JP6300939B2 - Position detection device - Google Patents

Description

  The present invention relates to a position detection device, and more particularly to a position detection device that detects movement of a detection target using a magnetic field generated by a magnet.

  2. Description of the Related Art In recent years, position detection devices including a detection unit that detects a movement of a detection target using a change associated with the movement of the detection target of a magnetic field received from a magnet (a magnet for detection) have become widespread. Such a position detecting device is used for detecting the position of a moving member such as a reciprocating piston or the like, detecting the depression position of a brake pedal attached to the vehicle so as to be rotatable.

  For such a conventional position detection device, for example, Patent Document 1 is disclosed. As shown in FIG. 7, the stop lamp switch 304 (position detection device) according to Patent Document 1 is provided at a predetermined position of the brake pedal 301 (detection target). The brake pedal 301 is attached to a vehicle body frame 302 so as to be swingable in the front-rear direction about a support shaft 303. The stop lamp switch 304 includes a vehicle body side member 305 fixed to the frame 302 and a pedal side member 306 fixed to the brake pedal 301.

  The vehicle body side member 305 has a case 307, a bias magnet 308 (position correction magnet), and a magnetoresistive element 309 (magnetoelectric conversion element) as magnetic detection means. The case 307 includes a fixing portion 307 a that is fixed to the frame 302, and an extending portion 307 b that extends from the fixing portion 307 a toward the pedal side member 306. The bias magnet 308 and the magnetoresistive element 309 are provided at the distal end portion of the extending portion 307b so as to be separated in the vertical direction.

  The pedal side member 306 includes a mounting plate 311, a holding member 312, and a counter magnet 314 (detection magnet). The mounting plate 311 is fixed to the brake pedal 301 so as to face the extended portion 307b of the vehicle body side member 305. The holding member 312 is fixed to the center of a mounting surface 311 a that is a plane of the mounting plate 311 on the vehicle body side member 305 side, and a magnet holding portion 313 is provided inside the holding member 312. The counter magnet 314 is accommodated in the magnet holding part 313.

  The front end surface of the case 307 of the vehicle body side member 305 and the front end surface of the holding member 312 of the pedal side member 306 are disposed so as to contact each other in a non-operation state. When the driver depresses the brake pedal 301, the pedal side member 306 is displaced forward together with the brake pedal 301, and is separated from the vehicle body side member 305 in accordance with the depression amount. As a result, the position of the pedal side member 306 with respect to the vehicle body side member 305 changes, and accordingly, the strength of the magnetic field (magnetic field) applied from the counter magnet 314 to the magnetoresistive element 309 changes. When the stepping by the driver is released, the pedal side member 306 returns to the non-operating state.

  The stop lamp switch 304 detects the depression operation of the brake pedal 301 based on the change in the magnetic field strength accompanying the change in the position of the pedal side member 306 with respect to the vehicle body side member 305.

  In the stop lamp switch 304, the tip surface of the case 307 and the tip surface of the holding member 312 are brought into contact with each other, and the counter magnet 314 and the bias magnet 308 are in a certain positional relationship using the magnetic force of the bias magnet 308. As described above, the position of the counter magnet 314 can be corrected. In the stop lamp switch 304, the positional relationship between the counter magnet 314 and the magnetoresistive element 309 is stabilized in this way, and the detection accuracy is reduced due to variations in the mounting positions of the vehicle body side member 305 and the pedal side member 306. Is suppressed.

JP 2009-192377 A

  However, in the stop lamp switch 304 (position detection device) according to Patent Document 1, the position of the counter magnet 314 is corrected using the magnetic force of the bias magnet 308, so that the front end surface of the case 307, which is a member on the detection unit side, It has been necessary to contact the front end surface of the holding member 312 which is a member on the detection target side. When the member on the detection unit side and the member on the detection target side are brought into contact with each other, when a vibration or impact is applied to the member on the detection unit side or the member on the detection target side with a strong force, the member on the detection unit side And a member on the detection target side collide, and accordingly, a collision sound may be generated, or a member on the detection unit side or a member on the detection target side may be damaged.

  The present invention has been made in view of the actual situation of the prior art, and its purpose is to detect a variation caused by a variation in the mounting position without causing the detection side member and the detection target side member to contact each other. An object of the present invention is to provide a position detection device capable of suppressing a decrease in accuracy.

In order to solve this problem, a position detection device according to the present invention , first , in a position detection device including a detection unit that detects a movement of a detection target using a change associated with the movement of the detection target of a magnetic field received from a magnet, The detection unit includes two magnetoelectric conversion elements, and the two magnetoelectric conversion elements are arranged apart by a distance corresponding to a movement amount due to a predetermined movement of the detection target.

  In the position detection device of this configuration, the distance between the two magnetoelectric transducers is made to correspond to the amount of movement of the detection target due to the predetermined movement, whereby the magnet at the initial position of the detection target (hereinafter abbreviated as the magnet at the initial position). To the strength of the magnetic field received by one of the two magnetoelectric conversion elements (hereinafter, abbreviated as one of the magnetoelectric conversion elements) and the magnet at the position after the movement of the detection target (hereinafter, the magnet at the position after the movement). The magnetic field strength received by the other magnetoelectric conversion element (hereinafter, abbreviated as the other magnetoelectric conversion element) of the two magnetoelectric conversion elements can be made equal. Therefore, by comparing the strength of the magnetic field received by the other magnetoelectric conversion element from the magnet with the strength of the magnetic field received by the one magnetoelectric conversion element from the magnet at the initial position, the detection accuracy for the amount of movement of the detection target can be increased. it can.

