JP2008267922A - Position sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a position sensor capable of improving the detection accuracy while reducing the manufacturing cost and the size, and facilitating the mounting work. <P>SOLUTION: This position sensor includes a plurality of detecting coils L that are disposed in a moving body 100 moving in a predetermined route, and are arranged near a moving region of the section 110 to be detected in a shape where their center axes X are arranged orthogonally in the moving direction of the metal section 110 to be detected to be moved with the moving body 100 in the direction along the center axis M and they are arranged along the center axis M of the section 110 to be detected, and a plurality of determining sections that are disposed in a shape corresponding to the plurality of detecting coils L, respectively, and determine whether the section 110 to be detected is positioned in a detection range of the detecting coils L. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a non-contact type position sensor using a detection coil.

  Conventionally, a non-contact type position sensor using a detection coil has been proposed. As shown in FIG. 13, this type of position sensor has a moving body 100 that moves linearly so as to move along a predetermined path. A detection unit 400 having a cylindrical coil bobbin 300 having an insertion hole 310 that is movably inserted in the movement direction and a hollow detection coil 200 provided in the coil bobbin 300 so as to surround the insertion hole 310, is provided. Based on a change in impedance of the detection coil 200 caused by a physical displacement of the moving body 100 inside the detection coil 200 (that is, a volume change of the moving body 100 located in the detection coil 200), an electrical signal corresponding to the physical displacement. Is provided (see, for example, Patent Document 1).

  By the way, in the position sensor as described above, for example, is a linear solenoid valve (not shown) used in a hydraulic control device (hydraulic control circuit) of an automatic transmission (automatic transmission) such as a vehicle operating normally? It is also used to detect whether or not.

  Here, as shown in FIG. 13, the linear solenoid valve is formed as a moving body 100 in a bar shape (round bar shape) having a uniform cross-sectional area in a plane orthogonal to the axial direction (left-right direction in FIG. 13) by metal. Whether or not the linear solenoid valve is operating normally is determined based on whether or not the shaft for driving the valve is provided and the shaft is located at a predetermined position.

  Since such a shaft has one end connected to a valve (not shown) and the other end connected to a driving device (not shown) that linearly moves the shaft, As shown in FIG. 13, the position sensor can be arranged so that the moving body 100 penetrates the insertion hole 310 of the coil bobbin 300, but cannot be arranged so that the moving body 100 enters and exits the insertion hole 310 of the coil bobbin 300. . In the state where the moving body 100 is inserted in the insertion hole 310 of the coil bobbin 300, the volume of the moving body 100 located in the detection coil 200 is not changed by the movement of the moving body 100, and therefore the position of the moving body 100 is detected. Can not.

  Therefore, in detecting the position of such a moving body 100, a detected part 110 provided on the moving body 100 and moved together with the moving body 100 is used. The detected portion 110 shown in FIG. 13 is a disk-shaped member having a radius larger than the radius of the moving body 100 (that is, the cross-sectional area in the plane is different from that of the moving body 100). Thus, the central axis is formed to coincide with the central axis of the moving body 100. Note that both the moving body 100 and the detected part 110 have a perfect circular cross section in a plane orthogonal to the central axis.

If such a detected part 110 is used, the detection coil 200 is caused by physical displacement of the detected part 1110 inside the detection coil 200 (that is, volume change of the detected part 110 located in the detection coil 200). The position of the detected part 110 can be detected based on the impedance change, and the position of the moving body 100 can be determined from the detection result.
JP 2006-317284 A

  However, when determining the position of the moving body 100 using the detected part 110 as described above, since the moving body 100 penetrates the detection coil 200, the impedance of the detection coil 200 is air core. Since there is a large change compared to a certain case, the amount of change in impedance when the detected portion 110 is positioned inside the detection coil 200 is reduced, and as a result, the detection accuracy of the position of the detected portion 110 is reduced. There was a problem of getting worse.

  As one method for solving such a problem, it has been proposed to increase the number of turns of the detection coil 200 and increase the length of the detection coil 200 in the central axis direction (winding axis direction). Another problem arises, such as an increase in manufacturing cost and an increase in size.

  Further, in order to use such a position sensor, it is necessary to penetrate the moving body 100 through the detection coil 200. Therefore, when the moving body 100 is disposed at a predetermined position with respect to the apparatus (for example, a hydraulic control apparatus). In this case, the position sensor must be installed in the moving body 100 in advance. For this reason, there is a problem in that the assembly order of the devices is not flexible and the position sensor cannot be easily attached.

  The present invention has been made in view of the above points, and it is an object of the present invention to provide a position sensor that can improve the detection accuracy and reduce the manufacturing cost and reduce the size, and can be easily attached.

  In order to solve the above-mentioned problem, the invention of claim 1 is a position sensor that is provided on a moving body that moves along a predetermined path and detects the position of a metal detected portion that is moved together with the moving body. A plurality of detection coils arranged in the vicinity of the movement region of the detected part in a form aligned with the moving direction along the central axis in a direction crossing the moving direction of the detected part, and corresponding to each of the plurality of detection coils And a detection circuit section having a plurality of determination sections for determining whether or not the detected section is located within the detection range of the detection coil.

  According to the first aspect of the present invention, a plurality of detection coils having a central axis along the direction intersecting the moving direction of the detected part are arranged in the vicinity of the moving region of the detected part in the moving direction. Therefore, since the position of the moving body can be detected depending on which impedance of the detection coil has changed, what is the conventional example in which the amount of change in the impedance of the detection coil corresponds to the amount of insertion of the detected part into the detection coil? In contrast, it is not necessary to increase the number of turns of the detection coil in order to improve the detection accuracy. As a result, the detection accuracy can be improved while reducing the manufacturing cost and reducing the size. In addition, since it is not necessary to penetrate the moving body to the detection coil, the attaching operation can be easily performed.

  According to a second aspect of the present invention, in the first aspect of the invention, a position determination unit that determines the position of the moving body based on a combination of the determination results of the plurality of determination units is provided.

  According to the invention of claim 2, since the position of the moving body is determined by combining the determination results of the plurality of determination units, the position of the moving body is determined using only the determination result of any of the plurality of determination units. Compared to the case, the position of the moving body can be detected more precisely.

  According to a third aspect of the present invention, in the second aspect of the invention, the detection circuit unit is configured to output a detection signal having a different potential according to a combination of the determination results of the plurality of determination units, and the position determination unit is The position of the moving object is determined based on the potential of the detection signal of the circuit unit.

  According to the invention of claim 3, since only one signal line is required to transmit the detection signal of the detection circuit unit to the position determination unit, the detection circuit unit individually detects the determination results of the plurality of determination units. Unlike the case of outputting as a signal, it is not necessary to provide as many ports for connecting signal lines as the number of determination units in the position determination unit, so that the configuration of the position determination unit can be simplified and the manufacturing cost can be reduced.

