Pressure sensor

Abstract

The present invention provides a pressure sensor which prevents a pin member fixed to a sensor fixing member from moving due to stress corresponding to the amount of expansion / contraction between a component and a sealing material, thereby ensuring liquid tightness. In a pressure sensor (100) in which a sensor chip (11) is connected to a relay substrate (50), which is disposed so as to be conductively connected to the sensor chip via a lead pin (40) passing through the inside of a housing (12), and which is housed in a liquid-tight manner by a sealing material (26), the sensor is provided in the housing (12) provided with a pressure chamber (PR), and the relay substrate (50) is disposed so as to be electrically connected to the sensor chip via the lead pin (40) passing through the inside of the housing. The relay substrate is electrically connected to a lead wire (38) extending from an external device (A) and interposed between the sensor chip and the external device, the lead wire pin is bonded to the sealing material entering between the housing and the relay substrate, and a restricting means for restricting the bonding force with the sealing material is disposed between the housing and the relay substrate.

Description

Technical Field

[0001] The present invention relates to a pressure sensor which is liquid-tightly molded by resin. Background Art

[0002] Various sensors for detecting pressure, temperature, etc. are fixed near a measurement object and are utilized in a manner of sending a detection signal to a measurement device or the like, and are widely used in a manner of being built in or external to the measurement device.

[0003] Such various sensors are utilized by being installed in a housing of a sensor unit in a liquid-tight manner so as to be installed in a location exposed to the same environment as the object to be measured. For example, in the case of a structure using a substrate that relays power and electrical signals input and output to and from the sensor chip, the installation process in the housing can be facilitated by connecting conductive components such as leads and lead pins to the substrate (see Patent Document 1).

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2019-158726 Summary of the invention

[0007] Problems to be solved by the invention

[0008] However, in the pressure sensor described in Patent Document 1, for example, Fig.10 As shown, after the lead 38 connected to the external device A and the lead pin 40 connected to the sensor chip 11 are respectively connected to the relay substrate 50, they are housed in the shell 20 and filled with a resin sealing material 26 to ensure liquid tightness that can be set in various places, wherein the lead pin 40 is fixed to the sealing glass 14 formed on the inner peripheral surface of the shell 12.

[0009] Therefore, in the pressure sensor 1000 , the sealing material 26 enters between the case 12 and the relay substrate 50 and is bonded and cured in a state of close contact with both.

[0010] In such a structure, since each component such as the relay substrate 50, the housing 20, and the sealing material 26 has its own linear expansion coefficient, the expansion / contraction degree of each component differs depending on the temperature of the inside and outside of the measurement object. In particular, when the housing 12 (sealing glass 14) and the relay substrate 50 that fix the lead pins 40 are made of a rigid body, and the expansion / contraction amount of the sealing material 26 and the lead pins 40 between the housing 12 and the relay substrate 50 is greatly different, the lead pins 40 bonded to the sealing material 26 are pressed into the housing 12 or are subjected to stress in the direction of being pulled out of the housing 12 in accordance with the expansion / contraction of the sealing material 26.

[0011] Then, lead pins 40 move in the longitudinal direction in case 12 , and cracks may occur in the fixed parts of case 12 with lead pins 40 , extending from the installation part side of sensor chip 11 toward relay substrate 50 , which may reduce the liquid-tightness.

[0012] Therefore, an object of the present invention is to provide a pressure sensor capable of ensuring liquid-tightness with high reliability by preventing a pin member fixed to a sensor fixing member from moving due to stress corresponding to the amount of expansion / contraction generated between a component and a sealing material.

[0013] Solutions to Solve Problems

[0014] One way of inventing a pressure sensor to solve the above-mentioned problem is a pressure sensor, which is a sensor for detecting the pressure of a measurement object, connected to a relay substrate, and liquid-tightly housed in a housing together with the relay substrate using a sealing material, characterized in that the sensor is arranged in a sensor fixing component, and the sensor fixing component has a pressure chamber that withstands the pressure of the measurement object, and the relay substrate is configured to be conductively connected to the sensor arranged in the pressure chamber via a rod-shaped pin component that liquid-tightly penetrates the sensor fixing component, and a component extending from an external device is conductively connected to the relay substrate, and the relay substrate is interposed between the sensor and the external device, the pin component protrudes from the sensor fixing component and is connected to the separated relay substrate, and is bonded to the sealing material that enters between the sensor fixing component and the relay substrate, and a limiting unit that suppresses the bonding force between the pin component and the sealing material is configured between the relay substrate and the sensor fixing component.

[0015] Effects of the Invention

[0016] Thus, according to one embodiment of the present invention, a limiting unit for suppressing the bonding force with the sealing material is arranged between the separated sensor fixing component and the relay substrate. Therefore, even if a large difference in expansion / contraction occurs between the sealing material and the pin component, the bonding force between the pin component and the sealing material to the extent of moving the pin component in the length direction can be maintained while maintaining the bonding portion.

