Pressure sensor

Abstract

The invention provides a pressure sensor capable of suppressing the influence of mechanical stress accompanying temperature change. A pressure sensor unit (10) is provided with a pressure sensor chip (11) connected to an external device (A), and is provided with: a circuit board (50) interposed between the external device and a sensor; a relay connection terminal (36) that is conductively connected to the sensor and the circuit board; a relay connection terminal (37) that is conductively connected to the circuit board and an external device; and a terminal block (24) that positions and supports the connection member and the terminal member, holds the circuit board that overlaps the connection member and the terminal member, and has a cutout (58) of an inner wall portion (55) that adjusts the relative positional relationship of the connection member with respect to the circuit board.

Description

Technical Field

[0001] The present invention relates to a pressure sensor having a simple structure that can be assembled easily and with high reliability. Background Art

[0002] Various sensors for detecting pressure, temperature, etc. are fixed near a measurement object and send detection signals to a measurement device, etc., and are widely used in a form of being built in or external to the measurement device (see Patent Document 1).

[0003] Such various sensors are assembled in a sensor unit that can be installed to be exposed to the same environment as the measurement object. The sensor unit has a terminal block that holds terminals that are electrically connected to the installed sensor. A measurement device is connected to the terminals to utilize the detection signal of the sensor.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2014-98685 Summary of the invention

[0007] Problems to be solved by the invention

[0008] Such various sensors are exposed to the external environment, and therefore, changes in the temperature of the surrounding environment, operation and stop of the installed equipment, changes in the temperature of the fluid flowing through the pipe, etc. may repeatedly act on the sensor unit.

[0009] For example, Fig.18 As shown in (a), in the case of a sensor unit 10 having a circuit substrate 50 for adjusting various electrical signals, etc., provided in front of the sensor 11, as shown in Fig.18 As shown by the black and white arrows in (b), mechanical stress is repeatedly applied to the joint obtained by welding the circuit substrate 50 and the terminal pieces 36d and 37d and the difference in linear expansion coefficient of the terminal block 24. If such stress acts for a long time, the quality of the joint may be reduced, such as cracks in the welding part and peeling of the wiring pattern of the welding part. In addition, for Fig.18 In order to facilitate understanding, the same reference numerals are used for the components of the illustrated pressure sensor 100 that are common to the embodiments described below.

[0010] Therefore, an object of the present invention is to realize a sensor unit that can suppress the influence of mechanical stress caused by the difference in linear expansion coefficient of internal parts of the pressure sensor accompanying the temperature change of the surrounding or fluid and can perform assembly operations, and to provide a pressure sensor having the sensor unit and a manufacturing method of the sensor unit.

[0011] Solutions to Solve Problems

[0012] One way of inventing a sensor unit for solving the above-mentioned problems is a pressure sensor, which is composed of a sensor unit having a sensor connected to an external device, and is characterized in that it comprises: a circuit substrate, which is configured to be interposed between the external device and connected to the sensor; a connecting component located between the sensor and the circuit substrate and conductively connected to the sensor and the circuit substrate, and one or both of a terminal component that is conductively connected to the circuit substrate and is used to conductively connect the circuit substrate to the external device; and a terminal seat, which fixes and positions one or both of the connecting component and the terminal component, and the circuit substrate is placed on one or both of the connecting component and the terminal component, and the pressure sensor has an adjustment portion, which adjusts the relative position relationship of at least one of the connecting component, the terminal component and the terminal seat with respect to the circuit substrate.

[0013] Effects of the Invention

[0014] Thus, according to one embodiment of the present invention, the relative positional relationship of at least one of the connecting component, the terminal component and the terminal seat with respect to the circuit substrate can be adjusted by the adjustment unit. Therefore, even if a phenomenon such as mechanical stress in a planar direction is applied to the circuit substrate, the load of the mechanical stress can be absorbed by adjusting the relative positional relationship of the circuit substrate, thereby preventing damage and the like from occurring.

[0015] Therefore, a sensor unit having a simple structure capable of suppressing the influence of mechanical stress caused by the difference in linear expansion coefficient of internal components of the pressure sensor accompanying the temperature change of the surroundings or the fluid and capable of performing assembly work can be realized, and a pressure sensor including the sensor unit can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 1 is a diagram showing a pressure sensor including a pressure sensor unit as an example of a sensor unit according to an embodiment of the present invention, and is a longitudinal sectional view showing a schematic overall structure thereof.

[0017] Figure 2 The figures show an outline of the manufacturing method of the pressure sensor, (a) is an exploded perspective view of each component separated from the stacking direction and viewed from above, and (b) is a perspective view of one component viewed from below.

[0018] Figure 3 It is a three-dimensional diagram showing its main parts as viewed from one direction.

[0019] Figure 4Is installed in Figure 3 The figure shows a connecting terminal of a main part of a device, (a) is its elevational main view, (b) is its top view, (c) is its bottom view, and (d) is a top view of a lead frame representing the three parts.

[0020] Figure 5 Is installed in Figure 3 The main parts of the Figure 4 Figures of different connection terminals, (a) is its elevational front view, (b) is its top view, (c) is its bottom view, and (d) is its side view.

[0021] Figure 6 It indicates the connection terminal direction Figure 3 The figure shows the installation status of the main parts of the vehicle, (a) is its longitudinal sectional view, and (b) is its top view.

[0022] Figure 7 Yes Description Figure 6 , (a) is a stereoscopic view of one connecting terminal viewed from one direction and a stereoscopic view of other connecting terminals viewed from different directions, and (b) is a top view of the two connecting terminals.

[0023] Figure 8 It indicates the connection terminal and circuit board Figure 3 The figures show the installation status of the main parts of the circuit board, (a) is a longitudinal sectional view thereof, (b) is a stereoscopic view thereof, and (c) is an enlarged stereoscopic view of the connection portion between the circuit board and the connection terminal.