  Moreover, in the position detection device of this configuration, the distance between the two magnetoelectric conversion elements is made to correspond to the amount of movement of the detection target, so the positional relationship between the magnet and the detection unit due to variations in the attachment position of the magnet and the detection unit Even when the value changes, the detection accuracy with respect to the amount of movement of the detection target is easily maintained. As a result, it is possible to suppress a decrease in detection accuracy due to variations in attachment positions.

The position detection device according to claim 1 further includes a distance from the magnet at the initial position of the detection target to one of the two magnetoelectric conversion elements in the basic configuration, and after the movement of the detection target. The two magnetoelectric conversion elements are arranged so that a distance from a magnet at a position to the other of the two magnetoelectric conversion elements is equal.

  In the position detection device of this configuration, the distance from the magnet at the initial position to the one magnetoelectric conversion element is made equal to the distance from the magnet at the moved position to the other magnetoelectric conversion element, so that The strength of the magnetic field received by one magnetoelectric conversion element and the strength of the magnetic field received by the other magnetoelectric conversion element from the magnet at the moved position can be made substantially equal. As a result, the detection accuracy with respect to the amount of movement of the detection target can be further increased.

According to a second aspect of the present invention, there is provided the position detecting device according to the second aspect, wherein the two magnetoelectric transducers are further moved from the magnet at the initial position of the detection target to the direction of the central axis of the magnetic field generated by the magnet at the initial position of the detection target. The two magnetoelectric conversions from the magnet at the position after the movement of the detection target with respect to the deviation angle in the direction toward one of the magnetoelectric conversion elements and the direction of the central axis of the magnetic field generated by the magnet at the position after the movement of the detection target The two magnetoelectric conversion elements are arranged so that a deviation angle in a direction toward the other magnetoelectric conversion element of the elements becomes equal.

  In the position detection device having this configuration, the magnet at the initial position is directed to one magnetoelectric conversion element with respect to the direction of the central axis of the magnetic field generated by the magnet at the initial position (hereinafter referred to as the direction of the central axis of the magnetic field at the initial position). Of the direction (hereinafter referred to as the arrangement direction of one magnetoelectric transducer) and the direction of the central axis of the magnetic field generated by the magnet at the position after movement (hereinafter referred to as the direction of the central axis of the magnetic field at the position after movement). To the other magnetoelectric conversion element from the magnet at the moved position (hereinafter referred to as the arrangement direction of the other magnetoelectric conversion element) to be equal to one from the magnet at the initial position. The strength of the magnetic field received by the magnetoelectric conversion element and the strength of the magnetic field received by the other magnetoelectric conversion element from the magnet at the moved position can be made substantially equal. As a result, the detection accuracy with respect to the amount of movement of the detection target can be further increased.

According to a third aspect of the present invention, in the above-described basic configuration, the predetermined movement of the detection target is a movement that rotates together with the magnet by a predetermined angle around the rotation axis, and at the initial position of the detection target. The two magnetoelectrics are along a direction that is shifted from the direction of the central axis of the magnetic field generated by the magnet toward the central axis of the magnetic field generated by the magnet at the position after the movement of the detection target by a half of a predetermined angle. A conversion element is arranged.

  In the position detection device having this configuration, two magnetoelectric conversions are performed along a direction that is shifted from the direction of the central axis of the magnetic field at the initial position by a half of a predetermined angle toward the central axis of the magnetic field at the position after movement. By arranging the elements, the strength of the magnetic field received by one magnetoelectric conversion element from the magnet at the initial position and the strength of the magnetic field received by the other magnetoelectric conversion element from the magnet at the moved position can be made substantially equal. it can. As a result, when the predetermined movement of the detection target is a movement that rotates about a rotation axis by a predetermined angle, the detection accuracy with respect to the movement amount of the detection target can be further increased.

According to a fourth aspect of the present invention, there is provided the position detecting device according to the first aspect, wherein one of the two magnetoelectric conversion elements is in the direction of the central axis of the magnetic field generated by the magnet at the initial position to be detected. The inclination angle of the magnetosensitive direction, and the inclination angle of the other magnetoelectric conversion element of the two magnetoelectric conversion elements with respect to the direction of the central axis of the magnetic field generated by the magnet at the position after the movement of the detection target The magnetosensitive directions of the two magnetoelectric transducers are set so that they are equal.

  In the position detection device of this configuration, the inclination angle of the magnetosensitive conversion direction of one magnetoelectric conversion element with respect to the direction of the central axis of the magnetic field at the initial position and the other magnetoelectric conversion element with respect to the direction of the central axis of the magnetic field at the position after movement. By equalizing the inclination angle in the magnetosensitive direction, the strength of the magnetic field received by one magnetoelectric conversion element from the magnet at the initial position and the strength of the magnetic field received by the other magnetoelectric conversion element from the magnet at the moved position are approximately equal. It can be an equal value. As a result, the detection accuracy with respect to the amount of movement of the detection target can be further increased.

According to a fifth aspect of the present invention, in the above-described basic configuration, the predetermined movement of the detection target is a movement that rotates together with the magnet by a predetermined angle around the rotation axis, and at the initial position of the detection target. Said 2 so as to coincide with the direction shifted from the direction of the central axis of the magnetic field generated by the magnet toward the central axis of the magnetic field generated by the magnet at the position after the movement of the detection object by a half of a predetermined angle. The magnetosensitive direction of two magnetoelectric transducers is set.

