Pressure sensor

Abstract

The present invention provides a pressure sensor capable of ensuring liquid tightness with high reliability by reducing the magnitude of stress applied to a pin member fixed to a sensor fixing member. In a pressure sensor (100) in which a sensor chip (11) is connected to an FPC (relay substrate) (51) and is embedded in a case (20) in a liquid-tight manner by a sealing material (26), the sensor is provided in a housing (12) provided with a pressure chamber (PR), the FPC is conductively connected to the sensor chip via a lead pin (40) penetrating through the interior of the housing, and a lead (38) extending from an external device (A) is conductively connected to the FPC. And an FPC disposed between the sensor chip and the external device, the sealing material entering between the housing and the relay substrate being joined to the lead pins, the FPC being configured from a sheet-like material having flexibility.

Description

Technical Field

[0001] The present invention relates to a pressure sensor hermetically molded from a resin liquid. Background Art

[0002] Various sensors for detecting pressure, temperature, etc. are fixed near a measurement object and used in such a way as to send a detection signal to a measurement device or the like, and are often used in a form built in or externally attached to a measurement device.

[0003] Such various sensors are used by being hermetically built into a housing of a sensor unit in such a way that they can be set at a position exposed to the same environment as the measurement object. For example, when adopting a structure of a substrate that relays a power supply or an electrical signal input to and output from an opposed sensor chip, etc., by connecting a conduction component such as a lead or a lead pin to the substrate, the process of building it into the housing can be facilitated (see Patent Document 1).

[0004] Prior Art Documents

[0005] Patent Documents

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 2019-158726 Summary of the Invention

[0007] Technical Problem

[0008] However, in the pressure sensor described in Patent Document 1, for example, as Figure 7 shown, after a lead pin 40 fixed to a sealing glass 14 formed on the inner peripheral surface of a housing 12 and connected to a sensor chip 11 and a lead 38 connected to an external device A are respectively connected to a relay substrate 1050, they are housed in a housing 20 and filled with a resin sealing material 26 to ensure the liquid tightness that can be set at each position.

[0009] For this reason, in this pressure sensor 1000, there is a structure in which the sealing material 26 enters between the housing 12 and the relay substrate 1050 and is joined and cured in a state of being in close contact with both.

[0010] In this structure, since the constituent materials such as the relay substrate 1050, the housing 20, or the sealing material 26 each have a coefficient of linear expansion, the degree of expansion and contraction of each constituent material varies according to the temperature inside and outside the object to be measured. In particular, when the housing 12 (sealing glass 14) that fixes the lead pin 40 and the relay substrate 1050 are made of rigid bodies, and the difference in the amount of expansion and contraction between the sealing material 26 between the housing 12 and the relay substrate 1050 and the lead pin 40 is large, the lead pin 40 joined to the sealing material 26 is pushed into the housing 12 as the sealing material 26 expands and contracts, or is subjected to a stress in the direction of being pulled out from inside the housing 12.

[0011] As a result, the lead pin 40 moves in the longitudinal direction inside the housing 12, and thus there is a possibility that the liquid-tightness performance deteriorates due to cracks or the like that are continuous from the side where the sensor chip 11 is provided toward the relay substrate 1050 side at the position where the lead pin 40 is fixed in the housing 12.

[0012] Therefore, an object of the present invention is to provide a pressure sensor that can highly reliably ensure liquid-tightness by reducing the magnitude of the stress applied to the pin member fixed to the sensor fixing member.

[0013] Technical Solution

[0014] One aspect of the invention of the pressure sensor that solves the above problems is a pressure sensor, in which a sensor that detects the pressure of a measurement object is connected to a relay substrate and is hermetically built into a housing together with the relay substrate by a sealing material. The pressure sensor is characterized in that the sensor is provided in a sensor fixing member having a pressure chamber that receives the pressure of the measurement object, and the relay substrate is connected to the sensor provided in the pressure chamber through a rod-shaped pin member that hermetically penetrates the sensor fixing member, and at the same time, a member extending from an external device is conductively connected to the relay substrate, and the relay substrate is configured to be interposed between the sensor and the external device. The pin member protrudes from the sensor fixing member and is connected to the spaced-apart relay substrate, and is joined to the sealing material that enters between the sensor fixing member and the relay substrate. The relay substrate is made of a flexible sheet material.

