Circuit device

Abstract

The present invention addresses the problem of providing a circuit device in which thermal stress acting on the interface between a conductor sheet and a sealing material can be reduced, and peeling of the sealing material from a housing can be suppressed. A physical quantity measurement device (20) constituting a circuit device is provided with: a housing (201) in which an opening for a circuit chamber (235) is provided on the front surface (221); three or more conductor pieces (301) which are insert-molded in the case (201) and have tips (312a) exposed in parallel in the circuit chamber; a circuit board (207) housed in the circuit chamber; a wire (303) that connects the three or more conductor pieces and the circuit board; and a sealing material (211) filled in the circuit chamber, in which the cross-sectional area of tip sections (312a, 313a) located in the middle of the three or more conductor sheets is smaller than the cross-sectional area of tip sections (311a, 314a) located at both ends in the arrangement direction.

Description

Technical Field

[0001] The present invention relates to a circuit device such as a physical quantity detection device for detecting a physical quantity of intake air sucked into an internal combustion engine of a vehicle. Background Art

[0002] Patent Document 1 discloses a configuration of an air flow measurement device in which a sensor assembly and a connector terminal are connected by bonding wires and insert-molded in a resin case. Prior art literature Patent Literature

[0003] Patent Document 1: Japanese Patent Application Laid-Open No. 2014-219297 Summary of the invention Problem that the invention aims to solve

[0004] The air flow meter of Patent Document 1 is a device installed in the intake passage of the engine used for driving a vehicle. Since it is placed in the high temperature environment of the engine room, there is a possibility that thermal stress acts on the connector terminal. For example, if thermal stress is generated at the interface between the connector terminal made of metal and the sealing material made of epoxy resin and acts on the sealing material, the sealing material may be peeled off from the housing, and stress may be applied to the welding wire, causing the wire to break.

[0005] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a circuit device capable of reducing thermal stress generated at the interface between a terminal and a sealing material and suppressing separation of the sealing material from a housing. Technical means of solving problems

[0006] The circuit device of the present invention for solving the above-mentioned problem comprises: a housing having an opening of a circuit chamber on the front; three or more conductor sheets, which are insert-molded in the housing and whose top ends are exposed in parallel in the circuit chamber; a circuit substrate, which is accommodated in the circuit chamber; a wire connecting the three or more conductor sheets and the circuit substrate; and a sealing material filled in the circuit chamber, wherein the cross-sectional area of ​​the top end of at least one of the three or more conductor sheets located in the middle is smaller than the cross-sectional area of ​​the top ends located at both ends of the arrangement direction. Effects of the Invention

[0007] According to the present invention, the thermal stress acting on the interface between the conductor sheet of the sealing material and the sealing material can be reduced, and the sealing material can be prevented from peeling off from the housing. Further features related to the present invention will become clear from the description of this specification and the accompanying drawings. In addition, the above-mentioned topics, structures and effects will be clarified through the description of the following embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 1 is a system diagram of an internal combustion engine control system 1 of an electronic fuel injection system to which the circuit device of the present invention is applied. Figure 2 It is a front view of the physical quantity measuring device. Figure 3 It is a diagram for explaining the internal structure of the physical quantity measuring device. Figure 4 This is a diagram showing a state where a connector terminal and a terminal block of a circuit board are connected by wires. Figure 5 This is a diagram showing a part of the physical quantity measuring device in a cross section along a connector terminal. Figure 6 It is a figure which shows the cross section of a connector terminal. Figure 7 It is a diagram for explaining the relationship between the shape of the side wall surface of the circuit chamber and the shape of the connector terminal. Figure 8 It is a diagram for explaining the shape of the contraction portion. Fig. 9 This is a diagram showing the injection direction of the molding resin in injection molding. DETAILED DESCRIPTION

[0009] Hereinafter, embodiments of a circuit device according to the present invention will be described with reference to the drawings.

[0010] Figure 1 This is an overall diagram showing the configuration of a vehicle internal combustion engine system to which the circuit device of the present invention is applied. In this embodiment, the circuit device of the present invention is described as a physical quantity measuring device that measures the physical quantity of intake air in an internal combustion engine control system 1 .