  In the position detection device of this configuration, two directions are aligned so as to coincide with the direction shifted by half the predetermined angle from the direction of the central axis of the magnetic field at the initial position toward the central axis of the magnetic field at the position after movement. By setting the magnetosensitive direction of the magnetoelectric conversion element, the strength of the magnetic field received by one magnetoelectric conversion element from the magnet at the initial position and the strength of the magnetic field received by the other magnetoelectric conversion element from the magnet at the moved position are approximately It can be an equal value. As a result, when the predetermined movement of the detection target is a movement that rotates about a rotation axis by a predetermined angle, the detection accuracy with respect to the movement amount of the detection target can be further increased.

  ADVANTAGE OF THE INVENTION According to this invention, the position detection apparatus which can suppress the fall of the detection accuracy resulting from the dispersion | variation in an attachment position can be provided.

It is explanatory drawing which shows the structure of the position detection apparatus which concerns on 1st Embodiment of this invention. It is explanatory drawing which shows the positional relationship of the magnet which concerns on 1st Embodiment of this invention, and a magnetoelectric conversion element. It is explanatory drawing which shows the relationship between the moving distance of the detection target which concerns on 1st Embodiment of this invention, and the strength of the magnetic field which a magnetoelectric conversion element receives. It is a flowchart which shows the detection procedure of the movement which concerns on 1st Embodiment of this invention. It is explanatory drawing which shows the structure of the position detection apparatus which concerns on 2nd Embodiment of this invention. It is explanatory drawing which shows the positional relationship of the magnet and magnetoelectric conversion element which concern on 2nd Embodiment of this invention. It is explanatory drawing which shows the structure of the conventional position detection apparatus.

[First Embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. The directions in each figure are described with X1 as the left direction, X2 as the right direction, Y1 as the forward direction, Y2 as the backward direction, Z1 as the upward direction, and Z2 as the downward direction.

  First, the configuration of the position detection apparatus 1 according to the first embodiment of the present invention will be described with reference to FIG. FIG. 1 is an explanatory diagram showing the configuration of the position detection device according to the first embodiment of the present invention.

  The position detection device 1 according to the first embodiment of the present invention includes a detection unit 10 as shown in FIG. The detection unit 10 is disposed behind the detection target 40 with a predetermined interval, and is fixed to a holding member (not shown).

  The detection unit 10 includes two magnetoelectric conversion elements 20 and a detection circuit 30. The two magnetoelectric conversion elements 20 are a first magnetoelectric conversion element 21 and a second magnetoelectric conversion element 22. The magnetoelectric conversion element 20 changes electrical characteristics such as a resistance value in accordance with the strength of the received magnetic field. As the magnetoelectric conversion element 20, a magnetoresistive element or the like in which a magnetosensitive surface for detecting a magnetic field is formed on one plate surface of a substrate made of a material such as silicon is used. The characteristics of the two magnetoelectric conversion elements are set to be substantially the same.

  In such a magnetoelectric conversion element 20, a magnetic sensitive direction is set. The magnetosensitive direction is the direction of the magnetic field that maximizes the sensitivity of the magnetoelectric transducer 20. In the present embodiment, when the sensitivity of the magnetoelectric conversion element 20 is maximized with respect to the magnetic field from the front, it is assumed that the magnetosensitive direction is facing forward, and the sensitivity of the magnetoelectric conversion element 20 is with respect to the magnetic field from the rear. It is assumed that the magnetosensitive direction faces backward when the maximum value is. For example, when the direction of the magnetic field is rearward and the magnetic sensing direction is frontward, it is assumed that the magnetic field direction and the magnetic sensing direction coincide with each other.

  The detection circuit 30 is a circuit having an arithmetic function, a storage function, and a determination function. The detection circuit 30 is connected to each of the two magnetoelectric conversion elements 20. Then, the detection circuit 30 calculates the strength of the magnetic field received by each magnetoelectric conversion element 20 based on the electrical characteristics of the magnetoelectric conversion element 20, stores the calculated magnetic field strength as a reference value, Judgment is made by comparing the calculated magnetic field strength with a reference value.

  The detection target 40 is a moving member such as a piston that is held by the holding member described above so as to be linearly movable in the front-rear direction. A magnet 50 (detection magnet) magnetized so as to generate a magnetic field toward the detection unit 10 is disposed at a position corresponding to the detection unit 10 of the detection target 40. In the position detection device 1, the relative distance between the detection unit 10 and the magnet 50 changes as the detection target 40 moves, and the change in the magnetic field received by the detection unit 10 at that time is used to detect the detection target. 40 predetermined movements are detected.

  Next, the moving direction of the detection target 40 and the positional relationship between the magnetoelectric transducer 20 and the magnet 50 will be described with reference to FIG. FIG. 2 is an explanatory diagram showing the positional relationship between the magnet and the magnetoelectric transducer according to the first embodiment of the present invention. 2A shows the positional relationship between the magnet 50 and the magnetoelectric conversion element 20 at the initial position, and FIG. 2B shows the positional relationship between the magnet 50 and the magnetoelectric conversion element 20 at the moved position. Yes.

  Hereinafter, the center position of the magnet 50 at the initial position is defined as the initial position Pm1 of the magnet 50, and the state after the detection target 40 has moved by a predetermined distance from the initial position Pm1 is defined as after movement. The position is a position Pm2 after the magnet 50 is moved. Then, the description will be given with the distance between the initial position Pm1 of the magnet 50 and the position Pm2 after the movement of the magnet 50 as the moving distance d of the magnet 50 accompanying the predetermined movement of the detection target 40. The direction at the center position of the magnetic field from the north pole to the south pole of the magnet 50 is the direction of the central axis of the magnetic field generated by the magnet 50. The direction of the central axis of the magnetic field generated by the magnet 50 at the initial position is set as the central axis direction Dm1 of the magnetic field at the initial position, and the direction of the central axis of the magnetic field generated by the magnet 50 at the moved position is The description will proceed with the center axis direction Dm2 of the magnetic field at the position.

