WO2014045735A1

WO2014045735A1 - Pressure sensor and method for manufacture of same

Info

Publication number: WO2014045735A1
Application number: PCT/JP2013/071078
Authority: WO
Inventors: 克之植松
Original assignee: 富士電機株式会社
Priority date: 2012-09-18
Filing date: 2013-08-02
Publication date: 2014-03-27
Also published as: JP2015222175A

Abstract

Provided are a pressure sensor and method for manufacture of same, whereby the process for attaching the pressure sensor to an ECU chassis can be simplified, the pressure responsiveness of a pressure medium flowing through an intake pipe can be improved, and the volume of the container of the ECU chassis can be reduced. A sealant of a soft resin (silicone resin (13)) is applied to a cap (6) constituting a pressure sensor body (500), and cured to affix it to the cap (6). By causing this silicone resin (13) to move in a manner similar to an O-ring or gasket, the process for attaching the pressure sensor (100) to the ECU chassis can be simplified, the pressure responsiveness of the pressure medium flowing through the intake pipe can be improved, and the volume of the container of the ECU chassis can be reduced.

Description

Pressure sensor and manufacturing method thereof

The present invention relates to a pressure sensor and a manufacturing method thereof.

In recent years, pressure sensors have come to be used to measure intake pressure, exhaust pressure, fuel pressure, atmospheric pressure, etc., in order to improve the fuel efficiency of automobile and motorcycle engines and to digitize engine control for the purpose of purifying exhaust gas. I came. In addition, light weight and downsizing of control devices are required, and space is saved for mounting pressure sensors.

9A and 9B are configuration diagrams of a conventional pressure sensor 501. FIG. 9A is a perspective view of the main part of the pressure sensor main body 500, and FIG. It is principal part sectional drawing of the conventional pressure sensor 501 made. This cap 7 with a pressure guiding pipe is an attachment member for a tube necessary for introducing the pressure medium flowing through the intake pipe into the pressure sensor 501. The pressure sensor main body 500 is described in Non-Patent Document 1. Moreover, the pressure medium 40 mentioned later is the gas or liquid of the object which measures a pressure.

The pressure sensor 501 includes a pressure sensor main body 500 and a cap 7 with a pressure guiding pipe that is fixed on the pressure sensor main body 500. The pressure sensor body 500 includes an SMD (Surface Mount Device) surface 1 and a pressure sensor chip 2. The SMD package 1 includes a resin case 1a, an external lead-out terminal 4 (substrate mounting frame) that penetrates and fixes to the resin case 1a, and a cap 6 that is a lid that closes an upper opening of the resin case 1a. A pressure introducing hole 5 for introducing the pressure medium 40 is formed in the center of the cap 6, and the cap 7 with the pressure guiding pipe is fixed to the cap 6 so that the central axis of the pressure introducing hole 5 is aligned with the central axis of the pressure guiding hole 5. Is done.

Further, a chamber 1b (pressure chamber) in which the pressure sensor chip 2 is attached is formed by the inner wall of the resin case 1a and the cap 6. The pressure guiding pipe 7a of the pressure guiding pipe cap 7 is made of, for example, resin or metal.

The pressure sensor chip 2 fixed in the room 1b is electrically connected to the external lead-out terminal 4 through the bonding wire 3. 10A and 10B are configuration diagrams of a conventional pressure sensor 502 different from FIG. 9, in which FIG. 10A is a cross-sectional view of main parts of the pressure sensor 502, and FIG. 10B is a plan view of main parts of the O-ring 12. It is. In the pressure sensor 502, an O-ring 12 (seal material) is added as an attachment member on the cap 6 of the pressure sensor main body 500.

The O-ring 12 as the sealing material is disposed on the cap 6 in order to maintain airtightness between the pressure sensor main body 500 and the lid of the ECU (EngineＥControl Unit) housing. The O-ring 12 may be attached by forming a groove on the surface of the cap 6.

