Pressure sensor

Abstract

A pressure sensor is provided with: a pressure detection unit having: a pressure chamber; a semiconductor sensor chip that detects the pressure of the fluid introduced into the pressure chamber; and a pin which is connected to the semiconductor sensor chip and constitutes an external input / output terminal of the semiconductor sensor chip. And a signal transmission unit having: a connector housing which is adjacent to the pressure detection unit and which is provided with a substrate accommodating unit, a connector connecting unit, and a partition wall unit defined between the substrate accommodating unit and the connector connecting unit; a connection terminal for performing signal connection with the outside; a conversion substrate which is accommodated in the substrate accommodating part and performs signal adjustment between the conversion substrate and the pressure detection part via the pins and signal adjustment between the conversion substrate and the outside via the connection terminals; and a heat-generating component which is attached to the conversion substrate and is fixed to the connector housing by a heat-dissipating adhesive, the heat-dissipating adhesive being disposed across an adhesive accumulation region which is a region extending in a direction orthogonal to a direction in which the signal transmission unit and the pressure detection unit are adjacent to each other, and the heat-generating component being attached to the conversion substrate and being fixed to the connector housing by means of a heat-dissipating adhesive, the heat-dissipating adhesive being disposed across the adhesive accumulation region and the adhesive accumulation region being a region extending in a direction orthogonal to a direction in which the signal transmission unit and the pressure detection unit are adjacent to each other.

Description

Technical Field

[0001] The present invention relates to a pressure sensor having a conversion substrate arranged therein. Background Art

[0002] Conventionally, in order to adapt to various drive voltages and pressure detection signal signal formats, there is a pressure sensor that externally connects a conversion substrate having a conversion circuit that converts both the drive voltage and the pressure detection signal between a control circuit and the pressure sensor.

[0003] In such a pressure sensor, in order to solve problems such as poor connection caused by external impact, vibration, etc., the cable is sometimes omitted and the conversion substrate is arranged inside the pressure sensor. However, the conversion substrate generates heat due to the transformation of the driving voltage, etc. Therefore, when the conversion substrate is arranged inside the pressure sensor, it is desired to efficiently dissipate the heat generated by the conversion substrate and suppress the heat transferred to the conversion substrate. If these are not effectively implemented, problems such as the electronic components in the conversion substrate exceeding the heat resistance temperature may occur.

[0004] As a structure for suppressing heat transfer to the conversion substrate, FIG10 of Patent Document 1 describes a structure in which a heat-conductive adhesive is used to surround heat-generating components such as transistors disposed near the conversion substrate, thereby efficiently dissipating heat from the heat-generating components to the outside and suppressing the influence of heat on the conversion substrate.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: International Publication No. 2022 / 097437 Summary of the invention

[0008] Problems to be solved by the invention

[0009] However, in the above structure described in Patent Document 1, during the process of manufacturing the pressure sensor, a heat generating component such as a transistor is sometimes inserted into the pre-filled adhesive, and the adhesive may overflow and contact the conversion substrate. If the adhesive spreads to the conversion substrate, especially the pad portion for soldering, defects may occur in the soldering portion on the upper surface of the substrate. In addition, if the adhesive bridges the conversion substrate and the heat generating component, the heat transfer between the heat generating component and the substrate cannot suppress the influence of heat.

[0010] An object of the present invention is to provide a pressure sensor capable of preventing a heat-dissipating adhesive from coming into contact with a conversion substrate.

[0011] Means for solving problems

[0012] In order to solve the above-mentioned problems, a pressure sensor is characterized in that it comprises: a pressure detecting portion having: a pressure chamber; a semiconductor sensor chip, which detects the pressure of a fluid introduced into the pressure chamber; and a pin, which is connected to the semiconductor sensor chip and constitutes an external input / output terminal of the semiconductor sensor chip; and a signal sending portion having: a connector housing, which is adjacent to the pressure detecting portion and has a substrate accommodating portion, a connector connecting portion and a partition portion defined between the substrate accommodating portion and the connector connecting portion; a connecting terminal, which is used to connect a signal to the outside; a conversion substrate, which is accommodated in the substrate accommodating portion and adjusts the signal between the pressure detecting portion via the pin and the signal between the outside via the connecting terminal; and a heat generating component, which is mounted on the conversion substrate and fixed to the connector housing by a heat-dissipating adhesive, and the heat-dissipating adhesive is arranged throughout an adhesive accumulation area, and the adhesive accumulation area is an area extending in a direction orthogonal to a direction adjacent to the signal sending portion and the pressure detecting portion.

[0013] In the above-mentioned pressure sensor, the conversion substrate may have a chamfered portion on a portion of an outer periphery of the conversion substrate, and the connector housing may have a substrate rotation preventing portion corresponding to the chamfered portion.

[0014] In addition, the above-mentioned pressure sensor may also be that the conversion substrate has a cutout arranged near the pad portion on the conversion substrate so as to prevent the heat-dissipating adhesive that bulges and expands in a direction orthogonal to the direction adjacent to the signal sending portion and the pressure detection portion from adhering to the pad portion on the conversion substrate when the heat-generating component is inserted into the adhesive accumulation area.

[0015] Effects of the Invention

[0016] According to the present invention, it is possible to provide a pressure sensor capable of preventing a heat-dissipating adhesive from coming into contact with a conversion substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a cross-sectional view showing a pressure sensor according to an embodiment of the present invention.

[0018] Figure 2 is a schematic diagram showing a pressure sensor body according to an embodiment of the present invention, Figure 2 (a) is a perspective view showing the pressure sensor body before the substrate is installed. Figure 2 (b) is a plan view showing the pressure sensor body after the adhesive is applied before the substrate is set.