  In addition, the magnetosensitive surface of the first magnetoelectric conversion element 21 is defined as a magnetosensitive surface 21a, and the center position of the magnetosensitive surface 21a is defined as a position Ps1 of the first magnetoelectric conversion element 21. In addition, the magnetosensitive surface of the second magnetoelectric conversion element 22 is defined as a magnetosensitive surface 22a, and the center position of the magnetosensitive surface 22a is defined as a position Ps2 of the second magnetoelectric conversion element 22. The description will be made with the distance between the position Ps1 of the first magnetoelectric conversion element 21 and the position Ps2 of the second magnetoelectric conversion element 22 as the distance between the two magnetoelectric conversion elements 20. Further, the description will proceed with the magnetic sensing direction of the first magnetoelectric conversion element 21 as the magnetic sensing direction Ds1, and the magnetic sensing direction of the second magnetoelectric conversion element 22 as the magnetic sensing direction Ds2.

  The direction from the initial position Pm1 of the magnet 50 toward the position Ps1 of the first magnetoelectric conversion element 21 is the arrangement direction of the first magnetoelectric conversion element 21, and the position of the second magnetoelectric conversion element 22 from the position Pm2 after the movement of the magnet 50 is set. The description proceeds with the direction toward the position Ps2 as the arrangement direction of the second magnetoelectric transducer 22. Further, the distance from the initial position Pm1 of the magnet 50 to the position Ps1 of the first magnetoelectric conversion element 21 is the distance L1 from the magnet 50 to the first magnetoelectric conversion element 21 at the initial position, and from the position Pm2 after the movement of the magnet 50 The description will be made with the distance from the magnet 50 to the second magnetoelectric conversion element 22 at the moved position as the distance L2 from the second magnetoelectric conversion element 22 to the position Ps2.

  In the present embodiment, as shown in FIG. 2, the predetermined movement of the detection target 40 detected by the position detection device 1 is predetermined in the direction in which the detection target 40 moves away from the detection unit 10 forward, that is, with respect to the initial position. This is a movement that moves linearly with the magnet 50 by a distance d. The magnet 50 is magnetized so that the central axis direction Dm1 of the magnetic field at the initial position and the central axis direction Dm2 of the magnetic field at the moved position are both directed backward, that is, toward the detection unit 10. .

  The first magnetoelectric conversion element 21 and the second magnetoelectric conversion element 22 are imaginary lines extending backward through the initial position Pm1 of the magnet 50 and the position Pm2 after the movement of the magnet 50, that is, along the moving direction of the magnet 50. Thus, the first magnetoelectric conversion element 21 is positioned rearward and the second magnetoelectric conversion element 22 is positioned frontward so as to be arranged side by side with a predetermined interval. The distance between the two magnetoelectric transducers 20 is set to be the same distance as the moving distance d of the magnet 50 accompanying the predetermined movement of the detection target 40. Therefore, the distance L1 from the magnet 50 to the first magnetoelectric conversion element 21 at the initial position is equal to the distance L2 from the magnet 50 to the second magnetoelectric conversion element 22 at the moved position.

  Further, the magnetic sensing direction Ds1 of the first magnetoelectric transducer 21 and the magnetic sensitive direction Ds2 of the second magnetoelectric transducer 22 are both forward, that is, the central axis direction Dm1 of the magnetic field at the initial position and the magnetic field at the moved position. It is set so as to face the direction that coincides with the central axis direction Dm2.

  Next, the principle of detection of the movement of the detection target 40 according to the present embodiment will be described with reference to FIG. FIG. 3 is an explanatory diagram showing the relationship between the moving distance of the detection target and the strength of the magnetic field received by the magnetoelectric transducer according to the first embodiment of the present invention. In FIG. 3, the horizontal axis represents the moving distance of the magnet 50 accompanying the movement of the detection target 40, and the vertical axis represents the strength of the magnetic field that the magnetoelectric conversion element 20 receives from the magnet 50. A curve A1 (two-dot chain line) indicates the strength of the magnetic field received by the first magnetoelectric conversion element 21 from the magnet 50, and a curve A2 (solid line) indicates the strength of the magnetic field received by the second magnetoelectric conversion element 22 from the magnet 50. It shows. The magnetic field strength H1 is the strength of the magnetic field received by the first magnetoelectric conversion element 21 from the magnet 50 at the initial position, and the magnetic field strength H2 is the magnetic field strength H2 from the magnet 50 at the initial position to the second magnetoelectric conversion element 22. The strength of the magnetic field received.

  As shown in FIG. 3, the strength of the magnetic field received by the second magnetoelectric conversion element 22 from the magnet 50 is H2 at the initial position, and gradually decreases as the distance between the magnet 50 and the second magnetoelectric conversion element 22 increases. Go. Then, based on the strength of the magnetic field received by the second magnetoelectric conversion element 22 from the magnet 50, the distance from the magnet 50 to the second magnetoelectric conversion element 22 is detected, thereby detecting the amount of movement of the detection target 40. Can do.

  Further, as described above, the distance between the two magnetoelectric transducers 20 is set to be the same as the moving distance d of the magnet 50. As a result, the strength of the magnetic field received by the second magnetoelectric conversion element 22 from the magnet 50 at the moved position is substantially equal to the strength H1 of the magnetic field received by the first magnetoelectric conversion element 21 from the magnet 50 at the initial position. .

