JP2016070713A - Inductance-type noncontact rotation angle detector and motor-driven throttle valve control device equipped with same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inductance-type noncontact rotation angle detector capable of improving overmolding performance for a circuit board without eliminating the effect that assembly man-hours can be reduced, and a motor-driven throttle valve control device with the same.SOLUTION: An inductance-type noncontact rotation angle detector comprises: a rotor-side conductor which is attached to a rotary shaft of a rotating body; a stator-side conductor which is attached to a resin cover member facing the rotary shaft; and an electronic circuit which detects a rotation position of the rotating body using a change in an inductance between the two conductors in response to a positional relation therebetween in the rotation direction, the resin cover has a circuit board to which the stator-side conductor and a signal processing circuit are attached, a connector which is electrically connected to an external device, and an electric conductor which connects a connector terminal formed at the connector to the circuit board, and at least part of the circuit board and the electric conductor are constituted as one formed body formed by the same foamable resin.SELECTED DRAWING: Figure 5

Description

  The present invention relates to an inductance-type non-contact rotation angle detection device and a motor-driven throttle valve control device including the same.

  As this type of non-contact rotation angle detection device, one described in Japanese Patent No. 5298061 (Patent Document 1) is known. It is also known from Patent Document 1 that this type of rotation angle detection device is used as a rotation angle detection device of a motor-driven throttle valve control device.

Japanese Patent No. 5298061

  In a conventional inductive non-contact rotation angle detection device, a rectangular circuit board provided with a fixed-side conductor (excitation conductor and receiving coil conductor), an input / output drive unit and a control electronic circuit unit is covered with a resin cover. It was fixed to the surface of a resin-made gear cover (in a motor-driven throttle valve control device) by bonding. However, many work steps are required to complete the cover assembly, such as bonding the circuit board after molding the resin cover, and joining for electrical connection with the electric conductor wound around in the cover. There was a problem that the manufacturing cost was high.

  In Patent Document 1, in order to solve this problem, the resin cover includes a circuit board on which a fixed-side conductor and an electronic circuit are mounted, a connector for electrical connection with an external device, and a connector terminal formed on the connector. And an electric conductor for connecting the circuit board and at least a part of the circuit board and the electric conductor are proposed to be formed as one molded body made of the same resin.

  Preferably, the fixed-side conductor and the electric conductor fixed to the circuit board are configured as one molded body that is covered and molded with the same resin, and the molded body is further overmolded with a molding resin for the resin cover. Has been proposed.

Furthermore, in the prior art described in this patent document,
The resin used for the gear cover has good heat resistance, and if polybutylene terephthalate (PBT), etc., which is versatile, is used, a thermoplastic PBT material is used for insert molding including an electronic substrate.・ Because high-pressure injection molding is performed, electronic components mounted on the top surface of the board may be damaged by heat or shear stress generated during flow.
If you try to reduce the resin thickness on the top surface of the excitation conductor and the detection conductor, the resin flow will be worse, so it will be necessary to increase the resin molding pressure.
Proposed to obtain a molding resin made of PBT resin material with low fluidity and high fluidity by adjusting the molecular weight of PBT resin to increase fluidity or adding additives. And
The selection of this resin is not limited to the PBT resin, and can be selected from various thermosetting or thermoplastic resins depending on the properties of the overmold resin that forms the gear cover,
In addition, if a PBT material containing a low melting point polymer material is used, it can be molded at a temperature lower than the resin molding temperature required at the time of normal resin molding, so it can be used for circuit components and solder joints resulting from the resin temperature. It is disclosed that the entire circumference of the circuit board (excitation conductor, detection conductor, electronic circuit element and wiring conductor) can be insert-molded.

  However, even with these solutions, there is still a problem that the circuit board of the rotation angle detection device is distorted or cracked when the gear cover is molded with resin.

  Accordingly, the present invention provides an inductance-type non-contact rotation angle detection device that improves the overmoldability of a circuit board without losing the effect that the number of assembly steps can be reduced, and a motor-driven throttle valve control device including the same. The purpose is to provide.

  In order to solve the above problems, for example, the configuration described in the claims is adopted.

  The present application includes a plurality of means for solving the above-mentioned problems. To give an example, a rotating-side conductor attached to the rotating shaft of the rotating body, and a fixed-side conductor attached to the resin cover member facing the rotating conductor. An electronic circuit for detecting the rotational position of the rotating body by utilizing the fact that the inductance between the two conductors changes in accordance with the positional relationship between the two rotating directions, and a rotation angle detecting device comprising: The resin cover includes a circuit board on which the fixed-side conductor and the signal processing circuit are mounted, a connector for electrically connecting to an external device, and an electrical terminal for connecting a connector terminal formed on the connector and the circuit board. It has a conductor, At least one part of the said circuit board and the said electrical conductor are comprised as one molded object shape | molded by the same foaming resin, It is characterized by the above-mentioned.

  According to the present invention, an inductance-type non-contact rotation angle detection device that improves the overmoldability of a circuit board without losing the effect of reducing the number of assembly steps, and a motor-driven throttle valve control device including the same Can be provided.