[0011] In the internal combustion engine control system 1, based on the operation of the internal combustion engine 10 having the engine cylinder 11 and the engine piston 12, intake air is sucked from the air cleaner 21 as the measured gas 2. The intake air is introduced into the combustion chamber of the engine cylinder 11 via the intake body as the main passage 22, the throttle body 23, and the intake manifold 24. The physical quantity of the measured gas 2 as the intake air introduced into the combustion chamber is measured by the physical quantity measuring device 20. Then, based on the physical quantity measured by the physical quantity measuring device 20, fuel is supplied from the fuel injection valve 14 and introduced into the combustion chamber in the state of a mixed gas together with the intake air.

[0012] The fuel injection valve 14 is provided at the intake port of the internal combustion engine 10. The fuel injected into the intake port is mixed with the intake air. The mixture of the fuel and the intake air is introduced into the combustion chamber via the intake valve 15 and burns to generate mechanical energy. The mixture introduced into the combustion chamber is in a state of a mixture of fuel and air, and is explosively burned by spark ignition of the spark plug 13 to generate mechanical energy. The combusted gas is introduced into the exhaust pipe from the exhaust valve 16 and discharged from the exhaust pipe to the outside of the vehicle as the exhaust gas 3.

[0013] The flow rate of the measured gas 2 as the intake air introduced into the combustion chamber is controlled by the throttle valve 25, and the opening degree of the throttle valve 25 changes based on the operation of the accelerator pedal. In addition, the fuel supply amount is controlled according to the flow rate of the intake air introduced into the combustion chamber. By controlling the opening degree of the throttle valve 25 to control the flow rate of the intake air introduced into the combustion chamber, the mechanical energy generated by the internal combustion engine 10 can be controlled.

[0014] The physical quantity measuring device 20 measures physical quantities such as flow rate, temperature, humidity, and pressure of the measured gas 2, which is the intake air taken in through the air filter 21 and flows in the main passage 22. The physical quantity measuring device 20 outputs an electrical signal corresponding to the physical quantity of the intake air. The output signal of the physical quantity measuring device 20 is input to the control device 4.

[0015] In addition, the output of the throttle angle sensor 26 for measuring the opening of the throttle valve 25 is input to the control device 4. Furthermore, in order to measure the position and state of the engine piston 12, the intake valve 15, and the exhaust valve 16 of the internal combustion engine 10, and even the rotation speed of the internal combustion engine 10, the output of the rotation angle sensor 17 is input to the control device 4. In order to measure the state of the mixture ratio of the fuel amount and the air amount according to the state of the exhaust gas 3, the output of the oxygen sensor 28 is input to the control device 4.

[0016] The control device 4 calculates the fuel injection amount and the ignition timing based on the physical quantity of the intake air as the output of the physical quantity measuring device 20 and the rotation speed of the internal combustion engine 10 measured based on the output of the rotation angle sensor 17. Based on these calculation results, the fuel amount supplied from the fuel injection valve 14 and the ignition timing ignited by the spark plug 13 are controlled. In fact, the fuel supply amount and the ignition timing are further finely controlled based on the temperature measured by the physical quantity measuring device 20, the change state of the throttle angle, the change state of the engine speed, and the state of the air-fuel ratio measured by the oxygen sensor 28. Furthermore, in the idle operation state of the internal combustion engine 10, the control device 4 controls the air amount bypassing the throttle valve 25 through the idle air control valve 27 to control the rotation speed of the internal combustion engine 10 in the idle operation state.

[0017] The fuel supply amount and ignition timing, which are the main control quantities of the internal combustion engine 10, are calculated using the output of the physical quantity measuring device 20 as the main parameters. Therefore, the improvement of the measurement accuracy, the suppression of time-dependent changes, and the improvement of the reliability of the physical quantity measuring device 20 are important for improving the control accuracy of the vehicle and ensuring the reliability. In recent years, in particular, the requirements for saving fuel consumption of vehicles are very high, and the requirements for exhaust gas purification are very high. In order to meet these requirements, it is extremely important to improve the measurement accuracy of the physical quantity of the measured gas 2, i.e., the intake air, measured by the physical quantity measuring device 20. In addition, it is also important for the physical quantity measuring device 20 to maintain high reliability.

