pressure sensor

Abstract

To provide a pressure sensor that is provided with a conversion substrate inside the pressure sensor, and can prevent an increase in the outer diameter of the pressure sensor.SOLUTION: A pressure sensor comprises: a pressure detection unit having a pressure chamber, a semiconductor sensor chip that detects the pressure of fluid to be introduced into the pressure chamber, and a detection unit housing that accommodates the semiconductor sensor chip; and a signal transmission unit that is adjacent to the pressure detection unit and has a connection terminal and a connector housing. An upper end surface of the detection unit housing and a lower end surface of the connector housing compress a seal member to form a seal structure.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a pressure sensor having a conversion substrate provided therein, and more specifically to a sealing structure for a pressure sensor.

Background Art

[0002] Conventionally, in order to adapt to various signal systems of driving voltage and pressure detection signal, there is a type of pressure sensor in which a conversion substrate including a conversion circuit that converts both the driving voltage and the pressure detection signal is arranged inside the pressure sensor.

[0003] Regarding this internal arrangement, Patent Document 1 describes that a conversion substrate is arranged inside a pressure sensor, and an O-ring for sealing outside air is provided as a sealing structure.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problem to be Solved by the Invention

[0005] However, in a configuration where a conversion substrate is provided inside a pressure sensor, housing the conversion substrate inside tends to increase the outer diameter of the pressure sensor. In addition, the configuration provided with the O-ring described in Patent Document 1 requires an area for providing a groove for the O-ring, which further increases the outer diameter of the pressure sensor accordingly.

[0006] An object of the present invention is to provide a pressure sensor in which an increase in the outer diameter of the pressure sensor can be suppressed in a configuration where a conversion substrate is provided inside the pressure sensor.

Means for Solving the Problem

[0007] To solve the above problems, the present invention provides a pressure detection unit having a pressure chamber, a semiconductor sensor chip for detecting the pressure of a fluid introduced into the pressure chamber, and a detection unit housing for housing the semiconductor sensor chip, and a signal transmission unit adjacent to the pressure detection unit having a connection terminal and a connector housing, wherein a sealing structure is formed by compressing a sealing member between the upper end surface of the detection unit housing and the lower end surface of the connector housing.

[0008] Furthermore, in the above-mentioned pressure sensor, the signal transmission unit may further include a signal mediating board for connecting input and output signals with an external circuit.

[0009] Furthermore, in the above-mentioned pressure sensor, the signal mediating substrate may be a conversion substrate that converts the drive voltage supplied to the semiconductor sensor chip from the external circuit and / or the pressure detection signal detected by the semiconductor sensor chip into an output corresponding to the external circuit.

[0010] Furthermore, in the above-mentioned pressure sensor, the signal mediating substrate may also be a relay substrate that relays the drive voltage supplied to the semiconductor sensor chip from the external circuit and / or the pressure detection signal detected by the semiconductor sensor chip to the external circuit.

[0011] Furthermore, in the above-mentioned pressure sensor, the sealing member may consist of three layers: an upper layer, an intermediate layer, and a lower layer, and may have double-sided adhesive properties as the upper layer and the lower layer are adhesive.

[0012] Furthermore, the pressure sensor may also be provided with a crimping member that accommodates both the detection unit housing and the connector housing, and the pressure detection unit and the signal transmission unit may be compressed and fixed by crimping the end of the crimping member, thereby compressing the sealing member.

[0013] Furthermore, in the above-mentioned pressure sensor, an adhesive insulating sheet may be bonded to the upper end surface of the detection unit housing with an insulating adhesive, and the sealing member may be in close contact with the upper end surface of the detection unit housing via the insulating sheet.

[0014] Furthermore, in the above-mentioned pressure sensor, the sealing member may be made of butyl rubber.

[0015] To solve the above problems, the present invention provides a pressure detection unit having a pressure chamber, a semiconductor sensor chip for detecting the pressure of a fluid introduced into the pressure chamber, and a detection unit housing for housing the semiconductor sensor chip; a signal transmission unit adjacent to the pressure detection unit and having an upper cover; a waterproof case housing the pressure detection unit and the signal transmission unit; and a sealing material for sealing the pressure detection unit and the signal transmission unit inside the waterproof case, wherein the sealing structure is formed by compressing the sealing member between the upper end surface of the detection unit housing and the lower end surface of the upper cover.

[0016] Furthermore, in the above-described pressure sensor, the signal transmission unit may have a signal mediating board inside the upper cover for connecting input and output signals with an external circuit, and a board housing unit for housing the signal mediating board.

[0017] Furthermore, in the above-mentioned pressure sensor, the signal mediating substrate may be a conversion substrate that converts the drive voltage supplied to the semiconductor sensor chip from the external circuit and / or the pressure detection signal detected by the semiconductor sensor chip into an output corresponding to the external circuit.

[0018] Furthermore, the above-mentioned pressure sensor may also be a relay board that relays the drive voltage supplied from the external circuit to the semiconductor sensor chip and / or the pressure detection signal detected by the semiconductor sensor chip to the external circuit.

[0019] Furthermore, the pressure sensor may have double-sided adhesive properties, as the sealing member consists of three layers: an upper layer, an intermediate layer, and a lower layer, and the upper and lower layers are adhesive.

[0020] Further, in the pressure sensor, after filling the sealing material into the waterproof case, the detection portion housing and the upper cover may be held until the sealing material cures, so that the pressed state between the detection portion housing and the upper cover is maintained.

[0021] Further, in the pressure sensor, an adhesive insulating sheet may be adhered to an upper end surface of the detection portion housing by an insulating adhesive, and the sealing member may be in close contact with the upper end surface of the detection portion housing via the insulating sheet.

[0022] Further, in the pressure sensor, the sealing member may be made of butyl rubber. Effects of the Invention

[0023] In a configuration in which a conversion substrate is provided inside the pressure sensor, it is possible to provide a pressure sensor capable of suppressing an increase in the outer diameter of the pressure sensor. Brief Description of the Drawings

[0024] [Figure 1] FIG. 1 is a cross-sectional view showing a pressure sensor according to an embodiment of the present invention. [Figure 2] FIG. 2 is an enlarged cross-sectional view showing an outside air seal portion II in FIG. 1. [Figure 3] FIG. 3 is a schematic plan view showing a butyl rubber seal according to an embodiment of the present invention. [Figure 4] FIG. 4 is a schematic view showing a butyl rubber seal according to an embodiment of the present invention, wherein FIG. 4(a) is a perspective view showing a cross-section obtained by cutting the butyl rubber seal of FIG. 3 in half, and FIG. 4(b) is a cross-sectional view of part IVb in FIG. 4(a). [Figure 5] FIG. 5(a) is a cross-sectional view showing a pressure sensor having a conversion substrate according to another embodiment of the present invention, and FIG. 5(b) is a cross-sectional view showing a pressure sensor having a relay substrate according to still another embodiment of the present invention. [Figure 6]Figure 6(a) is a cross-sectional view showing a pressure sensor having a conversion substrate according to another embodiment of the present invention, and Figure 6(b) is a cross-sectional view showing a pressure sensor having a relay substrate according to yet another embodiment of the present invention. [Modes for carrying out the invention]

[0025] Embodiments of the present invention will be described in detail with reference to Figures 1 to 6. However, the present invention is not limited to the embodiments described herein.

