JP5529064B2 - Non-contact switch and magnetic sensor - Google Patents

Description

The present invention relates to a non-contact switch using a magnetic sensor and a magnetic sensor .

  As a non-contact switch, a proximity switch including a magnetic field sensitive sensor has been proposed (see, for example, Patent Document 1). This conventional proximity switch includes a permanent magnet having an NS pole at a base formed in a U-shape. In the U-shaped concave portion of the permanent magnet, a magnetic flux-free region (magnetic fieldless region) surrounded by three N poles is formed, and a magnetic field sensitive sensor sensitive to a magnetic field is attached in the magnetic fieldless region. ing. When the magnetic body is close to the two N poles of the pair of legs, a magnetic field is generated in the non-magnetic field region, and the switch circuit can be turned on / off by detecting this change in the magnetic field with a magnetic field sensitive sensor. .

Japanese Patent No. 2921603

  In the conventional proximity switch described in Patent Document 1, the U-shaped permanent magnets are not uniform in shape but irregular, and the magnetic poles are not arranged at uniform positions. The magnetic field applied by the magnet is distorted, and the permeance varies from part to part of the permanent magnet. As a result, demagnetization due to the temperature of the permanent magnet occurs non-uniformly and the direction of the magnetic field (direction of the magnetic vector) changes greatly, so that the switching position of the proximity switch is shifted.

An object of the present invention is to provide a non-contact switch and a magnetic sensor that can suppress malfunctions and increase detection accuracy.

[1] The present invention provides a magnet that generates a magnetic flux directed in a predetermined direction in a detection region, a magnetic sensor that is disposed in the detection region and detects a change in the direction of the magnetic flux due to the proximity of a magnetic member, and the magnetic A determination unit that determines on or off based on an output signal of the sensor, and the magnet has a reference curved surface that forms a first surface that is an N pole and a second surface that is an S pole. On the other hand, a shape having a predetermined thickness in the vertical direction is formed at each point of the reference curved surface, and magnetized by being magnetized in the vertical direction at each point. A contact switch is provided.

  Here, the reference curved surface refers to a curved surface shape that serves as a reference for the shape of the magnet. The shape of the magnet includes a symmetric shape, an asymmetric shape, or a combination of these on the first curved surface side serving as the N pole and the second surface side serving as the S pole with respect to the reference curved surface.

[2] In the invention described in [1] above, the magnet is formed in a U shape having a curved surface portion and a pair of extending portions extending in the same direction from the curved surface portion. And

[3] The present invention further includes a magnet for generating a magnetic flux directed in a predetermined direction in the detection region;
A magnetic detection element disposed in the detection region and detecting a change in the direction of the magnetic flux due to the proximity of a magnetic member, wherein the magnet has a first surface serving as an N pole and a second surface serving as an S pole. Is formed with a predetermined thickness in the vertical direction at each point of the reference curved surface, and is magnetized by being magnetized in the vertical direction at each point. A magnetic sensor is provided.

ADVANTAGE OF THE INVENTION According to this invention, while being able to suppress malfunction, the non-contact switch and magnetic sensor which can raise detection accuracy are obtained.

It is a front view showing typically an example of 1 composition of a non-contact switch concerning a 1st embodiment of the present invention. It is a side view of the non-contact switch in a 1st embodiment. (A) is the schematic showing the direction of the magnetic vector of the plane where MR sensor is arranged when the detected part which adjoins the 1st embodiment adjoins, (b) is the detected part separated It is the schematic showing the direction of the magnetic vector of the plane where the MR sensor at the time is arranged. It is the schematic of the bridge circuit in 1st Embodiment. It is a figure which shows an example of the functional block structure of the brake device using MR sensor in 1st Embodiment. It is a front view which shows typically one structural example of the non-contact switch in 2nd Embodiment. It is a front view which shows typically one structural example of the non-contact switch in 3rd Embodiment. It is the schematic of the bridge circuit in 4th Embodiment.

  Preferred embodiments of the present invention will be specifically described below with reference to the accompanying drawings.

[First Embodiment]
(Configuration of solid state switch)
In FIG. 1, reference numeral 10 indicating the whole exemplifies a configuration example of a non-contact switch (hereinafter referred to as “ non-contact switch ”) that detects the magnetic force of the magnet in a non-contact manner. The contactless switch 10 includes a sensor 11, a substrate 12, and a magnetic body 13. The sensor 11 has a magnet 14 and two MR sensors 15 and 15. The substrate 12, the magnet 14, and the MR sensor 15 are accommodated in, for example, a non-magnetic casing (not shown) and molded with a resin material.

