Throttle device sensor unit

Abstract

To provide a sensor unit of a throttle device that is reducible in cost by simplifying manufacturing processes while preventing trouble such as breakage of an electronic component on a circuit board due to heat and pressure in injection molding of a casing.SOLUTION: A sensor unit 10 of a throttle device 1 comprises: a circuit board 12 connected to sensors 8, 13, and 14 detecting a state of intake air circulating in a throttle bore 2a of the throttle device 1; a casing 11 manufactured through injection molding of a synthetic resin material by using the circuit board 12 as an insert article; protection members 15, 16 embedded as insert articles together with the circuit board 12 in the injection molding of the casing 11; and a recessed storage part 15 which is formed integrally in the protection member 15 to be open to the side of the circuit board 12, and accommodates a region, including an electronic component etc., on the circuit board 12, inside with its opening end in contact with a part on the circuit board 12.SELECTED DRAWING: Figure 7

Description

Technical Field

[0004] , , , ,

[0003]

[0001] The present invention relates to a sensor unit of a throttle device.

Background Art

[0002] As a sensor unit of a throttle device, there is one in which a casing provided with a circuit board is attached to the throttle device, and signals regarding the state of intake air detected by various sensors are output to an external device via this circuit board. The casing is manufactured by injection molding a synthetic resin material from the viewpoint of productivity and the like, and in this case, the circuit board may be embedded in the casing as an insert part. However, the circuit board at this time may be warped due to the heat and pressure of the molten resin, and due to the warping of the circuit board, the electronic components mounted on the circuit board may be damaged or the soldering portions may be peeled off. In addition, since the molten resin also contacts the electronic components and soldering portions on the circuit board, there are cases where its heat and pressure directly act on the electronic components to damage them, or directly act on the soldering portions to peel them off.

[0003] As a countermeasure, for example, Patent Document 1 discloses a technique that combines injection molding and mold filling for manufacturing a casing. The sensor unit of Patent Document 1 manufactures a casing having a recess by injection molding, disposes a circuit board in the recess, and then injects and cures a sealing resin by mold filling to seal the circuit board.

[0004] ​​​[Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2021-113517 [Overview of the project] [Problems that the invention aims to solve]

[0006] However, the technology described in Patent Document 1 requires that after the casing is injection molded, the circuit board be placed in the recess and sealed by mold filling. As a result, although problems such as damage to electronic components and delamination of solder joints can be prevented, the number of steps increases due to the mold filling process compared to, for example, insert molding of the circuit board, leaving room for improvement in terms of manufacturing costs.

[0007] The present invention was made to solve these problems, and its objective is to provide a sensor unit for a throttle device that can prevent problems such as warping of the circuit board due to the heat and pressure of the molten resin when the casing is injection molded, and consequently damage to electronic components mounted on the circuit board and delamination of solder joints, while also simplifying the manufacturing process and reducing manufacturing costs. [Means for solving the problem]

[0008] To achieve the above objective, the throttle device sensor unit of the present invention is a sensor unit for a throttle device that adjusts the intake air of an engine, and comprises: a circuit board connected to a sensor that detects the state of the intake air flowing through the throttle bore of the throttle device and outputs a signal from the sensor to the outside; a casing manufactured by injection molding a synthetic resin material with the circuit board as an insert; first and second protective members embedded together with the circuit board as an insert during injection molding of the casing and arranged on both sides of the circuit board, each abutting against the circuit board; and a recessed housing portion integrally formed on at least one of the first and second protective members, having a shape that opens towards the circuit board, with the opening end abutting against the circuit board to house a predetermined area on the circuit board inside and isolate it from the outside. At least one of the first and second protective members has an opening that exposes the soldering points on the circuit board to the outside. It is characterized by the following: Furthermore, the throttle device sensor unit, which is attached to a throttle device that adjusts the intake air of an engine, comprises a circuit board connected to a sensor that detects the state of intake air flowing through the throttle bore of the throttle device and outputs a signal from the sensor to the outside; a casing manufactured by injection molding a synthetic resin material with the circuit board as an insert; first and second protective members embedded together with the circuit board as an insert during injection molding of the casing and arranged on both sides of the circuit board, each abutting against the circuit board; and a recessed housing portion integrally formed with at least one of the first and second protective members, having a shape that opens towards the circuit board, with the opening end abutting against the circuit board to house a predetermined area on the circuit board and isolate it from the outside, wherein at least one of the first and second protective members has a notch formed therein that exposes the circuit board to the outside, and molten resin from the injection molding of the casing flows into the notch and becomes integrated. Furthermore, in a throttle device sensor unit attached to a throttle device that adjusts the intake air of an engine, the sensor unit comprises a circuit board connected to a sensor that detects the state of the intake air flowing through the throttle bore of the throttle device and outputs a signal from the sensor to the outside, a casing manufactured by injection molding a synthetic resin material with the circuit board as an insert, and first and second protective members embedded together with the circuit board as inserts during the injection molding of the casing, arranged on both sides of the circuit board and in contact with the circuit board, respectively, and the first and The first and second protective members are each integrally formed with terminal displacement restricting portions, the terminal displacement restricting portions sandwich the connector terminals from both sides and position them in the thickness direction of the circuit board. Furthermore, the throttle device sensor unit, which is attached to a throttle device that adjusts the intake air of an engine, comprises a circuit board connected to a sensor that detects the state of intake air flowing through the throttle bore of the throttle device and outputs a signal from the sensor to the outside; a casing manufactured by injection molding a synthetic resin material with the circuit board as an insert; first and second protective members embedded together with the circuit board as an insert during injection molding of the casing and arranged on both sides of the circuit board, each abutting against the circuit board; and a recessed housing portion integrally formed on at least one of the first and second protective members, having a shape that opens towards the circuit board, with the opening end abutting against the circuit board to house a predetermined area on the circuit board and isolate it from the outside, wherein at least one of the first and second protective members has a sensor displacement restricting portion integrally formed thereon, and the sensor displacement restricting portion abuts against the sensor and is positioned in the thickness direction of the circuit board.

[0009] In other embodiments, the concave housing may house an area that corresponds to substantially the entire surface of the circuit board as a predetermined region.

[0010] In other embodiments, the concave housing may contain a predetermined region that includes electronic components mounted on a circuit board.

[0011] In other embodiments, the recessed housing portion may house a predetermined area, including a soldering point on the circuit board.

[0012] In other embodiments, the recessed housing portions may be provided corresponding to multiple regions on the circuit board, and each of the multiple regions may be individually housed inside. In other embodiments, the concave housing may be filled with an elastic cushioning material.

[0016] As another aspect, the circuit board has connector terminals that constitute a connector for connecting to a device that is an output destination of a signal from the sensor, the first or second protective member is manufactured by injection molding a synthetic resin material, and a part of the connector terminal is embedded as an insert during the injection molding of the first or second protective member, and the base end may be soldered to the circuit board.