  Problems, configurations, and effects other than those described above will be clarified by the following description of embodiments.

1 is an overall cross-sectional view of a motor-driven throttle valve device. The exploded front view of a motor drive type throttle device. The partial cross section figure of the rotation conductor of an inductance type rotation angle detection apparatus. The disassembled perspective view of the rotation conductor of an inductance type rotation angle detection apparatus. The perspective front view of an inductance type rotation angle detection apparatus. The whole perspective view of a TPS terminal. The expansion perspective view of the tip of a TPS terminal. The whole perspective view of a TPS substrate. The expansion perspective view of a TPS substrate through hole part. The partial cross section figure of the motor electrical junction of a motor drive type throttle valve apparatus. Bukumi whole perspective view of TPS board and terminal. The whole perspective view of an insert molded product. The whole perspective view of an inductance type rotation angle detection device. FIG. 4 is a perspective view of the entire TPS substrate and terminal according to the second embodiment. The whole perspective view of the insert molded product of Example 2. FIG. FIG. 6 is an overall perspective view of an inductance type rotation angle detection device according to a second embodiment. FIG. 10 is an overall perspective view of the TPS substrate and terminal of Example 3. FIG. 6 is an overall perspective view of an inductance type rotation angle detection device according to a third embodiment. The whole perspective view of the inductance type rotation angle detection device of Example 3 (after additional processing). The expansion perspective view of a TPS substrate. Bukumi whole perspective view (back surface) of the TPS substrate and the terminal of Example 4. The whole perspective view (front side) of the insert molded product of Example 4. FIG. Sectional drawing of the insert molded product of Example 4. FIG. The expanded sectional view of the insert molded product of Example 4. FIG. 9 is an overall perspective view of an inductance type rotation angle detection device according to a fourth embodiment. Insert molded product of Example 5 Overall perspective view of inductance type rotation angle detection device of embodiment 5

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

  First, the configuration of a motor-driven throttle valve device for an internal combustion engine according to this embodiment will be described with reference to FIGS.

  FIG. 1 is an overall cross-sectional view of a motor-driven throttle valve device (hereinafter abbreviated as ETB), and FIG. 2 is an exploded front view.

  An intake air passage 1 (hereinafter referred to as a bore) and a motor housing 2A for housing the motor 2 are formed together in a throttle valve assembly (hereinafter referred to as a throttle body) 3 made of aluminum die casting.

  A metal rotating shaft (hereinafter referred to as a throttle shaft) 4 is disposed on the throttle body 3 along one diameter line of the bore 1. Both ends of the throttle shaft 4 are rotatably supported by needle bearings 5, 6 or ball bearings. The needle bearings 5 and 6 are press-fitted and fixed to the throttle body 3. Further, after inserting a C-type washer (hereinafter referred to as a thrust retainer) 7 into a slit provided on the throttle shaft 4, a needle bearing 5 is press-fitted, thereby restricting the axial movable amount of the throttle shaft 4. .

  The throttle shaft 4 is assembled with a throttle valve (hereinafter referred to as a throttle valve) 8 for changing the air amount to the engine.

  Thus, when the throttle shaft 4 rotates, the throttle valve 8 rotates, and as a result, the opening area of the intake passage changes and the intake air amount of the internal combustion engine can be adjusted.

  A throttle gear 10 is fixed to the end of the throttle shaft 4 with a nut 11.

  The throttle gear 10 includes a metal plate 10A and a gear portion 10B formed by resin molding on the metal plate 10A.

  The motor housing 2 </ b> A is formed in parallel with the throttle shaft 4, and the brush type DC motor 2 is inserted into the motor housing 2 </ b> A and fixed with screws 12. A metal gear (hereinafter referred to as a motor gear) 13 having the smallest number of teeth is fixed to the end of the rotating shaft of the motor 2.

  Between the motor gear 13 and the throttle gear 10, a gear (hereinafter referred to as an intermediate gear) 15 instructed to rotate is engaged with a metal shaft 14 (hereinafter referred to as an intermediate gear shaft) press-fitted and fixed to the throttle body 3. ing. The intermediate gear 15 includes a large-diameter gear 15A that meshes with the motor gear 13 and a small-diameter gear 15B that meshes with the throttle gear 10. Both gears of the intermediate gear 15 are integrally formed by resin molding.

  These gears 13, 15A, 15B, 10 constitute a two-stage reduction gear mechanism, and thus the rotation of the motor 2 is transmitted to the throttle shaft 4 through the reduction mechanism.

  A return spring 16 formed of a string-wound spring is sandwiched between the back surface of the throttle gear 10 and the side surface of the throttle body 3. One end of the return spring 16 is locked to a notch formed in the throttle body 3, and the other end is locked to a notch formed in the throttle gear 10. The return spring 16 is preloaded in the rotational direction so that the throttle valve 8 maintains the fully open position when the motor 2 is not energized.

  Next, a method of mounting the inductance type rotation angle detection device will be described with reference to FIGS.

