JP2015219174A - Pressure sensor packaging structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To determine whether a pressure sensor falls from a mounted member.SOLUTION: A pressure sensor comprises: temperature adjustment means 7 that changes a temperature of a space 3a of a mounted member 3; detection means 22 that outputs a detection signal corresponding to a state of the space 3a of the mounted member 3; and determination means 9 and 23 that determine whether one end of a port part 12 is inserted into the mounted member 3 on the basis of the detection signal.

Description

  The present invention relates to a mounting structure of a pressure sensor that is attached to a mounted member having a space inside and detects the pressure in the space of the mounted member.

  2. Description of the Related Art Conventionally, a collision detection device has been proposed in which a pressure sensor including a pressure detection element that outputs a sensor signal corresponding to pressure is mounted on a mounted member in which a space is formed (for example, Patent Document 1). reference).

  Specifically, in this collision detection device, an opening is formed in the attached member. And a pressure sensor is fixed to the opening part of a to-be-attached member, and outputs the sensor signal according to the pressure of the space of a to-be-attached member to an external circuit. For this reason, in an external circuit, various processes are performed based on the sensor signal according to the pressure of the space of a to-be-attached member.

JP 2010-69978 A

  However, since the pressure sensor outputs a sensor signal corresponding to the pressure, the sensor outputs a sensor signal corresponding to the ambient pressure when the pressure sensor falls off the attached member. And the said collision detection apparatus cannot grasp | ascertain the fixed state of a pressure sensor. For this reason, in the external circuit, even when the pressure sensor is detached from the member to be attached, a sensor signal corresponding to the ambient pressure is output from the pressure sensor, which may cause erroneous processing.

  An object of this invention is to provide the pressure sensor which can determine whether it fell out from the to-be-attached member in view of the said point.

  In order to achieve the above object, according to the first aspect of the present invention, a pressure detection element (22) that outputs a sensor signal corresponding to pressure, a main body (11) on which the pressure detection element is mounted, and a connection to the main body. And a case (10) having a port portion (12) in which a pressure introduction hole (15) for introducing pressure into the pressure detection element is formed, forming a space (3a) inside and opening an opening portion. In the mounting structure of the pressure sensor for detecting the pressure in the space of the mounted member, one end of the port portion opposite to the main body is inserted into the opening of the mounted member (3) having the following features. .

  That is, the temperature adjustment means (7) for changing the temperature of the space of the attached member, the detection means (22) for outputting a detection signal corresponding to the state of the space of the attached member, and the port portion based on the detection signal And determining means (9, 23) for determining whether or not one end is inserted into the attached member.

  According to this, it can be determined by the determination means whether the one end part of the port part is inserted in the to-be-attached member. For this reason, it can suppress that an external circuit performs a wrong process based on a sensor signal.

  In addition, the code | symbol in the bracket | parenthesis of each means described in this column and the claim shows the correspondence with the specific means as described in embodiment mentioned later.

It is a plane schematic diagram when the collision detection apparatus in 1st Embodiment of this invention is arrange | positioned in the bumper of a vehicle. It is sectional drawing along the II-II line | wire in FIG. It is sectional drawing of the pressure sensor and tube shown in FIG. It is sectional drawing of the pressure sensor and tube in 2nd Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, parts that are the same or equivalent to each other will be described with the same reference numerals.

(First embodiment)
A first embodiment of the present invention will be described. In the present embodiment, an example will be described in which the pressure sensor of the present invention is mounted (attached) on a mounted member to constitute a collision detection device, and the collision detection device is mounted on a vehicle.

  As shown in FIG. 1, the collision detection device 1 of the present embodiment includes two pressure sensors 2 and a tube 3 as a member to be attached to which the pressure sensor 2 is attached. And it is arrange | positioned in the bumper 8 with the reinforcement 4, the side member 5, the absorber 6, the cooling piping 7, etc. FIG. Each pressure sensor 2 is connected to an ECU (Engine Control Unit) 9 of the vehicle.

  The reinforcement 4 is a metal member disposed in the bumper 8 and extends in the vehicle width direction (the left-right direction in FIG. 1). The side members 5 are metal members provided at both ends of the reinforcement 4 in the extending direction, and extend in the vehicle front-rear direction (the vertical direction in the drawing in FIG. 1).