[0024] Fig. 9 Yes Description Figure 8 4 and 5. The figures show the connection state of the connection parts in the figure, (a) is a longitudinal sectional view showing the effect of the structure, and (b) is a longitudinal sectional view showing the case where the structure is not adopted.

[0025] Fig.10 The figures illustrate the effects of the present embodiment, (a) is an enlarged longitudinal sectional view when there is no load of mechanical stress, (b) is an enlarged longitudinal sectional view when there is a load pushing toward the circuit substrate side, and (c) is an enlarged longitudinal sectional view when there is a load pulled by the circuit substrate.

[0026] Fig.11 It is a diagram showing a first other mode of the present embodiment and is a partially enlarged longitudinal sectional view thereof.

[0027] Fig.12 The figures are diagrams showing a second other mode of the present embodiment, (a) is a partially enlarged longitudinal sectional view showing one mode, (b) is a partially enlarged longitudinal sectional view showing a mode different from (a), and (c) is a partially enlarged longitudinal sectional view showing a mode different from (a) and (b).

[0028] Fig.13 is a diagram showing a second further embodiment of the present embodiment, (a) to (d) are diagrams including Fig.12 (a)~ Fig.12 (c) shows different partial enlarged longitudinal sectional views.

[0029] Fig.14 It is a diagram showing a third other form of the present embodiment and is a partially enlarged longitudinal sectional view thereof.

[0030] Fig.15 It is a diagram showing a fourth other form of the present embodiment and is a partially enlarged longitudinal sectional view thereof.

[0031] Fig.16 It is a diagram showing a fifth other form of the present embodiment and is a longitudinal sectional view schematically showing its overall structure.

[0032] Fig.17 It is a diagram showing a sixth other form of the present embodiment and is a longitudinal sectional view schematically showing its overall structure.

[0033] Fig.18 This is a longitudinal sectional view showing a technique before the present embodiment was conceived.

[0034] Explanation of symbols

[0035] 10—pressure sensor unit, 11—pressure sensor chip, 14a, 14g—covering layer, 20—waterproof housing, 24—terminal seat, 24s—side wall portion, 25—terminal seat cover, 26—sealing material, 26a, 26g—adhesive for fixing terminals, 30—connector component, 36 (36A to 36C, 37 (37A to 37C), 66, 136—relay connection terminal, 36d, 36e, 37d, 37e—terminal piece, 36f—flat portion, 36h, 36he, 36i, 36ie—protruding piece, 37e—bent piece, 37f—connecting surface, 38 —lead, 40—pin, 50—circuit substrate, 50r—corner recess, 50u—recessed wall electrode surface, 51, 53—terminal retaining portion, 53a, 53b—slit, 54—pillar-shaped portion, 55~57—inner wall portion, 55g~57g—groove, 55h—insertion groove, 55s—slit, 58—cut, 65—upper cover, 66a, 66f, 66i, 66q, 66r, 66t—deformation portion, 68—cut, 69—elastic member, 100—pressure sensor, A—external device, LR—liquid seal chamber, M—plating, S—conductive connection material, SR—installation space. DETAILED DESCRIPTION

[0036] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Figures 1 to 10 The diagrams are for explaining a pressure sensor including a pressure sensor unit as an example of a sensor unit according to an embodiment of the present invention and a method for manufacturing the sensor unit.

[0037] exist Figure 1 as well as Figure 2 In the embodiment, the pressure sensor 100 is manufactured as follows: the pressure sensor unit 10 composed of components stacked and assembled as described later is mounted on a target portion for measuring the pressure characteristics of the external environment, and the pressure information detected by the pressure sensor chip 11 is output to the connected external device A. The pressure sensor 100 of this embodiment is configured so that the pressure sensor unit 10 housed in the waterproof housing 20 made of resin can be connected to a pipe for introducing a fluid such as gas or liquid to be detected pressure by a metal joint component 30.

[0038] Here, the waterproof housing 20 is made into a cylindrical shape capable of accommodating the pressure sensor unit 10, and the peripheral edge of the cover 28 of the fixed joint component 30 is connected to the opening 20b on one end side. The joint component 30 is formed with an internal thread 30s in a manner that can 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 the arrow P is introduced into the pressure chamber PR on the downstream side of the cover 28 via a port 30a connected to the internal thread 30s.

[0039] The pressure sensor unit 10 comprises: a housing 12 which is made into a short cylindrical shape and whose axial lower end surface is joined and fixed to a cover 28; a pillar 13 which is provided with a pressure sensor chip 11 and is arranged in a manner located at the center of an inner cylinder of the housing 12; and a sealing glass 14 which fills and seals around the pillar 13 in the inner cylinder of the housing 12 and fixes a component that passes through the inner cylinder.

[0040] 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.

[0041] 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.

[0042] Thus, the pressure sensor chip 11 functions as a pressure sensor that detects pressure fluctuations of the pressure transmission medium in the liquid seal chamber LR as the pressure of the detection target fluid introduced into the pressure chamber PR from the pipe connected to the joint member 30 via the diaphragm 32 .

[0043] Here, the pressure sensor chip 11 is configured to be electrically connected to the pins 40 connected to the plurality of leads 38 from the external device A through the circuit substrate 50 described later via the bonding wires 11w, and to be supplied with power, and to output a detection signal as pressure information. In addition, the pressure transmission medium 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 via the oil filling tube 44. These pins 40 and the oil filling tube 44 are arranged in the same circle at equal intervals with the support 13 as the center, and are supported insulated from the housing 12 via an insulating material such as the sealing glass 14. In addition, the oil filling tube 44 is closed at one end after the pressure transmission medium is filled.

[0044] Here, the diaphragm 32 is fixed to the lower end surface of the housing 12 by a diaphragm protection cover 34 having a plurality of communication holes 34a, thereby preventing damage due to external force or sudden pressure in the pressure chamber PR. In addition, a concave frame 16 is fixed to one end side of the sealing glass 14 and a cover-shaped shielding plate 17 is installed. The frame 16 receives the pressure transmission medium 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.