[0017] Therefore, it is possible to provide a pressure sensor capable of preventing the pin member fixed to the sensor fixing member from relatively moving due to temperature change and ensuring liquid-tightness with high reliability. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0019] Figure 2 1 is a diagram showing a pressure sensor according to a second embodiment of the present invention, and is a longitudinal sectional view schematically showing its overall structure.

[0020] Figure 3 1 is a diagram showing a pressure sensor according to a third embodiment of the present invention, and is a longitudinal sectional view schematically showing its overall structure.

[0021] Figure 4 FIG. 1 is a diagram showing a pressure sensor according to a fourth embodiment of the present invention, and is a longitudinal sectional view schematically showing its overall structure.

[0022] Figure 5 It is a diagram showing another form of the fourth embodiment, and is a longitudinal sectional view showing a schematic overall structure thereof.

[0023] Figure 6 FIG. 1 is a diagram showing a pressure sensor according to a fifth embodiment of the present invention, and is a longitudinal sectional view schematically showing its overall structure.

[0024] Figure 7 1 is a diagram showing a pressure sensor according to a sixth embodiment of the present invention, and is a longitudinal sectional view schematically showing its overall structure.

[0025] Figure 8 It is a diagram showing a first other mode of the present embodiment and is a longitudinal sectional view showing a schematic overall structure thereof.

[0026] Fig. 9 It is a diagram showing a second alternative form of the present embodiment and is a longitudinal sectional view schematically showing the overall structure thereof.

[0027] Fig.10 It is a figure which shows the prior art of this embodiment, and is a longitudinal sectional view which shows the schematic whole structure. DETAILED DESCRIPTION

[0028] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Figure 1 It is a diagram for explaining the pressure sensor according to the first embodiment of the present invention.

[0029] <First Embodiment>

[0030] exist Figure 1 In the embodiment, the pressure sensor 100 is manufactured as follows: a pressure sensor unit 10 provided with a pressure sensor chip (sensor) 11 is installed in a refrigerant piping in the unit, for example, to measure the pressure of the refrigerant in a refrigeration cycle, and the pressure information detected by the pressure sensor chip 11 is output to a control device that controls the refrigeration cycle, that is, an external device A. The pressure sensor 100 of this embodiment is configured to be connectable by connecting the pressure sensor unit 10 having a resin waterproof housing 20 formed in a substantially cylindrical shape to a piping that guides a fluid such as a gas or liquid to be measured, for example, using a metal joint member 30.

[0031] The waterproof housing 20 is provided to cover the upper end surface side of a thick cylindrical metal housing 12 that accommodates the sensor chip 11 of the pressure sensor unit 10, and the peripheral edge of a disc-shaped metal cover 28 that fixes the joint component 30 is connected by welding or the like to the other end surface side of the housing 12. The joint component 30 is formed with an internal thread 30s in a manner that allows it to be threadedly fixed to a pipe or the like of a pressure measurement object, and a fluid supplied from the pipe in the direction of arrow P is introduced into a pressure chamber PR, which is a space surrounded by the cover 28, the housing 12, and the diaphragm 32 described later, through a port 30a connected to the internal thread 30s. The outer peripheral edges of the housing 12 and the cover 28 are welded from the outside by TIG welding, plasma welding, laser welding, etc., and are integrated with a desired bonding strength.

[0032] The housing (sensor fixing component) 12 is configured so that a pillar 13 with a pressure sensor chip 11 on one end is located at the center of the inner tube, and a sealing glass 14 is formed to be filled between the inner surface of the housing 12 and the outer surface of the pillar 13 to ensure a closed state and to fix the components passing through the interior in a liquid-tight manner.

[0033] In the pressure sensor unit 10, a metal diaphragm 32 is fixedly bonded to the lower end surface of the housing 12. The diaphragm 32 forms an airtight pressure chamber PR on the cover 28 side and isolates the installation space of the pressure sensor chip 11 on the support 13 side in the housing 12 from the pressure chamber PR.

[0034] Furthermore, in the pressure sensor unit 10, the installation space of the pressure sensor chip 11 formed by the sealing glass 14 and the diaphragm 32 in the inner cylinder of the housing 12 is filled with a predetermined amount of silicone oil (or fluorine-based inert liquid, etc.) as a pressure transmission medium to act as a liquid seal chamber LR.

