JP2014211389A - Pressure detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pressure detector that has great heat resistance and earthquake resistance while its structure is simplified and its manufacturing cost is kept low.SOLUTION: A pressure detector comprises: a fluid inflow member 10 having a flow channel in which fluid can be flowed; a terminal holder base member 30 having a lead terminal 32 connected to a pressure sensor 20; a terminal unit cover member 40 outsert-molded to the terminal holder base member 30 while covering the pressure sensor 20 and forming a sealed space; and a lid member 50 that is connected to the terminal unit cover member 40 and the terminal holder base member 30 and that forms the sealed space B inside which the pressure sensor 20 is positioned. The fluid inflow member 10 is formed with a metal-made material 10. The pressure detector can be provided that is prevented from being affected by heat being conducted from the side of a mounting member for mounting and fixing the pressure detector by the fluid inflow member 10 made of the metal-made material and that has great heat resistance and earthquake resistance while its structure is simplified and its manufacturing cost is kept low.

Description

  The present invention relates to a pressure detection device including a semiconductor pressure sensor, and more particularly to a pressure detection device that can be used as a pressure detection device for use in a harsh environment, for example, for a vehicle.

  As a conventional pressure detection device, for example, there is one disclosed in Patent Document 1. In the pressure detection device according to Patent Document 1, the main body of the detection device is formed by a resin case provided with a pressure introduction portion (measurement pressure introduction chamber) for introducing fluid pressure, and the measurement pressure introduction chamber of the main body by this resin case is formed. A pressure-sensitive element (semiconductor pressure sensor) is arranged on the upper side, a connector insertion part is provided when the main body is molded by a resin case, and a plurality of metal terminals extending to the connector insertion part are embedded by insert molding . In addition, the pressure-sensitive element (semiconductor pressure sensor) is electrically connected to the outside by bonding with a wire between the electrode portion and the terminal, and the pressure-sensitive surface that is the front side of the main body by the resin case The upper side of the element is provided so as to be covered and sealed with a lid.

JP 09-043076 A

  By the way, in the pressure detection device in Patent Document 1 configured as described above, although the main body by the resin case is integrally formed with the terminal, there is a merit that the number of parts can be reduced. When used in a rough environment, high heat or vibration is directly transmitted to the pressure introduction part of the main body by the resin case, which has the problem of affecting the main body by the resin case. It was.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a pressure detection device that can eliminate the effects of heat and vibration, which are the problems, and can improve the assembly workability by resin molding.

In order to solve the above-described problems, the present invention provides a fluid inflow member having a flow path through which fluid can flow,
A semiconductor pressure sensor that is provided on the upper surface side of the fluid inflow member and detects the pressure of the fluid flowing into the flow path;
A base resin portion disposed on the upper surface side of the fluid inflow member and having an opening formed so as to surround the semiconductor pressure sensor, and held at the time of molding the base resin portion, and one end thereof is the semiconductor type A terminal holder base member having a lead terminal electrically connected to the pressure sensor;
A terminal unit cover member that is outsert-molded by an outsert molding resin part so that a part of the fluid inflow member and the terminal holder base member is exposed;
A wire connected by wire bonding between the semiconductor pressure sensor and the lead terminal;
A lid member that is coupled to the terminal unit cover member and the terminal holder base member so as to cover the semiconductor pressure sensor from above, and forms a sealed space in which the semiconductor pressure sensor is located;
In the pressure detection device, the fluid inflow member is formed of a metal material.

  With this configuration, the influence of heat transmitted from the mounting member side for mounting and fixing the pressure detection device can be prevented by the metal fluid inflow member, and the terminal holder base member and the terminal unit cover member are made of resin. By forming integrally with the fluid inflow member by molding, it is possible to provide a pressure detection device with high heat resistance while simplifying the structure of the pressure detection device and suppressing the manufacturing cost.