[0045] The pins 40 are arranged on the bottom portion 24b of the resin terminal block 24 formed in a short-sized cylindrical shape with a bottom, and two power supply terminals, one output signal terminal, and five adjustment terminals used in assembly are arranged, and are electrically connected to the pressure sensor chip 11 via bonding wires 11w. These pins 40 are inserted into the insertion holes 24h formed in the bottom portion 24b of the terminal block 24, and are fixedly supported by the sealing glass 14. Here, a part of the substantially cylindrical side wall portion 24s of the terminal block 24 is formed in a flat shape, and the terminal holding portions 51 and 53 for mounting and holding the relay connection terminals 36 (36A to 36C) and 37 (37A to 37C) described later are arranged at symmetrical positions in the center of the cylinder. The terminal block 24 is bonded to the upper end surface of the housing 12 by a silicon-based adhesive. In addition, a cover layer 14a made of a silicon-based adhesive is formed with a predetermined thickness on the entire upper end surface of the sealing glass 14 where the pins 40 protrude. Alternatively, the cover layer may be an adhesive such as epoxy resin.

[0046] The two ends of the pin 40 penetrate the two sides of the sealing glass 14 in the inner tube of the housing 12, and the pressure sensor chip 11 is conductively connected to the one end side of the liquid seal chamber LR side via the bonding wire 11w. In addition, the terminal piece 36e of the relay connection terminal 36 held by the side wall portion 24s of the terminal seat 24 is spot welded (or molten metal welding) to the other end side of the power supply terminal and the output signal terminal among the plurality of pins 40, and is conductively connected to the end surface. In addition, the relay connection terminal 37 connected to the lead 38 from the external device A is held on the opposite (opposite) side of the relay connection terminal 36 of the side wall portion 24s of the terminal seat 24 as described later. The circuit substrate 50 placed in a mounted manner is connected to the terminal pieces 36d and 37d of these relay connection terminals 36 and 37 by soldering with molten solder (conductive connection material) S applied. That is, the relay connection terminal 36 constitutes a connection component, and the relay connection terminal 37 constitutes a terminal component. Furthermore, as the conductive connection material, not only molten metal such as solder S but also, for example, an adhesive containing a conductive material may be applied.

[0047] Here, the circuit substrate 50 is interposed between the pressure sensor chip 11 and the external device A and functions as a part of the circuit structure. In this embodiment, a conversion adjustment circuit is mounted to adjust the different input and output voltages of the pressure sensor chip 11 and the external device A, for example, to make the input voltage DC12V, DC3.3V of the external device A become the input and output voltage DC5V of the operating voltage of the pressure sensor chip 11. This conversion adjustment circuit is not limited to this embodiment, and is an arbitrary conversion adjustment circuit for dealing with various drive voltages and pressure detection signal signal forms such as voltage output forms of the output voltage, two-wire / three-wire current output forms, or digital output forms that are different from this embodiment. In addition, these conversion adjustment circuits are composed of a plurality of electronic components not shown in the figure.

[0048] Here, the terminal block 24 is provided with a terminal block cover 25 on the opening side of the cylindrical side wall portion 24s, and the installation space SR of the pin 40, the terminal pieces 36d, 36e, 37d of the relay connection terminals 36, 37, and the circuit substrate 50 is closed, and the pressure sensor unit 10 is constructed together with the housing 12 to which the pillar 13 of the pressure sensor chip 11 is fixed by the sealing glass 14. In the pressure sensor unit 10, the outer peripheral edge of the housing 12 and the cover 28 connected to the joint member 30 are welded from the outside by TIG welding, plasma welding, laser welding, etc., and integrated with a desired bonding strength. The pressure sensor unit 10 is installed in the waterproof housing 20, and is waterproofed and fixed by filling the sealing material 26 such as polyurethane resin. Here, the terminal block 24 and the terminal block cover 25 close the installation space SR, and an air layer with low thermal conductivity can be formed around the circuit substrate 50, which can prevent the temperature change from the surrounding of the pressure sensor and the piping from being rapidly transmitted to the circuit substrate 50. In addition, the circuit substrate 50 itself, the mounted parts mounted on the circuit substrate 50, or the connection parts between the circuit substrate 50 and the relay connection terminals 36, 37 are not in contact with the sealing material 26, thereby preventing mechanical stress caused by contraction and expansion of the sealing material 26 due to changes in ambient temperature from acting on the connecting components, mounting parts, and especially their soldered parts.

[0049] The pressure sensor unit 10 is assembled in a stacked order by placing the terminal block 24, the circuit board 50, and the terminal block cover 25 from the housing 12 fixed to the cover 28 connected to the joint member 30. After the relay connection terminals 36 and 37 are placed on the terminal holding portions 51 and 53 of the side wall portion 24s, the terminal block 24 is placed on the housing 12 and the end of the pin 40 is spot welded to the terminal piece 36e of the relay connection terminal 36. After that, the circuit board 50 is placed on the terminal pieces 36d and 37d of the relay connection terminals 36 and 37 and soldered to conduct the connection. Here, it is not limited to spot welding, and of course, the terminal piece 36e of the relay connection terminal 36 and the end face of the pin 40 can be connected to each other by soldering, riveting, etc. In addition, the bottom surface portion 24b of the terminal block 24 is opened with a through hole that can be appropriately assembled, for example, a through hole 24H (not shown) for the oil filling tube 44 is also opened.

[0050] In detail, Figure 3 to Figure 7 As shown, the terminal block 24 has the relay connection terminals 36 and 37 mounted and held in the terminal holding portions 51 and 53 formed on the side wall portion 24 s.