[0035] Thus, the pressure sensor chip 11 functions as a pressure sensor that detects the pressure of the fluid of the detection object introduced into the pressure chamber PR from the piping connected to the joint member 30 via the diaphragm 32 as the pressure change of the pressure transmission medium in the liquid seal chamber LR. That is, the pressure chamber PR of the present embodiment is configured to have a structure including the liquid seal chamber LR, and is made into a structure capable of detecting the pressure of the fluid of the measurement object introduced from the joint member 30 by the pressure sensor chip 11. In addition, as the pressure chamber, it is also possible to not have a liquid seal chamber, and directly load the pressure of the fluid of the measurement object on the sensor chip for measurement. In addition, the measurement object is not limited to liquids, and of course it can also be a gas such as various gases, or a mist gas containing tiny fluid particles.

[0036] Here, the pressure sensor chip 11 is configured to supply power to a plurality of leads (external connection components) 38 from an external device A respectively, and output a detection signal as pressure information by connecting the lead pins (connection pin components) 40 connected to the relay substrate 50 described later via bonding wires 11w at a plurality of locations. In addition, the pressure transmission medium is connected to the lead pins (connection pin components) 40 connected to the relay substrate 50 described later via bonding wires 11w. Figure 8 The oil filling tube (shown as 89 in the figure) is filled in the liquid seal chamber LR between the sealing glass 14 and the diaphragm 32 in the inner cylinder of the housing 12. These multiple lead pins 40 and the oil filling tube are arranged in the same circle at equal intervals with the support 13 as the center, and are supported to be insulated from the housing 12 via insulating materials such as the sealing glass 14. In addition, the oil filling tube is closed at one end after being filled with the pressure transmission medium.

[0037] The diaphragm 32 is prevented from being damaged by external force 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. In addition, a concave frame 16 is fixed to one end of the sealing glass 14 and a cover-shaped shielding plate 17 is installed. The frame 16 accommodates the pressure transmission medium so that it can flow freely between the pressure sensor chip 11 side and the diaphragm 32 side through the communication holes 17a formed in the shielding plate 17 to suppress sudden pressure changes.

[0038] In this embodiment, the lead pins 40 are arranged with two power supply terminals, one output signal terminal, and five adjustment terminals used during assembly, and are electrically connected to the pressure sensor chip 11 via bonding wires 11w, and these multiple lead pins 40 are fixedly supported on the sealing glass 14 in a manner protruding from one end surface side 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.

[0039] The sealing material 26 such as polyurethane or epoxy resin is filled and sealed on the upper end surface side of the housing 12 in a liquid-tight manner from the opening side opposite to the cover 28 of the waterproof housing 20, thereby constituting the pressure sensor unit 10 that ensures liquid-tightness around the relay substrate 50 connected to the lead pins 40 and the leads 38. Among them, after the pressure sensor unit 10 is conductively connected to the relay substrate 50 by soldering, spot welding, etc. of the core wires C of the lead pins 40 and the leads 38 and positioned and supported on the housing 12 (sealing glass 14), the relay substrate 50 is inserted into the waterproof housing 20 together with the housing 12, and then the sealing material 26 is filled in the housing 20 to seal it in a liquid-tight manner, thereby performing the interior installation process.

[0040] The waterproof case 20 includes: a small cylindrical portion 20a having the smallest diameter, which is located at the opening side of the cover 28 opposite to the relay substrate 50 and forms a space filled with the sealing material 26; a middle cylindrical portion 20c, which is coaxially adjacent to the small cylindrical portion 20a and has an inner diameter capable of accommodating the housing 12; and a large cylindrical portion 20e, which is coaxially adjacent to the middle cylindrical portion 20c on the opposite side of the small cylindrical portion 20a and has an inner diameter capable of accommodating the cover 28. In the interior installation process of inserting the relay substrate 50 and the like into the waterproof case 20, the outer peripheral edge of the upper end surface side of the housing 12 is brought into contact with the step 20b between the small cylindrical portion 20a and the middle cylindrical portion 20c, thereby positioning the pressure sensor unit 10 and the waterproof case 20.

[0041] Furthermore, both end portions of the lead pins 40 are buried in a through-state on both sides of the sealing glass 14 in the inner tube of the housing 12, and are conductively connected to the pressure sensor chip 11 via bonding wires 11w on the liquid seal chamber LR side, i.e., one end side, and the other end side of the lead pins 40, which are equivalent to power supply terminals and output signal terminals, penetrates through holes (through holes) 50h at multiple locations of the relay substrate 50 and is conductively connected to a pad pattern not shown in the figure by soldering or the like.

[0042] In addition, the plurality of leads 38 that are led out in a manner that allows connection to an external device A are directly connected to the relay substrate 50 by soldering the bent core wire C with molten solder S, and a soldering pattern (not shown) for connecting the core wire C of the leads 38 is formed on the relay substrate 50 side. In addition, the connection between the lead pins 40 and the leads 38 can be applied not only by spot welding, solder S or other molten metal, but also by adhesives containing conductive materials, and the means of conductive connection does not need to be particularly limited. In addition, the relay substrate 50 used here can be used in addition to the following. Figure 1 In addition to the rigid plate-like shape shown in the figure, it may be a so-called FPC (flexible printed circuit board) having flexibility. However, by using a rigid plate-like shape instead of an FPC, it is advantageous in terms of the connection workability with the relay substrate 50, the lead pins 40, and the lead 38. For example, by connecting the lead 38 after connecting the relay substrate 50 to the lead pins 40, the lead is connected to the rigid substrate, which has the advantage of easy operation.