[0015] Advantages of the Invention

[0016] Thus, according to one aspect of the present invention, since the relay substrate is made of a flexible sheet material, even if the sealing material that enters between the sensor fixing member and is joined to the pin member expands and contracts due to temperature changes, the relay substrate can be deformed due to its flexibility.

[0017] Therefore, it is possible to release the load stress that allows the pin member, which engages with the sealing material that expands and contracts due to temperature changes, to move relatively, and it is possible to ensure the liquid tightness of the sensor fixing member to which the pin member is fixed with high reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 FIG. is a longitudinal sectional view showing the schematic overall structure of the pressure sensor according to the first embodiment of the present invention.

[0019] Figure 2 FIG. is a longitudinal sectional view showing the schematic overall structure of the pressure sensor according to the second embodiment of the present invention.

[0020] Figure 3 FIG. is a longitudinal sectional view showing the schematic overall structure of the pressure sensor according to the third embodiment of the present invention.

[0021] Figure 4 FIG. is a longitudinal sectional view showing the schematic overall structure of the pressure sensor according to the fourth embodiment of the present invention.

[0022] Figure 5 FIG. is a perspective view showing the components of the main part thereof.

[0023] Figure 6 FIG. is a longitudinal sectional view showing the schematic overall structure of the pressure sensor according to the fifth embodiment of the present invention.

[0024] Figure 7 FIG. is a longitudinal sectional view showing the schematic overall structure of the prior art of the present embodiment.

[0025] REFERENCE SIGNS

[0026] 10: Pressure sensor unit, 11: Pressure sensor chip, 12: Housing, 14: Sealing glass, 20: Waterproof housing, 26: Sealing material, 38: Lead wire, 40: Lead wire pin, 51, 53, 55: FPC, 55c: Bending line, 61: Gasket, 100, 200, 300, 400, 500: Pressure sensor, A: External device, C: Core wire, E: Extension direction, F: Tilt direction, H: Horizontal direction, LR: Liquid seal chamber, PR: Pressure chamber, R: Entry path. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0027] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Figure 1 FIG. is a diagram for explaining the pressure sensor according to the first embodiment of the present invention.

[0028] <FIRST EMBODIMENT>

[0029] InFigure 1 In this case, the pressure sensor 100 is fabricated by, for example, mounting a pressure sensor unit 10 provided with a pressure sensor chip (sensor) 11 on a refrigerant pipe in the unit so as to measure the pressure of the refrigerant in the refrigeration cycle, and outputting the 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 configured to be connectable by connecting the pressure sensor unit 10 having a waterproof housing 20 made of resin formed in a substantially cylindrical shape to a pipe of a measurement object for guiding a fluid such as a gas or a liquid for detecting pressure, using a joint member 30 made of metal.

[0030] Here, the waterproof housing 20 is provided to cover the upper end face side of a cylindrical metal outer shell 12 having a wall thickness for housing the pressure sensor chip 11 of the pressure sensor unit 10, and the peripheral edge portion of a disk-shaped metal cap 28 to which the joint member 30 is fixed is welded and connected to the other end face side of the outer shell 12. The joint member 30 is formed with an internal thread 30s so as to be able to be screwed with a pipe for pressure measurement or the like, and enables the fluid supplied from the pipe in the direction of arrow P to be introduced into a pressure chamber PR which is a space surrounded by the cap 28, the outer shell 12, and a diaphragm 32 described later, via a port 30a communicating with the inside of the internal thread 30s. Among them, the outer shell 12 and the cap 28 are integrally formed with a desired joining strength by welding the outer peripheral edge portion from the outside by TIG welding, plasma welding, laser welding, or the like.

[0031] The outer shell (sensor fixing member) 12 is configured such that a support column 13 provided with the pressure sensor chip 11 on one end side is located at the center inside the inner cylinder, and a sealing glass 14 is formed which fills between the inner surface of the outer shell 12 and the outer surface of the support column 13 to ensure a closed state and liquid-tightly fixes a member penetrating therethrough inside.