  FIG. 3 is a partial cross-sectional view of the rotating conductor of the inductance type rotation angle detecting device, and FIG. 4 is an exploded perspective view of the rotating conductor.

  As described above, the inductance-type rotation angle detection device includes a conductor attached to the rotating shaft of the rotating body and a conductor attached to the stator facing the rotor. The former corresponds to a disc (hereinafter referred to as a rotor) 17 shown in FIGS. 3 and 4, and the latter corresponds to a circuit board (hereinafter referred to as a TPS board) 18.

  An excitation conductor 17A is printed on the rotor 17, and the rotor 17 is bonded and fixed to a holder (hereinafter referred to as a rotor holder) 19 on a cup formed of a resin molded body. A metal rotor holder inserter 19 </ b> A is integrally formed at the center of the rotor holder 19.

  A positioning through hole 17B is formed at the center of the rotor 17, and a positioning projection 19B corresponding to the through hole 17B is formed in the rotor holder inserter 19A. Thereby, the central axes of the rotor 17 and the rotor holder 19 are made to coincide. An annular window hole 19C is provided on the central axis of the rotor holder inserter 19A, and this is press-fitted and fixed to the throttle shaft 4. Thus, the rotor 17 rotates in the same manner as the throttle shaft 4.

  Hereinafter, the component configuration of the present embodiment will be described in detail with reference to FIG. FIG. 5 is a perspective front view of the inductance type rotation angle detection device (hereinafter, “TPS” means “rotation angle detection device”).

  The TPS substrate 18 is printed with an annular excitation conductor 18A1 and a plurality of detection conductors 18A2 arranged in the radial direction, and this conductor is a drive power supply unit and a rotation position (angle) of the rotation position (angle) detection unit. It becomes a detection part. An electronic circuit element 18B including a microcomputer is provided on the TPS substrate 18, and drive control and output signal processing of the rotation angle detection unit are performed by this circuit. The TPS substrate 18 is mounted in a cover (hereinafter referred to as a gear cover) 20 of a resin molded product.

  In the gear cover 20, six metal wiring conductors are installed. The wiring conductors can be roughly divided into four TPS wiring conductors 21 and two motor wiring conductors 22. The connector 20B is formed into a connector 20B. When the vehicle is mounted, an electric wire extending from the engine control unit is joined to the connector 20B by an insertion plug, whereby an electrical signal is transferred, electric power is supplied, and connection to the ground is performed. This metal wiring conductor is subjected to insert molding (referred to as pre-molding) in order to improve the position of each wiring conductor before performing exterior molding (referred to as overmolding). At this time, the TPS substrate 18 mounted in the gear cover 20 is also insert-molded together with the wiring conductor. The insert molding will be described later with reference to another drawing.

  Next, a method for connecting the TPS substrate 18 and the TPS wiring conductor 21 will be described with reference to FIGS. FIG. 6 is an overall perspective view of the TPS wiring conductor 21, and FIG. 7 is an enlarged view of the tip portion thereof. FIG. 8 is an overall perspective view of the TPS substrate 18, and FIG. 9 is an enlarged view of the connecting portion.

  Before the TPS wiring conductor 21 and the TPS substrate 18 are simultaneously insert-molded, the four TPS wiring conductors 21 are electrically connected in advance. In order to make an electrical connection, a metal member is interposed on the inner wall of the wiring through hole 18D provided on the TPS substrate 18. Then, the connecting terminal 21A on the side opposite to the connector of the TPS wiring conductor 21 having an elastic structure is pushed into the wiring through hole 18D provided on the TPS substrate 18 while being pressed. At that time, by pressing the wiring conductor having a size larger than the inner dimension of the wiring through hole 18D, the expansion portion provided in the connection terminal 21A portion (the elliptical hole is provided in the center) is pressed, At this time, the TPS substrate 18 and the TPS wiring conductor 21 are pressed into contact with each other (hereinafter referred to as press-fit connection) by the force of the spring to achieve electrical conduction. Further, the connection terminal 21A on the side opposite to the connector of the TPS wiring conductor 21 is provided with a stopper 21B that prevents the TPS wiring conductor 21 from being disconnected from the wiring through hole 18D on the TPS substrate. By providing the connecting terminal 21A with an elastic shape, it is possible to protect against vibration resistance and shear stress due to resin flow during insert molding. Furthermore, by performing press-fit connection, it is not necessary to prepare a new metal conductor for connecting the TPS substrate 18 and the TPS wiring conductor 21, which leads to cost reduction. Furthermore, since the connection can be made at normal temperature without heating as in the case of soldering, it is not necessary to design in consideration of the thermal effect such as soldering, and an energy saving connection without using electric power can be realized.