[0018] The vehicle equipped with the physical quantity measuring device 20 is used in an environment where the temperature and humidity change greatly. The physical quantity measuring device 20 preferably also considers the changes in temperature and humidity in the environment in which it is used, and the responses to dust, pollutants, etc. In addition, the physical quantity measuring device 20 is installed on the intake pipe that is affected by the heat from the internal combustion engine 10. Therefore, the heat generated by the internal combustion engine 10 is transferred to the physical quantity measuring device 20 via the intake pipe as the main passage 22. The physical quantity measuring device 20 measures the flow rate of the measured gas by heat transfer with the measured gas, so it is important to suppress the influence of heat from the outside as much as possible.

[0019] As described below, the physical quantity measuring device 20 mounted on the vehicle not only solves the problems recorded in the problem column to be solved by the invention, but also exerts the effects recorded in the effect column of the invention. As described below, the physical quantity measuring device 20 fully considers the above-mentioned various problems, solves various problems required as a product, and exerts various effects. The specific problems solved by the physical quantity measuring device 20 and the specific effects exerted are described in the description related to the following embodiments.

[0020] Figure 2 yes Figure 1 A front view of a physical quantity measuring device used in an internal combustion engine control system is shown. Figure 3 The seal is omitted Figure 2 The illustrated physical quantity measuring device is a front view of a sealing material in a circuit chamber, and a secondary passage is indicated by an imaginary line. Figure 4 This is a diagram showing a state where a connector terminal and a terminal block of a circuit board are connected by wires.

[0021] The physical quantity measuring device 20 is inserted into the main channel 22 from a mounting hole provided on the channel wall of the main channel 22 for use. The physical quantity measuring device 20 includes a housing 201 as an outer shell. The housing 201 is formed by injection molding a synthetic resin material composed of an insulating polymer resin such as polybutylene terephthalate (PBT) and polypropylene (PP), and a metal connector terminal 301 is insert molded.

[0022] The shell 201 has a flange 201f, a connector 201c and a measuring part 201m. The flange 201f is fixed on the air intake body serving as the main channel 22. The connector 201c protrudes from the flange 201f and is exposed to the outside from the air intake body for electrical connection with external equipment. The measuring part 201m extends in a manner of protruding from the flange 201f toward the center of the main channel 22.

[0023] The flange 201f has a generally rectangular shape in plan view and has a predetermined plate thickness, and has a through hole at a corner. The flange 201f is fixed to the main channel 22 by inserting a fixing screw through the through hole at the corner and screwing the fixing screw into the threaded hole of the main channel 22 .

[0024] The connector 201c has a connector terminal 301 whose one end is electrically connected to the circuit board and whose other end is electrically connected to the outside. The connector terminal 301 is composed of a plurality of plate-shaped conductors and is insert-molded in the housing 201.

[0025] The connector terminal 301 includes an output terminal, a power supply terminal, and a calibration terminal. The output terminal is used to output physical quantities such as flow rate and temperature as the measurement results of the physical quantity measuring device 20. The power supply terminal is used to supply direct current for the physical quantity measuring device 20 to operate. The calibration terminal measures the produced physical quantity measuring device 20, obtains the calibration value related to each physical quantity measuring device 20, and is used to store the calibration value in the memory inside the physical quantity measuring device 20.

[0026] The measuring part 201m is formed into a thin and long shape extending from the flange 201f toward the center direction of the main channel 22, and has a wide front face 221 and a rear face and a pair of narrow side wall faces 223 and 224. The measuring part 201m is inserted into the main channel 22 from a mounting hole provided in the main channel 22, for example, and is fixed to the main channel 22 via the flange 201f by bringing the flange 201f into contact with the main channel 22 and fixing it to the main channel 22 with screws. The measuring part 201m is arranged in the main channel 22 in such a manner that the side wall face 223 faces the upstream side of the flow direction of the measured gas in the main channel 22, and the side wall face 224 faces the downstream side of the flow direction of the measured gas.