[0019] As another aspect, the first and second protective members may be made of a synthetic resin material that has both higher heat resistance and rigidity than the material of the circuit board.

Advantages of the Invention

[0025] According to the sensor unit of the throttle device of the present invention, warping of the circuit board caused by the heat and pressure of the molten resin during injection molding of the casing, and thus troubles such as damage to the electronic components mounted on the circuit board and peeling of the soldering points can be prevented, and the manufacturing process can be simplified and the manufacturing cost can be reduced.

Brief Description of the Drawings

[0026] [Figure 1] It is a perspective view showing a state where the sensor unit of the embodiment is attached to the throttle device. [Figure 2] It is an exploded perspective view showing a state where the sensor unit is removed from the throttle device. [Figure 3] It is a cross-sectional view taken along line III-III of FIG. 1. [Figure 4] It is a perspective view showing a single sensor unit. [Figure 5] It is a perspective view showing the sensor unit with the casing omitted from FIG. 4. [Figure 6] It is a perspective view showing the sensor unit viewed from the side opposite to FIG. 5. [Figure 7] It is an exploded perspective view corresponding to FIG. 5 showing the relationship between the circuit board and the left and right protective members. [Figure 8]It is an exploded perspective view corresponding to FIG. 6 showing the relationship between the circuit board and the left and right protective members. [Figure 9] It is a cross-sectional view showing the circuit board and the left protective member. [Figure 10] It is a cross-sectional perspective view taken along the line X-X of FIG. 9. [Figure 11] It is a cross-sectional perspective view taken along the line XI-XI of FIG. 9. [Figure 12] It is a cross-sectional perspective view taken along the line XII-XII of FIG. 9. [Figure 13] It is a cross-sectional perspective view taken along the line XIII-XIII of FIG. 9. [Figure 14] It is a cross-sectional perspective view taken along the line XIV-XIV of FIG. 9. [Figure 15] It is a cross-sectional perspective view taken along the line XV-XV of FIG. 9. [Figure 16] It is a cross-sectional view taken along the line XVI-XVI of FIG. 9. [Figure 17] It is a cross-sectional view taken along the line XVII-XVII of FIG. 9. [Figure 18] It is an exploded perspective view corresponding to FIG. 8 showing a sensor unit of Alternative Example 1 in which the right protective member and the circuit board are positioned via fitting pins and fitting holes. [Figure 19] It is a perspective view corresponding to FIG. 6 showing a sensor unit of Alternative Example 2 in which the soldering portion of the connector terminal is exposed to the outside. [Figure 20] It is a perspective view showing the right protective member of a sensor unit of Alternative Example 3 in which three cutouts are formed on the outer periphery of the right base portion. [Figure 21] It is a front view showing a sensor unit of Alternative Example 3 after molding the casing in the same way. [Figure 22] It is a partial cross-sectional view showing a sensor unit of Alternative Example 4 in which a buffer material having elasticity is filled in the concave accommodating portion of the left protective member. [Figure 23] It is a perspective view corresponding to FIG. 6 showing a sensor unit of Alternative Example 5 in which the circuit board is sealed by fitting the ridges and grooves formed around the left and right protective members. [Figure 24] It is a cross-sectional perspective view corresponding to FIG. 14 showing the sensor unit of Alternative Example 5 in the same way. [Figure 25] This is an exploded perspective view corresponding to Figure 8, showing a sensor unit of another example 6 equipped with a card edge connector. [Figure 26] This is a cross-sectional view corresponding to Figure 16, which also shows the sensor unit of another example 6. [Modes for carrying out the invention]

[0027] The following describes one embodiment of a sensor unit for a throttle device that embodies the present invention. Figure 1 is a perspective view showing the sensor unit of this embodiment mounted on the throttle device, Figure 2 is an exploded perspective view showing the sensor unit removed from the throttle device, Figure 3 is a cross-sectional view taken along line III-III in Figure 1, and Figure 4 is a perspective view showing the sensor unit alone.

[0028] 《Throttle device》 The throttle device 1 of this embodiment is installed on a single-cylinder engine for a motorized bicycle, and the configuration of the throttle device 1 will be described first. The throttle body 2 of the throttle device 1 has a single throttle bore 2a formed through it, which communicates with the inside of the engine cylinder (not shown). Intake air from an air cleaner (not shown) flows through the throttle bore 2a and is supplied to the inside of the engine cylinder. A throttle valve 3 is supported inside the throttle bore 2a by a throttle shaft 4 so as to be able to open and close, and a wire drum 5 is attached to one end of the throttle shaft 4. The throttle grip of the vehicle is connected to the wire drum 5 via a throttle wire (not shown). In conjunction with the operation of the throttle grip, the throttle shaft 4 rotates together with the wire drum 5, opening and closing the throttle valve 3, thereby adjusting the amount of intake air to the engine. Here, the throttle valve 3 is biased in the closing direction by a return spring 6. Note that 7 in Figure 3 is an idle speed control valve (ISCV) that controls the idle rotation speed of the engine.

[0029] For the sake of explanation, the axial direction along the throttle shaft 4 shown in Figure 1 will be referred to as the left-right direction, the direction of intake air flow along the throttle bore 2a will be referred to as the front-rear direction, and the direction perpendicular to these will be referred to as the up-down direction.

[0030] As shown in Figure 3, the left side of the throttle shaft 4 protrudes from the throttle body 2, and the excitation conductor 8a of the inductive throttle opening sensor 8 is fixed to its end. A circular recess 2b is formed on the left side of the throttle body 2, opening to the left with the throttle shaft 4 as the center, and a mounting surface 2c is formed around the circular recess 2b. The sensor unit 10 is attached to the left side of the throttle body 2 via these circular recess 2b and mounting surface 2c.

[0031] Circuit board Next, the configuration of each part of the sensor unit 10 will be explained in order. Figure 5 is a perspective view of the sensor unit 10 with the casing omitted from Figure 4, Figure 6 is a perspective view of the sensor unit 10 viewed from the opposite side of Figure 5, Figure 7 is an exploded perspective view corresponding to Figure 5 showing the relationship between the circuit board and the left and right protective members, and Figure 8 is an exploded perspective view corresponding to Figure 6 showing the relationship between the circuit board and the left and right protective members.

[0032] As shown in Figures 4-6, the casing 11 of the sensor unit 10 is made by injection molding of a synthetic resin material. During injection molding, the left and right protective members 15 and 16 are embedded in the casing 11 as inserts along with the circuit board 12 and the sensors 8, 13, and 14. In this embodiment, the casing 11 is molded into the desired shape in a single injection molding. The left protective member 15 corresponds to the "second protective member" of the present invention, and the right protective member 16 corresponds to the "first protective member" of the present invention.

[0033] As shown in Figures 5-8, the circuit board 12 is positioned facing left and right, and wiring patterns 12a are formed on both sides. IC 17 and various electronic components (not shown) are mounted on the left side of the circuit board 12, and the excitation conductor 8b and signal detection conductor 8c of the throttle opening sensor 8 are formed there.

