Pressure sensor

Abstract

To provide a pressure sensor with which it is possible to secure liquid-tightness with high reliability by reducing the magnitude of stresses applied to a pin member which is secured to a sensor-fixing member.SOLUTION: Provided is a pressure sensor 100 in which a sensor chip 11 is connected to an FPC (relay board) 51 and liquid-tightly housed in a case 20 by a sealant 26. The sensor is installed in a housing 12 equipped with a pressure room PR, the FPC has the sensor chip conductively connected via a lead pin 40 penetrating the inside of the housing, and a lead wire 38 extending from an external apparatus A is conductively connected and arranged so as to be interposed between the sensor chip and the external apparatus. A sealant entering between the housing and the relay board is joined with the lead pin, and the FPC is composed of a flexible sheet-like material.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a pressure sensor that is liquid-tightly molded with resin.

Background Art

[0002] Various sensors for detecting pressure, temperature, etc. are used to be fixed near the measurement target and send the detection signal to a measuring device or the like, and are frequently used in a form built-in or externally attached to the measuring device.

[0003] This type of various sensors is used by being liquid-tightly installed in the case of the sensor unit so that it can be installed at a location exposed to the same environment as the measurement target. For example, when adopting a structure in which a substrate that relays a power supply and an electrical signal input to and output from the sensor chip is interposed, by connecting conductive members such as lead wires and lead pins to the substrate, the process of installing it in the case can be facilitated (see Patent Document 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the pressure sensor described in Patent Document 1, for example, as shown in FIG. 7, after connecting lead pins 40 that are fixed to a hermetic glass 14 formed on the inner peripheral surface of a housing 12 together with a lead wire 38 connected to an external device A to a relay substrate 1050 and then storing them in a case 20 and filling them with a resin sealing material 26, liquid tightness that can be installed everywhere is ensured.

[0006] Therefore, in this pressure sensor 1000, a sealing material 26 enters between the housing 12 and the relay substrate 1050 and is joined and solidified in a state of being in close contact with both of them.

[0007] In such a structure, since each component material such as the relay substrate 1050, the case 20, and the sealing material 26 has a coefficient of linear expansion, a difference will occur in the degree of expansion and contraction of each component material according to the temperature inside and outside including the measurement target. In particular, the housing 12 (hermetic glass 14) fixing the lead pins 40 and the relay substrate 1050 are composed of rigid bodies. When the amounts of expansion and contraction of the sealing material 26 and the lead pins 40 between the housing 12 and the relay substrate 1050 are greatly different, the lead pins 40 joined to the sealing material 26 will be pushed into the housing 12 as the sealing material 26 expands and contracts, or a stress in the direction of being pulled out from the housing 12 will be applied.

[0008] Then, the lead pins 40 move in the length direction inside the housing 12, and continuous cracks or the like may occur from the installation position side of the sensor chip 11 toward the relay substrate 1050 at the fixing position of the lead pins 40 in the housing 12, which may reduce the liquid-tight performance.

[0009] Therefore, an object of the present invention is to provide a pressure sensor capable of ensuring high reliability and liquid-tightness by reducing the magnitude of the stress applied to the pin member fixed to the sensor fixing member.

Means for Solving the Problems

[0010] One aspect of the invention of the pressure sensor for solving the above problems is a pressure sensor in which a sensor for detecting the pressure of a measurement target is connected to a relay substrate and is liquid-tightly installed in a case together with the relay substrate by a sealing material. The sensor is installed on a sensor fixing member including a pressure chamber for receiving the pressure of the measurement target, and the relay substrate is installed in the pressure chamber through a rod-shaped pin member that penetrates the sensor fixing member in a liquid-tight manner, and the sensor is conductively connected. A member extended from an external device is conductively connected to the relay substrate, and the relay substrate is arranged to be interposed between the sensor and the external device. The pin member protrudes from the sensor fixing member and is connected to the relay substrate spaced apart therefrom, and the sealing material entering between the sensor fixing member and the relay substrate is joined. The relay substrate is characterized by being composed of a flexible sheet-like material.

Effect of the Invention

[0011] Thus, according to one aspect of the present invention, since the relay substrate is composed of a flexible sheet-like material, the relay substrate can be deformed by its flexibility even when the sealing material that enters between the relay substrate and the sensor fixing member and joins the pin member expands and contracts due to temperature changes.

