JP2012181127A - Pressure sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique for forming a stable electrical connection between a pressure detection element and a substrate.SOLUTION: A pressure sensor comprises: a cylindrical first case with a bottom; a cylindrical second case; and a cylindrical connection member having elasticity which is arranged between the first and second cases for connecting the first and second cases. The pressure sensor further comprises: a pressure detection element; a base; a substrate on which a circuit part is arranged; and an electrical wiring path for electrically connecting the pressure detection element with the circuit part. In the connection member, an opening for forming a bonding wire, by wire bonding, from the outside of the connection member is formed.

Description

  The present invention relates to a pressure sensor for detecting pressure in a combustion chamber of an internal combustion engine.

  As a pressure sensor, for example, a sensor that measures the in-cylinder combustion pressure of an internal combustion engine such as an automobile engine is known. The combustion state is controlled by measuring the in-cylinder combustion pressure. Such a pressure sensor includes a pressure detection element, a pedestal on which the pressure detection element abuts, a circuit for processing a detection signal, a substrate on which the circuit is installed, and a cylindrical shape that houses the pressure detection element and the substrate. A case (for example, Patent Document 1). The pressure detection element and the circuit are electrically connected by an electric wiring path. This electrical wiring path includes not only the electrical wiring provided on the substrate and the pedestal wiring provided on the pedestal, but also bonding wires for connecting the electrical wiring on the substrate and the electrical wiring on the pedestal.

  The cylindrical case includes an element case for accommodating a pressure detection element, a substrate case in which a substrate is installed inside, and the like. The case may have a cylindrical connection member that connects the element case and the substrate case (for example, Patent Document 2). This connecting member has elasticity in order to suppress external force applied to the element case from being transmitted to the substrate case.

JP 2009-229039 A JP 2010-139152 A

  Conventionally, after a pressure sensor and a substrate are connected by an electrical wiring path, a pressure sensor accommodates the pressure detection element and the circuit board in the case by connecting the element case, the connecting member, and the substrate case, respectively. Yes. However, in the pressure sensor manufactured by such a manufacturing process, the electrical connection between the pressure detection element and the substrate becomes unstable, and the reliability of the pressure sensor may be lowered. For example, in a state before the element case, the connection member, and the substrate case are connected, the positional relationship between the pedestal and the substrate is not stable, and a bonding wire may not be formed at a desired position.

  Accordingly, an object of the present invention is to provide a technique for forming a stable electrical connection between a pressure detection element and a substrate.

[Application Example 1] A bottomed cylindrical first case extending in the axial direction and having a tip portion forming the bottom;
A cylindrical second case extending in the axial direction, arranged on the rear end side of the first case;
A cylindrical connecting member disposed between the first and second cases and connecting the first and second cases, wherein the connecting member has elasticity;
A pressure detecting element housed in the first case for detecting pressure through the bottom;
A pedestal disposed on the rear end side of the pressure detection element and accommodated in the first case and the connection member, the pedestal contacting the pressure detection element;
A circuit unit disposed on the rear end side of the pedestal and accommodated between the second case and the connection member, the circuit unit for processing a detection signal of the pressure detection element The placed substrate, and
An electrical wiring path that is housed in the first case, in the second case, and in the connection member and electrically connects the pressure detection element and the circuit unit; In the pressure sensor,
The electrical wiring path is accommodated in the connection member of the first pedestal wiring path formed at the rear end of the pedestal accommodated in the connection member of the pedestal portion and the portion of the substrate. A first substrate wiring path formed at the tip of the substrate, and a bonding wire for electrically connecting the first pedestal wiring path and the first substrate wiring path;
The pressure sensor, wherein the connection member has a wire opening for forming the bonding wire by wire bonding from the outside of the connection member.

  According to the pressure sensor described in Application Example 1, wire bonding can be performed from the outside through the wire opening of the connection member. Therefore, after the first case, the second case, and the connection member are connected and the positional relationship between the first base wiring path and the first substrate wiring path is fixed, the two are electrically connected by wire bonding. be able to. Therefore, a bonding wire can be formed at a desired position, and a stable electrical connection between the pressure detection element and the substrate can be achieved.