  When the TPS wiring conductor 21 is connected to the TPS substrate 18 in the press-fit structure, the spring connection is always applied to the TPS substrate 18 because the mechanical connection is made by the spring force. Therefore, in order to disperse the force direction applied between the wiring through holes 18D of the adjacent TPS substrates 18, the fastening directions of the press-fit structure are set alternately one by one. As a result, the mechanical load on the TPS substrate 18 can be reduced, and it is not necessary to use an expensive high-strength substrate, leading to cost reduction. The connection terminal 22A on the side opposite to the connector of the motor wiring conductor 22 protrudes from the gear cover. As shown in FIG. 10, the resin molding portion 22A1 is interposed via the wiring conductor 22B protruding from the motor 2 side and the relay coupling 23. , 22B1 are electrically connected. Next, insert molding will be described.

FIG. 11 is an overall perspective view showing the assembled state of the TPS substrate 18, the TPS wiring conductor 21, and the motor wiring conductor 22. Insert molding is performed by setting each part in a mold in the state shown in FIG.
Since the ETB is installed in the engine room, it is placed in a high and low temperature environment. Therefore, polybutylene terephthalate (PBT) having good heat resistance and versatility is used as the resin used for exterior molding of the gear cover 20. (In this embodiment, the material of the gear cover is hereinafter referred to as PBT.) In order to set the components inexpensively, the PBT resin having good market distribution and good versatility should be used even in insert molding. Is desirable. As a result, there is no need to deteriorate the manufacturing tact due to the use of a special resin material or to design an expensive and complicated mold, and it is possible to manufacture at a low cost comprehensively. However, when insert molding including an electronic substrate is performed with a thermoplastic PBT material, high temperature and high pressure injection molding is performed, so the electronic components mounted on the upper surface of the substrate are subject to shear stress generated during heat and flow. There is a risk of damage.

  On the other hand, when the TPS substrate 18 is mounted in the resin, if the resin thickness covering the TPS substrate 18 is thick, the distance between the excitation conductor 17A of the rotor 17 and the excitation conductor 18A1 and the detection conductor 18A2 on the TPS substrate is increased accordingly. As a result, the function and accuracy of the inductance type rotation angle detection device cannot be achieved. Although it is possible to increase the inductance-type rotation angle detection device and increase the reception sensitivity, since the TPS substrate to be mounted becomes large, it is not possible to consolidate components in a compact manner. Therefore, it is necessary to reduce the resin thickness on the top surfaces of the excitation conductor 18A1 and the detection conductor 18A2 on the TPS substrate.

  However, if the thickness of the resin on the upper surfaces of the excitation conductor 18A1 and the detection conductor 18A2 is to be reduced, the resin flow deteriorates, and it is necessary to increase the resin molding pressure. However, when the resin molding pressure is increased, the electronic component may be damaged due to the resin pressure during molding.

  Therefore, in this example, by adjusting the molecular weight of the PBT resin to increase the fluidity, or by adding an additive, a molding resin made of a PBT resin material capable of low pressure molding and having high fluidity was obtained. . The selection of this resin is not limited to PBT resin. Various thermosetting or thermoplastic resins can be selected depending on the properties of the overmold resin forming the gear cover.

  In addition, if a PBT material containing a low melting point polymer material is used, it can be molded at a temperature lower than the resin molding temperature required at the time of normal resin molding, so it can be used for circuit components and solder joints resulting from the resin temperature. Thus, the entire circumference of the circuit board (excitation conductor 18A1, detection conductor 18A2, electronic circuit element 18B and wiring conductors 21, 22) can be insert-molded.

  FIG. 12 is a diagram illustrating a gate position when insert molding is performed.

  When insert molding is performed, in order to prevent distortion of the TPS substrate 18 due to the resin pressure, the gate position of the resin is set to the side gate position 24 </ b> A so that the resin flows parallel to the longitudinal direction of the TPS substrate 18. FIG. 12 shows one side of the TPS substrate 18 as a side gate position 24A as an example, but the same effect can be obtained by setting the other three sides. Since the side gate position 24A shown in FIG. 12 is close to the excitation conductor 18A1 and the detection conductor 18A2 on the TPS substrate, when a molding resin made of a PBT resin material capable of low pressure molding and having high fluidity is poured, A thin disk-like layer (resin film layer) 25 is easily formed on the portions of the excitation conductor 18A1 and the detection conductor 18A2. Then, the electronic circuit element 18B flows from both sides of the thin disk-shaped layer (resin film layer) 25 to the electrical junction 18C between the TPS substrate and the wiring conductor and the wiring conductors 21 and 22, and the motor relay terminal 24B Molding and finally reaching the connector terminal. Reference numeral 242 denotes a molding part of the electronic circuit element 18B, 244 denotes a molding part of the electrical joint 18C between the circuit board and the electrical conductor, 246 denotes a molding part of the wiring conductors 21 and 22 of the connector part, and 248 denotes connection terminals 22A and 22B of the motor. The molded part of each part is shown.

  In this embodiment, the excitation conductor 18A1 and the detection conductor 18A2, the electronic circuit element 18B, the electrical connection between the electronic circuit board and the wiring conductor, the wiring conductors 21 and 22 in the connector part, and the motor The connection terminal 22A portion is previously covered with resin by resin molding, and as a result, the electronic circuit board including the excitation conductor 18A1 and the detection conductor 18A2 and the wiring conductor (21, 22) are configured as one molded body. It is. As a result, when the motor-driven throttle valve device resin gear cover or inductance type rotation angle detection device is assembled on the automatic assembly line, there is no need to weld or solder the wiring conductor in the line. Will improve.