[0043] As described in the above-mentioned internal installation process, the lead pins 40 of this embodiment are supported and fixed in the extension direction of the leads 38 and the waterproof housing 20 and the housing 12. The sealing material 26 such as a polyurethane or epoxy resin filled in the waterproof housing 20 flows around the relay substrate 50 and enters between the housing 12 and solidifies, thereby being sealed in a liquid-tight manner in the pressure sensor unit 10. In addition to being fixed and supported in a liquid-tight manner by the sealing material 26 being closely bonded to the surface, the lead pins 40 are also ensured to be liquid-tight and maintained by the sealing glass 14 of the housing 12.

[0044] In addition, an adhesive 41 such as a silicone resin is applied to the entire circumference (area) of the surface of a portion of the lead pin 40 that covers the protruding portion protruding from the housing 12 (sealing glass 14). The adhesive 41 has the characteristic of bonding with a smaller bonding force than the sealing material 26 and the sealing glass 14 bonded to the surface of the lead pin 40.

[0045] The adhesive 41 is not limited to the portion protruding from the housing 12 as in the present embodiment on the surface of the lead pin 40 between the relay substrate 50 and the housing 12 (sealing glass 14). For example, the adhesive 41 may be applied to the relay substrate 50 side, or may be applied to the protruding / inserted portion of the lead pin 40 in the relay substrate 50 and the housing 12, or the entire protruding / penetrating surface. Moreover, the adhesive 41 is not limited to the entire circumference, and may be applied to one place or a part of a plurality of intermittent portions in the circumference to adjust the bonding force between the lead pin 40 and the sealing material 26. In addition, the adhesive 41 is not limited to being applied to a part of the plurality of lead pins 40 as in the present embodiment, and may be applied to all the lead pins 40 bonded and fixed to the housing 12 (sealing glass 14) (the purpose of this adjustment is the same in other embodiments described below).

[0046] Through this structure, when the bonding force of the sealing material 26 between the lead pin 40 and the relay substrate 50 and the housing 12 is suppressed due to the presence of the adhesive 41 so that, for example, the difference in the expansion / contraction amount of the lead pin 40 and the sealing material 26 corresponding to these linear expansion coefficients is large, a portion of the surface of the lead pin 40 that is bonded to the adhesive 41 is allowed to peel off and move relative to the sealing material 26 in the length direction.

[0047] In summary, in this structure, when the temperature of the load changes, especially when a difference in the amount of expansion / contraction of the sealing material 26 and the lead pin 40 occurs between the relay substrate 50 and the housing 12, stress is generated corresponding to the increase or decrease in the thickness of the sealing material 26 relative to the length of the lead pin 40. At this time, the lead pin 40 is intended to move in the longitudinal direction corresponding to the direction in which the sealing material 26 is pulled out or pressed into the sealing glass 14 of the housing 12, but unlike the lead pin 40 in which the sealing material 26 is bonded to the entire outer peripheral surface and is firmly fixed, in the lead pin 40 in the portion bonded to the sealing material 26 via the adhesive 41, the adhesive 41 and the sealing material 26 are peeled off and relative movement in the longitudinal direction is allowed.

[0048] Thus, the lead pin 40 can be allowed to move in accordance with the difference in the amount of expansion / contraction between the sealing material 26 and the lead pin 40 in the adhesive 41, and the stress that attempts to move the lead pin 40 in the direction of pulling out or pressing into the sealing glass 14 can be relieved / absorbed. Therefore, the generation of gaps and cracks between the sealing glass 14 and the lead pin 40 that cannot completely resist the stress that attempts to move the lead pin 40 can be prevented, and the deterioration of the liquid-tightness against the leakage of the pressure transmission medium from the sealing glass 14 side can be prevented. That is, the adhesive 41 functions as a coating material that restricts the bonding force between the lead pin 40 and the sealing material 26, and the bonding range thereof constitutes a restriction region (restriction unit) that suppresses the bonding force between the surface of the lead pin 40 and the sealing material 26.

[0049] Thus, in the pressure sensor 100 of the present embodiment, since the surface of the lead pin 40 between the separated housing 12 and the relay substrate 50 into which the sealing material 26 enters is coated with the adhesive 41 that suppresses the bonding force with the sealing material 26, it is possible to suppress the stress that causes the lead pin 40 to move in the length direction relative to the sealing glass 14 of the housing 12 due to temperature changes according to the difference in expansion / contraction between the sealing material 26 and the lead pin 40.