[0019] Figure 3FIG. 1 is a partially enlarged cross-sectional view showing an adhesive reservoir region of a pressure sensor body according to an embodiment of the present invention. Figure 3 (a) is to Figure 2 (b) is a top view of the adhesive pooling area before the heat generating component is inserted, showing an enlarged view of part IIIa. Figure 3 (b) is a cross-sectional view of the adhesive pooling area before the heat generating component is inserted. Figure 3 (c) is a cross-sectional view of the adhesive pooling area after the heat generating component is inserted.

[0020] Figure 4 is a schematic diagram showing a pressure sensor body according to an embodiment of the present invention, Figure 4 (a) is a perspective view showing the pressure sensor body after the substrate is installed. Figure 4 (b) is a plan view showing the pressure sensor body after the substrate is installed.

[0021] Figure 5 (a) is a cross-sectional view showing a pressure sensor according to another embodiment of the present invention, Figure 5 (b) is a cross-sectional view showing a pressure sensor according to still another embodiment of the present invention.

[0022] Figure 6 It is a cross-sectional view showing a pressure sensor according to still another embodiment of the present invention. DETAILED DESCRIPTION

[0023] Reference Figures 1 to 6 The embodiment of the present invention will be described in detail. However, the present invention is not limited to the embodiment.

[0024] The pressure sensor 100 according to the embodiment of the present invention is provided with a heat dissipation unit for dissipating heat from the conversion substrate 133 and a heat transfer suppression unit to the conversion substrate 133, so that the heat generated in the conversion substrate 133 can be effectively dissipated to the external environment and the heat transfer from the fluid of the pressure detection object to the conversion substrate 133 can be suppressed. Here, the heat dissipation unit of the conversion substrate makes the conversion substrate 133 (including the heat generating component) indirectly thermally contact with the connector housing 131. Therefore, as the heat dissipation unit of the conversion substrate 133, the case where the conversion substrate 133 is indirectly thermally contacted with the connector housing 131 is described.

[0025] <Term>

[0026] In the description of this specification and claims, “one end” and “the other end” mean the “lower end” and “upper end” in the drawings.

[0027] <Structure of pressure sensor>

[0028] use Figure 1A pressure sensor 100 according to an embodiment of the present invention will be described.

[0029] The pressure sensor 100 is composed of a fluid introduction part 110, a pressure detection part 120, a signal sending part (main body) 130, and a connecting part 140. The following describes the respective structures of the pressure sensor 100 in turn. In addition, after the fluid introduction part 110 and the pressure detection part 120 are joined and fixed and the pressure detection part 120 and the signal sending part 130 are electrically connected, the fluid introduction part 110, the pressure detection part 120, and the signal sending part 130 are assembled into one body by the connecting part 140.

[0030] <Fluid Inlet Section>

[0031] The fluid introduction portion 110 is a member for introducing a fluid subjected to pressure detection into a pressure chamber 112A described later, and includes a metal joint member 111 and a metal bottom plate 112 connected to the other end of the joint member 111 by welding or the like.

[0032] The joint component 111 includes an internal threaded portion 111a connected to a pipe (not shown) for introducing a fluid for pressure detection, and a port 111b for guiding the fluid introduced from the pipe to the pressure chamber 112A. The open end of the port 111b is connected to an opening provided in the center of the bottom plate 112 by welding or the like. In the present embodiment, the joint component 111 includes the internal threaded portion 111a, but is not limited thereto, and may include an external threaded portion, or may be connected to a copper connection pipe instead of the joint component 111.

[0033] The bottom plate 112 has a bowl shape that increases in diameter from one end toward the other end in the radial direction relative to the central axis C of the pressure sensor 100 , and forms a pressure chamber 112A between the bottom plate 112 and a diaphragm 122 to be described later.

[0034] <Pressure Detection Section>

[0035] The pressure detection unit 120 detects the pressure of the fluid in the pressure chamber 112A, and includes: a housing 121 having a through hole; a diaphragm 122 that divides the pressure chamber 112A and a liquid seal chamber 124A described later; and a protective cover 123 disposed on the pressure chamber 112A side of the diaphragm 122. In addition, the pressure detection unit 120 includes: a sealing glass 124 that seals the inside of the through hole of the housing 121; the liquid seal chamber 124A filled with oil between the recessed portion on the pressure chamber 112A side of the sealing glass 124 and the diaphragm 122; and a support 125 disposed at the center of the sealing glass 124. In addition, the pressure detection unit 120 includes: a semiconductor sensor chip 126 that is supported by the support 125 and disposed inside the liquid seal chamber 124A; a potential adjustment member 127 disposed around the liquid seal chamber 124A; a plurality of pins 128 fixed to the sealing glass 124; and an oil filling tube 129 fixed to the sealing glass 124.

[0036] In order to maintain the strength around the sealing glass 124, the housing 121 is formed of a metal material such as an Fe·Ni alloy or stainless steel. The diaphragm 122 and the protective cover 123 are both formed of a metal material, and are both welded to the outer peripheral edge of the through hole on the pressure chamber 112A side of the housing 121. The protective cover 123 is arranged inside the pressure chamber 112A to protect the diaphragm 122, and is provided with a plurality of connecting holes 123a for the fluid introduced from the fluid inlet part 110 to pass through. After the pressure detection part 120 is assembled, the housing 121 is welded from the outside to the outer peripheral edge of the bottom plate 112 of the fluid inlet part 110 by TIG welding, plasma welding, laser welding, etc.