[0032] In the pressure sensor unit 10, a metal diaphragm 32 is joined and fixed to the lower end face of the outer shell 12. The diaphragm 32 forms an airtight pressure chamber PR on the cap 28 side and isolates the setting space of the pressure sensor chip 11 on the support column 13 side inside the outer shell 12 from the pressure chamber PR.

[0033] Moreover, in the pressure sensor unit 10, a predetermined amount of silicone oil (or a fluorine-based inert liquid or the like) is filled as a pressure transmission medium, for example, in the setting space of the pressure sensor chip 11 formed by the sealing glass 14 and the diaphragm 32 inside the inner cylinder of the outer shell 12 to function as a liquid-sealed chamber LR.

[0034] Thus, the pressure sensor chip 11 functions as a pressure sensor, which detects the pressure of the fluid to be measured introduced into the pressure chamber PR from the pipe of the connection joint component 30 as the pressure change 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 configured to have a structure including the liquid seal chamber LR, and is manufactured to be a structure capable of detecting the fluid pressure of the measurement object introduced from the joint component 30 by the pressure sensor chip 11. In addition, as the pressure chamber, the fluid pressure of the measurement object can be directly applied to the sensor chip without a liquid seal chamber, and the measurement object is not limited to a liquid, and can also be various gases or a misty gas containing fine fluid particles, etc.

[0035] Here, the pressure sensor chip 11 is arranged to be supplied with power while being connected in conduction at multiple positions by making each of the multiple leads (external connection components) 38 from the external device A conductively connected to the lead pins (connection pin components) 40 connected via a relay substrate 51 to be described later via bonding wires 11w, and outputs a detection signal as pressure information. In addition, a pressure transmission medium is filled into the liquid seal chamber LR between the sealed glass 14 and the diaphragm 32 in the inner cylinder of the housing 12 via a filling oil pipe (not shown). These multiple lead pins 40 or the filling oil pipe are aligned at equal intervals around the support column 13 in the same circular shape, and are supported in insulation from the housing 12 via an insulator such as the sealed glass 14. In addition, one end of the above-mentioned filling oil pipe is closed after filling the pressure transmission medium.

[0036] Here, since the diaphragm protection cover 34 having multiple communication holes 34a is joined and fixed to the lower end surface of the housing 12, the diaphragm 32 is prevented from being damaged by external force or a sudden pressure in the pressure chamber PR in advance. In addition, a concave frame 16 is fixed to one end side of the sealed glass 14 and a lid-shaped shielding plate 17 is installed. The frame 16 accommodates the pressure transmission medium to flow freely between the pressure sensor chip 11 side and the diaphragm 32 side via the communication holes 17a formed in the shielding plate 17 to suppress sudden pressure changes.

[0037] In the present embodiment, the lead pins 40 are electrically connected to the pressure sensor chip 11 via bonding wires 11w by arranging 2 power supply terminals, 1 output signal terminal, and 5 adjustment terminals used during assembly. These multiple lead pins 40 protrude from one end face side of the housing 12 and are fixedly supported by the sealed glass 14 in a direction orthogonal to the top surface (installation surface) 12t of the housing 12. In addition, the number of these lead pins 40 is appropriately set according to the specifications of the pressure sensor chip 11.

[0038] On the upper end face side of the housing 12, a sealing material 26 such as a polyurethane-based or epoxy-based resin is filled in a liquid-tight manner from the opening side opposite to the cap 28 of the waterproof housing 20 for sealing. Thus, a pressure sensor unit 10 is constructed to ensure liquid tightness around the relay substrate 51 connecting the lead pins 40 and the lead 38. Here, the pressure sensor unit 10 is electrically connected to the relay substrate 51 by soldering, spot welding, etc. of the core wire C of the lead pin 40 or the lead 38. After being positioned and supported by the housing 12 (sealing glass 14), the relay substrate 51 and the housing 12 are inserted into the waterproof housing 20 together. Then, the inside of the housing 20 is filled with the sealing material 26 for liquid-tight sealing, thereby performing the built-in process. In addition, the lead pin 40 in the figure is shown hollow so as to be easily visible even at a position hidden by the sealing material 26.