[0034] On the upper front right side of the circuit board 12, the base ends of the two terminals 13b of the intake air temperature sensor 13 are soldered, and each terminal 13b extends to the right, with the sensor body 13a attached to its tip. Also, on the upper rear right side of the circuit board 12, the three terminals 14b of the sensor body 14a of the intake pressure sensor 14 are soldered. Subsequently, 13c is attached to the soldering points of the intake air temperature sensor 13 and the intake pressure sensor 14.

[0035] The base ends of five connector terminals 18, arranged in a vertical line, are soldered to the front edge of the circuit board 12, and each is connected to a wiring pattern 12a on the circuit board 12. Each connector terminal 18 is bent at a right angle and extends forward, and as will be described in detail later, the bent portion is embedded in the right protective member 16. Hereafter, 18a will be attached to the soldered portion of the connector terminal 18.

[0036] 《Casing 11 of sensor unit 10》 The circuit board 12 described above is used as an insert in the injection molding of the casing 11 of the sensor unit 10, and the casing 11 is mounted on the throttle device 1. As shown in Figures 3 and 4, a circular cylindrical portion 11a is integrally formed on the right side of the casing 11, and a mounting surface 11b is formed around the circular cylindrical portion 11a. A pair of bolt holes 11c are provided through the casing 11, and the casing 11 is fastened to the throttle body 2 by bolts 20 inserted through these bolt holes 11c. In this mounted state of the casing 11, as shown in Figure 3, the circular cylindrical portion 11a of the casing 11 fits into the circular recess 2b of the throttle body 2, and the mounting surface 11b of the casing 11 is superimposed on the mounting surface 2c of the throttle body 2. The excitation conductor 8a of the throttle opening sensor 8 is arranged inside the circular cylindrical portion 11a and faces the excitation conductor 8b and signal detection conductor 8c on the circuit board 12.

[0037] The detection principle of the inductive throttle position sensor 8 is well known, so we will not explain it in detail, but when a magnetic field is generated in the excitation conductor 8b, eddy currents flow in the excitation conductor 8a in response. When the excitation conductor 8a rotates together with the throttle shaft 4, the inductance of the excitation conductor 8b changes due to mutual induction, which is detected by the signal detection conductor 8c and converted into a signal correlated with the throttle position by IC 17.

[0038] Furthermore, as shown in Figures 4, 5, and 7, a detector 16c, integrally formed with the right protective member 16, protrudes to the right from the mounting surface 11b of the casing 11. As will be described in detail later, the sensor body 13a and terminals 13b of the intake air temperature sensor 13 are housed inside the hollow detector 16c. When the casing 11 is mounted on the throttle body 2, the tip of the detector 16c is exposed inside the throttle bore 2a, and the intake air temperature is detected by the intake air temperature sensor 13.

[0039] Furthermore, as shown in Figure 4, a communication chamber 11d is formed at the mounting surface 11b of the casing 11, and, as will be described in detail later, the pressure case portion 16d of the intake pressure sensor 14 formed on the right protective member 16 is exposed inside the communication chamber 11d. When the casing 11 is mounted on the throttle body 2, the communication chamber 11d communicates with the inside of the throttle bore 2a via a communication passage (not shown) formed in the throttle body 2, and the intake pressure acts inside the pressure case portion 16d via the communication passage and the communication chamber 11d, and the intake pressure is detected by the sensor body 14a.

[0040] As shown in Figures 4 and 5, the casing 11 has an opening formed in the front, which is a connector cylindrical portion 21a. Connector terminals 18 are arranged inside this connector cylindrical portion 21a to form the connector 21.

[0041] 《Protective components 15, 16》 As shown in Figures 7 and 8, a left protective member 15 is provided on the left side of the circuit board 12, and a right protective member 16 is provided on the right side. Each protective member 15 and 16 is made of a synthetic resin material that has higher heat resistance and rigidity than the material of the circuit board 12, and is designed to maintain its intended shape without deformation even when subjected to the heat and pressure of the molten resin during insert molding into the casing 11. As shown in Figures 5 and 6, the circuit board 12 is insert molded while sandwiched between these protective members 15 and 16 and embedded in the casing 11.

[0042] <Right protective component 16> Figure 9 is a cross-sectional view showing the circuit board 12 and the left protective member 15, Figure 10 is a perspective view of the cross-section along line XX in Figure 9, Figure 11 is a perspective view of the cross-section along line XI-XI in Figure 9, Figure 12 is a perspective view of the cross-section along line XII-XII in Figure 9, Figure 13 is a perspective view of the cross-section along line XIII-XIII in Figure 9, Figure 14 is a perspective view of the cross-section along line XIV-XIV in Figure 9, Figure 15 is a perspective view of the cross-section along line XV-XV in Figure 9, Figure 16 is a cross-sectional view along line XVI-XVI in Figure 9, and Figure 17 is a cross-sectional view along line XVII-XVII in Figure 9.

[0043] As shown in Figures 7, 8, 16, and 17, the right protective member 16 consists of a flat right base portion 16a facing left and right, a terminal insert portion 16b integrally formed on the front side of the right base portion 16a, a detector 16c integrally formed on the upper side of the terminal insert portion 16b, and a pressure case portion 16d integrally formed on the upper diagonal rear side of the right base portion 16a.

[0044] When viewed from the right, the right base portion 16a has a shape that corresponds to almost the entire right surface of the circuit board 12, excluding the soldering points 18a of each connector terminal 18 and the intake air temperature sensor 13, and is superimposed on this area. Although a wiring pattern 12a is formed on this area, no electronic components are mounted and it remains flat. As a result, the right surface of the circuit board 12 is isolated from the outside by the contact of the right base portion 16a, preventing molten resin from entering between the two members 12 and 16a during the injection molding of the casing 11, which will be described later. In addition, four locations around the right base portion 16a protrude outwards, and fitting holes 16e are provided through each of them.

[0045] The terminal insert portion 16b is a rectangular parallelepiped extending vertically in front of the right base portion 16a, and the right-angle bent portions of each connector terminal 18 are embedded inside. These right-angle bent portions correspond to the "part of the connector terminal" of the present invention. The tip of each connector terminal 18 protrudes forward from the terminal insert portion 16b and is arranged inside the connector cylinder portion 21a as described above, and its base end is soldered to the circuit board 12. Five right-side mold contact pins 16f are arranged in a vertical row on the right side of the terminal insert portion 16b and protrude to the right. When the mold is closed during injection molding of the casing 11, which will be described later, the right end of each right-side mold contact pin 16f is pressed by the inner wall of the right-side mold.

[0046] The detector 16c protrudes to the right from the right protective member 16, and its hollow interior is a concave housing portion 16g. The concave housing portion 16g opens toward the circuit board 12 side, housing the intake air temperature sensor 13 inside, and the opening end is in contact with the circuit board 12, thereby isolating the intake air temperature sensor 13 from the outside.

