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 stress 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 a relay board 50 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 relay board 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 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 a spacer 60 is installed so as to be interposed between the relay board which the sealant enters and the housing.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 object and send a 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 in such a way that it is liquid-tightly installed inside the case of the sensor unit so that it can be installed in a place exposed to the same environment as the measurement object. For example, when a structure is adopted in which a substrate that relays power supplies and electrical signals input and output to the sensor chip is interposed, by connecting conductive members such as lead wires and lead pins to the substrate, the process of installing inside 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. 8, 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 and connected to a sensor chip 11 to a relay substrate 50 respectively, it is housed in a case 20 and filled with a resin sealing material 26 to ensure liquid tightness that enables installation in various places.

[0006] Therefore, in this pressure sensor 1000, a sealing material 26 enters between the housing 12 and the relay substrate 50 and is joined and solidified in a state of being in close contact with both.

[0007] In such a structure, since each component material such as the relay substrate 50, 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 50 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 50 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 pulling out from the housing 12 will be applied.

[0008] Then, the lead pins 40 move in the length direction inside the housing 12, and cracks or the like continuous from the installation location side of the sensor chip 11 toward the relay substrate 50 may occur at the fixing locations of the lead pins 40 in the housing 12, resulting in a decrease in the liquid tightness 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 members fixed to the sensor fixing member.

Means for Solving the Problems

[0010] One aspect of the invention of a pressure sensor for solving the above problems is a pressure sensor in which a sensor for detecting the pressure of a measurement object 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 having a pressure chamber for receiving the pressure of the measurement object, 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. The sensor is conductively connected, and a member extended 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 and separates from the sensor fixing member, and the sealing material that enters between the sensor fixing member and the relay substrate is joined. A spacer is installed so as to be interposed between the relay substrate into which the sealing material enters and the sensor fixing member.

Advantages of the Invention

[0011] Thus, according to one aspect of the present invention, since the spacer is installed so as to be interposed between the relay substrate and the sensor fixing member, the volume of the sealing material that enters between the relay substrate and the sensor fixing member and joins to the pin member can be suppressed, and the joining volume of the sealing material that expands and contracts while joining to the pin member can be reduced.

[0012] Therefore, the stress (load) that relatively moves and displaces the pin member with respect to the sensor fixing member due to the expansion and contraction of the sealing material in response to temperature changes can be reduced, and the liquid tightness of the sensor fixing member to which the pin member is fixed can be ensured with high reliability.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

MODE FOR CARRYING OUT THE INVENTION

[0014] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIGS. 1 and 2 are diagrams for explaining a pressure sensor according to the first embodiment of the present invention.

[0015] <First Embodiment> In FIG. 1, a pressure sensor 100 is configured such that a pressure sensor unit 10 in which a pressure sensor chip (sensor) 11 is installed is attached to a refrigerant pipe in the unit for measuring the pressure of a refrigerant in, for example, a refrigeration cycle, and pressure information detected by the pressure sensor chip 11 is output 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 so as to be connectable by connecting a pressure sensor unit 10 having a resin waterproof case 20 formed in a substantially cylindrical shape to a pipe to be measured, through 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 annular metal cap 28 to which the joint member 30 is fixed is welded or the like and connected. This joint member 30 has a female thread 30s formed so as to be screwable to a pipe or the like whose pressure is to be measured. Through a port 30a communicating with the female 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 formed with a desired joint strength by welding the outer peripheral edge portions from the outside by TIG welding, plasma welding, laser welding, or the like.

[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 fix a member that penetrates 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 and isolates 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 in the installation space of the pressure sensor chip 11 formed by the hermetic glass 14 and the diaphragm 32 in 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 needless to say, 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, which are connected to each of the plurality of lead wires (external connection members) 38 from the external device A via a relay substrate 50 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 arranged 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 blocked after filling with the pressure transmission medium.

[0022] Here, the diaphragm 32 is prevented from being damaged by external forces or sudden pressures 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 so as to be freely flowable 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.

[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 plurality of 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 in which a sealing material 26 such as a urethane-based or epoxy-based resin is filled and sealed in a liquid-tight manner from the opening side opposite to the cap 28 of the waterproof case 20, thereby ensuring the liquid-tightness around the relay substrate 50 connecting the lead pins 40 and the lead wires 38. 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 50 by soldering, spot welding, etc. of the lead pins 40 and the core wire C of the lead wires 38, and then the relay substrate 50 together with the housing 12 is inserted into the waterproof case 20, and thereafter, the sealing material 26 is filled in the case 20 and sealed in a liquid-tight manner to perform the interior installation process. Note that the lead pins 40 in the figure are shown in white so as to be visible even at the locations hidden by the sealing material 26.

