. The angle detection unit 60 detects the rotation angle θ from the output voltages Va and Vb.

Furthermore, if the magnetic sensor 56 has a malfunction or other defect, at least one of the output voltage Va and the output voltage Vb will change (the value will be different from that in the normal state). As a result, the intersection Qs of the output voltage Va (=x) and the output voltage Vb (=y) will be off the circle (locus) of radius r. In other words, even if the rotation angle θ can be detected from the voltage xs of the output voltage Va and the voltage ys of the output voltage Vb, when the circle (reference circle) T of radius r is used as the reference, the value s of the square root of the sum of the squares of the voltages xs and ys will be s ≠ r.

The fault detection unit 62 then pre-sets a reference circle T using a magnetic sensor 56 that is not faulty as a reference. The fault detection unit 62 detects whether the value obtained from the square root of the sum of the squares of the output voltage Va (voltage x) and the output voltage Vb (voltage y) is on the reference circle T (including whether it can be considered to be shaped like the reference circle T) or deviates from the reference circle T, thereby detecting whether or not a fault has occurred in the magnetic sensor 56.

In addition, at least one of the output voltages Va and Vb of the magnetic sensor 56 may change if the magnetic field formed by the magnet 40 is affected by noise (external disturbance) or if the magnetic sensor 56 itself is affected by noise. For this reason, in the magnetic sensor device 50 (fault detection unit 62), an allowable range 66 is set with a predetermined width centered on the reference circle T for fault detection, and the allowable range 66 is stored in the fault detection unit 62 as a map.

When the fault detection unit 62 has not detected a fault in the corresponding magnetic sensor 56, the judgment output unit 64 outputs a shift signal Os indicating the shift position of the lever 20 determined from the rotation angle θ detected by the angle detection unit 60. In addition, when the fault detection unit 62 detects a fault in the magnetic sensor 56, the judgment output unit 64 stops outputting the shift signal Os corresponding to the rotation angle θ detected by the corresponding magnetic sensor 56.

The judgment output unit 64 outputs a shift signal Os based on the detection result of one of the two magnetic sensors 56 (56A, 56B) (for example, magnetic sensor 56A), and if a fault is detected in this magnetic sensor 56, it outputs a shift signal Os based on the rotation angle θ detected by the other magnetic sensor 56 (the magnetic sensor 56 in which no fault is detected).

In the shift device 10 configured in this manner, the biasing pin 24 disposed on the lever 20 in the biasing mechanism 14 is held in contact with and against the retaining surface 16A of the biasing surface 16 in the plate 12 by the biasing force of the spring, thereby holding the lever 20 in the H position. Also, in the shift device 10, by operating the lever 20 forward or backward, the biasing pin 24 is moved upward or downward from the retaining surface 16A along the biasing surface 16 against the biasing force of the spring. This causes the lever 20 to rotate and the shift position to move from the H position to the Nr position and then to the R position via the Nr position, and then to be placed in the Nr position and R position, or from the H position to the Nd position and then to the D position via the Nd position, and then to be placed in the Nd position and D position.

In the shift device 10, the first gear 26 of the lever 20 is meshed with the second gear 34 of the rotating body 30, and the rotating body 30 on which the magnet 40 is disposed is connected to the lever 20. In the shift device 10, the rotating body 30 is rotated by operating the lever 20, and the magnet 40 is rotated. As a result, in the shift device 10, the shift position of the lever 20 is set to the Nr position, R position, Nd position, or D position, and the magnet 40 is disposed in the Nr rotation position, R rotation position, Nd rotation position, or D rotation position.

Meanwhile, the shift device 10 is provided with a magnetic sensor device 50, and in the magnetic sensor device 50, a sensor IC 52 in which a magnetic sensor 56 is formed faces the magnet 40. Therefore, in the magnetic sensor device 50, when the magnet 40 rotates together with the rotor 30 to rotate the direction of the magnetic field, the magnetic sensor 56 detects the rotation angle of the magnetic field and detects whether the rotation position of the rotor 30 is the Nr rotation position, the R rotation position, the Nd rotation position, or the D rotation position.