[0047] The pressure case portion 16d is positioned in a location corresponding to the sensor body 14a of the intake pressure sensor 14, and is in contact with the sensor body 14a from the right. A communication hole 16h is provided through the center of the pressure case portion 16d, and the sensor body 14a and the communication chamber 11d of the casing 11 are in communication through this communication hole 16h.

[0048] <Left protective component 15> As shown in Figures 7, 9, and 16, the left protective member 15 consists of a left base portion 15a which is flat and faces left and right, five pin bodies 15b which are integrally formed on the front side of the left base portion 15a, and a sensor retaining portion 15c which is integrally formed on the upper diagonal rear side of the left base portion 15a.

[0049] The left base portion 15a is formed by dividing the top portion 15d, which corresponds to the left side of the circuit board 12, into a plurality of recessed housing portions 15f by a partition wall 15e. Specifically, the top portion 15d has a shape that corresponds to the entire left side of the circuit board 12 and is positioned spaced to the left of the circuit board 12, with a partition wall 15e integrally formed on the right side of the top portion 15d. The partition wall 15e forms an annular shape that surrounds the outer circumference of the top portion 15d and, inside, forms a grid that divides the top portion 15d into a plurality of recessed housing portions 15f. As a result, each recessed housing portion 15f has a shape that opens towards the circuit board 12, and the entire left side of the circuit board 12 is covered by these recessed housing portions 15f.

[0050] Each recessed housing portion 15f has an open end that abuts against the left side surface of the circuit board 12, and each corresponding area on the left side surface is individually housed inside, thereby isolating each area from the outside. Electronic components such as IC 17 may be mounted within each area, and there may also be soldering points 18a, 13c, and 14c for connector terminals 18, intake air temperature sensor 13, and intake pressure sensor 14. Such electronic components and soldering points 18a, 13c, and 14c are also housed within the recessed housing portion 15f along with the area on the left side surface, and are isolated from the outside. In this example, five recessed housing portions 15f are formed, but this can be arbitrarily changed depending on the arrangement of electronic components, etc. These recessed housing portions 15f and the recessed housing portion 16g of the right protective member 16 described above correspond to the "recessed housing portion" of the present invention. Furthermore, electronic components such as the intake air temperature sensor 13 and IC 17 on the circuit board 12 correspond to the "electronic components" of the present invention.

[0051] As shown in Figures 8 and 15, multiple left-side mold contact pins 15g are provided protruding from the left side of the top surface 15d, and each left-side mold contact pin 15g is distributed on the top surface 15d. When the mold is closed during injection molding of the casing 11, the left end of each left-side mold contact pin 15g is pressed against the inner wall of the left side of the mold.

[0052] Four fitting pins 15h are provided protruding to the right from the perimeter of the left base portion 15a, and each fitting pin 15h is fitted into a fitting hole 16e of the right protective member 16. This keeps the left and right protective members 15 and 16 sandwiching the circuit board 12. These fitting pins 15h and fitting holes 16e correspond to the "first fitting portion" of the present invention. The pin bodies 15b are arranged in a vertical row in front of the left base portion 15a and extend horizontally. The right end of each pin body 15b functions as a positioning pin 15i, and the left end functions as a left mold contact pin 15j. When the mold is closed during injection molding of the casing 11, the left end of each left mold contact pin 15j is pressed against the inner wall of the left mold, causing each positioning pin 15i to contact the terminal insert portion 16b of the right protective member 16.

[0053] The sensor retainer portion 15c is positioned to correspond to the sensor body 14a of the intake pressure sensor 14 and contacts the sensor body 14a from the left. A left-side mold contact pin 15k is also provided protruding from the left side of the sensor retainer portion 15c and is pressed by the inner wall of the left mold during injection molding of the casing 11. This sensor retainer portion 15c and the pressure case portion 16d of the right protective member 16 described above correspond to the "sensor displacement restricting portion" of the present invention. Furthermore, the left-side mold contact pins 15g, 15j, and 15k of the left protective member 15 and the right-side mold contact pin 16f of the right protective member 16 described above correspond to the "mold contact portion" of the present invention.

[0054] In the positional relationship with the circuit board 12 as described above, the left and right protective members 15 and 16 are embedded in the casing 11 of the sensor unit 10. The sensor unit 10 is mounted on the vehicle with the throttle device 1 attached, and a harness from the ECU (engine control unit) mounted on the vehicle is connected to its connector 21. The throttle opening, intake air temperature, and intake pressure output from the sensor unit 10 are input to the ECU, and the engine operating state is controlled by the ECU based on this detection information. The throttle opening, intake air temperature, and intake pressure correspond to the "state of intake air" in this invention, and the ECU corresponds to the "device to which the signal from the sensor is output" in this invention.

[0055] Procedure for injection molding of casing 11 Next, the procedure for injection molding the casing 11 of the sensor unit 10 will be described. First, as shown in Figures 7 and 8, an excitation conductor 8b and a signal detection conductor 8c are formed on the circuit board 12 along with a wiring pattern 12a, and the IC 17, electronic components, intake air temperature sensor 13, and intake pressure sensor 14 are mounted. In addition, the left and right protective members 15 and 16 are manufactured, for example by injection molding, and five connector terminals 18 are embedded in the terminal insert portion 16b of the right protective member 16 as insert parts.

[0056] Next, the right protective member 16 is assembled to the circuit board 12 from the right. That is, while inserting the intake air temperature sensor 13 on the circuit board 12 into the recessed housing portion 16g of the detector 16c of the right protective member 16, the right base portion 16a of the right protective member 16 is superimposed on the right side of the circuit board 12. The pressure case portion 16d of the right protective member 16 abuts against the sensor body 14a of the intake pressure sensor 14, and each connector terminal 18 is arranged in a predetermined position on the circuit board 12, so the base end of each connector terminal 18 is soldered onto the circuit board 12.

[0057] Furthermore, when the left protective member 15 is placed on the circuit board 12 from the left, its four fitting pins 15h on its outer circumference fit into the fitting holes 16e of the right protective member 16. As a result, the circuit board 12 is sandwiched and integrated by the left and right protective members 15 and 16, the sensor retaining portion 15c contacts the sensor body 14a of the intake pressure sensor 14, and each positioning pin 15i contacts the terminal insert portion 16b of the right protective member 16.

[0058] Then, in this state, the circuit board 12 and the left and right protective members 15 and 16 are placed inside the injection molding die, and the die is closed. The inner wall of the right mold contacts the right side of the right protective member 16, more specifically the right side of the right base portion 16a, the right end of each right mold contact pin 16f, and the right side of the pressure case portion 16d, respectively, and presses to the left. At the same time, the inner wall of the left mold contacts the left side of the left protective member 15, more specifically the left end of each left mold contact pin 15g, 15j, and 15k, respectively, and presses to the right.

