Pressure sensor, pressure measuring device, and method for manufacturing a pressure measuring device

Abstract

To provide a pressure sensor preventing a connection part between a pressure guidance pipe and a washer from being corroded.SOLUTION: A pressure sensor includes: first and second pressure guidance pipes 13, 14 filled with a pressure transmission medium; a sensor case in which one end of the first and second pressure guidance pipes 13, 14 is soldered; and a sensor chip housed in the sensor case. The pressure sensor also includes first and second washers 15, 16 that have a through hole 35 into which the other ends of the first and second pressure guidance pipes 13, 14 are inserted while the tips of the first and second pressure guidance pipes 13, 14 inserted into the through hole 35 are welded. A welding body 36 in which the first and second washers 15, 16 are welded to the first and second pressure guidance pipes 13, 14 is plated with gold. An insertion opening 75 into which the first and second pressure guidance pipes 13, 14 are inserted in the gold-plated through hole 35 is sealed with a sealing material 74.SELECTED DRAWING: Figure 14

Description

Technical Field

[0001] The present invention relates to a pressure sensor having a gold-plated pressure guiding pipe, a pressure measuring device, and a method for manufacturing the pressure measuring device.

Background Art

[0002] Conventionally, as a pressure sensor, there is, for example, one described in Patent Document 1. Patent Document 1 discloses a pressure sensor 1 shown in FIG. 15. In this pressure sensor 1, two pressure guiding pipes 3 are connected to a sensor chip 2. These pressure guiding pipes 3 penetrate the bottom portion 4a of a sensor case 4. The pressure guiding pipes 3 are filled with an enclosed liquid as a pressure transmission medium. Further, the sensor chip 2 is adhered to the bottom portion 4a of the sensor case 4. In this type of pressure sensor 1, the sensor chip 2 is often formed of silicon, and the sensor case 4 is often formed of ceramics.

[0003] The tip of the pressure guiding pipe 3 is connected to the body of a pressure measuring device (not shown), and the pressure of the fluid to be measured is transmitted from a pressure guiding path provided in the body through the pressure transmission medium. In order to connect the pressure guiding pipe 3 to the body of the pressure measuring device, for example, a washer described in Patent Document 2 can be used. The washer is welded to the opening portion of the pressure guiding path in a state where the pressure guiding pipe 3 is inserted and coupled. The washer and the pressure guiding pipe 3 are coupled by inserting the pressure guiding pipe into a through hole formed in the washer and welding the tip of the pressure guiding pipe 3 and the front end surface of the washer.

[0004] It is desirable to solder the portion where the pressure sensing pipe 3 penetrates the bottom 4a of the ceramic sensor case 4 in order to seal the inside of the sensor case 4. The pressure sensing pipe 3 is often made of stainless steel to increase its pressure resistance. Conventionally, in order to solder a pressure sensing pipe made of stainless steel to a ceramic material, the pressure sensing pipe 3 is gold-plated and the ceramic material is metallized to ensure the wettability of the solder. That is, in order to form the pressure sensor 1 shown in Figure 15, a washer is welded to the pressure sensing pipe 3, a welded body is gold-plated, and then the pressure sensing pipe 3 is soldered to the sensor case 4. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2021-92489 [Patent Document 2] Japanese Patent Publication No. 2021-171795 [Overview of the project] [Problems that the invention aims to solve]

[0006] However, as mentioned above, when gold plating is applied to a welded body consisting of a pressure sensing pipe and a washer, there is a risk of corrosion at the connection point between the pressure sensing pipe and the washer. This is because, during the plating process, the plating solution adheres to the tiny gap between the through-hole of the washer and the pressure sensing pipe, and even after cleaning following the plating, it remains as residue. This residue contains components (chlorides) that promote corrosion, making it prone to corroding the pressure sensing pipe when exposed to a high-humidity atmosphere. As the corrosion of the pressure sensing pipe progresses, the pipe can melt, leading to leakage of the pressure transmission medium and deterioration of pressure resistance.