[0051] The relay connection terminal 36 is formed in a shape in which the end pieces (terminal pieces) at one end and the other end of the two ends are facing each other, so that the flat surface 36f between the terminal pieces 36d and 36e at the two ends extending in the parallel direction of the U-shape is arranged in a parallel posture relative to the outer surface of the terminal holding portion 51 of the terminal seat 24, and the terminal pieces 36d and 36e are extended into the side wall portion 24s. The relay connection terminal 37 is also formed in a U-shape: the terminal piece 37d is extended in the side wall portion 24s of the terminal seat 24, and the flat connection surface 37f is parallel to the outer surface of the terminal holding portion 53, and a bent piece 37e is provided to bend the opposite side of the terminal piece 37d. The core wire C of the lead 38 from the external device A is soldered to the connection surface 37 f of the relay connection terminal 37 , thereby electrically connecting the pressure sensor chip 11 to the external device A via the pins 40 , the relay connection terminals 36 , 37 , and the circuit board 50 .

[0052] The terminal holding portion 51 is formed with a plurality of inner wall portions 55 on the inner side of the side wall portion 24s of the terminal seat 24, which are opposed to each other via a groove 55g, which is a fixing groove for fixing the relay connection terminal 36, and the upper surface of each of the inner wall portions 55 is formed to be at the same height. Similarly, the terminal holding portion 53 is formed with an inner wall portion 56 on the inner side of the side wall portion 24s of the terminal seat 24, which is opposed to each other via a groove 56g, which is a fixing groove for fixing the relay connection terminal 37. A pair of inner wall portions 57 are formed between these inner wall portions 55, 56 and on the inner side of the side wall portion 24s, which are opposed to each other via a groove 57g. That is, grooves 55g to 57g are formed continuously between the side wall portion 24s of the terminal seat 24 and the inner wall portions 55 to 57.

[0053] The terminal holding portion 51 inserts and positions each terminal piece 36e of the relay connection terminals 36A to 36C in a state of contacting the bottom surface of three slits 55s between four inner wall portions 55 facing the side wall portion 24s of the terminal seat 24. In this state, the plane portion 36f of the relay connection terminals 36A to 36C formed to be larger than the slit 55s contacts the side facing portion of the inner wall portion 55 on the side of the side wall portion 24s, and the terminal pieces 36d of the three relay connection terminals 36A to 36C are folded back at positions on the same plane in a manner of contacting the upper surface of the inner wall portion 55. The relay connection terminals 36A to 36C are provided with protrusions (fixing portions) 36h and 36i formed by extending the portion of the plane portion 36f adjacent to the terminal piece 36e in the plane direction of the plane portion 36f. In addition, an insertion groove 55h for the protrusions 36h and 36i is formed on the bottom surface of the groove 55g between the side wall portion 24s of the terminal seat 24 and the side wall 55. The protrusions 36h and 36i are inserted into the insertion groove 55h to maintain the relay connection terminals 36A to 36C in an upright state. According to the structure of the terminal retaining portion 51, the terminal piece 36e of the relay connection terminals 36A to 36C can be inserted and assembled in a manner suitable for the groove 55g and the slit 55s from the open end of the terminal seat 24, that is, from the top, and the fixing portion is formed according to such a structure. In addition, the protrusion 36i is Figure 2 The diagram is omitted. Figure 4 Medium picture.

[0054] The relay connection terminal 36 is made into a group of three relay connection terminals 36A to 36C of different shapes, and the terminal pieces 36d and 36e are bent at right angles to the flat surface portion 36f, respectively. The terminal piece 36e is formed in a parallel state with a narrower interval than the terminal piece 36d and is extended in a direction parallel to the bottom surface portion 24b of the terminal seat 24. In detail, the relay connection terminal 36 is formed in a shape that is extended in parallel with narrow intervals near the center because the terminal piece 36e is connected to the pins 40 that are arranged at equal intervals in the same circle with the support 13 as the center corresponding to the small pressure sensor chip 11. In addition, the terminal piece 36d can be connected to the circuit substrate 50 at any interval, so it is formed in a shape that is arranged and extended at a wider interval than the terminal piece 36e in order to facilitate the connection operation. In addition, as Figure 4As shown in (d), the relay connection terminal 36 is formed by punching out three relay connection terminals 36A to 36C in a group in an integrated state with a lead frame 36LF, and then bending the terminal pieces 36d and 36e relative to the flat portion 36f, the protruding pieces 36h and 36i, respectively. In addition, the slit 55s of the inner wall portion 55 is open from the groove 55g to the bottom surface 24b side of the terminal seat 24, but when the terminal fixing adhesive 26g described later is injected into the groove 55g to fix the relay connection terminal 36, the back side of the flat portion 36f (outside the terminal seat 24) blocks the terminal fixing adhesive 26g, preventing the terminal fixing adhesive 26g from leaking to the bottom surface 24b side of the terminal seat 24.

[0055] The terminal holding portion 53 is formed with slits 53a and 53b on the upper and lower surfaces thereof, into which the terminal piece 37d and the bent piece 37e of the relay connection terminal 37 can be inserted and which penetrate the side wall portion 24s of the terminal seat 24. In addition, on the terminal holding portion 53, the terminal piece 37d and the bent piece (intersection portion) 37e penetrate the slits 53a and 53b of the side wall portion 24s of the terminal seat 24 and pass through the inner groove 56g in the intersecting direction, and are positioned in a state of contact with the upper surface of the inner wall portion 56 and the bottom surface of the groove 56g.

[0056] Due to such a structure, each relay connection terminal 37A to 37C of the relay connection terminal 37 is made into the same shape, and the terminal piece 37d and the bent piece 37e are bent in the same direction orthogonal to the connection surface 37f in a manner that contacts the upper surface and the lower surface of the terminal holding portion 53. The terminal piece 37d is formed in a shape that can be inserted into the side wall portion 24s of the terminal seat 24 from the slit 35a to a degree that the circuit substrate 50 can be placed. In the relay connection terminal 37, the terminal piece 37d and the bent piece 37e are formed in a narrow width relative to the wide connection surface 37f, and the two sides of the terminal piece 37d are formed with a snap-fit ​​piece 37g that is bent in the same direction and hooked in a manner that bites into the upper surface of the terminal holding portion 53. In addition, the snap-fit ​​piece 37g can be omitted when it is sufficient to fix it with the terminal fixing adhesive 26g described later.