  According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the detected portion located within the detection range of one of the detection coils at both ends in the moving direction among the plurality of detection coils. However, the detection coil includes a stopper portion that restricts movement of the detection coil to a side opposite to the side facing the other detection coil by abutting against the detected portion.

  According to the invention of claim 4, since the position of the moving body can be specified even if the detected portion is not located within the detection range of any of the detection coils, the position of the moving body is confused. And the position of the moving body can be accurately detected.

  According to a fifth aspect of the present invention, in any one of the first to third aspects of the present invention, one of the detection coils at both ends in the moving direction among the plurality of detection coils has a detection range in the detection coil. The present invention is characterized in that it is formed in a shape that extends to the boundary of the moving range of the detected portion on the side opposite to the side facing the other detection coils.

  According to the invention of claim 5, since the position of the moving body can be specified even when the detected portion is not located within the detection range of any of the detection coils, the position of the moving body is confused. And the position of the moving body can be accurately detected.

  In the invention of claim 6, in the invention of any one of claims 1 to 5, in the detection coils at both ends in the moving direction among the plurality of detection coils, the side opposite to the side facing the other detection coils. Is provided with an outer shield member for magnetic shielding.

  According to the sixth aspect of the present invention, the detection coil can be prevented from being affected by the metal member existing around the moving body, so that the detection accuracy can be prevented from deteriorating.

  The invention according to claim 7 is the invention according to any one of claims 1 to 6, wherein at least adjacent detection coils are arranged so as not to overlap in a plane orthogonal to the moving direction. To do.

  According to the seventh aspect of the present invention, it is possible to prevent adjacent detection coils from interfering with each other magnetically, so that the detection accuracy can be improved.

  According to an eighth aspect of the present invention, in the seventh aspect of the present invention, the adjacent detection coils are configured to have the same outer diameter, and the distance between the central axes is greater than 0 and less than the outer diameter. It is characterized by being arranged.

  According to the invention of claim 8, since the interval between the adjacent detection coils can be set to be equal to or smaller than the outer diameter of each of the adjacent detection coils, the position of the moving body can be detected more precisely.

  The invention of claim 9 is characterized in that, in the invention of any one of claims 1 to 8, a core made of a magnetic material is arranged inside the detection coil.

  According to the ninth aspect of the invention, if the number of turns of the detection coil is the same, the magnetic flux can be made larger than that of the air-core detection coil, so that the amount of change in the impedance of the detection coil can be increased, and the detection accuracy can be improved.

  The present invention has an effect that the detection accuracy can be improved while the manufacturing cost is reduced and the size is reduced, and the mounting operation can be easily performed.

(Embodiment 1)
The position sensor of this embodiment is a non-contact type position sensor used for detecting whether or not a linear solenoid valve used in a hydraulic control device of an automatic transmission such as a vehicle is operating normally. is there. Here, for example, as shown in FIG. 5, the hydraulic control device has a body 500 in which a flow path 510 for driving oil 600 is provided, and the moving body 100 is provided in the flow path 510 of the body 500. It has been.

  As shown in FIG. 1A, the position sensor intersects with the central axis M of the detected part 110 along the moving direction of the detected part 110 (left and right direction in FIG. 1A) (orthogonal in the illustrated example). A plurality of (located in the vicinity of the moving region of the detected part 110 (a space part through which the detected part 110 passes as the moving body 100 moves) along the direction of the center axis X and aligned with the moving direction. In this embodiment, two detection coils L and a plurality of detection coils L are provided corresponding to each of the plurality of detection coils L, and a plurality of determinations are made as to whether or not the detected portion 110 is located within the detection range of the detection coils L. A detection unit 1 (see FIG. 2) including a detection circuit unit 2 (see FIG. 4) having a determination unit 20 and a main body unit 3 (see FIG. 2) provided with the detection coil L and the detection circuit unit 2 is provided. In addition, the position determination unit 60 (see FIG. 4) Eteiru.

  In the following description, for simplification of description, the upward direction in FIG. 2A is the upward direction of the detection unit 1 of the position sensor, the downward direction in FIG. The left direction in 2 (a) is defined as the forward direction of the detection unit 1, and the right direction in FIG. 2 (a) is defined as the backward direction of the detection unit 1, but this is not intended to limit the usage form of the detection unit 1. . Moreover, since the moving body 100 and the detected part 110 are the same as those described in the above-described conventional example, description thereof will be omitted.

  The main body 3 is, for example, a resin molded product made of an insulating resin material, and includes a barrel 30 formed in a cylindrical shape with the vertical direction as the central axis direction, as shown in FIG. .

  The body part 30 is provided with a storage part (not shown) in which the detection circuit part 2 is stored. For example, an opening shape in a plane orthogonal to the front-rear direction is formed in a rectangular shape, and the detection circuit unit 2 is fixed to the bottom surface portion (not shown). Further, as shown in FIGS. 2A and 2B, a groove portion 30 a to which an O-ring (not shown) is attached is formed in the trunk portion 30 so as to go around the outer peripheral surface of the trunk portion 30. .

  A coil holding part 31 provided with two detection coils L is integrally provided on the lower surface side of the body part 30. For example, the coil holding portion 31 is formed in a hollow rectangular plate shape whose thickness direction is the front-rear direction, and has a semicircular cutout on the lower end side thereof having a diameter larger than the outer diameter of the detected portion 110. Thus, an insertion part 31a through which the detected part 110 is inserted so as to be movable in the movement direction is provided. In the following description, in order to distinguish the detection coils L as necessary, the front detection coil L is represented by reference numeral L1 and the rear detection coil L is represented by reference numeral L2, and if necessary, the center of the detection coil L In order to distinguish the axis X, the central axis X of the detection coil L1 is represented by the symbol X1, and the central axis X of the detection coil L2 is represented by the symbol X2. Further, in FIG. 3, for the sake of simplification, the coil holding portion 31 is illustrated in a form in which the internal shape is omitted.

  Here, the detection coil L is formed in a cylindrical shape by winding an electric wire along the central axis X. As shown in FIGS. The axes X1 and X2 are along the direction orthogonal to the direction along the central axis M of the detected unit 110 (that is, the moving direction of the detected unit 110), and overlap in the plane orthogonal to the moving direction of the detected unit 110 It is arranged in the coil holding part 31 in such a way that it does not. Therefore, in the coil holding unit 31, a range that is approximately equal to the range that overlaps the detection coil L in the direction along the central axis X is the detection range of the detection coil L in the moving direction of the detected unit 110. Further, the detection coils L1 and L2 are arranged in the coil holding portion 31 so as to be line symmetric with respect to the central axis of the trunk portion 30. Note that the detection coil L does not necessarily have to have the central axis X along the direction orthogonal to the moving direction of the detected part 110, but may be along the direction intersecting the moving direction. It is preferable to follow the direction that is orthogonal to the moving direction (which may be considered to be orthogonal rather than orthogonal in a strict sense).