[0059] Consequently, the right base portion 16a of the right protective member 16, the circuit board 12, and the left base portion 15a of the left protective member 15 are sandwiched without any gaps between the left and right molds. As a result, the right base portion 16a abuts against the right side surface of the circuit board 12, and the open end of the concave housing portion 16g of the right base portion 16a abuts against the right side surface of the circuit board 12. As a result, the entire right side surface of the circuit board 12 and the intake air temperature sensor 13 inside the concave housing portion 16g are isolated from the outside, that is, isolated from the inside of the mold cavity in this state.

[0060] In conjunction with this, the open ends of each recessed housing portion 15f of the left base portion 15a each abut against the left side surface of the circuit board 12. As a result, each region on the left side surface of the circuit board 12 is individually housed within the recessed housing portion 15f, and electronic components such as IC 17 and soldering points 18a, 13c, and 14c within those regions are also housed within the recessed housing portion 15f. Consequently, the entire left side surface of the circuit board 12, as well as the electronic components and soldering points 18a, 13c, and 14c, are isolated from the cavity of the mold.

[0061] In this state, molten resin is injected into the mold cavity and spreads throughout, then cools and hardens to form the casing 11, thus completing the production of the sensor unit 10. As is clear from the above explanation, the production of the sensor unit 10 can be completed by injection molding the casing 11 with the circuit board 12 and the left and right protective members 15 and 16 as insert parts. Therefore, it is not necessary to perform mold molding after injection molding of the casing, as in the technology of Patent Document 1, and the manufacturing process can be simplified by the amount equivalent to mold filling, thereby reducing manufacturing costs.

[0062] On the other hand, if the high-temperature, high-pressure molten resin injected into the cavity in this manner comes into contact with the circuit board 12, it can cause warping; if it comes into contact with electronic components, it can cause damage; and if it comes into contact with solder joints 18a, 13c, and 14c, it can cause the solder to peel off. In this embodiment, these situations are prevented by the left and right protective members 15 and 16, and their effects will be explained below.

[0063] Effects of protective members 15 and 16 The right base portion 16a of the right protective member 16 abuts against the right side surface of the circuit board 12, isolating the right side from the mold cavity and preventing contact with the molten resin. Furthermore, since the open end of the recessed housing portion 16g of the right protective member 16 abuts against the right side surface of the circuit board 12, the intake air temperature sensor 13 within the recessed housing portion 16g is isolated from the mold cavity and prevented from contact with the molten resin. The right protective member 16, with its high heat resistance and rigidity, maintains its intended shape without deforming even when in contact with the molten resin. Therefore, the molten resin within the cavity cools and hardens without contacting the right side surface of the circuit board 12 or the intake air temperature sensor 13. Consequently, the right side surface of the circuit board 12 and the intake air temperature sensor 13 are prevented from directly receiving the heat and pressure of the molten resin. In addition, the air present within the recessed housing portion 15f functions as an insulating layer, preventing heat transfer from the molten resin to the intake air temperature sensor 13.

[0064] Furthermore, since the open ends of each recessed housing portion 15f of the left protective member 15 abut against the left side surface of the circuit board 12, the electronic components and soldering points 18a, 13c, and 14c are isolated from the mold cavity along with this left side surface, preventing contact with the molten resin. In addition, because the left protective member 15 maintains its intended shape due to its high heat resistance and rigidity, the left side surface of the circuit board 12 and the electronic components and soldering points 18a, 13c, and 14c are prevented from being directly exposed to the heat and pressure of the molten resin. The air inside the recessed housing portion 15f also functions as an insulating layer, similar to the case of the right protective member 16.

[0065] In this way, electronic components such as the intake air temperature sensor 13 and IC 17 on the circuit board 12, as well as soldering points 18a, 13c, and 14c, are prevented from coming into contact with the molten resin and are thus spared from direct effects of heat and pressure. Consequently, problems such as damage to electronic components and delamination of soldering points 18a, 13c, and 14c caused by these factors can be prevented.

[0066] Furthermore, since contact of molten resin with both sides of the circuit board 12 is prevented, warping of the circuit board 12 due to heat and pressure can be prevented. Specifically, the right base portion 16a abuts against the entire right side of the circuit board 12, and the open ends of each concave housing portion 15f of the left base portion 15a abut against the entire left side of the circuit board 12, so that the effects of heat and pressure from the molten resin on both sides of the circuit board 12 are mitigated. That is, not only are the heat and pressure acting on both sides reduced, but they are also nearly balanced, so the circuit board 12 remains flat without warping. Therefore, it is possible to prevent problems such as damage to electronic components and delamination of solder joints 18a, 13c, and 14c caused by warping of the circuit board 12 at any point on the circuit board 12.

[0067] In addition, the high rigidity of the left and right protective members 15 and 16 that sandwich the circuit board 12 also contributes to preventing warping. That is, by being sandwiched between these protective members 15 and 16, the positional displacement in the left-right direction is restricted at any point on the entire surface of the circuit board 12, and as a result, the occurrence of warping can be prevented even more reliably.

[0068] Furthermore, preventing warping of the circuit board 12 also contributes to preventing molten resin from entering the recessed housing portions 15f and 16g. That is, if warping occurs in the circuit board 12, gaps will be created between the circuit board and the open ends of each recessed housing portion 15f and 16g, allowing molten resin to enter the interior. By preventing warping, the circuit board 12 is kept in its original flat shape, which prevents molten resin from entering the recessed housing portions 15f and 16g. Therefore, problems such as damage to electronic components and delamination of solder joints 18a, 13c, and 14c can be prevented more reliably.

[0069] On the other hand, in this embodiment in particular, since the left side surface of the circuit board 12 is covered by multiple recessed housing portions 15f of the left protective member 15, the above-mentioned trouble prevention effect can be achieved more reliably. For example, even if only an annular partition wall 15e surrounding the left base portion 15a is formed to create a single recessed housing portion 15f, the left side surface of the circuit board 12 and the electronic components and soldering points 18a, 13c, 14c can be isolated from the outside. However, if a gap occurs between the circuit board 12 and any of the open ends of each recessed housing portion 15f, the heat and pressure of the molten resin that has entered the interior will cause warping across the entire surface of the circuit board 12, and the effects of heat and pressure will extend to all the electronic components and soldering points 18a, 13c, 14c.

[0070] By dividing the left side surface of the circuit board 12 into multiple recessed housing sections 15f, even if molten resin enters any of these sections, the affected area is small, thus reducing warping of the circuit board 12. Furthermore, even if molten resin enters a recessed housing section 15f that does not contain electronic components, no problems occur, and even in the case of a recessed housing section 15f that houses soldering points 18a, 13c, and 14c, delamination does not necessarily occur. Therefore, in such cases, the original function of the sensor unit 10 can be maintained, resulting in the added benefit of improved reliability. In addition, the grid-like partition walls 15e function as ribs that reinforce the left base section 15a, thereby improving the rigidity of the left protective member 15 and contributing to preventing warping of the circuit board 12.

[0071] However, the present invention is not limited thereto. For example, a single recessed housing portion 15f may be formed in the left protective member 15 as described above, and an area corresponding to substantially the entire circuit board 12 may be housed inside.