[0026] The pressure sensor 100 according to an embodiment of the present invention is equipped with a means for dissipating heat from the conversion substrate 133 and a means for suppressing heat transfer to the conversion substrate 133, thereby effectively dissipating heat generated in the conversion substrate 133 to the external environment and suppressing heat transfer from the fluid to be pressure detected to the conversion substrate 133. Here, the means for dissipating heat from the conversion substrate is to indirectly bring the conversion substrate 133 (including heat-generating components) into thermal contact with the connector housing 131. Therefore, the case in which the conversion substrate 133 is indirectly brought into thermal contact with the connector housing 131 as the means for dissipating heat from the conversion substrate 133 will be described.

[0027] <Terminology> In this specification and the claims, “one end” and “the other end” of an element refer to the “lower end” and “upper end” in the drawings. Also, “upper end surface” and “lower end surface” refer to the surfaces located at the “upper end” and “lower end” in the drawings.

[0028] <Configuration of pressure sensor> A pressure sensor 100 according to an embodiment of the present invention will be described with reference to Figure 1.

[0029] The pressure sensor 100 consists of a fluid introduction unit 110, a pressure detection unit 120, a signal transmission unit (main body) 130, and a connecting member 140. The components of the pressure sensor 100 will be described in order below. The pressure sensor 100 is assembled by joining and fixing the fluid introduction unit 110 and the pressure detection unit 120, electrically connecting the pressure detection unit 120 and the signal transmission unit 130, and then integrally assembling the fluid introduction unit 110, the pressure detection unit 120, and the signal transmission unit 130 using the connecting member 140.

[0030] <Fluid introduction section> The fluid introduction section 110 introduces the pressure-detected fluid into the pressure chamber 112A, which will be described later, and comprises a metal joint member 111 and a metal base plate 112 connected to the other end of the joint member 111 by welding or the like.

[0031] The joint member 111 includes a female threaded portion 111a connected to a pipe (not shown) that introduces a fluid whose pressure is detected, and a port 111b that guides 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 base plate 112 by welding or the like. In this embodiment, the joint member 111 is provided with a female threaded portion 111a, but it is not limited to this, and for example, it may be provided with a male threaded portion, or a copper connecting pipe may be connected instead of the joint member 111.

[0032] The base plate 112 has a bowl shape that expands radially from one end to the other with respect to the central axis C of the pressure sensor 100, forming a pressure chamber 112A between it and the diaphragm 122, which will be described later.

[0033] <Pressure detection unit> The pressure detection unit 120 detects the fluid pressure in the pressure chamber 112A and comprises a detection unit housing 121 having a through hole, a diaphragm 122 that separates the pressure chamber 112A from the liquid-sealed chamber 124A described later, and a protective cover 123 positioned on the pressure chamber 112A side of the diaphragm 122. The pressure detection unit 120 also comprises a hermetic glass 124 sealed inside the through hole of the detection unit housing 121, a liquid-sealed chamber 124A filled with sealing oil between the recess on the pressure chamber 112A side of the hermetic glass 124 and the diaphragm 122, and a support column 125 positioned in the center of the hermetic glass 124. Furthermore, the pressure detection unit 120 includes a semiconductor sensor chip 126 supported by a support column 125 and positioned inside the liquid-sealed chamber 124A, a potential adjustment member 127 positioned around the liquid-sealed chamber 124A, a plurality of lead pins 128 fixed to the hermetic glass 124, and an oil-filling pipe 129 fixed to the hermetic glass 124.

[0034] The detection unit housing 121 is formed from a metallic material such as an Fe·Ni alloy or stainless steel to maintain strength around the hermetic glass 124. The diaphragm 122 and the protective cover 123 are both formed from metallic materials and are welded together at the outer peripheral edge of the through hole on the pressure chamber 112A side of the detection unit housing 121. The protective cover 123 is provided inside the pressure chamber 112A to protect the diaphragm 122 and has a plurality of communication holes 123a for the fluid introduced from the fluid introduction section 110 to pass through. After the pressure detection unit 120 is assembled, the detection unit housing 121 is welded from the outside to the outer peripheral edge of the base plate 112 of the fluid introduction section 110 by TIG welding, plasma welding, laser welding, etc.

[0035] The hermetic glass 124 is provided to protect the liquid-sealed chamber 124A, in which the semiconductor sensor chip 126 is liquid-sealed, from ambient environmental conditions such as moisture, dust, and heat in the air, to hold the multiple lead pins 128, and to insulate the multiple lead pins 128 from the detection unit housing 121. The semiconductor sensor chip 126 is supported on the liquid-sealed chamber 124A side of the support column 125 located in the center of the hermetic glass 124 by adhesive or the like. In this embodiment, the support column 125 is made of an Fe·Ni alloy, but is not limited to this. For example, it may be made of stainless steel or other metal materials, or it may be configured to be directly supported on the flat surface forming the recess of the hermetic glass 124 without a support column 125.

[0036] The semiconductor sensor chip 126 in this embodiment is a so-called one-chip type semiconductor sensor chip that includes an internal diaphragm made of a material having a piezoresistive effect (for example, single-crystal silicon), a bridge circuit formed by bridging multiple semiconductor strain gauges on the diaphragm, an amplification circuit that processes the output from the bridge circuit, and an integrated circuit such as an arithmetic processing circuit. The semiconductor sensor chip 126 is connected to multiple lead pins 128 by bonding wires 126a made of gold or aluminum, for example, and the multiple lead pins 128 constitute the external input / output terminals of the semiconductor sensor chip 126. Note that the semiconductor sensor chip 126 is not limited to this example and may also include configurations in which the bridge circuit section using strain gauges and the amplification circuit and arithmetic processing circuit sections are separated.

[0037] The potential adjustment member 127 is provided to place the semiconductor sensor chip 126 in an electric field-free (zero potential) environment and to prevent the circuits inside the chip from being adversely affected by the potential difference between the frame ground and the secondary power supply. The potential adjustment member 127 is positioned between the semiconductor sensor chip 126 and the diaphragm 122 in the liquid-sealed chamber 124A, is made of a conductive material such as metal, and is connected to a terminal of the semiconductor sensor chip 126 that is connected to zero potential.

[0038] Multiple lead pins 128 and an oil-filling pipe 129 are fixed to the hermetic glass 124 in a through-hole state by hermetic processing. In this embodiment, a total of eight lead pins 128 are provided. Specifically, three lead pins 128 are provided for external output (Vout), drive voltage supply (Vcc), and ground (GND), and five lead pins 128 are provided as terminals for adjusting the semiconductor sensor chip 126. Note that in Figure 1, four of the eight lead pins 128 are shown.