Figure 7 shows an outline of the output voltages Va, Vb and rotation angle θ of the magnetic sensor 56 set in the magnetic sensor device 50 in a diagram. In Figure 7, the horizontal axis represents the output voltage Va, and the vertical axis represents the output voltage Vb. Also, in Figure 7, one revolution (one period) of the rotation angle θ is set to π, and the entire circumference around the origin is set as the detectable range.

As shown in FIG. 7, the magnetic sensor device 50 is set with rotation angles θh, θnr, θr, θnd, and θd corresponding to the H rotation position, Nr rotation position, R rotation position, Nd rotation position, and D rotation position of the rotating body 30. In addition, in the magnetic sensor device 50, a normal magnetic sensor 56 is used to set a reference circle T, and a range of a predetermined width (width along the radial direction of the reference circle T) centered on the reference circle T is set as an allowable range 66.

The magnetic sensor device 50 uses a magnetic sensor 56. The magnetic sensor 56 is composed of magnetic elements 58A and 58B, and outputs output voltages Va and Vb that are out of phase with each other by π/8. The angle detection unit 60 detects the rotation angle θ of the rotor 30 based on the output voltages Va and Vb of the magnetic sensor 56.

Failure detection unit 62 detects a fault in magnetic sensor 56 that outputs output voltages Va and Vb based on output voltages Va and Vb of magnetic sensor 56. At this time, if intersection point P of output voltage Va and output voltage Vb is within tolerance range 66, fault detection unit 62 detects that there is no fault in magnetic sensor 56 that outputs output voltages Va and Vb.

In contrast, the fault detection unit 62 detects a fault in the magnetic sensor 56 that outputs the output voltages Va and Vb when the intersection point P1 of the output voltages Va and Vb is outside the tolerance range 66 (outside in the radial direction) or when the intersection point P2 is inside in the radial direction. That is, in the magnetic sensor 56, when a fault such as a break or short occurs in at least one of the elements constituting the magnetic elements 58A and 58B, the electrical resistance value changes, and at least one of the output voltages Va and Vb changes. As a result, the value of the square root of the sum of the squares of the voltage x of the output voltage Va and the voltage y of the output voltage Vb falls outside the tolerance range 66. The fault detection unit 62 can detect a fault in the magnetic sensor 56 that outputs the output voltages Va and Vb based on whether the value of the square root of the sum of the squares of the output voltages Va and Vb is within the tolerance range 66.

The judgment output unit 64 outputs a shift signal Os indicating the shift position of the lever 20 corresponding to the rotation angle θ detected from the output voltages Va, Vb of the magnetic sensor 56 in which no fault is detected to the transmission control ECU 48. The transmission control ECU 48 changes the shift range of the transmission according to the shift position of the lever 20. As a result, the transmission is changed to the N range (neutral range), R range (reverse range) or D range (drive range) when the lever 20 is placed in the Nr position, Nd position, R position or N position.

In this way, in the magnetic sensor device 50, the magnetic sensor 56 using a magnetic resistance element uses output voltages Va and Vb that are out of phase with each other by 1/8 of one period, and detects a failure of the magnetic sensor 56 based on whether the value of the square root of the sum of the squares of the voltage x of the output voltage Va and the voltage y of the output voltage Vb is within the tolerance range 66.

When detecting a failure of a magnetic sensor 56 or the like, if two magnetic sensors 56 are used, even if it is possible to detect that at least one of the magnetic sensors 56 has failed, it may not be possible to identify the failed magnetic sensor 56, which may result in the vehicle being unable to run properly.

In addition, by using three or more magnetic sensors 56 and comparing their output signals, it is possible to identify the magnetic sensor 56 that has failed. In this case, however, the arrangement space for the magnetic sensors 56 becomes larger, and the magnet 40 must also be made larger so that the same magnetic field can be formed in each magnetic sensor 56, which results in an increase in the size of the shift device.

In contrast, the magnetic sensor device 10 can use the output voltages Va and Vb of the magnetic sensor 56 to detect whether or not the magnetic sensor 56 is faulty. This prevents the shift device 10 from becoming larger in size in order to detect a fault in the magnetic sensor 56 (enabling the shift device 10 to be made smaller).

