JP2001123921A - Heating resistance element type air flow rate measuring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To supply a reliable air flow rate measuring device by improving a reliability on the product life of the air flow rate measuring device for measuring the intake air amount of the internal combustion engine of an automobile. SOLUTION: A thin and long groove for inserting and adhering a sub-air passage is provided on one part of a housing. One part of a conductive member for supporting a heating resistance element and temperature sensitive resistance element is exposed in a plane shape in the groove and covered by an adhesive for adhering the housing with the sub-air passage.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air flow measuring device for measuring an intake air flow of an internal combustion engine, and more particularly to a heating resistor type air flow measuring device for measuring an air flow taken into an automobile engine.

[0002]

2. Description of the Related Art As a prior art heating resistor type air flow measuring device, there is a technology disclosed in Japanese Patent Application Laid-Open No. Hei 3-233168. In this technology, a housing portion containing an electronic circuit and a sub air passage portion are integrated. And the housing part and the auxiliary air passage are arranged in a plane.

[0003]

In the above-mentioned prior art, the conductive member for electrically connecting the heating resistor and the temperature-sensitive resistor to the electronic circuit is filled with a resin. Gases and liquids enter and exit from the minute gaps, and the reliability of the product life has not been sufficiently considered.

[0004]

In order to solve the above-mentioned problems, a heating resistor, a temperature-sensitive resistor, and an electric wire are provided in grooves for fitting and bonding a housing and a sub air passage, a housing and a cover, and a housing and a base. By exposing a part of the conductive member to be electrically connected and covering the periphery of the conductive member with an adhesive, the gas and liquid that enter and flow out of the smile gap between the conductive member and the resin are shut off, and the heat is generated. The reliability of the product life of the resistor type air flow device can be improved.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view (A-A cross-sectional view of FIG. 2) of an air flow measuring device showing one embodiment of the present invention, FIG. 2 is a cross-sectional view of the embodiment shown in FIG. FIG. 2 is an enlarged X view of the embodiment shown in FIG.

An air flow meter body 3 has a main air passage 1 and a sub air passage 2 having a heating resistor 4 for detecting an air flow and a temperature sensitive resistor 5 for detecting an intake air temperature. The heating resistor and the temperature-sensitive resistor are electrically connected to the electronic circuit 7 via the conductive support member 6,
The housing 8 that protects the electronic circuit inside is adhered and integrated with the sub air passage, and the housing and the electronic circuit whose inside is protected by the housing are arranged in the main air passage.

The conductive member is covered with a mold member which is an insulating member of a housing, and the housing has projections 9 of the insulating member provided in the auxiliary air passage.
Is provided with an elongated groove 10 for fitting / adhering a part of the conductive member.
Part of the conductive member exposed in the groove is covered with an adhesive.

According to the present structure, even if the airtightness of the interface between the conductive member of the housing, which is an insert mold component for inserting the conductive member, and the mold member, which is the insulating member, is not sufficiently satisfied, the conductive member can be formed. By covering the groove exposing the part of the insulating component from the insulating component with an adhesive, the airtightness of the conductive member and the mold member as the insulating member can be improved.

As a result, the outflow of silicone gel and the intrusion of gas and liquid can be prevented from the interface between the conductive member and the mold member which is an insulating member, and the reliability of the air flow measuring device can be further improved. .

Further, by adding the function of improving the airtightness of the mold member, which is a conductive member and an insulating member, to a groove provided for bonding the housing and the sub air passage, the product can be downsized. it can.

Further, when assembling the product, the conductive member exposed in the groove is exposed in a plane, so that the conductive member does not become an obstacle when applying the adhesive,
In addition, since the grooves are linear, the structure is such that the adhesive is easily applied, so that the assembly can be automated and the assemblability can be improved.

FIG. 4 shows an embodiment of the present invention, and FIG. 5 shows a portion corresponding to the X enlarged view of FIG.