11A and 11B are configuration diagrams of a conventional pressure sensor 503 different from FIG. 10, in which FIG. 11A is a cross-sectional view of a main part of the pressure sensor 503, and FIG. 11B is a perspective view of a main part of the gasket 12 a. . In FIG. 11, instead of the O-ring 12, a gasket 12a is disposed on the flat surface on the cap 6 as an attachment member. The gasket 12 a is a flat doughnut-shaped flat resin, and has an inner diameter larger than the pressure guide hole 5 of the cap 6 and is disposed so as to surround the pressure guide hole 5.

FIG. 12 is a cross-sectional view of a main part in which the

pressure sensors

501, 502, and 503 are attached to the ECU housing 8. FIG. 12 (a) is a diagram of a tube system (pressure sensor 501), and FIG. The figure of a ring system (pressure sensor 502) and the figure (c) are figures of a gasket system (pressure sensor 503).

In FIG. 4A, a gap N is provided between the lid 8b of the ECU casing 8 and the base 7b of the cap 7 with the pressure guiding pipe of the pressure sensor 501, and the pressure sensor 501 is moved from the lid 8b of the ECU casing 8 to the pressure sensor 501. The direct stress is not transmitted.

In FIG. 4B, an O-ring 12 is sandwiched between the pressure sensor main body 500 and the lid 8b of the ECU housing 8, and these are brought into close contact with each other and fixed with screws 25 or the like. At this time, the respective center axes of the pressure guiding hole 5 of the cap 6, the O-ring 12 and the pressure guiding hole 8c of the lid 8b are aligned.

(C), the gasket 12a is sandwiched between the pressure sensor main body 500 and the lid 8b of the ECU housing 8, and these are brought into close contact with each other and fixed with screws 25 or the like. At this time, the respective center axes of the pressure guiding hole 5 of the cap 6, the gasket 12a, and the pressure guiding hole 8c of the lid 8b are aligned.

FIG. 13 is a diagram in which the ECU housing 8 incorporating

pressure sensors

501, 502, and 503 is attached to the intake pipe 30. FIG. 13 (a) is a diagram of a tube system (pressure sensor 501), and FIG. Is a diagram of an O-ring system (pressure sensor 502), and FIG. 10C is a diagram of a gasket system (pressure sensor 503). The intake pipe 30 through which the pressure medium 40 flows is one of the fluid pipes. This fluid pipe is a pipe through which gas or liquid flows.

In FIG. 2A, when the intake pipe 30 and the ECU casing 8 are separated without being in close contact with each other, the ECU casing 8 is fixed to an external casing 35 such as an engine and the pressure of the intake pipe 30 is guided. The pipe 30 a and the pressure guiding pipe 7 a of the pressure sensor 501 are connected by a tube 9. The pressure medium 40 of the intake pipe 30 is a pressure composed of a pressure introduction hole 30 b of the intake pipe 30, a pressure introduction pipe 30 a, a tube 9, a pressure introduction pipe 7 a of the pressure sensor 501, and a pressure introduction hole 5 of the cap 6 of the pressure sensor body 500. Through the introduction path 21a, the pressure sensor chip 2 is introduced into the fixed room 1b. Since the length of the tube 9 is long, the pressure introduction path 21a becomes long. Although the figure shows a case where the pressure guide pipe 30a and the pressure guide hole 5 are opposed to each other, the tube 9 is usually long and the internal volume of the pressure introduction path 21a is large.