[0039] The oil filling pipe 129 is provided to fill the liquid-sealed chamber 124A with sealing oil (for example, silicone oil or a fluorine-based inert liquid). The other end of the oil filling pipe 129 is crushed and closed after the oil has been filled, as shown in Figure 1.

[0040] <Operation of the pressure detection unit> The operation of the pressure detection unit 120 will now be described. First, the diaphragm 122 is pressed by the fluid introduced into the pressure chamber 112A from the joint member 111. The pressure in the pressure chamber 112A applied to the diaphragm 122 is transmitted to the semiconductor sensor chip 126 via the sealing oil in the liquid sealing chamber 124A. This transmitted pressure deforms the silicon diaphragm of the semiconductor sensor chip 126, and a bridge circuit using a piezoresistive element converts the pressure into an electrical signal, which is then output from the integrated circuit of the semiconductor sensor chip 126 to the signal transmission unit 130 via bonding wires 126a and a plurality of lead pins 128.

[0041] <Signal transmission unit> The signal transmission unit (main body) 130 transmits the pressure signal detected by the pressure detection unit 120 to the outside, and includes an external connector housing 131 positioned adjacent to the other end of the pressure detection unit 120, and a flexible connector 132 with one end connected to a plurality of lead pins 128. The signal transmission unit 130 also includes a conversion board 133, which is a signal mediating board fixed to the connector housing 131 via three connection terminals that are signal connection means for exchanging signals with an external circuit, and the aforementioned connection terminals 134a to c, with one end connected through to the conversion board 133. An opening 133f is formed in the conversion board 133 to avoid interference with the oil filling pipe 129.

[0042] The connector housing 131 is made of an insulating resin or the like with relatively high thermal conductivity and includes a substrate housing portion 131a with a concave shape on one end, a connector connection portion 131b with a concave shape on the other end that is connected to an external connector (not shown), and a partition wall portion 131c positioned between the substrate housing portion 131a and the connector connection portion 131b. The internal space S defined by the substrate housing portion 131a contains a plurality of lead pins 128 extending from the hermetic glass 124, an oil filling pipe 129, a flexible connector 132, and a conversion board 133, etc.

[0043] The conversion board 133 includes a conversion circuit (not shown) that converts both the drive voltage and the pressure detection signal to accommodate the signal schemes of the drive voltage and the pressure detection signal. This conversion circuit includes a step-down circuit (not shown) that steps down the drive voltage (e.g., 8V to 36V) of a control circuit (not shown) connected to the outside of the pressure sensor 100 via connection terminals 134a to 134c to the drive voltage of the semiconductor sensor chip 126 (e.g., 5.0V), and a voltage shift circuit (not shown) that steps up the pressure detection signal of the pressure sensor 100 (e.g., 0.5V to 4.5V) to the pressure detection signal of the control circuit (e.g., 1V to 5V). In this way, by appropriately selecting the conversion board 133 installed inside the pressure sensor 100 according to the signal schemes of the drive voltage and the pressure detection signal, the difference between the drive voltage and the pressure detection signal can be absorbed without changing the design of the pressure detection unit 120, especially the semiconductor sensor chip 126, or the surrounding structure of the liquid-filled chamber 124A. By using a conversion board that performs input / output signal conversion processing in this manner, it is not necessary to stock semiconductor sensor chips corresponding to various input / output configurations, and the specifications of the conversion board can be modified accordingly. This allows for a production method that is suitable in terms of component procurement, manufacturing processes, and cost reduction. Furthermore, even if the input / output configuration of the pressure sensor does not match that of the control circuit, if the connected control circuit can perform input / output conversion processing, a circuit with input / output conversion functionality on the conversion board is unnecessary.

[0044] The connection terminals 134a to c are provided with at least three connections: one for external output (Vout), one for drive voltage supply (Vcc), and one for grounding (GND). To improve ease of assembly, for example, regarding connection terminal 134a, one end 134d of connection terminal 134a is inserted through a through hole provided in the conversion board 133, and the connection terminal 134a is connected to the conversion board 133 by soldering this through portion. A land portion 133n is formed at the connection portion of the conversion board 133, and it is electrically connected to the metal plate 135 by a conductive pattern. On the other hand, the other end of connection terminal 134a extends through the partition wall portion 131c to the connector connection portion 131b. The through portion of the partition wall portion 131c through which the connection terminals 134a to c pass is sealed with connection terminal fixing adhesive 134g.

[0045] <Connecting component> The connecting member 140 includes a crimping plate 141 that connects and fixes the fluid introduction section 110, the pressure detection section 120, and the signal transmission section 130 by crimping, and a butyl rubber seal 142 that is placed between the pressure detection section 120 and the signal transmission section 130. As shown in Figures 3 and 4, the butyl rubber seal 142 has a donut shape in plan view and a rectangular cross-section before being placed between the pressure detection section 120 and the signal transmission section 130.

[0046] The crimping plate 141 is formed in a cylindrical shape from a metal such as copper. The crimping plate 141 is positioned around the fluid introduction section 110, the pressure detection section 120, and the signal transmission section 130, and also houses the detection section housing 121 and the connector housing 131. It is fixed to the fluid introduction section 110 and the signal transmission section 130 by crimping. Through this crimping process, the butyl rubber seal 142, which is a sealing member, is sandwiched between the pressure detection section 120 and the signal transmission section 130 to perform waterproof and dustproof functions. A non-metallic insulating sheet 151 and insulating adhesive 152 may also be sandwiched between the butyl rubber seal 142 and the detection section housing 121, thereby improving the adhesion between the butyl rubber seal 142 and the metal surface of the detection section housing 121. Furthermore, the structure of the crimping section is not limited to the method described above. For example, as shown in Figure 11 of Patent Document 2, a fluid introduction section 110, which is integrally formed to accommodate the detection section housing 121 and the connector housing 131, may be crimped at the open end on the connector housing 131 side. In other words, any structure in which the butyl rubber seal 142 is sandwiched between the detection section housing 121 and the connector housing 131 and compressed and fixed by crimping or the like is acceptable.

[0047] <Seal structure using butyl rubber seals> Figure 2 is an enlarged cross-sectional view of the outside air seal section II in Figure 1. As shown in Figure 2, a butyl rubber seal 142, which has adhesive properties on both sides, is sandwiched between the upper end surface of the detection section housing 121 of the pressure detection section 120 and the lower end surface of the connector housing 131 of the signal transmission section 130, forming a seal structure. This allows for a seal structure to be formed using only the original components of the pressure detection section 120 and the signal transmission section 130, without, for example, providing a groove for an O-ring in the connector housing 131, thereby providing dustproof and waterproof performance. In this case, by making the crimping direction of the crimping plate 141 and the crushing direction of the butyl rubber seal 142 the same, the crimping load of the crimping plate 141 is applied to the butyl rubber seal 142. Furthermore, the outer diameter of the main body 130 is made larger than that of the pressure detection section 120 (forming a "roof"), and the outer diameter r2 of the butyl rubber seal 142 is made larger than that of the pressure detection section 120, causing it to protrude from the pressure detection section 120. This prevents water from accumulating on the mating surfaces of the adhesive joints between the pressure detection unit 120 and the signal transmission unit 130. Furthermore, by making the inner diameter of the main body 130 larger than the inner diameter r1 of the butyl rubber seal 142, that is, by making the radial width of the butyl rubber seal 142 wider than the wall thickness of the connector housing 131, the butyl rubber seal 142, which is sandwiched between the upper end surface of the detection unit housing 121 of the pressure detection unit 120 and the lower end surface of the connector housing 131 of the signal transmission unit 130 and compressed by the load from crimping, protrudes to the outside and inside of the space S. Because the butyl rubber seal 142 deforms in this way, the sealing area does not change even if the attachment position of the butyl rubber seal 142 is shifted, and the amount of compression and the compression load of the butyl rubber seal 142 can be stabilized.