[0012] Therefore, it is possible to release the load stress that relatively moves the pin member to which the sealing material that expands and contracts due to temperature changes is joined, and it is possible to reliably ensure the liquid tightness of the sensor fixing member to which the pin member is fixed.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Mode for Carrying Out the Invention

[0014] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a diagram for explaining a pressure sensor according to a first embodiment of the present invention.

[0015] <First Embodiment> In FIG. 1, a pressure sensor 100 is configured to attach a pressure sensor unit 10 in which a pressure sensor chip (sensor) 11 is installed to a refrigerant pipe in the unit for measuring the pressure of a refrigerant in, for example, a refrigeration cycle, and output pressure information detected by the pressure sensor chip 11 to an external device A which is a control device for controlling the refrigeration cycle. The pressure sensor 100 of the present embodiment is constructed to be connectable by connecting a pressure sensor unit 10 provided with a resin waterproof case 20 formed in a substantially cylindrical shape to a pipe of a measurement object to which a fluid such as a gas or a liquid for detecting pressure is guided by a metal joint member 30.

[0016] Here, the waterproof case 20 is provided so as to cover the upper end face side of the thick cylindrical metal housing 12 that houses the pressure sensor chip 11 of the pressure sensor unit 10. On the other end face side of the housing 12, the peripheral edge of the disk-shaped metal cap 28 to which the joint member 30 is fixed is connected by welding or the like. This joint member 30 is formed with an internal thread 30s that can be screwed onto a pipe or the like to be measured for pressure. Through a port 30a that communicates with the internal thread 30s, the fluid supplied from the pipe in the direction of arrow P is introduced into the pressure chamber PR, which is a space surrounded by the cap 28, the housing 12, and a diaphragm 32 described later. Here, the housing 12 and the cap 28 are integrally welded from the outside by TIG welding, plasma welding, laser welding, etc. to achieve the desired joint strength.

[0017] The housing (sensor fixing member) 12 is arranged such that the support column 13 on which the pressure sensor chip 11 is installed on one end side is located at the center inside the inner cylinder. A hermetic glass 14 is formed to fixedly seal a member that penetrates through the inside while ensuring a closed state by filling the space between the inner surface of the housing 12 and the outer surface of the support column 13 in a liquid-tight manner.

[0018] In this pressure sensor unit 10, a metal diaphragm 32 is joined and fixed to the lower end face of the housing 12. The diaphragm 32 forms an airtight pressure chamber PR on the cap 28 side while isolating the installation space of the pressure sensor chip 11 on the support column 13 side inside the housing 12 from the pressure chamber PR.

[0019] And in this pressure sensor unit 10, a predetermined amount of silicone oil (or a fluorine-based inert liquid or the like) as a pressure transmission medium is filled into the installation space of the pressure sensor chip 11 formed by the hermetic glass 14 and the diaphragm 32 inside the inner cylinder of the housing 12 so as to function as a liquid seal chamber LR.

[0020] As a result, the pressure sensor chip 11 functions as a pressure sensor that detects the pressure of the fluid to be detected introduced into the pressure chamber PR from the pipe to which the joint member 30 is connected, as a pressure fluctuation of the pressure transmission medium in the liquid seal chamber LR via the diaphragm 32. That is, the pressure chamber PR of the present embodiment is constructed in a structure including the liquid seal chamber LR, and is fabricated in a structure that enables the pressure sensor chip 11 to detect the fluid pressure to be measured introduced from the joint member 30. Note that as the pressure chamber, it may be configured to directly load the fluid pressure to be measured on the sensor chip without including the liquid seal chamber, and it goes without saying that the object to be measured is not limited to a liquid, and may be a gas such as various gases or a mist-like gas containing fine fluid particles.

[0021] Here, the pressure sensor chip 11 is electrically connected at a plurality of locations via lead pins (connection pin members) 40 and bonding wires 11w that are connected to each of the plurality of lead wires (external connection members) 38 from the external device A via a relay substrate 51 to be described later, so as to be supplied with power and output a detection signal as pressure information. Further, the liquid seal chamber LR between the hermetic glass 14 and the diaphragm 32 in the inner cylinder of the housing 12 is filled with a pressure transmission medium via an oil filling pipe (not shown). These plurality of lead pins 40 and the oil filling pipe are aligned at equal intervals in a concentric circle around the support column 13, and are supported in insulation from the housing 12 via an insulator such as the hermetic glass 14. Note that one end of the above-described oil filling pipe is closed after filling with the pressure transmission medium.

