JP2005083912A - Rotation sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotation sensor having no possibility of causing contact between each connection cable run caused by deformation of the plurality of cable runs by a molding pressure at the insert molding time. <P>SOLUTION: A window part 27 for exposing partially each connection cable run 18a, 18b, 18c is formed on the body part 30 of a resin sealed member 20. Concerning formation of the window part 27, each external connection end 22 and each circuit connection end 25 of each connection cable run 18a-18c are fixed, and also each middle part 19 is fixed at prescribed intervals. Hereby, since each connection cable run 18a-18c is constrained at each middle part 19 at the molding time of the resin sealed member 20, deformation such as deflection is hardly generated at each middle part even when the molding pressure is applied to each middle part 19, to thereby suppress the contact between each connection cable run 18a-18c. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a rotation sensor suitable for use, for example, for detecting the rotation speed of a rotating part of a vehicle.

  2. Description of the Related Art Conventionally, a rotation sensor in which a magnetoelectric conversion element such as a Hall IC using a Hall effect is incorporated to detect the rotation speed of a rotating part of a vehicle is known.

  According to this rotation sensor, when the rotating part rotates, a peripheral magnetic field that changes according to the unevenness of the gear provided in the rotating part and rotating integrally with the rotating part is detected as a Hall voltage by the Hall IC. The detected hall voltage is converted into an electrical signal indicating the rotation speed of the rotating part through the circuit board to which the hall IC is electrically connected, and a plurality of connections extending from the circuit board for electrical connection of the circuit board It is output to the outside via the electric circuit. A permanent magnet for applying a bias magnetic field to the peripheral magnetic field is disposed in the vicinity of the Hall IC, and the detection sensitivity of the Hall IC is enhanced by this bias magnetic field (see, for example, Patent Document 1).

The plurality of connecting electric circuits are insert-molded at predetermined intervals between the ends of the plurality of connecting electric circuits so that the both ends protrude from the resin main body of the rotation sensor that supports the circuit board. Yes. For insert molding, an injection molding machine or the like that injects molten resin into a molding die at high pressure is used. When each connection electric circuit is insert-molded in the resin main body, each connection electric circuit is arranged at a predetermined insert position in the mold, and the mold is closed so that both ends of each connection electric circuit are sandwiched between the edges of the mold. Thereafter, molten resin, which is a molding material for the resin main body, is injected into the mold from an injection molding machine. At the time of insert molding, as long as a predetermined interval is maintained between the connection electric circuits, the connection electric circuits are insulated from the outside by the resin main body without short-circuiting.
Japanese Patent Laid-Open No. 2002-257588 (page 2-3, FIG. 9)

  However, when each connecting electric circuit is insert-molded in the main body, if a strong molding pressure due to the injection of molten resin from the injection molding machine acts on each end portion of each connecting electric circuit that is not sandwiched between the edges of the mold. There is a risk that deformation such as a large deflection may occur at each end portion. This large deflection causes a risk of contact between the connecting electric circuits.

  The objective of this invention is providing the rotation sensor which does not have a possibility of causing the contact of connection electric circuits by the deformation | transformation of several connection electric circuits by the shaping | molding pressure at the time of insert molding.

  In order to solve the above-mentioned problems, the invention described in claim 1 includes a magnetoelectric conversion element that converts a magnetic field that changes due to rotation of a magnetic body into an electrical signal, and a circuit board that is electrically connected to the magnetoelectric conversion element. A plurality of connection circuits extending from the circuit board for electrical connection of the circuit board, and a socket part allowing external connection to the plurality of connection circuits. And a resin sealing member for supporting the circuit board, wherein the main body portion of the resin sealing member is formed with a window portion for partially exposing the plurality of connection electric paths. .

  In the structure of Claim 1, the window part for exposing a some connection electric circuit partially is formed in the main-body part of the resin sealing member.