  In addition, the step of adhering the electronic circuit board to the resin gear cover is not necessary, and the assembly time can be shortened as much as the drying time of the adhesive is eliminated.

  Furthermore, since no adhesive is used, the dimensions of the mounting surface of the resin material gear cover to the throttle body 3 and the excitation conductor 18A1 and the detection conductor 18A2 can be accurately determined by resin molding.

  In other words, with an adhesive, there is a possibility that the dimension between the mounting surface of the electronic circuit board and the resin material gear cover varies from product to product depending on the amount. The variation varies depending on the dry state and is difficult to manage.

  In this embodiment, the resin material gear cover 20 is managed by managing the dimensions between the mounting surface of the resin material gear cover 20 on the throttle body 3 and the excitation conductor 18A1 and the detection conductor 18A2 by a jig during resin molding. Since the dimensions of the mounting surface of the throttle body 3 to the excitation conductor 18A1 and the detection conductor 18A2 can be the same for all products, the magnetic gap (detection gap) when combined with the rotor 17 can be the same for all products. . As a result, the magnetic performance as the inductance type rotation angle detection device does not vary depending on the product.

  Next, positioning of the insert molded product 24 during exterior molding (overmolding) will be described with reference to FIG.

  When performing insert molding (over mode) of the gear cover using the insert molded product 24 as an insert component, it is necessary to position the insert molded product 24 with the TPS substrate 18. In order to satisfy the sensing function, it is necessary that the rotor 17 and the through hole 18C opened in the central portion of the TPS substrate 18 be installed coaxially. Therefore, at the time of insert molding, a mold having the same diameter is put into the through hole 18C on the TPS substrate, and the flow of resin is blocked at that portion. As a result, a positioning hole 24B having the same diameter as the through hole 18C on the TPS substrate can be formed in the 24 insert molding products, and this hole can be used as a positioning hole at the time of exterior molding, thereby enabling easy and accurate positioning. Become. Thereby, an exterior molded article as shown in FIG. 13 is completed.

  In the present embodiment, the steps of insert molding (primary molding; also referred to as premold) and exterior molding (secondary molding; also referred to as overmold) have been described. However, the TPS substrate 18 and the TPS wiring conductor 21 It is also possible to manufacture the gear cover by a single molding after the motor wiring conductor 22 is in a partially assembled state.

  In this case, the exciting conductor 18A1, the detection conductor 18A2, the electronic circuit element 18B, the electrical connection portion of the TPS substrate and the wiring conductor, the TPS wiring conductor 21 and the motor wiring conductor 22 of the connector portion, and the motor connection terminal 22A portion are formed as a forming jig. And molded with a molding resin of a resin gear cover. As a result, the TPS substrate including the excitation conductor 18A1 and the detection conductor 18A2 and the wiring conductors (21, 22) are configured as one molded body. In the case of such a configuration, the assembling property is further improved because the molding process only needs to be performed once.

  Another embodiment will be described with reference to FIGS. 14, 15, and 16. FIG.

  FIG. 14 is an overall perspective view of the TPS substrate and wiring conductor assembly. FIG. 15 shows the shape after insert molding, and FIG. 16 is a general perspective view after exterior molding.

  Example 1 is an example in which the entire substrate is covered with a resin having good fluidity, and the resin thickness on the top surface of the excitation conductor 18A1 and the detection conductor 18A2 on the TPS substrate is molded thin, but insert molding is performed as shown in FIG. The same object can also be achieved by affixing a resin film 25A similar to the resin material used at the time of insert molding to the top surface of the exciting conductor 18 on the TPS substrate and performing the insert molding 24. The resin film 25A is made of the same material as that used in insert molding 24, so that deformation or cracking due to a difference in linear expansion coefficient or the like after molding can be prevented. Further, by attaching the resin film 25A that has escaped the portion of the positioning hole 24B used at the time of exterior molding, the center of the TPS substrate can be accurately positioned at the time of exterior molding.

  Another embodiment will be described with reference to FIG. 17, FIG. 18, and FIG.

  FIG. 17 is an overall perspective view of the insert-molded product 24 in which the entire TPS substrate is covered with a resin, FIG. 18 shows a shape after exterior molding (overmolding), and FIG. 19 is an upper surface of the excitation conductor 18A on the TPS substrate. It is the whole perspective view which made the resin thickness of the part thin by additional processing.

  In the present embodiment, the entire TPS substrate 18 is covered with a uniform resin thickness at the time of insert molding 24 of the excitation conductor 18A1 and the detection conductor 18A2 on the TPS substrate. As a result, the deformation of the substrate due to the shrinkage of the resin can be offset, and the deformation and distortion after molding are minimized. Then, after carrying out the exterior molding (overmolding), the resin portion covering the excitation conductor 18A1 and the detection conductor 18A2 is cut by cutting to a position (depth) where the TPS substrate 18 and the rotor 17 do not contact to bring them close together, Satisfy the sensing detection function. The additional machining range is machined with a diameter larger than that of the rotor 17.