(Composition of magnet)
The most main configuration of the contactless switch 10 in the first embodiment is the structure of the magnet 14. The magnet 14 has a first surface that is an N pole and a second surface that is an S pole. A shape having a predetermined thickness (width) W1, W2 in the vertical direction at each point of the reference curved surface CL (reference curve CL forming the reference curved surface) that forms the first surface and the second surface. It is formed and magnetized by being magnetized in the vertical direction.

  According to the illustrated example, the magnet 14 may be a plastic magnet formed by adding neodymium to PPS resin, for example, and a magnetic field formed in a cylindrical shape having a uniform shape in the circumferential direction by compression molding or injection molding. It is comprised as a generation | occurrence | production cylinder part (henceforth "the cylindrical magnet 14"). The cylindrical magnet 14 includes a cylindrical portion 14a having an annular opening end surface perpendicular to the central axis O at both ends. The cylindrical portion 14a is formed in an arc shape in which the curvature of the inner peripheral surface and the curvature of the outer peripheral surface have the same curvature.

  As shown in FIGS. 1 and 2, the cylindrical magnet 14 has a first surface serving as an N pole on the radial outer peripheral surface side centered on the central axis O of the cylindrical portion 14 a and a radial inner peripheral surface. It has the structure which has the 2nd surface used as the S pole in the side. According to the illustrated example, each of the radial thicknesses W1 and W2 of the cylindrical portion 14a is formed constant in the circumferential direction around the reference curved surface CL, and each half of the cylindrical portion 14a in the cylindrical magnet 14 in the radial direction is respectively formed. N pole and S pole are magnetized.

  In this way, each half of the cylindrical portion 14a in the cylindrical magnet 14 in the radial direction is magnetized to the N pole and the S pole, so that the magnetic flux line Z appears from the N pole to the S pole. Since this magnetic flux line Z becomes the direction of the magnetic field, the direction of the magnetic field (direction of the magnetic flux line Z) is the radial direction of the cylindrical portion 14a. In the illustrated example, the magnetic flux line Z passes downward on the outer peripheral surface side of the cylindrical portion 14a and passes upward on the inner peripheral surface side of the cylindrical portion 14a.

  As shown in FIGS. 1 and 2, the cylindrical magnet 14 is magnetized by using a magnetizing member disposed outside the cylindrical portion 14a, for example. As an example, for example, a predetermined magnetic field is applied by bringing a magnetizing member close to the opposing end surface of the cylindrical portion 14a, and the magnetic pole N and the magnetic pole are arranged in the radial direction about the central axis O of the cylindrical portion 14a. S is magnetized. In the illustrated example, the cylindrical portion 14a is magnetized from the radially outer peripheral surface side to the radially inner peripheral surface side. On the contrary, an S pole is formed on the radially outer peripheral surface side of the cylindrical portion 14a. Of course, it is possible to function even if an N pole is formed on the radially inner surface side.

  Although the curvature of the inner and outer peripheral directions of the cylindrical magnet 14 according to the illustrated example is formed on the same curved surface, the present invention is not limited to this. In the present invention, the cylindrical magnet 14 may have a curved surface shape having different curvatures in the inner and outer circumferential directions, or a shape including a flat surface having a curved surface having zero curvature in the inner and outer circumferential directions. Further, if the magnetic field intersects in a direction perpendicular to the reference curve CL forming the reference curved surface CL, the radial thicknesses W1 and W2 of the cylindrical portion 14a in the cylindrical magnet 14 in the illustrated example are the cylindrical portion 14a. The reference curved surface CL may be asymmetrical, symmetric, or a combination thereof.

(Substrate structure)
The substrate 12 is made of, for example, silicon and is formed in a rectangular shape as shown in FIGS. Two MR sensors 15 and 15 that are magnetic sensors are formed on the surface of the substrate 12 with a vertical plane including the central axis O of the cylindrical portion 14a of the cylindrical magnet 14 as a symmetry plane. The width of the substrate 12 is formed smaller than the inner diameter of the cylindrical portion 14 a so that the substrate 12 can be inserted into the cylindrical portion 14 a of the cylindrical magnet 14. Inside the cylindrical portion 14a, the opposing long side portion of the substrate 12 is disposed on a plane including the central axis O of the cylindrical portion 14a, so that the MR sensors 15 and 15 do not move relative to the cylindrical magnet 14. The substrate 12 is fixed via a fixing member (not shown).