[0037] The sealing glass 124 is provided to protect the liquid-sealed chamber 124A in which the semiconductor sensor chip 126 is sealed from the surrounding environmental conditions such as moisture, dust, and heat in the air, to hold the plurality of pins 128, and to insulate the plurality of pins 128 from the housing 121. The semiconductor sensor chip 126 is supported on the liquid-sealed chamber 124A side of the pillar 125 disposed in the center of the sealing glass 124 by an adhesive or the like. In addition, in the present embodiment, the pillar 125 is formed of an Fe·Ni alloy, but is not limited thereto. For example, it may be formed of other metal materials such as stainless steel, or it may be configured so that the pillar 125 is not provided and the semiconductor sensor chip 126 is directly supported on the flat surface of the sealing glass 124 forming the recess.

[0038] The semiconductor sensor chip 126 includes: a diaphragm made of a material having a piezoresistive effect (e.g., single crystal silicon, etc.); a plurality of semiconductor strain gauges formed on the diaphragm, and an amplifier circuit for processing a bridge circuit formed by bridging these semiconductor strain gauges and an output from the bridge circuit; and an integrated circuit such as an arithmetic processing circuit. In addition, the semiconductor sensor chip 126 is connected to a plurality of pins 128, for example, by bonding wires 126a made of gold or aluminum, and the plurality of pins 128 constitute external input and output terminals of the semiconductor sensor chip 126.

[0039] The potential adjustment component 127 is provided to place the semiconductor sensor chip 126 in an electric field-free (zero potential) environment so that the circuits in the chip are not adversely affected by the potential generated between the frame ground terminal and the secondary power supply. The potential adjustment component 127 is disposed between the semiconductor sensor chip 126 and the diaphragm 122 in the liquid seal chamber 124A, is formed of a conductive material such as metal, and is connected to the terminal of the semiconductor sensor chip 126 connected to the zero potential.

[0040] The plurality of pins 128 and the oil filling tube 129 are fixed to the sealing glass 124 in a through-state by a sealing process. In this embodiment, a total of eight pins 128 are provided as the pins 128. That is, three pins 128 are provided for external output (Vout), drive voltage supply (Vcc), and grounding (GND), and five pins 128 are provided as terminals for adjusting the semiconductor sensor chip 126. Figure 1 , 4 of the 8 pins 128 are shown.

[0041] The oil filling pipe 129 is provided for filling the inside of the liquid seal chamber 124A with oil (for example, silicone oil or fluorine-based inert liquid, etc.). Figure 1 As shown, the other end of the oil filling tube 129 is crushed and sealed after being filled with oil.

[0042] <Operation of the Pressure Detection Unit>

[0043] The operation of the pressure detection unit 120 will be described. First, the diaphragm 122 is pressed by the fluid introduced from the joint component 111 into the pressure chamber 112A. The pressure applied to the diaphragm 122 by the pressure chamber 112A is transmitted to the semiconductor sensor chip 126 via the sealed oil in the liquid seal chamber 124A. The silicon diaphragm of the semiconductor sensor chip 126 is deformed by the transmitted pressure, and the pressure is converted into an electrical signal through a bridge circuit formed by a piezoresistance element, and is output from the integrated circuit of the semiconductor sensor chip 126 to the signal sending unit 130 via the bonding wire 126a and the plurality of pins 128.

[0044] <Signal sending unit>

[0045] The signal sending unit (main body) 130 sends the pressure signal detected by the pressure detection unit 120 to the outside, and includes a connector housing 131 for external connection arranged adjacent to the other end side of the pressure detection unit 120 and a flexible wiring material 132 whose one end is connected to the plurality of pins 128. In addition, the signal sending unit 130 includes a conversion substrate 133 fixed to the connector housing 131 via three connection terminals and the above-mentioned connection terminals 134a to 134c whose one end is connected to the conversion substrate 133. In addition, in order to avoid interference with the oil filling tube 129, an opening 133f is formed in the conversion substrate 133.

[0046] The connector housing 131 is formed of an insulating resin having a relatively high thermal conductivity, and includes a substrate housing portion 131a having a concave shape at one end, a connector connection portion 131b having a concave shape at the other end and connected to an external connector (not shown), and a partition wall portion 131c disposed between the substrate housing portion 131a and the connector connection portion 131b. A plurality of pins 128 extending from the sealing glass 124, an oil filling tube 129, a flexible wiring material 132, a conversion substrate 133, and the like are disposed in an internal space S defined by the substrate housing portion 131a.

[0047] In order to cope with the signal forms of the driving voltage and the pressure detection signal, the conversion substrate 133 includes a conversion circuit (not shown) for converting both the driving voltage and the pressure detection signal. The conversion circuit includes: a step-down circuit unit (not shown) that steps down the driving voltage (e.g., 8V to 36V) of the control circuit (not shown) connected to the outside of the pressure sensor 100 via the connection terminals 134a to 134c to the driving voltage (e.g., 5.0V) of the semiconductor sensor chip 126; and a voltage conversion circuit unit (not shown) that steps up the pressure detection signal (e.g., 0.5V to 4.5V) of the pressure sensor 100 to the pressure detection signal (e.g., 1V to 5V) of the control circuit. In this way, by appropriately selecting the conversion substrate 133 provided in the pressure sensor 100 in accordance with the signal forms of the driving voltage and the pressure detection signal, the difference between the driving voltage and the pressure detection signal can be absorbed without changing the design of the peripheral structures of the pressure detection unit 120, especially the semiconductor sensor chip 126 and the liquid seal chamber 124A.

[0048] The connection terminals 134a to 134c are provided with at least three for external output (Vout), driving voltage supply (Vcc), and grounding (GND). In order to improve the assembly performance, for the connection terminals 134a to 134c, for example, the connection terminal 134a is described, and one end 134d of the connection terminal 134a is inserted into the through hole provided in the conversion substrate 133, and the through portion is soldered, so that the connection terminal 134a is connected to the conversion substrate 133. A pad portion 133n is formed at the connection portion of the conversion substrate 133, and is connected to the electrode 135 through a conductive pattern. On the other hand, the other end side of the connection terminal 134a penetrates the partition wall portion 131c and extends to the connector connection portion 131b. The through portion of the partition wall portion 131c penetrated by the connection terminals 134a to 134c is sealed by the connection terminal fixing adhesive 134g.