[0057] Thus, the relay connection terminal 36 is mounted on the terminal holding portion 51, and can be mounted in a state where the long terminal pieces 36d and 36e are positioned between the inner wall portion 55 (slit 55s) on the inner side of the side wall portion 24s of the terminal seat 24, and the protruding pieces 36h and 36i are inserted into the insertion groove 55h on the bottom surface of the groove 55g between the side wall portion 24s and the inner wall portion 55 to be positioned and held, and can also be mounted in a manner in which the protrusion amount of the terminal piece 36e into the inside of the terminal seat 24 is also constant. According to such a structure, each terminal piece 36d can be positioned and supported at the height of the upper surface of the inner wall portion 55, and the terminal piece 36e can be positioned and supported at the height of the bottom surface of the slit 55s between the inner wall portions 55, and the protrusion amount of the terminal piece 36e into the inside of the terminal seat 24 is also constantly positioned and supported. In this way, the positional relationship of the terminal piece 36e relative to the plane where the pins 40 are arranged, that is, the position of the end face of the pin 40 relative to the extension direction of the terminal piece 36e and the width direction of the terminal piece 36e is stable, and the terminal piece 36e and the end of the pin 40 can be stably positioned in the height direction. This is because it is necessary to make the relative positional relationship between the end face of the pin 40 and the terminal piece 36e constant after spot welding. In addition, the relay connection terminal 37 is installed in the terminal retaining portion 53 so that the terminal piece 37d can be positioned and retained on the upper surface of the inner wall portion 56 on the inner side of the side wall portion 24s of the terminal seat 24. That is, the groove 55g side of the inner wall portion 55 of the terminal seat 24 acts as a support position for the relay connection terminal 36.

[0058] Therefore, with respect to the relay connection terminals 36 and 37, the terminal piece 36e and the bent piece (fixing portion) 37e can pass through the side wall portion 24s of the terminal seat 24 and be located in the grooves 55g and 56g with a depth in the direction of overlapping the circuit substrate 50 formed between the inner wall portions 55 and 56. The relay connection terminals 36 and 37 can be positioned and fixed by injecting the terminal fixing adhesive 26g into the grooves 55g and 56g thereof. The grooves 55g and 56g of the inner wall portions 55 and 56 are continuous with both sides of the groove 57g between the side wall portion 24s and the inner wall portion 57, so that the steps (manufacturing method) of inserting a dispenser into the wide groove 57g thereof and injecting the terminal fixing adhesive 26g can be performed to easily complete the fixing operation (refer to Figure 6). Afterwards, with respect to the relay connection terminals 36 and 37, the terminal piece 36e can be spot welded to the pin 40 in a stable posture and connected, and the circuit substrate 50 placed on the terminal pieces 36d and 37d can be soldered and connected in a stable posture. Here, a plane portion 29 is formed on the inner surface of the arc-shaped side wall portion 24s on the terminal seat 24 and opposite to the inner wall portion 57. This is to allow the plane portion to engage with the protrusion 25a on the lower surface of the terminal seat cover 25, so that when the terminal seat cover 25 is placed on the terminal seat 24, it plays a role in preventing the horizontal displacement and rotation of the terminal seat cover 25. The terminal seat 24 and the terminal seat cover 25 are placed in a close manner, so that when the sealing material 26 is filled around the terminal seat 24 and the terminal seat cover 25, it is possible to prevent the sealing material 26 from leaking into the terminal seat 24.

[0059] These relay connection terminals 36 and 37 are made so that the terminal pieces 36d and 37d or the connection surface 37f to be soldered are plated with M to improve the wettability of the molten solder, thereby reducing the occurrence of poor connection and enabling conductive connection. The adjacent parts of the connection surface 37f of the relay connection terminal 37 are also plated with M to suppress the fall-off of the conductive wire C of the connection wire 38 after soldering. Here, the relay connection terminals 36 and 37 are plated with M only in the areas where soldering is required, and the plating M is not applied to other areas, thereby suppressing the outflow of molten solder. In addition to providing a part that improves the wettability of the solder by plating M as in this example, the soldering surface can also be kept in the state of the metal base surface, and a resist, coating, etc. can be applied to the part that restricts the flow of the solder.

[0060] like Figure 8As shown in FIG. 1 , the outer peripheral end surface of the portion of the circuit substrate 50 corresponding to the terminal pieces 36d and 37d of the relay connection terminals 36 and 37 is formed with a concave wall electrode surface (concave wall surface) 50u of the connection area which is concave in a direction parallel to the plane of the circuit substrate 50, i.e., inwardly in a U-shape and is open on both the front and back sides perpendicular to the plane of the circuit substrate 50 and functions as a connection position. The concave wall electrode surface 50u is concave inwardly by a distance L of a semicircle which allows molten solder to easily penetrate from the outer peripheral end surface of the circuit substrate 50 to the entire (entire surface), and the inner surface is plated with a plating M having excellent solder wettability. That is, the concave wall electrode surface 50u is formed in an elliptical cutout shape with a depth L from the outer peripheral end surface of the circuit substrate 50 toward the inner side of the substrate. By making the inward concave shape of the concave wall surface a semicircular shape, it is expected that the stress inside the concave wall electrode surface 50u formed by the solder fillet acts evenly. The stress becomes equal, which can improve the resistance to the bad situation such as poor conduction caused by the crack of the soldering part caused by the repeated hot and cold applied to the pressure sensor, that is, the so-called thermal cycle, and can complete the connection with high reliability. In addition, in the manufacturing process of the circuit substrate 50, it can also be made using the same processing tools as the processing of the mounting hole of the mounting component and the outer shape processing of the circuit substrate 50. In the case of a rectangular shape, other processes and other tools such as processing using a disc-shaped tool are required, but by making it semicircular, it is advantageous in terms of productivity and quality.