  Furthermore, the detection coils L1 and L2 are configured to have the same outer diameter, and as shown in FIGS. 3C and 3D, the distance t between the center axes X1 and X2 exceeds 0 (that is, The detection range of both the detection coils L1 and L2 is within the range of the outer diameter of the detection coil L (so that the detection ranges of the detection coils L1 and L2 in the moving direction of the detection unit 110 are not equal). It is set to such a size that it can be positioned inside (that is, the detected portion 110 can be detected simultaneously by both detection coils L1, L2).

  As described above, the detection coil L can be arranged in the vicinity of the moving region of the detected part 110 by arranging the moving body 100 in the insertion part 31a of the coil holding part 31 provided with the detection coil L. At this time, if the coil holding part 31 is arranged so that the central axis of the insertion part 31a coincides with the central axis of the moving body 100 (that is, the central axis M of the detected part 110), the moving body 100 and the detected part 110 has a circular cross section in a plane orthogonal to the central axis (perfect circular shape), and therefore the detection sensitivity may vary even when the mobile body 100 rotates about the central axis. And stable detection results can be obtained.

  Incidentally, a rod-shaped core (for example, a ferrite core) 4 made of a magnetic material is disposed inside each detection coil L. The outer shape of the core 4 may be a round bar shape or a square bar shape, and is not particularly limited. By providing such a core 4, if the number of turns of the detection coil L is the same, the magnetic flux can be made larger than that of the air-core detection coil L, so that the amount of change in the impedance of the detection coil L can be increased, The accuracy can be improved.

  As shown in FIG. 4, the position sensor of the present embodiment is used in a state of being connected to the arithmetic processing unit 6 including an electronic control unit of the vehicle. A plurality of connection terminals 5 for electrically connecting the detection circuit unit 2 and the arithmetic processing unit 6 housed in the unit, and a plurality of coils for electrically connecting the detection circuit unit 2 and the detection coil L A terminal (not shown) is inserted.

  Here, as shown in FIGS. 2A to 2C and FIG. 4, the connection terminal 5 is a power supply terminal for applying the power supply voltage Vcc to the detection circuit unit 2, and the detection circuit unit 2 is connected to the ground GND. It is used as either a grounding terminal for output and an output terminal for outputting the detection signal Vout of the detection circuit unit 2. That is, the position sensor of the present embodiment includes three connection terminals 5. Such a connection terminal 5 is bent from, for example, a long metal plate, and one end side protrudes into the housing portion of the trunk portion 30 and the other end side is upward from the upper surface of the trunk portion 30. The main body 3 is inserted into the protruding shape. Then, one end side of the connection terminal 5 is electrically and mechanically connected to the detection circuit unit 2 by soldering or the like in the housing portion of the trunk portion 30.

  On the other hand, the coil terminal is used to pass a current through the detection coil L, and two coil terminals are used for one detection coil L. Since the position sensor of this embodiment includes two detection coils L, each detection coil L includes two coil terminals, two in total. Such a coil terminal is bent from a long metal plate similarly to the connection terminal 5, and one end side protrudes into the housing portion of the body portion 30 and the other end side is a coil holding portion 31. It is inserted into the main body 3 in a form arranged inside. The one end side of the coil terminal is electrically and mechanically connected to the detection circuit portion 2 by soldering or the like in the housing portion of the body portion 30, and the end portion of the detection coil L is electrically connected to the other end side of the coil terminal. And mechanically connected.

  By the way, as shown in FIG.2 (c), the other end side of each of the three connection terminals 5 protrudes upward from the upper surface of the trunk | drum 30. As shown in FIG. Accordingly, a connector that can be coupled to a connector of a connection line (not shown) used for connection between the detection circuit unit 2 and the arithmetic processing unit 6 (hereinafter referred to as “mating connector”) should be configured in the main body unit 3. On the upper surface of the body portion 30, a rectangular tubular connector portion 32 that integrally surrounds the three connection terminals 5 is integrally projected. On the front surface side of the connector portion 32, a fitting convex portion 32a is provided so as to project integrally with a fitting concave portion (not shown) provided in the mating connector to prevent the mating connector from being pulled out. . In addition, guide protrusions 32b formed in a rectangular parallelepiped shape with the vertical direction as the longitudinal direction are integrally provided on the rear surface side of the connector part 32 and on both side surfaces in the width direction (left and right direction in FIG. 2A). Has been. Such a guide protrusion 32b is concavo-convexly engaged with a groove (not shown) of the mating connector to guide the mating connector to a fixed position with respect to the connector 32, so that the connection terminal 5 is connected to the mating connector. It is used to easily connect to a connection part (not shown). In addition, what is necessary is just to change suitably the shape of such a connector part 32 according to the shape of the other party connector, and is not the meaning limited to said example.

  Further, as shown in FIGS. 2A to 2D, on the upper end side of the outer peripheral surface of the trunk portion 30, a position sensor is attached to the body 500 of the hydraulic control device of the automatic transmission as described above. The attachment part 33 is provided integrally. The attachment portion 33 is formed in a rhombus shape in a plan view with a width dimension (a dimension in the vertical direction in FIG. 2C) becoming smaller (tapered) as it goes forward or backward with respect to the body portion 30, A screw insertion hole 33a having a shape penetrating the attachment portion 33 in the thickness direction (vertical direction) is provided in each of the front end portion and the rear end portion. Therefore, the main body 3 is formed, for example, in the mounting hole 520 provided in the body 500 of the hydraulic control device, in the mounting hole 520 having substantially the same size as the outer shapes of the body 30 and the coil holding part 31. In a state in which 31 is arranged, it is attached and fixed to the body of the hydraulic control device by a fixing screw (not shown) inserted through the screw insertion hole 33a of the attachment portion 33. As shown in FIG. 5, when the mounting hole 520 is provided so as to communicate with the flow path 510 of the body 500 of the hydraulic control device, the driving oil 600 flowing through the flow path 510 may ooze out from the mounting hole 520. However, this can be prevented by providing an O-ring in the groove 30a of the body 30.

  The detection circuit unit 2 is formed by mounting various electronic components constituting the determination unit 20 on a rectangular printed board (not shown) formed using, for example, a copper clad laminate. Thus, it has a circuit configuration as shown in FIG.

  As shown in FIG. 4, the determination unit 20 includes a capacitor C that is connected in parallel to the detection coil L and forms an LC resonance circuit (hereinafter simply referred to as “resonance circuit”) together with the detection coil L, and a semiconductor switching device such as a transistor. The switch SW which consists of an element, and the control part 20a are provided, and what is called a proximity switch (proximity sensor) with the detection coil L is comprised.