[0022] Here, the diaphragm 32 is prevented from being damaged by external forces or sudden pressure in the pressure chamber PR by joining and fixing a diaphragm protection cover 34 having a plurality of communication holes 34a to the lower end surface of the housing 12. Further, a concave-shaped frame 16 is fixed to one end side of the hermetic glass 14, and a lid-shaped shield plate 17 is attached. The frame 16 accommodates a pressure transmission medium between the pressure sensor chip 11 side and the diaphragm 32 side through a communication hole 17a formed in the shield plate 17 to suppress sudden pressure fluctuations in a freely flowing manner.

[0023] In this embodiment, the lead pins 40 are arranged with 2 power supply terminals, 1 output signal terminal, and 5 adjustment terminals used during assembly, and are electrically connected to the pressure sensor chip 11 via bonding wires 11w. These multiple lead pins 40 protrude from one end surface side of the housing 12 and are fixedly supported by the hermetic glass 14 in a direction orthogonal to the upper surface (installation surface) 12t of the housing 12. Note that the number of these lead pins 40 is appropriately set according to the specifications of the pressure sensor chip 11.

[0024] On the upper end surface side of the housing 12, a pressure sensor unit 10 is constructed to ensure the liquid tightness around the relay substrate 51 that connects the lead pins 40 and the lead wire 38 by filling and sealing a sealing material 26 such as a urethane-based or epoxy-based resin in a liquid-tight manner from the opening side opposite to the cap 28 of the waterproof case 20. Here, the pressure sensor unit 10 is positioned and supported on the housing 12 (hermetic glass 14) by being conductively connected to the relay substrate 51 by soldering, spot welding, etc. of the lead pins 40 and the core wire C of the lead wire 38. Then, the relay substrate 51 together with the housing 12 is inserted into the waterproof case 20, and then the interior installation process is performed by filling the case 20 with the sealing material 26 and sealing it in a liquid-tight manner. Note that the lead pins 40 in the figure are shown in white for easy visibility even in the portions hidden by the sealing material 26.

[0025] Here, the waterproof case 20 includes a small cylindrical portion 20a with the minimum diameter that forms a space for filling the sealing material 26 where the relay substrate 51 is located on the opening side opposite to the cap 28, a middle cylindrical portion 20c adjacent to the small cylindrical portion 20a coaxially and having an inner diameter capable of accommodating the housing 12, and a large cylindrical portion 20e adjacent to the opposite side of the small cylindrical portion 20a coaxially with the middle cylindrical portion 20c and having an inner diameter capable of accommodating the cap 28. In the interior installation process of inserting the relay substrate 51 and the like inside, the outer peripheral edge on the upper end face side of the housing 12 is abutted against the step 20b between the small cylindrical portion 20a and the middle cylindrical portion 20c, so as to position the pressure sensor unit 10 and the waterproof case 20.

[0026] Furthermore, both ends of the lead pin 40 are embedded in a penetrating state on both sides of the hermetic glass 14 inside the inner cylinder of the housing 12. On one end side which is the liquid seal chamber LR side, the pressure sensor chip 11 is conductively connected via the bonding wire 11w. The other end side of the lead pin 40 corresponding to the power supply terminal and the output signal terminal penetrates through a plurality of through holes (via holes) 51h of the relay substrate 51 and is soldered or the like to a land pattern (not shown) for conductive connection.

[0027] Also, a plurality of lead wires 38 drawn out to be connectable to the external device A are soldered and conductively connected by directly melting the bent core wires C to the relay substrate 51 with solder S. A soldering pattern (not shown) for connecting the core wires C of the lead wires 38 is formed on the relay substrate 51 side. Needless to say, the connection of the lead pin 40 and the lead wire 38 may be not only by molten metal such as spot welding or solder S, but also by applying, for example, an adhesive containing a conductive material. Furthermore, it may be connected via a terminal member for connecting the core wire C to the relay substrate 51, or a through hole 51h for connecting the core wire C similar to the lead pin 40 may be provided, and the core wire C may be inserted and connected without bending the lead wire 38. There is no particular need to limit the means for conductive connection.