[0027] The measuring section 201m is provided with a sub-channel 234 and a circuit chamber 235. The circuit chamber 235 is arranged at an upstream side of the flow direction of the measured gas 2 in the main channel 22, and the sub-channel 234 is arranged at a downstream side of the flow direction of the measured gas 2 in the main channel 22 than the circuit chamber 235.

[0028] The circuit substrate 207 is stored in the circuit chamber 235. The circuit chamber 235 is open at the front face 221 of the measuring section 201m, and a part of the circuit substrate 207 and the top ends 311 to 314 of the connector terminals 301 are exposed toward the front face of the housing. The circuit substrate 207 is made of, for example, a glass epoxy substrate, but may also be a substrate made of other materials. In addition, it may not be limited to a substrate but may be a metal conductive portion such as a terminal terminal or a lead frame. The circuit substrate 207 has a substantially rectangular shape extending along the length direction of the measuring section 201m, and circuit components 304 such as ICs and LSIs, chip components 305 such as chip capacitors and chip resistors, and terminal blocks 302 are mounted on its surface.

[0029] The terminal block 302 is disposed in the circuit chamber 235 at a position adjacent to the connector terminal 301 and is exposed toward the front of the housing in the circuit chamber 235. The terminal block 302 is connected to the top ends 311 to 314 of the connector terminal 301 by wire welding and terminal welding. Figure 4 As shown, the terminal block 302 has pads 321 to 324 made of aluminum.

[0030] like Figure 4 As shown, the circuit substrate 207 is wire bonded (bonded) to be electrically connected to the connector terminals 311 to 314. The wire bonding is performed by ultrasonically bonding the pads 321 to 324 and the connector terminals 311 to 314 using a wire material 303 such as aluminum bonding wires 331 to 334. After the wire bonding, Figure 2 As shown, the circuit chamber 235 is sealed by filling the sealing material 211. The sealing material 211 is a thermosetting adhesive that is liquid when injected and solidifies by heating. In this embodiment, an epoxy adhesive is used. The epoxy adhesive uses a two-component adhesive, but it can also be a one-component adhesive.

[0031] like Figure 3 As shown, one end of the auxiliary channel 234 opens at the side wall surface 223 of the measuring part 201m, branches in the middle, one end directly extends in a straight line and opens at the side wall surface 224 on the opposite side of the measuring part 201m, and the other end has the following shape: extends in a straight line toward the flange 201f of the measuring part 201m, bends toward the side wall surface 224 side and makes a U-turn toward the top of the measuring part 201m, and opens at the side wall surface 224 of the measuring part 201m in the middle. A thermal flow sensor 208 for measuring flow rate is arranged on the branch channel of the auxiliary channel 234.

[0032] The physical quantity measuring device 20 may be equipped with a thermometer, a hygrometer, and a pressure gauge (not shown) in addition to the thermal flow sensor 208 as an element for measuring the physical quantity of the intake air, and connected to the connector terminal 301 by wire bonding.

[0033] Next, the characteristic configuration of this embodiment will be described in detail. Figure 5 is a diagram showing a portion of a physical quantity measuring device in a cross section along a connector terminal. Figure 6 is a diagram showing a cross section of a connector terminal, Figure 7 It is a diagram for explaining the relationship between the shape of the side wall surface of the circuit chamber and the shape of the connector terminal.

[0034] The connector terminal 301 is composed of three or more conductor sheets. In the present embodiment, there are four connector terminals 311, 312, 313, and 314. These connector terminals 311 to 314 are insert-molded on the housing 201 in a manner that they are arranged in parallel with a predetermined interval. The connector terminals 311 to 314 are formed by punching out a metal plate so that the top ends are connected to each other (see Fig. 9 ) are separated from each other after the insert is molded into the housing 201.

[0035] Each connector terminal 311-314 has a base end portion 311b-314b protruding and exposed in the connector 201c and a tip end portion 311a-314a protruding and exposed in the circuit chamber 235. The base end portions 311b-314b are connected to the wiring harness in the connector 201c. The tip end portions 311a-314a are electrically connected to the circuit board 207 mounted inside the housing.