In FIG. 2B, the O-ring 31 is sandwiched between the intake pipe 30 and the ECU casing 8 so that the intake pipe 30 and the ECU casing 8 are firmly fixed, and the O-ring 31 ensures airtightness. The O-ring 31 has a recess 30d formed in the intake pipe 30 and is fixed therein. When the intake pipe 30 and the ECU casing 8 are screwed (25), the O-ring 31 is compressed, and the surface of the intake pipe 30 and the surface of the lid 8b of the ECU casing 8 are fixed in close contact. The pressure medium 40 of the intake pipe 31 includes an O-ring 12 that constitutes a pressure guide hole 30 b of the intake pipe 30, a pressure guide hole 30 c of the intake pipe 30, a pressure guide hole 8 c of the lid 8 b of the ECU housing 8, and a pressure sensor 502. The pressure sensor chip 2 is introduced into the chamber 1b in which the pressure sensor chip 2 is fixed through the pressure introduction path 21b including the pressure introducing hole 5 of the cap 6 of the pressure sensor body 500. The length of the pressure introduction path 21b is greatly shortened compared to the length of the tube system.

In FIG. 2C, the intake pipe 30 and the ECU casing 8 are fixed tightly with an O-ring 31 sandwiched between the intake pipe 30 and the ECU casing 8. The pressure medium 40 of the intake pipe 30 includes the pressure guide pipe 30a of the intake pipe 30, the pressure guide hole 8c of the lid 8b of the ECU housing 8, the gasket 12a constituting the pressure sensor 503, and the pressure of the cap 6 of the pressure sensor body 500. The pressure sensor chip 2 is introduced into the room 1b in which the pressure sensor chip 2 is fixed through the pressure introduction path 21c including the holes 5. The pressure introduction path 21 c is slightly shorter than the O-ring 12 because the thickness of the gasket 12 a is somewhat smaller than the cross-sectional diameter of the O-ring 12.

Patent Documents

1 and 2 describe a structure in which an annular elastic member such as an O-ring is disposed in a groove provided in a flow path. Patent Document 3 describes that a groove is formed in a pressure sensor installed in a flow path, and an O-ring is disposed in the groove.

JP-A-8-35896 JP 2007-212199 A JP 2005-156307 A

In the tube method (pressure sensor 501), the length of the pressure introduction path 21a from the intake pipe 30 through the tube 9 to the pressure introducing hole 5 of the cap 6 of the pressure sensor body 500 is increased, and the pressure introduction path 21a is increased. The internal volume of becomes large. When the internal volume increases, the pressure responsiveness of the pressure medium 40 becomes slow, causing a problem in engine control. In addition, the tube method has a problem that the manufacturing cost increases due to the material cost of the tube 9 and the number of steps for attaching the tube.

Further, from the tip 7b of the pressure guide pipe 7a of the pressure sensor 501 on the resin case 1a side to the tip portion 4a (the L-shaped bottom) of the pressure sensor body 500 on the side not contacting the resin case 1a of the external lead-out terminal 4. There is a problem that the distance M is increased and the outer dimensions of the pressure sensor 501 are increased.

Further, a gap N is provided between the lid 8b of the ECU casing 8 and the base 7b of the cap 7 with the pressure guiding pipe of the pressure sensor 501, and the stress applied to the lid 8b of the ECU casing 8 is directly applied to the pressure sensor 501. I try not to propagate it. Therefore, there is a problem in that the distance P from the lid 8b of the ECU housing 8 to the distal end portion 4a of the external lead-out terminal 4 of the pressure sensor main body 500 increases, and the internal volume Q of the container 8a of the ECU housing 8 increases.

When the O-ring 12 or the gasket 12a is sandwiched between the pressure sensor main body 500 and the lid 8b of the ECU housing 8 and fixed in close contact with the O-ring, the pressure guide hole 5 of the cap 6 and the O-ring are fixed. 12 (or gasket 12a) and the central axis (three central axes) of the pressure guide hole 8c of the lid 8b must be aligned, and the assembly process when the pressure sensor 502 (503) is incorporated in the ECU housing 8 is complicated. There is a problem of becoming.

Also, when the dimensions of the pressure guide hole 5 of the cap 6 change, it is necessary to change the inner diameter of the O-ring 12 (or gasket 12a) accordingly. For this reason, it is necessary to select an O-ring (or gasket 12a) at the time of attachment, and there is a problem that the attachment process becomes complicated.