[0049] <Connection Parts>

[0050] The connection member 140 includes a rivet plate 141 that connects and fixes the fluid introduction part 110 , the pressure detection part 120 , and the signal sending part 130 by rivet processing, and an adhesive sheet 142 that is arranged between the pressure detection part 120 and the signal sending part 130 .

[0051] The riveted plate 141 is formed into a cylindrical shape by a metal such as copper. The riveted plate 141 is arranged around the fluid inlet 110, the pressure detection unit 120 and the signal sending unit 130, and is fixed to the fluid inlet 110 and the signal sending unit 130 by riveting. By the riveting, the adhesive sheet 142 is clamped between the pressure detection unit 120 and the signal sending unit 130 to achieve waterproof and dustproof functions. In addition, between the adhesive sheet 142 and the housing 121, a non-metallic resin sheet 151 with heat radiation and an adhesive 152 with heat radiation can be clamped as a heat transfer suppression unit to the conversion substrate 133.

[0052] <Conversion substrate heat dissipation unit>

[0053] The conversion substrate 133 has another end face 133b on which various electronic components are mounted and separated from the connector housing 131, and one end face 133a on which connection terminals 134a to 134c are welded. The heat generating component 133h (for example, a transistor, a regulator, etc.) in this embodiment is a lead type and is mounted on the other end face 133b. The conversion substrate 133 generates heat by itself due to the transformation of the driving voltage, etc., so if no countermeasures are taken for this, the electronic components on the conversion substrate may exceed the heat-resistant temperature and be damaged. Therefore, in this embodiment, in order to prevent the electronic components of the conversion substrate 133 from exceeding the heat-resistant temperature, various heat dissipation units of the conversion substrate 133 are adopted. As a result, the heat generated in the conversion substrate 133 can be efficiently dissipated to the external environment, so the margin relative to the heat-resistant temperature of the conversion substrate 133 can be increased. Below, the heat dissipation unit of the conversion substrate 133 in this embodiment is specifically described.

[0054] <Conversion substrate heat dissipation unit (lead-type heat generating component)>

[0055] As the heat dissipation unit of the conversion substrate 133, a lead-type heat generating component 133h is used to form Figure 1 The heat dissipation path with a dotted line (1) in the figure. The lead-type heat generating component 133h is arranged on the side of the substrate opposing surface 131a1. Since the heat generating component 133h is filled with a heat dissipating adhesive 133g having thermal conductivity, in order to prevent the heat dissipating adhesive 133g from spreading onto the conversion substrate, an adhesive storage wall 131w that defines an adhesive storage area 131e is provided between the outer periphery of the connector housing 131. That is, in the present embodiment, the adhesive storage area 131e is defined by the adhesive storage wall 131w and the substrate accommodating portion 131a and the partition portion 131c of the main body 130. The lead-type heat generating component 133h is accommodated in the adhesive storage area 131e, and the heat dissipating adhesive 133g having thermal conductivity is filled only between the adhesive storage area 131e and the lead-type heat generating component 133h. Thus, in this embodiment, the heat generated in the heat generating component 133h is actively transferred to the heat dissipating adhesive 133g having thermal conductivity surrounding the heat generating component 133h, so that the heat can be more efficiently dissipated to the external environment through the connector housing 131. Figure 2 As shown in FIG. 2( b), it is preferred that the adhesive reservoir area 131e surrounded by the adhesive reservoir wall surface 131w and the inner wall of the connector housing 131 is arranged along a direction ( Figure 2(b) is formed in the front direction, rear direction, left direction, and right direction when viewed from above. This is because, compared to a shape formed by connecting the intersection of the adhesive storage wall 131w and the inner wall of the connector housing 131 with the shortest distance, or a shape formed by connecting the two ends of the adhesive storage wall 131w with a gentle curve (for example, an arc shape), by having a rectangular shape when viewed from above as in the present embodiment, the surface area of ​​the adhesive storage area 131e can be increased. As a result, the amount of heat generated in the heat generating component 133h that moves to the heat-conductive heat-dissipating adhesive 133g surrounding the heat generating component 133h can be further increased. In addition, as Figure 2 As shown in (b), by forming the top view rectangular shape in a manner avoiding the connection terminals 134b and 134c, the space can also be used effectively. In addition, the lead-type heat-generating component 133h is mounted on the conversion substrate 133 via the lead 133l, so that the heat-generating portion of the heat-generating component 133h is physically separated from the conversion substrate 133, thereby preventing the electronic components of the conversion substrate 133 from exceeding the heat-resistant temperature.

[0056] Here, the lead-type heat generating component 133h is provided close to the outside air on the outer diameter side of the connector housing 131. Thus, the heat dissipating adhesive 133g filled around the lead-type heat generating component 133h can dissipate heat to the outside of the connector housing 131 more easily.

[0057] Furthermore, by providing a space between the heat dissipating adhesive 133 g filling the periphery of the lead-type heat generating component 133 h and the conversion substrate 133 , heat transfer between the heat generating component 133 h and the conversion substrate 133 can be suppressed.