[0072] Furthermore, in this embodiment, the positional relationship between the left and right protective members 15 and 16 is precisely determined by the fitting of the fitting pin 15h and the fitting hole 16e, and the positional relationship between the right protective member 16 and the circuit board 12 is also precisely determined via the connector terminal 18. As a result, the recessed housing portion 16g of the right protective member 16 and the recessed housing portions 15f of the left protective member 15 each precisely contact the desired area on the circuit board 12, thereby more reliably preventing contact with the molten resin. In addition, since the circuit board 12 is sandwiched and integrated between the left and right protective members 15 and 16 before being placed in the mold, the injection molding process can be carried out more easily compared to, for example, when each member is placed individually in the mold.

[0073] Meanwhile, the terminal insert portion 16b of the right protective member 16 and the pin bodies 15b of the left protective member 15 are sandwiched without any gaps between the closed left and right molds. As a result, the terminal insert portion 16b is accurately positioned in the left-right direction, and each embedded connector terminal 18 is also positioned in the intended left-right position within the casing 11, thereby preventing poor contact of the connector 21. The terminal insert portion 16b of the right protective member 16 also contributes to the positioning of the connector terminals 18. When the right protective member 16 is injection molded, the right-angle bent portions of each connector terminal 18 are embedded as insert parts, so that each connector terminal 18 is kept at a predetermined interval in the vertical direction. As a result, each connector terminal 18 is positioned in the correct vertical position, thereby preventing poor contact of the connector 21.

[0074] Furthermore, when assembling the right protective member 16 to the circuit board 12, the terminal insert portion 16b acts as a jig for bundling each connector terminal 18, thus facilitating the assembly process. In addition, since the left and right protective members 15 and 16, which are originally intended to prevent contact with molten resin, are utilized, the above effects can be achieved without increasing the number of parts in the sensor unit 10.

[0075] Furthermore, the pressure case portion 16d of the right protective member 16, the sensor body 14a of the intake pressure sensor 14, and the sensor retaining portion 15c of the left protective member 15 are sandwiched without any gaps between the closed left and right molds. This ensures that the sensor body 14a is accurately positioned in the left-right direction, or in other words, in the thickness direction of the circuit board 12, thereby reliably preventing leakage of intake pressure. In addition, the opening of the sensor body 14a is closed by the pressure case portion 16d of the right protective member 16, preventing molten resin from flowing into the interior, thus preventing damage to the intake pressure sensor 14 due to the heat and pressure of the molten resin. This effect can also be achieved by using the left and right protective members 15 and 16 without increasing the number of parts.

[0076] On the other hand, the left protective member 15 is pressed against the inner wall of the left mold via the left mold contact pins 15g, 15j, and 15k, and molten resin is interposed between the inner wall of the mold and the left base portion 15a and sensor retaining portion 15c to form the casing 11. As a result, as shown in Figure 1, only the end faces of the left mold contact pins 15g, 15j, and 15k are exposed to the outside on the left side of the casing 11 after injection molding. If the left mold contact pins 15g, 15j, and 15k were not formed, the entire left side of the left protective member 15 would be exposed to the outside, which would be unsightly. However, this method prevents such problems and improves the aesthetic appearance of the sensor unit 10.

[0077] Furthermore, at this time, the left protective member 15 is not only pressed against the left mold via the left mold contact pins 15g, 15j, and 15k, but is also subjected to the pressure of the molten resin interposed between it and the inner wall of the mold. As a result, the open ends of each concave housing portion 15f come into stronger contact with the circuit board 12, providing the effect of more reliably preventing the intrusion of molten resin into the interior.

[0078] This concludes the description of the embodiments. However, the present invention is not limited to these embodiments and can be modified in various ways, which will be described below as Alternative Examples 1 to 6. In each Alternative Example, the same component numbers are used for parts with the same configuration as in the embodiments, and their descriptions are omitted. The differences will be described in detail.

[0079] 《Another example 1》 In the above embodiment, the positional relationship between the left and right protective members 15 and 16 is determined by the fitting of the mating pin 15h and the mating hole 16e, while the positional relationship between the right protective member 16 and the circuit board 12 is naturally determined via the existing connector terminal 18. However, the embodiment is not limited to this.

[0080] Figure 18 is an exploded perspective view corresponding to Figure 8, showing a sensor unit 10 of another example 1 in which the right protective member 16 and the circuit board 12 are positioned via a fitting pin and a fitting hole.

[0081] As shown in this figure, a pair of fitting pins 31 may be provided protruding from the left side of the right base portion 16a and fitted into a pair of fitting holes 32 that penetrate the circuit board 12. These fitting pins 31 and fitting holes 32 correspond to the "second fitting portion" of the present invention. In this case, the right protective member 16 and the circuit board 12 can be positioned more accurately.

[0082] 《Another example 2》 In the above embodiment, the entire left side surface of the circuit board 12 is covered by each of the recessed housing portions 15f of the left protective member 15. However, it is not necessarily required to provide recessed housing portions 15f in areas where contact with molten resin does not pose a problem.

[0083] Figure 19 is a perspective view corresponding to Figure 6, showing another example of the sensor unit 10 in which the soldering point 18a of the connector terminal 18 is exposed to the outside.

[0084] If high-melting-point solder is used to solder the connector terminals 18, there is no risk of delamination or other damage occurring even if it comes into contact with molten resin. Therefore, as shown in this figure, the area of ​​the left protective member 15 corresponding to the soldering location 18a may be exposed to the outside through the opening 41 without forming a recessed housing portion 15f. Even after the circuit board 12 is sandwiched between the left and right protective members 15 and 16, the connector terminals 18 can be soldered through the opening 41, making the work easier to perform.

[0085] 《Another example 3》 In the above embodiment, the right base portion 16a of the right protective member 16 covers the entire right side surface of the circuit board 12. However, it is not necessary to cover any area that does not cause warping of the circuit board 12.

[0086] Figure 20 is a perspective view showing the right protective member 16 of the sensor unit 10 of alternative example 3, in which notches are formed at three locations on the outer circumference of the right base portion 16a, and Figure 21 is a front view showing the sensor unit 10 of alternative example 3 after the casing 11 has been molded.

[0087] As shown in these figures, three rectangular notches 51 are formed on the outer circumference of the right base portion 16a, and the right side of the circuit board 12 is exposed to the outside in the area of ​​each notch 51. When the casing 11 is injection molded, the molten resin flows into each notch 51, and after cooling and hardening, the circuit board 12, the right protective member 16, and the casing 11 are integrated at each notch 51. Therefore, the strength of the sensor unit 10 can be improved by more firmly bonding each member 12, 16, and 11.

[0088] 《Another example 4》 In the above embodiment, electronic components and the like were housed in a hollow space within each concave housing portion 15f, but the embodiment is not limited to this.

[0089] Figure 22 is a partial cross-sectional view showing another example 4 of the sensor unit 10, in which an elastic cushioning material is filled into the recessed housing portion of the left protective member.