When the pressure sensor 502 (503) is directly attached to the tubular intake pipe 30, it is necessary to flatten the surface of the intake pipe 30 with which the O-ring 12 (or the gasket 12a) directly contacts, and flat processing is required. There is a problem of becoming.

The object of the present invention is to solve the above-mentioned problems, simplify the process of attaching the pressure sensor to the ECU casing, improve the pressure responsiveness of the pressure medium flowing through the intake pipe, and reduce the volume of the container of the ECU casing. A pressure sensor that can be provided and a method of manufacturing the same are provided.

In order to solve the above-described problems and achieve the object, the pressure sensor according to the present invention has the following characteristics. In the pressure sensor for measuring the pressure of the medium, the pressure sensor includes a soft resin that surrounds a pressure guide hole formed in the package of the pressure sensor and is fixed to the package.

The pressure sensor according to the present invention is characterized in that, in the above-described invention, the soft resin is any one of a silicone resin, a fluorine resin, and a urethane resin.

Further, the pressure sensor according to the present invention is characterized in that, in the above-described invention, the package is a surface mount type.

According to the pressure sensor manufacturing method of the present invention, in the pressure sensor manufacturing method according to the above-described invention, a liquid or semi-liquid soft resin is applied around the pressure guide hole formed in the package on the package. And a step of curing the liquid or semi-liquid soft resin to fix the solidified soft resin to the package.

In the pressure sensor manufacturing method according to the present invention, in the above-described invention, the liquid or semi-liquid soft resin is laterally formed on the surface of the package around the pressure guide hole and on the outer periphery of the package surface. A ring-shaped jig for preventing spread is disposed on the surface of the package, and then the liquid or semi-liquid soft resin is applied to a portion surrounded by the ring-shaped jig on the package. .

The pressure sensor manufacturing method according to the present invention is characterized in that, in the above-described invention, the liquid or semi-liquid soft resin is cured by heating, normal temperature or ultraviolet rays.

According to the present invention, a soft resin sealing material is applied to the cap constituting the pressure sensor main body, cured and fixed to the cap, and the soft resin functions like an O-ring or a gasket, thereby making the ECU housing. It is possible to provide a pressure sensor capable of simplifying the process of attaching the pressure sensor to the body, improving the pressure responsiveness of the pressure medium flowing through the intake pipe, and reducing the volume of the container of the ECU housing, and a method for manufacturing the same. .

BRIEF DESCRIPTION OF THE DRAWINGS It is a block diagram of the pressure sensor 100 which concerns on Example 1 of this invention, (a) is a principal part top view, (b) is principal part sectional drawing cut | disconnected by the XX line of (a). 3 is a cross-sectional view of a main part in which a pressure sensor 100 is attached to the bottom of a container 8a of an ECU housing 8. FIG. FIG. 3 is a view in which an ECU housing 8 with a built-in pressure sensor 100 is closely fixed to an intake pipe 30. It is a diagram comparing the mounting height of the product of the present invention and the conventional product, (a) is a diagram of the tube method (conventional product), (b) is a diagram of the O-ring method (conventional product), (c) is a soft It is a figure of the resin system (this invention product). It is the figure which showed the relationship between the internal volume of the pressure introduction path | route 21, and pressure responsiveness. FIG. 6 is a view showing a method for manufacturing a pressure sensor 100 according to Embodiment 2 of the present invention, and (a) to (d) are cross-sectional views showing a main part manufacturing process shown in the order of processes. FIG. 6 is a diagram for explaining a method of attaching the pressure sensor 100 to the ECU housing 8, and (a) to (d) are cross-sectional views of the main part shown in the order of the attachment process. 3 is a diagram illustrating a method of attaching an ECU housing 8 to an intake pipe 30. FIG. FIG. 4 is a configuration diagram of a conventional pressure sensor 501, (a) is a perspective view of a main part of the pressure sensor main body 500, and (b) is a main part of the conventional pressure sensor 501 in which a cap 7 with a pressure guiding pipe is added to the pressure sensor main body 500. FIG. FIG. 10 is a configuration diagram of a conventional pressure sensor 502 different from FIG. 9, (a) is a cross-sectional view of the main part of the pressure sensor 502, and (b) is a plan view of the main part of the O-ring 12. FIG. 11 is a configuration diagram of a conventional pressure sensor 503 different from FIG. 10, (a) is a cross-sectional view of main parts of the pressure sensor 503, and (b) is a perspective view of main parts of a gasket 12 a. FIG. 4 is a cross-sectional view of a main part in which

