JP5873698B2 - Non-contact switch - Google Patents

Description

  The present invention relates to a non-contact switch that detects the position of an object to be detected made of a magnetic material by changing a bias magnetic field.

  For example, a contact point mechanical switch is known as a position detection switch for detecting a neutral position and a back position of an automobile transmission. However, this mechanical switch has a heavy operation feeling and has a limited number of times of durability. There are problems such as.

  Therefore, it is conceivable to use a non-contact non-contact switch that detects the position of an object to be detected made of a magnetic material by changing a bias magnetic field. Patent Document 1 discloses a rotation detection device that detects the rotation of a rotating body in a non-contact manner by applying the Hall effect.

  As a method of detecting an object to be detected by a non-contact switch, a semiconductor magnetic element such as a Hall element that detects a Hall voltage or a magnetoresistive element that detects a change in resistance is arranged in a bias magnetic field generated by a fixed bias magnet. There is a method in which a change produced in a bias magnetic field due to the approach of an object to be detected is detected by a semiconductor magnetic element. As an example, FIG. 12 shows a detection method using a back bias magnet system.

  That is, FIG. 12 is a diagram for explaining a detection method by a back bias magnet method of a non-contact switch. A magnetic bias is applied to the Hall element 103 which is a semiconductor magnetic element by a bias magnet 104 attached to the back surface thereof. Yes. Then, a change in magnetic flux density caused by the detected object 112, which is a magnetic body, moving from the solid line position to the chain line position in the direction of the arrow and approaching the Hall element 103 is detected by the Hall element 103, and the detected magnetic flux density is set. When the threshold value exceeds (or falls below), the non-contact switch is switched from OFF to ON (or from ON to OFF).

JP-A-6-082465

  However, when the back bias magnet system as shown in FIG. 12 is adopted as the detection method, the bias magnet 104 is set on the back surface of the Hall element 103, so that the object 112 to be detected is shown as a solid line in FIG. Even if it is not near 103, the magnetic flux density applied to the Hall element 103 becomes relatively high.

  Further, even when the detected object 112 approaches the Hall element 103 as indicated by a chain line in FIG. 12, it is necessary to keep the bias magnet 104 and the detected object 112 away from each other by the thickness distance b of the Hall element 103. Therefore, the magnetic flux density applied to the detected object 112 is reduced, and as a result, the magnetic flux density applied to the Hall element 103 is also relatively reduced.

  From the above, the change in the magnetic flux density applied to the Hall element 103 when the detection object 112 approaches or separates from the Hall element 103 is small, and the position variation between the Hall element 103 and the bias magnet 104, temperature drift, Hall Considering variations in the distance between the element 103, the bias magnet 104, and the detected object 112, it is difficult to set a magnetic flux density threshold for switching the non-contact switch.

  In order to solve the above problem, a configuration is possible in which a recess 104a is formed on the end face of the bias magnet 104 and the hall element 103 is accommodated in the recess 104a as shown in FIG. As a result, there is a problem that the layout of the Hall element 103 becomes difficult.

  The present invention has been made in view of the above problems, and an object thereof is to provide a non-contact switch in which a threshold for switching can be easily set.

In order to achieve the above object, a first aspect of the present invention is directed to a bias magnet that generates a bias magnetic field and a bias magnetic field that accompanies the approach of an object to be detected that is disposed in the bias magnetic field generated by the bias magnet and is made of a magnetic material. In a non-contact switch that includes a semiconductor magnetic element that detects a change in the position and a holding member that holds the bias magnet and detects the position of the object to be detected, the semiconductor magnetic element is separated from the bias magnet in the holding member. Forming an element mounting portion to hold , forming a concave portion on the front surface of the bias magnet facing the semiconductor element, disposing the element mounting portion of the holding member in the concave portion, and The inner wall surface of the recess is a tapered surface, and an area having the same magnetic flux density is distributed in parallel to the front surface of the bias magnet .

According to a second aspect of the present invention, in the first aspect of the present invention, the holding member holds a substrate to which the semiconductor magnetic element is electrically connected, and an electric signal generated by the substrate is externally connected to the holding member. A locking portion for locking a terminal base having a terminal that outputs to the terminal is formed.

According to a third aspect of the invention, in the first or second aspect of the invention, the bias magnet is divided into a plurality of parts and a magnetic material is sandwiched between them.