[0028] As described in the above interior fitting process, the lead pin 40 of this embodiment is supported and fixed in the extending direction of the lead wire 38 and fixed between the waterproof case 20 and the housing 12. The sealant 26, such as a urethane or epoxy resin, filled inside the waterproof case 20 flows around the relay board 51 and enters between the relay board 51 and the housing 12 and hardens, thereby sealing the lead pin 40 liquid-tightly inside the pressure sensor 100. In addition to the sealant 26 being tightly bonded to the surface of the lead pin 40 to fix and support the lead pin 40 liquid-tightly, the lead pin 40 is held by the hermetic glass 14 of the housing 12 while ensuring liquid-tightness.

[0029] The relay board 51 to which the lead pins 40 and the like are connected is composed of an FPC (flexible printed circuit) 51 in which soldering lands (not shown) are formed on a flexible sheet material. Note that this FPC 51 may be equipped with a conversion adjustment circuit that converts input / output electrical characteristics, such as voltage input to current output, input / output voltage boosting, input / output voltage drop, and A / D / D / A conversion, for the pressure sensor unit 10. Since this FPC 51 is flexible, it is designed to deform and release any stress applied from the lead pins 40 connected thereto or the sealing material 26 filled in the waterproof case 20.

[0030] With this structure, FPC 51 can deform due to its flexibility even if sealing material 26 that enters the space between FPC 51 and housing 12 and joins to lead pins 40 expands or contracts in response to temperature changes, and it is possible to prevent the lead pins 40 fixed to the hermetic glass 14 of the housing 12 from being subjected to stress due to a pushing force or a pulling force. Therefore, FPC 51 can suppress the lead pins 40 from moving relative to each other, causing peeling or cracking in the hermetic glass 14 of the housing 12, and can prevent deterioration of liquid-tightness against leakage of the pressure transmission medium from the hermetic glass 14 side.

[0031] Thus, in the pressure sensor 100 of the present embodiment, the FPC 51 can release the expansion and contraction of the sealing material 26 that enters between the FPC 51 and the housing 12, and suppress the stress that causes the lead pin 40 to move in the length direction with respect to the hermetic glass 14 of the housing 12.

[0032] Therefore, in this pressure sensor 100, it is possible to avoid the occurrence of peeling and cracking between the lead pin 40 and the hermetic glass 14, ensure the liquid tightness, and improve the reliability.

[0033] Here, in the present embodiment, since the sealing material 26 is filled in the case 20 to ensure the liquid tightness around the FPC 51, it is possible to mold it in the sealing material 26 including the coated end portion of the lead wire 38, and prevent the so-called breathing action in which moisture in the air enters through the core wire C due to temperature difference, pressure difference, etc., and avoid the occurrence of short circuits and migrations of the substrate circuit due to condensation of the FPC 51 or the like.

[0034] <Second Embodiment> Next, FIG. 2 is a diagram for explaining a pressure sensor according to the second embodiment of the present invention. Here, since this embodiment is configured substantially the same as the above-described embodiment, the same components are denoted by the same reference numerals and detailed description thereof is omitted, and the characteristic parts will be described (the same applies to other embodiments described below).

[0035] In FIG. 2, the pressure sensor 200 includes the same pressure sensor unit 10 as in the above-described embodiment. In the present embodiment, an FPC (intermediate substrate) 53 is manufactured from the same sheet material instead of the above-described FPC 51.

[0036] The FPC 53 is conductively connected to each of the lead pins 40 passed through the through-hole 53h in a posture with an inclination angle θ1 with respect to the horizontal direction H (horizontal plane) parallel to the upper surface (installation surface) 12t of the housing 12 while the whole (entire surface) remains in a uniform planar state. In other words, for example, when connection work is not performed on the lead pins 40 in a vertical posture (orthogonal) with respect to the housing upper surface 12t, the FPC 53 is conductively connected in a posture where the extension direction E (extension plane) of the FPC 53 is inclined with respect to the extension direction of the lead pins 40. Here, since the through-hole 53h in which the land for soldering the FPC 53 is formed has a slight inclination with respect to the lead pins 40, it is sufficient to remain circular without any particular countermeasures, but it may be formed into a long hole or an ellipse according to the inclination direction (the same applies to other embodiments).