[0048] The configuration of the upper end surface of the detection unit housing 121 of the pressure detection unit 120 and the lower end surface of the connector housing 131 of the signal transmission unit 130, as well as the configuration of the butyl rubber seal 142, improves the dustproof and waterproof performance between the pressure detection unit 120 and the signal transmission unit 130. Furthermore, since an O-ring is not used, for example, there is no need to provide a groove in the connector housing 131, the outer diameter of the pressure sensor can be made more compact, the pressure detection unit can be made common with existing parts, and thereby the manufacturing cost can be reduced. In addition, since the signal transmission unit 130 has a larger diameter than the pressure detection unit 120, condensation water does not accumulate on the bonding mating surface, improving the waterproofness of the bonding mating surface and preventing damage to the waterproofness of the bonding mating surface due to repeated volume expansion from freezing and thawing of accumulated condensation water. Furthermore, because the crimping plate 141 is attached from the signal transmission unit 130 side, which has a larger diameter than the pressure detection unit 120, the butyl rubber seal 142 is not scraped off at the edge of the crimping plate 141 when the crimping plate 141 is attached, nor does the butyl rubber seal 142 adhere to the crimping plate 141.

[0049] <Structure of butyl rubber seal> Figure 3 is a schematic diagram showing the shape of the butyl rubber seal 142 in plan view. Figure 4 is a schematic diagram showing the cross-sectional shape of the butyl rubber seal 142, where Figure 4(a) is an exploded perspective view showing the cross-sectional shape, and Figure 4(b) is a cross-sectional view showing the structure of the butyl rubber seal 142.

[0050] As shown in Figures 3 and 4(a), the butyl rubber seal 142 has a rectangular cross-section and a donut shape in plan view. Also, as shown in Figure 4(b), it has a three-layer structure consisting of a polypropylene / polyethylene nonwoven fabric sandwiched in the middle layer 142b, and the upper layer 142a and lower layer 142c made of butyl rubber adhesive. As a result, the butyl rubber seal 142 has double-sided adhesive properties. The butyl rubber seal 142 with a donut shape in plan view is formed, for example, by punching out a sheet-like material consisting of these three layers. The thickness t of the butyl rubber seal 142 may be, for example, 0.45 mm.

[0051] By adopting this three-layer structure, the upper layer 142a and lower layer 142c adhere to the lower end surface of the connector housing of the signal transmission unit 130 and the upper end surface of the detection unit housing 121 of the pressure detection unit 120, respectively, while the intermediate layer 142b prevents complete crushing and damage. Furthermore, when deformed by being sandwiched between the lower end surface of the connector housing 131 of the signal transmission unit 130 and the upper end surface of the detection unit housing 121 of the pressure detection unit 120, the upper layer 142a protrudes into the space S and the lower layer 142c protrudes out of the space S, providing a sealing structure with higher dustproof and waterproof performance.

[0052] <About insulating sheets> In a more desirable embodiment, a non-metallic insulating sheet 151 and insulating adhesive 152 are sandwiched between the butyl rubber seal 142 and the upper end surface of the detection unit housing 121. This improves the adhesion between the butyl rubber seal 142 and the metal surface of the detection unit housing 121, as described above. More specifically, the detection unit housing 121 is made of stainless steel, and a passive layer is formed on its surface. Therefore, in order to ensure a more reliable seal between the detection unit housing 121 and the butyl rubber seal 142, an insulating sheet (acrylic adhesive) 151 with an adhesive surface is bonded to the surface of the detection unit housing 121, and the gap is sealed with insulating adhesive 152. With this configuration, the butyl rubber seal 142 can adhere sufficiently to the upper end surface of the detection unit housing 121 via the insulating sheet 151, and the seal between the butyl rubber seal 142 and the detection unit housing 121 can be further improved.

[0053] Furthermore, in order to improve the sealing performance between the stainless steel detection unit housing 121 interface and the lower end of the connector housing 131 of the signal transmission unit 130, the outer diameter of the butyl rubber seal 142 is made larger than that of the insulating sheet 151, and a triple sealing structure is created using the adhesive properties of the butyl rubber seal 142, the insulating sheet 151, and the insulating adhesive 152.

[0054] <Means for heat dissipation of the conversion board> The conversion board 133 comprises an end face 133b on which various electronic components are mounted and which is separated from the connector housing 131, and an end face 133a on which connection terminals 134a~c etc. are soldered. In this embodiment, the heat-generating components 133h (e.g., transistors, regulators, etc.) are leaded and mounted on the other end face 133b. This conversion board 133 generates heat due to the transformation of the drive voltage, and if no countermeasures are taken, the electronic components on the conversion board may exceed their heat resistance temperature and be damaged. Therefore, in this embodiment, various heat dissipation means for the conversion board 133 are employed to prevent the electronic components on the conversion board 133 from exceeding their heat resistance temperature. This allows the heat generated in the conversion board 133 to be efficiently dissipated to the external environment, thereby improving the margin of safety regarding the heat resistance temperature of the conversion board 133. The heat dissipation means for the conversion board 133 in this embodiment will be described in detail below.