The invention according to claim 4 is the invention according to any one of claims 1 to 3 , wherein the semiconductor magnetic element is a Hall element.

  According to the first aspect of the present invention, since the semiconductor magnetic element is held away from the bias magnet by the element mounting portion of the holding member so as to ensure a certain distance between them, the detected object approaches. In this state, the magnetic flux density of the bias magnetic field applied to the semiconductor magnetic element can be reduced. For this reason, the difference in the magnetic flux density applied to the semiconductor magnetic element when the object to be detected is separated and approached becomes significant, and the threshold value of the magnetic flux density for switching the non-contact switch can be easily set. it can.

Further, since the inner wall surface of the recess formed on the front surface of the bias magnet facing the semiconductor magnetic element is a tapered surface, an area having the same magnetic flux density is distributed in parallel to the front surface of the bias magnet. For this reason, even if the position of the semiconductor magnetic element with respect to the bias magnet varies slightly in the radial direction (XY axis direction when the longitudinal axis direction of the non-contact switch is the Z axis), the magnetic field component does not change greatly, and the semiconductor magnetic element is highly mounted. Since accuracy is not required, the assembling property of the semiconductor magnetic element is improved.

Furthermore, the element attaching portion of the holding member for the disposed concave portion of the bias magnet, as compared with conventional, the thickness of the distance amount corresponding object to be detected in the semiconductor magnetic element can be made closer to the bias magnet. For this reason, the magnetic flux density applied to the semiconductor magnetic element when the object to be detected approaches can be increased, and applied to the semiconductor magnetic element when the object to be detected is close to the state away from the semiconductor magnetic element. The difference in the magnetic flux density to be made becomes remarkable, and the setting of the magnetic flux density threshold for switching becomes easy.

According to the second aspect of the present invention, since the holding member includes the mounting portion for the bias magnet, the semiconductor magnetic element, and the substrate, the holding member is in a state in which the bias magnet, the semiconductor magnetic element, and the substrate are sub-assembled with the holding member. Since the non-contact switch is assembled by engaging the terminal portion with the terminal base, the assembly of the non-contact switch is facilitated and the number of parts is reduced.

According to the third aspect of the present invention, if the concave portion is formed on the front surface facing the magnetic semiconductor magnetic element, there is no need to form the concave portion in the bias magnet, and a normal plate magnet, for example, is used. Therefore, the cost can be reduced.

According to the fourth aspect of the present invention, since the Hall element is used as the semiconductor magnetic element, even when the object to be detected approaches from the front as compared with the case where the magnetoresistive element (MR element) is used. High detection accuracy is maintained, and since it is not necessary to provide two elements like a magnetoresistive element, manufacturing cost can be kept low. In addition, when the non-contact switch is suitable for automobile use, a situation occurs in which the power is turned off halfway. When the power is turned on again, it is determined whether or not an object to be detected is approaching. be able to.

It is a disassembled perspective view of the non-contact switch which concerns on this invention. It is a top view of the non-contact switch concerning the present invention. It is the sectional view on the AA line of FIG. FIG. 4 is a sectional view taken along line BB in FIG. 3. It is a top view of the holding member of the non-contact switch concerning the present invention. It is CC sectional view taken on the line of FIG. It is a bottom view of the holding member of the non-contact switch concerning the present invention. It is a top view of the bias magnet of the non-contact switch concerning the present invention. (A)-(e) is a top view which shows the various form of the bias magnet used for the non-contact switch which concerns on this invention. It is a schematic diagram explaining the detection principle of the non-contact switch which concerns on this invention. It is typical sectional drawing which shows another form of the non-contact switch which concerns on this invention. It is a schematic diagram explaining the detection principle of the conventional non-contact switch. It is a schematic diagram which shows the example of improvement of the conventional non-contact switch.

Embodiments of the present invention will be described below with reference to the accompanying drawings.

  1 is an exploded perspective view of a non-contact switch according to the present invention, FIG. 2 is a plan view of the non-contact switch, FIG. 3 is a cross-sectional view taken along line AA in FIG. 2, and FIG. 5 is a plan view of the holding member, FIG. 6 is a sectional view taken along the line CC of FIG. 5, FIG. 7 is a bottom view of the holding member, and FIG. 8 is a plan view of the bias magnet.

