Pressure sensor and method for manufacturing pressure sensor

Abstract

The present invention realizes a pressure sensor having a simple structure and capable of easily and reliably electrically connecting a sensor and a circuit board and facilitating assembly work. A pressure sensor configured from a pressure sensor unit (10) provided with a pressure sensor chip (11) connected to an external device (A), the pressure sensor being provided with: a circuit board (50) interposed between the external device and the sensor; a relay connection terminal (36) that is conductively connected to the sensor and the circuit board; and a relay connection terminal (37) that is conductively connected to the circuit board and the external device. Concave wall electrode surfaces (50u) connected to the two sets of relay connection terminals are formed on the outer peripheral end surface of the circuit board, and the two sets of relay connection terminals are provided with terminal pieces (36d, 37d) which can stably carry the circuit board and are larger than the opening shape of the concave wall electrode surfaces. The present invention is configured so as to be able to perform a connection operation of soldering on a concave wall electrode surface such that a circuit board is placed on terminal pieces of two sets of relay connection terminals.

Description

Technical Field

[0001] The present invention relates to a pressure sensor with a simple structure that can be assembled easily and with high reliability, and a method for manufacturing the pressure sensor. 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 used by being assembled in a sensor unit that can be exposed to the same environment as the measurement object. Not only is the sensor directly connected to the measurement device, but also the electrical characteristics of one or both of the sensor and the external device may need to be changed.

[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] However, in such a sensor unit, for example, when the specifications of the driving voltage from the external control device to the sensor and the output signal from the sensor to the external control device are different, it is not only time-consuming and costly to change the design of the sensor, but it is also effective to make adjustments by sandwiching a conversion circuit substrate for the driving voltage and output signal between the sensor.

[0009] In such a case, a sensor unit having a circuit structure in which a circuit substrate for converting input and output signals is assembled between the sensor and an external device is also worth considering. It is preferable to perform various operations such as positioning the circuit substrate electrically connected to the sensor at a specified position in the sensor unit and conducting the connection, so that various detection signals can be obtained with high reliability.

[0010] Therefore, an object of the present invention is to realize a sensor unit with a simple structure that can easily and reliably conduct and connect a sensor to a circuit board, and to provide a pressure sensor having the sensor unit and a method for manufacturing the pressure sensor.

[0011] Solutions to Solve Problems

[0012] One embodiment of the invention of a pressure sensor that solves the above-mentioned problem is a pressure sensor, which is composed of a sensor unit having a sensor connected to an external device, and comprises: a circuit substrate, which is configured to be interposed between the external device and connected to the sensor; and one or both of a connecting component located between the sensor and the circuit substrate and conductively connected to the sensor and the circuit substrate, and a terminal component conductively connected to the circuit substrate for conductively connecting the circuit substrate to the external device, wherein the connecting component and one or both of the terminal components form a connecting area connected to the circuit substrate, and the connecting area has a supporting area of ​​a size capable of carrying the circuit substrate, and the connecting area of ​​the circuit substrate is located on the supporting area in a manner of being carried on one or both of the connecting component and the terminal component, and is configured to be a structure capable of performing conductive connection operations between the connecting area of ​​the circuit substrate and the connecting areas of the connecting component and one or both of the terminal components.

[0013] Effects of the Invention

[0014] Thus, according to one embodiment of the present invention, a sensor unit having a simple structure that conducts and connects a sensor and a circuit board with high reliability can be realized, and a pressure sensor using the sensor unit and a manufacturing method that facilitates assembly work can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] 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.

[0016] Figure 2 The diagram schematically shows a method for manufacturing the pressure sensor, and is an exploded perspective view of each component separated in the stacking direction.

[0017] Figure 3 It is a three-dimensional diagram showing its main parts as viewed from one direction.

[0018] Figure 4 It means Figure 3 A perspective view of the same major component parts viewed from one direction opposite to the other.

[0019] Figure 5 Is installed in Figure 3 as well as Figure 4 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 6Is installed in Figure 3 as well as Figure 4 The main parts of the Figure 5 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 7 It indicates the direction of the connection terminal and the circuit board. Figure 3 as well as Figure 4 The figures show the installation status of the main parts of the device, (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 substrate and the connection terminal.

[0022] Figure 8 Yes Description Figure 7 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.