[0039] Here, the waterproof housing 20 includes: a small cylindrical portion 20a with the smallest diameter that forms a space for filling the sealing material 26 on the opening side opposite to the cap 28 where the relay substrate 51 is located, 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 and having an inner diameter capable of accommodating the cap 28. In the built-in process of inserting the relay substrate 51 and the like inside, the waterproof housing 20 positions the pressure sensor unit 10 and the waterproof housing 20 by making the outer peripheral edge on the upper end face side of the housing 12 abut against the step 20b between the small cylindrical portion 20a and the middle cylindrical portion 20c.

[0040] Furthermore, in the lead pin 40, both end portions are buried in a penetrating state on both sides of the sealing glass 14 inside the inner cylinder of the housing 12. While the pressure sensor chip 11 is electrically connected to one end side on the liquid-sealed chamber LR side 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 the through holes 51h at multiple positions of the relay substrate 51 and is soldered to a pad pattern (not shown) etc. for electrical connection.

[0041] In addition, a plurality of lead wires 38 led out so as to be connectable to an external device A are conductively connected by directly soldering the bent core wires C to the relay substrate 51 using molten solder S, and a soldering pattern (not shown) for connecting the core wires C of the lead wires 38 is formed on the relay substrate 51 side. In addition, it goes without saying that in addition to molten metals such as spot welding or solder S, the connection of the lead pins 40 or the lead wires 38 can also be, for example, coating an adhesive containing a conductive material, etc. Further, it is also possible to connect to the relay substrate 51 via a terminal component for connecting the core wire C, or to provide a through hole 51h for connecting the core wire C like the lead pin 40 and insert the core wire C through it for connection, without bending the lead wire 38, and there is no need to particularly limit the means of conductive connection.

[0042] Here, as described in the above-built process, in order to support and fix the lead wire 38 in the extending direction and to fix the waterproof housing 20 to the outer housing 12, a sealing material 26 such as a polyurethane-based or epoxy-based resin filled into the waterproof housing 20 is made to flow around the relay substrate 51, enter the space between the outer housing 12 and solidify. Thus, the lead pin 40 of the present embodiment is hermetically sealed in the pressure sensor 100. In addition to being hermetically fixed and supported by closely bonding the sealing material 26 on the surface, the lead pin 40 is also hermetically held by the sealing glass 14 of the outer housing 12.

[0043] And, the relay substrate 51 connecting the lead pins 40, etc. is composed of an FPC (flexible printed circuit) 51 having soldering pads (not shown) formed on a flexible sheet. In addition, a conversion adjustment circuit for converting input / output electrical characteristics such as voltage input to current output, boosting and bucking of input / output voltages, A / D and D / A conversions, etc. can be installed on the FPC 51 for the pressure sensor unit 10. Since the FPC 51 has flexibility, even if some stress is applied from the connected lead pin 40 or the sealing material 26 filled into the waterproof housing 20, it will deform to release the stress.

[0044] With this structure, even if the sealing material 26 that enters the space between the outer housing 12 and engages with the lead pin 40 expands and contracts in response to temperature changes, the FPC 51 can deform due to its flexibility, and it is possible to avoid the lead pin 40 being applied as a thrust or a tensile force to the sealing glass 14 fixed to the outer housing 12. Therefore, the FPC 51 can suppress the relative movement of the lead pin 40 resulting in peeling and cracking of the sealing glass 14 of the outer housing 12, and can prevent deterioration of the liquid tightness against leakage of the pressure transmission medium from the sealing glass 14 side.

[0045] Thus, in the pressure sensor 100 of the present embodiment, the FPC 51 releases the expansion and contraction of the sealing material 26 that enters between the FPC 51 and the housing 12, thereby suppressing the stress that the lead pin 40 tends to move in the longitudinal direction relative to the sealing glass 14 of the housing 12.

[0046] Therefore, in the pressure sensor 100, peeling and cracking between the lead pin 40 and the sealing glass 14 can be avoided to ensure liquid tightness, and the reliability can be improved.

[0047] Here, in the present embodiment, since the sealing material 26 is filled in the housing 20 to ensure liquid tightness around the FPC 51, including the covered end of the lead 38, it can be molded into the sealing material 26, preventing the so-called breathing effect in which moisture in the air invades through the core wire C due to temperature difference or pressure difference, etc., thereby avoiding in advance short circuits or migrations of the substrate circuit due to dew condensation on the FPC 51 or the like.