  A pair of stencils constituting a mold for molding the window portion into the main body portion is provided with a convex portion defining the window portion in the cavity into which the molten resin is injected, and the convex portion defining the window portion is formed. Each connecting electric circuit embedded in the main body is sandwiched between the parts. For this reason, during insert molding, each connection electric circuit is pinched | interposed into the edge part of each convex part, and is reliably fixed in a metal mold | die.

  Thereby, since each connection electric circuit becomes difficult to deform | transform even if it receives the molding pressure from an injection molding machine at the time of insert molding, and a predetermined space | interval is hold | maintained, the contact of connection electric circuits can be suppressed.

  Further, since the resin material for molding the resin sealing member is reduced by forming the window portion, the weight of the rotation sensor can be reduced.

  In addition, bubbles such as voids are likely to occur at the time of molding in the thick part, but the thickness around the window part of the main body part becomes thin due to the formation of the window part. The generation of bubbles such as voids is suppressed. As a result, the rotation sensor can function as a conventional sensor without losing strength.

  The invention according to claim 2 is the invention according to claim 1, wherein each of the connection electric paths is an intermediate portion arranged along the longitudinal direction of the main body within the main body of the resin sealing member, An external connection end portion extending from one end of the intermediate portion to the intermediate portion so as to protrude inward of the socket portion and connected to the outside, and the main body connected to the intermediate portion from the other end of the intermediate portion And a circuit connection end portion extending so as to protrude from the peripheral surface of the portion and connecting to the circuit board, and the intermediate portion is rectangular in cross section, and they are aligned with the plate thickness direction in the same direction. It is characterized by being arranged.

  In the configuration of the second aspect, each intermediate portion of each connection electric circuit has a rectangular cross section, and they are arranged with their plate thickness directions aligned in the same direction.

  If the thickness direction of each intermediate section of each connection circuit is not uniform, the degree of deformation due to molding pressure will be different because of the unevenness during insert molding due to the variation in molding pressure due to injection of molten resin from the injection molding machine. End up. For this reason, there is a possibility that a large deflection occurs in the intermediate portion having a high degree of deformation, and the intermediate portion having a low degree of deformation and a low degree of deflection may come into contact.

  On the other hand, in the configuration according to claim 2, since the intermediate portions of the connection electric circuits are arranged with the plate thickness directions aligned in the same direction, the molding pressure is, for example, different during insert molding. Even if it acts on each intermediate portion from either the thickness direction of the intermediate portion or the direction perpendicular thereto, each intermediate portion receives substantially the same molding pressure between the intermediate portions. Thereby, even if each intermediate part is deformed by the molding pressure, it is deformed while maintaining a certain distance from each other, so that contact between the connecting electric circuits can be suppressed.

  According to a third aspect of the present invention, in the second aspect of the present invention, the main body of the resin sealing member is detachably attached to the main body so as to cover the circuit board and the magnetoelectric transducer. A non-magnetic cylindrical cover member and an O-ring for improving the airtightness between the cylindrical cover member and the main body portion, and the window portion is the circuit of the O-ring and each connection circuit. It is formed between the connection end portions.

  In the configuration according to claim 3, since the window portion is formed between the O-ring and each circuit connection end portion of each connection electric circuit, in a state where the cylindrical cover member is attached to the main body portion, the window portion is It is reliably covered with a cylindrical cover member. For this reason, when the vehicle travels with the rotation sensor attached to the vehicle, water, dust, and the like are prevented from entering from the window during travel, so that water, dust, etc. adhere to each connection electric circuit. This can be prevented.

  According to this invention, the window part which exposes each connection electric circuit partially is formed in the main-body part of the resin sealing member. Since the deformation of each connection electric circuit is constrained with respect to the formation of this window portion, each connection electric circuit is held at a predetermined interval inside the main body of the resin sealing member. Can be suppressed.

  The rotation sensor according to the present invention will be described along examples.

  In this embodiment, an example in which the present invention is applied to a rotation sensor 10 for detecting the rotation speed of a transmission of a vehicle will be described.