In the present invention, a fluid inflow member having a flow path into which a fluid can flow, a semiconductor pressure sensor provided on an upper surface of the fluid inflow member for detecting the pressure of the fluid flowing into the flow path, and the fluid inflow member The base resin part is disposed on the upper surface side and has an opening formed so as to surround the semiconductor pressure sensor. The base resin part is held when the base resin part is molded, and one end of the base resin part is electrically connected to the semiconductor pressure sensor. A terminal holder base member having an electrically connected lead terminal, and a terminal unit cover member that is outsert-molded by an outsert molding resin portion so that a part of the fluid inflow member and the terminal holder base member are exposed. A wire for connecting the semiconductor pressure sensor and the lead terminal by wire bonding, and the semiconductor pressure sensor A cover member that is coupled to the terminal unit cover member and the terminal holder base member so as to cover the semiconductor, and forms a sealed space in which the semiconductor pressure sensor is located, and the fluid inflow member is made of a metal material. Since the pressure detection device is characterized by being formed by the metal fluid inflow member, deterioration of the influence of heat transmitted from the mounting member side for mounting and fixing the pressure detection device can be prevented. A holder base member and a terminal unit cover member are integrally formed with a fluid inflow member by resin molding, thereby providing a pressure detection device with high heat resistance while simplifying the structure of the pressure detection device and reducing manufacturing costs. This can achieve the intended purpose.
A pressure detection device rich in heat can be provided.

It is sectional drawing which shows the pressure detection apparatus which concerns on embodiment of this invention. FIG. 2 is a cross-sectional view showing a state in which the lid member in the pressure detection device of FIG. 1 is removed. FIG. 3 is a plan view of FIG. FIG. 4 is a plan view showing a terminal holder base member in which the lead terminal in the embodiment of the present invention is insert-molded by the base resin portion. FIG. 5 is a plan view showing a state in which a noise absorbing capacitor is mounted on the lead terminal of the terminal holder base member of FIG. FIG. 6 is a cross-sectional view showing the main part of FIG. FIG. 7 is a cross-sectional view showing a main part of the pressure detecting device showing a state in which a terminal unit cover member is outsert-molded on the terminal holder base member of FIG. FIG. 8 is a plan view of FIG.

  Hereinafter, a first embodiment to which the present invention is applied will be described with reference to the accompanying drawings (FIGS. 1 to 7).

  As shown in FIGS. 1 to 7, the pressure detection device 1 according to the embodiment of the present invention includes a fluid inflow member 10, a semiconductor pressure sensor (hereinafter also simply referred to as a pressure sensor) 20, and a terminal holder base member 30. And a terminal unit cover member 40 having a connector portion, and a lid member that is coupled to the resin portion of the terminal holder base member 30 so as to cover the pressure sensor 20 from above, and forms a sealed space in which the pressure sensor 20 is located. 50.

  The fluid inflow member 10 is made of a metal material such as stainless steel (SUS), and includes a cylindrical body 11 and a groove (recess) 11a provided on the outer periphery of the center of the body. A sealing member R made of a sealing O-ring or the like is fitted into the groove 11a of the fluid inflow member 10, and is provided so as to be kept airtight by the sealing member R with respect to the mounting member to which the pressure detecting device 1 is assembled.

  The fluid inflow member 10 is formed with a flow path 12 that is a hole penetrating in the vertical direction of the body portion 11. The fluid (for example, oil) can flow in into the flow path 12 from the lower side.

  The trunk portion 11 is provided with a pedestal 11b at the periphery of the upper end side of the flow path 12, and the pressure sensor 20 is placed on the pedestal 11b and fixed by a predetermined method such as thermosetting adhesive or solder. Yes. An opening 12a, which is the upper end of the flow path 12, is located at the center of the pedestal 11b.

  The pressure sensor 20 is formed, for example, by disposing a semiconductor chip having a diaphragm formed by thinly forming a semiconductor substrate such as silicon on a glass pedestal. In the part corresponding to the diaphragm, four resistances that become pressure-sensitive elements having a piezoresistance effect are formed by diffusion of impurities such as boron, and wiring using each resistance and a conductive material such as aluminum A bridge circuit is formed in the pressure sensor 20 by the pattern.

  The pressure sensor 20 is provided so that the fluid pressure introduced from the lower side of the flow path 12 is received by the diaphragm, and the fluid pressure is detected by the output voltage of the bridge circuit according to the displacement of the diaphragm.

  The terminal holder base member 30 includes a base resin portion 31 having a substantially plate shape and a plurality of lead terminals 32.

  The base resin portion 31 has a substantially L-shaped cross section, and includes a flat plate portion 31a extending together with a plurality of molded lead terminals 32, and a rising wall portion 31b extending from the flat plate portion 31a in a substantially vertical direction. The noise absorbing capacitor 300 is disposed along the rising wall portion 31b.