[0058] <Heat transfer suppression unit>

[0059] The fluid to be detected by the pressure is introduced into the pressure chamber 112A. However, depending on the use conditions of the fluid, a very high temperature (e.g., about 130°C) fluid may be introduced to serve as a heat source. In this case, the heat of the pressure detection unit 120 (heat of the high temperature fluid introduced into the pressure chamber 112A, etc.) is transferred to the conversion substrate 133 (from the Figure 1The heat transfer, heat conduction and heat radiation (radiation) from one end side to the other end side of the pressure detection part 120 may be offset by the heat dissipation effect of the heat dissipation unit (lead-type heat-generating component). Therefore, in the present embodiment, various heat movement suppression units are used to prevent the heat on the pressure detection part 120 side (heat from the high-temperature fluid introduced into the pressure chamber 112A, etc.) from being transferred to the conversion substrate 133. Therefore, in the present embodiment, it is possible to suppress the heat on the pressure detection part 120 side from being transferred to the conversion substrate 133, so that the heat dissipation effect of the heat dissipation unit (lead-type heat-generating component) can be fully exerted. The heat movement suppression unit to the conversion substrate 133 in the present embodiment will be specifically described below.

[0060] <First Heat Transfer Suppression Unit to Conversion Substrate (Internal Space)>

[0061] The internal space S is used as a first heat transfer suppression unit to the conversion substrate 133. Specifically, by arranging the conversion substrate 133 near the other end of the substrate receiving portion 131a, the distance L in the direction of the central axis C between the conversion substrate 133 and the housing 121 on the pressure detection portion 120 side in the internal space S can be set as large as possible. Thus, in this embodiment, the heat on the pressure detection portion 120 side passes through the internal space S of the air having a long heat transfer path and low thermal conductivity, and thus the heat transfer to the conversion substrate 133 can be suppressed. However, the conversion substrate 133 is not in direct contact with the other end of the substrate receiving portion 131a as described in the next item.

[0062] <Second Heat Transfer Suppression Unit to Conversion Substrate (Separation of Conversion Substrate and Main Body)>

[0063] like Figure 1 As shown, the conversion substrate 133 is separated from the other end and the outer periphery of the substrate receiving portion 131a in a manner that does not directly contact the connector housing 131. Instead of being directly supported by the connector housing 131, the conversion substrate 133 is Figure 4 As shown in (a) and (b), the three connection terminals 134a to 134c are supported at three points. The three connection terminals 134a to 134c are arranged to be located at the center side of the conversion substrate 133 where a load is applied when the connection terminals 134a to 134c are welded to the conversion substrate 133. Figure 1As shown, the three connecting terminals 134a to 134c are not of a straight structure, but of a structure with a step 134f, and the conversion substrate 133 can be supported by the step 134f. The position of the step 134f is set to a height that does not contact the connector housing 131 when the conversion substrate 133 is accommodated in the connector housing 131, so that the conversion substrate 133 is supported at three points as described above. By setting such a structure, the conversion substrate 133 is configured so that even if a load is applied during welding, it is difficult to tilt relative to the connecting terminals 134a to 134c and can be arranged in a well-balanced manner, and the movement of the conversion substrate 133 in the direction of the connector housing 131 (upward direction) is suppressed, and it is firmly supported by the connecting terminals 134a to 134c. And, as Figure 1 As shown, the connection terminals 134a to 134c themselves are fixed to the connector housing 131 by the connection terminal fixing adhesive 134g, and the lead-type heat generating component 133h mounted on the conversion substrate 133 is fixed to the connector housing 131 by the heat dissipating adhesive 133g, thereby indirectly fixing the conversion substrate 133 to the connector housing 131. In this way, the conversion substrate 133 is separated from the other end of the substrate accommodating portion 131a in a manner that does not directly contact the connector housing 131, so that the heat transferred from the lead-type heat generating component 133h to the surrounding heat dissipating adhesive 133g can be suppressed from being transferred to the conversion substrate 133.

[0064] In addition, the conversion substrate 133 is provided in a manner that its side portion is separated from the outer periphery of the substrate accommodation portion 131a, thereby preventing stress from being applied to the conversion substrate 133 from the connector housing 131 due to the difference in linear expansion coefficient caused by heat between the conversion substrate 133 and the connector housing 131. Thus, damage to the conversion substrate 133 caused by the stress applied to the conversion substrate 133 from the connector housing 131 due to the difference in linear expansion coefficient can be prevented.

[0065] <Third Heat Transfer Suppression Mechanism to Conversion Substrate (Flexible Wiring Material)>

[0066] The flexible wiring material 132 is used as a third heat transfer suppression unit to the conversion substrate 133. Specifically, the flexible wiring material 132 is formed of, for example, a flexible printed circuit board (FPC) having flexibility, a thin plate-shaped conductive component, a lead monomer, a collection of leads, etc., and connects the plurality of pins 128 and the electrode 135 in a bent or folded state in the internal space S. Therefore, the connection distance between the plurality of pins 128 and the electrode 135 can be set to be relatively large. In addition, the flexible wiring material 132 is thinner than ordinary wiring materials and has a small cross-sectional area. Therefore, in this embodiment, the heat on the semiconductor sensor chip 126 side passes through the flexible wiring material 132 with a long heat transfer path and a small cross-sectional area, so that the heat transfer to the conversion substrate 133 can be suppressed.

[0067] <Main body assembly process>

[0068] Figure 2 (a) is a perspective view of the main body 130 before the conversion substrate 133 is provided on the main body 130, before the connection terminal fixing adhesive 134g is applied, and before the heat dissipating adhesive 133g is filled in the adhesive reservoir area 131e. Figure 2 (b) is a plan view of the main body 130 before the conversion substrate 133 is provided on the main body 130, after the connection terminal fixing adhesive 134g is applied, and after the heat dissipating adhesive 133g is filled in the adhesive reservoir area 131e. Figure 2 (a) A portion of the connector housing 131 is cut away so that the inside of the main body can be seen. Figure 4 The same is true in (a).