[0050] Therefore, in the pressure sensor 100 of the present embodiment, it is possible to avoid the occurrence of peeling cracks between the lead pins 40 and the sealing glass 14 and ensure liquid tightness, thereby improving reliability.

[0051] Among them, in this embodiment, since the sealing material 26 is filled in the shell 20 to ensure the liquid tightness around the relay substrate 50, the covered end of the lead 38 can be molded in the sealing material 26, which can prevent the so-called breathing effect in which moisture in the air penetrates through the core wire C due to temperature difference, pressure difference, etc., and thus can prevent the occurrence of short circuit, migration, etc. of the substrate circuit caused by condensation on the relay substrate 50, etc.

[0052] In addition, as described above, the restricted area for suppressing the adhesive force, i.e., the area where the adhesive 41 is applied, is not limited to the protruding portion of the lead pin 40 protruding from the sealing glass 14, but may be provided on the relay substrate 50 side, or may be provided on both the sealing glass side and the relay substrate side. For example, when the sealing material 26 filled between the housing 12 and the relay substrate 50 expands, the relay substrate 50 exerts stress on the lead pin 40 in the upward push direction of separation from the housing 12 through the sealing material 26. Among them, when the adhesive 41 is applied to the relay substrate 50 side, the sealing material 26 and the lead pin 40 cannot completely resist the stress at the applied portion and peel off. In addition, in the case of applying to both the sealing glass 14 and the relay substrate 50, the stress acting on the lead pin 40 can be suppressed by peeling off either or both of them. Therefore, the same effect as the above-mentioned embodiment can be exerted.

[0053] <Second Embodiment>

[0054] then, Figure 2 This is a diagram illustrating a pressure sensor according to a second embodiment of the present invention. Since this embodiment is substantially the same as the above-mentioned embodiment, the same reference numerals are used for the same structures and detailed description is omitted, and only the characteristic parts are described (the same also applies to other embodiments described below).

[0055] exist Figure 2 In the embodiment, the pressure sensor 100 includes a pressure sensor unit 10 that is the same as that of the first embodiment described above, and the lead pins 40 of this embodiment are coated with an adhesive 42 having the same properties as the adhesive 41, for example, on the surface of the protruding portions of the circular range (area) of the sealing glass 14 covering the housing 12 and the entire number (or a part) of the lead pins 40.

[0056] As described above, in the pressure sensor 100 of the present embodiment, the same effects as those of the above-described embodiments can be obtained, and the occurrence of peeling cracks between the lead pins 40 and the sealing glass 14 can be avoided while ensuring liquid tightness, thereby improving reliability.

[0057] <Third Embodiment>

[0058] then, Figure 3 It is a diagram for explaining a pressure sensor according to a third embodiment of the present invention.

[0059] exist Figure 3In the embodiment, the pressure sensor 100 includes the same pressure sensor unit 10 as the first embodiment described above, and the lead pin 40 of the present embodiment has a soldering surface formed of solder 43 in the range (region) covering the entire circumference of the surface of the protruding portion protruding from the housing 12 (sealing glass 14), and the surface of the solder 43 is covered with a flux that improves the wettability of the lead pin 40 to be soldered. Since the flux is present on the surface of the solder 43, the surface of the solder 43 is limited from being firmly bonded to the sealing material 26.

[0060] Through this structure, the bonding force of the sealing material 26 between the lead pin 40 and the relay substrate 50 and the housing 12 is suppressed by the flux on the surface of the solder 43. Similar to the above-mentioned embodiment, the situation that the lead pin 40 is firmly bonded to the sealing material 26 by the flux on the surface of the solder 43 is suppressed, and relative movement along the length direction is allowed. That is, the flux on the surface of the solder 43 of this embodiment constitutes a restriction area (restriction unit) that suppresses the bonding force with the sealing material 26, and constitutes a non-affinity material with low affinity with the sealing material 26. In addition, as long as there is no flux on the solder surface, at least the surface of the solder is smooth. Since it is difficult to obtain the so-called anchoring effect due to the smooth solder surface, the adhesion with the sealing material 26 is reduced and it may become the starting point of peeling, so it acts as a restriction area (restriction unit) that suppresses the bonding force with the sealing material.

[0061] As described above, in the pressure sensor 100 of the present embodiment, the same effects as those of the above-described embodiments can be obtained, and the occurrence of peeling cracks between the lead pins 40 and the sealing glass 14 can be avoided while ensuring liquid tightness, thereby improving reliability.