  The control unit 20a generates an high-frequency voltage having a frequency near the resonance frequency of the resonance circuit based on the power supply voltage Vcc supplied from the outside and supplies the high-frequency voltage to the resonance circuit, and oscillation of the resonance circuit And a signal processing circuit (not shown) for turning on / off the switch SW in accordance with a change in state. The signal processing circuit turns off the switch SW when the resonance circuit is oscillating, and turns off the switch SW when the detected portion 110 is located within the detection range of the detection coil L and the oscillation of the resonance circuit stops. Configured to turn on. Here, if the inductance of the detection coil L and the capacity of the capacitor C are set so that the resonance circuits have different resonance frequencies, the influence of fluctuations in the oscillation state of one resonance circuit is set. However, it is possible to prevent other resonance circuits from reaching (mutual interference), so that the detection accuracy can be improved. In the following description, the discriminating unit 20 is denoted by reference numerals 20A and 20B as necessary to distinguish the two discriminating units 20, and the switch SW is denoted by reference characters SW1, SW2 as necessary to distinguish the two switches SW. This is indicated by SW2.

  The detection circuit unit 2 includes a resistor Ra having one end connected to the connection terminal 5 serving as a power supply terminal, and a resistor Rb connected between the other end of the resistor Ra and the connection terminal 5 serving as a ground terminal. The connection points of the resistors Ra and Rb are connected to a connection terminal 5 serving as an output terminal. Further, the detection circuit unit 2 includes a resistor R1 connected between the connection point of the resistors Ra and Rb and the switch SW1, and a resistor R2 connected between the connection point of the resistors Ra and Rb and the switch SW2. I have. That is, the resistor Rb of the detection circuit unit 2 is connected in parallel with a series circuit including the resistor R1 and the switch SW1 of the determination unit 20A and a series circuit including the resistor R2 and the switch SW2 of the determination unit 20B. In this embodiment, the power supply voltage Vcc is 5 [V], the resistor Ra is 3.3 [kΩ], the resistor Rb is 13 [kΩ], the resistor R1 is 3.3 [kΩ], and the resistor R2 is 10 [kΩ]. ] Is set for each. However, the values of the power supply voltage Vcc and the resistors Ra, Rb, R1, and R2 are examples, and are not intended to be limited to the above numerical values.

  Next, the operation of the detection circuit unit 2 will be described with reference to FIGS. 1A to 1D, the arrangement of the detection coils L1 and L2 is different from that in FIGS. 3A to 3D in order to easily explain the operation. This also applies to FIGS. 5 to 9.

  First, as shown in FIG. 1 (a), the position of the moving body 100 is positioned within the detection range of the detection coils L1 and L2 with the detected portion 110 positioned in front of the coil holding portion 31. When the position is not (hereinafter referred to as “position A”), both the switches SW1 and SW2 are turned off. At this time, the potential of the detection signal Vout becomes a value obtained by dividing the power supply voltage Vcc by the resistor Ra and the resistor Rb, that is, about 3.99 [v].

  Thereafter, the moving body 100 moves backward from the position A, and the position of the moving body 100 is such that the detected portion 110 is located only within the detection range of the detection coil L1, as shown in FIG. When the position is reached (hereinafter referred to as “position B”), the switch SW1 is turned on and the switch SW2 is turned off. At this time, the potential of the detection signal Vout becomes a value obtained by dividing the power supply voltage Vcc by the resistors Rb and R1 and the resistor Ra connected in parallel, that is, about 2.22 [v].

  Thereafter, the moving body 100 moves backward from the position B, and the position of the moving body 100 is within the detection range of both the detection coils L1 and L2, as shown in FIG. When the position is reached (hereinafter referred to as “position C”), both the switches SW1 and SW2 are turned on. At this time, the potential of the detection signal Vout becomes a value obtained by dividing the power supply voltage Vcc by the resistors Rb, R1, R2 and the resistor Ra connected in parallel, that is, about 1.93 [V].

  After that, the moving body 100 moves backward from the position C, and the position of the moving body 100 is such that the detected part 110 is positioned only within the detection range of the detection coil L2 as shown in FIG. When the current position (hereinafter referred to as “position D”) is reached, the switch SW1 is turned off and the switch SW2 is turned on. At this time, the potential of the detection signal Vout becomes a value obtained by dividing the power supply voltage Vcc by the resistors Rb, R2 and the resistor Ra connected in parallel, that is, about 3.16 [V].

  The operations of the detection circuit unit 2 described above are summarized as shown in Table 1 below. In Table 1 below, “◯” indicates that the switch SW is in an on state, and “x” indicates that the switch SW is in an off state. This also applies to Tables 2 and 3 below.

  That is, the detection circuit unit 2 in the present embodiment is configured to output the detection signal Vout having a different potential for each combination of on / off of the switch SW, which is the determination result of the two determination units 20.

  Correspondingly, the calculation processing unit 6 is provided with the above-described position determination unit 60 that determines the position of the moving body 100 based on the potential of the detection signal Vout of the detection circuit unit 2. For example, if the potential of the detection signal Vout is about 1.93 [V], the moving body 100 is at the position C, and if the potential of the detection signal Vout is about 2.22 [V], the moving body 100 is at the position B. If it is 16 [V], it is determined that the moving body 100 is positioned at the position D, and if it is about 3.99 [V], it is determined that the moving body 100 is positioned at the position A. Such a position determination unit 60 is realized by software or the like provided in the arithmetic processing unit 6.

  According to the position sensor of the present embodiment described above, the detection coil L along the central axis X in the direction intersecting the moving direction of the detected portion 110 is placed in the moving direction near the moving region of the detected portion 110. Since a plurality of the coils are arranged in a line, the position of the moving body 100 can be detected depending on whether the impedance of the detection coil L has changed. Unlike the conventional example corresponding to the amount of insertion into L, it is not necessary to increase the number of turns of the detection coil L in order to improve the detection accuracy. As a result, the detection accuracy is reduced while reducing the manufacturing cost and reducing the size. Can be improved.

  In addition, the position sensor of the present embodiment can detect the position of the moving body 100 by arranging the detection coils L in the vicinity of the moving area of the detected portion 110 in the moving direction of the detected portion 110. When attaching the position sensor, unlike the conventional example (see FIG. 13), there is no need to insert the moving body 100 in the detection coil 200, so the moving body 100 is placed at a predetermined position with respect to the device (for example, a hydraulic control device). There is no need to insert the moving body 100 into the position sensor in advance, and the assembly order of the apparatus is flexible, so that the position sensor can be easily attached, and the completed apparatus has a position sensor. Can be retrofitted. In addition, since the position sensor of the present embodiment can detect the position of the moving body 100 in a non-contact manner, it is superior in durability, strong against vibration, and sealed against liquids such as oil, compared to a position sensor that requires mechanical connection. There is an advantage that the structure can be easily realized.