(Configuration of magnetic material)
The magnetic body 13 is formed of, for example, an iron material or the like. As shown in FIGS. 1 and 2, the magnetic body 13 has a magnetic field magnitude (strength) close to or away from the sensor 11. To be detected. A configuration in which the contactless switch is turned on and off depending on the position of the magnetic body 13 can be effectively obtained.

(Sensor configuration)
1 and 2, one MR sensor 15 of the pair of MR sensors 15 and 15 will be described. The other MR sensor 15 also has the same shape and structure. This MR sensor 15 has a magnetoresistive element manufactured by a photolithographic method or the like using a ferromagnetic material such as permalloy.

  Referring to FIG. 3, an example of a magnetic field applied to the magnetic body 13 and the cylindrical magnet 14 is schematically shown by an arrow (magnetic vector Z) in FIG. 3. 3A shows a magnetic field when the distance d between the magnetic body 13 and the cylindrical magnet 14 shown in FIG. 1 is 1 mm, and FIG. 3B shows a magnetic field when the distance d is 4 mm. ing. The length of the magnetic vector Z is proportional to the strength of the magnetic field, but the size of the arrow is not related to the strength of the magnetic field.

  As shown in FIGS. 3A and 3B, four magnetic fields are formed on the cylindrical magnet 14. In the four magnetic field switching regions, a first region A and a second region B are formed in which the magnetic vector Z faces in a direction transverse to the central axis O of the cylindrical magnet 14 (radial direction). The first and second areas A and B are detection areas for detecting a change in magnetic field, and MR sensors 15 and 15 are arranged in these areas A and B, respectively.

  As shown in FIG. 3A, the magnetic field applied to the MR sensors 15 and 15 is in a state where the magnetic body 13 is in an initial position close to the cylindrical magnet 14, and as shown in FIG. The magnetic body 13 moves away from the cylindrical magnet 14 and changes from a state where it is not affected by the magnetic body 13. This change in the magnetic vector Z is detected by the MR sensors 15 and 15.

  When the magnetic body 13 is close to the cylindrical magnet 14, the magnetic field applied by the magnetic body 13 and the cylindrical magnet 14 passes through the inner peripheral surface side of the cylindrical portion 14a upward as shown in FIG. It is formed toward the body 13. The first and second regions A and B are regions in which the direction of the magnetic vector Z is directed in a direction transverse to the central axis O of the cylindrical magnet 14, and the direction of the magnetic vector Z is approximately the MR sensor 15 and 15. If it becomes 0 degree, an output voltage will not generate | occur | produce in MR sensors 15 and 15, or an output voltage will become small.

  On the other hand, when the magnetic body 13 is separated from the cylindrical magnet 14, the magnetic field applied by the cylindrical magnet 14 moves as shown in FIG. As the magnetic body 13 moves away from the cylindrical magnet 14 and the magnetic field of the cylindrical magnet 14 moves, the direction of the magnetic vector Z passing through the MR sensors 15 and 15 in the first and second regions A and B changes. Since the magnetoresistive values of the MR sensors 15 and 15 change according to the direction of the magnetic vector Z of the magnetic field, a change in the output voltage can be detected.

  This makes it possible to stably detect a change in the distance d of the magnetic body 13 with respect to the cylindrical magnet 14, and the MR sensors 15 and 15 can output a voltage corresponding to the magnetic field direction. As a result, it becomes easy to detect a change in the magnetoresistance value based on a change in the direction of the magnetic vector Z of the magnetic field.

  As shown in FIG. 4, the MR sensor 15 has four magnetoresistive elements R1 to R4, and the magnetoresistive elements R1 to R4 constitute a bridge circuit 16. The magnetoresistive element R1 and the magnetoresistive element R3 are connected in series with each other, and the magnetoresistive element R2 and the magnetoresistive element R4 are connected in series with each other. The magnetoresistive elements R1, R3 and the magnetoresistive elements R2, R4 are connected in parallel to each other.

  As shown in FIG. 4, an input terminal 16a connected to the power supply unit is formed between the magnetoresistive element R1 and the magnetoresistive element R3. A ground terminal 16b is formed between the magnetoresistive element R2 and the magnetoresistive element R4. Between the magnetoresistive element R1 and the magnetoresistive element R2, an output terminal 16c from which a midpoint potential V1 is output is formed. Between the magnetoresistive element R3 and the magnetoresistive element R4, an output terminal 16d from which a midpoint potential V2 is output is formed.