[0062] Among them, as other modes of this embodiment, although omitted from the figure, it is of course not limited to forming the solder 43 on the sealing glass 14 side, but can also be formed only on the relay substrate 50 side, or can also be formed on the relay substrate 50 side (this point is the same as the adhesive 41 and the solder 43 as mentioned above, and can also be applied to the structure with the sheet member described later). Furthermore, not only the flux precipitated on the surface of the solder 43 by brazing, but of course it can also be applied separately and located on the surface of the lead pin 40. In addition, it is not limited to providing the flux, etc. in order to suppress the bonding of the sealing material 26. The surface of the lead pin 40 can also be formed into a smooth surface that suppresses the adhesion of the sealing material 26, that is, by reducing the anchoring effect of the lead pin brought by the sealing material to reduce the contact (bonding) area and reduce the bonding force. The flux used in this embodiment has the advantage of being able to be applied during the brazing process. However, the limiting means for suppressing the bonding force is not limited to the flux listed here. As another method of reducing the affinity (bonding force) of the boundary between the solder 43 and the sealing material 26, a restriction area that suppresses the adhesion force with the sealing material 26 may be formed by applying various coatings with low affinity with the sealing material 26, such as resists, synthetic resin coatings, coating-based coatings, ion plating, plasma CVD, sputtering, etc., used in the insulation of electronic circuit boards. In the above example, a restriction unit that suppresses the bonding force by reducing the affinity for the sealing material is shown, but it is not limited to this example, and a restriction unit that suppresses the bonding force by peeling off the coating material relative to the lead pins may also be formed. Furthermore, while maintaining the bonding force / adhesion with the lead pins and the sealing material, it may also be a structure that becomes a restriction unit that suppresses the bonding force by the brittleness of the coating material or the cracking / cracking of the coating material itself.

[0063] <Fourth Embodiment>

[0064] then, Figure 4 It is a diagram for explaining a pressure sensor according to a fourth embodiment of the present invention.

[0065] exist Figure 4 In the embodiment, the pressure sensor 100 includes the same pressure sensor unit 10 as in the first to third embodiments described above, and the lead pins 40 of this embodiment can be loaded with an FPC (flexible printed circuit) sheet 51 as an auxiliary material that matches the shape of more than half of the circular shape of the sealing glass 14 covering the housing 12 and can be easily soldered to form solder 43. The FPC sheet 51 is made so that a pad 53 fused with solder can be formed around the through hole through which the lead pins 40 pass, and solder 43 can be formed on the surface of the lead pins 40 by an easy soldering operation.

[0066] According to this structure, in addition to being able to use the FPC sheet 51 to easily form the solder 43 that suppresses the bonding force between the relay substrate 50 and the housing 12 and the sealing material 26, the lead pin 40 can also form a gap between the lead pin 40 and the sealing glass 14 according to the thickness of the FPC sheet 51, thereby suppressing the bonding of the sealing material 26 to the surface of the lead pin 40 and reducing the generated stress, thereby suppressing the stress in the length direction of the lead pin 40.

[0067] Thus, in the pressure sensor 100 of this embodiment, in addition to the same effects as the above-mentioned embodiment, solder 43 can be easily formed on the lead pin 40, which can avoid peeling cracks between the lead pin 40 and the sealing glass 14 and ensure liquid tightness, thereby improving reliability.

[0068] As another embodiment of this embodiment, Figure 5 As shown, this embodiment can also be applied to a pressure sensor 100 in which mounting parts 50J having various functions are mounted on a relay substrate 50 to form various circuits for adjusting electrical signals between the lead 38 and the sensor chip 11. This other embodiment is not limited to this embodiment, and can of course also be applied to other embodiments described above or later.

[0069] As another method of the present embodiment, although not shown in the figure, in addition to the method of covering the sealing glass 14 with auxiliary materials such as the FPC sheet 51, the FPC sheet 51 (sheet component) can also be arranged in close contact with the lead pin 40 insertion side of the relay substrate 50, that is, the side of the relay substrate 50 opposite to the sealing glass 14 as described above, thereby forming a limiting unit that acts as a limiting component to suppress the bonding force. By setting it in this way, a gap is formed between the sealing material 26 and the relay substrate 50, which can suppress the bonding of the sealing material 26 with the surface of the lead pin 40 and reduce the stress generated, and can suppress the stress of the protruding portion in the sealing glass 14 in the length direction of the lead pin 40. In addition, Figure 4 As shown in FIG. 1 , the FPC sheet 51 has a shape that covers about half of the exposed surface of the sealing glass 14 and about half of the lead pins 40 that penetrate therethrough, but the shape is not limited thereto. It may also be a shape that corresponds to the protruding / inserted portion of the lead pins including the entire exposed sealing glass surface and the relay substrate side. By having a shape that corresponds to all the lead pins, the FPC sheet can be mounted without directionality relative to the lead pins, thereby improving workability.

[0070] <Fifth Embodiment>

[0071] then, Figure 6 It is a diagram for explaining a pressure sensor according to a fifth embodiment of the present invention.