[0061] In contrast, the terminal pieces 36d and 37d of the relay connection terminals 36 and 37 are formed wider than the concave wall electrode surface 50u of the circuit substrate 50 and are formed longer than the depth (distance) L of the concave wall electrode surface 50u from the outer peripheral end surface, so that the circuit substrate 50 can be placed in a stable posture. In addition, the terminal seat 24 has a support-shaped portion 54 formed on the inner surface side of the side wall portion 24s to be embedded in the corner recesses 50r formed at the four corners of the circuit substrate 50, so that the circuit substrate 50 can be positioned. That is, the terminal pieces 36d and 37d of the relay connection terminals 36 and 37 function as a support area near the concave wall electrode surface 50u of the circuit substrate 50. In addition, in the present embodiment, a recessed wall electrode surface 50u is formed in the connection area of ​​the circuit substrate 50 on both sides connected to the terminal pieces 36d and 37d of the relay connection terminals 36 and 37, but this is not limited to this. The recessed wall electrode surface 50u may not be formed and the connection may be made on the outer peripheral end surface of the circuit substrate 50, or the recessed wall electrode surface 50u may be provided only on one side. However, from the perspective of connection operability and reliability, it is preferably formed on both sides.

[0062] Therefore, if Fig. 9 As shown in (a), the circuit board 50 is placed on the terminal pieces 36d and 37d of the relay connection terminals 36 and 37 in a stable posture and is held in a stable posture by the pillar-shaped portion 54 positioned at the terminal base 24, and is used to Fig. 9The semicircular concave wall electrode surface 50u′ shown in (b) has a large capacity and a solder S of a stable shape with sufficient solder leg height, and the concave wall electrode surface 50u is connected to the terminal pieces 36d and 37d with high reliability. The soft soldering part, that is, the connection area, becomes the back side of the circuit substrate 50, so the connection area cannot be directly visually confirmed. However, as in the present embodiment, the state of the solder leg inside the concave wall portion 50u is managed by visual inspection or image recognition, thereby determining whether the soft soldering is performed normally. In addition, a through hole 50H is opened on the circuit substrate 50 for inserting the oil filling tube 44 during assembly.

[0063] Moreover, if Fig.10 As shown in (a), on the terminal holding portion 51, a notch (recess) 58 is formed at the upper portion of the inner wall portion 55 on the side opposite to the side wall portion 24s of the terminal seat 24 and at a position higher than the terminal fixing adhesive 26g injected and cured in the groove 56g (see Figure 1 , Figure 3 , Figure 6 ), in this embodiment, the height of the terminal fixing adhesive 26g is suppressed and a cutout 58 of a required sufficient size is formed. Thus, in the terminal holding portion 51, even if the installation space SR for the pins 40, the relay connection terminals 36, 37, and the circuit substrate 50 is sandwiched, indirect heat conduction via the terminal seat 24 and the like occurs, but a portion of the relay connection terminal 36 facing the cutout 58 of the inner wall portion 55 is allowed to function as a deformation portion and deform.

[0064] Specifically, even if there is a difference in the amount of expansion and contraction between the terminal base 24 and the circuit substrate 50 due to a temperature change due to a difference in the linear expansion coefficients of the terminal base 24 and the circuit substrate 50, as shown in FIG. Fig.10 (b) and Fig.10 As shown in (c), a part (deformation part) of the relay connection terminal 36 can be elastically deformed so that the relay connection terminal 36 can be reset relative to the inner wall portion 55 in a direction that allows the relay connection terminal 36 to swing and expand in a direction parallel to the bottom surface portion 24b of the circuit substrate 50 and the terminal block 24, in other words, in a direction that leaves or enters the cutout 58. Therefore, the cutout 58 of the inner wall portion 55 can function as an adjustment portion to prevent mechanical stress from being applied to the joint portion of the solder S that connects the terminal pieces 36d and 37d of the relay connection terminals 36 and 37 to the circuit substrate 50, thereby preventing the cracks in the soldered portion and the peeling of the circuit pattern around the concave wall portion 50u of the circuit substrate 50 from causing poor conduction and other reductions in the joint quality.

[0065] Thus, in the pressure sensor unit 10 of the pressure sensor 100 of the present embodiment, the relay connection terminal 36 can utilize the cutout 58 of the inner wall portion 55 to elastically deform at the separation interval from the groove 55g side of the inner wall portion 55 in the terminal seat 24 to the recessed wall electrode surface 50u of the circuit substrate 50. Even if mechanical stress is generated between the joint between the relay connection terminal 36 and the solder S of the substrate circuit 50 due to the difference in linear expansion coefficients between the terminal seat 24 and the circuit substrate 50 caused by changes in ambient temperature, the relay connection terminal 36 is a structure that allows expansion and contraction in the direction of approaching and separating from the substrate circuit 50, thereby preventing excessive stress from acting between the joints.

[0066] Therefore, a pressure sensor 100 equipped with a pressure sensor unit 10 can be provided, which can suppress the influence of the difference in linear expansion coefficient between the circuit substrate 50 and the terminal seat 24 on the mechanical stress at the joint between the relay connection terminal 36 and the solder S of the substrate circuit 50 by using a simple structure that only forms a cutout 58 on the groove 55g side of the inner wall portion 55 of the terminal seat 24, and can perform assembly operations.

[0067] However, as mentioned above Fig.18 As shown, when the terminal holding parts 51 and 53 formed on the side wall part 24s of the terminal block 24 are in a manner of inserting the relay connection terminals 136 and 37 formed in a U-shape from the outer surface side, the terminal block 24 is laid down horizontally at least twice to inject the terminal fixing adhesive 26a into the groove opened at the lower side of the terminal holding parts 51 and 53 of the side wall part 24s. In contrast, in the present embodiment, the formation of the terminal fixing adhesive 26g can be completed simply and quickly by a single injection operation while the terminal block 24 is kept in an upright state, and the positioning accuracy of the relay connection terminals 36 and 37 can be prevented from being reduced when facing horizontally.