[0025] Here, the waterproof case 20 includes a small cylindrical portion 20a having a minimum diameter that forms a space filled with a sealing material 26 with a relay substrate 50 positioned 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 50 and the like inside, the waterproof case 20 positions the pressure sensor unit 10 and the waterproof case 20 by abutting the outer peripheral edge on the upper end surface side of the housing 12 against the step 20b between the small cylindrical portion 20a and the middle cylindrical portion 20c.

[0026] Furthermore, both ends of the lead pin 40 are embedded in a penetrating state on both sides of the hermetic glass 14 in 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 a 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) 50h of the relay substrate 50 and is soldered or the like to a land pattern (not shown) for conductive connection.

[0027] In addition, the multiple lead wires 38 that are drawn out so as to be connectable to the external device A are soldered to the relay board 50 with the bent core wires C as is with the 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 board 50 side. It goes without saying that the connection of the lead pins 40 and the lead wires 38 may be made not only by spot welding or molten metal such as solder S, but also by applying an adhesive containing a conductive material, and further, the connection may be made to the relay board 51 via a terminal member for connecting the core wires C, or a through hole 51h for connecting the core wires C is provided like the lead pins 40, and the core wires C is inserted through the through hole 51h for connecting the core wires C without bending the lead wires 38, and there is no need to limit the conductive connection means. The relay board 50 used here may be a rigid plate-like board as shown in FIG. 1, or a flexible so-called FPC (flexible printed circuit board). However, using a rigid plate instead of an FPC is advantageous in terms of ease of connection between the relay board 50, the lead pins 40, and the lead wires 38. For example, connecting the relay board 50 and the lead pins 40 and then connecting the lead wires 38 has the advantage that the work is easy since the lead wires are connected to a rigid board. Note that the relay board 50 may be equipped with a conversion adjustment circuit that converts input / output electrical characteristics for the pressure sensor unit 10, such as from voltage input to current output, stepping up / down input / output voltages, and A / D-D / A conversion.

[0028] As described in the interior fitting process above, 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 50 and penetrates between the relay board 50 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] And, between the relay substrate 50 to which the lead pins 40 are connected and the housing 12 (hermetic glass 14), a spacer 60 shown in FIG. 2 formed in an annular shape thinner than the housing 12 is installed on the upper surface 12t of the housing 12 so as to be interposed therebetween. The spacer 60 is formed such that the inner peripheral surface 60i coincides with the extended surface of the inner peripheral surface 12i of the housing 12, and the outer peripheral surface 60o is in proximity to and faces the inner peripheral surface 20ai of the small cylindrical portion 20a of the case 20. Further, the spacer 60 is set to a thickness T1 (<H) while the distance between the relay substrate 50 and the housing 12 is height H, and is manufactured so as to secure a space of the gap between the upper surface 60t of the spacer 60 and the lower surface 50u of the relay substrate 50 as an entry path R for the sealing material 26 that melts before solidification.

[0030] This spacer 60 is made of a material having a linear expansion coefficient 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 have a linear expansion coefficient of 4 to 18×10 -6 while the sealing material 26 is a synthetic resin of PU (polyurethane) or EP (epoxy) and has a linear expansion coefficient of 40 to 200×10 -6 in contrast, the spacer 60 is a synthetic resin of PBT (polybutylene terephthalate) or PPS (polyphenylene sulfide) and has 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 60 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.

[0031] With this structure, the sealing material 26 enters the space between the housing 12 from the entry path R between the relay substrate 50 and the spacer 60 and is filled around the lead pins 40. The filling capacity is reduced by the volume of the spacer 60 and it is joined to the lead pins 40. For this reason, the stress exerted on the relay substrate 50 and the housing 12 by the sealing material 26 that expands and contracts according to temperature changes can be reduced, and the pushing force and pulling force applied to the lead pins 40 fixed to the hermetic glass 14 of the housing 12 can be reduced, suppressing the occurrence of peeling and cracking in the hermetic glass 14, and preventing deterioration of the liquid tightness against leakage of the pressure transmission medium from the hermetic glass 14 side.

[0032] Thus, in the pressure sensor 100 of the present embodiment, the capacity of the sealing material 26 entering between the housing 12 and the relay substrate 50 can be reduced to reduce the load applied to the lead pins 40, and the amount of expansion and contraction of the sealing material 26 due to temperature changes can be reduced to suppress the stress for the lead pins 40 to move in the length direction with respect to the hermetic glass 14 of the housing 12.