  Further, as shown in FIGS. 3A and 3B, adjacent detection coils L1 and L2 are arranged adjacent to each other in a plane orthogonal to the moving direction of the detected portion 110, so that they are adjacent to each other. Since the detection coils L1 and L2 can be prevented from magnetically interfering with each other, the detection accuracy can be improved. Further, by arranging the adjacent detection coils L1 and L2 in a shape that does not overlap in a plane orthogonal to the moving direction of the detected part 110, these adjacent ones as shown in FIGS. 3 (c) and 3 (d). The detection coils L1 and L2 can be arranged so that the distance t between the central axes X1 and X2 is greater than 0 and less than or equal to the outer diameter of the detection coil L. The interval between the coils L can be set to be equal to or smaller than the outer diameter dimension of the detection coil L. That is, when these detection coils L are arranged along the moving direction, the distance between the detection coils L must be larger than the outer diameter of the detection coils L, but the adjacent detection coils L are detected by the detected portion 110. By arranging them in a shape that does not overlap in a plane orthogonal to the moving direction, the distance between the detection coils L can be set to be equal to or smaller than the outer diameter dimension of the detection coils L. As a result, the position of the moving body 100 can be further increased. It will be possible to detect with fine detail.

  On the other hand, since the position determination unit 60 combines the determination results of the plurality of determination units 20, the position determination unit 60 moves compared to the case where the position of the moving body 100 is determined using only one of the determination results of the plurality of determination units 20. The position of the body 100 can be detected more finely.

  In addition, since only one signal line is required to transmit the detection signal Vout of the detection circuit unit 2 to the arithmetic processing unit 6 provided with the position determination unit 60, the detection circuit unit 2 includes a plurality of determination units 20. Unlike the case of individually outputting the discrimination results as the detection signal Vout, it is not necessary to provide the arithmetic processing unit 6 with the same number of ports as the number of the discriminating units 20 to connect the signal lines. That is, the configuration of the arithmetic processing unit 6 provided with the position determining unit 60 can be simplified, and the manufacturing cost can be reduced. In addition, since the determination unit 20 of the detection circuit unit 2 is configured by a proximity switch, and such a proximity switch is relatively inexpensive, the manufacturing cost can be reduced.

  Incidentally, since the driving oil 600 is injected into the flow path 510 of the hydraulic control apparatus as described above in a high pressure state, the body 500 of the hydraulic control apparatus is often formed of a metal material. If the detection coil L is disposed in the mounting hole 520 as shown in FIG. 5 when the metal is formed of a metal material, the detection accuracy may be deteriorated due to the influence of the metal material constituting the body 500.

  As shown in FIG. 5, a shield member 7 for magnetic shielding may be provided in the coil holding portion 31 to solve this problem. The shield member 7 is formed of, for example, a magnetic metal such as iron, or a magnetic material, and has a plate shape that can cover the entire detection coil L in the direction along the moving direction of the detected portion 110. Is formed.

  Such a shield member 7 includes other detection coils L1 and L2 at both ends in the moving direction of the detected portion 110 among the plurality of detection coils L1 and L2, and other detection coils L2 (in the detection coil L1, the detection coil L2). For the detection coil L2, the side opposite the detection coil L1 (the rear side for the detection coil L1 and the front side for the detection coil L2) is the opposite side (the front side for the detection coil L1). The coil holding portion 31 is provided in such a manner as to be located on the side, the rear surface side of the detection coil L2. By arranging both of the two detection coils L between the shield members 7 in this way, the detection coil L is formed of a metal member (in the example shown in FIG. 5, formed of a metal material) around the moving body 100. The influence of the body 500) of the hydraulic control device can be prevented, and the detection accuracy can be prevented from deteriorating. Incidentally, the shield member 7 may be provided between the adjacent detection coils L. In this case, since the adjacent detection coils L can be prevented from magnetically interfering with each other, the detection accuracy can be improved. Moreover, the shape of the shield member 7 is an example, and is not intended to be limited to the above shape.

  Note that the position sensor of this embodiment is merely an example, and may be modified to the extent that it does not depart from the spirit of the present invention. For example, the position determination unit 60 may be provided in the main body unit 3 together with the detection circuit unit 2 instead of using the vehicle-side arithmetic processing unit 6. Further, unlike the example shown in FIG. 3, the plurality of detection coils L are overlapped in the moving direction of the detected part 110 as shown in FIGS. 1 (a) and 1 (b). They may be arranged at predetermined intervals. Further, the insertion part 31a of the coil holding part 31 is not limited to the semicircular shape, and the point is that the moving body 100 can be arranged in the insertion part 31a from the direction orthogonal to the moving direction. Anything is acceptable. Further, the determination unit 20 may turn on the switch SW when the resonance circuit is oscillating, and may turn off the switch SW when the oscillation stops, and may be set as appropriate according to the situation.

  By the way, as shown in FIG. 1, the above-described detected portion 110 is a disc-like one protruding from the outer peripheral surface of the moving body 100, but for example, as shown in FIG. A part of the moving body 100 may be formed to have an outer diameter smaller than the outer diameter of the moving body 100 by recessing the outer peripheral surface. In short, if the cross-sectional area in the plane orthogonal to the moving direction of the moving body 100 is different from that of the moving body 100, the impedance of the detection coil L can be changed, and therefore, it can be used as the detected part 110.

(Embodiment 2)
In the position sensor of the present embodiment, the configuration of the coil holding portion 31 is different from that of the first embodiment, and the other configurations are the same as those of the first embodiment. Therefore, the description and illustration of the same configuration are omitted.

  As shown in FIG. 7, the coil holding unit 31 in the present embodiment is such that the detected unit 110 located within the detection range of the detection coil L2 faces the other detection coil (that is, the detection coil L1) in the detection coil L2. A stopper portion 31b is provided that restricts movement to the opposite side (that is, the rear surface side) from the side to be touched by contacting the detected portion 110. The stopper portion 31b is provided at the opening edge of the insertion portion 31a on the rear surface side of the coil holding portion 31 so as to protrude into the insertion portion 31a.

  Therefore, in the position sensor of the present embodiment, when the moving body 100 tries to move backward from the position D shown in FIG. 1D, the rear surface of the detected portion 110 collides with the front surface of the stopper portion 31b. Thus, since the moving body 100 cannot move rearward, the moving body 100 is configured such that the detected portion 110 as shown in FIG. 8 is positioned behind the coil holding portion 31 and any of the detection ranges of the detection coils L1 and L2. It is impossible to move to a position (hereinafter referred to as “position E”) that is not located inside. Needless to say, when the stopper portion 31b is provided, the original operation of the moving body 100 (the opening / closing operation of the valve in the case of a linear solenoid valve) is not hindered.