  The tube 3 is a member made of a synthetic resin such as polyethylene. The tube 3 forms a space 3a (see FIG. 2) inside and is a cylindrical member having openings at both ends, and extends in the vehicle width direction. Yes. And it is arrange | positioned rather than the reinforcement 4 in the vehicle forward side.

  The absorber 6 is disposed so as to cover the tube 3 and is a member made of a foamed resin member.

  As shown in FIG. 2, the cooling pipe 7 is disposed in a recess 4 a formed in a portion of the reinforcement 4 that faces the tube 3, and cools the space 3 a of the tube 3. In the present embodiment, the cooling pipe 7 corresponds to the temperature adjusting means of the present invention, and is constituted by a pipe or the like for cooling the internal combustion engine.

  The ECU 9 is composed of a microcomputer, peripheral devices, and the like, and is connected to the pressure sensor 2 and disposed on the vehicle body. Based on the pressure detected by the pressure sensor 2, the airbag system and the like are controlled.

  The pressure sensors 2 are fixed to the openings at both ends of the tube 3 one by one and detect the pressure in the space 3 a of the tube 3. Here, the structure of the pressure sensor 2 of this embodiment is demonstrated, referring FIG. Each pressure sensor 2 has the same configuration.

  The pressure sensor 2 includes a case 10 formed by molding a heat insulating resin material or the like. The case 10 includes a main body portion 11 and a port portion 12 connected to the main body portion 11. Yes. A recess 13 and an opening 14 are formed in the main body 11, and a pressure introduction hole 15 that connects the recess 13 and the external space (the space 3 a of the tube 3) is formed in the port 12.

  A sensor unit 20 is disposed in the recess 13 of the case 10. This sensor unit 20 has a first surface 21a and another surface 21b, and a wiring substrate 21 such as a ceramic substrate or a printed circuit board in which the first surface 21a and the other surface 21b are electrically connected via a wiring pattern, a via, or the like. have. A sensor chip 22 and a circuit chip 23 are mounted on one surface 21 a of the wiring board 21. The sensor chip 22 is electrically connected to the circuit chip 23 via the bonding wire 24, and the circuit chip 23 is electrically connected to the wiring substrate 21 via the bonding wire 25. Further, an electronic component 26 such as a capacitor is mounted on the other surface 21b of the wiring board 21 via a conductive adhesive or the like (not shown).

  The sensor chip 22 is formed with a sensing unit that outputs a sensor signal according to pressure and a sensing unit that outputs a detection signal according to temperature. In the present embodiment, the sensing unit that outputs a sensor signal corresponding to pressure is configured using a resistor whose resistance value changes according to pressure, and the sensing unit that outputs a detection signal corresponding to temperature corresponds to the temperature. Accordingly, a resistor whose resistance value changes is used. In the present embodiment, the sensor chip 22 corresponds to the pressure detection element and detection means of the present invention.

  The circuit chip 23 includes a signal processing circuit that performs predetermined processing on the sensor signal and the detection signal, a determination processing circuit that determines the detection signal, and the like. In the present embodiment, the circuit chip 23 corresponds to the determination unit of the present invention, and the circuit chip 23 performs determination for comparing the detection signal with a threshold value.

  A sleeve 27a made by molding a resin material is disposed on one surface 21a of the wiring board 21. Specifically, the sleeve 27 a has a frame shape and is disposed on the one surface 21 a of the wiring substrate 21 so as to surround the sensor chip 22 and the circuit chip 23.

  A protective member 28a is disposed in the space surrounded by the sleeve 27a so that the sensor chip 22, the circuit chip 23, and the bonding wires 24 and 25 are sealed. Although not particularly limited, as the protective member 28a, for example, a material excellent in corrosion resistance, chemical resistance, or the like such as silicone gel or fluorine gel is used.

  The above is the configuration of the sensor unit 20. And this sensor unit 20 is mounted in the bottom face of the recessed part 13 so that the opening part of the pressure introduction hole 15 formed in the bottom face of the recessed part 13 may be obstruct | occluded. Specifically, the sensor unit 20 is configured such that the end of the sleeve 27a opposite to the wiring board 21 is recessed via an adhesive (not shown) so that the one surface 21a of the wiring board 21 faces the bottom surface of the recessed part 13. It is mounted on the bottom surface of the recess 13 by being fixed to the bottom surface of the recess 13.

  The port portion 12 has a substantially cylindrical shape, and one end portion on the side opposite to the main body portion 11 is an insertion portion 16 into which the tube 3 is inserted.