[Application Example 2] In the pressure sensor according to Application Example 1,
The first pedestal wiring path includes a pedestal side pad,
The first substrate wiring path includes a substrate side pad electrically connected to the pedestal side pad by the bonding wire,
The pressure sensor, wherein the wire opening is one opening formed at a position where the pedestal side pad and the board side pad are visible from the outside of the connection member.
According to the pressure sensor described in the application example 2, all of the bonding wire for performing wire bonding, the pedestal side pad, and the substrate side pad can be visually recognized in one wire opening, and the pedestal side pad and The board-side pad can be easily electrically connected by wire bonding.

[Application Example 3] In the pressure sensor according to Application Example 2,
The pedestal side pad is formed on a pedestal plane substantially parallel to the axial direction of the outer surface of the pedestal rear end,
The wire opening is formed at a position where the pedestal-side pad and the substrate-side pad are visible when the connection member is viewed from a direction perpendicular to the pedestal plane and passing through the pedestal-side pad. The pressure sensor characterized by the above-mentioned.
According to the pressure sensor described in Application Example 3, the wire bonding jig is passed through the wire opening from the direction perpendicular to the pedestal plane, and the bonding wire is connected to the pedestal side pad and the substrate side pad within the connection member. Can do. Thereby, a bonding wire can be formed with high accuracy. Therefore, more stable electrical connection between the pressure detection element and the substrate can be achieved.

[Application Example 4] In the pressure sensor according to any one of Application Examples 1 to 3,
A pressure sensor characterized in that a plurality of openings having the same shape including the wire openings are formed in the connection member at substantially constant intervals in the circumferential direction of the connection member.
According to the pressure sensor described in Application Example 4, stress concentration can be alleviated by forming the openings in the connection member at substantially constant intervals in the circumferential direction. Therefore, possibility that a part of connection member will be damaged can be reduced.

  In addition, this invention can be implement | achieved with various forms, for example, can be implement | achieved in aspects, such as a pressure sensor, the manufacturing method of a pressure sensor, and a vehicle equipped with the pressure sensor.

(A) It is an external appearance perspective view for demonstrating the pressure sensor 1. FIG. (B) It is a cross-sectional perspective view for demonstrating the pressure sensor 1. FIG. (A) It is a perspective view for demonstrating the 1st case 30 and the pressure detection unit 90. FIG. (B) It is a cross-sectional perspective view for demonstrating the 1st case 30 and the pressure detection unit 90. FIG. FIG. 4A is a perspective view of the vicinity of a second case 60 of the pressure sensor 1. (B) It is a perspective view of the board | substrate of the pressure sensor 1. FIG. 4 is a perspective view for explaining a connecting member 70. FIG. It is a figure for demonstrating the electrical wiring path 95 which connects the pressure detection element 46 and the circuit part 68. FIG. It is a figure for demonstrating the formation position of the opening part 72p for wires.

Next, embodiments of the present invention will be described in the following order.
A. Example:
B. Variations:

A. Example:
A-1. Overall configuration of the pressure sensor 1:
FIG. 1 is a first diagram for explaining the pressure sensor 1. FIG. 1A is an external perspective view of a pressure sensor 1 according to the present invention, and FIG. 1B is a cross-sectional perspective view of the pressure sensor 1. For ease of explanation, the reference numeral 10 side is the front end side, and the reference numeral 28 side is the rear end side. The pressure sensor 1 is attached to, for example, a cylinder head of an engine combustion chamber of an automobile and detects the combustion pressure of the engine combustion chamber.

  As shown in FIGS. 1A and 1B, the pressure sensor 1 includes a cylindrical seal portion 10, a cylindrical housing 20, a tool engagement portion 26, and three cables 28. . The seal portion 10 is attached to the front end side of the housing 20, and shuts off the engine combustion chamber and the outside air when the pressure sensor 1 is attached to a predetermined place (for example, a mounting hole of a cylinder head of the engine combustion chamber). .

  The housing 20 is made of a metal material (for example, carbon steel such as S45C). The housing 20 extends in the direction of the axis CL, and a screw portion 24 for attaching the pressure sensor 1 to a predetermined place is formed in the middle. In addition, in FIG. 1, illustration of the thread groove formed in the outer surface of the thread part 24 is abbreviate | omitted.

  Further, the tool engaging portion 26 is formed in a rear end side portion of the portion of the housing 20 with respect to a position where the screw portion 24 is formed. The tool engaging portion 26 has a hexagonal outer peripheral shape so that a predetermined tool (for example, a spanner or a wrench) can be engaged. The tool engaging portion 26 is used when the screw portion 24 is attached to a predetermined place.