  That is, in the position sensor of the first embodiment, when the moving body 100 moves rearward from the position D shown in FIG. 6D and reaches the position E shown in FIG. 8, both the switches SW1 and SW2 are turned on. Since it is turned off, the potential of the detection signal Vout becomes the value obtained by dividing the power supply voltage Vcc by the resistor Ra and the resistor Rb at the position E, as in the position A. Therefore, the positions A and E and the positions BD Although the position A and the position E could not be distinguished from each other, the moving body 100 does not move to the position E in the position sensor of the present embodiment. , Positions A to D correspond one-on-one.

  Therefore, according to the position sensor of the present embodiment described above, the same effect as in the first embodiment can be obtained, and the detected portion 110 is not located within the detection range of any detection coil L. However, since the position of the moving body 100 can be specified, the position of the moving body 100 can be prevented from being confused (that is, the position A and the position E can be distinguished), and the position of the moving body 100 can be accurately detected. it can.

  In addition to the example shown in FIG. 7, as the stopper portion 31b, the detected portion 110 positioned within the detection range of the detection coil L1 faces the other detection coil (that is, the detection coil L2) in the detection coil L1. The movement to the opposite side (ie, the front side) from the moving side is restricted by contacting the detected portion 110 (that is, the position of the detected portion 110 is detected at positions B to E excluding the position A). It may be possible). In this case, the stopper part 31b is provided in the shape which protrudes in the insertion part 31a in the opening edge part of the insertion part 31a in the front side of the coil holding | maintenance part 31. FIG.

  In short, the stopper portion 31b is configured such that the detected portion 110 located within the detection range of one of the detection coils L at both ends in the moving direction among the plurality of detection coils L is the other detection coil L in the detection coil L. As long as the movement to the opposite side to the opposite side is restricted by coming into contact with the detected part 110, it is sufficient.

  However, if the position determination unit 60 is configured to be able to distinguish between the position A and the position E by software, it is not necessary to provide the stopper portion 31b as in the present embodiment. For example, when the position determination unit 60 stores the history of the potential of the detection signal Vout and the potential of the detection signal Vout changes to become the value at the positions A and E, the detection signal Vout immediately before (before the change). If the potential of the detection signal Vout is at the position D, it is determined that the moving body 100 is at the position E. What is necessary is just to comprise so that it may discriminate | determine. Further, when the position of the moving body 100 is determined in the first place, even when it is not necessary to distinguish the positions A and E, it is not necessary to provide the stopper portion 31b. These points are the same in the third embodiment described later.

(Embodiment 3)
In the position sensor of the present embodiment, the configuration of the detection coil L is different from that of the first embodiment, and other configurations are the same as those of the first embodiment. Therefore, the description and illustration of the same configuration are omitted.

  As shown in FIG. 9, the detection coil L2 in the present embodiment has a detection range on the side opposite to the side facing the other detection coil (that is, the detection coil L1) in the detection coil L2 (that is, the rear side). The outer diameter dimension is set so as to reach the boundary S of the movement range of the detected part 110.

  That is, in the position sensor of this embodiment, even if the moving body 100 moves backward from the position D shown in FIG. 1D, the detected part 110 does not go out of the detection range of the detection coil L2. Since the detected part 110 is always detected by the detection coil L2, the moving body 100 is not positioned at the position E. As a result, the positions A to D are a pair with respect to the potential of the detection signal Vout. It comes to correspond with one.

  Therefore, according to the position sensor of the present embodiment, the position of the moving body 100 can be prevented from being confused and the position of the moving body 100 can be accurately detected, as in the second embodiment.

  By the way, in the present embodiment, the detection portion 110 of the detection coil L2 is detected on the opposite side (that is, the rear surface side) of the detection coil L2 from the side facing the other detection coil (that is, the detection coil L1). In contrast, the detection coil L1 is configured such that the detection range of the detection coil L1 is opposite to the other detection coil (that is, the detection coil L2) in the detection coil L1. You may comprise in the form which reaches the boundary (not shown) of the movement range of the to-be-detected part 110 in the other side (namely, front side).

  In this case, even if the moving body 100 moves forward from the position B shown in FIG. 1B, the detected part 110 does not go out of the detection range of the detection coil L1. Since it is detected by the detection coil L1, the moving body 100 is not positioned at the position A, and as a result, the positions B to E correspond one-to-one with the potential of the detection signal Vout. Therefore, the position of the moving body 100 can be prevented from being confused, and the position of the moving body 100 can be accurately detected.

  Even in the case where three or more detection coils L are provided, one of the detection coils L at both ends in the moving direction among the plurality of detection coils L, and the detection range of the detection coil L is different. If the configuration extends to the boundary of the movement range of the detected portion 110 on the side opposite to the side facing the detection coil L, the same effect as described above can be obtained.

(Embodiment 4)
As shown in FIG. 10, the position sensor of the present embodiment is different from the first to third embodiments in the configuration of the coil holding unit 31 and the detection circuit unit 2, and the other configurations are the same as those in the first embodiment. Therefore, description and illustration of the same configuration will be omitted.

  In the coil holding part 31 in the present embodiment, three detection coils L are arranged at equal intervals so as to be separated from each other in the moving direction of the detected part 110. In the following description, in order to distinguish the detection coil L, the detection coil L at the right end in FIG. 10 is denoted by reference numeral L1, and the central detection coil L in FIG. 10 is denoted by reference numeral L2, as necessary. The left detection coil L is represented by the symbol L3.

  Further, the outer diameter of each detection coil L is such that the distance between the detection coils L1 and L2 can position the detected portion 110 within the detection range of both the detection coils L1 and L2 (that is, by both detection coils L1 and L2). The distance between the detection coils L2 and L3 can be positioned within the detection range of both the detection coils L2 and L3 (that is, both detections can be performed). The detected portion 110 can be detected simultaneously by the coils L2 and L3. Although not shown in FIG. 10, the coil holding portion 31 is provided with a stopper portion 31b similar to that described in the second embodiment.

  The detection circuit unit 2 in the present embodiment is different from the first embodiment in that it includes a total of three determination units 20 in a form corresponding to each of the three detection coils L. In the following description, the discriminating unit 20 is denoted by reference numerals 20A, 20B, and 20C as necessary to distinguish the three discriminating units 20, and the switch SW is denoted by reference numeral as necessary to distinguish the three switches SW. It is represented by SW1, SW2 and SW3.

  The detection circuit unit 2 according to the present embodiment is different from the first embodiment in that the resistor R3 is connected between the connection point of the resistors Ra and Rb and the switch SW3. That is, the resistor Rb of the detection circuit unit 2 in this embodiment includes a series circuit including the resistor R1 and the switch SW1 of the determination unit 20A, a series circuit including the resistor R2 and the switch SW2 of the determination unit 20B, the resistor R3, and the determination. The series circuit including the switch SW3 of the unit 20C is connected in parallel.