  Although not shown in the drawings, the rotation sensor 10 according to the present invention has a peripheral magnetic field that changes according to the unevenness of the gear 11 due to the rotation of the gear 11 made of a magnetic material attached to the output shaft of the transmission, as is well known. It is detected as a voltage and is used as a detection device for converting it into an electrical signal indicating the rotational speed of the transmission.

  FIG. 1 is a longitudinal sectional view of a rotation sensor 10 according to the present invention. As shown in FIG. 1, the rotation sensor 10 includes an L-shaped resin molded member 20 formed of a synthetic resin material.

  The resin molded member 20 includes a main body 30 and a socket 40 that is connected to the main body and is perpendicular to the main body, and the main body 30 and the socket 40 form an L shape. The socket portion 40 is formed with a recess 14 for a socket defined by the peripheral wall 13.

  The main body 30 is formed with an elongated support portion 30a having a rectangular cross section. The support portion 30a generates a bias magnetic field to increase the detection sensitivity of the magnetoelectric conversion element 15 in contact with the magnetoelectric conversion element 15 and the circuit board 16 to which the magnetoelectric conversion element is electrically connected. The permanent magnet 17 is supported. The magnetoelectric conversion element 15 is attached to the tip of the support portion 30a. In the illustrated example, the magnetoelectric conversion element 15 is configured by a Hall IC 15 that uses a Hall effect in which a Hall element and an amplifier circuit (not shown) are sealed. Although not shown in the drawings, the circuit board 16 is an electric circuit that incorporates electronic components necessary to supply power to the Hall IC 15 and to perform predetermined electrical processing on the output signal from the Hall IC, as is well known. A circuit is formed.

  The main body 30 is formed with a mounting portion 30b for detachably mounting a cylindrical cover member 50 formed of a nonmagnetic material. One end of the mounting portion 30 b is continuous with the base end of the support portion 30 a, and the other end of the mounting portion 30 b is continuous with the socket portion 40. An O-ring 26 is attached to the mounting portion 30b.

  The cylindrical cover member 50 has a cylindrical shape, one end of which is closed and the other end is opened. The cylindrical cover member 50 is attached to the attachment portion 30b via the O-ring 26 so as to cover the Hall IC 15, the circuit board 16, the permanent magnet 17 and the support portion 30a that supports them from the other open end. The O-ring 26 enhances the airtightness between the cylindrical cover member 50 and the mounting portion 30b when the cylindrical cover member 50 is mounted on the main body 30. As a result, the Hall IC 15, the circuit board 16, and the permanent magnet 17 are watertightly accommodated in the cylindrical cover member 50.

  As shown in FIGS. 1 and 2, three connection electrical paths 18 a, 18 b, and 18 c are insert-molded at a predetermined interval in the main body 30. Thereby, the resin molding member 20 seals each connection electric circuit 18a-18c in the inside.

  Each of the connection electric paths 18 a to 18 c has a rectangular cross section, and the intermediate portion 19 disposed in the mounting portion 30 b of the main body portion 30 along the longitudinal direction of the main body portion 30, and the socket portion 40 of the intermediate portion 19. From the one end 21 leading to the intermediate portion, the outer connecting end portion 22a extends in the mounting portion 30b at a right angle and the tip portion 22a protrudes inward of the recess 14 of the socket portion 40, and the support portion 30a of the intermediate portion 19 The other end 23 is provided with a circuit connection end portion 25 that extends in the support portion 30a at a right angle to the intermediate portion and the tip portion 25a protrudes from the upper surface 24 of the support portion 30a. Each distal end portion 22a of each external connection end 22 can be connected to a device that receives rotation information of the rotating body from the rotation sensor 10 and displays the rotation speed of the rotating body, for example. Each tip 25a is connected to the circuit board 16 by soldering. Thereby, each connection electric circuit 18a-18c is either a terminal for the power supply for supplying an electric current to Hall IC15, the output for outputting to the exterior from Hall IC15, or a ground similarly to the past, respectively. Serves as a function.