  Further, an opening 31c is provided on the right end side of the flat plate portion 31a at a location coaxially with the flow path 12 of the fluid inflow member 10, and the flat plate portion 31a is outsert-molded with respect to the fluid inflow member 10. Thus, the base resin portion 31 and the fluid inflow member 10 are integrally formed, and are provided so that one end portion of the lead terminal 32 faces the opening portion 31c.

  The lead terminals 32 are made of, for example, a phosphor bronze material, and there are three lead terminals 32 as shown in the figure. Each of the lead terminals 32 is assigned as a power line 321, a signal line 322, and a ground line 323.

  The surface of the lead terminal 32 is plated with nickel so that the connection reliability of the wire W by wire bonding can be improved. One end portion of the lead terminal 32 is located in the vicinity of the pressure sensor 20, while the lead terminal 32 portion of the other end portion is drawn out and guided to the outside of the base resin portion 31, and a terminal unit cover provided with a connector portion described in detail later. It is provided so as to be positioned inside the female connector portion formed on the member 40.

  One end of the lead terminal 32 is connected to the pressure sensor 20 by a wire W made of, for example, aluminum. For the connection of the wire W, a wire bonding apparatus is used.

  It should be noted that the contact portion between the base resin portion 31 and the lead terminal 32 of the terminal holder base member 30 is subjected to an impregnation process which is a process of filling a seal material into a gap generated during insert molding.

  The lead terminal 32 includes a lead frame 320 integrally provided with a plurality of lead terminals 32 (321, 322, 323) for power supply, output, and ground when insert molding is performed by the base resin portion 31. After the insert molding of the part 31, the connecting part 320a provided on the lead frame 320 is cut into individual lead terminals 32 (321, 322, 323) and lead terminals 32 (321 obtained at the time of cutting). , 322, 323), the wire W is connected to the wire connecting portion 32a provided at the end portion by wire bonding.

  At this time, the base resin portion 31 is provided with an opening 31c for placing the pressure sensor 20 and a plurality of lead terminals 32 (321, 322) provided on the lead frame 320 at the position of the opening 31c. , 323) is arranged, the connection part 320a of the lead frame 320 located in the opening part 31c can be easily cut after the insert molding of the base resin part 31, and thus manufactured. A plurality of lead terminals 32 (321, 322, 323) that can be connected to the pressure sensor 20 can be obtained without complicating the process.

  The noise absorbing capacitor 300 is made of, for example, a lead-type ceramic capacitor, and includes a capacitor portion 300a and a lead portion 300b bent into an L shape. One of the noise absorbing capacitors 300 is connected between the power line 321 and the ground line 323 of the lead terminal 32, and the other noise absorbing capacitor 300 is connected to each lead of the signal line 322 and the ground line 323. It is connected between the terminals 32 and absorbs the superimposed external noise. The capacitor part 300a is disposed along a position adjacent to the rising wall part 31b of the terminal holder base member 30, and the lead part 300b is connected to a predetermined part of the lead terminal 32 by means such as resistance welding.

  The terminal unit cover member 40 exposes a part of the fluid inflow member 10, a connection portion of the wire W that is one end side of the lead portion 32, and the other end side of the lead portion 32, and most of the terminal holder base member 30. And the outsert molding resin part 41 that covers the noise absorbing capacitor 300 by injection molding. (The terminal unit cover member 40 is outsert molded with respect to the terminal holder base member 30 and the fluid inflow member 10. )

  Further, the outsert molding resin portion 41 of the terminal unit cover member 40 has an opening portion 41a where the upper portion of the pressure sensor 20 opens, and a peripheral portion of the opening portion 41a is a step for disposing the lid member 50. The female part which couple | bonds with the male connector part (not shown) for connecting the power supply line 321, the signal line 322, and the ground line 323 to this lead terminal 32 while the part 41b and the other end of the lead terminal 32 are exposed. Connector part 41c. The lead terminal 32 is subjected to a surface treatment in which the surface thereof is finely roughened, and the air tightness of the interface between the terminal unit cover member 40 and the terminal holder base member 30 is ensured satisfactorily. The fluid inflow member 10 is also subjected to the same surface treatment to ensure good airtightness at the interface between the inflow member 10 and the terminal unit cover member 40.