[0069] In the assembly process of the main body 130, first, Figure 2 As shown in (a), three connection terminals 134a to 134c are inserted into the main body 130. Then, as shown in Figure 1 as well as Figure 2 As shown in (b), the connection terminal fixing adhesive 134g is applied (filled) around the connection terminals 134a to 134c so that the inserted connection terminals 134a to 134c are fixed to the main body 130. However, the thickness of the application is determined so that the connection terminal fixing adhesive 134g does not adhere to the conversion substrate 133. Figure 1 as well as Figure 2 As shown in (b), the heat dissipating adhesive 133g is filled in the adhesive storage area 131e of the main body 130. However, the heat dissipating adhesive 133g is filled to about half to 80% of the fillable space volume of the adhesive storage area 131e, and is not filled to the limit of the fillable volume. Then, the conversion substrate 133 is inserted into the main body 130. At this time, the lead-type heat generating component 133h is pre-assembled on the conversion substrate 133 and protrudes to the substrate opposing surface 131a1 side, so it is inserted into the heat dissipating adhesive 133g filled in the adhesive storage area 131e of the main body 130. Next, the main body 130 with the conversion substrate 133 inserted is placed in an oven and heated to cure the heat dissipating adhesive 133g and the connection terminal fixing adhesive 134g. This heating is for the purpose of preventing migration caused by moisture absorption of the conversion substrate 133, and also for the purpose of drying the conversion substrate 133. Then, the connection terminals 134a to 134c and the lead-type heat generating component 133h are soldered to the conversion substrate 133. Finally, a solder inspection is performed to confirm whether soldering is performed properly.

[0070] <Inserting lead-type heat-generating components into heat-dissipating adhesive>

[0071] Figure 3 (a) is to Figure 2 (b) is an enlarged view of part IIIa surrounded by a quadrilateral. Figure 3 (b) is shown in Figure 3 (a) is a side cross-sectional view showing a state where a lead-type heat generating component 133h is inserted into the insertion region 133i, Figure 3 (c) is a side cross-sectional view showing swelling of the heat dissipating adhesive 133g after the lead-type heat generating component 133h is inserted into the insertion region 133i.

[0072] Figure 4 (a) is a perspective view of the main body 130 after the conversion substrate 133 is provided on the main body 130. Figure 4 (b) Viewed from the conversion substrate 133 side Figure 4 (a) Plan view of the main body.

[0073] In the above-mentioned main body assembly process, Figure 3 In the insertion area 133i of the heat dissipating adhesive 133g filled in the adhesive reservoir area 131e of the main body 130 shown in (a), it is possible to Figure 3 When the lead-type heat generating component 133h is inserted as shown in (b), Figure 3 As shown in (c), the heat dissipating adhesive 133g bulges along the surfaces of the lead-type heat generating component 133h. In this regard, if no countermeasures are taken, the bulging heat dissipating adhesive 133g may climb along the adhesive pool wall surface 131w due to surface tension ( Figure 2 (a) in the direction of arrow A shown in the figure), directly contacts the conversion substrate 133, or drips onto the conversion substrate 133. In particular, when the heat-dissipating adhesive 133g contacts the soldering portion (pad portion 133n) of the conversion substrate 133, poor soldering may occur. The heat-dissipating adhesive 133g is arranged throughout an adhesive storage area 131e that extends in a direction orthogonal to the direction adjacent to the signal sending portion 130 and the pressure detecting portion 120 of the lead-type heat-generating component 133h. This is to ensure that even if the lead-type heat-generating component 133h is inserted into the heat-dissipating adhesive 133g, the heat-dissipating adhesive 133g that bulges and extends in the direction orthogonal to the direction adjacent to the signal sending portion 130 and the pressure detecting portion 120 can be fully accommodated, thereby preventing the heat-dissipating adhesive 133g from adhering to the conversion substrate 133. In addition, the heat-dissipating adhesive 133g is arranged along the adhesive storage wall 131w, at Figure 2In the direction of arrow A shown in (a), a cutout portion 133k is provided at a portion of the conversion substrate 133 that may climb due to surface tension. As a result, the interval between the conversion substrate 133 and the inner wall of the main body 130 can be enlarged, and the heat dissipating adhesive 133g that bulges and expands in a direction orthogonal to the direction adjacent to the signal sending unit 130 and the pressure detecting unit 120 can be prevented from climbing along the adhesive storage wall surface 131w due to surface tension. In addition, by providing the cutout portion 133k near the pad portion 133n of the conversion substrate 133, even if the heat dissipating adhesive 133g overflowing in a direction orthogonal to the direction adjacent to the signal sending unit 130 and the pressure detecting unit 120 drips onto the substrate, it is possible to prevent the heat dissipating adhesive 133g from adhering to the pad portion 133n. In addition, in the present embodiment, the direction adjacent to the signal sending unit 130 and the pressure detecting unit 120 coincides with the direction in which the lead-type heat generating component 133h is mounted on the conversion substrate 133.