In addition, in the magnetic sensor device 50, two magnetic sensors 56 are arranged in the sensor IC 52, so even if a fault is detected in one of them, the magnetic sensor 56 in which no fault is detected can be used, improving redundancy.

In addition, the magnetic sensor device 50 uses the square root of the sum of the squares of the voltage x of the output voltage Va and the voltage y of the output voltage Vb, so it can easily detect a fault in the magnetic sensor 56. Moreover, the magnetic sensor device 50 uses the output voltages Va and Vb for detecting the rotation angle θ to detect a fault in the magnetic sensor 56, so no functionality beyond outputting the output voltages Va and Vb to the magnetic sensor 56 is required.

[Modifications]
Next, a modification of this embodiment will be described.
8 is a block diagram showing a schematic configuration of a magnetic sensor device 70 according to a modified example. Note that the basic configuration of the magnetic sensor device 70 according to the modified example is similar to that of the magnetic sensor device 50, and the same components of the magnetic sensor device 70 as those of the magnetic sensor device 50 are given the same reference numerals as those of the magnetic sensor device 50, and the description thereof is omitted.

As shown in FIG. 8, the magnetic sensor device 70 includes a sensor IC 72 and a detection circuit unit 74. The sensor IC 72 includes a temperature sensor 76 formed on a sensor chip as a temperature detection means, and the sensor IC 72 differs from the sensor IC 52 of the magnetic sensor device 50 in that the temperature sensor 76 is formed. In addition, the detection circuit unit 74 includes a temperature correction unit 78 as a correction unit, and the detection circuit unit 74 differs from the detection circuit unit 54 of the magnetic sensor device 50 in that the detection circuit unit 74 includes the temperature correction unit 78.

The temperature sensor 76 may be a thermistor whose resistance value changes depending on temperature. There may be one temperature sensor 76 for the two magnetic sensors 56A, 56B, but the sensor IC 72 is provided with two temperature sensors 76A, 76B. The temperature sensor 76A is disposed adjacent to the magnetic sensor 56A to detect the environmental temperature of the magnetic sensor 56A, and the temperature sensor 76B is disposed adjacent to the magnetic sensor 56B to detect the environmental temperature of the magnetic sensor 56B.

The detection circuit section 74 is provided with a temperature correction section 78A electrically connected to the temperature sensor 76A, and a temperature correction section 78B electrically connected to the temperature sensor 76B.

Figure 9 shows a schematic diagram of the output voltages Va, Vb and rotation angle θ of the magnetic sensor 56 set in the magnetic sensor device 70. In Figure 9, the horizontal axis represents the output voltage Va, and the vertical axis represents the output voltage Vb. Also in Figure 9, one revolution (one period) of the rotation angle θ is set to π, and the entire circumference around the origin is set to the detectable range.

As shown in FIG. 9, in the magnetic sensor device 70, an allowable range 66 is set, and an allowable range 66A of a predetermined width is set radially inside the allowable range 66, and an allowable range 66B of a predetermined width is set radially outside the allowable range 66. The temperature correction units 78A and 78B store maps corresponding to the allowable ranges 66, 66A, and 66B, respectively.

The temperature correction unit 78 (78A, 78B) selects the allowable range 66, 66A, 66B based on the temperature detected by the temperature sensor 76 (76A, 76B), and the selected allowable range is applied to the fault detection unit 62. At this time, the temperature correction unit 78 selects the allowable range 66 when the temperature detected by the temperature sensor 76 is the standard temperature. The temperature correction unit 78 also selects the allowable range 66A when the temperature detected by the temperature sensor 76 is a predetermined temperature higher than the standard temperature, and selects the allowable range 66B when the temperature detected by the temperature sensor 76 is a predetermined temperature lower than the standard temperature. In other words, the temperature correction unit 78 shifts the allowable range 66 according to the temperature detected by the temperature sensor 76.

The magnetic sensor device 70 configured in this manner can achieve the same effects as the magnetic sensor device 50.

