JP2013205096A - Moving body detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a simply structured moving body detector having signal lines for improvement in measurement reliability by decreasing of stress applied on connecting parts of the signal lines and a magnetic sensing element.SOLUTION: The detector comprises: a magnetic sensing element 30; a permanent magnet 40; a substrate 50 to which the magnetic sensing element 30 and signal lines 1 are connected; a holder 20 holding the magnetic sensing element 30, the permanent magnet 40 and the substrate 50; a cap 10 having insertion ports 11 for the signal lines 1; and a case 60 having an opening fitting and being sealed with the cap 10 and housing the magnetic sensing element 30, the permanent magnet 40, the substrate 50, and the holder 20 inside. Both of the holder 20, fitting with the cap 10, and the cap 10 clip the signal lines and press the signal lines against the inner wall of the cap.

Description

  The present invention relates to a moving body detection device that magnetically detects a moving body that moves linearly or rotates, such as a rack or gear made of a magnetic material, and more particularly to a moving body detection device with a signal line.

  In general, this type of moving body detection device uses a soft magnetic material, such as a rack or rotor (gear), which has a plurality of convex shapes, to linearly move or to move the detected object that moves in a rotating manner. The sensor detects the change in the magnetic field caused by the object to be detected by the magnetic sensing elements (Hall IC, etc.) and the permanent magnet built in the moving object detection device. This is a configuration for outputting a simple pulse signal.

  This moving body detection device can constitute a rotation detection sensor that generates a regular pulse signal in accordance with the rotation of the rotor, and this is used for applications such as a speed sensor of an automobile.

  In particular, in applications such as speed sensors for automobiles, it is assumed that they will be used in a poor environment. Sometimes, the environment changes temperature from a high temperature to a low temperature, or dust, sludge, etc. Used in places where splashes. Therefore, it is necessary to protect the components inside the moving object detection device from the intrusion of dust, water, sludge, etc. from the outside.

  As a conventional configuration of this type of moving object detection device with a signal line, those proposed in Patent Document 1 and Patent Document 2 below are known.

JP 2002-181523 A JP 2000-171475 A

  In Patent Document 1, a double seal structure in which an electric circuit such as a signal conversion element is sealed by injecting a resin into a case and a case opening from which a signal line is drawn is sealed with a grommet and a lid member. Adopted.

  In Patent Document 2, an MR element, a magnet piece, and an amplifier are placed on a holder to perform primary molding (insert molding), a cable is crimped to a terminal of the holder, and this is secondary molded (insert molding).

  In Patent Document 1, when the signal line is pulled, the grommet and the injected resin cannot hold the signal line, and stress may be applied to the solder at the connection portion between the signal line and the substrate, resulting in poor conduction. This problem occurs especially when the injected resin is soft or the adhesion between the signal line insulation coating and the injected resin is not good. In addition, stress is applied to the sealed parts due to expansion or contraction of the injected resin, which may cause destruction or poor conduction.

  In Patent Document 2, there is a possibility that stress is applied to an electronic component such as a permanent magnet or an MR element due to a molding pressure at the time of insert molding, resulting in destruction. There is a possibility that the solder of the signal line connecting portion melts due to the heat of the resin at the time of insert molding, resulting in poor conduction. Further, in the case of double molding, a phenomenon of peeling at the interface between the primary molded product and the secondary molded product may occur.

  The present invention has been made in view of such a situation, and an object of the present invention is to provide a signal line that has a simple structure and can reduce the stress applied to the connection part of the signal line and the magnetic sensing element to improve the reliability. Another object of the present invention is to provide an attached moving body detection apparatus.

An aspect of the present invention is a moving body detection apparatus, a magnetic sensitive element, a permanent magnet that applies a magnetic field to the magnetic sensitive element, a substrate to which the magnetic sensitive element and the signal line are connected,
A holder for holding the magnetically sensitive element, the permanent magnet and the substrate;
A cap having an insertion opening for the signal line;
The cap has an opening to be fitted and sealed, and includes a case that houses the magnetically sensitive element, the permanent magnet, the substrate, and the holder inside,
The holder is fitted into the cap, sandwiches the signal line therebetween, and presses the signal line against the inner wall of the cap.