[0036] like Figure 5 As shown, the top end portions 311a~314a and the base end portions 311b~314b extend linearly along the extension direction of the measuring portion 201m at positions offset in the lateral width direction along the side wall surface 223 and the side wall surface 224 connecting the measuring portion 201m, and are connected to each other through continuous portions 311c~314c that are bent obliquely relative to the top end portions 311a~314a and the base end portions 311b~314b.

[0037] like Figure 5 and Figure 6 As shown, each connector terminal 311 to 314 is such that the connector terminals 312 and 313 disposed between these connector terminals 311 and 314 have smaller cross-sectional areas at the top end portions 312a and 313a than the connector terminals 311 and 314 on both sides. That is, when comparing the top end portions 311a and 314a of the connector terminals 311 and 314 on both sides (connector terminals on both sides) with the top end portions 312a and 313a of the connector terminals 312 and 313 disposed between them (middle connector terminals), the top end portions 312a and 313a of the connector terminals 312 and 313 have smaller cross-sectional areas.

[0038] In the present embodiment, since the connector terminals 311 to 314 are formed by blanking a single metal plate, they have the same thickness t. As shown in (2) of Figure 6 , the lateral widths w2 and w3 of the top ends 312a and 313a of the connector terminals 312 and 313 are narrower than the lateral widths w1 and w4 of the top ends 311a and 314a of the connector terminals 311 and 314.

[0039] As shown in Figure 6 , shrinkage portions 312d and 313d are provided on the top ends 312a and 313a of the connector terminals 312 and 313. The lateral widths w2 and w3 of the top ends of the shrinkage portions 312d and 313d are narrower than those of the base end sides of the shrinkage portions 312d and 313d, reducing the cross-sectional area. The shrinkage portions 312d and 313d are provided at positions buried in the measurement portion 201m by a predetermined length from the portion exposed in the circuit chamber 235 toward the base end sides of the connector terminals 312 and 313, which are closer to the connector terminals 312 and 313 than the side wall surfaces 235a to 235c of the circuit chamber 235.

[0040] The cross-sectional areas of the portions of the top ends 312a and 313a of the connector terminals 312 and 313, which are on the base end sides of the connector terminals 312 and 313 compared with the shrinkage portions 312d and 313d, are the same as the cross-sectional areas of the top ends 311a and 314a at both ends in the arrangement direction. That is, as shown in (3) of Figure 6 , the lateral widths of the portions of the top ends 312a and 313a of the connector terminals 312 and 313, which are on the base end sides of the shrinkage portions 312d and 313d, are the same as the lateral widths of the top ends 311a and 314a of the connector terminals 311 and 314 (w1 = w2 = w3 = w4), and the cross-sectional areas are also the same. And, as shown in (2) of Figure 6 , the lateral widths on the top end sides of the shrinkage portions 312d and 313d are narrower than the lateral widths of the top ends 311a and 314a of the connector terminals 311 and 314 (w2, w3 < w1, w4), and the cross-sectional areas are also reduced.

[0041] As shown in Figure 7As shown, the circuit chamber 235 includes a first side wall surface 235a, a second side wall surface 235b, and a third side wall surface 235c. The first side wall surface 235a vertically descends from the front surface 221 of the housing 201 toward the back side. The second side wall surface 235b is continuous with the lower end of the first side wall surface 235a and is inclined in a manner that gradually moves toward the center of the circuit chamber 235 as it moves toward the back side of the housing 201. The third side wall surface 235c is continuous with the lower end of the second side wall surface 235b and descends toward the back side of the housing 201 at an angle perpendicular to the front surface 221. These side wall surfaces are provided to be continuous around the circuit chamber 235. The second side wall surface 235b constitutes an inclined surface that is inclined in a direction that moves along the top ends 312a and 313a as it moves from the front surface 221 of the measuring part 201m toward the direction close to the top ends 312a and 313a.

[0042] The specific dimensions of the second side wall surface 235b in this embodiment are: the protrusion from the first side wall surface 235a to the third side wall surface 235c is 1.50 mm, the height from the lower end of the first side wall surface 235a to the upper end of the third side wall surface 235c is 1.58 mm, and the inclination angle of the top end portion 311a relative to the exposed surface is 62° [deg].