[0072] exist Figure 6 In the embodiment, the pressure sensor 100 includes the same pressure sensor unit 10 as in the first and third embodiments described above, and the lead pins 40 of this embodiment are provided with an elastic member 45 made of, for example, a rubber material in a range (region) covering the entire circumference of the surface of the protruding portion protruding from the housing 12 (sealing glass 14). The elastic member 45 is coated with a rubber material or the like in a manner covering the surface of the lead pins 40, or is covered with a rubber tube, and restricts the sealing material 26 from being joined.

[0073] With this structure, the lead pin 40 can limit the bonding force between the relay substrate 50 and the housing 12 and the sealing material 26 acting on the lead pin 40 at the location where the elastic member 45 is formed, and allow the lead pin 40 to move relatively in the length direction at the location where the elastic member 45 is formed. That is, the elastic member 45 of this embodiment functions as a limiting member that sets a limiting area for suppressing the bonding force with the sealing material 26 at the location where the elastic member 45 is set, and constitutes a limiting unit. The elasticity of the elastic member 45 such as rubber provided functions in a manner to alleviate the stress of the lead pin 40 protruding from the sealing glass 14 due to the thermal contraction and expansion of the sealing material 26.

[0074] Thus, in the pressure sensor 100 of this embodiment, the same effects as those of the first and third embodiments can be obtained, and the occurrence of peeling cracks between the lead pins 40 and the sealing glass 14 can be avoided while ensuring liquid tightness, thereby improving reliability.

[0075] <Sixth Implementation Method>

[0076] then, Figure 7 It is a diagram for explaining a pressure sensor according to a sixth embodiment of the present invention.

[0077] exist Figure 7 In the embodiment, the pressure sensor 100 includes the same pressure sensor unit 10 as in the first to fifth embodiments described above, and the lead pin 40 of this embodiment is provided with, for example, an elastic sheet member 46 in a circular range (region) of the sealing glass 14 covering the housing 12. The elastic sheet member 46 is formed in a sheet shape of a desired thickness so as to have the same characteristics as the elastic member 45 and function as a restriction region / member, i.e., a restriction unit. The elastic sheet member 46 is provided so as to penetrate all (or part) of the lead pin 40 and be located on the surface of the protruding portion protruding from the sealing glass 14.

[0078] Thus, in the pressure sensor 100 of the present embodiment, the same effects as those of the fifth embodiment can be obtained, and the occurrence of peeling cracks between the lead pins 40 and the sealing glass 14 can be avoided while ensuring liquid tightness, thereby improving reliability.

[0079] In addition, as another aspect of the fifth and sixth embodiments, the rubber material is used as an example for explanation, but the invention is not limited thereto. A coating material such as an adhesive having an adhesive function may be used to have a lower rigidity than the sealing material (deformation is larger than the sealing material and flexibility is provided), and the lead pin 40 may be allowed to move relative to the longitudinal direction by elastic deformation. Alternatively, a crack may be generated inside the lead pin 40 by the movement of the lead pin 40 to allow the relative movement. In addition, as another aspect of the fifth and sixth embodiments, the restriction area / component (restriction unit) that suppresses the adhesive force is arranged at the protruding portion of the lead pin 40 protruding from the sealing glass 14 or within the circular range covering the upper surface of the sealing glass 14, the same effect can be achieved even if it is arranged at the insertion portion side of the lead pin 40 located on the opposite surface side of the sealing glass 14 in the relay substrate 50.

[0080] <First other method>

[0081] Furthermore, as a first other aspect of the above embodiment, in the above embodiment, the structure connected to the external device A via the lead wire 38 is described as an example, but it is not limited to this. Figure 8 As shown, the pressure sensor 100 can be easily connected to the external device A by providing a connector 80 on the opposite side of the joint member 30. Specifically, the connector 80 is connected and supported by the housing 12 by inserting a male connector 81 that can be connected to a female connector (not shown) on the side of the external device A into the straight cylindrical waterproof housing 20', and the male connector 81 conducts and connects the connection terminal 83 to the relay substrate 50 via the bonding wire 83w, thereby realizing easy attachment and detachment of the external device A with respect to the sensor chip 11 via the lead pin 40. In addition, the oil filling tube 89 in the figure is used when silicone oil as a pressure transmission medium is filled into the liquid sealing chamber LR in which the pressure sensor chip 11 is provided, and is sealed after filling.