  The cable 28 transmits a detection signal for detecting pressure to a control device mounted in an automobile or the like, or transmits a start signal for starting the circuit unit 68 included in the pressure sensor 1 from the control device to the circuit unit 68. To do. The rear end side of the cable 28 extends from the rear end of the housing 20 to the outside of the housing 20 and is connected to a control device. The front end side of the cable 28 is housed inside the housing 20 and is connected to a terminal 66 attached to the rear end side of the board unit 69.

  As shown in FIG. 1B, a cylindrical first case 30, a cylindrical connecting member 70, and a cylindrical second case 60 are arranged on the inner side of the housing 20 in order from the distal end side. Has been placed. The first case 30, the connection member 70, and the second case 60 are made of a metal material. Further, in an inner space formed by connecting the members 30, 70, 60, a pressure detection unit 90 for detecting the pressure in the engine combustion chamber and a substrate unit 69 for processing a detection signal from the pressure detection unit 90 are provided. Is arranged. The pressure detection element 46 in the pressure detection unit 90 and the circuit unit 68 in the substrate unit 69 are electrically connected by an electrical wiring path described later. Details of the electrical wiring path will be described later.

A-2. Detailed configuration of the pressure sensor 1:
FIG. 2 is a diagram for explaining the first case 30 and the pressure detection unit 90. Here, FIG. 2 illustrates a configuration in the vicinity of the first case 30 of the pressure sensor 1. Further, the housing 20 (FIG. 1) is omitted for easy understanding. FIG. 2A is an external perspective view of the first case 30 and the seal portion 10 in the pressure sensor 1. FIG. 2B is a cross-sectional perspective view of FIG.

  As shown in FIG. 2B, the cylindrical first case 30 includes a bottom plate 40 that forms a bottom portion on the tip side. The bottom plate 40 is attached by welding or the like and constitutes a part of the first case 30. The bottom plate 40 may be integrally formed as the first case 30 instead of being separated from the first case 30 main body.

  The first case 30 includes a cylindrical tip case 32 and a cylindrical (annular) pressing member 34 attached to the rear end side inner peripheral surface of the tip case 32 by welding or the like. The bottom plate 40, the tip case 32, and the pressing member 34 are formed of a metal material. The bottom plate 40 is disposed toward the engine combustion chamber. The bottom plate 40 bends in the direction of the axis CL according to the combustion pressure in the engine combustion chamber, whereby the combustion pressure is transmitted to the pressure detection element 46. Further, the tip side portion of the tip case 32 is joined to the tip side portion of the housing 20 by welding or the like.

  The pressure detection unit 90 includes the above-described bottom plate 40, a pressure transmission member 42, an intermediate member 44, a pressure detection element 46, a pedestal 50, and the above-described pressing member 34. The pressure transmission member 42 is a rod-shaped member made of a ceramic material. The tip of the pressure transmission member 42 is sandwiched between the bottom plate 40 and the intermediate member 44. The intermediate member 44 is a solid (high density) block-like member made of a ceramic material. The area of the cross section orthogonal to the direction of the axis CL is larger in the intermediate member 44 than in the pressure transmission member 42. The intermediate member 44 is disposed between the pressure transmission member 42 and the pressure detection element 46, and suppresses the pressure transmitted from the pressure transmission member 42 from being transmitted to the pressure detection element 46 in a biased manner.

  The pressure detection element 46 outputs an electrical signal corresponding to the strain when pressure is applied. Specifically, the pressure detection element 46 is in contact with the sensor element 46a and the front and rear end faces of the sensor element 46a, and the first and second glass plates 46b and 46c disposed so as to sandwich the sensor element 46a. And comprising. A piezoresistor is formed on the front end surface of the sensor element 46a, and the pressure is detected from a change in resistance value when the sensor element 46a is deformed by deformation. In addition, as the pressure detecting element 46, a piezoelectric element such as quartz can be used. The first glass plate 46 b of the pressure detection element 46 is joined to the intermediate member 44, and the second glass plate 46 b is joined to the pedestal 50.