[0090] In this example, a cushioning material 61 is filled into the recessed housing portion 15f that houses the IC 17. Any elastic synthetic resin material can be arbitrarily selected as the cushioning material 61, such as epoxy, urethane, or polyamide. When the left protective member 15 is placed on the circuit board 12, the cushioning material elastically deforms within the recessed housing portion 15f to enclose the IC 17, and in this state, the open end of the recessed housing portion 15f abuts against the circuit board 12, isolating it from the outside.

[0091] While the sensor unit 10 is mounted on the vehicle, the temperature inside the recessed housing 15f changes due to heat received from the nearby engine, etc., but the pressure changes associated with this are mitigated by the buffer material 61. Therefore, compared to the case where the buffer material 61 is not present, IC17 is kept in an environment with less pressure change, and the stress generated in response to the pressure change can be reduced, thereby suppressing damage and deterioration of IC17 caused by pressure changes. Note that the buffer material 61 may also be filled inside other recessed housings 15f. 《Another example 5》 In the above embodiment, the positional relationship between the left and right protective members 15 and 16 is determined by the fitting of the fitting pin 15h and the fitting hole 16e, but this is not limited to any structure that allows for positioning.

[0092] Figure 23 is a perspective view corresponding to Figure 6, showing a sensor unit 10 of another example 5 in which the circuit board is sealed by fitting protrusions and grooves formed around the left and right protective members 15 and 16. Figure 24 is a cross-sectional perspective view corresponding to Figure 14, also showing a sensor unit 10 of another example 5.

[0093] As shown in these figures, a continuous ridge 71 is integrally formed around the left protective member 15, extending around its entire circumference, and a continuous groove 72 is integrally formed around the right protective member 16, extending around its entire circumference. These ridges 71 and grooves 72 correspond to the "third fitting portion" of the present invention.

[0094] When the circuit board 12 is sandwiched between the left and right protective members 15 and 16, the protrusion 71 fits into the groove 72, thereby sealing the circuit board 12 between the left and right protective members 15 and 16 and isolating it from the outside. Consequently, the intrusion of molten resin is prevented even at the fitting point between the protrusion 71 and the groove 72, and as a result, the prevention of warping of the circuit board 12 and the protection of electronic components and soldering points 18a, 13c, and 14c can be achieved more reliably.

[0095] 《Another example 6》 In the above embodiment, the connector terminals 18 of the circuit board 12 are arranged inside the connector cylindrical portion 21a provided in the casing 11 to form the connector 21, but the invention is not limited to this.

[0096] Figure 25 is an exploded perspective view corresponding to Figure 8, showing the sensor unit 10 of another example 6 with a card edge connector, and Figure 26 is a cross-sectional view corresponding to Figure 16, also showing the sensor unit 10 of another example 6.

[0097] As shown in these figures, the circuit board 12 extends further forward compared to the embodiment and protrudes into the connector cylindrical portion 21a of the casing 11. Five contacts 81a of the card edge connector 81 are arranged in a vertical row on the front edge of the circuit board 12, each connected to a wiring pattern on the circuit board 12. The connector 21 is formed by this card edge connector 81 and the connector cylindrical portion 21a. Even with this configuration, the same effects and advantages as in the above embodiment can be achieved.

[0098] The embodiments of the present invention are not limited to the above embodiments and alternative examples 1 to 6. For example, in the above embodiments and each alternative example, the invention is embodied in a sensor unit 10 of a throttle device 1 equipped with a single throttle bore 2a mounted on a motorized bicycle, but the target vehicle and the type of throttle device 1 are not limited thereto, and for example, a four-wheeled vehicle may be targeted. Alternatively, it may be targeted in small two-wheeled vehicles such as scooters and mopeds, larger motorcycles, or saddle-type vehicles such as ATVs (All Terrain Vehicles) such as four-wheeled buggies. Furthermore, the sensor unit of the present invention may be applied to the throttle device of an engine used for purposes other than a driving power source, for example, a generator engine. Moreover, it may be embodied as a sensor unit for a multi-throttle device equipped with multiple throttle bores.

[0099] Furthermore, in the above embodiments and each of the alternative examples, the sensor unit 10 is embodied as having a throttle opening sensor 8, an intake air temperature sensor 13, and an intake pressure sensor 14. However, it is not necessarily required to have all sensors 8, 13, and 14, and any of the sensors may be omitted, for example, depending on the requirements from engine control.

[0100] Furthermore, although the protective members 15 and 16 are made of synthetic resin in the above embodiment, the material is not limited to this. For example, if measures are taken to prevent short circuits in the wiring patterns and electronic components on the circuit board 12, the protective members 15 and 16 may be made of a metal material such as aluminum.

[0101] Furthermore, in the above embodiment, the right base portion 16a of the right protective member 16 is made into a flat plate and superimposed on the right side surface of the circuit board 12, but this is not the only option. For example, if electronic components or soldering points are provided on the right side surface of the circuit board 12, a recessed housing portion may also be formed in the right base portion 16a to isolate the electronic components, etc., from the outside.

[0102] Furthermore, in the above embodiment, the left and right protective members 15 and 16 were formed as inserts together with the circuit board 12, and the casing 11 was molded to the desired shape in a single injection molding process. However, the invention is not limited to this. For example, the casing 11 may be divided into left and right halves with the circuit board 12 as the boundary. The right half of the casing in Figure 4 may be formed by a preceding injection molding process, and the left half of the casing may be integrally formed with this right half by a subsequent injection molding process to achieve the desired shape of the casing 11.

[0103] In the preceding injection molding, a portion corresponding to the right base portion 16a of the right protective member 16 and a portion corresponding to the detector 16c, which has a recessed housing portion 16g in which the intake air temperature sensor 13 is housed, are integrally formed on the left side surface of the right casing. In addition, portions corresponding to the pressure case portion 16d and terminal insert portion 16b of the intake pressure sensor 14 may also be integrally formed. In the subsequent injection molding, the circuit board 12 and the left protective member 15 are placed in the mold as insert parts. The right casing corresponds to the "first casing" of the present invention, and the left casing corresponds to the "second casing" of the present invention.

[0104] Then, when the mold is closed, each of the recessed housing portions 15f of the left protective member 15 abuts against the left side surface of the circuit board 12, and the portion corresponding to the right base portion 16a of the right casing abuts against the right side surface of the circuit board 12, sandwiching the circuit board 12. In this state, molten resin is injected into the cavity to form the casing 11. Even with the above configuration, the effects and advantages described in the above embodiment can be achieved.

[0105] Comparing this alternative example with the above embodiment, the number of parts can be reduced because the production of the right protective member 16 is unnecessary in this alternative example. On the other hand, if the portion corresponding to the right base portion 16a of the right casing deforms due to the heat and pressure of the molten resin during subsequent injection molding, a gap will be created when it comes into contact with the right side surface of the circuit board 12. For this reason, in the injection molding of the right casing, it is desirable to take measures such as using a synthetic resin material that has high heat resistance and rigidity, similar to the protective members 15 and 16.