  In the present embodiment, using the relationship between the strength of the magnetic field received by the first magnetoelectric conversion element 21 from the magnet 50 at the initial position and the strength of the magnetic field received by the second magnetoelectric conversion element 22 from the magnet 50, The strength of the magnetic field received by the first magnetoelectric conversion element 21 from the magnet 50 at the initial position is set as a reference value, and the strength of the magnetic field received by the second magnetoelectric conversion element 22 from the magnet 50 is compared with the reference value, thereby detecting the object 40 to be detected. The detection accuracy for the amount of movement is increased.

  In addition, since the distance between the two magnetoelectric conversion elements 20 is set to be the same as the moving distance d of the magnet 50, the position of the magnet 50 and the detection unit 10 due to variations in the mounting position of the magnet 50 and the detection unit 10 Even when the relationship changes, the detection accuracy for the movement of the detection target 40 is maintained.

  Next, a procedure for detecting the movement of the detection target 40 according to the present embodiment will be described with reference to FIG. FIG. 4 is a flowchart showing a movement detection procedure according to the first embodiment of the present invention.

  As shown in FIG. 4, first, in step S1, the detection unit 10 detects the strength of the magnetic field received by the first magnetoelectric transducer 21 from the magnet 50 at the initial position. In step S2, the detection unit 10 stores the detected magnetic field strength as a reference value. In step S <b> 3, the detection unit 10 starts detecting the movement of the detection target 40.

  Next, in step S <b> 4, the detection unit 10 detects the strength of the magnetic field received by the second magnetoelectric conversion element 22 from the magnet 50. In step S5, the detection unit 10 compares the detected magnetic field strength with a reference value. In step S6, the detection unit 10 makes a determination based on the comparison result. If the detected magnetic field strength is greater than the reference value in step S6, the process returns to step S4. And the procedure after step S4 is repeated. In step S6, if the detected magnetic field strength is below the reference value, the process moves to step S7.

  Next, in step S7, the detection circuit 30 determines that the detection target 40 has made a predetermined movement. Along with this, for example, a predetermined operation such as switching the connection of the external circuit connected to the detection circuit 30 is executed. For example, the position detection device 1 detects the movement of the detection target 40 according to such a procedure. In addition, after the predetermined operation is executed in step 7, the detection unit 10 continues to detect the movement, and when the detected magnetic field strength becomes larger than the reference value again, the executed operation is canceled. It doesn't matter.

  Next, the effect of this embodiment will be described. In the position detection device 1 of the present embodiment, the predetermined movement of the detection target 40 is a movement in which the detection target 40 moves linearly forward by a predetermined distance together with the magnet 50, and the first magnetoelectric conversion element 21 and the second magnetoelectric conversion. The element 22 is disposed along the moving direction of the magnet 50 by the same distance as the moving distance d of the magnet 50. In this way, by making the distance between the two magnetoelectric conversion elements 20 correspond to the movement distance d (movement amount) of the magnet 50 due to the predetermined movement of the detection target 40, the first magnetoelectric conversion element from the magnet 50 at the initial position. The strength of the magnetic field received by 21 and the strength of the magnetic field received by the second magnetoelectric conversion element 22 from the magnet 50 at the moved position can be made equal. Therefore, the detection of the moving distance of the detection target 40 is performed by comparing the strength of the magnetic field received by the second magnetoelectric conversion element 22 from the magnet 50 with the strength of the magnetic field received by the first magnetoelectric conversion element 21 from the magnet 50 at the initial position. Accuracy can be increased.

  In addition, in the position detection device 1 of the present embodiment, the distance between the two magnetoelectric conversion elements 20 is made to correspond to the movement distance of the detection target 40, so that the magnet 50 or the detection unit 10 may vary depending on the mounting position of the magnet. Even when the positional relationship between the detection unit 50 and the detection unit 10 changes, the detection accuracy with respect to the movement distance of the detection target 40 is easily maintained. As a result, it is possible to suppress a decrease in detection accuracy due to variations in attachment positions.

  In the position detection device 1 of the present embodiment, the distance L1 from the magnet 50 to the first magnetoelectric conversion element 21 at the initial position and the distance L2 from the magnet 50 to the second magnetoelectric conversion element 22 at the moved position are obtained. By making them equal, the strength of the magnetic field received by the first magnetoelectric conversion element 21 from the magnet 50 at the initial position and the strength of the magnetic field received by the second magnetoelectric conversion element 22 from the magnet 50 at the moved position are substantially equal. be able to. As a result, the detection accuracy with respect to the movement distance of the detection target 40 can be further increased.

[Second Embodiment]
Hereinafter, a second embodiment of the present invention will be described with reference to the drawings. In addition, in this embodiment, when it is the same structure as 1st Embodiment mentioned above, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted.

  First, the configuration of the position detection apparatus 101 according to the second embodiment of the present invention will be described with reference to FIGS. FIG. 5 is an explanatory diagram showing the configuration of the position detection apparatus according to the second embodiment of the present invention.

  The position detection apparatus 101 according to the second embodiment of the present invention includes a detection unit 10 as shown in FIG. The detection unit 10 includes two magnetoelectric conversion elements 20 and a detection circuit 30. Thus, the position detection device 101 has the same configuration as the position detection device 1 according to the first embodiment. However, in the present embodiment, the detection target 140 is held so as to be rotatable in the front-rear direction around the rotation axis Po set on the upper side of the detection target 140. As such a detection target 140, for example, a brake pedal or the like that is rotatably attached to the vehicle is assumed.

  Next, the moving direction of the detection target 140 and the positional relationship between the magnetoelectric transducer 20 and the magnet 50 will be described with reference to FIG. FIG. 6 is an explanatory diagram showing the positional relationship between the magnet and the magnetoelectric transducer according to the second embodiment of the present invention. 6A shows the positional relationship between the magnet 50 and the magnetoelectric conversion element 20 at the initial position, and FIG. 6B shows the positional relationship between the magnet 50 and the magnetoelectric conversion element 20 at the moved position. Yes.