[0043] The base end of the second side wall surface 235b is arranged at a position corresponding to the contraction portion 312d, 313d of the connector terminals 312, 313. That is, the contraction portion 312d, 313d of the connector terminals 312, 313 is arranged at a position substantially the same as the first side wall surface 235a of the circuit chamber 235, and more specifically, is arranged at a position buried in the side wall surface of the circuit chamber 235 by δ1 compared to the first side wall surface 235a of the circuit chamber 235, that is, is arranged at a position entering into the molded resin portion of the measuring portion 201m constituting the housing 201. The top end portions 312a, 313a of the connector terminals 312, 313 have a length L1 from the contraction portion 312d, 313d to the top end, wherein a portion of the length L3 protrudes from the third side wall surface 235c of the circuit chamber 235 and is exposed in the circuit chamber 235 (refer to Figure 4 ).

[0044] Furthermore, the portion having a length of L2 is embedded in the molded resin portion of the measuring portion 201m relative to the third side wall surface 235c. The portion having a length of L2 is covered by the inclined second side wall surface 235b and becomes thinner as it moves toward the top end. The specific dimension of the length L2 in this embodiment is 1.90 mm.

[0045] The physical quantity measuring device 20 has a configuration in which the cross-sectional area of ​​the top end portions 312a and 313a of the intermediate connector terminals 312 and 313 disposed between the connector terminals 311 and 314 is smaller than the cross-sectional area of ​​the top end portions 311a and 314a of the connector terminals 311 and 314 on both sides. Therefore, the thermal stress generated at the interface between the connector terminals 312 and 313 and the sealing material 211 due to the temperature change of the device can be reduced, and the maximum principal stress acting on the sealing material 211 from the connector terminals 312 and 313 can be reduced. As a result, the sealing material 211 can be suppressed from peeling off from the housing 201, and the wire 303 such as the welding wire can be prevented from being broken due to the peeling off of the sealing material 211.

[0046] In addition, the cross-sectional area of ​​the top ends 312a and 313a of the middle connector terminals 312 and 313 is reduced not only in the portion of the length L3 exposed in the circuit chamber 235, but also in the portion of the length L2 embedded in the side wall surface of the circuit chamber 235. Therefore, the thermal stress generated at the interface between the connector terminals 312 and 313 and the housing 201 due to the temperature change of the device can also be reduced.

[0047] Furthermore, the physical quantity measuring device 20 of the present embodiment has a configuration in which an inclined second side wall surface 235b is provided on the side wall surface of the circuit chamber 235. Furthermore, the contraction portions 312d and 313d of the connector terminals 312 and 313 are arranged at positions substantially equal to the boundary portion between the first side wall surface 235a and the second side wall surface 235b, and are embedded in the side wall surface of the circuit chamber 235 by only a length L2.

[0048] The thickness of the molded resin portion of the measuring portion 201m covering the portion of the top end 312a, 313a having a length of L2 becomes thinner as it moves toward the top end due to the inclined second side wall surface 235b. Therefore, the maximum principal stress acting on the interface between the side wall surface of the circuit chamber 235 and the sealing material 211 can be reduced, and the sealing material 211 can be further prevented from peeling off from the housing 201.

[0049] And, for example Figure 8 As shown in (1), in the physical quantity measuring device 20 of this embodiment, the contraction portion 312d has a pair of tapered inclined surfaces 312f and 312e in a manner that narrows both sides of the width direction of the top portion 312a. Therefore, compared with a right-angle step shape, it is possible to prevent stress from concentrating on the contraction portion 312d, and improve the durability of the resin around the connector terminals 312 and 313. In addition, as shown in FIG. Figure 8 As shown in (2), a configuration may be adopted in which only one side of the width direction of the top end portion 312a is narrowed to have a single tapered inclined surface 312g.

[0050] Fig. 9This is a diagram showing the injection direction of the molding resin in injection molding. As shown by arrow Inj in the figure, when the connector terminal 301 is insert-molded into the housing 201, the molded resin is injected into the cavity from the gate portion of the mold corresponding to the end face of the flange 201f, and the molded resin flows into the mold from a direction orthogonal to the extension direction of the connector terminal 301.