[0037] With this structure, in addition to being able to relieve stress from one or both of the lead pins 40 and the sealing material 26 by deforming the FPC 53 with similar flexibility, for example, when the lead pins 40 and the joint member 30 are in a vertical posture and the sealing material 26 that melts in the waterproof case 20 is filled, it is possible to avoid the air bubbles mixed in the molten sealing material 26 from accumulating under the FPC 53 and floating upward to deteriorate the liquid tightness around the FPC 53.

[0038] Thus, in the pressure sensor 200 of the present embodiment, the operational effects of the above-described embodiment can be obtained, and in addition, the liquid tightness quality around the FPC 53 during production can be improved.

[0039] <Third Embodiment> Next, FIG. 3 is a diagram for explaining a pressure sensor according to the third embodiment of the present invention. In FIG. 3, the pressure sensor 300 includes the same pressure sensor unit 10 as in the above-described embodiment. In the present embodiment, instead of the above-described FPCs 51 and 53, an FPC (intermediate substrate) 55 is made of a similar sheet material.

[0040] The FPC 55 is manufactured so as to be in a posture with an inclination angle θ2 with respect to the horizontal direction H (horizontal plane) that is partially parallel to the upper surface 12t of the housing 12, and is conductively connected to each of the lead pins 40 passed through the through holes 53h. In other words, this FPC 55 is, for example, in a form that is bent in the inclination direction F (inclined plane) with respect to the horizontal direction H with a straight line crossing the radial direction near the center as a bending line (crease) 55c, and is conductively connected to some of the lead pins 40 in an orthogonal posture and to some other lead pins 40 in an inclined posture.

[0041] Similar to the lead pins 40, this FPC 55 can be easily conductively connected in a state where the core wire C of the lead wire 38 penetrates through and protrudes from the lower surface by utilizing the inclined space, and in this case, the work of conductively connecting without greatly bending the lead wire 38 as in the above-described embodiment can be performed simply and easily.

[0042] With this configuration, similar to the above-described embodiment, the FPC 55 can relieve stress from one or both of the lead pins 40 and the sealing material 26 by deforming due to flexibility, and can reduce the accumulation of air bubbles mixed into the molten sealing material 26 under the FPC 55 to avoid deterioration of liquid tightness. In addition, the connection work of the lead wire 38 can be facilitated by utilizing the space below the inclined plane. Further, for example, after conductively connecting the core wire C to the land portion of a wiring pattern (not shown) formed on the surface of the FPC 55 by soldering or the like, it may be structured to be bent or curved (approximately 90°) upward in a direction parallel to the extension direction of the lead pin 40 at a position deviated from the conductive connection portion of each lead pin 40. That is, the inclination angle θ2 in FIG. 3 may include not only an acute angle with respect to the horizontal direction (horizontal plane) H but also an inclination up to a right angle position. By adopting such a configuration, the lead wire 38 can be assembled without being bent by utilizing the flexibility of the FPC 51.

[0043] Thus, in the pressure sensor 300 of the present embodiment, the operational effects of the above-described embodiment can be obtained. In addition, the connection work of the lead wire 38 to the FPC 55 can be facilitated.

[0044] <Fourth Embodiment> Next, FIGS. 4 and 5 are diagrams for explaining a pressure sensor according to a fourth embodiment of the present invention. In FIG. 4, the pressure sensor 400 includes the same pressure sensor unit 10 as in the above-described embodiment. In the present embodiment, a spacer 61 for placing the above-described FPC 51 is installed on the upper surface 12t of the housing 12.

[0045] As shown in FIG. 5, the spacer 61 is formed in a shape in which annular portions 61A and 61B having different diameters and thinner than the housing 12 are connected by a connecting portion 61r so as to be integrated. A leg portion 61f is formed below the intersection of the large-diameter annular portion 61A and the connecting portion 61r, and a support portion 61s is formed above the intersection.