  In the present embodiment, the predetermined movement of the detection target 140 detected by the position detection device 101 is forward by a predetermined angle θ from the initial position around the rotation axis Po, that is, as shown in FIG. It is the movement which rotates with the magnet 50 in the direction away from. The initial position Pm1 of the magnet 50 is a position rotated backward from an angle half the predetermined angle θ (hereinafter simply referred to as an angle θ / 2) from directly below the rotation axis Po. As a result, the position Pm2 after the movement of the magnet 50 is a position rotated forward by an angle θ / 2 from directly below the rotation axis Po.

  In the present embodiment, the magnet 50 is attached so that the direction of the central axis of the magnetic field generated by the magnet 50 faces rearward when the detection target 140 is rotated forward from the initial position by an angle θ / 2. Yes. Therefore, the central axis direction Dm1 of the magnetic field at the initial position is a direction inclined upward by an angle θ / 2 with respect to the rear, and the central axis direction Dm2 of the magnetic field at the position after movement is an angle θ / 2 with respect to the rear. Only the direction tilted downward. Then, the central axis direction Dm1 of the magnetic field at the initial position and the central axis direction Dm2 of the magnetic field at the moved position are different from each other by an angle θ.

  The first magnetoelectric conversion element 21 and the second magnetoelectric conversion element 22 are an imaginary line extending backward through the initial position Pm1 and the moved position Pm2 of the magnet 50, that is, the central axis of the magnetic field at the initial position. The first magnetoelectric conversion element 21 is located rearward and the second magnetoelectric conversion element 22 is located forward along a direction shifted by an angle θ / 2 from the direction Dm1 toward the central axis of the magnetic field at the moved position. As shown in the figure, they are arranged side by side at a predetermined interval. The distance between the two magnetoelectric transducers 20 is set to be the same distance as the moving distance d of the magnet 50 accompanying the predetermined movement of the detection target 140. Further, the magnetosensitive direction Ds1 of the first magnetoelectric transducer 21 and the magnetosensitive direction Ds2 of the second magnetoelectric transducer 22 are the front, that is, the central axis direction Dm1 of the magnetic field at the initial position, and the magnetic field at the position after movement. It is set in a direction that coincides with a direction shifted by an angle θ / 2 toward the central axis.

  When the two magnetoelectric conversion elements 20 are arranged in this way, the distance from the magnet 50 to the first magnetoelectric conversion element 21 at the initial position, and the distance from the magnet 50 to the second magnetoelectric conversion element 22 at the moved position Is the same distance as in the first embodiment. Further, the deviation angle of the arrangement direction of the first magnetoelectric conversion element 21 with respect to the central axis direction Dm1 of the magnetic field at the initial position and the deviation angle of the arrangement direction of the second magnetoelectric conversion element 22 with respect to the central axis direction Dm2 of the magnetic field at the position after movement. Are both equal to an angle θ / 2. In addition, the tilt angle of the magnetosensitive direction Ds1 of the first magnetoelectric conversion element 21 with respect to the central axis direction Dm1 of the magnetic field at the initial position, and the magnetosensitive direction of the second magnetoelectric conversion element 22 with respect to the central axis direction Dm2 of the magnetic field at the moved position. Both the inclination angles of Ds2 are equal to the angle θ / 2.

  Next, the effect of this embodiment will be described. In the present embodiment, the predetermined movement of the detection target 140 is a movement that rotates by a predetermined angle θ about the rotation axis Po. Thus, even if the movement of the detection target 140 is a movement other than the linear movement, the distance between the two magnetoelectric transducers 20 is the movement distance d of the magnet 50 corresponding to the predetermined movement angle θ of the detection target 140. The magnetic field strength received by the first magnetoelectric conversion element 21 from the magnet 50 at the initial position is equal to the magnetic field strength received by the second magnetoelectric conversion element 22 from the magnet 50 at the moved position. Strength. Then, by comparing the strength of the magnetic field received by the second magnetoelectric conversion element 22 from the magnet 50 with the strength of the magnetic field received by the first magnetoelectric conversion element 21 from the magnet 50 at the initial position, as in the first embodiment, The detection accuracy with respect to the moving distance of the detection target 140 can be increased.

  However, when the predetermined movement of the detection target 140 is such a movement, the central axis direction Dm1 of the magnetic field at the initial position and the central axis direction Dm2 of the magnetic field at the position after the movement are different from each other. Therefore, for example, if the two magnetoelectric conversion elements 20 are arranged along the central axis direction Dm1 of the magnetic field at the initial position, or arranged along the central axis direction Dm2 of the magnetic field at the position after movement, There is a deviation between the strength of the magnetic field received by the first magnetoelectric conversion element 21 from the magnet 50 at the position and the strength of the magnetic field received by the second magnetoelectric conversion element 22 from the magnet 50 at the moved position. .

  On the other hand, in the position detection device 101 of the present embodiment, the first position is changed along the direction shifted from the central axis direction Dm1 of the magnetic field at the initial position by the angle θ / 2 toward the central axis side of the magnetic field at the moved position. By disposing the 1 magnetoelectric conversion element 21 and the second magnetoelectric conversion element 22, the deviation angle of the arrangement direction of the first magnetoelectric conversion element 21 with respect to the central axis direction Dm1 of the magnetic field at the initial position, and the magnetic field at the position after the movement The deviation angle of the arrangement direction of the second magnetoelectric conversion element 22 with respect to the central axis direction Dm2 can be made equal.