[0048] <Second Embodiment>

[0049] Next, Figure 2 FIG. is a diagram for explaining the 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 reference numerals are given to the same components, and detailed description thereof is omitted, and the characteristic parts will be described (this also applies to other embodiments described below).

[0050] In Figure 2 the pressure sensor 200 includes the same pressure sensor unit 10 as in the above embodiment. In the present embodiment, instead of the above-described FPC 51, the FPC (relay substrate) 53 is made of the same sheet material.

[0051] The FPC 53 is in a uniform planar state as a whole (entire surface) and is conductively connected to each of the lead pins 40 passing through the through holes 53h at an inclination angle θ1 with respect to the horizontal direction H (horizontal plane) parallel to the top surface (installation surface) 12t of the housing 12. In other words, for example, when the connection operation is not performed on the lead pin 40 in a vertical posture (orthogonal) with respect to the top surface 12t of the housing, the FPC 53 is conductively connected in a posture in which the extension direction E (extension surface) of the FPC 53 is inclined with respect to the extension direction of the lead pin 40. Here, since the through holes 53h for soldering pads forming the FPC 53 are slightly inclined with respect to the lead pins 40, it is sufficient to maintain a circular shape without special measures, but it can also be formed into a long hole or an ellipse according to the inclination direction (this also applies to other embodiments).

[0052] With this structure, the FPC 53 can release stress from one or both of the lead pins 40 and the sealing material 26 by deforming due to the same flexibility. For example, when the lead pin 40 or the joint member 30 is in a vertically lead posture to fill the molten sealing material 26 in the waterproof housing 20, the air bubbles mixed in the molten sealing material 26 do not accumulate under the FPC 53 but float upward, thereby also avoiding deterioration of the liquid tightness around the FPC 53.

[0053] Thus, in the pressure sensor 200 of the present embodiment, the 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.

[0054] <Third Embodiment>

[0055] Next, Figure 3 is a diagram illustrating a pressure sensor according to a third embodiment of the present invention.

[0056] In Figure 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, the FPC (relay substrate) 55 is made of the same sheet material.

[0057] The FPC 55 is formed in a posture in which a part thereof is inclined at an angle θ2 with respect to the horizontal direction H (horizontal plane) parallel to the top surface 12t of the housing 12, and is conductively connected to each of the lead pins 40 passing through the through holes 53h. In other words, the FPC 55 is, for example, bent along a straight line near the center in the radial direction as a bending line (crease) 55c in the inclined direction F (inclined surface) with respect to the horizontal direction H, and is conductively connected to some of the lead pins 40 in an orthogonal posture while being conductively connected to some other lead pins 40 in an inclined posture.

[0058] Similar to the lead pins 40, the FPC 55 can be easily conductively connected in a state where the core wire C of the lead 38 passes through and protrudes from below by using the inclined space. In this case, as shown in the above-described embodiment, the conductive connection operation can be simply and easily performed without greatly bending the lead 38.

[0059] With this configuration, as in the above-described embodiment, the FPC 55 can deform due to its flexibility to release stress from one or both of the lead pins 40 and the sealing material 26, and at the same time, avoid deterioration of liquid tightness by reducing the accumulation of air bubbles mixed in the molten sealing material 26 under the FPC 55. In addition, the connection operation of the lead 38 can be facilitated by using the space on the lower side of the inclined surface. Further, for example, a structure can be adopted in which the core wire C is electrically connected to a pad portion of a wiring pattern (not shown) formed on the surface of the FPC 55 by soldering or the like, and then bent or curved (about 90°) upward in a direction parallel to the extending direction of the lead pin 40 at a position away from the electrical connection portion of each lead pin 40. That is, Figure 3 The inclination angle θ2 of Figure 3 is not limited to being an acute angle with respect to the horizontal direction (horizontal plane) H, and may also include an inclination up to a right angle position. With this configuration, the lead 38 can be assembled using the flexibility of the FPC 51 without bending.

[0060] Thus, in the pressure sensor 300 of the present embodiment, the effects of the above-described embodiment can be obtained, and in addition, the operation of connecting the lead 38 to the FPC 55 can be facilitated.

[0061] <Fourth Embodiment>

[0062] Next, Figure 4 and Figure 5 are diagrams for explaining the pressure sensor of the fourth embodiment of the present invention.