[0068] Here, as a first other mode of this embodiment, Fig.11 As shown, the protrusions 36he and 36ie formed by extending the protrusions 36h and 36i of the relay connection terminal 36 provided in the terminal holding portion 51 may be deeply inserted into the bottom of the groove 55g of the terminal seat 24 to perform positioning and fixing. As a result, in the terminal holding portion 51, the terminal fixing adhesive 26g for injecting into the groove 55g of the terminal seat 24 and curing to fix the relay connection terminal 36 can be omitted. In addition, instead of the terminal fixing adhesive 26g, the position of the concave portion that fixes the terminal seat 24 to the cover layer 14a of the sealing glass 14 is moved below the groove 55g and the cover layer 14g is injected and cured, so that the relay connection terminal 36 can also be positioned and fixed together with the terminal seat 24 itself.

[0069] As a second other method of this embodiment, Fig.18 As shown, the relay connection terminal 136 inserted from the outer surface side of the terminal base 24 and provided in the terminal holding portion 51 may be replaced by Fig.12 As shown, a relay connection terminal 66 having a deformed portion described later that can be extended or contracted in the separation direction to adjust the separation interval from the concave wall electrode surface 50u of the circuit substrate 50 is provided on the flat portion 36f side of the terminal piece 36d. Thus, since the deformed portion of the relay connection terminal 66 is deformed in accordance with the mechanical stress between the terminal holding portion 51 and the circuit substrate 50, the same effect as the swing of the relay connection terminal 36 based on the cutout 58 of the inner wall portion 55 of the present embodiment can be obtained, and it is possible to avoid the application of mechanical stress to the joint portion of the solder S that conducts the connection between the terminal pieces 36d and 37d of the relay connection terminals 36 and 37 and the circuit substrate 50, thereby preventing the quality of the joint from being reduced.

[0070] Specifically, for example, a flat surface 36f of the terminal piece 36d may be formed. Fig.12 The cross-sectional waveform deformation portion 66r shown in (a) is formed Fig.12 The cross-sectional curved deformation portion 66f shown in (b) can easily adjust the separation interval. Fig.12 As shown in (c), the separation interval can be easily adjusted by replacing the relay connection terminal 66 with a height (length in the cylindrical axis direction of the terminal block 24) of the flat portion 36f side of the terminal piece 36d and the concave wall electrode surface 50u side of the circuit substrate 50 from the bottom portion 24b of the terminal block 24. That is, Fig.12 The relay connection terminal 66 shown in (c) is capable of adjusting the separation distance between the concave wall electrode surface 50u side of the circuit substrate 50 offset in the cylindrical axis direction of the terminal seat 24 (the intersecting direction relative to the planar direction of the circuit substrate 50) and the groove 55g side of the inner wall portion 55 of the terminal seat 24.

[0071] As the second alternative embodiment, the relay connection terminal 66 may be replaced by Fig.13 The shape shown in the figure may also form a deformed portion 66q ( Fig.13 (a)), or forming a flat plate-shaped deformation portion 66s ( Fig.13 (b)), similarly, a flat plate-shaped deformation portion 66i ( Fig.13 (c)), similarly, a flat plate-shaped deformation portion 66t ( Fig.13 (d)), the separation distance from the concave wall electrode surface 50u of the circuit substrate 50 can be adjusted.

[0072] Here, these relay connection terminals 66 can of course be adapted to be inserted from the outer surface side of the terminal base 24. Fig.18 The terminal holding portion 53 shown in the figure positions and fixes the relay connection terminal 37 provided therein by means of the terminal fixing adhesive 26 a.

[0073] As a third other aspect of this embodiment, it is also possible to replace Fig.18 The relay connection terminal 136 is inserted from the outer surface side of the terminal block 24 and fixed by the terminal fixing adhesive 26a, and the terminal block cover 25 is installed on the upper part of the opening side of the terminal block 24 having the terminal holding portion 53. Fig.14 The upper cover 65 shown in the figure is provided with a notch 68 formed on the outer surface side of the terminal holding portion 51. Specifically, the upper cover 65 covers at least the upper surface of the housing 12 from the outer peripheral side of the terminal seat 24, thereby preventing the sealing material 26 filled in the waterproof housing 20 from directly contacting the terminal seat 24 and the relay terminal connection terminal 136. Fig.10 (a) Fig.10 As shown in (b), the relay connection terminal 136 can swing in the radial direction of the terminal seat 24 to expand and contract (swing in the direction away from the cutout 68 is ensured in the space ensured by the upper cover 65 (deformation adjustment)). In addition, the cutout 68 on the outer surface side of the terminal retaining portion 51 can allow the relay connection terminal 136 to swing greatly in the radial direction of the terminal seat 24. Therefore, in this third other mode, similar to the swinging of the relay connection terminal 36 using the cutout 58 of the inner wall portion 55 in the present embodiment, the portion (deformation portion) of the relay connection terminal 136 corresponding to the cutout 68 can be easily deformed and swung, which can avoid applying mechanical stress to the joint portion of the solder S that connects the terminal pieces 36d, 37d of the relay connection terminals 136, 37 to the circuit substrate 50 and reducing the joint quality.

[0074] Here, the cutout 68 of the terminal holding portion 51 can of course also be applied together with the upper cover 65. Fig.18 In the terminal holding portion 53 shown, the relay connection terminal 37 provided in the terminal holding portion 53 operates in the same manner as the relay connection terminal 136 .