  Then, a deviation angle of the arrangement direction of the first magnetoelectric conversion element 21 with respect to the central axis direction Dm1 of the magnetic field at the initial position and a deviation angle of the arrangement direction of the second magnetoelectric conversion element 22 with respect to the central axis direction Dm2 of the magnetic field at the position after movement. Are equal to each other, the strength of the magnetic field received by the first magnetoelectric conversion element 21 from the magnet 50 at the initial position is substantially equal to the strength of the magnetic field received by the second magnetoelectric conversion element 22 from the magnet 50 at the moved position. It can be. As a result, when the detection target 140 rotates about the rotation axis Po by a predetermined angle θ, the detection accuracy with respect to the movement angle of the detection target 140 can be further increased.

  Such an effect is an effect when the movement of the detection target 140 is a rotation, but even when the detection target 140 moves linearly as in the first embodiment, the magnetic field center axis direction Dm1 at the initial position. The same effect can be obtained by making the deviation angle of the arrangement direction of the first magnetoelectric conversion element 21 with respect to the same and the deviation angle of the arrangement direction of the second magnetoelectric conversion element 22 with respect to the central axis direction Dm2 of the magnetic field at the moved position. Can be obtained.

  In addition, with respect to the movement of the detection target 140 as in the present embodiment, for example, the magnetosensitive direction Ds1 of the first magnetoelectric transducer 21 and the magnetosensitive direction Ds2 of the second magnetoelectric transducer 22 are represented by the magnetic field at the initial position. If it is set to coincide with the central axis direction Dm1 or set to coincide with the central axis direction Dm2 of the magnetic field at the position after movement, the first magnetoelectric conversion with respect to the central axis direction Dm1 of the magnetic field at the initial position There is a deviation between the inclination angle of the magnetic sensing direction Ds1 of the element 21 and the inclination angle of the magnetic sensing direction Ds2 of the second magnetoelectric conversion element 22 with respect to the central axis direction Dm2 of the magnetic field at the moved position. In such a case, there is a deviation between the strength of the magnetic field received by the first magnetoelectric conversion element 21 from the magnet 50 at the initial position and the strength of the magnetic field received by the second magnetoelectric conversion element 22 from the magnet 50 at the moved position. Would have occurred.

  On the other hand, in the position detection apparatus 101 of the present embodiment, the direction is shifted from the central axis direction Dm1 of the magnetic field at the initial position by the angle θ / 2 toward the central axis side of the magnetic field at the moved position. By setting the magnetic sensitive direction Ds1 of the first magnetoelectric conversion element 21 and the magnetic sensitive direction Ds2 of the second magnetoelectric conversion element 22, the magnetic sensitivity of the first magnetoelectric conversion element 21 with respect to the central axis direction Dm1 of the magnetic field at the initial position is set. The tilt angle in the direction Ds1 can be made equal to the tilt angle in the magnetosensitive direction Ds2 of the second magnetoelectric transducer 22 with respect to the central axis direction Dm2 of the magnetic field at the moved position.

  Then, the inclination angle of the magnetosensitive direction Ds1 of the first magnetoelectric conversion element 21 with respect to the central axis direction Dm1 of the magnetic field at the initial position, and the magnetosensitive direction of the second magnetoelectric conversion element 22 with respect to the central axis direction Dm2 of the magnetic field at the moved position. By equalizing the inclination angle of Ds2, the strength of the magnetic field received by the first magnetoelectric conversion element 21 from the magnet 50 at the initial position and the strength of the magnetic field received by the second magnetoelectric conversion element 22 from the magnet 50 at the moved position are set. Can be approximately equal. As a result, when the detection target 140 rotates about the rotation axis Po by a predetermined angle θ, the detection accuracy with respect to the movement angle of the detection target 140 can be further increased.

  Such an effect is an effect when the movement of the detection target 140 is a rotation, but even when the detection target 140 moves linearly as in the first embodiment, the magnetic field center axis direction Dm1 at the initial position. Is equal to the inclination angle of the magnetic sensing direction Ds1 of the first magnetoelectric conversion element 21 and the inclination angle of the magnetic sensing direction Ds2 of the second magnetoelectric conversion element 22 to the central axis direction Dm2 of the magnetic field at the position after movement. Similar effects can be obtained.

  As mentioned above, although embodiment of this invention has been described, this invention is not limited to said embodiment, In the range which does not deviate from the objective of this invention, it can change suitably.

  For example, in the embodiment of the present invention, the position detection devices 1 and 101 may be used for purposes other than those described above. For example, the position detection device 1 may be used for the purpose of detecting the position of the operation member of a push button type switch device. The position detection device 101 may be used for detecting the position of a member such as a swinging pendulum.

  In the embodiment of the present invention, the detection unit 10 is fixed to the holding member and the magnet 50 is not moved together with the detection targets 40 and 140, but the magnet 50 is fixed to the holding member and the detection unit 10 is detected to the detection target 40. , 140 may be moved. Even in such a case, if the relative distance between the magnet 50 and the detection unit 10 changes in the same manner as in this embodiment as the detection objects 40 and 140 move, the same effects as in this embodiment can be obtained. Can be obtained.

  In the first embodiment of the present invention, the predetermined movement of the detection targets 40 and 140 is not movement in the direction away from the detection unit 10 (forward) but movement in the direction approaching the detection unit 10 (rearward). It does not matter. In that case, the magnetoelectric conversion element 20 arranged in the front is the first magnetoelectric conversion element 21, and the magnetoelectric conversion element 20 arranged in the rear is the second magnetoelectric conversion element 22. Can be obtained.

  In the embodiment of the present invention, the position detection devices 1 and 101 may further include members other than those described above. For example, the position detection devices 1 and 101 may include a case member for housing the detection unit 10, an attachment member for attaching the case member to the holding member described above, and the like.