  As shown in FIGS. 3 and 4, the non-contact switch 1 according to the present invention holds a hall element 3 as a semiconductor magnetic element, a bias magnet 4 and a substrate 5 arranged on the back side thereof in a switch body 2. The holding member 6 is accommodated, and a part of the terminal base 7 is fitted and fixed from the rear end opening of the switch body 2. In the non-contact switch 1, the left side in FIGS. 2 to 4 is the front and the right side is the rear.

  The switch body 2 is integrally formed in a hexagonal nut shape by zinc die casting or the like, and a bottomed cylindrical resin cap 8 is integrally mounted therein by insert molding or the like. The front end opening of the switch body 2 is closed by a cap 8.

  The holding member 6 includes a holding portion 6A and a pair of left and right arms 6B extending rearwardly from the holding portion 6A. A polygonal columnar block portion 6a is formed at the front end of the holding portion 6A. A rectangular concave element mounting portion 6b is formed on the front end surface of the block portion 6a.

  In addition, the holding portion 6A of the holding member 6 is formed with a magnet accommodating portion 6c that opens downward and on both sides, and as shown in FIG. 1, a circular vertical connecting the holding portion 6A and the arm portion 6B. A rectangular through hole 6e that is long in the horizontal direction is formed in the lower portion of the wall 6d. As shown in FIGS. 6 and 7, a pair of left and right press-fit pins 6f and engaging claws 6g are integrally projected downward from the lower surface of the block portion 6a of the holding member 6.

  Further, as shown in FIGS. 5 and 7, a board mounting portion 6h is formed at the front end portions of the left and right arm portions 6B of the holding member 6, and the outer portions of both arm portions 6B are shown in FIG. Thus, the latching claws 6i are respectively formed. As will be described later, the left and right locking claws 6 i constitute a locking portion for locking the terminal base 7.

  As shown in FIG. 1, three terminals 9 are led out from the Hall element 3, and these terminals 9 extend downward from the Hall element 3 and then are bent at a right angle toward the rear. .

  The bias magnet 4 is a magnet for generating a bias magnetic field, and a concave portion 4A is formed on the front surface thereof along the outer shape of the block portion 6a of the holding member 6. Here, as shown in FIG. 8, a portion close to the bottom surface of the opposing inner wall surface of the recess 4A formed in the bias magnet 4 is a tapered surface 4a. The shape of the recess 4A formed in the bias magnet 4 may be as shown in FIGS. 9 (a) to 9 (e). That is, an arcuate curved surface formed at the corner of the rectangular groove shown in FIG. 9 (a), an oval shape shown in FIG. 9 (b), a semicircular shape shown in FIG. 9 (c), The polygonal shape shown in FIG. 9D, the triangular shape shown in FIG.

  Thus, as shown in FIGS. 3 and 4, the hall element 3 is fitted into the element mounting portion 6 b formed on the front surface of the block portion 6 a of the holding member 6, and the three terminals extending from the hall element 3. 9 passes through the through hole 6e formed in the vertical wall 6d of the holding member 6 and extends rearward.

  Further, the bias magnet 4 is fitted from below into the magnet accommodating portion 6c of the holding member 6 with the concave portion 4A fitted to the block portion 6a of the holding member 6, and the block of the holding member 6 is blocked around the periphery of the concave portion 4A on the lower surface. The holding member 6 is temporarily held by engaging the engaging claws 6g formed on the portion 6a. The bias magnet 4 is held on the holding member 6 by the lid 10 shown in FIG. Here, as shown in FIG. 1, a concave groove 10 a for passing three terminals 9 extending from the hall element 3 is formed in the center in the width direction of the lid 10, and is formed on the left and right sides of the front end portion of the lid 10. A press-fitting groove 10b is formed, and engaging projections 10c are provided integrally on the left and right sides of the rear end portion in the rearward direction.

  Thus, the lid 10 has engaging protrusions 10c projecting on the left and right of the rear end portion thereof fitted in through holes 6e (see FIG. 1) formed in the vertical wall 6d of the holding member 6, and on the left and right of the front end portion. By inserting the left and right press-fitting pins 6f protruding from the block 6a of the holding member 6 into the formed press-fitting groove 10b, as shown in FIG. 3, a magnet housing portion is formed below the holding portion 6A of the holding member 6. The lid 10 is attached so as to cover the lower side, and the Hall element 3 and the bias magnet 4 are held by the holding member 6 by the lid 10 to prevent the holding member 6 from falling off.