[0023] Fig. 9 The figures are diagrams showing a first other mode of the present embodiment, (a) is a partially enlarged longitudinal sectional view illustrating a problem that may arise in the present embodiment, (b) is a partially enlarged longitudinal sectional view showing a solution mode of the problem, and (c) is a partially enlarged longitudinal sectional view showing a solution mode different from (b).

[0024] Fig.10 1 and 2 are views showing a second other mode of the present embodiment, wherein (a) is a partially enlarged longitudinal sectional view showing a solution mode of a problem that may arise in the present embodiment, and (b) is a partially enlarged longitudinal sectional view explaining the problem solved in (a).

[0025] Fig.11 It is a diagram showing a third other form of the present embodiment and is a longitudinal sectional view schematically showing its overall structure.

[0026] Fig.12 It is a diagram showing a fourth other form of the present embodiment and is a longitudinal sectional view schematically showing its overall structure.

[0027] Fig.13 This is a longitudinal sectional view showing a technique before the present embodiment was conceived.

[0028] Fig.14 It means Fig.13 Figures of different conceptual technologies, (a) is a longitudinal sectional view showing its overall structure, (b) is a partially enlarged longitudinal sectional view showing its connection state, and (c) is a partially enlarged longitudinal sectional view showing its poor connection state.

[0029] Explanation of symbols

[0030] 10—pressure sensor unit, 11—pressure sensor chip, 24—terminal seat, 24b—bottom portion, 24h—through hole, 24s—side wall portion, 26—sealing material, 26a—adhesive for fixing terminal, 30—connector member, 32—diaphragm, 36 (36A to 36C), 37 (37A to 37C)—relay connection terminal, 36d, 36e, 37d—terminal piece, 36f—flat portion, 37e—bent piece, 37f—connection surface, 3 7c—bent shape, 37g—engaging piece, 37p—protrusion, 38—lead, 40—pin, 50—circuit substrate, 50r—corner recess, 50u—recessed wall electrode surface, 51, 53—terminal retaining portion, 51a, 51b, 53a—slit, 51p, 53p—recessed portion, 54—pillar shape portion, 71—contact, 73—connector, 100—pressure sensor, L—recessed distance, M—plating, S—conductive connecting material, SR—setting space. DETAILED DESCRIPTION

[0031] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Figures 1 to 8 It is a diagram 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 same.

[0032] 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.

[0033] 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.

[0034] 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.

[0035] 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.

[0036] 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.

[0037] 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 .

[0038] 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.

[0039] 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.

[0040] The pins 40 are arranged on the bottom portion 24b of the resin terminal block 24 formed in a short-sized, bottomed, roughly cylindrical shape. Two power terminals, one output signal terminal, and five adjustment terminals used during 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 roughly 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 respectively mounting and holding the relay connection terminals 36 (36A to 36C) and 37 (37A to 37C) described later in a group of three are arranged at symmetrical positions at the center of the cylinder.

[0041] 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 can be applied, but also adhesives such as those containing conductive materials can be applied. In addition, as described above, in addition to conductive connection using soldering and conductive adhesives, conductive connection can also be performed by welding (for example, spot welding using lasers, etc.), and the welding method does not need to be particularly limited.

[0042] 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.

[0043] 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 housed in the waterproof housing 20, and is waterproofed and fixed by filling a sealing material 26 such as a polyurethane resin. Here, the circuit substrate 50 is arranged in the installation space SR formed by the terminal block 24 and the terminal block cover 25, 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.

[0044] Furthermore, the pressure sensor unit 10 is assembled in a stacked order by placing the terminal block 24, the circuit substrate 50, and the terminal block cover 25 from the housing 12 fixed to the cover 28 connected to the connector member 30. After the relay connection terminals 36 and 37 are placed on the terminal retaining 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. Thereafter, the circuit substrate 50 is placed on the terminal pieces 36d and 37d of the relay connection terminals 36 and 37 and soldered to thereby 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 also be conductively connected by soldering, riveting, etc. In addition, a through hole or the like is opened on the bottom portion 24b of the terminal block 24 so that the assembly operation can be properly performed. For example, a through hole 24H (not shown) for the oil filling tube 44 is also opened.

[0045] In detail, Figure 3 as well as Figure 4 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.