[0055] <Heat dissipation method for conversion board (lead-type heat-generating component)> As a means of heat dissipation for the conversion board 133, a lead-type heat-generating component 133h is used to form a heat dissipation path indicated by the dashed line (1) in Figure 1. The lead-type heat-generating component 133h is provided on the side facing the board 131a1. Since the area around this heat-generating component 133h is filled with a heat-conductive heat-dissipating adhesive 133g, an adhesive reservoir wall surface 131w is provided to define an adhesive reservoir region 131e between the connector housing 131 and the outer periphery of the connector housing 131 in order to prevent the heat-dissipating adhesive 133g from spreading onto the conversion board. In other words, in this embodiment, the adhesive reservoir region 131e is defined by the adhesive reservoir wall surface 131w and the board housing portion 131a and partition wall portion 131c of the main body 130. The lead-type heat-generating component 133h is housed in this adhesive reservoir region 131e, and a heat-conductive heat-dissipating adhesive 133g is filled only between the adhesive reservoir region 131e and the lead-type heat-generating component 133h. In this embodiment, the heat generated in the heat-generating component 133h is actively transferred to the heat-conductive heat-dissipating adhesive 133g surrounding the heat-generating component 133h, thereby enabling more efficient heat dissipation to the external environment via the connector housing 131. In this regard, it is desirable that the adhesive reservoir region 131e, which is surrounded by the adhesive reservoir wall surface 131w and the inner wall of the connector housing 131 in a plan view, be formed in a direction perpendicular to the insertion direction of the lead-type heat-generating component 133h (forward, backward, left, and right directions in the plan view of Figure 2(b)), as shown in Figure 2(b). This is because, compared to a shape that connects the intersection points of the adhesive reservoir wall 131w and the inner wall of the connector housing 131 by the shortest distance, or a shape that connects both ends of the adhesive reservoir wall 131w with a gentle curve (for example, an arc), the surface area of ​​the adhesive reservoir region 131e can be increased by making it rectangular in plan view, as in this embodiment. As a result, the amount of heat generated in the heat-generating component 133h that moves to the heat-dissipating adhesive 133g with thermal conductivity surrounding the heat-generating component 133h can be increased. In addition, as shown in Figure 2(b), the rectangular shape in plan view avoids the connection terminals 134b and 134c, allowing for effective use of space.Furthermore, since the leaded heat-generating component 133h is mounted on the conversion board 133 via leads 133l, the heat-generating portion of the heat-generating component 133h is physically separated from the conversion board 133, thereby preventing the electronic components of the conversion board 133 from exceeding their heat resistance temperature.

[0056] Here, the lead-type heat-generating component 133h is positioned on the outer diameter side of the connector housing 131 so that it is closer to the outside air. This makes it easier for the heat-dissipating adhesive 133g filling the area around the lead-type heat-generating component 133h to dissipate heat to the outside of the connector housing 131.

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

[0058] <Heat transfer suppression means> The pressure chamber 112A is into which the fluid to be pressure-detected is introduced. Depending on the fluid's operating conditions, very hot fluid (for example, around 130°C) may be introduced, becoming a heat source. In this case, heat from the pressure detection unit 120 (such as the heat from the hot fluid introduced into the pressure chamber 112A) could be transferred to the conversion substrate 133 (heat transfer from one end to the other, heat conduction, and heat radiation as shown in Figure 1), potentially canceling out the heat dissipation effect of the heat dissipation means (lead-type heat-generating component). Therefore, in this embodiment, various heat transfer suppression means are employed to prevent heat from the pressure detection unit 120 (such as the heat from the hot fluid introduced into the pressure chamber 112A) from being transferred to the conversion substrate 133. As a result, in this embodiment, heat transfer from the pressure detection unit 120 to the conversion substrate 133 can be suppressed, allowing the heat dissipation effect of the heat dissipation means (lead-type heat-generating component) to be fully realized. The means for suppressing heat transfer to the conversion substrate 133 in this embodiment will be described in detail below.

[0059] <First heat transfer suppression means to the conversion substrate (internal space)> An internal space S is used as a first means of suppressing heat transfer to the conversion substrate 133. Specifically, by providing the conversion substrate 133 near the other end of the substrate housing 131a, the distance L in the direction of the central axis C between the conversion substrate 133 and the detection unit housing 121 on the pressure detection unit 120 side in the internal space S can be set to be as large as possible. As a result, in this embodiment, heat from the pressure detection unit 120 side can be suppressed from being transferred to the conversion substrate 133 via the internal space S of air, which has a long heat transfer path and low thermal conductivity. However, the conversion substrate 133 and the other end of the substrate housing 131a are not in direct contact, as will be described in the next section.

[0060] <Second means for suppressing heat transfer to the conversion substrate (separation of the conversion substrate from the main body)> As shown in Figure 1, the conversion board 133 is positioned away from the other end and outer circumference of the board housing 131a so as not to come into direct contact with the connector housing 131. Instead of being directly supported by the connector housing 131, the conversion board 133 is supported at three points by three connection terminals 134a to 134c, as shown in Figures 4(a) and 4(b). These three connection terminals 134a to 134c are positioned towards the center of the conversion board 133, where a particular load is applied when the connection terminals 134a to 134c are soldered to the conversion board 133. Furthermore, as shown in Figure 1, the three connection terminals 134a to 134c are not in a straight line but have a stepped structure 134f, and the conversion board 133 can be supported at the stepped portion 134f. The position of this stepped portion 134f is set at a height that does not come into contact with the connector housing 131, so that when the conversion board 133 is housed in the connector housing 131, the conversion board 133 is supported at three points as described above. This structure allows the conversion board 133 to be positioned in a balanced manner, with minimal tilting relative to the connection terminals 134a-c even under soldering load. It also suppresses movement of the conversion board 133 towards the connector housing 131 (upward) and is firmly supported by the connection terminals 134a-c. Furthermore, as shown in Figure 1, the connection terminals 134a-c themselves are fixed to the connector housing 131 with connection terminal fixing adhesive 134g, and the lead-type heat-generating component 133h mounted on the conversion board 133 is fixed to the connector housing 131 with heat-dissipating adhesive 133g, thereby indirectly fixing the conversion board 133 to the connector housing 131. In this way, by positioning the conversion board 133 away from the other end of the board housing portion 131a so as not to directly contact the connector housing 131, 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 board 133.

[0061] In addition to the above, the conversion board 133 is provided such that its sides are separated from the outer circumference of the board housing 131a, thereby preventing stress from being applied from the connector housing 131 to the conversion board 133 due to the difference in thermal thermal expansion coefficients between the conversion board 133 and the connector housing 131. This prevents damage to the conversion board 133 caused by stress applied from the connector housing 131 to the conversion board 133 due to the difference in thermal expansion coefficients.

[0062] <Third means for suppressing heat transfer to the conversion substrate (flexible connector)> The aforementioned flexible connector 132 is used as a third means of suppressing heat transfer to the conversion substrate 133. Specifically, the flexible connector 132 is formed from, for example, a flexible printed circuit board (FPC), a thin conductive member, a single lead wire, or an assembly of lead wires, and connects a plurality of lead pins 128 and a metal plate 135 in a curved or bent state within the internal space S. Therefore, the connection distance between the plurality of lead pins 128 and the metal plate 135 can be set to be relatively large. In addition, the flexible connector 132 is thinner and has a smaller cross-sectional area than ordinary wiring material. As a result, in this embodiment, heat from the semiconductor sensor chip 126 side is transferred via the flexible connector 132, which has a long heat transfer path, and because of its small cross-sectional area, heat conduction to the conversion substrate 133 can be suppressed.