  The said aspect WHEREIN: The said cap and the said holder are good to have a latching | locking part engaged with each other.

  In the above aspect, the holder mounting surface of the cap is formed with a concave portion communicating with the insertion opening for the signal line, the holder has a columnar convex portion that fits into the concave portion, and the columnar convex portion is the concave portion. The columnar convex portion may be configured to press down the signal line in a state where the signal line is fitted.

  In the above aspect, the holder mounting surface of the cap is formed with a plurality of recesses communicating with the signal line insertion port, the holder has the same number of columnar projections as the recesses, and among the columnar projections, A rib may be formed on a side surface of at least one columnar convex portion, and the columnar convex portion may be configured to be press-fitted into the concave portion while crushing the rib with an inner wall of the concave portion.

  In the above aspect, it is preferable that a protrusion for partially pressing the insulating coating of the signal line is formed at the tip of the columnar convex portion.

  In the above aspect, the signal line that has passed through the insertion opening of the signal line bends in the cap and enters the holder, and the signal line is pressed by the columnar protrusion in the insertion direction of the columnar protrusion. It is good also to hold down also in the direction perpendicular | vertical to the side surface of the said columnar convex part.

  In the above aspect, the recess communicating with the signal line insertion port has a curved guide surface that bends the signal line by approximately 90 degrees, and the holder guides the signal line end to the signal line connection part of the substrate. The signal line that has passed through the insertion port by fitting the cap and the holder is positioned and guided to the signal line connection portion of the substrate through the curved guide surface and the guide hole. There should be.

  The said aspect WHEREIN: The insertion opening of the signal wire | line of the said cap is sealed with the grommet, and the said grommet is good to be hold | suppressed with the said cap or the said holder.

  The said aspect WHEREIN: It is good to seal by interposing an O-ring between the said cap and the said case.

  It should be noted that any combination of the above-described constituent elements, and those obtained by converting the expression of the present invention between other methods and systems are also effective as an aspect of the present invention.

  According to the present invention, the structure is simple and the stress applied to the connection portion of the signal line and the magnetically sensitive element can be reduced to improve the reliability. That is, when the holder is fitted to the cap, the signal line is sandwiched between the two, and the signal line is pressed against the inner wall of the cap, thereby ensuring sufficient tensile strength of the signal line and connecting the signal line and the substrate. It is possible to reduce the stress applied to the part and prevent a failure such as disconnection.

  In addition, the magnetic sensitive element does not need to be fixed by fixing the periphery by resin injection or insert molding, and stress due to expansion and contraction of the resin is not applied.

BRIEF DESCRIPTION OF THE DRAWINGS It is embodiment of the mobile body detection apparatus which concerns on this invention, Comprising: (A) is the external appearance perspective view of a completion state, (B) Side sectional drawing. It is an embodiment, (A) is an exploded perspective view seen from the case bottom side, (B) is an exploded perspective view seen from the opposite side. It is embodiment, (A) is an exploded side view, (B) is an exploded front view. In an embodiment, (A) is an exploded front view before fitting of a holder and a cap, (B) is the exploded side view, and (C) is a front view after fitting. In embodiment, (A) is a bottom view which shows the holder mounting surface of a cap, (B) is a top view of a holder, (C) is a side view of the columnar convex part in which the rib was formed in the holder. It is the perspective view which looked at the holder in embodiment from the upper part. FIG. 4 is an assembly procedure of each component in the embodiment, wherein (A) is an exploded side sectional view of a step of inserting a signal line into the cap, and (B) is an exploded side sectional view of a step of fitting the cap and the holder. (C) is a sectional side view of the process of fitting a cap and a case together. It is a principal part expanded side sectional view which shows the modification 1 of this invention. It is a principal part expanded sectional side view which shows the modification 2 of this invention.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In addition, the same code | symbol is attached | subjected to the same or equivalent component, member, process, etc. which are shown by each drawing, and the overlapping description is abbreviate | omitted suitably. In addition, the embodiments do not limit the invention but are exemplifications, and all features and combinations thereof described in the embodiments are not necessarily essential to the invention.