  Next, the operation of the detection circuit unit 2 in this embodiment will be described. First, the position of the moving body 100 is a position where the detected part 110 is located in front of the coil holding part 31 and is not located in any of the detection ranges of the detection coils L1 to L3 (hereinafter referred to as “position a”). All the switches SW1 to SW3 are turned off.

  Thereafter, the moving body 100 moves rearward from the position a, and the position of the moving body 100 is a position where the detected part 110 is located only within the detection range of the detection coil L1 (hereinafter referred to as “position b”). Only the switch SW1 is turned on.

  After that, the moving body 100 moves backward from the position b, and the position of the moving body 100 is the position where the detected part 110 is located within the detection range of both the detection coils L1 and L2 (hereinafter, “ In the case of “position c”), both the switches SW1 and SW2 are turned on.

  After that, the moving body 100 moves backward from the position c, and the position of the moving body 100 is the position where the detected part 110 is located within the detection range of all the detection coils L (hereinafter referred to as “position d”). All the switches SW1 to SW3 are turned on.

  After that, the moving body 100 moves backward from the position d, and the position of the moving body 100 is the position where the detected part 110 is located within the detection range of both the detection coils L2 and L3 (hereinafter, “ In this case, both the switches SW2 and SW3 are turned on.

  Thereafter, the moving body 100 moves rearward from the position e, and the position of the moving body 100 is a position where the detected part 110 is located only within the detection range of the detection coil L3 (hereinafter, “position f”). In this case, only the switch SW3 is turned on.

  When the moving body 100 attempts to move backward from the position f, the rear surface of the detected part 110 abuts against the front surface of the stopper part 31b, and therefore the moving body 100 cannot move backward from the position f. Therefore, the position of the moving body 100 does not become a position where the detected part 110 is located behind the coil holding part 31 and is not located in any of the detection ranges of the detection coils L1 to L3.

  The operations of the detection circuit unit 2 described above are summarized as shown in Table 2 below.

  The potential of the detection signal Vout is a value obtained by dividing the power supply voltage Vcc by the resistor Ra and the resistor Rb at the position a, and at the position b by the resistors Rb, R1 and the resistor Ra in which the power supply voltage Vcc is connected in parallel. At the position c, a value obtained by dividing the power supply voltage Vcc with the resistors Rb, R1, R2 and the resistor Ra connected in parallel at the position c, and at the position d, the resistors Rb, R1 to R1 connected in parallel with the power supply voltage Vcc. The value divided by R3 and the resistor Ra, the value divided by the resistors Rb, R2, R3 and the resistor Ra connected in parallel to the power supply voltage Vcc at the position e, and the power supply voltage Vcc connected in parallel at the position f The voltage is divided by the resistors Rb and R3 and the resistor Ra.

  Here, the resistance values of the resistors Ra, Rb, R1, R2, and R3 are different from each other in the potentials of the detection signals Vout at the positions a to f, and can be sufficiently distinguished from each other. It is set. Accordingly, the position determination unit 60 is configured to determine which of the positions a to f the position of the moving body 100 is based on the potential of the detection signal Vout.

  According to the position sensor of the present embodiment described above, the same effect as in the first to third embodiments is obtained, and the number of detection coils L is increased as compared with the first to third embodiments. Can be determined more precisely.

  By the way, when it is going to discriminate | determine the position of the mobile body 100 by the combination of the discrimination | determination result of the some discrimination | determination part 20, the structure of the to-be-detected part 110 and the structure of the detection coil L are important. For example, in the example shown in FIG. 10, three detection coils L are used, and eight combinations are conceivable. However, only six combinations can be obtained due to the configuration of the detected section 110.

  Thus, when three detection coils L are used, it is conceivable to use the detected part 110 as shown in FIG. 12 in order to be able to use all eight combinations. The detected portion 110 includes a disc-shaped first detected portion 110a provided on the rear end side of the moving body 100, and a disc-like shape provided on the front end side of the moving body 100 relative to the first detected portion 110a. It is comprised with the 2nd to-be-detected part 110b. The length of the first detected portion 110a in the central axis direction is set to a value that is located only in one detection range of the three detection coils L and cannot be simultaneously located in the detection ranges of the plurality of detection coils L. The length of the second detected portion 110b in the central axis direction is set to a value that can be simultaneously positioned within all the detection ranges of the three detection coils L.

  In addition, the first detected unit 110a and the second detected unit 110b are configured such that when the first detected unit 110a is positioned within the detection range of the detection coil L3, the second detected unit 110b detects the detection range of the detection coil L1. They are arranged with a distance (generally the same distance as the length of the detection coil L in the central axis direction). The first detected part 110a and the second detected part 110b both have the same outer diameter, and the center axis of each of the detected parts 110a and 110b coincides with the center axis of the moving body 100, so that the moving body 100 protrudes.

  Hereinafter, the operation of the detection circuit unit 2 when the detected unit 110 as shown in FIG. 12 is used will be described. First, as shown in FIG. 12, the position of the moving body 100 is a position where the detected part 110 is located in front of the coil holding part 31 and is not located in any of the detection ranges of the detection coils L1 to L3. (Hereinafter referred to as “position a”), all the switches SW are turned off.

  Thereafter, the moving body 100 moves rearward from the position a, and the position of the moving body 100 is a position where the first detected part 110a is located only within the detection range of the detection coil L1 (hereinafter referred to as “position b”). ”), Only the switch SW1 is turned on.

  Thereafter, the moving body 100 moves rearward from the position b, and the position of the moving body 100 is a position where the first detected part 110a is located only within the detection range of the detection coil L2 (hereinafter referred to as “position”). c ”) (in this case, the second detected unit 110b detects the detection coil L1 when the first detected unit 110a is positioned only within the detection range of the detection coil L3. Since the movable body 100 is provided so as to be positioned within the range, only the switch SW2 is turned on when the second detected portion 110b is not yet positioned within the detection range of the detection coil L1.

  Thereafter, the moving body 100 moves rearward from the position c, and the position of the moving body 100 is a position where the first detected part 110a is located only within the detection range of the detection coil L3 (hereinafter referred to as “position”). d ”), the second detected part 110b is also located within the detection range of the detection coil L1, so that both the switches SW1 and SW3 are turned on.

  Furthermore, after that, the moving body 100 moves backward from the position d, and the position of the moving body 100 is not positioned within the detection range of any of the detection coils L by the first detected part 110a. When the part 110b is in a position (hereinafter referred to as “position e”) within the detection range of both the detection coils L1 and L2, both the switches SW1 and SW2 are turned on.

  After that, the moving body 100 moves backward from the position e, and the position of the moving body 100 is the position where the second detected part 110b is located within the detection range of all the detection coils L (hereinafter, “ All the switches SW are turned on.