[0046] 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 of the long strip shape are facing each other, so that the flat portion 36f between the terminal pieces 36d and 36e at the two ends extending in the parallel direction of the U-shaped shape is formed along 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-shaped 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 along the outer surface of the terminal holding portion 53, and a bent piece 37e is provided that is bent on 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 37f 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 substrate 50.

[0047] The terminal holding parts 51 and 53 are provided with slits 51a, 51b and 53a penetrating the side wall part (constituent part) 24s of the terminal seat 24 into which each terminal piece 36d, 36e and 37d of the relay connection terminals 36 and 37 can be inserted. Concave parts 51p and 53p are formed on the outer surface of the side wall part 24s of the terminal seat 24 adjacent to the terminal piece 36e and the bent piece 37e of the relay connection terminals 36 and 37, and the sealing material 26 filled in the waterproof housing 20 enters, so that the terminal seat 24 and the relay connection terminals 36 and 37 are fixed.

[0048] Here, if Figure 5 As shown, the relay connection terminal 36 is formed into a group of three relay connection terminals 36A to 36C of different shapes, and is formed into a shape inserted into the side wall portion 24s of the terminal seat 24 in a parallel state with the interval between the terminal pieces 36e being narrower than that of the terminal pieces 36d. Since the terminal piece 36e is connected to the pins 40 arranged in the same circle with the support 13 as the center corresponding to the small pressure sensor chip 11, the relay connection terminal 36 is formed into a shape extending in parallel with narrow intervals close to the center. In addition, the terminal piece 36d is connected to the recessed electrode surface 50u of the circuit substrate 50 described later, but in consideration of the insulation distance with the adjacent recessed electrode surface 50u and the workability of soldering, etc., it is formed into a shape extending in parallel with an interval wider than the terminal piece 36e. In addition, as Figure 5 As shown in (d), the relay connection terminal 36 is manufactured by punching out a set of three relay connection terminals 36A to 36C in a state of being integrated with a lead frame 36LF, and then bending the terminal pieces 36d and 36e with respect to the flat surface portion 36f.

[0049] In addition, if Figure 6 As shown, each relay connection terminal 37A to 37C of the relay connection terminal 37 is made into the same shape, and is formed into a shape in which the terminal piece 37d and the bent piece 37e are bent in the same direction and inserted into the inside of the side wall portion 24s of the terminal seat 24 and the recessed portion 53p. The relay connection terminal 37 is formed with a locking piece 37g formed by forming the terminal piece 37d with a narrow width relative to the wide connection surface 37f and the bent piece 37e, and bending both sides in the same direction to hook in a manner of biting into the upper part of the terminal holding portion 53. In addition, similarly to the recessed portion 53p for the bent piece 37e of the relay connection terminal 37 being formed in the terminal holding portion 53 of the side wall portion 24s, in the terminal seat 24, the recessed portion 51p for the terminal piece 36e of the relay connection terminal 36 is formed in the terminal holding portion 51 of the side wall portion 24s to form a slit 51b. Here, the concave portions 51p and 53p into which the terminal pieces 36e and the bent pieces 37e of the relay connection terminals 36 and 37 enter may be coated with a terminal fixing adhesive 26a and fixed before the sealing material 26 is filled into the waterproof housing 20. With such a structure, the relay connection terminals 36 and 37 can be prevented from falling off or being dislocated from the terminal base 24, and the sealing material 26 can be prevented from leaking into the terminal base 24 from the extremely small gaps of the slits 51a, 51b, and 53a portions of the insertion portions of the terminal pieces 36d, 36e, and 37d of the terminal base 24.

[0050] Thus, the relay connection terminal 36 can be installed in a state where the long terminal pieces 36d and 36e are inserted into the side wall portion 24s of the terminal seat 24 to prevent the terminal from being pulled out, and even if the bent piece 37e is shorter than the terminal piece 37d, the relay connection terminal 37 can be installed in a state where the engaging piece 37g is hooked in a manner that the terminal holding portion 53 is sandwiched between the bent pieces 37e to prevent the terminal from being pulled out. Therefore, the relay connection terminals 36 and 37 can be connected by spot welding the terminal piece 36e to the pin 40 in a stable posture, and can be connected by soldering the terminal pieces 36d and 37e to the circuit substrate 50 in a stable posture.