pressure sensors

501, 502, and 503 are attached to an ECU housing 8, (a) is a diagram of a tube method (pressure sensor 501), and (b) is an O-ring method (pressure sensor 502). (C) is a diagram of a gasket system (pressure sensor 503). 2A and 2B are diagrams in which an ECU housing 8 incorporating

pressure sensors

501, 502, and 503 is attached to the intake pipe 30, (a) is a diagram of a tube system (pressure sensor 501), and (b) is an O-ring system (pressure sensor) Fig. 502) is a diagram of a gasket system (pressure sensor 503).

Embodiments will be described in the following examples. The same parts as those in the prior art are denoted by the same reference numerals.

<Example 1>
FIGS. 1A and 1B are configuration diagrams of a pressure sensor 100 according to Embodiment 1 of the present invention. FIG. 1A is a plan view of an essential part, and FIG. 1B is a sectional view taken along line XX in FIG. FIG. In FIG. 2B, the inside of the pressure sensor main body 500 is schematically indicated by a dotted line. The pressure sensor body 500 is described in Non-Patent Document 1 as a pressure sensor for atmospheric pressure. However, the present invention is not limited to this, and can be applied to any pressure sensor.

The pressure sensor 100 is composed of a pressure sensor main body 500 and a silicone resin 13 that is a soft resin that is fixedly attached to the pressure sensor main body 500. This silicone resin 13 is used as a shielding material, and is an attachment member fixed on the cap 6 of the pressure sensor main body 500.

As described with reference to FIG. 9A, the pressure sensor main body 500 includes the SMD package 1 and the pressure sensor chip 2. The SMD package 1 includes a resin case 1a, an external lead-out terminal 4, and a cap 6. By using the SMD package 1 for the pressure sensor 100 of the present invention, the external dimensions of the pressure sensor can be reduced.

Also, the cap 6 may be provided with convex portions (not shown) around the pressure guiding hole 5 and on the outer peripheral portion. This convex portion functions as a stopper (liquid reservoir) that prevents the liquid silicone resin 13 from spreading in the lateral direction. In this case, the solidified silicone resin 13 is fixedly disposed at a location surrounded by the convex portions. In some cases, the groove of the concave portion functions as a stopper (liquid reservoir) instead of the convex portion.

Examples of the soft resin include a fluorine-based resin and a urethane-based resin in addition to the silicone resin (the silicone resin 13). These soft resins are resins having excellent elasticity such as rubber. When expressed as hardness as an index of elasticity of the soft resin, it is preferably about 20 to 70, for example, by applying Japan Industrial Association Standard JIS K6253 (Type A durometer). The silicone resin 13 functions in the same manner as the conventional O-ring 12 and gasket 12a.

FIG. 2 is a cross-sectional view of the main part in which the pressure sensor 100 is attached to the bottom of the container 8a of the ECU casing 8. As shown in FIG. The ECU housing 8 includes a container 8a and a lid 8b, and a pressure guide hole 8c is formed in the center of the lid 8b. An ECU board 10 (for example, a printed board) on which electronic components and the pressure sensor 100 are mounted is fixed with screws 25 inside the container 8 a of the ECU housing 8. The distal end portion 4a of the external lead-out terminal 4 of the pressure sensor 100 is fixed to the ECU board 10 with, for example, solder. The lid 8b is put on the pressure sensor 100, and the lid 8b and the container 8a are fastened with, for example, screws 25, and a compressive force is applied to the silicone resin 13 fixed on the cap 6. Accordingly, the lid 8b is brought into close contact with the silicone resin 13 to ensure airtightness, and the lid 8b and the container 8a are fixed. At this time, the respective center axes of the pressure guiding holes 8c formed in the lid 8b and the pressure guiding holes 5 formed in the cap 6 are aligned.