[0046] With this structure, the spacer 61 can be installed on the upper surface 12t of the housing 12 with the leg portion 61f, and the lower surface 51u of the FPC 51 can be brought into contact with and supported on the upper surface (placement surface) of the support portion 61s, so that various operations can be performed in a state where the FPC 51 is placed, particularly before the filling operation of the sealing material 26 and before the connection operation with the lead pin 40.

[0047] Further, in the spacer 61, a clearance space is formed by the outermost peripheral surface 61Ao of the large-diameter annular portion 61A being separated from the inner peripheral surface 20ai of the small cylindrical portion 20a of the case 20. The innermost peripheral surface (wall surface) 61Bi of the small-diameter annular portion 61B is formed in a shape that faces and secures a space while approaching the outer peripheral surface 40o of the lead pins 40 arranged in a circle. Therefore, in addition to the clearance space in the radial direction of the annular portion 61A and the small cylindrical portion 20a of the waterproof case 20, the spacer 61 includes the space between the legs 61f in contact with the upper surface 12t of the housing 12, the space between the support portions 61s that support the lower surface 51u of the FPC 51, the space between the annular portions 61A and 61B supported by the legs 61f, and the clearance space between the lower surface 51u of the FPC 51 above and below these annular portions 61A and 61B and the upper surface 12t of the housing 12, which is secured as the entry path R for the molten sealing material 26 before solidification.

[0048] This spacer 61 is made of a material with a linear expansion coefficient between that of the lead pins 40 and the sealing material 26. For example, if the lead pins 40 are made of a metal such as Fe, NiFe, or SUS and have a linear expansion coefficient of 4 to 18×10 -6 and the sealing material 26 is a synthetic resin of PU (polyurethane) or EP (epoxy) with a linear expansion coefficient of 40 to 200×10 -6 then the spacer 61 is made of a synthetic resin of PBT (polybutylene terephthalate) or PPS (polyphenylene sulfide) with a linear expansion coefficient of 50 to 100×10 -6 and is made by selecting a material such that its linear expansion coefficient is between that of the lead pins 40 and the sealing material 26. Therefore, the spacer 61 will not expand and contract more than the sealing material 26, and the influence of the volume change of the sealing material 26 can be reduced.

[0049] With this structure, the sealing material 26 enters from the entry path R of the clearance space around the spacer 61 between the FPC 51 and the housing 12 and is filled around the lead pins 40. The filling capacity is reduced by the volume of the spacer 61 and it is joined to the lead pins 40.

[0050] Therefore, the spacer 61 can reduce the stress exerted on the FPC 51 and the housing 12 by the sealing material 26 that expands and contracts in response to temperature changes, and can reduce the pushing force and pulling force applied to the lead pins 40 fixed to the hermetic glass 14 of the housing 12. From this, it is possible to suppress the occurrence of peeling and cracking in the hermetic glass 14 due to the relative movement of the lead pins 40, and it is possible to prevent the deterioration of the liquid tightness against the leakage of the pressure transmission medium from the hermetic glass 14 side.

[0051] Furthermore, in the spacer 61, since the innermost peripheral surface (wall surface) 61Bi of the small-diameter annular portion 61B is in close proximity to the outer peripheral surface 40o of the lead pins 40 arranged in a circular pattern, narrowing the gap space, the volume of the sealing material 26 between the annular portion 61B of the spacer 61 and the lead pins 40 can be reduced, and the bonding force of the sealing material 26 joined to the outer peripheral surface 40o of the lead pins 40 can be decreased (making it easier to generate peeling cracks, etc.), thereby suppressing the stress load that causes peeling and cracking in the hermetic glass 14 of the housing 12.

[0052] Furthermore, during the filling operation of the sealing material 26 or the connection operation with the lead pins 40, the spacer 61 can facilitate various operations in a state where the FPC 51 is placed and supported on the support portion 61s, thereby improving workability.

[0053] Thus, in the pressure sensor 400 of the present embodiment, in addition to the effects of the above-described embodiment, the spacer 61 can reduce the filling amount of the sealing material 26 between the FPC 51 and the housing 12, and can more effectively suppress the stress that causes the lead pins 40 to move in the length direction with respect to the hermetic glass 14 of the housing 12, ensuring higher reliability of the liquid tightness.

[0054] Furthermore, in this pressure sensor 400, the FPC 51 can be placed on the spacer 61 to perform various operations, facilitating various operations such as the electrical connection of the lead wires 38 and the lead pins 40 to the FPC 51, and improving the work quality.