[0106] Furthermore, in the above embodiment, when the right protective member 16 is injection molded, the right-angled bent portions of each connector terminal 18 are embedded as inserts, but this configuration is not necessarily required. For example, instead of embedding the connector terminals 18 in the right protective member 16, their base ends may be soldered to the circuit board 12, and then the connector terminals 18 may be embedded together with the circuit board 12 during the injection molding of the casing 11.

[0107] In addition, five positioning pins may be integrally molded into the right protective member 16 so as to be opposite to the five positioning pins 15i of the left protective member 15, and when the mold is closed, the left and right positioning pins 15i will sandwich each connector terminal 18 from the left and right. This allows each connector terminal 18 to be positioned in the left-right direction, in other words, in the thickness direction of the circuit board 12. The positioning pins 15i of the left protective member 15 and the positioning pins of the right protective member 16 correspond to the "terminal displacement restricting part" of the present invention. [Explanation of symbols]

[0108] 1. Throttle device 2a Throttle bore 8. Throttle position sensor 10 Sensor Units 11 Casing 12 Circuit boards 13. Intake air temperature sensor (electronic component) 13c, 14c, 18a soldering points 14. Intake pressure sensor 15. Left protective component (second protective component) 15c Sensor retaining part (sensor displacement restricting part) 15f Recessed storage section 15g, 15j, 15k Left side mold contact pin (mold contact part) 15h Mating pin (first mating part) 15i Positioning pin (terminal displacement restricting part) 16 Right protective member (first protective member) 16d Pressure case section (sensor displacement restricting section) 16e Fitting hole (first fitting part) 16f Right side mold contact pin (mold contact part) 17 IC (electronic components) 18 Connector terminals 21 Connectors 31. Mating pin (second mating part) 32 Fitting hole (second fitting part) 41 Opening 51 Notches 61 Cushioning material 71. Protrusion (third fitting part) 72. Recessed groove (third fitting part)

Claims

1. In a throttle device sensor unit attached to a throttle device that adjusts the intake air of an engine, A circuit board connected to a sensor that detects the state of intake air flowing through the throttle bore of the throttle device, and which outputs a signal from the sensor to the outside, A casing manufactured by injection molding synthetic resin material with the aforementioned circuit board as an insert, The first and second protective members are embedded as inserts during injection molding of the casing together with the circuit board, and are arranged on both sides of the circuit board, each in contact with the circuit board. The first and second protective members are integrally formed with at least one of them, and have a shape that opens towards the circuit board, with the opening end abutting against the circuit board to house a predetermined area on the circuit board and isolate it from the outside, comprising: At least one of the first and second protective members has an opening that exposes the soldering points on the circuit board to the outside. A sensor unit for a throttle device characterized by the following features.

2. A sensor unit for a throttle device that is attached to a throttle device that adjusts the intake air of an engine, A circuit board connected to a sensor that detects the state of intake air flowing through the throttle bore of the throttle device, and which outputs a signal from the sensor to the outside, A casing manufactured by injection molding synthetic resin material with the aforementioned circuit board as an insert, The first and second protective members are embedded as inserts during injection molding of the casing together with the circuit board, and are arranged on both sides of the circuit board, each in contact with the circuit board. The first and second protective members are integrally formed with at least one of them, and have a shape that opens towards the circuit board, with the opening end abutting against the circuit board to house a predetermined area on the circuit board and isolate it from the outside, comprising: At least one of the first and second protective members has a notch that exposes the circuit board to the outside, and molten resin from the injection molding of the casing flows into the notch and becomes integrated with it. A sensor unit for a throttle device characterized by the following features.

3. A sensor unit for a throttle device that is attached to a throttle device that adjusts the intake air of an engine, A circuit board connected to a sensor that detects the state of intake air flowing through the throttle bore of the throttle device, and which outputs a signal from the sensor to the outside, A casing manufactured by injection molding synthetic resin material with the aforementioned circuit board as an insert, The first and second protective members are embedded as inserts during injection molding of the casing together with the circuit board, and are arranged on both sides of the circuit board, each in contact with the circuit board. The first and second protective members are integrally formed with at least one of them, and have a shape that opens towards the circuit board, with the opening end abutting against the circuit board to house a predetermined area on the circuit board and isolate it from the outside, comprising: The circuit board has connector terminals that constitute a connector connected to a device to which the signal from the sensor is output. The first and second protective members each have a terminal displacement restricting portion integrally formed therein. The terminal displacement restricting section clamps the connector terminal from both sides and positions it in the thickness direction of the circuit board. A sensor unit for a throttle device characterized by the following features.

4. A sensor unit for a throttle device that is attached to a throttle device that adjusts the intake air of an engine, A circuit board connected to a sensor that detects the state of intake air flowing through the throttle bore of the throttle device, and which outputs a signal from the sensor to the outside, A casing manufactured by injection molding synthetic resin material with the aforementioned circuit board as an insert, The first and second protective members are embedded as inserts during injection molding of the casing together with the circuit board, and are arranged on both sides of the circuit board, each in contact with the circuit board. The first and second protective members are integrally formed with at least one of them, and have a shape that opens towards the circuit board, with the opening end abutting against the circuit board to house a predetermined area on the circuit board and isolate it from the outside, comprising: At least one of the first and second protective members has a sensor displacement restricting portion integrally formed therein. The sensor displacement restricting unit is positioned in the thickness direction of the circuit board by contacting the sensor. A sensor unit for a throttle device characterized by the following features.

5. The recessed housing portion accommodates an area within which the predetermined region corresponds to substantially the entire area of ​​the circuit board. A sensor unit for a throttle device according to any one of claims 1 to 4.

6. The recessed housing portion houses, as the predetermined region, an area including electronic components mounted on the circuit board. A sensor unit for a throttle device according to any one of claims 1 to 4.

7. The recessed housing portion houses the area on the circuit board, including the soldering points, as the predetermined region. A sensor unit for a throttle device according to any one of claims 1 to 4.

8. The aforementioned recessed housing portions are provided corresponding to a plurality of regions on the circuit board, and each of the plurality of regions is individually housed inside. A sensor unit for a throttle device according to any one of claims 1 to 4.

9. The aforementioned concave housing is filled with an elastic cushioning material. A sensor unit for a throttle device according to any one of claims 1 to 4.

10. The circuit board has connector terminals that constitute a connector connected to a device to which the signal from the sensor is output. The first or second protective member is manufactured by injection molding a synthetic resin material. The connector terminal is partially embedded as an insert during injection molding of the first or second protective member, and its base end is soldered to the circuit board. A sensor unit for a throttle device according to any one of claims 1 to 4.

11. The first and second protective members are made of a synthetic resin material that has higher heat resistance and rigidity compared to the material of the circuit board. A sensor unit for a throttle device according to any one of claims 1 to 4.

Images