  A pedestal 50 is disposed on the rear end side of the pressure detection element 46. The pedestal 50 is formed of an insulating member. In this embodiment, the pedestal 50 is made of alumina which is an insulating ceramic. The pedestal 50 includes an element installation part 50a that is bonded to and contacts the pressure detection element 46, and an extending part 50b that extends from the element installation part 50a to the rear end side. The rear end surface of the element installation portion 50a abuts against the tip of the pressing member 34, so that the position of the base 50 is fixed and the base 50 is not displaced in the direction of the axis CL. The rear end surface of the element installation portion 50a and the front end surface of the pressing member 34 may be joined by brazing or the like.

  In the pressure detection unit 90, the pressure transmission member 42, the intermediate member 44, the pressure detection element 46, and the tip side portion of the base 50 are accommodated inside the first case 30. Note that a pedestal rear end portion 57 which is a rear end side portion protruding from the rear end of the first case 30 among the portions of the pedestal 50 is accommodated inside the connection member 70 (FIG. 1). A first pedestal wiring path 52 is formed on the outer surface of the pedestal 50 including the upper surface of the pedestal rear end 57. A pedestal-side pad 58 is formed in a portion of the first pedestal wiring path 52 that protrudes from the first case 30 to the rear end side. Although the details will be described later, the first pedestal wiring path 52 is electrically connected to the pressure detection element 46.

  FIG. 3 illustrates a configuration in the vicinity of the second case 60 of the pressure sensor 1. Further, the illustration of the housing 20 is omitted for easy understanding. FIG. 3A is an external perspective view of the second case 60 in the pressure sensor 1. FIG. 3B is an external perspective view of the board unit 69, and the second case 60 is not shown.

  As shown in FIG. 3A, the second case 60 extends in the direction of the axis line CL and accommodates the substrate unit 69 inside. Specifically, a part of the inner surface of the second case 60 forms a plane extending in the direction of the axis CL, and the substrate unit 69 is fixed on the plane.

  As shown in FIG. 3B, the board unit 69 includes a circuit unit 68 and a board 62 on which the circuit unit 68 is installed. The circuit unit 68 performs processing such as amplification on the detection signal. In the substrate 62, a first substrate wiring path 61 extending from the circuit portion 68 toward the front end side and a second substrate wiring path 67 extending from the circuit portion 68 toward the rear end side are formed. A portion of the first substrate wiring path 61 that protrudes from the second case 60 toward the tip side is provided with a substrate-side pad 64 that is electrically connected to the pedestal-side pad 58 (FIG. 2) by wire bonding. 62 is formed on the outer surface. The second board wiring path 67 is electrically connected to the three terminals 66 disposed on the rear end side of the circuit portion 68 of the board 62.

  FIG. 4 is a view for explaining the connection member 70. In FIG. 4, the external appearance perspective view of the 1st case 30, the connection member 70, and the 2nd case 60 vicinity is shown. In addition, illustration of the housing 20 (FIG. 1) is abbreviate | omitted for easy understanding.

  The connection member 70 is made of spring steel such as stainless steel 403 and has elasticity. The connection member 70 is disposed between the first case 30 and the second case 60 and connects the first and second cases 30 and 60. Specifically, the inner peripheral surface of the front end side portion of the connection member 70 is joined to the outer peripheral surface of the pressing member 34 by welding or the like, and the inner peripheral surface of the rear end side portion of the connection member 70 is the outer periphery of the second case 60. Joined to the surface by welding or the like. The connection member 70 is elastically deformed when an external force is applied to the first case 30 due to engine vibration or the like, and suppresses the transmission of the external force to the second case 60. A plurality of openings 72 (six openings 72 in this embodiment) are formed in the connection member 70 at substantially constant intervals in the circumferential direction. The plurality of openings 72 have the same shape. In this manner, by forming the plurality of openings 72 having the same shape in the circumferential direction at substantially constant intervals, it can be elastically deformed uniformly in the direction perpendicular to the axis CL direction. That is, when an external force is applied to the connection member 70 due to vibration or the like, the stress concentration can be relaxed and the possibility that a part of the connection member 70 is damaged can be reduced. In addition, in order to distinguish the opening for forming the 2nd bonding wire 80 mentioned later among the some opening parts 72 from another opening, it is also called the opening part 72p for wires. In the present embodiment, the connection member 70 has two wire openings 72p. The details of the wire opening 72p will be described later.