[0007] The object of the present invention is to provide a pressure sensor, a pressure measuring device, and a method for manufacturing a pressure measuring device in which the connection portion between the pressure sensing pipe and the washer does not corrode. [Means for solving the problem]

[0008] To achieve this objective, the pressure sensor according to the present invention comprises a pressure-sensing pipe filled with a pressure-transmitting medium, a sensor case soldered to which one end of the pressure-sensing pipe passes through, a sensor chip housed in the sensor case for detecting the pressure of the pressure-transmitting medium, and a washer having a through-hole into which the other end of the pressure-sensing pipe is inserted, with the tip of the pressure-sensing pipe inserted into the through-hole welded to it. The welded body formed by welding the washer to the pressure-sensing pipe is gold-plated, and the insertion opening in the gold-plated through-hole into which the pressure-sensing pipe is inserted is sealed with a sealing material.

[0009] In the pressure sensor of the present invention, the through hole of the washer may be formed by a first hole into which the tip of the other end of the pressure sensing pipe is inserted, and a second hole having a larger diameter than the first hole.

[0010] The pressure measuring device according to the present invention is a pressure measuring device equipped with a pressure sensor, comprising: a body having a pressure receiving chamber for receiving the pressure of a fluid to be measured and a sensor connection port communicating with the pressure receiving chamber via a pressure guiding path; a substrate holder attached to the body; and a substrate on which the sensor case of the pressure sensor is mounted and which is mounted upright on the substrate holder at a position adjacent to the sensor connection port, wherein the substrate holder has a hole formed at a position corresponding to the sensor connection port through which the washer can be inserted, and a groove extending from the hole to the substrate, the pressure guiding pipe of the pressure sensor is inserted into the groove, and the washer is welded to the sensor connection port with the washer inserted into the hole, and the sealing material is filled in the area from the washer through the hole and the groove to the substrate.

[0011] The method for manufacturing a pressure measuring device according to the present invention comprises the steps of: forming a body having an opening for a sensor connection port that communicates with a pressure receiving chamber that receives the pressure of a fluid to be measured; inserting a pressure sensing pipe through a through hole in a washer connected to the sensor connection port and welding it to form a welded body; gold plating the welded body; soldering the end of the gold-plated pressure sensing pipe opposite to the washer through a sensor case; housing a pressure detection sensor chip inside the sensor case to form a pressure sensor; welding the washer to the sensor connection port; and sealing the insertion opening of the through hole into which the pressure sensing pipe is inserted with a sealing material. [Effects of the Invention]

[0012] According to the present invention, since the through-hole of the washer into which the pressure sensing pipe is inserted is sealed with a sealing material, the residue from the plating process inside the through-hole is not exposed to the outside air. Therefore, it is possible to provide a pressure sensor and pressure measuring device in which the connection portion between the pressure sensing pipe and the washer does not corrode.

[0013] According to the manufacturing method of the pressure measuring device of the present invention, since the washer can be welded to the body of the pressure detection device before the sealing material is filled, the sealing material does not get in the way when welding the washer to the body. Therefore, even though the step of filling the sealing material is increased compared to the conventional method, the productivity of the pressure measuring device can be kept high. [Brief explanation of the drawing]

[0014] [Figure 1] Figure 1 is a perspective cross-sectional view showing a cutaway of the sensor case portion of the pressure sensor according to the present invention. [Figure 2] Figure 2 is a cross-sectional view of the pressure sensing pipe and washer. [Figure 3] Figure 3 is a perspective cross-sectional view of the pressure measuring device according to the present invention. [Figure 4] Figure 4 is an exploded perspective view of the pressure measuring device. [Figure 5]FIG. 5 is an exploded perspective view of the pressure measuring device. [Figure 6] FIG. 6 is a flowchart showing a method for manufacturing the pressure measuring device. [Figure 7] FIG. 7 is a cross-sectional view for explaining the step of welding a washer to the pressure guiding pipe. [Figure 8] FIG. 8 is a cross-sectional view for explaining the step of plating the welded body with gold. [Figure 9] FIG. 9 is a cross-sectional view showing the state where the welded body is cleaned after gold plating. [Figure 10] FIG. 10 is a cross-sectional view for explaining the step of soldering the pressure guiding pipe to the sensor case body. [Figure 11] FIG. 11 is a cross-sectional view for explaining the step of forming the pressure sensor. [Figure 12] FIG. 12 is a perspective cross-sectional view for explaining the step of welding the washer to the body. [Figure 13] FIG. 13 is a perspective cross-sectional view for explaining the step of filling the sealing material. [Figure 14] FIG. 14 is an enlarged cross-sectional view showing the main part. [Figure 15] FIG. 15 is a cross-sectional view of a conventional pressure sensor.

DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, an embodiment of the pressure sensor, the pressure measuring device, and the method for manufacturing the pressure measuring device according to the present invention will be described in detail with reference to FIGS. 1 to 13. The pressure sensor 11 shown in FIG. 1 includes a sensor case 12 drawn at the top in FIG. 1, first and second pressure guiding pipes 13, 14 having one end connected to the sensor case 12, and first and second washers 15, 16 connected to the other ends of the first and second pressure guiding pipes 13, 14.

[0016] The sensor case 12 is formed by a bottomed rectangular tubular sensor case body 17 made of ceramic material and a lid 18 that closes the opening of the sensor case body 17, and houses a sensor chip 19 inside. Multiple soldering pads 20 are provided on the bottom surface 17a of the sensor case body 17. Although not shown in the figure, these soldering pads 20 are electrically connected to the electrodes of the sensor chip 19 via a conductor formed inside the sensor case body 17 and bonding wires or the like.

[0017] The first pressure sensing pipe 13 and the second pressure sensing pipe 14 are each made of stainless steel, bent into a predetermined shape, and connected to the sensor case body 17 with the first and second washers 15 and 16 welded to them. The first and second pressure sensing pipes 13 and 14 extend into the sensor case 12 through through holes 21 formed in the bottom wall 17b of the sensor case body 17 and are soldered to the bottom wall 17b of the sensor case body 17. The solder at the soldered portion between the first and second pressure sensing pipes 13 and 14 and the sensor case body 17 is indicated by reference numeral 22 in Figure 1.

[0018] The tip portions of the first and second pressure sensing pipes 13 and 14 on the sensor case body 17 side are bonded to the sensor chip 19. After the pressure sensor 11 is completed, a pressure transmission medium 23 (see Figure 3) is injected into the first and second pressure sensing pipes 13 and 14. The sensor chip 19 detects the differential pressure between the pressure of the pressure transmission medium 23 in the first pressure sensing pipe 13 and the pressure of the pressure transmission medium 23 in the second pressure sensing pipe 14. The outer surfaces of the first and second pressure sensing pipes 13 and 14 are gold-plated so that solder 22 can spread between them and the sensor case body 17. Although not shown in the figure, the area around the through hole 21 in the bottom surface 17a of the sensor case body 17 is metallized so that solder can spread between it and the first and second pressure sensing pipes 13 and 14.

[0019] The first and second washers 15 and 16 are for attaching the pressure sensor 11 to the body 32 of the pressure measuring device 31 (see Figure 3), which will be described later. They are formed by a disc-shaped disc portion 33 (see Figure 2(A)) and a cylindrical portion 34 protruding from the axial center of the disc portion 33. As shown in Figure 2(A), through holes 35 are formed in the axial centers of the first and second washers 15 and 16 into which the other ends of the first and second pressure sensing pipes 13 and 14 are inserted. In this embodiment, the through hole 35 is formed by a first hole 35a into which the leading ends of the other ends of the first and second pressure sensing pipes 13 and 14 are inserted, and a second hole 35b with a larger diameter than the first hole 35a. The first hole 35a and the second hole 35b are each formed by machining so that they lie on the same axis.