  Instead of cutting, it is also possible to heat and soften the insert molded product during exterior molding, and press the resin portion covering the excitation conductor 18A1 and the detection conductor 18A2 in that state to make it thinner. With this method, there is an effect that it is unnecessary to remove the cutting powder.

  Another embodiment will be described with reference to FIGS.

  In the present embodiment, only the periphery of the TPS substrate is made of resin material at the time of insert molding so that the resin does not cover the electronic components mounted on the TPS substrate 18 and the excitation conductor 18A1 and the detection conductor 18A2 on the TPS substrate. A layer 24C on the picture frame covered by is provided. According to the present embodiment configured as described above, the excitation conductor 18A1 and the detection conductor 18A2 are exposed, so that when combined with the rotor 17, the detection gap between the excitation conductor 17A can be further reduced and the detection of TPS can be performed. Accuracy is improved. Here, in this embodiment, molding resin may overflow from the back side of the TPS substrate 18 to the front side through the through hole 18F during insert molding. This overflowing molding resin is mixed in each through hole 18F, and as a result, there is a possibility that the detection gap between the rotor side conductor and the conductor cannot be reduced. Therefore, as shown in FIG. 23, as an improvement, a resin film 25A is pasted on the back side of the TPS substrate 18, and then the resin is molded into a frame shape. In this way, the above-mentioned problem can be solved without the molding resin overflowing from the back side of the TPS substrate 18 through the through hole 18F to the front side.

  FIG. 20 is an enlarged perspective view of the TPS substrate, and FIG. 21 is an overall perspective view showing the back surface of the TPS substrate and the wiring conductor. The above technique will be described in more detail.

  As shown in FIG. 20, the TPS substrate 18 has a through hole 18F. When the resin flows into this gap and is cured after molding, it may cause cracks due to the difference in the linear expansion coefficient between the TPS substrate 18 and the resin that has entered the through hole 18F. In order to prevent this, as shown in FIG. 21, before insert molding, a resin film 25A similar to the material used at the time of insert molding is pasted on the TPS substrate back surface 18E side so that the through hole 18F is hidden, and insert molding is performed. The resin is blocked from entering the through hole 18F at 24:00.

  FIG. 22 is an overall perspective view in which the outer periphery of the TPS substrate is insert-molded, FIG. 23 is a cross-sectional view of the TPS substrate portion of FIG. 22, and FIG. 24 is an enlarged view thereof.

  When insert molding is performed only on one side of the TPS substrate 18, materials having different linear expansion coefficients are integrally molded. Therefore, deformation and warpage occur after molding shrinkage, resulting in residual stress, which causes resin cracking. In order to suppress this, as shown in FIG. 25, the outer periphery of the TPS substrate 18 is covered with resin, and the resin thickness 24E on the lower surface of the TPS substrate is set to a resin thickness 24E on the upper surface of the TPS substrate. Set as. By doing so, it becomes possible to cancel the resin shrinkage between the upper surface and the lower surface of the substrate after molding, and this is a measure for preventing deformation and warping. Further, in order to prevent the generation of burrs on the upper surface of the TPS substrate 18 after the insert molding, the range of the frame insert molding 24C surrounding the outer periphery of the TPS substrate 18 is a position where an electronic component mounted on the upper surface of the substrate is avoided and a sensing unit on the upper surface of the TPS substrate Avoiding the position, molding is performed by setting a range 24F where the TPS substrate 18 and the frame insert molding 24C overlap.

  Another embodiment will be described with reference to FIGS.

  In this embodiment, by using a foamable resin for the insert molded product 26, residual stress due to deformation and warping after molding shrinkage is reduced, and resin cracking is suppressed.

  A layer on the frame that covers only the periphery of the TPS substrate with a resin material at the time of insert molding so that the resin does not cover the electronic components mounted on the TPS substrate 18 and the excitation conductor 18A1 and the detection conductor 18A2 on the TPS substrate. 24C is provided. According to the present embodiment configured as described above, the excitation conductor 18A1 and the detection conductor 18A2 are exposed, so that when combined with the rotor 17, the detection gap between the excitation conductor 17A can be further reduced and the detection of TPS can be performed. Accuracy is improved.

  On the TPS substrate 18, there are a wiring through hole 18 </ b> D responsible for external electrical connection and an application specific integrated circuit ASIC 18 </ b> B. If a foreign substance such as abrasion powder or a droplet due to condensation is applied to these, there is a possibility of short-circuiting, so that they are covered with a foaming resin during insert molding. Since the foamable resin encloses a fine bubble-like gas between the solid resins, the impact mitigation effect, vibration damping, thermal insulation, and electrical insulation are improved compared to the resin alone. It is an excellent material for covering parts.