  FIG. 5 is a diagram for explaining the electrical wiring path 95 that connects the pressure detection element 46 and the circuit unit 68. FIG. 5 mainly illustrates a configuration necessary for explanation for easy understanding. Further, in FIG. 5, the area accommodated inside the first case 30 is the first case area 30 </ b> R, the area accommodated inside the connection member 70 is the connection member area 70 </ b> R, and the inside of the second case 60. An area accommodated in the case is illustrated as a second case area 60R.

  Two electrical wiring paths 95 are formed. The electrical wiring path 95 includes a first bonding wire 51, a first pedestal wiring path 52, a second bonding wire 80, and a first substrate wiring path 61. The electrical wiring path 95 is accommodated over the first case 30, the connection member 70, and the second case 60. Each element 51, 52, 80, 65 constituting the electric wiring path 95 is formed of a conductive material such as Au or Al.

  The first bonding wire 51 electrically connects the pressure detection element 46 and the first pedestal wiring path 52 formed on the outer surface of the pedestal 50. The first bonding wire 51 is formed by wire bonding.

  The first pedestal wiring path 52 is formed from the element installation portion 50a of the pedestal 50 to the extending portion 50b. Specifically, the tip end surface 50a1 that contacts the pressure detecting element 46 of the element setting portion 50a, the setting portion upper surface 52a2 that is orthogonal to the tip surface 50a1, and the rear end surface that is orthogonal to the setting portion upper surface 52a2 and faces the tip surface 50a1. 50 a 3 (not shown) and the extending portion 50 b are formed to extend over the extending portion upper surface 50 b 2 that is substantially parallel to the installation portion upper surface 52 a 2 and located on the same side. Here, the installation portion upper surface 52a and the extending portion upper surface 50b2 are substantially parallel to the axis line CL direction. The first pedestal wiring path 52 is formed from the first case region 30R to the connection member region 70R. Further, the first pedestal wiring path 52 includes a pedestal side pad 58 formed on a pedestal plane 50b3 located at the pedestal rear end 57 of the extended portion upper surface 50b2. The first pedestal wiring path 52 is formed by a method such as printing, plating, vapor deposition, or sputtering.

  The first substrate wiring path 61 passes through the substrate 62 and extends from the circuit portion 68 to the rear end side. Further, the first substrate wiring path 61 reaches the substrate tip 65 located in the connection member region 70 </ b> R in the substrate 62. A substrate-side pad 64 that is a terminal portion of the first substrate wiring path 61 is formed on the substrate plane 62b3 that is substantially parallel to the pedestal plane 50b3 in the surface of the substrate front end portion 65 and located on the same side. Yes.

  The second bonding wire 80 electrically connects the pedestal 50, which is a different member, and the pedestal side pad 58 and the substrate side pad 64 formed on the surface of the substrate 62. The second bonding wire 80 is formed by wire bonding.

  FIG. 6 is a diagram for explaining a position where the wire opening 72p is formed. 6 is a diagram illustrating the appearance of the seal portion 10, the first case 30, the connection member 70, and the second case 60 in the pressure sensor 1. FIG. 6 is an enlarged view in which the vicinity of the connection member 70 is enlarged. FIG. 6 is a view when the connection member 70 is viewed from the direction above the pedestal plane 50b3 and the substrate plane 62b3 and perpendicular to the pedestal plane 50b3 and the substrate plane 62b3.

  As shown in the enlarged view of FIG. 6, each wire opening 72 p is a direction perpendicular to the pedestal plane 50 b 3 and the board plane 62 b 3 in the connection member 70 and passes through the pedestal side pad 58 and the board side pad 64. When the connection member 70 is viewed from above, the pedestal side pad 58 and the corresponding substrate side pad 64 are formed so as to be visible. In other words, one wire opening 72p is located immediately above the pedestal side pad 58 and the board side pad 64 that are electrically connected. That is, a wire opening 72 p is formed in the connection member 70 corresponding to the pedestal side pad 58 and the board side pad 64 that are electrically connected.