[0055] <Fifth Embodiment> Next, FIG. 6 is a diagram for explaining a pressure sensor according to the fifth embodiment of the present invention. In FIG. 6, the pressure sensor 500 includes the same pressure sensor unit 10 as in the above-described embodiment. In this embodiment, the above-described FPC 55 is placed on the support portion 61s of the spacer 61.

[0056] With this configuration, by using the space between the inclined surface of the FPC 55 and the spacer 61, the lead wire 38 can be conductively connected to the FPC 55 by a simple and easy penetration connection operation that does not require the lead wire 38 to be greatly bent.

[0057] Thus, in the pressure sensor 500 of this embodiment, the operational effects of the above-described embodiment can be obtained.

[0058] The scope of the present invention is not limited to the illustrated and described exemplary embodiments, but also includes all embodiments that bring about equivalent effects to those intended by the present invention. Furthermore, the scope of the present invention is not limited to the combinations of the features of the invention specified by each claim, but can be defined by any desired combination of each of the disclosed specific features.

Description of Reference Numerals

[0059] 10... Pressure sensor unit 11... Pressure sensor chip 12... Housing 14... Hermetic glass 20... Waterproof case 26... Sealing material 38... Lead wire 40... Lead pin 51, 53, 55... FPC 55c... Bend line 61... Spacer 100, 200, 300, 400, 500... Pressure sensor A... External device C... Core wire E... Extension direction F... Inclination direction H... Horizontal direction LR... Liquid seal chamber PR... Pressure chamber R... Inlet path

Claims

1. A pressure sensor in which a sensor for detecting the pressure of a measurement target is connected to a relay substrate and is hermetically installed in a case together with the relay substrate by a sealing material, wherein the sensor is installed on a sensor fixing member having a pressure chamber for receiving the pressure of the measurement target, the relay substrate is conductively connected to the sensor installed in the pressure chamber through a rod-shaped pin member that penetrates the inside of the sensor fixing member in a liquid-tight manner, and a member extending from an external device is conductively connected to the relay substrate, and the relay substrate is arranged so as to be interposed between the sensor and the external device, the pin member is connected to the relay substrate that protrudes from and is separated from the sensor fixing member, and the sealing material that enters between the sensor fixing member and the relay substrate is joined, the relay substrate is characterized in that it is composed of a flexible sheet-like material.

2. The pressure sensor according to claim 1, wherein the relay substrate deforms according to stress applied from one or both of the pin member and the sealing material.

3. The pressure sensor according to claim 1, wherein the relay substrate is composed of a flexible printed circuit board.

4. The pressure sensor according to claim 1, wherein a part or the whole of the relay substrate is manufactured by being conductively connected to the pin member in a state inclined with respect to the horizontal direction during the conductive connection operation with the pin member.

5. The pressure sensor according to claim 1, wherein a part or the whole of the relay substrate is manufactured in a form inclined with respect to the extending direction of the pin member.

6. A part of the relay substrate is manufactured in a form parallel to the extending direction of the pin member and is also parallel to the extending direction of a member extending from the external device and is conductively connected to the member. The pressure sensor according to claim 1, characterized in that.

7. The pressure sensor according to claim 1, wherein the relay substrate is manufactured in a form that is placed on a spacer interposed between the relay substrate and the sensor fixing member and conducts connection work with the pin member.

8. The pressure sensor according to claim 7, wherein the spacer is composed of a material having a linear expansion coefficient between the pin member and the sealing material.

9. The spacer has a mounting surface with a thickness parallel to the installation surface on the sensor fixing member, and a part or the whole of the relay substrate is formed in a shape inclined with respect to the extending direction of the pin member, and a core wire of a wire which is a part of a member extending from an external device is conductively connected to the relay substrate. The pressure sensor according to claim 7, characterized in that.

10. The spacer has a mounting surface with a thickness parallel to the installation surface on the sensor fixing member, and a part of the relay substrate is formed in a form parallel to the extending direction of the pin member, and is also parallel to the extending direction of the core wire of a wire which is a part of a member extending from an external device and is conductively connected to the core wire. The pressure sensor according to claim 7, characterized in that.

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