[0063] In Figure 4 , the pressure sensor 400 includes the same pressure sensor unit 10 as in the above-described embodiment. In the present embodiment, the pad 61 on which the FPC 51 is placed is provided on the top surface 12t of the housing 12.

[0064] As Figure 5 shown, the pad 61 is formed to be thinner than the housing 12 and has a shape in which circular ring-shaped portions 61A and 61B having different diameters are integrally connected by a connecting portion 61r. A leg portion 61f is formed at the lower portion of the intersection position of the large-diameter circular ring-shaped portion 61A and the connecting portion 61r, and a support portion 61s is formed at the upper portion of the intersection position.

[0065] With this structure, for the pad 61, the FPC 51 is supported by bringing the bottom surface 51u of the FPC 51 into contact with the top surface (loading surface) of the support portion 61s while the leg portion 61f is provided on the top surface 12t of the housing 12. In particular, various operations are performed in a state where the FPC 51 is placed before the filling operation of the sealing material 26 or before the connection operation with the lead pin 40.

[0066] In addition, the gasket 61 is formed such that a clearance space is formed by spacing the outermost peripheral surface 61Ao of the large-diameter annular-shaped portion 61A apart from the inner peripheral surface 20ai of the small cylindrical portion 20a of the housing 20, while bringing the innermost peripheral surface (wall surface) 61Bi of the small-diameter annular-shaped portion 61B close to and facing the outer peripheral surface 40o of the lead pins 40 arranged in a circular pattern, thereby ensuring the shape of the space. Therefore, in the gasket 61, in addition to the clearance space in the radial direction of the annular-shaped portion 61A or the small cylindrical portion 20a of the waterproof housing 20, clearance spaces are also ensured between the legs 61f in contact with the top surface 12t of the outer shell 12, or between the support portions 61s supporting the bottom surface 51u of the FPC 51, or between the annular-shaped portions 61A and 61B supported by the legs 61f, and between the bottom surface 51u of the FPC 51 above and below these annular-shaped portions 61A and 61B and the top surface 12t of the outer shell 12, serving as the entry path R for the molten sealing material 26 before curing.

[0067] The gasket 61 is made of a material having a coefficient of linear expansion between that of the lead pins 40 and the sealing material 26. For example, the lead pins 40 are made of a metal such as Fe, NiFe, or SUS, and the coefficient of linear expansion is 4 to 18×10 -6 -6, and the sealing material 26 is a synthetic resin of PU (polyurethane) or EP (epoxy), and the coefficient of linear expansion is 40 to 200×10 -6 -6, while the gasket 61 is a synthetic resin of PBT (polybutylene terephthalate) or PPS (polyphenylene sulfide), made of a material having a coefficient of linear expansion of 50 to 100×10 -6 -6, and the material is selected such that its coefficient of linear expansion is between that of the lead pins 40 and the sealing material 26. Therefore, the gasket 61 does not expand or contract more than the sealing material 26, and can reduce the influence of the volume change of the sealing material 26.

[0068] With this structure, the sealing material 26 enters from the entry path R in the clearance space around the gasket 61 between the FPC 51 and the outer shell 12 and fills around the lead pins 40, and the filling capacity is reduced by an amount corresponding to the volume of the gasket 61 and engages with the lead pins 40.

[0069] Therefore, the gasket 61 can reduce the stress applied by the sealing material 26 that expands and contracts in response to temperature changes to the FPC 51 and the outer shell 12, and can reduce the thrust or pull applied to the lead pins 40 fixed to the sealing glass 14 of the outer shell 12. Therefore, peeling and cracking of the sealing glass 14 due to the relative movement of the lead pins 40 can be suppressed, and deterioration of the liquid tightness against leakage of the pressure transmission medium from the sealing glass 14 side can be prevented.

[0070] Further, in the gasket 61, since the innermost peripheral surface (wall surface) 61Bi of the small-diameter circular ring-shaped portion 61B approaches and faces the outer peripheral surface 40o of the lead pins 40 arranged in a circular pattern, the clearance space is reduced. Therefore, the volume of the sealing material 26 between the circular ring-shaped portion 61B of the gasket 61 and the lead pins 40 can be reduced, and the stress load that causes peeling and cracking of the sealing glass 14 of the housing 12 can be suppressed by reducing the bonding force of the sealing material 26 that engages with the outer peripheral surface 40o of the lead pins 40 (by making it easier for peeling cracks, etc. to occur).