[0033] Therefore, in this pressure sensor 100, it is possible to avoid the occurrence of peeling and cracking between the lead pins 40 and the hermetic glass 14, ensure liquid tightness, and improve reliability.

[0034] Here, in the present embodiment, since the case 20 is filled with the sealing material 26 to ensure liquid tightness around the relay substrate 50, it is possible to mold it in the sealing material 26 including the coated end of the lead wire 38, preventing the so-called breathing action in which moisture in the air enters through the core wire C due to temperature differences and pressure differences, etc., and also avoiding the occurrence of short circuits and migrations of the substrate circuit due to condensation of the relay substrate 50, etc.

[0035] <Second Embodiment> Next, FIGS. 3 and 4 are diagrams for explaining a pressure sensor according to a 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 only the characteristic portions will be described (the same applies to other embodiments described below).

[0036] In FIG. 3, the pressure sensor 200 includes a pressure sensor unit 10 similar to that of the above-described embodiment. In this embodiment, instead of the spacer 60 described above, a spacer 61 is made of a similar material and is installed on the upper surface 12t of the housing 12 so as to be interposed between the relay substrate 50 and the housing 12 (hermetic glass 14).

[0037] As shown in FIG. 4, 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, and a leg portion 61f is formed at the intersection of the large-diameter annular portion 61A and the connecting portion 61r.

[0038] In this spacer 61, a gap space is formed by separating the outermost peripheral surface 61Ao of the large-diameter annular portion 61A from the inner peripheral surface 20ai of the small cylindrical portion 20a of the case 20, and the innermost peripheral surface (wall surface) 61Bi of the small-diameter annular portion 61B is formed in a shape that secures a space while facing and approaching the outer peripheral surface 40o of the lead pins 40 arranged in a circular pattern.

[0039] And, in addition to the gap space in the radial direction between the annular portion 61A and the small cylindrical portion 20a of the waterproof case 20, the spacer 61 includes spaces between the leg portions 61f in contact with the upper surface 12t of the housing 12, between the annular portions 61A and 61B supported by the leg portions 61f, and between the lower surface 50u of the relay substrate 50 above and below these annular portions 61A and 61B and the upper surface 12t of the housing 12, which are ensured as the entry path R of the sealing material 26 that melts before solidification.

[0040] With this structure, the sealing material 26 enters from the entry path R of the gap space around the spacer 61 between the relay substrate 50 and the housing 12 and is filled around the lead pins 40, similar to the above-described embodiment. The filling capacity is reduced by the volume of the spacer 61 and it is joined to the lead pins 40.

[0041] Therefore, similar to the above-described embodiment, the spacer 61 can reduce the stress exerted on the relay substrate 50 and the housing 12 by the sealing material 26 that expands and contracts according to temperature changes. It can reduce the pushing force and pulling force applied to the lead pins 40 fixed to the hermetic glass 14 of the housing 12, suppress the occurrence of peeling and cracking, and prevent the deterioration of the liquid tightness against the leakage of the pressure transmission medium from the hermetic glass 14 side.

[0042] Furthermore, since the innermost peripheral surface (wall surface) 61Bi of the small-diameter annular portion 61B of the spacer 61 is in close proximity to the outer peripheral surface 40o of the lead pins 40 arranged in a circular pattern and narrows 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 made small. The bonding force of the sealing material 26 joined to the outer peripheral surface 40o of the lead pins 40 can be reduced (making it easier for peeling cracks etc. to occur), and the stress load that causes peeling and cracking in the hermetic glass 14 of the housing 12 can be suppressed.

[0043] Thus, in the pressure sensor 200 of the present embodiment, in addition to the operational effects according to the above-described embodiment, since the inner peripheral surface 61Bi of the annular portion 61B is in close proximity to the outer peripheral surface 40o of the lead pins 40, 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 can be more effectively suppressed, and the liquid tightness can be ensured with higher reliability.

[0044] <Third Embodiment> Next, FIGS. 5 and 6 are diagrams for explaining a pressure sensor according to the third embodiment of the present invention.

[0045] In FIG. 5, the pressure sensor 300 includes the pressure sensor unit 10 similar to that of the above-described embodiment. In this embodiment, instead of the spacer 61 described above, a spacer 63 is made of a similar material and is installed on the upper surface 12t of the housing 12 so as to be interposed between the relay substrate 50 and the housing 12 (hermetic glass 14).