  1 to 3 show the overall configuration of an embodiment of a moving object detection apparatus with signal lines according to the present invention. As shown in these drawings, the moving body detection apparatus with a signal line holds a cap 10 having an insertion port 11 for a signal line 1 that is an insulation-coated wire, a magnetic sensing element 30, a permanent magnet 40, and a substrate 50. A holder 20 and a bottomed cylindrical case 60 in which the cap 10 is fitted and sealed are provided. The cap 10, the holder 20, and the case 60 are resin molded products of the same material. The magnetic sensitive element 30 is, for example, a Hall IC, and the permanent magnet 40 applies a predetermined bias magnetic field to the magnetic sensitive element 30, and is a ferrite magnet or a rare earth magnet.

  The concave / convex fitting structure between the cap 10 and the holder 20 will be described with reference to FIGS. In these drawings, illustration of the signal line 1, the magnetic sensitive element 30, the permanent magnet 40, and the substrate 50 is omitted. The cap 10 has three insertion ports 11 corresponding to the three signal lines 1 as shown in FIGS. 4A and 4C, and a holder mounting surface (see FIG. 5A). In the bottom surface, three recesses 12 communicating with the three insertion ports 11 are opened. The cap 10 integrally has a pair of locking claws 13 (one locking portion) extending from the holder mounting surface toward the holder side.

  The holder 20 integrally includes three columnar convex portions 21 that fit into the openings of the three concave portions 12 on the cap 10 side, and a locking portion 22 (the other side) with which the pair of locking claws 13 engage (hook). ) On both sides. As shown in FIGS. 4A, 4 </ b> C, and 6, a guide hole 23 through which the signal line 1 passes is formed at the base of each columnar convex portion 21. In order to position the signal line 1 by partially closing the front openings of the guide holes 23, a line pressing convex portion 14 protrudes from the holder mounting surface of the cap 10 toward the holder.

  A protrusion 21 a is formed at the tip of each columnar protrusion 21. Although the operation will be described later, the projection 21a is for partially pressing (breaking in) the insulating coating 1b of the signal line 1 to ensure the tensile strength of the signal line 1. Also, ribs 24 are formed on the side surfaces of the columnar protrusions 21. When the cap 10 and the holder 20 are fitted, each columnar protrusion 21 on the holder 20 side is inserted into the recess 12 on the cap 10 side. Sometimes, the columnar convex portion 21 is press-fitted into the concave portion 12 while crushing the rib 24 with the inner wall of the concave portion 12 (light press-fitting). Thereby, the cap 10 and the holder 20 can be fitted and integrated without rattling without using an adhesive.

  The ribs 24 may be formed on all the columnar protrusions 21, but the ribs 24 may be formed on the side surfaces of at least one of the columnar protrusions 21.

  Although not shown in FIGS. 4 to 6, in actual assembly, as shown in other drawings, an elastic grommet 15 is fitted inside the insertion slot 11 of the cap 10, and the signal line 1 is passed through the grommet 15. Is inserted through the cap 10 for a predetermined length (retracted). The insertion opening 11 of the signal line 1 of the cap 10 is hermetically sealed by the grommet 15.

  The holder 20 has a permanent magnet storage recess 25, an element placement recess 26, and a substrate mounting surface 27. The permanent magnet 40 is fixedly placed in the permanent magnet storage recess 25 without being rattled by press-fitting or the like. The magnetic sensitive element 30 is arranged, and the lead wire of the magnetic sensitive element 30 is soldered to a conductor pattern (not shown) of the substrate 50 fixed to the substrate mounting surface 27. An electronic component (not shown) constituting a detection signal processing circuit of the magnetic sensitive element 30 is mounted on the substrate 50. As shown in FIG. 3B, the substrate 50 is formed with connection holes 51 as three signal line connection portions into which the core wires 1a of the three signal lines 1 are inserted (the core wire 1a is connected to the connection hole 51). (A solder connection portion is obtained by performing a soldering process on a conductor pattern (not shown) around the).