[0020] As shown in Figure 2(B), the tip portions of the cylindrical parts 34 of the first and second washers 15 and 16 are crimped radially inward with the first and second pressure-sensing pipes 13 and 14 inserted into the through holes 35. This crimping creates a reduced-diameter portion 34a in the cylindrical part 34, fixing the first and second pressure-sensing pipes 13 and 14 to the first and second washers 15 and 16. As shown in Figure 2(C), the first and second pressure-sensing pipes 13 and 14 are fixed to the cylindrical portion 34, and a laser beam L is irradiated onto the boundary between the tip and the cylindrical portion 34, thereby welding them to the cylindrical portion 34 by laser welding. The gold plating described above is applied to the welded body 36 formed by welding the first and second washers 15 and 16 to the first and second pressure-sensing pipes 13 and 14 in this manner.

[0021] The pressure sensor 11 described above is used when assembled into the pressure measuring device 31 shown in Figure 3. As shown in Figure 3, the pressure measuring device 31 is constructed by assembling various functional components into a body 32 sandwiched between a first pipe 41 and a second pipe 42. The inside of the first pipe 41 is filled with the first fluid to be measured 43, and the inside of the second pipe 42 is filled with the second fluid to be measured 44 It is filled with it. The body 32 has a pressure-receiving section 45 to which the first and second pipes 41 and 42 are connected, and a bottomed cylindrical detection section 46, which is shown at the top in Figure 3. The bottom of the detection section 46 is connected to the pressure-receiving section 45.

[0022] The pressure receiving section 45 is provided with a first pressure receiving diaphragm 51 that is in contact with the first fluid to be measured 43, and a second pressure receiving diaphragm 52 that is in contact with the second fluid to be measured 44. The pressure receiving section 45 also has a first pressure receiving chamber 53 in which the first pressure receiving diaphragm 51 forms part of the wall, and a second pressure receiving chamber 54 in which the second pressure receiving diaphragm 52 forms part of the wall. The first pressure receiving chamber 53 is connected to the first sensor connection port 56 of the detection section 46 via a first pressure guiding path 55 formed in the body 32.

[0023] The second pressure-receiving chamber 54 is connected to the second sensor connection port 58 of the detection unit 46 via a second pressure-conducting path 57 formed within the body 32. The pressure transmission path from the first and second pressure-receiving chambers 53, 54 to the first and second sensor connection ports 56, 58 is filled with a pressure transmission medium 23. The first and second sensor connection ports 56 and 58 open to the inner bottom surface 46a of the detection unit 46. The first washer 15 of the pressure sensor 11 described above is welded to the first sensor connection port 56, and the second washer 16 is welded to the second sensor connection port 58.

[0024] A circuit board holder 61 is attached to the detection unit 46 by mounting bolts 62. The substrate holder 61 has a plate-shaped base 61a superimposed on the inner bottom surface 46a of the detection unit 46, and a pair of arm portions 61b protruding from both sides of the base 61a. A substrate 63 is attached to one end of the base 61a by a mounting screw 64 (see Figures 4 and 5). The substrate 63 is mounted to the substrate holder 61 in a position extending in the axial direction (up and down direction in Figure 3) of the detection unit 46, which is formed in a bottomed cylindrical shape. Furthermore, the substrate 63 is mounted to the substrate holder 61 such that its component mounting surface 63a (see Figure 5) is located on the opposite side from the first and second sensor connection ports 56 and 58. By being mounted to the substrate holder 61, the substrate 63 is positioned upright adjacent to the first and second sensor connection ports 56 and 58.

[0025] The sensor case 12 of the pressure sensor 11 is mounted on the component mounting surface 63a of the circuit board 63. The pressure sensor 11 is mounted on the circuit board 63 with the first and second pressure sensing pipes 13 and 14 passing through a notch 65 (see Figure 4) formed at the end of the circuit board 63 on the circuit board holder side. A cover 66 that covers the component mounting surface 63a of the circuit board 63 is attached to the circuit board holder 61 together with the circuit board 63. The cover 66 is formed in a box shape that covers the component mounting surface 63a of the circuit board 63, and one end of the cover 66 is attached to the circuit board holder 61 by a mounting screw 64 that is the same as that used for the circuit board 63. The other end of the cover 66 is locked to the circuit board 63 by a plurality of locking pieces 67.