  As shown in FIG. 2, among the three connection electric circuits 18a to 18c, with respect to the linear intermediate portion 19 of the connection electric circuit 18b arranged between the connection electric circuits 18a and 18c arranged on both sides, each connection electric circuit 18a, The pair of intermediate portions 19 having a crank shape of 18c are arranged symmetrically so that the distance between them becomes smaller at the support portion 30a. Moreover, the intermediate part 19 of the connection electric circuit 18b arrange | positioned between the connection electric circuits 18a and 18c of both sides is arrange | positioned below the intermediate part 19 of the connection electric circuits 18a and 18c of both sides seeing in FIG. For this reason, as shown in FIG. 3 which is GG sectional drawing of FIG. 2, each intermediate | middle part 19 has comprised each vertex of a triangle. Further, the intermediate portions 19 are arranged in parallel so that their plate thickness directions are aligned with each other along the plate thickness direction of the support portion 30a.

  The external connection end portions 22 are arranged in alignment on a cross section across the socket portion 40.

  Both circuit connection ends 25 of the connection electric circuits 18a and 18c on both sides are arranged in alignment on a cross section crossing the support portion 30a, and the circuit connection of the connection electric circuit 18b arranged between the connection electric circuits 18a and 18c. The end portion 25 is disposed at a position farther from the tip of the support portion 30a than the circuit connection end portions 25 of the connection electric paths 18a and 18c disposed on both sides thereof. For this reason, as shown in FIG. 2, each front-end | tip part 25a of each circuit connection end part 25 protrudes from the upper surface 24 of the support part 30a so that each protrusion position may comprise each vertex of a triangle.

  In the support portion 30a, a rectangular window portion 27 is formed between the O-ring 26 and each circuit connection end portion 25 so as to penetrate the support portion 30a in the plate thickness direction. Due to the formation of the window portion 27, the intermediate portions 19 arranged so that the plate thickness directions thereof are along the plate thickness direction of the support portion 30a are partially exposed from the window portion 27 as shown in FIG. . The window portion 27 is reliably covered with the cylindrical cover member in a mounted state of the cylindrical cover member 50 to the mounting portion 30b of the main body portion 30. For this reason, it is prevented that water, dust, etc. penetrate | invade from the window part 27 during driving | running | working of a vehicle, and, thereby, water, dust, etc. are prevented from adhering to each connection electric circuit 18a-18c.

  In the attachment of the rotation sensor 10, as shown in FIG. 1, the Hall IC 15 supported at the tip of the support portion 30a of the main body 30 is opposed to the gear 11 made of a magnetic material attached to the output shaft of the transmission. A rotation sensor 10 is attached to a transmission case (not shown).

  When the gear 11 rotates, a peripheral magnetic field that changes according to the unevenness of the gear 11 is detected by the Hall IC 15 as a Hall voltage. The detected hall voltage is converted into an electric signal indicating the rotational speed of the transmission by the circuit board 16 to which the hall IC 15 is connected, and the electric signal is connected to each circuit connection end of each connection electric circuit 18 a to 18 c connected to the circuit board 16. From each of the external connection end portions 22 projecting inward of the recess 14 of the socket portion 40 through the intermediate portions 19 from the portion 25, the rotation speed of the transmission is output to the above-described device.

  The rotation sensor 10 according to the present invention is formed by insert molding. A part of the mold 60 for insert molding is shown in FIG.

  As shown in FIG. 4, a pair of mold plates 28 a and 28 b constituting the mold 60 is provided with each mold plate 28 a to which molten resin for molding the resin molding member 20, that is, the resin sealing member 20 is injected. A convex part 31 that defines the window part 27 is formed in the cavity 29 of 28b. The end surfaces of the convex portions 31 can contact each other with the mold 60 closed, and grooves 31a for receiving the intermediate portions 19 of the connection electric paths 18a to 18c are formed on the end surfaces.