[0074] In addition, if Figure 2 (a) Figure 2 (b) and Figure 4 (a) Figure 4 As shown in (b), in the present embodiment, the opposing portions of the circular outer periphery of the conversion substrate 133 when viewed from above are chamfered at two locations and provided with chamfered portions 131m, and correspondingly, two substrate rotation stop portions 136 are provided on the circular inner wall when viewed from above of the main body 130. As a result, the circular inner wall of the main body 130 and the circular outer periphery of the conversion substrate 133 serve as guides, and the centers of the conversion substrate 133 and the main body 130 when viewed from above are aligned. In this way, by aligning the centers of the circular outer periphery of the conversion substrate 133 when viewed from above and the inner wall of the main body 130 when viewed from above, the shaking in the forward, backward, left, and right directions when viewed from above can be reduced. Furthermore, the chamfered portions 131m and the substrate rotation stop portions 136 are used to position and orient the conversion substrate 133. This is to prevent the heat-dissipating adhesive 133g from dripping onto the conversion substrate 133, and the conversion substrate 133 will not rotate relative to the main body 130 even when and after the conversion substrate 133 is inserted into the main body 130. As shown in FIG. Figure 4 (a) Figure 4As shown in (b), the chamfered portion 131m and the substrate rotation stopper 136 engage with each other, thereby serving as a guide when the conversion substrate 133 is inserted into the connector housing 131, and it is not necessary to rotate the conversion substrate 133 to find the insertion position in order to insert the three connection terminals 134a to 134c into the through holes of the three pad portions 133n. As a result, the swing of the liquid surface of the heat dissipating adhesive 133g caused by the rotation of the conversion substrate 133 relative to the main body 130 disappears, thereby preventing the heat dissipating adhesive 133g from dripping onto the conversion substrate 133 and spreading to the entire conversion substrate 133 along the inner circumference of the main body 130. In this embodiment, the chamfered portion 131m and the substrate rotation stopper 136 are formed in a linear shape, but are not limited to this. For example, they may be formed in a concave shape and a convex shape and engage with each other. Furthermore, one may have a cutout and the other may have a shape corresponding to the cutout, thereby obtaining the same effect as the chamfered portion 131m and the substrate rotation stopper 136 described above. In addition, the chamfered portion 131m and the substrate rotation stopper 136 are provided with two each, but one or more than three may be provided. In addition, when the outer periphery of the conversion substrate 133 when viewed from above and the inner wall of the main body 130 when viewed from above are rectangular, any shape that can be fitted or engaged with each other may be sufficient.

[0075] In addition to the above preventive measures, Figure 2 As shown in (b), by arranging the insertion area 133i for inserting the lead-type heat generating component 133h into the heat dissipating adhesive 133g at a position away from the outer peripheral wall surface of the main body 130, it is also possible to prevent the raised heat dissipating adhesive 133g from contacting the conversion substrate 133.

[0076] <Pressure sensor assembly process>

[0077] Next, the assembly process of the pressure sensor 100 is described. First, the pressure detection unit 120 and the above-mentioned signal sending unit (main body) 130 are assembled separately. Then, in the pressure detection unit 120, the sealed oil is filled into the liquid seal chamber 124A via the oil filling tube 129, and the oil filling tube 129 is closed. Furthermore, the fluid introduction unit 110 is fixed to the pressure detection unit 120 by welding or the like. Thereafter, the plurality of pins 128 of the pressure detection unit 120 and the conversion substrate 133 of the signal sending unit 130 are arranged in parallel so as to face upward, and one and the other of the flexible wiring materials 132 are fixed to the surfaces of the plurality of pins 128 and the electrode 135 on the conversion substrate 133, respectively. Furthermore, the pressure detection unit 120 and the signal sending unit 130 are arranged opposite to each other on the same axis via the bent or folded flexible wiring material 132, and the adhesive sheet 142 is sandwiched between the pressure detection unit 120 and the signal sending unit 130. Finally, one end and the other end of the rivet plate 141 are respectively engaged with the bottom plate 112 of the fluid inlet part 110 and the connector housing 131 of the signal sending part 130 , so that the fluid inlet part 110 , the pressure detection part 120 and the signal sending part 130 are fixed integrally.

[0078] Here, in the pressure sensor 100, when the bent or folded flexible wiring material 132 is not used, the assembly process of the pressure sensor 100 needs to be assembled in a stacked manner from one end side to the other end side in the direction of the central axis C, for example. Therefore, the degree of freedom of the assembly process is extremely low, and it is difficult to achieve a reduction in assembly time. However, in this embodiment, by connecting the pressure detection unit 120 and the signal sending unit 130 via the bent or folded flexible wiring material 132, the degree of freedom of the assembly process of the pressure sensor 100 can be increased, and thus the assembly time can be reduced.

[0079] <Other Implementation Methods>

[0080] Reference Figure 5 (a) Figure 5 (b) and Figure 6 Several other embodiments different from the above-mentioned embodiment will be described. In addition, the same reference numerals are attached to the same structures as those in the above-mentioned embodiment, and the description thereof will be omitted.

[0081] Figure 5 (a) is a cross-sectional view showing a pressure sensor according to another embodiment of the present invention, Figure 5 (b) is a cross-sectional view of a pressure sensor showing another embodiment of the present invention. Figure 5As shown in (a), in this embodiment, the conversion substrate 233 is arranged parallel to the central axis C, that is, in a direction parallel to the direction adjacent to the signal sending unit 130 and the pressure detection unit 120. In addition, the lead 2331 of the lead type heat generating component 233h is bent at a right angle, and the front end is inserted from the mounting surface 233b to the solder surface 233a through the through hole provided in the conversion substrate 233, and the through portion is soldered, thereby connecting the connection terminal 134a to the conversion substrate 233. A pad portion 233n is formed at the connection portion of the conversion substrate 233, and is electrically connected to the electrode 135 through a conductive pattern.

[0082] like Figure 5 As shown in (b), in another embodiment, the conversion substrate 333 is also arranged in a direction parallel to the direction adjacent to the signal sending unit 130 and the pressure detection unit 120. In addition, the lead 3331 of the lead-type heating component 333h is bent at a right angle, and its front end is bent into an L shape. The front end of the lead 3331 bent into an L shape is welded to the mounting surface 333b of the conversion substrate 333 to form a pad portion 333n.