[0063] <Assembly process for the main unit> In the assembly process of the main body 130, first, the three connection terminals 134a to c are inserted into the main body 130. Then, as shown in Figure 1, connection terminal fixing adhesive 134g is applied (filled) around the connection terminals 134a to c so that the inserted connection terminals 134a to c 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 board 133. Next, as shown in Figure 1, heat dissipation adhesive 133g is filled into the adhesive reservoir area 131e of the main body 130. However, the filling of heat dissipation adhesive 133g is limited to about half to 80% of the fillable space volume of the adhesive reservoir area 131e, and is not filled to the limit of the fillable volume. Then, the conversion board 133 is inserted into the main body 130. At this time, the lead-type heat-generating component 133h is pre-assembled to the conversion board 133 and protrudes toward the board-facing surface 131a1, so it is inserted into the heat-dissipating adhesive 133g filled in the adhesive reservoir area 131e of the main body 130. Next, the main body 130 with the conversion board 133 inserted is placed in an oven and heated to cure the heat-dissipating adhesive 133g and the connector terminal fixing adhesive 134g. This heating also serves to dry the conversion board 133 to prevent migration due to moisture absorption of the conversion board 133. Then, the connector terminals 134a~c and the lead-type heat-generating component 133h are soldered to the conversion board 133. Finally, a solder inspection is performed to confirm that the soldering has been done properly. Note that if heat dissipation from the heat-generating component 133h via the heat-dissipating adhesive 133g is not performed, the step of filling the adhesive reservoir area 131e with heat-dissipating adhesive 133g is omitted. However, even in this case, a heat curing process is necessary, and 134g of the terminal fixing adhesive is heat-cured.

[0064] <Pressure sensor assembly process> Next, the assembly process of the pressure sensor 100 will be described. First, the pressure detection unit 120 and the signal transmission unit (main body) 130 are assembled as described above. Then, in the pressure detection unit 120, the sealing oil is filled into the liquid sealing chamber 124A via the oil filling pipe 129, and the oil filling pipe 129 is closed. Furthermore, the fluid introduction unit 110 is fixed to the pressure detection unit 120 by welding or the like. After that, the multiple lead pins 128 of the pressure detection unit 120 and the conversion board 133 of the signal transmission unit 130 are arranged in parallel so that they face upward, and one end of the flexible connector 132 and the other end are fixed to the multiple lead pins 128 and the surface of the metal plate 135 on the conversion board 133, respectively. Furthermore, the pressure detection unit 120 and the signal transmission unit 130 are positioned opposite each other on the same axis via a curved or bent flexible connector 132, and a butyl rubber seal 142 is sandwiched between the pressure detection unit 120 and the signal transmission unit 130. Finally, one end and the other end of the crimping plate 141 are engaged with the base plate 112 of the fluid introduction unit 110 and the connector housing 131 of the signal transmission unit 130, respectively, thereby integrally fixing the fluid introduction unit 110, the pressure detection unit 120, and the signal transmission unit 130. Alternatively, the aforementioned adhesive insulating sheet 151 may be interposed between the butyl rubber seal 142 and the pressure detection unit 120. In this case, during the assembly of the pressure detection unit 120, insulating adhesive 152 is applied to the upper surfaces of the detection unit housing 121, the hermetic glass 124, and the support column 125 of the pressure detection unit 120, and these upper surfaces are bonded to the insulating sheet 151.

[0065] In this case, if the pressure sensor 100 does not employ a curved or bent flexible connector 132, the assembly process of the pressure sensor 100 would require, for example, stacking from one end to the other in the direction of the central axis C. Therefore, the degree of freedom in the assembly process is extremely low, making it difficult to shorten the assembly time. However, in this embodiment, by connecting the pressure detection unit 120 and the signal transmission unit 130 via a curved or bent flexible connector 132, the degree of freedom in the assembly process of the pressure sensor 100 can be increased, thus shortening the assembly time. Furthermore, as mentioned above, if input / output signal conversion between the semiconductor sensor chip and the control circuit side is unnecessary and heat dissipation measures are unnecessary, it is also possible to omit the arrangement of the signal mediating substrate and directly electrically connect and fix the flexible connector and lead pins. This can be appropriately applied depending on the operating environment, required performance, productivity, etc.

[0066] <Other Embodiments> Unlike the aforementioned pressure sensor 100, which connects to the outside using a connector housing 131 having connection terminals 134a to c, the pressure sensor of this embodiment connects to the outside using lead wires that pass through the top cover and are directly or indirectly connected to a conversion board or relay board, which is a signal mediation board, for exchanging signals with the outside.

[0067] Figure 5(a) shows a pressure sensor 200 in which an external lead wire 21 is connected to a conversion board 233 via a connection terminal 213 to exchange signals between the pressure detection unit 120 and the outside, and Figure 5(b) shows a pressure sensor 300 in which an external lead wire 311 is connected to a relay board 333 via a connection terminal 313 to exchange signals between the pressure detection unit 120 and the outside. The same numbers are used for elements identical to those in the above embodiment, and their descriptions are omitted.

[0068] <Signal transmission unit according to another embodiment> In the embodiment shown in Figure 5(a), the signal transmission unit 230 transmits the pressure signal detected by the pressure detection unit 120 to the outside. It is positioned adjacent to the other end of the pressure detection unit 120 and includes a lead wire 211 for external connection and a flexible connector 132 with one end connected to a plurality of lead pins 128. The connection terminal 213 contacts one end of the core wire 212 of the lead wire 211 so as to be electrically connected at the other end, and is fixed to the lead wire 211 by soldering, ultrasonic welding, crimping, etc. Signal exchange with the external circuit takes place through the electrically connected and fixed lead wire 211 and connection terminal 213. The signal transmission unit 230 also includes a conversion board 233, which is a signal mediating board fixed to the upper cover 210 via the connection terminal 213, and a connection terminal 213 with one end connected through to the conversion board 233. The portion of the connection terminal 213, which is through-connected to the conversion board 233, that is inserted into the upper cover 210 is filled with terminal adhesive 213g to fill the gap. By sealing the gap in the portion through which the lead wire 211 inside the pressure sensor 200 passes with terminal adhesive 213g in this way, it is possible to prevent moisture from entering the inside of the upper cover 210 via the core wire 212 due to the breathing action of the upper cover 210. In this embodiment as well, the lower end of the upper cover 210 of the signal transmission unit 230 and the upper end of the detection unit housing 121 of the pressure detection unit 120 are sandwiched by a butyl rubber seal 142, or a butyl rubber seal 142, an insulating sheet 151, and insulating adhesive 152. In this case as well, the upper cover 210 is pressed so that the butyl rubber seal 142 protrudes outwards from the outer circumference of the detection unit housing 121. Furthermore, the upper cover 210 and the pressure detection unit 120, which constitute the signal transmission unit 230, are fixed by a waterproof case 215 that houses both the detection unit housing 121 and the upper cover 210, and a sealing material 216 that fills the gap between the waterproof case 215 and the upper cover 210. With this configuration, the sealing material 216 is filled so as to surround the butyl rubber seal 142 that protrudes from the detection unit housing 121.Therefore, the dustproof and waterproof properties of the mounting surfaces of the detection unit housing 121 and upper cover 210 can be further improved compared to when the butyl rubber seal, etc., is placed directly without being sandwiched by the adhesive properties of the butyl rubber seal 142, or further by the adhesive properties of the insulating sheet 151, insulating adhesive 152, etc. This is because, when the sealing material 216 seals around the protruding butyl rubber seal 142, the butyl rubber seal 142, which is made of rubber, generally has higher adhesion to the sealing material 216, which is made of resin, than the detection unit housing 121, which is made of metal, resulting in a tighter bond between the protruding butyl rubber seal 142 and the sealing material 216. An opening 233f is formed in the conversion board 233 to avoid interference with the oil filling pipe 129. Also, similar to the above embodiment, the flexible connector 132 is connected to the metal plate 135 mounted on the conversion board 233 by laser welding or the like. In this way, by connecting to the outside with lead wires 211, a pressure sensor 200 with a connection configuration different from that using connectors can be provided. Conventional connector types raise concerns about moisture intrusion from the top surface of the connector. However, as in this embodiment, by filling and sealing the entire external exit portion of the pressure sensor's lead wire with a sealing material, the waterproofness of the external exit portion of the lead wire can be improved.