  In the embodiment of the present invention, the magnetoelectric conversion element 20 may be an element other than those described above. For example, the magnetoelectric conversion element 20 may be a Hall element, an element using electromagnetic induction, or the like.

  In the embodiment of the present invention, if correction is possible on the detection circuit 30 side, the moving distance of the magnet 50 accompanying the predetermined movement of the detection objects 40 and 140 and the distance between the two magnetoelectric transducers 20 Does not have to be exactly the same distance. In addition, the strength of the magnetic field received by the first magnetoelectric conversion element 21 from the magnet 50 at the initial position and the strength of the magnetic field received by the second magnetoelectric conversion element 22 from the magnet 50 at the moved position are not completely the same value. It doesn't matter.

  In the embodiment of the present invention, the position detection devices 1 and 101 detect whether or not the detection targets 40 and 140 have moved in a predetermined manner based on the strength of the magnetic field received by the magnetoelectric conversion element 20 from the magnet 50. In addition, it may be further detected whether or not the detection objects 40 and 140 have returned to the initial positions. For example, the strength of the magnetic field received by the second magnetoelectric conversion element 22 from the magnet 50 at the position after movement is stored as the second reference value, and the strength of the magnetic field received by the first magnetoelectric conversion element 21 from the magnet 50 is the second. It is possible to determine whether or not the detection objects 40 and 140 have returned to the initial positions.

  In the embodiment of the present invention, the position detection devices 1 and 101 compare the strength of the magnetic field received by the second magnetoelectric conversion element 22 from the magnet 50 with the reference value, so that the detection targets 40 and 140 are moved from the initial position. The amount of movement until a predetermined movement may be detected.

DESCRIPTION OF SYMBOLS 1 Position detection apparatus 10 Detection part 20 Magnetoelectric conversion element 21 1st magnetoelectric conversion element 21a Magnetosensitive surface 22 2nd magnetoelectric conversion element 22a Magnetosensitive surface 30 Detection circuit 101 Position detection apparatus

Claims (5)

In the position detection device including a detection unit that detects the movement of the detection target using the change accompanying the movement of the detection target of the magnetic field received from the magnet,
The detection unit has two magnetoelectric conversion elements,
The two magnetoelectric transducers are arranged at a distance corresponding to the amount of movement due to the predetermined movement of the detection target,
The distance from the magnet at the initial position to be detected to one of the two magnetoelectric transducers;
The distance from the magnet at the position after the movement of the detection target to the other magnetoelectric conversion element of the two magnetoelectric conversion elements is equal.
Position置検out device you characterized in that said two electromagnetic element is disposed. In the position detection device including a detection unit that detects the movement of the detection target using the change accompanying the movement of the detection target of the magnetic field received from the magnet,
The detection unit has two magnetoelectric conversion elements,
The two magnetoelectric transducers are arranged at a distance corresponding to the amount of movement due to the predetermined movement of the detection target,
A deviation angle in a direction from the magnet at the initial position of the detection target toward the one of the two magnetoelectric conversion elements with respect to the direction of the central axis of the magnetic field generated by the magnet at the initial position of the detection target;
Deviation angle of the direction from the magnet at the position after the movement of the detection target toward the other of the two magnetoelectric conversion elements with respect to the direction of the central axis of the magnetic field generated by the magnet at the position after the movement of the detection target To be equal to
Position置検out device you characterized in that said two electromagnetic element is disposed. In the position detection device including a detection unit that detects the movement of the detection target using the change accompanying the movement of the detection target of the magnetic field received from the magnet,
The detection unit has two magnetoelectric conversion elements,
The two magnetoelectric transducers are arranged at a distance corresponding to the amount of movement due to the predetermined movement of the detection target,
The predetermined movement of the detection target is a movement that rotates together with the magnet by a predetermined angle around the rotation axis.
Along the direction shifted from the direction of the central axis of the magnetic field generated by the magnet at the initial position of the detection target to the side of the central axis of the magnetic field generated by the magnet at the position after the movement of the detection target by an angle half the predetermined angle. And
Position置検out device you characterized in that said two electromagnetic element is disposed. In the position detection device including a detection unit that detects the movement of the detection target using the change accompanying the movement of the detection target of the magnetic field received from the magnet,
The detection unit has two magnetoelectric conversion elements,
The two magnetoelectric transducers are arranged at a distance corresponding to the amount of movement due to the predetermined movement of the detection target,
The inclination angle of the magnetosensitive direction of one of the two magnetoelectric transducers with respect to the direction of the central axis of the magnetic field generated by the magnet at the initial position of the detection target,
The inclination angle of the magnetosensitive direction of the other magnetoelectric conversion element of the two magnetoelectric conversion elements with respect to the direction of the central axis of the magnetic field generated by the magnet at the position after the movement of the detection target is equal.
It position置検out device you wherein the magneto-sensitive direction of the two magnetoelectric transducers has been set. In the position detection device including a detection unit that detects the movement of the detection target using the change accompanying the movement of the detection target of the magnetic field received from the magnet,
The detection unit has two magnetoelectric conversion elements,
The two magnetoelectric transducers are arranged at a distance corresponding to the amount of movement due to the predetermined movement of the detection target,
The predetermined movement of the detection target is a movement that rotates together with the magnet by a predetermined angle around the rotation axis.
The direction is the same as the direction shifted from the direction of the central axis of the magnetic field generated by the magnet at the initial position of the detection target to the side of the central axis of the magnetic field generated by the magnet at the position after the movement of the detection target. Like
It position置検out device you wherein the magneto-sensitive direction of the two magnetoelectric transducers has been set.