[0071] Further, the gasket 61 can facilitate various operations in a state where the FPC 51 is placed on the support portion 61s for support during the filling operation of the sealing material 26 or the connection operation with the lead pins 40, and can improve workability.

[0072] Thus, in the pressure sensor 400 of the present embodiment, in addition to achieving the effects of the above-described embodiment, the gasket 61 can reduce the filling amount of the sealing material 26 between the FPC 51 and the housing 12, and further suppress the stress that causes the lead pins 40 to move in the length direction with respect to the sealing glass 14 of the housing 12, and can ensure liquid tightness with higher reliability.

[0073] Further, in this pressure sensor 400, various operations such as placing the FPC 51 on the gasket 61 and making various operations such as the conductive connection between the lead 38 or the lead pins 40 and the FPC 51 easy can improve the work quality.

[0074] <Fifth Embodiment>

[0075] Next, Figure 6 is a diagram for explaining a pressure sensor according to a fifth embodiment of the present invention.

[0076] In Figure 6 the pressure sensor 500 includes the same pressure sensor unit 10 as in the above-described embodiment. In the present embodiment, the above-described FPC 55 is placed on the support portion 61s of the gasket 61.

[0077] With this configuration, by using the space between the inclined surface of the FPC 55 and the gasket 61, the lead 38 can be conductively connected to the FPC 55 through a simple and easy through-connection operation without significantly bending the lead 38.

[0078] Thus, in the pressure sensor 500 of the present embodiment, the effects of the above-described embodiment can be obtained.

[0079] The scope of the present invention is not limited to the illustrated and described exemplary embodiments, but also includes all embodiments that bring equivalent effects to those the present invention aims to achieve. Further, the scope of the present invention is not limited to the combinations of the features of the inventions specified by each claim, but may be defined by any desired combination of each of the disclosed specific features.

Claims

1. A pressure sensor, wherein: A sensor for detecting the pressure of a measurement object is connected to a relay substrate and is built into a housing together with the relay substrate in a liquid-tight manner through a sealing material. The pressure sensor is characterized in that: The sensor is installed in a sensor fixing member having a pressure chamber for receiving the pressure of the measurement object. The relay substrate is conductively connected to the sensor disposed in the pressure chamber via a rod-shaped pin member that passes through 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 configured to be interposed between the sensor and the external device. The pin member protrudes from the sensor fixing member to be connected to the spaced-apart relay substrate, and is engaged with the sealing material entering between the sensor fixing member and the relay substrate. The relay substrate is made of a flexible sheet material.

2. The pressure sensor according to claim 1, characterized in that: The relay substrate is deformed by stress applied from one or both of the pin member and the sealing material.

3. The pressure sensor according to claim 1, characterized in that: The relay substrate is composed of a flexible printed circuit board.

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

5. The pressure sensor according to claim 1, characterized in that: A part or the whole of the relay substrate is formed in a state inclined with respect to the extending direction of the pin member.

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

7. The pressure sensor according to claim 1, characterized in that: The relay substrate is manufactured in a form in which it is placed on a pad interposed between the sensor fixing member and the relay substrate so as to perform a conductive connection operation with the pin member.

8. The pressure sensor according to claim 7, characterized in that: The spacer is made of a material having a linear expansion coefficient between that of the pin member and that of the sealing material.

9. The pressure sensor according to claim 7, characterized in that: The pad has a mounting surface with a thickness parallel to the setting surface of the sensor fixing component, part or all of the relay substrate is made into a shape inclined relative to the extension direction of the pin component, and the core wire of the electric wire which is part of the component extending from the external device is conductively connected to the relay substrate.

10. The pressure sensor according to claim 7, characterized in that: The pad has a mounting surface with a thickness parallel to the setting surface of the sensor fixing component, a portion of the relay substrate is made to be parallel to the extension direction of the pin component, and the relay substrate is also parallel to the extension direction of the core wire of the electric wire which is part of the component extending from the external device and is conductively connected to the core wire.

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