  As the magnetic body 13 moves, the magnetic field of the cylindrical magnet 14 moves, so that the direction of the magnetic vector Z of the magnetic field applied to the magnetoresistive elements R1 to R4 changes. By changing the magnetic resistance values of the magnetoresistive elements R1 to R4, the midpoint potential V1 and the midpoint potential V2 change. A difference value between the midpoint potential V1 and the midpoint potential V2 is output as the output voltage V.

  The arrangement position of the MR sensor 15 is not limited to the illustrated example, and the direction of the magnetic vector Z is directed to the lateral direction with respect to the central axis O of the cylindrical magnet 14, and the magnetic material 13 approaches and moves away from the magnetism. Any region where the direction of the vector changes can be freely arranged in a plane parallel to the substrate, for example. As the magnetic sensor, for example, a Hall element or a Hall IC can be applied.

(Configuration of stop lamp switch)
The sensor 11 configured as described above can be effectively used as a non-contact switch used for position detection of a moving body. As an example, there is a stop lamp (brake lamp) switch used for detecting the position of a brake pedal of a vehicle, for example. Referring to FIG. 5, FIG. 5 illustrates an example of a functional block configuration of the brake device. In FIG. 5, the same member names and symbols are assigned to substantially the same members as those in the first embodiment.

  The stop lamp switch 100 includes a sensor 11 fixed to a vehicle body (not shown) and a magnetic body 13 fixed to an arm portion of a brake pedal 101. The brake pedal 101 is provided such that an upper end portion of an arm portion is movable in the longitudinal direction of the vehicle body about a support shaft with respect to a bracket fixed to a frame of a vehicle body (not shown).

Sensor 11 is connected likewise via a connector not shown to the control IC 18 as illustrated such have decisions section threshold 17. The sensor 11, the magnetic body 13, and the control IC 18 constitute a non-contact switch 10. The switching point (on / off) of the stop lamp switch 100 can be controlled through an ECU (Electronic Control Unit) which is a control unit of the stop lamp, depending on the arrangement position of the sensor 11 and the magnetic body 13. Note that the MR sensor 15 and the control IC 18 may be integrated into a single chip, which may be an IC chip, and the IC chip may be a resin-molded mold IC.

The stop lamp switch 100 detects the presence or absence of a brake operation based on the position of the magnetic body 13 that changes the magnetic field direction of the cylindrical magnet 14 of the sensor 11. The position of the magnetic body 13 when the brake pedal 101 is not depressed is the reference position. The control IC 18 compares the output voltage V from the sensor 11 with the threshold value 17 to determine whether or not a brake operation has been performed. When it is determined that the brake operation has been performed, the brake lamp 102 is turned on via the ECU 103.

In a state where the brake pedal 101 is not depressed, an output level L detection signal is output. In the control IC 18, it is determined whether or not this detection signal is equal to or less than a threshold value. When the output level is L, a determination signal (off signal) indicating that the output level is equal to or less than the threshold value is output. Thereby, this OFF signal is output to ECU103. In a brake lamp drive circuit (not shown), when an off signal is input, the brake lamp 102 is turned off.

On the other hand, when the brake pedal 101 is depressed, the magnetic pedal 13 moves away from the cylindrical magnet 14 of the sensor 11 by moving the brake pedal 101 forward of the vehicle body about the support shaft of the arm portion. In this state, a detection signal of output level H is output. It is determined in the control IC 18 whether or not this detection signal is equal to or less than a threshold value. When the output level is H, a determination signal (ON signal) indicating that the output level is equal to or higher than the threshold value is output. As a result, this ON signal is output to the ECU 103. In the brake lamp drive circuit, the brake lamp 102 is turned on based on the ON signal.

The output voltage V from the sensor 11 to the control IC 18 is output for each of the two MR sensors 15, 15, or is output from one of the two MR sensors 15, 15, thereby braking. You may employ | adopt the structure which judges the presence or absence of operation. When one of the two MR sensors 15, 15 fails, the control IC 18 turns on / off (turns on) the brake lamp 102 based on the output voltage V from the other MR sensor 15 that does not fail.・ Off) can be determined. The output voltage V is a configuration for determining whether the brake lamp 102 is turned on or off (on / off) based on a value obtained by adding the outputs of the two MR sensors 15 or 15 or an average value of the two outputs. Of course, it is also good. Further, the ECU 103 may be provided with a function of performing determination recognition of whether or not the control IC 18 has failed.