  The bottomed cylindrical case 60 has a flange 61 extending laterally, and a mounting hole 62 is formed in the flange 61. The opening of the case 60 is sealed by fitting the cap 10 in which the O-ring 65 is disposed in the concave groove 18 that goes around the outer periphery of the fitting portion 17.

  The assembly procedure of the moving object detection apparatus with signal lines will be described with reference to FIG. The signal line 1 is inserted into the cap 10 as shown in FIG. The signal line 1 can be inserted into the insertion slot 11 by inserting the signal line 1 through the grommet 15 in advance and press-fitting the grommet 15 into the insertion slot 11. The cap 10 has a recess 12 that communicates with the insertion port 11, but the recess 12 has a curved guide surface 12 a that bends the signal line 1 by approximately 90 degrees. The direction is changed and it becomes downward. An O-ring 65 is mounted in advance on the outer periphery of the fitting portion of the cap 10.

  Then, as shown in FIG. 7B, the cap 10 and the holder 20 after mounting each component are fitted and integrated. At this time, as described with reference to FIG. 4 and the like, after the pair of locking claws 13 on the cap 10 side is engaged with and hooked with the locking portion 22 on the holder 20 side, and once integrated, the cap 10 and the holder 20 It is no longer detached and assembly is easy. At the same time, the columnar convex portion 21 is press-fitted into the concave portion 12 while pressing the rib 24 with the inner wall of the concave portion 12 (light press-fitting), thereby forming a passage path of the signal line 1 along the columnar convex portion 21. As a result, the signal line 1 can be sandwiched between the cap 10 and the holder 20, and the signal line 1 can be pressed against the inner wall of the cap. More specifically, the signal line 1 is pressed by the columnar convex portion 21 in the insertion direction (arrow Y direction) of the columnar convex portion 21 and also in the direction perpendicular to the side surface of the columnar convex portion 21 (arrow X direction). Pressed down. That is, the signal line 1 is pressed in two directions (X and Y directions) by the cap 10 and the holder 20, and the tensile resistance is further increased.

  Further, since the protrusion 21a is formed at the tip of each columnar convex portion 21, the signal line 1 is formed by partially pressing the insulating coating 1b of the signal line 1 (increasing the amount of biting into the signal line 1). It is possible to increase the pressing force and to secure the tensile strength of the signal line 1. As a result, even if the signal line 1 is pulled, the stress is not applied to the solder connection portion of the substrate 50 to which the signal line 1 is attached.

  As shown in FIG. 4 and the like, ribs 24 are provided on the columnar convex portions 21 so that the caps 10 and the caps 10 are fitted by light press-fitting, so when the case 60 and the caps 10 are fitted in a later process. The positional deviation between the cap 10 and the holder 20 is suppressed.

  In addition, since the holder 20 has a guide hole 23 that guides the end of the signal line 1 to a connection hole 51 as a signal line connection part of the substrate 50, the insertion opening 11 can be inserted by fitting the cap 10 and the holder 20. The signal line 1 that has passed is positioned and guided to the connection hole 51 of the substrate 50 through the curved guide surface 12a and the guide hole 23 (the core line 1a of the signal line 1 is inserted into the connection hole 51). Thereafter, necessary processing such as soldering is performed on the substrate 50.

  Finally, as shown in FIG. 7C, the cap 10 after integrating the holders 20 on which the respective components are mounted is fitted into the opening of the bottomed cylindrical case 60. At this time, the cap 10 and the case 60 are hermetically sealed with an O-ring 65 interposed therebetween, and the insertion port 11 of the cap 10 is hermetically sealed with the grommet 15, so that it is surrounded by the cap 10 and the case 60. The holder 20, the magnetic sensitive element 30, the permanent magnet 40, and the substrate 50 on which electronic components are mounted are accommodated in the airtight space.