A-3. effect:
In the pressure sensor 1, a wire opening 72 p is formed in the connection member 70 so that the base side pad 58 and the board side pad 64 can be visually recognized from the outside of the connection member 70 (FIG. 6). Therefore, the pressure sensor 1 can be manufactured by the following procedure. That is, as shown in FIG. 2A, a structure in which the pressure detection unit 90 including the pedestal 50 in which the first pedestal wiring path 52 is formed is accommodated inside the first case 30, and FIG. As shown in FIG. 2, a structure is prepared in which a substrate unit 69 including a substrate 62 on which a first substrate wiring path 61 is formed is accommodated inside a second case 60. Next, the two structures are connected by the connecting member 70 as shown in FIG. Next, the second bonding wire 80 is formed through the wire opening 72p. Specifically, the second bonding wire 80 is formed by passing a capillary (wire bonding jig) through the wire opening 72p.

  As described above, after the base 50 is accommodated and fixed inside the first case 30 and the substrate 62 is accommodated and fixed inside the second case 60, the first and second cases 30 and 60 are attached. The connection member 70 is used for connection. Therefore, the second bonding wire 80 can be formed in a state in which the positional relationship between the pedestal side pad 58 formed on the pedestal 50 and the substrate side pad 64 formed on the substrate 62 is stable. Therefore, since the pedestal side pad 58 and the substrate side pad 64 can be accurately connected by the second bonding wire 80, stable electrical connection between the pressure detecting element 46 and the substrate 62 can be achieved. Thereby, the accurate detection signal of the pressure detection element 46 is more reliably transmitted to the circuit unit 68 through the electric wiring path 95. As described above, since the detection signal of the pressure detection element 46 can be output to the outside with high accuracy by the cable 28, the reliability of the pressure sensor 1 can be improved.

  In general, the bonding wire can be formed with higher accuracy by wire bonding by moving the capillary perpendicular to the surface on which the bonding wire is formed. Here, in the above embodiment, the wire opening 72 p is formed immediately above the substrate-side pad 64 and the base-side pad 58. That is, all of the bonding wire 80 for performing wire bonding, the pedestal side pad 58, and the substrate side pad 64 can be visually recognized in one wire opening 72p. Therefore, the second bonding wire 80 can be formed by vertically moving the capillary. As described above, a more stable electrical connection between the pressure detection element 46 and the substrate 62 can be achieved.

  Moreover, in the said Example, the connection member 70 has the four opening parts 72 other than the two opening parts 72p for wires, and both opening parts 72p and 72 are the same shape. Furthermore, six openings 72 and 72p are formed at substantially constant intervals in the circumferential direction. Therefore, the connecting member 70 can be elastically deformed uniformly in a direction perpendicular to the direction of the axis CL. Thereby, stress concentration can be relieved and possibility that a part of connecting member 70 will be damaged can be reduced.

B. Variations:
In addition, elements other than the elements described in the independent claims of the claims in the constituent elements in the above-described embodiments are additional elements and can be omitted as appropriate. Further, the present invention is not limited to the above-described examples and embodiments, and can be implemented in various forms without departing from the gist thereof. For example, the following modifications are possible.

B-1. First modification:
In the above-described embodiment, the number (two in this embodiment) corresponding to the number of pedestal-side pads 58 and substrate-side pads 64 (two in this embodiment) electrically connected by the second bonding wires 80 is used. Although the wire opening 72p is formed in the connection member 70, the present invention is not limited to this. The wire openings 72p may not be formed in the connection member 70 in correspondence with the number of the pedestal side pads 58 and the board side pads 64 that are electrically connected. For example, in the above embodiment, one wire opening 72p for forming two second bonding wires 80 is formed for the two pedestal side pads 58 and the two substrate side pads 64 that are electrically connected. You may form in the connection member 70. FIG. Specifically, one wire opening 72 p is formed at a position where the two base-side pads 58 and the two board-side pads 64 that are electrically connected can be viewed from the outside of the connection member 70. Even in this case, the pedestal side pad 58 and the substrate side pad 64 can be connected by wire bonding after the first case 30, the second case 60, and the connection member 70 are connected, as in the above embodiment.

B-2. Second modification:
In the above embodiment, the connection member 70 is formed with four openings 72 in addition to the two wire openings 72p. However, openings other than the wire openings 72p may not be formed. The number of openings 72 is not limited to this. Even in this case, the pedestal side pad 58 and the substrate side pad 64 can be connected by wire bonding after the first case 30, the second case 60, and the connection member 70 are connected, as in the above embodiment.

B-3. Third modification:
In the said Example, the length of the opening part 72 (72p) formed in the connection member 70 and the length between the adjacent opening parts 72 (72p) are the substantially same length about the circumferential direction of the connection member 70. FIG. It is preferable. By doing so, the connecting member 70 can be elastically deformed uniformly in a direction perpendicular to the direction of the axis CL.