[0051] 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 with the electrode surface 50u of the circuit substrate 50 described later and enabling conductive connection. In addition, the plating M is also applied to the adjacent part of the connection surface 37f of the relay connection terminal 37, and the wettability of the solder is improved in the soldering with the core wire C of the lead 38, thereby reducing the occurrence of poor connection. Here, the relay connection terminals 36 and 37 are plated with M only in the area where soldering is required, and the plating M is not applied to the other areas, thereby suppressing the outflow of the molten solder. It is clear that in addition to setting the area where the wettability of the solder is improved by plating M as in this example, the soldering surface can also be kept in the state of the metal base surface, and the area that restricts the flow of the solder can be treated with a resist or coating.

[0052] like Figure 7 As 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 open on both the front and back sides perpendicular to the plane of the circuit substrate 50. The concave wall electrode surface 50u is formed so that the molten solder can easily penetrate from the outer peripheral end surface of the circuit substrate 50 to the entire (entire surface) semicircularly inwardly into the concave distance L and the inner surface is plated with excellent solder wettability M. 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 setting the inward concave shape of the concave wall surface to a semicircular shape, it is expected that the stress inside the concave wall surface 50u formed by the solder fillet acts evenly. In addition, in the manufacturing process of the circuit substrate 50, it is also possible to use the same processing tools as those used for processing the mounting holes of the mounting components and processing the outer shape of the circuit substrate 50. In the case of a rectangular shape, other processes and other tools such as processing using a disc-shaped cutter are required, but by making it semicircular, it is advantageous in terms of productivity and quality.

[0053] 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 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.

[0054] Therefore, if Figure 8 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 Figure 8 The 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 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 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.

[0055] Here, if it is not possible to conceive of a technical concept of placing the circuit substrate 50 on the terminal pieces 36d and 37d of the relay connection terminals 36 and 37 and soldering them as in the present embodiment, for example, Fig.13As shown, the connection portion 136d formed by bending one end of the relay connection terminal 136 is passed through the through hole 150h of the circular hole formed in the circuit substrate 150 and soldered. In such a case, it is necessary to ensure the connection area on the inner side of the circuit substrate 150, so it is difficult to arrange the parts on the outer peripheral side of the circuit substrate than the connection area, so the installation area on the circuit substrate 150 is also reduced. In addition, the circuit substrate 150 and the parts such as the terminal seat and the terminal seat cover associated therewith also need to be enlarged according to the installation parts and circuit layout. In addition, the position of the connection portion 136d and the amount of molten solder S attached are deviated, and the connection quality and workability are reduced. In addition, if soldering is performed, the so-called "solder ball" may be generated. It is believed that the short circuit of the circuit and other undesirable conditions occur due to the scattering of the solder ball to the undesirable part. As a countermeasure, in addition to suppressing the occurrence of solder balls such as soldering conditions, it is also considered to mask the circuit substrate itself to prevent the solder balls from adhering to prevent the solder balls from scattering to the circuit. By performing soldering on the outer peripheral side of the circuit board as in the present embodiment, the range of scattering can be reduced, or masking on the circuit board can be performed by a simple method, which also has the effect of suppressing the occurrence of defects.

[0056] In addition, it is usually considered to adopt a structure in which the terminal piece is placed on the upper surface side of the soldering connection portion formed on the circuit substrate. In this case, after the circuit substrate is placed on the terminal seat, the terminal piece must be bent toward the upper surface side of the substrate. That is, after the terminal seat of the circuit substrate is placed, a process of bending the terminal piece is required, and due to the gap between the terminal piece, the substrate and the terminal are not in close contact, and there is a possibility of poor soldering. Moreover, even if it is further close to the present embodiment, for example, Fig.14 As shown in (a), a connection portion 151u is formed on the outer peripheral end surface of the circuit substrate 150. If the terminal piece 146d of the relay connection terminal 146 is smaller than the connection portion 151u, Fig.14 As shown in (b), the formation of the solder fillet is insufficient, or Fig.14 As shown in (c), the molten solder S is unstable and cannot maintain an appropriate posture, and there is a high possibility that it is fixed (solidified) in an inclined and inappropriate posture.