On the other hand, some of the magnetic resistance elements that form the magnetic sensor 56 have resistance values that change depending on the environmental temperature. For this reason, in the magnetic sensor 56, the sensitivity increases as the temperature decreases, and the sensitivity decreases as the temperature decreases.

Here, in the magnetic sensor device 70, when the temperature detected by the temperature sensor 76 becomes high, the temperature correction unit 78 selects the allowable range 66A, applies the selected allowable range 66A, and performs fault detection using the output voltages Va and Vb of the magnetic sensor 56. Therefore, in the magnetic sensor device 70, even if the temperature around the magnetic sensor 56 becomes high and the sensitivity of the magnetic sensor 56 decreases, the magnetic sensor device 70 can accurately detect faults in the magnetic sensor 56.

In the magnetic sensor device 70, when the temperature detected by the temperature sensor 76 drops, the temperature correction unit 78 selects the allowable range 66B, applies the selected allowable range 66B, and performs fault detection using the output voltages Va and Vb of the magnetic sensor 56. Therefore, in the magnetic sensor device 70, even if the temperature around the magnetic sensor 56 drops and the sensitivity of the magnetic sensor 56 increases, the magnetic sensor device 70 can accurately detect faults in the magnetic sensor 56.

In addition, in the magnetic sensor device 70, temperature sensors 76A and 76B are provided for each of the magnetic sensors 56A and 56B, so that the allowable range for temperature changes in the magnetic sensors 56A and 56B can be accurately set, allowing for accurate fault detection for each of the magnetic sensors 56A and 56B.

The present invention is not limited to the present embodiment and the modified examples described above. The present invention is not limited to the shift device 10, but can be applied to any shift device that is operated by a passenger to move and change the shift position, and in which the shift body is moved to rotate a rotating body on which a detection body is provided.

10: shift device, 20: lever (shift body), 30: rotating body, 40: magnet (detected body), 48: gear shift control ECU, 50, 70: magnetic sensor device, 52, 72: sensor IC (magnetic field detection section), 56 (56A, 56B): magnetic sensor (magnetic detection means), 60: angle detection section, 62: fault detection section, 64: judgment output section (output section), 66, 66A, 66B: tolerance range, 76 (76A, 76B): temperature sensor (temperature detection means), 78 (78A, 78B): temperature correction section.

Claims (5)

A shift body that is moved by being operated to change the shift position;
a rotor that is rotatable within a half turn and that is rotated by moving the shift body to a rotational position that corresponds to the shift position;
a detection object that is disposed on the rotating body and rotates together with the rotating body to rotate a magnetic field;
a magnetic field detection unit using a magnetic detection means that uses a magnetic resistance element and is disposed in the magnetic field facing the object to be detected, and that outputs an output value according to the rotation of the magnetic field, and outputs a first output value and a second output value that change in a sinusoidal manner with one cycle per half rotation of the rotating body and have a phase difference between them that is ¼ of one cycle;
an angle detection unit that detects a rotational position of the rotating body corresponding to the shift position of the shift body from the first output value and the second output value;
a fault detection unit that detects whether or not a fault has occurred in the magnetic detection means by using a square root value of the sum of squares of the first output value and the second output value of the magnetic detection means;
A shifting device including: The shift device according to claim 1, wherein the fault detection unit detects that a fault has occurred in the magnetic detection means when the square root value of the sum of squares falls outside a preset tolerance range. the magnetic field detection unit includes a temperature detection means for detecting an environmental temperature of the magnetic detection means,
The shift device according to claim 2 , wherein the tolerance in the failure detection unit is corrected in accordance with the environmental temperature. The magnetic field detection unit includes two of the magnetic detection means,
the angle detection unit detects a rotational position of the rotor based on each of the two magnetic detection means,
The failure detection unit detects whether or not a failure has occurred in each of the two magnetic detection means.
2. The shifting device of claim 1, comprising: The shift device according to claim 1, further comprising: an output means for stopping output of an output signal for changing the shift position of the transmission to the shift position of the shift body corresponding to the rotational position of the rotating body detected using the first output value and the second output value of the magnetic detection means when a failure of the magnetic detection means is detected.