B-4. Fourth modification:
In the above embodiment, when the connecting member 70 is viewed from a direction perpendicular to the pedestal plane 50b3 and passing through the pedestal side pad 58 (also referred to as “pad vertical direction”), the pedestal side pad 58 and It is preferable that the wire opening 72p is formed in the connection member 70 so that the substrate-side pad 64 is positioned substantially at the center of the wire opening 72p. In other words, when the connection member 70 is viewed from the pad vertical direction, the pedestal side pad 58 and the board side pad 64 are arranged at a predetermined distance from the connection member 70 that defines the opening of the wire opening 72p. Is preferred. By doing so, the possibility that the capillary hits the connection member 70 at the periphery of the wire opening 72p can be reduced. Thereby, the 2nd bonding wire 80 can be smoothly formed in an exact position.

DESCRIPTION OF SYMBOLS 1 ... Pressure sensor 10 ... Seal part 20 ... Housing 24 ... Screw part 26 ... Tool engaging part 28 ... Cable 30 ... 1st case 30R ... 1st case area | region 32 ... Tip case 34 ... Pressing member 40 ... Bottom plate 42 ... Pressure transmission member 44 ... Intermediate member 46 ... Pressure detection element 46a ... Sensor element 46b ... First glass plate 46c ... Second glass plate 50 ... Base 50a ... Element installation part 50b ... Extension part 50a1 ... Front end face 50a3 ... Rear end face 50b2 ... Extension part upper surface 50b3 ... Base plane 51 ... First bonding wire 52 ... First base wiring path 52a2 ... Installation part upper surface 57 ... Base rear end part 58 ... Base side pad 60 ... Second case 60R ... Second Case region 61 ... first substrate wiring path 62 ... substrate 62b3 ... substrate plane 64 ... substrate side pad 65 ... substrate tip 66 ... terminal 67 ... first 2 substrate wiring path 68... Circuit portion 69... Substrate unit 70 .. connection member 70 R... Connection member region 72 .. opening 72 p .. wire opening 80 .. second bonding wire 90.

Claims (4)

A bottomed cylindrical first case extending in the axial direction, the tip side forming the bottom;
A cylindrical second case extending in the axial direction, arranged on the rear end side of the first case;
A cylindrical connecting member disposed between the first and second cases and connecting the first and second cases, wherein the connecting member has elasticity;
A pressure detecting element housed in the first case for detecting pressure through the bottom;
A pedestal disposed on the rear end side of the pressure detection element and accommodated in the first case and the connection member, the pedestal contacting the pressure detection element;
A circuit unit disposed on the rear end side of the pedestal and accommodated between the second case and the connection member, the circuit unit for processing a detection signal of the pressure detection element The placed substrate, and
An electrical wiring path that is housed in the first case, in the second case, and in the connection member and electrically connects the pressure detection element and the circuit unit; In the pressure sensor,
The electrical wiring path is accommodated in the connection member of the first pedestal wiring path formed at the rear end of the pedestal accommodated in the connection member of the pedestal portion and the portion of the substrate. A first substrate wiring path formed at the tip of the substrate, and a bonding wire for electrically connecting the first pedestal wiring path and the first substrate wiring path;
The pressure sensor, wherein the connection member has a wire opening for forming the bonding wire by wire bonding from the outside of the connection member. The pressure sensor according to claim 1.
The first pedestal wiring path includes a pedestal side pad,
The first substrate wiring path includes a substrate side pad electrically connected to the pedestal side pad by the bonding wire,
The wire opening is a single opening formed at a position where the base-side pad and the substrate-side pad can be seen from the outside of the connection member. The pressure sensor according to claim 2,
The pedestal side pad is formed on a pedestal plane substantially parallel to the axial direction of the outer surface of the pedestal rear end,
The wire opening is formed at a position where the pedestal-side pad and the substrate-side pad are visible when the connection member is viewed from a direction perpendicular to the pedestal plane and passing through the pedestal-side pad. The pressure sensor characterized by the above-mentioned. The pressure sensor according to any one of claims 1 to 3,
A pressure sensor characterized in that a plurality of openings having the same shape including the wire openings are formed in the connection member at substantially constant intervals in the circumferential direction of the connection member.

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