(Effects of the first embodiment)
The non-contact switch 10 according to the first embodiment has a predetermined thickness W1, W2 in the vertical direction at each point of the reference curve CL that forms the reference curved surface that forms the N pole face and the S pole face. It is formed in the cylindrical shape which has. In the illustrated example, the cylindrical magnets 14 have a uniform shape, and the magnetic poles NS are equally arranged half by half in the radial direction. Therefore, in addition to the above effects, the following effects are obtained.
(1) It is possible to suppress detection errors due to distortion of the magnetic field applied from the cylindrical magnet 14.
(2) The direction of the magnetic field from the cylindrical magnet 14 is uniform over a wide range, and a magnetic field having a uniform magnetic field direction can be formed in the installation space around the MR sensor 15.
(3) Compared with a conventional U-shaped permanent magnet, the assemblability can be improved.
(4) Since the proximity / separation of the magnetic body 13 is detected in a stable region in which the magnetic flux direction is in a lateral direction with respect to the central axis O of the cylindrical magnet 14, malfunction can be suppressed. In addition, since detection is performed by the two MR sensors 15 and 15, detection accuracy can be increased.
(5) Since the demagnetization due to the temperature of the cylindrical magnet 14 can be compensated, accurate control corresponding to the command value can be realized.

[Second Embodiment]
Even in the second embodiment, there is no difference in the basic configuration from the non-contact switch 10 according to the first embodiment. In FIG. 6, the main difference from the first embodiment is that in the first embodiment, the configuration in which the magnetic field generating cylinder is formed in a cylindrical shape is the same as that of the second embodiment. In the form, the magnetic field generating cylinder is formed in a half-cylindrical shape. In FIG. 6, the same member name and reference numeral are assigned to substantially the same members as those in the first embodiment. Therefore, the detailed description regarding these members is omitted.

  In the example of illustration, the magnet 21 consists of one half cylinder part 21a divided | segmented into two along the central axis O of the cylinder part. The inner and outer peripheral surfaces of the half cylindrical portion 21a are formed as concentric semicircular arc surfaces in which the curvature of the inner peripheral surface and the curvature of the outer peripheral surface have the same curvature. The substrate 21 is fixed to the magnet 21 via a fixing member (not shown) so that the MR sensors 15 and 15 formed on the surface of the substrate 12 do not move relative to the half cylinder portion 21a. Two MR sensors 15 and 15 are arranged on the substrate 12 with a vertical plane including the central axis O as a symmetrical plane. In the illustrated example, the curvatures in the inner and outer peripheral directions of the half cylindrical portion 21a are formed on the same curved surface, but the present invention is not limited to this, as in the first embodiment. is there.

(Effect of the second embodiment)
Even in the non-contact switch 10 according to the second embodiment, the halved cylindrical portion 21a of the magnet 21 has a uniform shape, and the magnetic poles are equally arranged half by half in the radial direction. The same effect as in the first embodiment can be obtained.

[Third Embodiment]
Even in the third embodiment, there is no difference in the basic configuration from the non-contact switch 10 according to the first embodiment. In FIG. 7, in the third embodiment, the magnetic field generating cylinder is formed in a U shape. In FIG. 7, members that are substantially the same as those in the first and second embodiments are given the same member names and reference numerals, and detailed descriptions thereof are omitted.

  In the illustrated example, the magnet 22 has a U-shape having a half-cylindrical portion 21a that is a curved surface portion, and plate-like extension portions 22a and 22a that extend in the same direction from both end surfaces of the half-cylindrical cylinder portion 21a. Is formed. The substrate 12 is fixed inside the magnet 21 via a fixing member (not shown). The MR sensors 15 and 15 formed on the surface of the substrate 12 and the half-cylindrical portion 21a do not move relative to each other. Two MR sensors 15 and 15 are arranged on the substrate 12 with a vertical plane including the central axis O as a symmetrical plane. Even in the third embodiment, the curvature in the inner and outer circumferential directions of the half cylinder portion 21a is formed on the same curved surface, but is not limited to this.

(Effect of the third embodiment)
Even in the non-contact switch 10 according to the third embodiment, since the magnetic poles of the magnets 22 are arranged uniformly, the same effect as the first embodiment can be obtained.

[Fourth Embodiment]
In the first embodiment, the bridge circuit 16 is used for the contactless switch 10. However, in the fourth embodiment, the half bridge circuits 19 a and 19 b are used for the contactless switch 10. . In FIG. 8, members that are substantially the same as those in the first embodiment are given the same member names and symbols. Therefore, the detailed description regarding these members is omitted.