[0075] As a fourth other aspect of this embodiment, it is also possible to cut out Fig.18 The elastic member 69 provided on the upper side of the outer surface of the terminal holding portion 51 shown in the figure covers and holds the relay connection terminal 136, thereby allowing the relay connection terminal 136 to utilize the elastic deformation of the elastic member 69 to make the holding portion (deformation portion) swing greatly in the radial direction of the terminal base 24 (the adjustment direction of the above-mentioned separation interval) ( Fig.15Thus, similar to the swing of the relay connection terminal 36 obtained by the cutout 58 of the inner wall portion 55 in the present embodiment, it is possible to avoid applying mechanical stress to the joint portion of the solder S that conducts the connection between the terminal pieces 36d and 37d of the relay connection terminals 136 and 37 and the circuit substrate 50, thereby preventing the quality of the joint from being reduced.

[0076] Here, the elastic member 69 of the terminal holding portion 51 can of course also be applied to Fig.18 In the terminal holding portion 53 shown, the relay connection terminal 37 provided in the terminal holding portion 53 operates in the same manner as the relay connection terminal 136 .

[0077] Although not shown in the figure, it is of course possible to interchange the structures of the terminal holding portions 51 and 53 and the relay connection terminals 36 and 37 of the present embodiment, or to unify and share one of the structures.

[0078] For example, as a fifth other embodiment of this embodiment, Fig.16 As shown, instead of using the relay connection terminal 37 of the terminal component, the lead wire 38 may be used as a terminal component to penetrate the terminal block 25 and be connected to the circuit substrate 50 by direct soldering or the like. In this fifth other mode, by omitting the relay connection terminal 37 and releasing the support fixation, the circuit substrate 50 can be slidably held together with the deformation of the lead wire 38, and the relative positional relationship with the terminal block 24 can be adjusted. In addition, in this fifth other mode, the lead wire 38 is connected to the circuit substrate 50 in advance, the terminal piece 36e of the relay connection terminal 36 is spot welded to the pin 40, and then the circuit substrate 50 connected with the lead wire 38 is placed on the terminal piece 36d of the relay connection terminal 36, and the placing part is soldered to assemble and manufacture in a manner of covering the terminal block cover 25. In addition, after this assembly operation, the sealing material 26 is filled between the waterproof housing 20 and the terminal block 24 and the terminal block cover 25.

[0079] In addition, as a sixth other embodiment of this embodiment, Fig.17 As shown, the relay connection terminal 37 may be kept as it is (the same adjustment function as the relay connection terminal 36 may be added) and the relay connection terminal 36 as a connection component may not be used, but the pin 40 may be used as a connection component to be conductively connected to the circuit substrate 50 by direct welding or the like. In this sixth other embodiment, the relay connection terminal 36 is omitted to release the support and fixation, the circuit substrate 50 can be slidably held, and the relative position relationship with the terminal block 24 can be adjusted.

[0080] 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 desired combinations of all disclosed specific features.

Claims

1. A pressure sensor, comprising a sensor unit having a sensor connected to an external device, characterized in that: have: a circuit substrate, configured to be interposed between the external device and connected to the sensor; One or both of a connecting member located between the sensor and the circuit substrate and conductively connected to the sensor and the circuit substrate, and a terminal member conductively connected to the circuit substrate for conductively connecting the circuit substrate to the external device; and a terminal seat, which fixes and positions one or both of the connection component and the terminal component, The circuit substrate is mounted on one or both of the connecting member and the terminal member. The pressure sensor includes an adjustment unit that adjusts a relative positional relationship of at least one of the connection member, the terminal member, and the terminal base with respect to the circuit substrate.

2. The pressure sensor according to claim 1, characterized in that: have: The adjustment portion adjusts a separation distance between a support position of one or both of the connection component and the terminal component on the terminal base and a connection position of one or both of the connection component and the terminal component to the circuit substrate.

3. The pressure sensor according to claim 2, characterized in that: The adjusting portion includes a deforming portion at the supporting position that deforms at least a portion of one or both of the connecting member and the terminal member in a separating direction relative to the connecting position so as to adjust the separation interval.

4. The pressure sensor according to claim 3, characterized in that: The adjusting portion has a space in which the deforming portion that adjusts the separation interval with respect to the connection position can be deformed.

5. The pressure sensor according to claim 3, characterized in that: The adjustment portion has a recessed portion formed at the support position in the terminal block, and can deform the deformable portion in a direction away from the recessed portion or in a direction entering the recessed portion.

6. The pressure sensor according to claim 5, characterized in that: The adjustment portion covers the terminal base with a member that forms a space that allows the deformation portion to deform in a direction away from the recessed portion.

7. The pressure sensor according to claim 3, characterized in that: The adjusting portion includes an elastic member that positions and holds the deforming portion at the supporting position, and the elastic member is elastically deformable so as to allow the deforming portion to deform in a direction for adjusting a separation interval between the supporting position and the connecting position.

8. The pressure sensor according to claim 3, characterized in that: The deformation portion is deformed between the supporting position and the connecting position so as to extend or contract in a separation direction between the supporting position and the connecting position.

9. The pressure sensor according to claim 8, characterized in that: The cross-sectional shape of the deformation portion in the separation direction between the support position and the connection position is formed in a corrugated shape.

10. The pressure sensor according to claim 8, characterized in that: The cross-sectional shape of the deformation portion in the separation direction between the support position and the connection position is formed into a curved shape.

11. The pressure sensor according to claim 8, characterized in that: The deformed portion is formed in a plate shape in which at least a portion between the supporting position and the connecting position has a width narrower than that on the connecting position side.

12. The pressure sensor according to claim 8, characterized in that: The deformable portion is located between the support position and the connection position offset in a direction intersecting the planar direction of the circuit substrate, and deforms so as to adjust a separation distance between the support position and the connection position in the planar direction of the circuit substrate.

13. The pressure sensor according to claim 1, characterized in that: The adjustment portion is configured so that the holding position of the circuit substrate relative to the terminal block can be slidable, thereby adjusting the relative positional relationship of the terminal block with respect to the circuit substrate.

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