[0046] As shown in FIG. 6, in addition to the annular portions 61A and 61B, the connecting portion 61r, and the leg portions 61f of the spacer 61 described above, the spacer 63 has a support portion 63s integrally formed at the upper part on the opposite side of the leg portion 61f. Similar to the leg portion 61f contacting the upper surface 12t of the housing 12 to support the annular portions 61A and 61B, the support portion 63s is made to contact and support the lower surface 50u of the relay substrate 50. Therefore, the spacer 63 can support the relay substrate 50 in a state of being placed thereon, particularly before the filling operation of the sealing material 26 and before the connection operation with the lead pins 40. Here, the support portion 63s of the spacer 63 secures an entry path R for the sealing material 26 that melts between the annular portions 61A and 61B supported by the leg portion 61f and the lower surface 50u of the relay substrate 50, in the same manner as securing the entry path R for the sealing material 26 that melts between the leg portion 61f and the upper surface 12t of the housing 12.

[0047] With this structure, the sealing material 26 enters from the entry path R of the gap space around the spacer 63 between the relay substrate 50 and the housing 12 and is filled around the lead pins 40, similar to the above-described embodiment. The filling capacity is reduced by the volume of the spacer 63 and is joined to the lead pins 40.

[0048] Therefore, the spacer 63, similar to the above-described embodiment, suppresses the occurrence of peeling and cracking due to the pushing force and pulling force of the lead pins 40, including reducing the volume of the sealing material 26 between the lead pins 40 by bringing the innermost peripheral surface (wall surface) 61Bi of the small-diameter annular portion 61B close to and facing the outer peripheral surface 40o of the lead pins 40 (narrowing the gap space), and can prevent the deterioration of the liquid tightness against the leakage of the pressure transmission medium from the hermetic glass 14 side.

[0049] Furthermore, during the filling operation of the sealing material 26 or the connection operation with the lead pins 40, the spacer 63 can facilitate various operations in a state where the relay substrate 50 is placed and supported on the support portion 63s, and the workability can be improved.

[0050] Thus, in the pressure sensor 300 of the present embodiment, in addition to the effects of the above-described embodiment, since the relay substrate 50 can be placed on the spacer 63 to perform various operations, various operations such as the conductive connection of the lead wires 38 and the lead pins 40 to the relay substrate 50 can be easily performed, and the work quality of the conductive connection and the like can be improved.

[0051] Here, as another aspect of the present embodiment, as shown in FIG. 7, instead of the annular portion 61B of the spacer 63 described above, a spacer 65 having a disk-shaped portion 65B may be provided. The disk-shaped portion 65B is formed with insertion holes 65h through which the lead pins 40 arranged in a circular shape and the oil filling pipes pass. The insertion holes 65h have an inner peripheral surface (wall surface) 65hi that is close to and faces the entire circumference of the outer peripheral surface 40o of the lead pins 40 that are connected and fixed to the relay substrate 50 and the hermetic glass 14 of the housing 12, narrowing the gap space, and securing an entry path R for the melting sealing material 26.

[0052] With this structure, the spacer 65 can reduce the volume of the sealing material 26 between the spacer 65 and the lead pins 40 compared to the annular portion 61B of the spacer 63 in the above-described embodiment, and further suppress the stress load that causes peeling and cracking in the hermetic glass 14 of the housing 12 by reducing the bonding force of the sealing material 26 that joins to the outer peripheral surface 40o of the lead pins 40 (making it easier to generate peeling cracks, etc.).

[0053] 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 may be defined by any desired combination of each of the specifically disclosed features.

Explanation of Reference Numerals

[0054] 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 50... Relay substrate 60, 61, 63, 65... Spacer 61A, 61B... Annular shape part 61Bi, 65i... Inner peripheral surface 61f... Leg part 63s... Support part 65B... Disk shape part 65h... Insertion hole 100, 200, 300... Pressure sensor A... External device C... Core wire PR... Pressure chamber R... Entry 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, 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 electrically connected to the sensor installed in the pressure chamber through a rod-shaped pin member that penetrates the sensor fixing member hermetically, and a member extending from an external device is electrically 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 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, A pressure sensor, characterized in that a spacer is provided so as to be interposed between the relay substrate into which the sealing material enters and the sensor fixing member.

2. The pressure sensor according to claim 1, wherein the spacer is made of a material having a linear expansion coefficient between that of the pin member and that of the sealing material.

3. The pressure sensor according to claim 1, wherein the spacer has a wall surface facing the outer peripheral surface of the pin member between the relay substrate and the sensor fixing member.

4. The pressure sensor according to claim 1, wherein the relay substrate is manufactured in a form in which it is placed on the spacer interposed between the sensor fixing member and performs an electrical connection operation with the pin member.

5. The pressure sensor according to claim 4, wherein the spacer is formed in a shape that secures a path space for the sealing material to enter between one or both of the relay substrate and the sensor fixing member.

Images