  The terminal unit cover member 40 is a female type that opens in a direction orthogonal to the flow path 12 of the fluid inflow member 10 in a shape after being outsert-molded with respect to the terminal holder base member 30 and the fluid inflow member 10. A connector portion 41c is provided, and an abutting rib 41d is formed so as to follow the flat surface from the lower end surface of the female connector portion 41c to the surface reaching the fluid introduction portion 10. In this way, in the casing configuration that extends in the width direction by forming the abutting rib 41d having the flat surface at the lower end side of the terminal unit cover member 40, there is no backlash in assembling to the attached portion (attachment member). It can prevent well.

  The lid member 50 is made of, for example, PPS resin, and is coupled to the stepped portion 41b of the terminal unit cover member 40 by means such as laser welding so as to cover the pressure sensor 20 from above, and the pressure sensor 20 is sealed inside. It is a member that forms a space.

  The inner surface of the lid member 50 has a concave shape, and a pressure reference chamber B serving as a sealed space is formed between the lid member 50 and the base resin portion 31.

  The lid member 50 is laser welded to the step portion 41b of the outsert molding resin portion 41. Even if the lid member 50 is joined to the base resin portion 31 of the terminal holder base member 30 by laser welding, the same applies. A simple pressure reference chamber B can be configured.

  The pressure detection device 1 is configured by the above-described units.

  The structure of the pressure detection device 1 is a structure that is easy to assemble and can suppress an increase in the number of parts and the number of man-hours. A method for manufacturing the pressure detection device 1 will be described.

  First, a plurality of lead terminals 32 (321, 322, 323) connected by the connecting portion 320a are set in a mold, a resin material made of the base resin portion 31 is injected, and terminals are formed by insert molding using the resin material. The holder base member 30 is formed. (See Figure 4)

  Next, before the terminal unit cover member 40 is molded, the connecting portion 320a provided in the lead frame 320 that is insert-molded as a pre-treatment is cut, and the individual (three) lead terminals 32 (321, 322, 323), and one of the noise absorbing capacitors 300 is connected between the power supply line 321 and the ground line 323 of the lead terminal 32, and the other noise absorbing capacitor 300 is connected to the signal line 322 and the ground. A connection is made between each lead terminal 32 and the line 323. (See FIGS. 5 and 6)

  Then, the terminal holder base member 30 integrally formed with the lead terminals 32 is set on the mold in a state where the lead holder 32 is disposed on the fluid inflow member 10, and the resin material including the outsert molding resin portion 41 is injected into the mold. Then, the terminal unit cover member 40 is formed. (See FIGS. 7 and 8)

  Next, as shown in FIGS. 2 and 3, after the terminal unit cover member 40 is molded, the pressure sensor 20 is placed on the base 11b of the fluid inflow member 1 and fixed and held in place with a thermosetting adhesive or the like. Then, the pressure sensor 20 and the lead terminals 32 (321, 322, 323) are conductively connected by the wire W using a wire bonding apparatus.

Then, as shown in FIG. 1, a lid member 50 that covers the upper side of the pressure sensor 20 is joined to the step portion 41 b of the terminal unit cover member 40 by laser welding to form an airtight space B of the pressure sensor 20.
The pressure detection device 1 is formed through the above steps.

  As described above, the pressure detection device 1 according to the present embodiment is provided on the upper surface of the fluid inflow member 10 having the flow path 12 into which the fluid can flow, and detects the pressure of the fluid flowing into the flow path 12. A semiconductor pressure sensor 20 that is disposed on the upper surface side of the fluid inflow member 10, and a base resin portion 31 that is provided with an opening 31 c so as to surround the semiconductor pressure sensor 20, and is held when the base resin portion 31 is molded. In addition, a terminal holder base member 30 having a lead terminal 32 electrically connected to the semiconductor pressure sensor 20 at one end thereof, and a part of the fluid inflow member 10 and the terminal holder base member 30 are exposed. A terminal unit cover member 40 that is outsert-molded by the outsert molding resin portion 41, the semiconductor pressure sensor 20 and the lead terminal 32 Are connected to the wire W connected by wire bonding and the terminal unit cover member 40 and the terminal holder base member 30 so as to cover the semiconductor pressure sensor 20 from above, and the sealed space in which the semiconductor pressure sensor 20 is located. And the fluid inflow member 10 is made of a metal material, so that the influence of heat transmitted from the attachment member side to which the pressure detection device 1 is attached and fixed is made of metal. Deterioration can be prevented by the fluid inflow member 10, and the pressure detection device 1 rich in heat resistance and earthquake resistance can be provided.