[0069] The upper cover 210 is made of an insulating resin or the like with relatively high thermal conductivity and has a substrate housing portion 210a with a concave shape at one end. Multiple lead pins 128 extending from the hermetic glass 124, an oil filling pipe 129, a flexible connector 132, and a conversion board 233 are arranged in the internal space S defined by the substrate housing portion 210a. A heat-generating component 233h is mounted on the conversion board 233, similar to the embodiment described above, and the area around it is filled with a heat-dissipating adhesive 233g.

[0070] On the other hand, in the embodiment shown in Figure 5(b), the signal transmission unit 330 has the same configuration as the signal transmission unit 230, but the relay board 333 does not have a heat-generating component, and instead the board housing portion 310a above the relay board 333 has a space 333s. The relay board 333 is a signal mediating board that relays the drive voltage supplied from the external circuit via the lead wires 311 and connection terminals 313 and the pressure detection signal detected by the semiconductor sensor chip 126 to the external circuit, and relays the signal from the pressure detection unit 120. In this way, by assembling the pressure detection unit 120 and the signal transmission unit 330 separately and connecting and integrating them with the flexible connector 132, it is possible to improve workability and productivity by avoiding the difficult process of directly connecting the lead pins 128 and the core wires 312 of the lead wires 311 in a narrow space.

[0071] <Signal transmission unit according to further other embodiments> Figure 6(a) shows a pressure sensor 400 in which an external lead wire 411 is directly connected to a conversion board 433 to exchange signals between the pressure detection unit 120 and the outside, and Figure 6(b) shows a pressure sensor 500 in which an external lead wire 411 is directly connected to a relay board 533 to exchange signals between the pressure detection unit 120 and the outside. Elements identical to those in the previous embodiment are given the same numbers and their descriptions are omitted.

[0072] As shown in Figure 6(a), in this embodiment, the core wire 412 of the lead wire 411, which is a signal connection means, is directly connected to the conversion board 433, which is a signal mediation board. The other end 412d of the core wire 412 penetrates the conversion board 433, and the penetration portion of the core wire 412 is soldered to form a land portion 433n. In this way, by directly connecting the lead wire 411 to the conversion board 433, connection terminals are not required, and the number of parts can be reduced. In addition, the two connection processes, one between the conversion board and the connection terminal, and the other between the connection terminal and the lead wire, can be halved, thus shortening the manufacturing process. Furthermore, the portion of the lead wire 411 inserted into the upper cover 410 is filled with sealing adhesive 412g to fill the gap, preventing moisture from entering the inside of the upper cover via the core wire 412 due to the breathing action inside the upper cover 410.

[0073] The configuration of the embodiment shown in Figure 6(b) is the same as that of the embodiment shown in Figure 6(a). However, the signal mediating board in this embodiment is a relay board 533, and no heat-generating components are mounted on it. Instead, it relays the drive voltage supplied from the external circuit via the lead wires 511 and / or the pressure detection signal detected by the semiconductor sensor chip 126 to the external circuit. In this way, the pressure detection unit 120 and the signal transmission unit 530 are assembled separately and then connected and integrated with a flexible connector 132. This eliminates the need for difficult processes such as directly connecting the lead pins 128 and the core wires 512 of the lead wires 511 in a confined space, thereby improving work efficiency and productivity.

[0074] <Pressure sensor assembly process> Next, we will explain the assembly process for pressure sensors 200 to 500. Note that the process is the same as that for pressure sensor 100, as described above, and will be omitted from this explanation.

[0075] Multiple lead pins 128 of the pressure detection unit 120 and the signal mediating substrates (conversion boards or signal relay boards) of the signal transmission units 230-530 are arranged in parallel so that they face upward, and one end of the flexible connector 132 is joined to the surface of the multiple lead pins 128 and the metal plate 135 on the signal mediating substrate by laser welding. Furthermore, the pressure detection unit 120 and the signal transmission units 230-530 are arranged opposite each other on the same axis via the curved or bent flexible connector 132, and a butyl rubber seal 142 is sandwiched between the pressure detection unit 120 and the signal transmission units 230-530. Then, waterproof cases 215-515 are attached from the pressure detection unit 120 side, and sealing material 216-516 is filled between the periphery of the upper covers 210-510 and the waterproof cases 215-515, and the holding state is maintained until the sealing material hardens. As a result, the butyl rubber seal 142, which is a sealing member, is sandwiched between the upper end surface of the detection unit housing 121 of the pressure detection unit 120 and the lower end surfaces of the upper covers 210 to 510 of the signal transmission units 230 to 530, allowing it to deform sufficiently and maintain a state of high sealing performance. In addition, the flange portion inside the waterproof cases 215 to 515 and the base plate 112 are brought into close contact, preventing the sealing material 216 to 516 from leaking from below. In this way, the fluid introduction unit 110, the pressure detection unit 120, and the signal transmission units 230 to 530 are fixed together as a single unit.

[0076] With the above configuration, it is possible to provide a pressure sensor that can suppress an increase in the outer diameter of the pressure sensor in a configuration in which the conversion board is provided inside the pressure sensor. [Explanation of symbols]