  As shown in FIG. 8, the MR sensor 15 includes half bridge circuits 19a and 19b. The half bridge circuit 19a is configured by magnetoresistive elements R1 and R2, and is arranged in the first region A or the second region B shown in FIG. One half-bridge circuit 19b is configured by magnetoresistive elements R3 and R4, and is arranged in the second region B or the first region A shown in FIG.

  The half bridge circuit 19 a outputs the first output voltage V according to the distance d between the magnetic body 13 and the cylindrical magnet 14. One half bridge circuit 19b is configured to output a second output voltage V2 different from the first output voltage V1 according to the distance d. The output voltage V1 of the half bridge circuit 19a can be inverted using an operational amplifier (not shown), and the inverted output voltage and the output voltage V2 of the half bridge circuit 19b can be added.

The MR sensor 15 according to the fourth embodiment can be effectively used for detecting the position of the brake pedal 101 of the vehicle as shown in FIG. By comparing the output voltage from the MR sensor 15 with the threshold value 17 of the control IC 18, it is possible to determine the presence or absence of a brake operation in the brake device, and to control the turning on and off of the brake lamp 102 via the ECU 103. . The half-bridge circuits 19a and 19b may be molded independently and arranged in the first region A and the second region B. As one MR sensor, the half-bridge circuits 19a and 19b are formed in the first region A and the second region B. It may be molded so that the circuits 19a and 19b are included.

(Effect of the fourth embodiment)
Since the half-bridge circuits 19a and 19b are arranged in the first area A and the second area B, the presence or absence of the brake operation can be determined stably as in the first embodiment. .

  In the embodiment described above, the control of turning on and off the brake lamp 102 has been described. However, the present invention is not limited to this. For example, the lighting control in the storage box of the instrument panel of the vehicle or the vehicle Of course, the present invention can also be applied to other controls.

  As is clear from the above description, the typical configuration example of the non-contact switch of the present invention has been described with reference to the embodiment, the modification, and the illustrated example, but the embodiment, the modification, The illustrated examples are not intended to limit the claimed invention. It should be noted that not all the combinations of the features described in the above embodiments, modifications, and illustrated examples are essential to the means for solving the problems of the present invention. Of course, various configurations are possible within the scope of this technical idea.

DESCRIPTION OF SYMBOLS 10 ... Solid state switch, 11 ... Sensor, 12 ... Board | substrate, 13 ... Magnetic body, 14, 21, 22 ... Magnet, 14a ... Cylindrical part, 15 ... MR sensor, 16 ... Bridge circuit, 16a ... Input terminal, 16b ... Ground Terminals, 16c, 16d ... Output terminals, 17 ... Threshold, 18 ... Control IC , 19a, 19b ... Half bridge circuit, 21a ... Half cylindrical part, 22a ... Extension part, 100 ... Stop lamp switch, 101 ... Brake pedal, DESCRIPTION OF SYMBOLS 102 ... Brake lamp, 103 ... ECU , A ... 1st area | region, B ... 2nd area | region, CL ... Reference | standard curved surface, d ... Distance, O ... Center axis, R1-R4 ... Magnetoresistive element, V ... Output voltage, V1, V2: Midpoint potential, W1, W2 ... Thickness, Z ... Magnetic flux line (magnetic vector)

Claims (3)

A magnet for generating a magnetic flux directed in a predetermined direction in a detection region;
A magnetic sensor that is disposed in the detection region and detects a change in the direction of the magnetic flux due to the proximity of a magnetic member;
A determination unit that determines on or off based on an output signal of the magnetic sensor,
The magnet has a predetermined thickness in a vertical direction at each point of the reference curved surface with respect to the reference curved surface forming the first surface serving as the N pole and the second surface serving as the S pole. A non-contact switch having a shape and magnetized by being magnetized in the vertical direction at each of the points.   The non-contact switch according to claim 1, wherein the magnet is formed in a U shape having a curved surface portion and a pair of extending portions extending in the same direction from the curved surface portion. A magnet for generating a magnetic flux directed in a predetermined direction in a detection region;
A magnetic detection element disposed in the detection region and detecting a change in the direction of the magnetic flux due to the proximity of a magnetic member;
The magnet has a predetermined thickness in a vertical direction at each point of the reference curved surface with respect to the reference curved surface forming the first surface serving as the N pole and the second surface serving as the S pole. A magnetic sensor having a shape and magnetized by being magnetized in the vertical direction at each of the points.

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