[0051] The connector terminal 301 has the following structure: the cross-sectional area of ​​the top end portions 311a and 314a of the connector terminals 311 and 314 on both sides is larger than the cross-sectional area of ​​the top end portions 312a and 313a of the connector terminals 312 and 313 arranged in the middle between the connector terminals 311 and 314. Therefore, the strength against the resin flow stress during insert molding can be ensured, and the connector terminal 301 can be prevented from being deformed by the flow of the molding resin, causing the adjacent connector terminals to contact each other.

[0052] In the above embodiment, the case where the connector terminals 311 and 314 have the same cross-sectional area is described as an example, but the cross-sectional area of ​​the connector terminal 314 far from the gate portion may be smaller than the cross-sectional area of ​​the connector terminal 311 near the gate portion. That is, the cross-sectional area of ​​the top end portion of the connector terminal 311 arranged on the upstream side of the injection direction of the molded resin of the molded housing 20 may be larger than the cross-sectional area of ​​the top end portion of the connector terminal 314 arranged on the downstream side of the flow direction. In this way, the strength against the resin flow stress during insert molding can be further ensured, and the connector terminal 301 can be prevented from being deformed due to the flow of the molded resin, causing the adjacent connector terminals to contact each other.

[0053] The embodiments of the present invention are described in detail above, but the present invention is not limited to the embodiments described above, and various design changes can be made within the scope of the gist of the present invention described in the claims. For example, the embodiments described above are described in detail to explain the present invention in an easy-to-understand manner, and are not necessarily limited to having all the described structures. In addition, a part of the structure of a certain embodiment can be replaced by a structure of another embodiment, and a structure of another embodiment can be added to a structure of a certain embodiment. Furthermore, for a part of the structure of each embodiment, other structures can be added, deleted, or replaced. Explanation of symbols

[0054] 20: physical quantity measuring device (circuit device), 201: shell (housing), 201m: measuring part, 207: circuit substrate, 211: sealing material, 221: front surface, 235: circuit chamber, 301, 311, 312, 313, 314: connector terminals (conductor sheets), 311a, 312a, 313a, 314a: top end, 302: terminal block, 321, 322, 323, 324: soldering pads.

Claims

1. A circuit device, characterized in that: have: A housing having an opening for a circuit chamber at a front side; Three or more conductor sheets, which are insert-molded in the housing and whose top ends are exposed in parallel in the circuit chamber; a circuit substrate housed in the circuit chamber; A wire connecting the three or more conductor sheets and the circuit substrate; and a sealing material filled in the circuit chamber, The cross-sectional area of ​​the top end portion of at least one of the three or more conductor pieces located in the middle is smaller than the cross-sectional areas of the top ends located at both ends in the arrangement direction.

2. The circuit arrangement according to claim 1, characterized in that A constriction portion is provided at the distal end portion of at least one of the intermediate portions, the constriction portion reducing the cross-sectional area from a portion exposed in the circuit chamber to a position buried in the housing by a predetermined length closer to the proximal side than the side wall surface of the circuit chamber.

3. The circuit arrangement according to claim 2, characterized in that The cross-sectional area of ​​the portion of the at least one distal end portion located in the middle and located on the proximal side with respect to the constricted portion is equal to the cross-sectional areas of the distal ends located at both ends in the arrangement direction.

4. The circuit arrangement according to claim 1, characterized in that The side wall surface of the circuit chamber has an inclined surface that is inclined in a direction moving along the tip portion as moving from the front surface of the housing toward the tip portion.

5. The circuit arrangement according to claim 4, characterized in that The base end of the inclined surface is arranged at a position corresponding to the constricted portion.

6. The circuit arrangement according to claim 1, characterized in that The sealing material is formed of a thermosetting adhesive.

7. The circuit arrangement according to claim 1, characterized in that The sealing material is formed by an epoxy adhesive.

8. The circuit arrangement according to claim 1, characterized in that The cross-sectional area of ​​the tip of the three or more conductor pieces arranged on the upstream side in the injection direction of the molding resin for molding the housing is larger than the cross-sectional area of ​​the tip of the conductor piece arranged on the downstream side in the flow direction.

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