FIG. 3 is a diagram in which the ECU casing 8 having the pressure sensor 100 built in the intake pipe 30 is fixedly fixed. An O-ring 31 is sandwiched between the intake pipe 30 and the lid 8 b of the ECU housing 8, and each is fixed in close contact with, for example, a screw 25. The pressure medium 40 of the intake pipe 30 is a pressure introduction composed of a pressure introduction hole 30 b of the intake pipe 30, a pressure introduction hole 8 c of the lid 8 b of the ECU housing 8, an opening 13 b of the silicone resin 13, and a pressure introduction hole 5 of the cap 6. The pressure sensor chip 2 is introduced into the room 1b in which the pressure sensor chip 2 is fixed via the path 21.

4A and 4B are diagrams comparing the mounting heights of the product of the present invention and a conventional product. FIG. 4A is a diagram of a tube method (conventional product), and FIG. 4B is an O-ring method (conventional product). FIG. 6C is a diagram of the soft resin system (product of the present invention). When the mounting height of the tube method is h1, the mounting height of the O-ring method is h2, and the mounting height of the soft resin method is h3, h3 <h2 <h1. Here, the mounting heights h1 to h3 indicate the height from the front surface 10a of the ECU board 10 to the back surface 8e of the lid 8b. As a specific example, h3 = about 4.5 mm, h2 = about 5.0 mm, and h1 = about 6.5 mm.

In the case of the soft resin system of the present invention, the mounting height h3 is lower than the effective heights h1 and h2 of the conventional product, so that the volume of the container 8a of the ECU casing 8 is reduced, and the ECU casing 8 is small. Can contribute to weight reduction.

Also, in the case of the O-ring method, when a concave groove is formed in the cap 6 and the O-ring is fixed by this groove, the mounting height is slightly lower than h2. However, since the cap 6 is thin, a concave groove cannot be formed deeply, so that h2 is higher than h3.

Further, in the soft resin system of the present invention, the distance between the intake pipe 30 and the pressure guide hole 5 of the cap 6 of the pressure sensor 500 can be significantly shortened compared to the tube system, so the internal volume of the pressure introduction path 21 is reduced to the tube. It can be significantly smaller than the method.

FIG. 5 is a diagram showing the relationship between the internal volume of the pressure introduction path 21 and the pressure responsiveness. This figure also shows a conventional one for reference. The pressure introduction path 21 is a path from the pressure guiding hole 30b of the intake pipe 30 to the surface of the cap 6 (pressure guiding hole 5). The intake pipe 30 is a pipe or the like through which the pressure medium 40 flows, and its wall thickness is usually about several mm to 1 cm. In contrast to the tube method, the soft resin method can significantly reduce the internal volume of the pressure introduction path 21, and thus the pressure response is greatly improved.

Further, in the pressure sensor 100 of the present invention, the silicone resin 13 as a sealing material is fixed to the pressure sensor main body 500. This makes it easier to align the pressure guiding hole 8c of the lid 8b of the ECU housing 8 and the pressure guiding hole 5 of the cap 6 than the O-ring method or the gasket method, and can simplify the assembly process. .

Further, since the pressure sensor 100 of the present invention uses the silicone resin 13 obtained by curing the liquid silicone resin 13a as a sealing material, the planar shape of the pressure guide hole 5 of the cap 6 can easily correspond to any shape. it can. When the pressure sensor 100 is directly attached to the tubular intake pipe 30 (pipe), it is preferable that the surface of the silicone resin 13 has a curvature in advance so as to match the tubular curvature. In order to give curvature to the surface of the silicone resin 13, for example, when a liquid silicone resin 13a is cured, a mold having a curvature can be easily realized. In this way, the curvature of the surface of the silicone resin 13 makes it unnecessary to flatten the intake pipe 30.