[0082] <Second other method>

[0083] In addition, as a second other mode of the above-mentioned embodiment, in the above-mentioned embodiment, the case where the liquid seal chamber LR is filled with silicone oil as a pressure transmission medium using an oil filling tube, and the case where a plurality of lead pins are insulated and sealed and fixed to the housing using an integrated sealing glass are described as an example, but the present invention is not limited to this. For example, Fig. 9As shown, a pressure sensor 100 having a liquid seal chamber LR different from the housing 12 may be used. Specifically, the housing 62 in which the cover 28 is inverted upside down and the periphery of the cover 28 are connected to each other in a liquid-tight manner with the diaphragm 32 sandwiched therebetween, thereby forming the liquid seal chamber LR. In this structure, silicone oil as a pressure transmission medium may be filled into the liquid seal chamber LR through a filling hole 62h penetrating the housing 62, and the filling hole 62h may be closed by a plug member 69 after the filling. In the case of this structure, the lead pin 40 connected to the pressure sensor chip 11 passes through a through hole 63h opened in the housing 62 and is liquid-tightly sealed and supported by the sealing glass 63. That is, a structure in which the lead pin 40 is individually insulated and sealed and fixed by the sealing glass 63 may be used.

[0084] The scope of the present invention is not limited to the exemplary embodiments described in the drawings, but includes all embodiments that bring about the same effects as the purpose of the present invention. Furthermore, the scope of the present invention is not limited to the combination of the features of the invention defined by each claim, but can be divided by all required combinations of all the specific features disclosed.

[0085] Explanation of symbols

[0086] 10—pressure sensor unit; 11—pressure sensor chip; 12—housing; 14—sealing glass; 20—waterproof housing; 26—sealing material; 30—connector component; 38—lead; 40—lead pin; 41, 42—adhesive; 45—elastic component; 46—elastic sheet component; 50—relay substrate; 51—FPC sheet; 100—pressure sensor; A—external device; LR—liquid seal chamber; PR—pressure chamber.

Claims

1. A pressure sensor, wherein a sensor for detecting the pressure of a measurement object is connected to a relay substrate and is housed in a housing together with the relay substrate in a liquid-tight manner using a sealing material, wherein: The sensor is disposed on a sensor fixing member, and the sensor fixing member has a pressure chamber that receives the pressure of a measurement object. The relay substrate is configured to be conductively connected to the sensor provided 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 interposed between the sensor and the external device. The pin member protrudes from the sensor fixing member and is connected to the separated relay substrate, and is bonded to the sealing material entering between the sensor fixing member and the relay substrate. A restriction unit for suppressing a bonding force between the pin member and the sealing material is arranged between the relay substrate and the sensor fixing member.

2. The pressure sensor according to claim 1, characterized in that: A restriction region is arranged on a pin-shaped surface of the pin member as the restriction means for suppressing a bonding force with the sealing material.

3. The pressure sensor according to claim 1, characterized in that: The pin member is fixed in the sensor fixing member in an embedded state and is directly conductively connected to the relay substrate. The pin-shaped surface of the pin member is bonded to the sealing material entering between the sensor fixing member and the relay substrate.

4. The pressure sensor according to claim 1, characterized in that: The restriction unit is located entirely or partially between the sensor fixing member and the relay substrate in the pin shape surface of the pin member.

5. The pressure sensor according to claim 4, characterized in that: The limiting unit is arranged at a position close to one or both of the sensor fixing member and the relay substrate on the pin shape surface of the pin member.

6. The pressure sensor according to claim 1, characterized in that: The plurality of pin components are embedded and fixed in the sensor fixing component and are conductively connected to the relay substrate. The limiting unit is disposed on all or part of the plurality of pin members.

7. The pressure sensor according to claim 1, characterized in that: The restricting means is configured to arrange a coating material having a smaller bonding force with the pin member than the sealing material on a pin-shaped surface.

8. The pressure sensor according to claim 1, characterized in that: The restriction unit is configured to be formed on a pin-shaped surface of the pin member in a shape that reduces a bonding force with the sealing material.

9. The pressure sensor according to claim 1, characterized in that: The restriction unit is configured by arranging an elastic material on a pin-shaped surface of the pin member.

10. The pressure sensor according to claim 1, characterized in that: The restricting means is configured by disposing a coating material having a lower rigidity than the sealing material on a pin-shaped surface of the pin member.

11. The pressure sensor according to claim 1, characterized in that: The restriction unit is configured to arrange a non-affinity material having a low affinity with the sealing material on a pin shape surface of the pin member.

12. The pressure sensor according to claim 1, characterized in that: The limiting means is composed of a sheet member that covers a part or all of at least one of the protruding portion of the pin member in the sensor fixing member and the insertion portion of the pin member in the relay substrate. The sheet member is arranged to be in contact with one or both of the sensor fixing member and the relay substrate.

13. The pressure sensor according to claim 11, characterized in that: The limiting means is configured so that flux for soldering is located on the outermost surface of the pin shape of the pin member.

14. The pressure sensor according to claim 13, characterized in that: The sensor fixing member is provided with an auxiliary material having an opening through which the pin member can protrude and formed with a pattern for soldering the pin member, The limiting unit is configured so that the flux is located at the outermost surface of the solder surface of the pattern of the auxiliary material.

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