  In the above moving body detection device, the magnetic sensitive element 30 indicates that the magnetic field applied to the magnetic sensitive element 30 by the permanent magnet 40 changes with the movement of the soft magnetic body outside the bottom surface of the case 60 and the presence or absence of the soft magnetic body. , The detection signal is output via the signal line 1. The supply of power supply voltage and the like is also performed by external connection via any one of the signal lines 1. As an example actually used, there is a rotation sensor or the like that reads the rotation of the gear with the unevenness of the gear.

  According to the present embodiment, the following effects can be achieved.

(1) The structure is simple, and the stress applied to the connection portion of the signal line 1 and the magnetic sensitive element 30 can be reduced to improve the reliability. That is, when the holder 20 is fitted to the cap 10, the signal line is sandwiched between the two and the signal line 1 is pressed against the inner wall of the cap, thereby ensuring sufficient tensile strength of the signal line 1. It is possible to reduce a stress applied to a connection portion (for example, a solder connection portion) between the substrate 50 and the substrate 50, thereby preventing a failure such as disconnection.

(2) On the holder mounting surface of the cap 10, a concave portion 12 communicating with the insertion port 11 is formed. The holder 20 has a columnar convex portion 21 that fits into the concave portion 12, and the columnar convex portion 21 fits into the concave portion 21. The columnar convex portion 21 presses the signal line 1 in the combined state, and the signal line 1 is inserted in the insertion direction of the columnar convex portion 21 (arrow Y direction) by the columnar convex portion 21 as shown in FIG. In addition to being pressed down, it is also pressed in the direction (arrow X direction) perpendicular to the side surface of the columnar convex portion 21 (pressed in two directions).

(3) Since the projection 21a is formed at the tip of each columnar convex portion 21, the insulation coating 1b of the signal line 1 is partially pressed (bite in) to further secure the tensile strength of the signal line 1. be able to.

(4) Ribs 24 are formed on the side surface of the columnar convex portion 21 on the holder side, and the columnar convex portion 21 is configured to be pressed into the concave portion 12 while crushing the rib 24 with the inner wall of the concave portion 12 on the cap side, The cap 10 and the holder 20 can be reliably fitted and integrated without rattling, and the use of an adhesive can be omitted.

(5) Since the holder 20 has the guide hole 23 that guides the end of the signal line to the connection hole 51 that becomes the signal line connection part of the substrate 50, the signal line 1 that has passed through the insertion port 11 is connected to the cap 10 and the holder 20. And is guided to the connection hole 51 of the substrate 50 through the curved guide surface 12a of the recess 12 and the guide hole 23, so that the workability at the time of assembly is good.

(6) Since the resin, molding resin, etc. poured into the electronic components mounted on the magnetic sensitive element 30 and the substrate 50 are not covered, no extra stress due to expansion or contraction of the resin is applied. For this reason, it is resistant to thermal shock, and no resin is required compared with the resin injection, and the cost can be reduced.

(7) Since the soldering is performed after the signal line 1 is fixedly connected to the substrate 50, no stress is applied to the solder connection part in the manufacturing process.

(8) When the cap 10 and the case 60 are fitted together, the O-ring 65 is interposed to ensure airtightness resistant to thermal expansion and contraction.

(9) Compared to Patent Documents 1 and 2, since no injection resin is required and no special molding is required like insert molding, manufacturing is easy and assembly workability is good.

  The present invention has been described above by taking the embodiment as an example. However, it is understood by those skilled in the art that various modifications can be made to each component and each processing process of the embodiment within the scope of the claims. By the way. Hereinafter, modifications will be described.