  As shown in FIGS. 3 and 4, the substrate 5 is vertically mounted on the substrate mounting portion 6 h formed on the holding member 6, but three penetrations formed laterally are formed below the substrate 5. Three terminals 9 extending from the Hall element 3 penetrate through the hole 5a (see FIG. 1) and are electrically connected to the substrate 5. As shown in FIG. 1, three through holes 5 b are formed in the upper part of the substrate 5 in the lateral direction.

  The terminal base 7 is integrally formed with a rectangular cylindrical coupler portion 7A, and a flange portion 7B fitted to the inner peripheral portion of the switch body 2 is integrally formed at the front end portion of the coupler portion 7A. ing. Further, as shown in FIG. 1, locking holes 7 a that are long in the circumferential direction are formed in the left and right sides of the tip of the terminal base 7. The terminal base 7 is provided with three terminals 11 on the left and right sides for outputting an electric signal generated by the substrate 5 to an external device. Here, each terminal 11 is accommodated in the terminal base 7 in a state of being bent in a crank shape, and one end of each terminal 11 is formed in the three through holes 5b (FIG. 1) formed in the lateral direction above the substrate 5. And is electrically connected to the substrate 5. Further, the other end of the terminal 11 projects into the coupler portion 7A of the terminal base 7.

  Thus, as shown in FIGS. 3 and 4, the terminal base 7 has a flange portion 7B fitted into the switch body 2 from the rear end opening, and the rear end peripheral portion of the switch body 2 is caulked. It is fixed to the switch body 2.

  By the way, in the actual assembly, as shown in FIGS. 3 and 4, the Hall element 3, the bias magnet 4 and the substrate 5 are attached to the holding member 6 as described above and these are sub-assembled. 6A of holding parts 6A are fitted into the cap 8 mounted in the switch body 2 and fixed.

  Thus, in this embodiment, since the recess 4A is formed on the front surface of the bias magnet 4 facing the Hall element 3, the element mounting portion 6b of the holding member 6 is in the recess 4A inside the front surface of the bias magnet 4. The Hall element 3 attached to the element attaching portion 6 b is held so as to be separated from the bias magnet 4.

  Next, the detection principle of the object 12 to be detected by the non-contact switch 1 configured as described above will be described based on the schematic diagram shown in FIG.

  In the non-contact switch 1 according to the present invention, the recess 4A is formed on the front surface of the bias magnet 4 facing the Hall element 3, and the Hall element 3 is disposed in the recess 4A so as not to protrude from the front surface of the bias magnet 4. The front surface of the bias magnet 4 protrudes forward from the back surface of the Hall element 3 by a thickness distance b of the Hall element 3, and a space of a distance a shown in the figure is formed behind the Hall element 3.

  By the way, a bias magnetic field is applied to the Hall element 3 by the bias magnet 4, and the Hall element 3 arranged in the bias magnetic field generated by the bias magnet 4 has a detected object 12 made of a magnetic material as a solid line in FIG. 10. Detects the change in the bias magnetic field when separated as shown by the dotted line and when approached as shown by the chain line, and compares the detected magnetic flux density with a preset magnetic flux density threshold value to turn on / off The switching operation is performed.

  Thus, in the present embodiment, the Hall element 3 is held away from the bias magnet 4 by the element mounting portion 6b of the holding member 6, and a constant distance a is secured between them as shown in FIG. Thus, the magnetic flux density of the bias magnetic field applied to the Hall element 3 can be reduced in the state shown in FIG. Therefore, the difference in magnetic flux density applied to the Hall element 3 when the object 12 is separated as shown by the solid line in FIG. 10 and approached as shown by the chain line becomes significant, and the non-contact switch It is possible to easily set a magnetic flux density threshold for one switching.

  In the non-contact switch 1 according to the present invention, since the element mounting portion 6b of the holding member 6 is disposed in the recess 4A inside the front surface of the bias magnet 4, the thickness of the Hall element 3 is larger than that of the conventional case. The detected object 12 can be brought closer to the bias magnet 4 by the distance b. Therefore, the magnetic flux density applied to the Hall element 3 when the detected object 12 approaches as shown by a chain line in FIG. 10 can be increased, and the detected object 12 is indicated by a solid line in FIG. Thus, the difference in the magnetic flux density applied to the Hall element 3 between the state separated from the Hall element 3 and the state close as indicated by the chain line becomes significant, and this also causes the switching of the non-contact switch 1. Setting of the magnetic flux density threshold is facilitated.