[0026] As shown in Figure 12, the base 61a of the substrate holder 61 has holes 71 and 72 formed to allow insertion of first and second washers 15 and 16 at positions corresponding to first and second sensor connection ports 56 and 58, and a groove 73 extending from these holes 71 and 72 to the substrate 63. The first and second washers 15 and 16 of the pressure sensor 11 are inserted into the holes 71 and 72. These first and second washers 15 and 16 are welded to the first and second sensor connection ports 56 and 58 by resistance welding. The first and second pressure sensing pipes 13 and 14 of the pressure sensor 11 are inserted into the groove 73.

[0027] In the area from the first and second washers 15 and 16 through the holes 71 and 72 and groove 73 to the substrate 63, a sealing material 74 is filled by potting, as shown in Figure 13, with the first and second washers 15 and 16 welded to the body 32. Figures 3 and 12 omit the sealing material 74. The sealing material 74 is made of a material that does not allow moisture to pass through. For example, silicone resin, urethane resin, fluororesin, or solder can be used as the sealing material 74. The sealing material 74 seals the insertion opening 75 {see Figure 2(C)} of the through hole 35 formed in the first and second washers 15 and 16 into which the first and second pressure sensing pipes 13 and 14 are inserted.

[0028] Next, the method for manufacturing the pressure measuring device 31 configured as described above will be explained using the flowchart shown in Figure 6. In order to manufacture the pressure measuring device 31, first, the body 32 and the accessory parts are formed (step S1). The accessory parts include the first and second pressure sensing pipes 13 and 14 of the pressure sensor 11, the first and second washers 15 and 16, the sensor case body 17, the lid 18, the sensor chip 19, the substrate holder 61 and the cover 66. Then, as shown in Figures 7(A) and (B), the first and second washers 15 and 16 are welded to the first and second pressure sensing pipes 13 and 14 to form the welded body 36 (step S2).

[0029] Next, as shown in Figure 8, the welded body 36 is immersed in the plating bath 81 to gold plate the welded body 36 (step S3). After the gold plating is completed, as shown in Figure 9, the welded body 36 is cleaned with, for example, a cleaning solution 82. Then, as shown in Figure 10, the first and second pressure sensing pipes 13 and 14 are inserted through the through holes 21 of the sensor case body 17 and soldered to the sensor case body 17 (step S4). Next, as shown in Figure 11, the sensor chip 19 is inserted into the sensor case body 17 and the first and second pressure sensing pipes 13 and 14 are bonded to the sensor chip 19. Then, the conductor of the sensor case body 17 and the sensor chip 19 are electrically connected, for example, by bonding wire, and the lid 18 is joined to the sensor case body 17 to seal the inside of the sensor case 12.

[0030] The pressure sensor 11 is formed by sealing the inside of the sensor case 12 in this way (step S5). The sensor chip 19 can be attached to the first and second pressure sensing pipes 13 and 14 in one of the following two ways. The first method is to attach the sensor chip 19 to the first and second pressure sensing pipes 13 and 14 before they are soldered to the sensor case body 17. The second method is to attach the sensor chip 19 to the first and second pressure sensing pipes 13 and 14 after they have been soldered to the sensor case body 17.

[0031] After the pressure sensor 11 is formed, the sensor case 12 is mounted on the substrate 63, and the substrate 63 is attached to the substrate holder 61 together with the cover 66. At this time, the first and second pressure sensing pipes 13 and 14 are inserted into the grooves 73 of the substrate holder 61, and the first and second washers 15 and 16 are inserted into the holes 71 of the substrate holder 61. Then, as shown in Figure 12, the substrate holder 61 is fixed to the body 32. At this time, the first and second washers 15 and 16 are placed on top of the first sensor connection port 56 and the second sensor connection port 58 of the body 32. Then, the first and second washers 15 and 16 are welded to the first and second sensor connection ports 56 and 58 of the body 32 (step S6). This welding is performed by resistance welding by pressing a rod-shaped resistance welding electrode 83, shown by the dashed line in Figure 12, against the first and second washers 15 and 16. This electrode 83 is passed through holes 71 and 72 in the substrate holder and brought into contact with the first and second washers 15 and 16.