[0077] 100 pressure sensors 110 Fluid introduction section 111 Joint Member 112 Base Plate 120 Pressure detection unit 121 Detection Unit Housing 122 Diaphragm 123 Protective Cover 124 Hermetic Glass 124A Liquid sealing chamber 125 Post 126 Semiconductor sensor chips 127 Potential Adjusting Member 128 lead pins 129 Oil filling pipe 130 Signal transmission unit (main body) 131 Connector Housing 131a Substrate housing section 131a1 Substrate opposing surface 131b Connector connection section 131c Bulkhead 131e Adhesive accumulation area 131w Adhesive buildup on wall surface 132 Flexible Wiring Material 133 Conversion board 133a One end face 133b Other end face 133f opening 133g heat dissipation adhesive 133h Heat-generating component 133L Lead 133n Land section 134a Connection terminal 134b Connection terminals 134c connector 134d One end 134e Other end 134f Step 135 Metal Plate 136 Circuit board rotation stopper 140 Connecting Members 141 Crimping Plate 142 Butyl rubber seal 142a upper layer 142b Middle class 142c lower layer 151 Insulating Sheet 152 Insulating Adhesive 210, 310, 410, 510 Top cover 210a, 310a, 410a, 510a Substrate housing section 211, 311, 411, 511 lead wires 212, 312, 412, 512 core wires 215,315,415,855 Waterproof Case 216, 316, 416, 516 sealing material 213 Connection terminals 213g Terminal Adhesive 233 Conversion board 233h Heat-generating component 233g heat dissipation adhesive 313 Connection terminals 313g Terminal Adhesive 333 Relay board 412g sealing adhesive 433 Conversion board 433h Heat-generating component 433g heat dissipation adhesive 512g sealing adhesive 533 Relay board C center axis L Distance between the conversion board and the housing in the direction of the central axis S interior space t Thickness of butyl rubber seal

Claims

1. A pressure detection unit having a pressure chamber, a semiconductor sensor chip for detecting the pressure of a fluid introduced into the pressure chamber, and a detection unit housing for housing the semiconductor sensor chip, Adjacent to the pressure detection unit is a signal transmission unit having a connection terminal and a connector housing, Equipped with, A pressure sensor characterized in that a sealing structure is formed by compressing a sealing member between the upper end surface of the detection unit housing and the lower end surface of the connector housing, the sealing member is sandwiched between the upper end surface region of the detection unit housing that is in contact with the sealing member and the lower end surface region of the connector housing that is in contact with the sealing member, and protrudes radially outward from the outer edge of the upper end surface region and radially inward from the inner edge of the lower end surface region, and has an area larger than the area of ​​the upper end surface region and the area of ​​the lower end surface region, respectively.

2. The pressure sensor according to claim 1, characterized in that the signal transmission unit further comprises a signal mediating board for connecting input and output signals with an external circuit.

3. The pressure sensor according to claim 2, characterized in that the signal mediating substrate is a conversion substrate that converts the drive voltage supplied to the semiconductor sensor chip from the external circuit and / or the pressure detection signal detected by the semiconductor sensor chip into an output corresponding to the external circuit.

4. The pressure sensor according to claim 2, characterized in that the signal mediating substrate is a relay substrate that relays the drive voltage supplied to the semiconductor sensor chip from the external circuit and / or the pressure detection signal detected by the semiconductor sensor chip to the external circuit.

5. The pressure sensor according to any one of claims 1 to 4, characterized in that the sealing member consists of three layers: an upper layer, an intermediate layer, and a lower layer, and the upper layer and the lower layer are adhesive, thereby providing double-sided adhesiveness.

6. The pressure sensor according to any one of claims 1 to 4, further comprising a crimping member that accommodates both the detection unit housing and the connector housing, wherein the end of the crimping member is crimped to compress and fix the pressure detection unit and the signal transmission unit, and compress the sealing member.

7. The pressure sensor according to claim 5, further comprising a crimping member that accommodates both the detection unit housing and the connector housing, wherein the end of the crimping member is crimped to compress and fix the pressure detection unit and the signal transmission unit, and compress the sealing member.

8. A pressure sensor according to any one of claims 1 to 4, characterized in that an adhesive insulating sheet is bonded to the upper end surface of the detection unit housing with an insulating adhesive, and the sealing member is in close contact with the upper end surface of the detection unit housing via the insulating sheet.

9. The pressure sensor according to claim 7, characterized in that an adhesive insulating sheet is bonded to the upper end surface of the detection unit housing with an insulating adhesive, and the sealing member is in close contact with the upper end surface of the detection unit housing via the insulating sheet.

10. The pressure sensor according to any one of claims 1 to 4, characterized in that the sealing member is made of butyl rubber.

11. The pressure sensor according to claim 9, characterized in that the sealing member is made of butyl rubber.

12. A pressure detection unit having a pressure chamber, a semiconductor sensor chip for detecting the pressure of a fluid introduced into the pressure chamber, and a detection unit housing for housing the semiconductor sensor chip, Adjacent to the pressure detection unit is a signal transmission unit having an upper cover, A waterproof case housing the pressure detection unit and the signal transmission unit, and a sealing material sealing the pressure detection unit and the signal transmission unit inside the waterproof case, Equipped with, A pressure sensor characterized in that a sealing structure is formed by compressing a sealing member between the upper end surface of the detection unit housing and the lower end surface of the upper cover, the sealing member is sandwiched between the upper end surface region of the detection unit housing that is in contact with the sealing member and the lower end surface region of the upper cover that is in contact with the sealing member, and protrudes radially outward from the outer edge of the upper end surface region and radially inward from the inner edge of the lower end surface region, and has an area larger than the area of ​​the upper end surface region and the area of ​​the lower end surface region, respectively.

13. The pressure sensor according to claim 12, characterized in that the signal transmission unit has a signal mediating board for connecting input and output signals with an external circuit inside the upper cover, and a board housing unit for housing the signal mediating board.

14. The pressure sensor according to claim 13, characterized in that the signal mediating substrate is a conversion substrate that converts the drive voltage supplied to the semiconductor sensor chip from the external circuit and / or the pressure detection signal detected by the semiconductor sensor chip into an output corresponding to the external circuit.

15. The pressure sensor according to claim 13, characterized in that the signal mediating substrate is a relay substrate that relays the drive voltage supplied to the semiconductor sensor chip from the external circuit and / or the pressure detection signal detected by the semiconductor sensor chip to the external circuit.

16. The pressure sensor according to any one of claims 12 to 15, characterized in that the sealing member consists of three layers: an upper layer, an intermediate layer, and a lower layer, and the upper layer and the lower layer are adhesive, thereby providing double-sided adhesiveness.

17. The pressure sensor according to any one of claims 12 to 15, characterized in that after filling the inside of the waterproof case with the sealing material, the detection unit housing and the upper cover are held together until the sealing material hardens, thereby maintaining the pressed state between the detection unit housing and the upper cover.

18. The pressure sensor according to claim 16, characterized in that after filling the inside of the waterproof case with the sealing material, the detection unit housing and the upper cover are held together until the sealing material hardens, thereby maintaining the pressed state between the detection unit housing and the upper cover.

19. A pressure sensor according to any one of claims 12 to 15, characterized in that an adhesive insulating sheet is bonded to the upper end surface of the detection unit housing with an insulating adhesive, and the sealing member is in close contact with the upper end surface of the detection unit housing via the insulating sheet.

20. The pressure sensor according to claim 18, characterized in that an adhesive insulating sheet is bonded to the upper end surface of the detection unit housing with an insulating adhesive, and the sealing member is in close contact with the upper end surface of the detection unit housing via the insulating sheet.

21. The pressure sensor according to any one of claims 12 to 15, characterized in that the sealing member is made of butyl rubber.

22. The pressure sensor according to claim 20, characterized in that the sealing member is made of butyl rubber.

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