[0057] Thus, in the pressure sensor unit 10 of the pressure sensor 100 of the present embodiment, the terminal pieces 36d, 36e, 37d of the relay connection terminals 36, 37 are inserted into the slits 51a, 51b, 53a of the terminal seat 24, the terminal seat 24 is placed on the housing 12, the terminal piece 36e is spot welded to the pin 40, and then the circuit substrate 50 is further placed on the remaining terminal pieces 36d, 37d, and the recessed electrode surface 50u of the circuit substrate 50 and the terminal pieces 36d, 37d are soft soldered, thereby performing an assembly operation (manufacturing method) of connecting the pressure sensor chip 11 to the external device A with high quality.

[0058] Therefore, it is possible to construct a pressure sensor unit 10 in which the pressure sensor chip 11 and the circuit board 50 are easily assembled with a simple structure and are conductively connected with high reliability, and to provide a pressure sensor 100 equipped with the pressure sensor unit 10 .

[0059] Here, as a first other mode of this embodiment, Fig. 9 As shown in (a), the terminal piece 37d of the relay connection terminal 37 can be moved without resistance in the removal direction (penetration reverse direction) by simply inserting the terminal piece 37d of the relay connection terminal 37 into the slit 53a of the terminal seat 24 along the forward direction, so it is advantageous to have a shape that contacts the inner surface of the slit 53a of the side wall portion (constituent portion) 24s that penetrates the terminal seat 24 to suppress movement. Therefore, on the surface of the terminal piece 37d of the relay connection terminal 37, for example Fig. 9 The protrusion 37p shown in (b) is caught on the inner surface of the slit 53a, or a Fig. 9 It is advantageous to form the bent shape 37c shown in (b) so as to press the inner surface of the slit 53a.

[0060] Furthermore, as a second alternative mode of this embodiment, the relay connection terminal 37 which is inserted into the slit 53a of the terminal base 24 and soldered to the concave wall electrode surface 50u of the circuit substrate 50 also needs to solder the core wire C of the lead wire 38 from the external device A to the connection surface 37f. Fig.10 As shown by the larger arrow in (b), during the soldering operation, the solder S that connects the concave wall electrode surface 50u of the circuit substrate 50 to the terminal piece 37d may melt again and flow to the connection surface 37f side. However, by making the base material of the relay connection terminals 36 and 37 itself with a conductive material whose wettability of the solder is worse than that of the plating M, as shown in FIG. Fig.10 As shown by the smaller arrow in (a), it is possible to more actively and effectively suppress the molten solder from flowing out to areas outside the plating M.

[0061] In addition, as a third other mode of this embodiment, Fig.11As shown, a male connector 73 having a contact (terminal component) 71 that is conductively connected to the circuit substrate 50 can also be prepared, and it can also be easily detached (connected / disconnected) relative to the connector 73 (the female connector not shown in the figure from the external device can also be reversed). In this third other mode, since the circuit substrate 50 is conductively connected via the contact 71, the terminal holding portion 53 can be omitted and supported on the terminal seat 24 together with the relay connection terminal 37 and the lead 38. In addition, the connector 73 is also provided on the terminal seat 24 instead of the terminal seat cover 25. Among them, in this third other mode, after the contact 71 is conductively connected to the circuit substrate 50, the terminal piece 36e of the relay connection terminal 36 is spot welded to the pin 40, and then the terminal piece 36d of the relay connection terminal 36 is soldered to the circuit substrate 50 and covers the outer cover of the connector 73, thereby assembling and manufacturing. In addition, after the assembly operation, the sealing material 26 is filled between the terminal seat 24 and the connector 73 between the waterproof housing 20.

[0062] In addition, as a fourth other mode of this embodiment, Fig.12 As shown, a rivet plate 75 is installed on the connector 73 instead of the waterproof housing 20 in the third other embodiment. The rivet plate 75 is riveted to the rivet portion 73s of the connector 73 and integrated so as to cover the outer periphery of the housing 12 and the terminal block 24 and have a certain degree of waterproof function, thereby becoming a structure in which the filling sealing material 26 can be omitted.

[0063] In addition, as a fifth other mode of this embodiment, although the illustration is omitted, it can of course be unified as Figure 1 One of the relay connection terminals 36 and 37 of the present embodiment is shared. Specifically, the relay connection terminal 37 of the terminal component may be replaced by the lead wire 38 passing through the terminal seat cover 25 and being connected to the circuit substrate 50 by direct soldering or the like. Alternatively, the relay connection terminal 37 may be kept as it is, the relay connection terminal 36 of the connection component may be replaced by the lead wire 38 passing through the terminal seat cover 25 and being connected to the circuit substrate 50 by direct soldering or the like.