[0032] Subsequently, as shown in Figure 13, the holes 71, 72 and groove 73 of the substrate holder 61 are filled with sealing material 74 by potting, and the first and second pressure-sensing pipes 13, 14 and the first and second washers 15, 16 are embedded in the sealing material 74. By potting the sealing material 74 in this way, the insertion openings 75 of the through holes 35 of the first and second washers 15, 16 are sealed by the sealing material 74, as shown in Figure 14 (step S7). After filling with the sealing material 74 in this manner, the pressure transmission medium 23 is injected into the first and second pressure sensing paths 55 and 57 from inlets (not shown), and the pressure transmission path from the first and second pressure receiving chambers 53 and 54 to the sensor chip 19 is filled with the pressure transmission medium 23, thereby completing a pressure measuring device 31 capable of detecting the differential pressure between the first and second fluids to be measured.

[0033] With the pressure sensor 11 and pressure measuring device 31 configured in this way, the through holes 35 of the first and second washers 15 and 16 into which the first and second pressure sensing pipes 13 and 14 are inserted are sealed by the sealing material 74, so that any residue remaining in the through holes 35 after gold plating is not exposed to the outside air. Therefore, according to this embodiment, it is possible to provide a pressure sensor and pressure measuring device in which the connection portion between the pressure sensing pipe and the washer does not corrode.

[0034] In the pressure sensor 11 according to this embodiment, the through holes 35 of the first and second washers 15 and 16 are formed by a first hole 35a into which the other ends of the first and second pressure sensing pipes 13 and 14 are inserted, and a second hole 35b having a larger diameter than the first hole 35a. Therefore, the cleaning solution 82 can easily enter the second hole 35b during the cleaning process after gold plating is complete, allowing for easy cleaning of the through hole 35 and reducing residue after gold plating. Consequently, a pressure sensor that is even less susceptible to corrosion can be realized.

[0035] The pressure measuring device 31 according to this embodiment includes a body 32 having first and second pressure receiving chambers 53, 54 that receive the pressure of first and second fluids to be measured 43, 44, and first and second sensor connection ports 56, 58 that communicate with the first and second pressure receiving chambers 53, 54 via first and second pressure guiding paths 55, 57. The pressure measuring device 31 also includes a substrate holder 61 attached to the body 32 and a substrate 63 on which the sensor case 12 of the pressure sensor 11 is mounted and which is mounted upright on the substrate holder 61 at a position adjacent to the first and second sensor connection ports 56, 58.

[0036] The substrate holder 61 has holes 71 and 72 formed to allow the insertion of first and second washers 15 and 16 at positions corresponding to the first and second sensor connection ports 56 and 58, and a groove 73 extending from the holes 71 and 72 to the substrate 63. The first and second pressure sensing pipes 13 and 14 of the pressure sensor 11 are inserted into the groove 73, and the first and second washers 15 and 16 are welded to the first and second sensor connection ports 56 and 58 with the washers inserted into the holes 71 and 72. The sealing material 74 fills the area from the first and second washers 15 and 16 through the holes 71 and 72 and the groove 73 to the substrate 63. Therefore, in addition to sealing the insertion openings 75 of the through holes 35 of the first and second washers 15 and 16, the first and second pressure-sensing pipes 13 and 14 and the first and second washers 15 and 16 can be embedded in the sealing material 74 and protected.

[0037] The manufacturing method for the pressure measuring device 31 according to this embodiment includes the steps of: step S1 forming the body 32 of the pressure measuring device 31; step S2 forming the welded body 36; step S3 applying gold plating to the welded body 36; and step S4 soldering the first and second pressure sensing pipes 13 and 14 to the sensor case body 17. The manufacturing method also includes the steps of: step S5 forming the pressure sensor 11 by housing the pressure detection sensor chip 19 inside the sensor case 12; step S6 welding the first and second washers 15 and 16 to the first and second sensor connection ports 56 and 58; and step S7 sealing the insertion ports 75 of the through holes 35 of the first and second washers 15 and 16 with a sealing material 74. According to this manufacturing method for the pressure measuring device 31, the first and second washers 15 and 16 can be welded to the body 32 of the pressure measuring device 31 before the sealant 74 is filled in. Therefore, the sealant 74 does not get in the way when welding the first and second washers 15 and 16 to the body 32. Consequently, even though the step of filling the sealant 74 is increased compared to the conventional method, the productivity of the pressure measuring device 31 can be kept high.