<Example 2>
FIG. 6 is a view showing a manufacturing method of the pressure sensor 100 according to the second embodiment of the present invention, and FIGS. 6A to 6D are cross-sectional views of the main part manufacturing process shown in the order of steps. Here, the silicone resin 13 is taken as an example of the sealing material. The sealing material is not limited to the silicone resin 13 and may be a fluorine resin or a urethane resin.

First, in FIG. 2A, the pressure sensor main body 500 is placed on the support base 41, and the liquid silicone resin 13 a does not spread on the outer periphery of the pressure introducing hole 5 or the cap 6 on the cap 6 of the pressure sensor main body 500. For this purpose, a ring-shaped jig 42 is placed. This jig includes a first ring 42a disposed around the pressure introducing hole 5 and a second ring 42b disposed on the outer peripheral portion. A groove for positioning the ring 42 may be formed in the cap 6.

Next, in FIG. 4B, a liquid silicone resin 13a, which is a soft resin, is applied to the cap 6 sandwiched between the first ring 42a and the second ring 42b using a dispenser 43.

Next, in FIG. 4C, the pressure sensor main body 500 coated with the liquid silicone resin 13a is placed in a thermostatic chamber 44 (which may be a hot plate). The processing conditions in this step are, for example, a temperature of about 120 ° C. and a time of about 1 hour. In this step, the liquid silicone resin 13 a is cured and the solidified silicone resin 13 is fixed to the cap 6. The height of the cured and solidified silicone resin 13 is about 0.5 mm.

Next, in FIG. 4D, the pressure sensor main body 500 to which the silicone resin 13 is fixed is taken out from the thermostatic chamber 44, the ring-shaped jig 42 is removed, and the pressure sensor 100 of the present invention is completed.

In this embodiment, the case where a liquid resin is used as a method for fixing the soft resin on the cap 6 has been described. However, a semi-liquid (viscosity of 15 [Pa · S] or more) resin can also be used. In this case, the ring-shaped jig 42 need not be provided.

Here, as a method of curing the liquid silicone resin 13a, thermosetting is used here, but a method of curing the silicone resin by room temperature curing or UV curing (ultraviolet curing) may be used. When a UV curable silicone resin is used instead of the thermosetting silicone resin 13a, the UV curable silicone resin applied to the pressure sensor body 500 is irradiated with ultraviolet rays to cure the UV curable silicone resin. . Since the curing time (ultraviolet irradiation time) in this case is as short as several seconds, the cost can be reduced by reducing the number of manufacturing steps.

FIG. 7 is a diagram for explaining a method of attaching the pressure sensor 100 to the ECU casing 8, and FIGS. 7A to 7D are cross-sectional views of essential parts shown in the order of the attaching process. In FIG. 2A, the tip 4a of the external lead-out terminal 4 of the pressure sensor 100 is fixed to the ECU board 10 by soldering.

Next, in FIG. 4B, the ECU board 10 on which the pressure sensor 100 is mounted is fixed to the bottom of the container 8a of the ECU casing 8 with screws 25. Next, in FIG. 2C, a lid 8b is placed over the opening of the container 8a of the ECU casing 8. At this time, the central axis of the pressure guiding hole 5 of the cap 6 of the pressure sensor main body 500 and the central axis of the pressure guiding hole 8c of the lid 8b are aligned.

Next, the container 8a and the lid 8b are fixed with screws 25 in FIG. At this time, a compressive force is applied to the silicone resin 13, and the pressure guiding hole 5 of the cap 6 and the pressure guiding hole 8 c of the lid 8 b are surrounded by the silicone resin 13 to ensure airtightness.