  Here, in this embodiment, as in the fourth embodiment, the molding resin may overflow from the back side to the front side of the TPS substrate 18 through the through hole 18F during insert molding. Resin molding to frame shape after sticking. Further, as shown in FIG. 25, the outer periphery of the TPS substrate 18 is covered with resin, and a thickness equivalent to the resin thickness 24D on the lower surface of the TPS substrate set on the lower surface side of the TPS substrate is set as the resin thickness 24E on the upper surface of the TPS substrate. By doing so, it becomes possible to cancel the resin shrinkage between the upper surface and the lower surface of the substrate after molding, and this is a measure for preventing deformation and warping.

  FIG. 27 is an overall perspective view in which the outer periphery of an insert molded product using a foamable resin is overmolded.

  The aspects of the above embodiment are summarized as follows.

<Embodiment 1>
In an electronically controlled throttle body that is feedback controlled by an actuator and a position sensor,
A case member that covers the rotation detection body and has a substrate attached thereto,
An exciting conductor portion that is annularly disposed on the substrate and generates a magnetic field by applying a current,
An excitation conductor portion that is fixed to the rotation detection body and is arranged in a non-contact state with a space from the excitation coil portion, and generates an electric current according to a rotation position of the rotation detection body by electromagnetic action,
A receiving conductor portion that is disposed on the substrate and generates a current corresponding to a current flowing through the excitation conductor;
A gear provided between the motor and throttle valve to decelerate the motor power,
A rotation angle detection device comprising a shaft that functions as a rotation axis of the gear,
The substrate and the terminal disposed in the case are electrically coupled in advance before molding the case member,
A throttle valve device, wherein the substrate and the terminal are covered with a member forming a case.

<Embodiment 2>
In what is described in Embodiment 1,
A throttle valve device characterized in that the central portion of the rotation detecting portion on the substrate is not covered with resin.

<Embodiment 3>
In what is described in Embodiment 1,
A throttle valve device, wherein the substrate and a terminal having an elastic shape at the other end disposed in the case are electrically connected in advance by press-fit connection before molding of the case member. .

<Embodiment 4>
In what is described in Embodiments 2 and 3,
The throttle valve device, wherein the substrate and the terminal are mounted by molding at least once.

<Embodiment 5>
In what is described in Embodiments 1 and 4,
A throttle valve device characterized in that the entire circumference of the substrate is covered with a case member.

<Embodiment 6>
In what is described in Embodiment 5,
A throttle valve device characterized in that the resin thickness in the rotation detecting portion range on the substrate is thinner than the resin thickness of other case materials.

<Embodiment 7>
In what is described in Embodiment 4,
A throttle valve device characterized in that the rotation detection unit range on the substrate and a range excluding a part where electronic parts are mounted are covered with resin.

<Embodiment 8>
In what is described in Embodiment 7,
A diaphragm characterized in that a resin film similar to that of the case member is attached to the back surface of the substrate covered with the case member opposite to the electronic components and excitation conductors mounted on the upper surface of the substrate before molding. Valve device.

  As described above, according to the present invention, the inductance between the conductor attached to the rotating shaft of the rotating body and the coil conductor attached to the stator facing the rotor changes according to the positional relationship between the two. The present invention relates to a rotation angle detection device that detects a rotation position or a rotation angle of a rotating body by detecting a rotation position of a rotating conductor in a non-contact manner.

  A motor-driven throttle valve device that electrically controls an opening area of an air passage of an internal combustion engine with a throttle valve driven by a motor, the rotation angle detection described above for detecting the rotation angle of the throttle valve It relates to the one equipped with the device.

  Furthermore, the present invention relates to a technique for integrally molding a mounting board as a stator on which a coil is mounted with a conductor and a signal processing circuit together with a wiring conductor to the outside.

  More specifically, a part of the mounting substrate including the connection terminal portion and a part of the wiring conductor to the outside are molded as a first molded body, and the molding is further overmolded with a resin to form a second molded body. It is related with what constitutes.

  More specifically, the present invention relates to a variable-ductive non-contact rotational angle detection device that detects a rotational angle of a rotary shaft of a throttle valve used in a motor-driven intake air amount control valve (throttle valve).

  In the rotation angle detection device of the present invention, the resin cover includes a circuit board on which the fixed conductor and the electronic circuit are mounted, a connector for electrically connecting to an external device, a connector terminal formed on the connector, and a circuit board. And at least a part of the circuit board and at least a part of the electrical conductor are formed as one molded body formed of the same resin, the resin is foamed It is made of a functional resin.

  Preferably, the fixed-side conductor and the electric conductor fixed to the circuit board are configured as one first molded body that is coated and molded with the same foamable resin, and the first molded body is formed of a resin resin for the resin cover. Furthermore, it is overmolded to form a second molded body.

  Preferably, the electrical connection portion between the circuit board and the electric conductor is coated with a foamed resin molding.

  Preferably, the resin layer covering the fixed conductor is formed thinner than the resin layer covering the electric conductor.

  Preferably, the electrical connection portion between the circuit board and the electrical conductor is connected by press contact (press fit).