[0038] The through holes 35 of the first and second washers 15 and 16 according to the above-described embodiment have a second hole 35b that includes a large opening insertion opening 75. However, the through hole 35 can be formed so that the hole diameter is constant from one end to the other. [Explanation of symbols]

[0039] 11...Pressure sensor, 12...Sensor case, 13...First pressure sensing pipe, 14...Second pressure sensing pipe, 19...Sensor chip, 15...First washer, 16...Second washer, 23...Pressure transmission medium, 31...Pressure measuring device, 32...Body, 35...Through hole, 35a...First hole, 35b...Second hole, 36...Welded body, 43...First fluid to be measured, 44...Second fluid to be measured, 53...First pressure receiving chamber, 54...Second pressure receiving chamber, 55...First pressure sensing path, 56...First sensor connection port, 57...Second pressure sensing path, 58... S1...Step to form the pressure measuring device body, S2...Step to form the welded body, S3...Step to gold plate the welded body, S4...Step to solder the pressure sensing pipe to the sensor case, S5...Step to form the pressure sensor, S6...Step to weld the first and second washers to the sensor connection port, S7...Step to seal the insertion port of the through hole with the sealing material.

Claims

1. A pressure-transmitting pipe filled with a pressure-transmitting medium, A sensor case, in which one end of the pressure sensing pipe is soldered through, A sensor chip housed in the aforementioned sensor case for detecting the pressure of the pressure transmission medium, The system comprises a washer having a through hole into which the other end of the pressure sensing pipe is inserted, and the tip of the pressure sensing pipe inserted into the through hole is welded to the washer, The welded body formed by welding the washer to the pressure sensing pipe is gold-plated. A pressure sensor characterized in that the insertion port into which the pressure-conducting pipe is inserted in the gold-plated through hole is sealed with a sealing material.

2. In the pressure detection method described in claim 1, The through hole of the washer is a first hole into which the tip end of the other end of the pressure-sensing pipe is inserted, A pressure sensor characterized by being formed by a second hole having a larger diameter than the first hole.

3. A pressure measuring device comprising a pressure sensor according to claim 1 or claim 2, A body having a pressure-receiving chamber that receives the pressure of the fluid to be measured, and a sensor connection port that communicates with the pressure-receiving chamber via a pressure-sensing path, A circuit board holder attached to the aforementioned body, The pressure sensor's sensor case is mounted on a circuit board that is positioned upright on the circuit board holder adjacent to the sensor connection port, The substrate holder has a hole formed at a position corresponding to the sensor connection port through which the washer can be inserted, and a groove extending from the hole to the substrate. The pressure sensing pipe of the pressure sensor is inserted into the groove, and the washer is welded to the sensor connection port with the washer inserted into the hole. The pressure measuring device is characterized in that the sealing material is filled in the area from the washer through the hole and groove to the substrate.

4. The steps include forming a body through which a sensor connection port is opened, which is connected to a pressure-receiving chamber that receives the pressure of the fluid to be measured, The steps include: inserting a pressure-sensing pipe through the through-hole of a washer connected to the sensor connection port and welding it to form a welded body; The steps include applying gold plating to the welded body, The steps include: soldering the end of the gold-plated pressure-sensing pipe opposite to the washer through the sensor case; The steps include:

1. Housing a pressure detection sensor chip inside the aforementioned sensor case to form a pressure sensor; The steps include welding the washer to the sensor connection port, A method for manufacturing a pressure measuring device, characterized by comprising the step of sealing the insertion opening of the through hole into which the pressure sensing pipe is inserted with a sealing material.

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