In the manufacturing method of the pressure sensor 100 of the present invention, the silicone resin 13 as a sealing material is fixed to the pressure sensor main body 500. Thereby, in the manufacturing method of the pressure sensor 100 of the present invention, the alignment of the pressure guiding hole 8c of the lid 8b of the ECU housing 8 and the pressure guiding hole 5 of the cap 6 is easier than the O-ring method or the gasket method. Thus, the assembly process can be simplified.

FIG. 8 is a diagram for explaining a method of attaching the ECU housing 8 to the intake pipe 30. The lid 8b and the intake pipe 30 are fixed by sandwiching an O-ring 31 between the lid 8b of the ECU housing 8 and the intake pipe 30. As a result, the pressure introduction path 21 including the pressure guiding hole 30 b of the intake pipe 30, the opening 13 b of the silicone resin 13 and the pressure guiding hole 5 of the cap 6 of the pressure sensor main body 500 is opened. This pressure introduction path 21 is significantly shortened compared to the tube system, and its internal volume is significantly reduced. Therefore, the pressure response is greatly improved.

Note that a pressure medium 40 to be measured, such as air taken into the engine, flows through the intake pipe 30. The cap 6 may be attached to the resin case 1a after a soft resin is previously applied to the cap 6 and cured. However, in that case, if there is a soft resin when picking up the cap 6 by adsorbing, it may not be adsorbed well, or the soft resin portion may be scratched or indented, which may affect the airtightness. It is desirable to provide a soft resin after attaching the cap 6 to the resin case 1a.

As described above, the pressure sensor and the manufacturing method thereof according to the present invention are useful for manufacturing a pressure sensor in which the volume of the container of the ECU casing is small.

DESCRIPTION OF SYMBOLS 1 SMD package 1a Resin case 1b Room 2 Pressure sensor chip 3 Bonding wire 4 External lead-out terminal 4a Tip part 5 Pressure introducing hole (cap 6)
6 Cap 7 Cap with pressure guiding pipe 7a Pressure guiding pipe 7b Base 8 ECU housing 8a Container 8b Lid 8c Pressure guiding hole (lid 8b)
9 Tube 10 ECU board 12 O-ring (pressure sensor)
13 Solidified silicone resin 13a

Liquid silicone resin

21, 21a, 21b, 21c Pressure introduction path 25 Screw 30 Intake pipe 30a Induction pipe (intake pipe 30)
30b, 30c Pressure guiding hole (intake pipe 30)
30d recess (intake pipe 30)
31 O-ring (intake pipe 30)
40 Pressure medium 41 Support base 42 Ring-shaped jig 42a First ring 42b Second ring 43 Dispenser 44 Constant temperature bath

Claims

In the pressure sensor that measures the pressure of the medium,
A pressure sensor comprising a soft resin surrounding a pressure guide hole formed in the package of the pressure sensor and fixed to the package.
2. The pressure sensor according to claim 1, wherein the soft resin is any one of a silicone resin, a fluorine resin, and a urethane resin.
The pressure sensor according to claim 1, wherein the package is a surface mount type.
In the manufacturing method of the pressure sensor according to any one of claims 1 to 3,
Applying a liquid or semi-liquid soft resin around the pressure guide holes formed in the package on the package;
Curing the liquid or semi-liquid soft resin and fixing the solidified soft resin to the package;
A method for manufacturing a pressure sensor, comprising:
After disposing a ring-shaped jig on the surface of the package to prevent the liquid or semi-liquid soft resin from spreading in the lateral direction around the pressure guiding hole and on the outer periphery of the package surface. The method for manufacturing a pressure sensor according to claim 4, wherein the liquid or semi-liquid soft resin is applied to a portion surrounded by the ring-shaped jig on the package.
6. The method for producing a pressure sensor according to claim 4, wherein the liquid or semi-liquid soft resin is cured by heating, room temperature or ultraviolet rays.