  Specifically, it is a motor-driven throttle valve control device provided with an inductance-type non-contact type rotational angle detection device having the above-mentioned characteristics, wherein the relay terminal for supplying power to the motor is the same as the resin resin of the resin cover The electric conductor for supplying power to the motor is formed as a single molded body together with the circuit board and other electric conductors.

  Preferably, the resin cover functions as a container that houses a gear mechanism that transmits the rotation of the motor to the throttle valve.

  Preferably, the rotation side conductor is attached to a throttle valve shaft or a throttle gear fixed to the throttle valve shaft.

  According to the present invention, since it is not necessary to bond the circuit board to the resin cover, the board is distorted or cracked when the gear cover is molded with the resin without losing the effect of reducing the number of assembly steps without reducing accuracy. The possibility of entering can be reduced.

  Further, by using the rotation angle detection device according to the present invention, the control accuracy of the motor-driven throttle valve is improved and the manufacturing yield is improved.

  In the embodiment, the inductance-type non-contact type rotation angle detection device and the throttle valve device driven by the motor of the internal combustion engine equipped with the inductance-type non-contact rotation angle detection device have been described. However, the present invention mounts a circuit board having electronic components on the cover member. It can be applied to all devices.

  It can also be applied to a motor-driven throttle device for an internal combustion engine having two default mechanisms.

  In addition, this invention is not limited to an above-described Example, Various modifications are included. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. Further, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Further, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

DESCRIPTION OF SYMBOLS 1 Bore 2 Motor 2A Motor housing 2B Terminal on motor 3 Throttle body 4 Throttle shaft 5, 6 Needle bearing 7 Thrust retainer 8 Throttle valve 9, 12 Screw 10 Throttle gear 10A Throttle gear metal plate 10B Throttle gear 11 Nut 13 Motor gear 14 Intermediate gear shaft 15 Intermediate gear 15A Large diameter gear portion 15B Small diameter gear portion 15C Intermediate gear boss portion 16 Return spring 17 Rotor 17A Excitation conductor 17B Positioning through hole 18 TPS board 18A1 Excitation conductor 18A2 Detection conductor 18C Through hole 18D Wiring through Hole 18E TPS substrate back surface 18F Through hole 19 Rotor holder 19A Rotor holder inserter 19B Positioning projection 19C Annular window hole 20 Gear cover 20A Positioning protrusion 20B Connector 20C Intermediate gear boss 20D Intermediate gear boss 21 TPS wiring conductor 21A, 22A Connection terminal 21B Stop prevention stopper 22 Motor wiring connection 23 Relay coupling 24 Insert molded product 24A Side gate position 24B Positioning hole 24C Frame-shaped layer 24D TPS substrate lower surface resin thickness 24E TPS substrate upper surface resin thickness 24F TPS substrate and resin overlap area 25 Layer on disk (resin film layer)
25A Resin film 26 Additional sensing area

Claims (8)

A rotating side conductor attached to the rotating shaft of the rotating body;
A fixed-side conductor attached to the resin cover member facing this;
An electronic circuit for detecting the rotational position of the rotating body by utilizing the fact that the inductance between the two conductors changes according to the positional relationship in the rotational direction of both, and a rotation angle detecting device comprising:
The resin cover is
A circuit board on which the fixed-side conductor and the signal processing circuit are mounted, a connector for electrically connecting to an external device, a connector terminal formed on the connector, and an electric conductor for connecting the circuit board;
An inductance-type non-contact rotation angle detection device configured as one molded body in which at least a part of the circuit board and the electric conductor are molded from the same foamable resin. What is claimed in claim 1
The fixed-side conductor and the electric conductor fixed to the circuit board are configured as a single molded body formed by coating with the same resin,
An inductance-type non-contact rotation angle detecting device, wherein the molded body is further overmolded with a molding resin of the resin cover having the connector. In one of claims 1 and 2,
An inductance-type non-contact rotation angle detection device in which an electrical connection portion between the circuit board and the electric conductor is coated and formed with the same resin as the molded body or the resin cover. What is described in claim 3,
An inductance-type non-contact rotation angle detecting device, wherein a thickness of a resin layer covering the fixed conductor is smaller than a thickness of a resin layer covering the electric conductor. In any one of claims 1 to 4,
An inductance-type non-contact rotation angle detection device in which an electrical connection portion between the circuit board and the electric conductor is connected by press contact. In the motor-driven throttle valve control device provided with the inductance-type non-contact rotation angle detection device according to any one of claims 1 to 5,
The relay terminal for power supply to the motor is molded with the same molding resin as the molding resin of the resin cover, and the electrical conductor for power supply to the motor is molded together with the circuit board and other electrical conductors. A motor-driven throttle valve control device configured as a body. The thing of Claim 6 WHEREIN:
The motor-driven throttle valve control device, wherein the resin cover functions as a housing body that houses a gear mechanism that transmits rotation of the motor to the throttle valve. The thing of Claim 6 WHEREIN:
A motor-driven throttle valve control device in which the rotary conductor is attached to the throttle valve shaft or a throttle gear fixed to the throttle valve shaft.