  FIG. 8 is an enlarged side cross-sectional view showing a main part of the first modification of the present invention. The grommet 15 is extended inward, and the inner side of the grommet 15 is extended by a protrusion 21a formed at the tip of the columnar convex portion 21 on the holder 20 side. It is the structure which presses a part. Other configurations are the same as those of the above-described embodiment. In Modification 1 of FIG. 8, the grommet 15 can be prevented from falling off by pressing the inner extension of the grommet 15 against the inner wall of the cap 10 with the protrusion 21 a.

  FIG. 9 is an enlarged side sectional view showing a principal part of a second modification of the present invention, in which a so-called under part, that is, a protruding part 11a toward the inner peripheral side is formed at the opening edge of the insertion port 11 into which the grommet 15 is press-fitted. It is. Since the opening diameter of the insertion port 11 is somewhat narrowed by the projecting portion 11a toward the inner peripheral side, the grommet 15 once press-fitted into the insertion port 11 does not fall off.

  The number of signal lines 1 can be increased or decreased as appropriate.

DESCRIPTION OF SYMBOLS 1 Signal wire 1a Core wire 1b Insulation coating | cover 10 Cap 11 Insertion slot 12 Recessed part 12a Curved guide surface 13 Locking claw 14 Line pressing convex part 15 Grommet 20 Holder 21 Columnar convex part 21a Projection 22 Locking part 23 Guide hole 24 Rib 25 Permanent magnet Storage recess 26 Magnetic sensitive element placement recess 27 Substrate mounting surface 30 Magnetic sensitive element 40 Permanent magnet 50 Substrate 60 Case 65 O-ring

Claims (9)

A magnetic sensitive element, a permanent magnet that applies a magnetic field to the magnetic sensitive element, a substrate to which the magnetic sensitive element and the signal line are connected,
A holder for holding the magnetically sensitive element, the permanent magnet and the substrate;
A cap having an insertion opening for the signal line;
The cap has an opening to be fitted and sealed, and includes a case that houses the magnetically sensitive element, the permanent magnet, the substrate, and the holder inside,
The holder is fitted to the cap, sandwiches the signal line therebetween, and presses the signal line against the inner wall of the cap.   The moving body detection apparatus according to claim 1, wherein the cap and the holder have a locking portion that engages with each other. The holder mounting surface of the cap is formed with a recess communicating with the signal line insertion port,
The movable body according to claim 1, wherein the holder has a columnar convex portion that fits into the concave portion, and the columnar convex portion presses the signal line in a state where the columnar convex portion is fitted into the concave portion. Detection device. The holder mounting surface of the cap is formed with a plurality of recesses communicating with the signal line insertion port,
The holder has the same number of columnar convex portions as the concave portions, and among the columnar convex portions, ribs are formed on the side surfaces of at least one columnar convex portion,
The moving body detecting device according to claim 3, wherein the columnar convex portion is press-fitted into the concave portion while crushing the rib with an inner wall of the concave portion.   The moving body detection apparatus according to claim 3 or 4, wherein a projection that partially presses the insulating coating of the signal line is formed at a tip of the columnar convex portion.   The signal line that has passed through the insertion opening of the signal line is bent in the cap and enters the holder, and the signal line is pressed in the insertion direction of the columnar protrusion by the columnar protrusion and the columnar protrusion. The moving body detection apparatus of any one of Claims 3 thru | or 5 pressed down also in the direction perpendicular | vertical to the side surface.   The concave portion communicating with the signal line insertion port has a curved guide surface that bends the signal line by approximately 90 degrees, and the holder has a guide hole that guides the signal line end to the signal line connection portion of the substrate, The signal line that has passed through the insertion port by fitting the cap and the holder is positioned and guided to the signal line connecting portion of the substrate through the curved guide surface and the guide hole. The moving body detection apparatus of any one of Claims.   8. The moving body detection device according to claim 1, wherein an insertion port of the signal line of the cap is sealed with a grommet, and the grommet is pressed by the cap or the holder.   The moving body detection device according to claim 1, wherein an O-ring is interposed between the cap and the case for sealing.

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