  When insert-molding the connection electric paths 18a to 18c, the intermediate portions 19 of the connection electric paths 18a to 18c are spaced apart from each other by a predetermined interval with the plate thickness direction in the direction between the protrusions 31. Is disposed in the groove 31a. Each front end 25a of each circuit connection end 25 and each front end 22a of each external connection end 22 (not shown) are recessed to receive the front end 25a formed in each cavity 29 and the protruding position of each front end 22a. Restrained at location 32. When the mold 60 is closed and the end faces of the convex portions 31 are brought into contact with each other, the intermediate portions 19 of the connection electric paths 18 a to 18 c are sandwiched between the convex portions 31. Thereby, each intermediate part 19 of each connection electric circuit 18a-18c is reliably fixed in the metal mold | die 60, maintaining a predetermined space | interval. Thereafter, the molten resin is injected into the mold 60 at a high pressure by a molding machine such as an injection molding machine.

  According to the present embodiment, as described above, the support portion 30a of the main body portion 30 is formed with the window portion 27 that partially exposes the intermediate portions 19 of the connection electric paths 18a to 18c. Regarding the formation of the window portion 27, the circuit connection end portions 25 and the external connection end portions 22 of the connection electric paths 18 a to 18 c are fixed in a mold 60 for forming the window portion 27 as in the prior art. In addition, each intermediate portion 19 is fixed in the mold 60 at a predetermined interval. Thereby, since each connection electric circuit 18a-18c is restrained between those both ends, even if each connection electric circuit 18a-18c receives a molding pressure at the time of insert molding of each connection electric circuit 18a-18c to the main-body part 30, Since it becomes difficult to produce deformation | transformation, such as bending, in each connection electric circuit, the contact of each connection electric circuit 18a-18c can be suppressed.

  Moreover, since the resin material for shape | molding the resin sealing member 20 reduces by formation of the window part 27, the weight reduction of the rotation sensor 10 can be achieved.

  Furthermore, although bubbles such as voids are likely to be generated at the time of molding in the thick portion, the thickness of the periphery of the window portion 27 of the support portion 30a is reduced by the formation of the window portion 27, so that the resin sealing member 20 is molded. Occurrence of bubbles such as voids around the window 27 is sometimes suppressed. Thereby, the rotation sensor 10 can fulfill the same sensor function as before without losing the strength.

  Further, as described above, the intermediate portions 19 of the connection electric paths 18a to 18c are arranged in parallel with their plate thickness directions aligned with each other along the plate thickness direction of the support portion 30a of the main body portion 30. ing. Thereby, at the time of insert molding of each connection electric circuit 18a-18c in the main-body part 30, the molding pressure by injection | pouring of the molten resin from an injection molding machine is either the plate | board thickness direction of each intermediate part 19, or a direction orthogonal to this, for example Even if it acts on each intermediate portion 19 from the direction, each intermediate portion 19 receives substantially the same molding pressure between the intermediate portions 19. From this, even if each intermediate portion 19 is deformed by the molding pressure, it is deformed while maintaining a certain distance from each other, so that contact between the connection electric paths 18a to 18c can be suppressed. In addition, since the intermediate portions 19 are arranged with their plate thickness directions oriented in the same direction, the intermediate portions 19 are securely and easily sandwiched by the convex portions 31 that define the window portions 27 during insert molding, Each intermediate portion 19 can be securely fixed in the mold 60.

  Furthermore, the window part 27 formed in the support part 30a of the main body part 30 is formed between the O-ring 26 provided in the main body part 30 and the circuit connection end parts 25 of the connection electric paths 18a to 18c. Therefore, when the cylindrical cover member 50 is mounted on the mounting portion 30b of the main body 30, the cylindrical cover member is surely covered. By mounting the cylindrical cover member 50, it is possible to prevent water, dust, and the like from entering from the window portion 27 during traveling of the vehicle, and thereby water, dust, and the like adhere to the connection electric paths 18a to 18c. This can be prevented.