  The insertion portion 16 is formed with a fixing portion 17 at the distal end portion that suppresses the insertion portion 16 (pressure sensor 2) from falling off the tube 3 when the insertion portion 16 is inserted into the tube 3. ing. The fixing portion 17 has a tapered shape with a diameter increasing from the front end side toward the rear end side, the diameter at the front end side is smaller than the inner diameter of the tube 3, and the diameter at the rear end side is the inner diameter of the tube 3. Has been bigger than.

  Further, the case 10 is provided with a metal rod-shaped terminal 31 that electrically connects the circuit chip 23 (wiring board 21) and an external circuit. The terminal 31 is held in the case 10 by being integrally formed with the case 10 by insert molding.

  Specifically, the terminal 31 is held in the case 10 such that one end is exposed in the recess 13 and the other end protrudes into the opening 14. One end of the terminal 31 exposed in the recess 13 is electrically connected to the circuit chip 23 (wiring substrate 21) via the bonding wire 41. The other end of the terminal 31 is electrically connected to an external circuit via an external wiring member (not shown).

  Furthermore, a lid 50 made by molding a resin material so as to close the recess 13 is joined to the case 10 via an adhesive or the like (not shown).

  The above is the configuration of the collision detection apparatus 1. In the collision detection device 1, when a person or a vehicle collides with the bumper 8, the pressure in the space 3 a of the tube 3 changes. Therefore, the ECU 9 basically controls the airbag system and the like based on the sensor signal output from the sensor chip 22.

  The space 3 a of the tube 3 is cooled by the cooling pipe 7, and the space 3 a of the tube 3 has a temperature different from that of the space outside the tube 3. When the insertion portion 16 is inserted into the tube 3 from the sensor chip 22, a detection signal corresponding to the temperature of the space 3 a of the tube 3 is input to the circuit chip 23. When not inserted, a detection signal corresponding to the temperature of the space outside the tube 3 is input.

  For this reason, the circuit chip 23 compares the detection signal with the threshold value to determine whether or not the insertion portion 16 is inserted into the tube 3 and inserts the determination result into the ECU 9. Then, based on the determination result input from the circuit chip 23, the ECU 9 informs the occupant by driving the voice means, the display means, and the like when the port portion 12 is detached from the tube 3. . For example, the sound means can be driven to notify the occupant with an electronic sound. In addition, the display means can be driven to display the occurrence of abnormality on a liquid crystal display disposed in a part of an instrument display panel disposed in front of the steering wheel or in the center of the dashboard to notify the occupant.

  As described above, in the present embodiment, the space 3 a of the tube 3 is cooled by the cooling pipe 7, and the space 3 a of the tube 3 has a temperature different from that of the space outside the tube 3. The circuit chip 23 determines whether or not the port portion 12 is inserted into the tube 3 by comparing the detection signal input from the sensor chip 22 with a threshold value. For this reason, when the port part 12 has fallen off from the tube 3, it can suppress that ECU9 operates an airbag system etc. based on the sensor signal from the sensor chip 22. FIG.

(Second Embodiment)
A second embodiment of the present invention will be described. The present embodiment is provided with a sensor chip that detects the temperature outside the tube 3 with respect to the first embodiment, and the other aspects are the same as those of the first embodiment, and thus the description thereof is omitted here.

  In the present embodiment, as shown in FIG. 4, the sensor chip 29 is disposed on the other surface 21 b of the wiring board 21, and the sensor chip 29 is electrically connected to the wiring board 21 via the bonding wires 30. . The sensor chip 29 is formed with a sensing unit similar to the sensing unit that outputs a sensor signal corresponding to the temperature formed on the sensor chip 22.

  A sleeve 27 b is disposed on the other surface 21 b of the wiring board 21 so as to surround the sensor chip 29. A protective member 28b is disposed in the space surrounded by the sleeve 27b so that the sensor chip 29 and the bonding wire 30 are sealed.

  The lid 50 is formed with a through hole 50 a that communicates the external space with the space in the recess 13. For this reason, the temperature of the space in the recess 13 becomes equal to the temperature of the external space, and the sensor chip 29 outputs a reference signal corresponding to the temperature of the external space.

  Then, the circuit chip 23 compares the detection signal output from the sensor chip 22 with the reference signal output from the sensor chip 29 to determine whether or not the insertion portion 16 is inserted in the tube 3. .