  The lead terminal 32 includes a lead frame 320 integrally provided with a plurality of lead terminals 32 (321, 322, 323) for power supply, output, and ground when insert molding is performed by the base resin portion 31. The frame 320 is formed by disposing a connecting portion 320a where a plurality of lead terminals 321, 322, 323 are connected at the opening 31c, thereby cutting the connecting portion 320a provided on the lead frame 320 after the insert molding of the base resin portion 31. The lead terminals 32 (321, 322, 323) are separated individually, and wires are connected to the wire connecting portions 32a provided at the ends of the lead terminals 32 (321, 322, 323) obtained at the time of cutting. W can be connected. At this time, since a plurality of lead terminals 321, 322, and 323 can be set in the mold in an integrated state via the connecting portion 320 a during molding by the mold, the structure is simplified and the manufacturing cost is reduced. It becomes possible to suppress. Further, the base resin part 31 is provided with an opening 31c for placing the semiconductor pressure sensor 20, and the connecting part 320a of the lead frame 320 located in the opening 31c can be easily cut, so that the manufacturing process is complicated. Without this, a plurality of lead terminals 32 (321, 322, 323) that can be connected to the semiconductor pressure sensor 20 can be obtained.

  The noise absorbing capacitor 300 is connected to the power supply line 321 and the signal line 322 of the lead terminal 32 and absorbs the superimposed external noise. The noise absorbing capacitor 300 is an outsert molding of the terminal unit cover member 40. The resin portion 40a covers and protects most of the terminal holder base member 30 by injection molding. At this time, at the time of outsert molding of the terminal holder base member 30, a location where the noise absorbing capacitor 300 is adjacent along the rising wall portion 31b which is a protective wall extending substantially vertically from the flat plate portion 31a of the base resin portion 31. Therefore, when the resin of the base resin portion 31 which is a molding material melted from the gate port of the mold flows in, the flow is hindered by the rising wall portion 31b which is a protective wall, and the noise absorbing capacitor The flow speed is reduced before the contact with 300, and the resistance force acting on the noise absorbing capacitor 300 is reduced, which makes it possible to prevent the noise absorbing capacitor 300 from being damaged.

  In addition, this invention is not limited by the above embodiment and drawing. Changes (including deletion of constituent elements) can be added to the embodiments and the drawings as appropriate without departing from the scope of the present invention.

  Further, in the above-described embodiments, the pressure detection device for a vehicle or the like has been described as an example of the application, but the present invention is not limited to the vehicle but is also applied to a special vehicle such as a ship or an agricultural machine or a construction machine. Of course, the present invention can be applied to various pressure detection devices other than vehicles.

DESCRIPTION OF SYMBOLS 1 Pressure detection apparatus 10 Fluid inflow member 11 Trunk part 11a Groove part (concave part)
11b Pedestal 12 Flow path 12a Opening 20 Semiconductor pressure sensor 30 Terminal holder base member 31 Base resin part 31a Flat plate part 31b Rising wall part (protective wall)
31c Opening portion 32 Lead terminal 32a Wire connection portion 40 Terminal unit cover member 41 Outsert molding resin portion 41a Opening portion 41b Step portion 41c Female connector portion 41d Abutting rib 50 Lid member portion 300 Noise absorbing capacitor 320 Lead frame 320a connection 321 Power supply line (lead terminal)
322 Signal line (lead terminal)
323 Ground line (Lead terminal)
B Pressure reference chamber (sealed space)
R Seal member W Wire

Claims (1)

A fluid inflow member having a flow path through which a fluid can flow; and
A semiconductor pressure sensor that is provided on the upper surface of the fluid inflow member and detects the pressure of the fluid flowing into the flow path;
A base resin portion disposed on the upper surface side of the fluid inflow member and provided with an opening so as to surround the semiconductor pressure sensor, and held at the time of molding the base resin portion, and one end portion of the base resin portion is the semiconductor type A terminal holder base member having a lead terminal electrically connected to the pressure sensor;
A terminal unit cover member that is outsert-molded by an outsert molding resin part so that a part of the fluid inflow member and the terminal holder base member is exposed;
A wire connected by wire bonding between the semiconductor pressure sensor and the lead terminal;
A lid member that is coupled to the terminal unit cover member and the terminal holder base member so as to cover the semiconductor pressure sensor from above, and forms a sealed space in which the semiconductor pressure sensor is located;
The pressure detecting device, wherein the fluid inflow member is formed of a metal material.

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