  In the present embodiment, the plurality of connection electric paths 18a to 18c are embedded in the main body portion 30 with their plate thickness directions aligned with each other along the plate thickness direction of the support portion 30a. Further, the plate thickness direction can be aligned and arranged along the direction perpendicular to the plate thickness direction of the support portion 30a. Moreover, although the some connection electric circuit 18a-18c showed the example which has a rectangular cross section, it replaced with this connection electric circuit 18a-18c, for example, connected the electric circuit which has a circular cross section or a square cross section. It can also be used. Further, each external connection end 22 and each circuit connection end 25 of each connection electric circuit 18a to 18c extends from each end 21 and each other end 23 of each intermediate portion 19 at right angles to each intermediate portion 19. However, it is also possible to use a connection circuit that extends from each intermediate portion 19 at an angle other than a right angle.

  In the present embodiment, an example in which the window portion 27 formed in the support portion 30a of the main body portion 30 is rectangular has been described. However, the window portion 27 may be formed in a circular shape, for example. Moreover, although the window part 27 showed the example which has penetrated the support part 30a in the plate | board thickness direction, it does not need to penetrate.

  Further, in the present embodiment, an example in which the magnetoelectric conversion element 15 is configured by the Hall IC 15 is shown, but a magnetoresistive element or an anisotropic magnetoresistive element using the magnetoresistive effect is used instead of the Hall IC 15. Can do.

It is the longitudinal section showing the rotation sensor concerning the present invention roughly. It is the top view which showed schematically the state where Hall IC, a circuit board, an O-ring, and a cylindrical cover member are not attached to the rotation sensor concerning the present invention. It is GG sectional drawing in FIG. It is the schematic which showed a part of state in which each connection electric circuit is being fixed in the metal mold | die used in order to shape | mold the rotation sensor which concerns on this invention.

Explanation of symbols

11 Magnetic body (gear)
15 Magnetoelectric transducer (Hall IC)
16 Circuit board 18a, 18b, 18c Connection electric circuit 30 Main body part 40 Socket part 20 Resin sealing member (resin molding member)
27 Window portion 19 Intermediate portion 21 One end 22 External connection end portion 23 Other end 24 Peripheral surface (upper surface of support portion)
25 Circuit connection end 50 Cylindrical cover member 26 O-ring

Claims (3)

A magnetoelectric conversion element that converts a magnetic field that changes due to rotation of a magnetic body into an electrical signal, a circuit board that is electrically connected to the magnetoelectric conversion element, and extends from the circuit board for electrical connection of the circuit board A main body part in which a plurality of connection electric circuits are embedded, and a socket part that allows external connection to the plurality of connection electric circuits, and a resin sealing member that supports the circuit board,
The rotation sensor according to claim 1, wherein a window portion for partially exposing the plurality of connecting electric paths is formed in the main body portion of the resin sealing member. Each of the connection electric paths includes an intermediate portion disposed along the longitudinal direction of the main body portion within the main body portion of the resin sealing member, and an inner portion of the socket portion connected to the intermediate portion from one end of the intermediate portion. And an external connection end connected to the outside and extended from the other end of the intermediate portion, and extended from the peripheral surface of the main body portion and connected to the circuit board. A circuit connection end
2. The rotation sensor according to claim 1, wherein the intermediate portion has a rectangular cross section and is arranged so that the thickness directions thereof are aligned in the same direction. A nonmagnetic cylindrical cover member that is detachably attached to the main body so as to cover the circuit board and the magnetoelectric conversion element, and the cylindrical cover member and the main body of the resin sealing member An O-ring is provided to increase the airtightness with the part,
The rotation sensor according to claim 2, wherein the window portion is formed between the O-ring and the circuit connection end portion of each connection electric circuit.

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