  In the present embodiment, as shown in FIG. 8, the inner wall surface of the recess 4A formed on the front surface of the bias magnet 4 facing the Hall element 3 is the tapered surface 4a. Distributed parallel to the front surface of the magnet 4. For this reason, even if the position of the Hall element 3 with respect to the bias magnet 4 varies slightly in the radial direction (XY axis direction when the longitudinal axis direction of the non-contact switch is the Z axis), the magnetic field component does not change greatly, and the Hall element 3 is high. Since mounting accuracy is not required, the assembling property of the Hall element 3 is improved.

  Further, in the non-contact switch 1 according to the present invention, the holding member 6 includes an element attachment portion 6b for attaching the Hall element 3, the bias magnet 4 and the substrate 5 respectively, a magnet accommodating portion 6c, and a substrate attachment portion 6h. Therefore, in the state where the Hall element 3, the bias magnet 4 and the substrate 5 are sub-assembled with the holding member 6, the non-contact is achieved by locking the locking claw 6 i of the holding member 6 in the locking hole 7 a of the terminal base 7. Since the switch 1 is assembled, the non-contact switch 1 can be easily assembled and the number of parts can be reduced.

  In this embodiment, since the Hall element 3 is used as the semiconductor magnetic element, it is high even when the detection object 12 approaches from the front as compared with the case where the magnetoresistive element (MR element) is used. The detection accuracy is maintained, and since it is not necessary to provide two elements like a magnetoresistive element, the manufacturing cost can be kept low. In addition, when the non-contact switch 1 is suitable for an automobile application, a situation where the power is turned off occurs halfway, but it is determined whether or not the detected object 12 is approaching when the power is turned on again. Can be determined.

  In the above embodiment, the concave magnet 4A is formed in the bias magnet 4. However, as schematically shown in FIG. 11, the bias magnet 4 is divided into upper and lower parts, and a magnetic body is formed by the two divided bias magnets 4. Alternatively, a configuration in which a recess 13A is formed on the front surface of the magnetic body 13 facing the Hall element 3 may be employed. By adopting such a configuration, it is not necessary to form a concave portion in the bias magnet 4, and a normal plate-like magnet can be used as the bias magnet 4, so that the cost can be reduced.

1 Non-contact switch 2 Switch body 3 Hall element (semiconductor magnetic element)
4 Bias magnet 4A Bias magnet recess 4a Bias magnet recess taper surface 5 Substrate 5a, 5b Substrate through hole 6 Holding member 6A Holding member holding portion 6B Holding member arm 6a Holding member block 6b Holding member Element mounting portion 6c Holding member magnet housing portion 6d Holding member vertical wall 6e Holding member through hole 6f Holding member press-fit pin 6g Holding member engaging claw 6h Holding member substrate mounting portion 6i Holding member locking claw ( Locking part)
7 Terminal Base 7A Terminal Base Coupler 7B Terminal Base Flange 7a Terminal Base Locking Hole 8 Cap 9 Terminal 10 Lid 10a Lid Groove 10b Lid Pressing Groove 10c Lid Engaging Protrusion 11 Terminal 12 Detected Object 13 Magnetic body 13A Recess of magnetic body

Claims (4)

A bias magnet that generates a bias magnetic field, a semiconductor magnetic element that is disposed in the bias magnetic field generated by the bias magnet and detects a change in the bias magnetic field due to the approach of a detection object made of a magnetic material, and holds the bias magnet In a non-contact switch that includes a holding member that detects the position of the detected object,
Forming an element mounting portion on the holding member for holding the semiconductor magnetic element away from the bias magnet ;
Forming a recess in the front surface of the bias magnet facing the semiconductor element, and disposing an element mounting portion of the holding member in the recess;
A non-contact switch , wherein an inner wall surface of the concave portion of the bias magnet is a tapered surface, and an area having the same magnetic flux density is distributed in parallel to the front surface of the bias magnet . A latch for latching a terminal base having a board mounting portion for holding a board to which the semiconductor magnetic element is electrically connected to the holding member, and a terminal for outputting an electric signal generated by the board to an external device. non-contact switch according to claim 1 Symbol mounting, characterized in that part was formed. The non-contact switch according to claim 1 or 2, wherein the bias magnet is divided into a plurality of parts and a magnetic material is sandwiched between them. Non-contact switch according to any one of claims 1 to 3, characterized in that said semiconductor magnetic element and a Hall element.

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