[0083] Figure 6 FIG. 2 is a cross-sectional view showing a pressure sensor according to another embodiment of the present invention. Figure 6 As shown, in this embodiment, the conversion substrate 433 is also arranged in a direction parallel to the direction adjacent to the signal sending unit 130 and the pressure detection unit 120. In addition, the lead 4331 of the lead-type heating component 433h is parallel to the conversion substrate 433, and a part of the lead 4331 is attached to the pattern on the mounting surface 433b of the conversion substrate 433 by, for example, a conductive adhesive.

[0084] Thus, in other embodiments of the present invention, the conversion substrates 233, 333, 433 are arranged in the direction adjacent to the signal sending unit 130 and the pressure detecting unit 120, so the area of ​​the portion facing the adhesive reservoir area 131e is extremely small compared to the conversion substrate 133. Thus, the lead-type heat generating components 233h, 333h, 433h are respectively inserted into the adhesive reservoir area 131e, and even if the heat dissipating adhesive 133g swells and spreads in the direction orthogonal to the direction adjacent to the signal sending unit 130 and the pressure detecting unit 120, the heat dissipating adhesive 133g does not drip onto the conversion substrates 233, 333, 433. In addition, even if the heat dissipating adhesive 133g rises due to surface tension, the heat dissipating adhesive 133g can be prevented from dripping onto the conversion substrates 233, 333, 433. Furthermore, even if the heat-dissipating adhesive 133g overflows in a direction perpendicular to the direction in which the signal sending unit 130 and the pressure detecting unit 120 are adjacent, the heat-dissipating adhesive 133g can be prevented from adhering to the pad portion 233n or 333n.

[0085] According to the above-described configuration, it is possible to prevent soldering failure that occurs when a heat-dissipating adhesive is used in order to effectively dissipate heat generated in the conversion substrate to the external environment.

[0086] Explanation of symbols

[0087] 100: Pressure sensor

[0088] 110: Fluid inlet

[0089] 111: Connector parts

[0090] 112: Bottom plate

[0091] 120: Pressure detection unit

[0092] 121: Shell

[0093] 122: Diaphragm

[0094] 123: Protective cover

[0095] 124: Sealed glass

[0096] 124A: Liquid seal chamber

[0097] 125: Pillar

[0098] 126: Semiconductor sensor chip

[0099] 127: Potential adjustment component

[0100] 128: Pin

[0101] 129: Oil filling tube

[0102] 130: Signal sending unit (main body)

[0103] 131: Connector housing

[0104] 131a: substrate storage portion

[0105] 131a1: Substrate facing surface

[0106] 131b: Connector connection part

[0107] 131c: Next door

[0108] 131e: Adhesive accumulation area

[0109] 131m: Chamfering

[0110] 131w: Adhesive accumulation on the wall

[0111] 132: Flexible wiring material

[0112] 133: Conversion substrate

[0113] 133a: One end face

[0114] 133b: The other end

[0115] 133f: Opening

[0116] 133g: Heat dissipation adhesive

[0117] 133h: Heating components

[0118] 133i: Insertion area

[0119] 133k: Cutting part

[0120] 133l: Lead

[0121] 133n: pad part

[0122] 134a: Connecting terminal

[0123] 134b: Connecting terminal

[0124] 134c: Connecting terminal

[0125] 134d: One end

[0126] 134e: The other end

[0127] 134f: Stairs

[0128] 135: Electrode

[0129] 136: Base plate anti-rotation part

[0130] 140: Connecting parts

[0131] 141: Riveted plate

[0132] 142: Adhesive sheet

[0133] 151: Heat radiating resin sheet

[0134] 152: Adhesive with heat radiation

[0135] 233: Conversion substrate

[0136] 233a: Solder side

[0137] 233b: Mounting surface

[0138] 233n: pad part

[0139] 333: Conversion substrate

[0140] 333a: Solder side

[0141] 333b: Mounting surface

[0142] 333n: pad part

[0143] 433: Conversion substrate

[0144] 433a: Solder side

[0145] 433b: Mounting surface

[0146] A: Direction of heat dissipation adhesive climbing

[0147] C: Central axis

[0148] L: The distance between the conversion substrate and the central axis of the housing

[0149] S: Internal space

Claims

1. A pressure sensor, characterized in that: have: A pressure detection unit having: a pressure chamber; a semiconductor sensor chip that detects the pressure of a fluid introduced into the pressure chamber; and a pin that is connected to the semiconductor sensor chip and constitutes an external input / output terminal of the semiconductor sensor chip; and The signal sending part comprises: a connector housing adjacent to the pressure detecting part and provided with a substrate accommodating part, a connector connecting part and a partition wall defined between the substrate accommodating part and the connector connecting part; a connecting terminal for connecting a signal with the outside; a conversion substrate accommodated in the substrate accommodating part for adjusting a signal with the pressure detecting part via the pins and a signal with the outside via the connecting terminal; and a heat generating component mounted on the conversion substrate and fixed to the connector housing by a heat dissipating adhesive. The heat-dissipating adhesive is arranged over an adhesive pooling region that extends in a direction orthogonal to a direction in which the signal sending section and the pressure detecting section are adjacent.

2. The pressure sensor according to claim 1, characterized in that: The conversion substrate has a chamfered portion at a portion on an outer periphery of the conversion substrate, and the connector housing has a substrate rotation stopper portion in a manner corresponding to the chamfered portion.

3. The pressure sensor according to claim 1 or 2, characterized in that: The conversion substrate has a cutout arranged near the pad portion on the conversion substrate so as to prevent the heat-dissipating adhesive that bulges and expands in a direction orthogonal to a direction adjacent to the signal sending portion and the pressure detecting portion from adhering to the pad portion on the conversion substrate when the heat-generating component is inserted into the adhesive storage area.

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