  That is, when the insertion portion 16 is inserted in the tube 3, the sensor chip 22 outputs a detection signal corresponding to the temperature of the space 3a of the tube 3, and the sensor chip 29 outputs a reference signal corresponding to the temperature of the external space. To do. On the other hand, when the insertion part 16 is not inserted in the tube 3, the sensor chip 22 outputs a detection signal corresponding to the temperature of the external space. For this reason, by comparing the detection signal output from the sensor chip 22 with the reference signal output from the sensor chip 29, it is determined whether or not the insertion portion 16 is inserted in the tube 3.

  Thus, even if it is determined whether the insertion portion 16 is inserted in the tube 3 by comparing the temperature of the space 3a of the tube 3 and the temperature of the space outside the tube 3, the first The same effect as the embodiment can be obtained.

(Other embodiments)
The present invention is not limited to the embodiment described above, and can be appropriately changed within the scope described in the claims.

  For example, in the first embodiment, the example in which the cooling pipe 7 for cooling the internal combustion engine is used as the temperature adjusting means has been described. However, the temperature adjusting means only needs to be able to cool the space 3 a of the tube 3. A cooling member for cooling the space 3a may be newly arranged. Moreover, you may use what heats the space 3a of the tube 3 as a temperature adjustment means. For example, you may make it heat the space 3a of the tube 3 by arrange | positioning the waste heat piping which flows waste heat in the recessed part 4a.

  Furthermore, in the said 1st Embodiment, when the space 3a of the tube 3 is cooled, since a pressure also changes with temperature, based on the sensor signal (detection signal) according to the pressure output from the sensor chip 22, You may make it determine whether the insertion part 16 is inserted in the tube 3. FIG. In this case, the sensing unit that outputs a sensor signal corresponding to the pressure corresponds to the pressure detection element and the detection means of the present invention. Similarly, in the second embodiment, the sensor chip 29 outputs a reference signal corresponding to the external pressure, and based on the sensor signal (detection signal) output from the sensor chips 22 and 29 and the reference signal, You may make it determine whether the insertion part 16 is inserted in the tube 3. FIG.

  In the first embodiment, the circuit chip 23 determines whether or not the port portion 12 is inserted into the tube 3 based on the detection signal. However, in the ECU 9, the port portion 12 is the tube. 3 may be determined. In this case, the ECU 9 corresponds to the determination means of the present invention.

3 Tube 9 ECU
DESCRIPTION OF SYMBOLS 10 Case 11 Main-body part 12 Port part 22 Sensor chip 23 Circuit chip

Claims (7)

A pressure detecting element (22) for outputting a sensor signal corresponding to the pressure;
A case having a main body portion (11) for mounting the pressure detection element, and a port portion (12) connected to the main body portion and having a pressure introduction hole (15) for introducing the pressure into the pressure detection element. (10)
One end portion of the port portion opposite to the main body portion is inserted into the opening portion of the mounted member (3) having a space (3a) therein and having an opening portion, and pressure in the space of the mounted member In the mounting structure of the pressure sensor that detects
Temperature adjusting means (7) for changing the temperature of the space of the mounted member;
Detection means (22) for outputting a detection signal corresponding to the state of the space of the mounted member;
Mounting of a pressure sensor, comprising: determination means (9, 23) for determining whether one end portion of the port portion is inserted into the attached member based on the detection signal Construction.   2. The pressure according to claim 1, wherein the determination unit determines whether one end portion of the port portion is inserted into the attached member by comparing the detection signal with a threshold value. 3. Sensor mounting structure. Detection means (29) for outputting a reference signal corresponding to the state of the external space in which the attached member is disposed;
The said determination means determines whether the one end part of the said port part is inserted in the said to-be-attached member by comparing the said detection signal and the said reference signal. Mounting structure of pressure sensor.   The pressure sensor mounting structure according to any one of claims 1 to 3, wherein the temperature adjusting means cools a space of the attached member.   The pressure sensor mounting structure according to any one of claims 1 to 3, wherein the temperature adjusting means heats a space of the attached member.   6. The pressure sensor according to claim 1, wherein the detection means for outputting the detection signal outputs the detection signal in accordance with a temperature of the space of the attached member. Implementation structure. The detection means for outputting the detection signal outputs the detection signal according to the pressure in the space of the attached member, and is the pressure detection element. A mounting structure of the pressure sensor according to one.

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