  Thereafter, the moving body 100 moves rearward from the position f, and the position of the moving body 100 is a position where the second detected part 110b is located within the detection range of both the detection coils L2 and L3 (hereinafter referred to as the position of the moving body 100). , Referred to as “position g”), both the switches SW2 and SW3 are turned on.

  Thereafter, the moving body 100 moves backward from the position g, and the position of the moving body 100 is a position where the second detected part 110b is located only within the detection range of the detection coil L3 (hereinafter referred to as “position”). h ”), only the switch SW3 is turned on.

  When the moving body 100 tries to move backward from the position h, the rear surface of the first detected part 110a abuts against the front surface of the stopper part 31b. Since it cannot move, the position of the moving body 100 does not become a position where the second detected part 110b is located behind the coil holding part 31 and is not located in any detection range of the detection coils L1 to L3. .

  The operations of the detection circuit unit 2 described above are summarized as shown in Table 3 below.

  The potential of the detection signal Vout is a value obtained by dividing the power supply voltage Vcc by the resistor Ra and the resistor Rb at the position a, and at the position b by the resistors Rb, R1 and the resistor Ra in which the power supply voltage Vcc is connected in parallel. At the position c, a value obtained by dividing the power supply voltage Vcc by the resistors Rb, R2 and the resistor Ra connected in parallel at the position c, and at the position d, the resistors Rb, R1, R3 connected by the power supply voltage Vcc in parallel A value divided by the resistor Ra, a value obtained by dividing the power supply voltage Vcc by the resistors Rb, R1, R2 and the resistor Ra connected in parallel at the position e, and a resistor obtained by dividing the power supply voltage Vcc in the position f A value divided by Rb, R1 to R3 and resistor Ra, a value obtained by dividing power supply voltage Vcc by resistors Rb, R2, R3 and resistor Ra connected in parallel at position g, and a power supply voltage V at position h. c parallel connected resistors Rb, the dividing value in the R3 and the resistor Ra.

  Here, the resistance values of the resistors Ra, Rb, R1, R2, and R3 are different from each other in the potentials of the detection signals Vout at the positions a to h, and can be sufficiently distinguished from each other. It is set. Accordingly, the position determination unit 60 is configured to determine which of the positions a to h the position of the moving body 100 is based on the potential of the detection signal Vout.

  In this way, since the positions of different moving bodies 100 can be associated with all combinations of the discrimination results of the three discriminating units 20, as shown in FIG. 10, only 6 of the 8 combinations are moving bodies. Compared to the case where the position of the moving body 100 is not used for the determination of the position of 100, the position of the moving body 100 can be determined more precisely.

The number of detection coils L used in the position sensor of the present invention is not limited to three as in the present embodiment or two as in the first to third embodiments, and may be four or more. Even in such a case, the number of the determination units 20 is provided in a form corresponding to each of the plurality of detection coils L. In addition, the shape or arrangement (layout) of the detected unit 110 and the detection coil L may be such that the position of the moving body 100 corresponds to each combination of the determination results of the plurality of determination units 20. This is preferable from the viewpoint of finely determining the position of the moving body 100. In this way, for example, when the number of the determination units 20 is m (where m is an integer of 2 or more), the moving body 100 It is possible to determine which position of 2 ^m is located.

2 is a schematic diagram of a position sensor according to Embodiment 1. FIG. The detection part of the position sensor in the same as above is shown, (a) is a side view, (b) is a rear view, (c) is a top view, and (d) is a bottom view. The principal part of the detection part of a position sensor in the same as the above is shown, (a) is a schematic sectional view taken along line AA in FIG. 2 (d), and (b) is a schematic sectional view taken along line BB in FIG. 2 (d). (C) is a schematic sectional drawing in the CC line of FIG.2 (b), (d) is a schematic sectional drawing in the DD line of FIG.2 (b). It is the schematic of the circuit of the position sensor in the same as the above. It is the schematic which shows the principal part of the other example of the position sensor in the same as the above. It is the schematic which shows the principal part of the further another example of the position sensor in the same as the above. FIG. 5 is a schematic diagram illustrating a main part of a position sensor according to a second embodiment. It is the schematic of the position sensor of a comparative example. It is the schematic which shows the principal part of the position sensor of Embodiment 3. FIG. 6 is a schematic diagram illustrating a main part of a position sensor according to a fourth embodiment. It is the schematic of the circuit of the position sensor in the same as the above. It is the schematic which shows the other example of the principal part of the position sensor in the same as the above. It is the schematic of the conventional position sensor.

Explanation of symbols

L, L1, L2 Detection coil X, X1, X2 Central axis 2 Detection circuit unit 4 Core 5 Shield member 6 Position determination unit 20 Determination unit 100 Moving object 110 Detected unit M Central axis

Claims (9)

A position sensor that is provided on a moving body that moves along a predetermined path and detects the position of a metal detected part that is moved together with the moving body,
A plurality of detection coils arranged in the vicinity of the movement region of the detected part in a form along the central axis in a direction intersecting the moving direction of the detected part and aligned with the moving direction;
And a detection circuit unit having a plurality of determination units that are provided corresponding to each of the plurality of detection coils and determine whether or not the detection target unit is located within the detection range of the detection coil. Position sensor to perform.   The position sensor according to claim 1, further comprising a position determination unit that determines a position of the moving body based on a combination of determination results of the plurality of determination units.   The detection circuit unit is configured to output a detection signal having a different potential according to a combination of the determination results of the plurality of determination units, and the position determination unit is configured to detect the position of the moving object based on the detection signal potential of the detection circuit unit. The position sensor according to claim 2, wherein the position sensor is configured to discriminate.   The detected portion located within the detection range of one of the detection coils at both ends in the moving direction among the plurality of detection coils moves to the side opposite to the side facing the other detection coil in the detection coil. The position sensor according to any one of claims 1 to 3, further comprising a stopper portion that regulates the contact portion by contacting the portion to be detected.   One of the detection coils at both ends in the movement direction among the plurality of detection coils has a detection range at the boundary of the movement range of the detected part on the opposite side of the detection coil from the side facing the other detection coil. The position sensor according to any one of claims 1 to 3, wherein the position sensor is configured in a range.   2. A shield member for a magnetic shield is provided on a side opposite to the side facing the other detection coil in each of the detection coils at both ends in the moving direction among the plurality of detection coils. The position sensor according to any one of?   The position sensor according to claim 1, wherein at least adjacent detection coils are arranged so as not to overlap in a plane orthogonal to the moving direction.   The said adjacent detection coil is comprised so that it may have the same outer diameter, and it is arrange | positioned so that the distance between center axes may become the value below 0 and the said outer diameter. Position sensor.   The position sensor according to claim 1, wherein a core made of a magnetic material is disposed inside the detection coil.

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