[0064] 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, It is characterized in that have: a circuit substrate configured to be interposed between the external device and connected to the sensor; and 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, One or both of the connection member and the terminal member is formed with a connection area connected to the circuit substrate, and the connection area is provided with a support area of ​​a size capable of placing the circuit substrate. The connection area of ​​the circuit substrate is located on the support area in a manner of being placed on one or both of the connection component and the terminal component, and is constructed to be capable of performing conductive connection operations between the connection area of ​​the circuit substrate and the connection area of ​​one or both of the connection component and the terminal component.

2. The pressure sensor according to claim 1, It is characterized in that The conductive connection between the connection region of the circuit board and the connection region of one or both of the connection member and the terminal member is performed by soldering, welding, or coating of a conductive material.

3. The pressure sensor according to claim 1, It is characterized in that The connecting member is formed in a long strip shape and has an end piece on one end side and an end piece on the other end side located at both ends of the extension. The connecting component is formed so that, when the one-end side end piece and the other-end side end piece are opposite to each other, the one-end side end piece constituting the connection area of ​​the connecting component and connected to the circuit substrate is located on the outer peripheral side of the circuit substrate, and the other-end side end piece is located on the inner side of the outer peripheral side of the circuit substrate and can be connected to the sensor side.

4. The pressure sensor according to claim 1, It is characterized in that A connection region of one or both of the connection member and the terminal member is located at an outer peripheral end portion of the circuit substrate and is conductively connected.

5. The pressure sensor according to claim 1, It is characterized in that A concave wall surface that is concave inward at an outer peripheral end of the circuit substrate is formed as a connection region thereof, and the connection region that is conductively connected to one or both of the connection member and the terminal member is conductively connected to the concave wall surface.

6. The pressure sensor according to claim 1, It is characterized in that The circuit substrate, the connection member, and the connection portion of the terminal member are provided in a member forming a space that blocks communication of a fluid.

7. The pressure sensor according to claim 5, It is characterized in that The concave wall surface is formed so that the inward concave distance is larger than the opening width of the outer peripheral end surface of the circuit substrate.

8. The pressure sensor according to claim 5, It is characterized in that The concave wall surface has a semicircular shape that is concave inward from the outer peripheral end surface of the circuit substrate.

9. The pressure sensor according to claim 1, It is characterized in that One or both of the connection member and the terminal member includes a connection region having excellent solder wettability, and a region having poorer solder wettability than the connection region is formed outside the connection region.

10. The pressure sensor according to claim 1, It is characterized in that A terminal seat is provided for supporting one or both of the connection member and the terminal member. The connecting member and the electrically connectable and extendable terminal piece of the terminal member penetrate through the component of the terminal base and are held. The terminal piece of both or one of the connecting member and the terminal member is shaped to contact the inner surface of the structure of the component penetrating the terminal seat to suppress movement in one or both of the forward and reverse directions of the penetration.

11. A method for manufacturing a pressure sensor, the pressure sensor comprising a sensor unit having a sensor connected to an external device, It is characterized in that The sensor unit comprises: a circuit substrate, which is arranged to be interposed between the sensor and the external device and connected to the sensor; and one or both of a connecting component located between the sensor and the circuit substrate and conductively connected to the sensor and the circuit substrate, and a terminal component conductively connected to the circuit substrate for conductively connecting the circuit substrate to the external device. One or both of the connection member and the terminal member is formed with a connection area connected to the circuit substrate, and the connection area is provided with a support area of ​​a size that can stably place the circuit substrate. The connection area of ​​the circuit substrate is located on the support area in a manner such that it is placed on one or both of the connection component and the terminal component, and a conductive connection operation is performed between the connection area of ​​the circuit substrate and the connection area of ​​one or both of the connection component and the terminal component.

12. The method for manufacturing a pressure sensor according to claim 11, It is characterized in that The connection region of the circuit substrate and the connection regions of one or both of the connection member and the terminal member are conductively connected by soldering, welding, or coating of a conductive material.

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