In this structure, a groove 10 is provided so that the entire surface of the conductive member is exposed.

According to this structure, the same function and effect as those of the embodiment shown in FIGS. 1 to 3 can be expected.

Further, according to this structure, since the entire surface of the conductive component is exposed from the insulating component, the adhesive can cover the entire surface of the conductive member, and the molding member which is an insulating member can be used. Can be further improved in airtightness.

[0016] Thus, the outflow of silicone gel and the intrusion of gas and liquid can be further prevented from the interface between the conductive member and the mold member, which is an insulating member, and the reliability of the air flow measuring device can be further improved. did.

Further, when molding a housing which is an insert mold part for inserting a conductive member, it is also possible to hold an intermediate portion of the conductive member to be inserted, so that the moldability of the housing can be improved. did.

An embodiment of the present invention will be described with reference to the drawings. FIG. 5 is a cross-sectional view (a cross-sectional view taken along the line AA in FIG. 2) of the air flow measuring device showing one embodiment of the present invention, and FIG.
FIG. 6 is a Y enlarged view of the embodiment shown in FIG.

In this structure, the periphery of the conductive member is covered with a mold member which is an insulating member of the housing, and the projection 9 of the insulating member provided on the cover 11 is fitted and adhered to the housing. An elongated groove 10 is provided,
In the groove, a part of the conductive member is exposed in a planar shape, and a part of the conductive member exposed in the groove is covered with an adhesive.

In this structure, the same operation and effect as those of the embodiment shown in FIGS. 1 to 3 can be expected. As a result, the outflow of silicone gel and the intrusion of gas and liquid can be further prevented from the interface between the conductive member and the mold member, which is an insulating member, and the reliability of the air flow measuring device can be further improved.

In the embodiments described so far, the description has been made mainly of the groove for fitting and bonding the housing and the cover and the housing and the cover. However, the same function and effect can be obtained in the groove for fitting and bonding the housing and the base 28. Can be obtained.

Further, by using the structure described in the above embodiments also in the connector terminal 29 in the groove for fitting and bonding the housing and the cover, the same operation and effect can be obtained, and the inside of the housing for protecting the interior of the circuit can be obtained. Airtightness can be maintained.

FIG. 7 is a sectional view of a throttle body 13 having a valve 12 for controlling intake air of an engine, showing one embodiment of the present invention. In the throttle body, an air flow meter integrated with a sub air passage is disposed upstream of the valve. The air flow meter is shown in FIG.
This embodiment is the same as the embodiment shown in FIGS.

Although the present embodiment has been described with reference to the throttle body, a body having a valve 12 for controlling the intake air of the engine, for example, an ETC body has a structure in which a similar effect can be expected.

FIG. 8 is a part of a sectional view of an air cleaner disposed in an engine room, showing one embodiment of the present invention. The air cleaner has an upstream case member 14 having an intake duct for taking in the intake air flow rate, and a downstream case member 15 having a duct for introducing the intake air into the engine room.
This is a structure in which a filter member 16 for removing a duct in the air is sandwiched and fixed. In the air cleaner, an air flow meter with an integrated sub air passage is installed in a downstream case member. The air flow meter is the same as that of the embodiment shown in FIGS. 1 to 5, and has a structure capable of expecting the same operation and effect.

FIG. 9 shows an embodiment in which the present invention is applied to an electronic injection type internal combustion engine.

The intake air sucked from the air cleaner 17 passes through the body 3 of the heating resistor type air flow device, the intake duct 18, the throttle body 15, and the manifold 20 having the injector 19 to which fuel is supplied, to the engine cylinder 21. Inhaled.

On the other hand, the gas generated in the engine cylinder is
The gas is exhausted through the exhaust manifold 22. The air flow signal output from the electronic circuit of the heating resistor type air flow meter, the throttle valve angle signal output from the throttle angle sensor 23, the oxygen concentration signal output from the oximeter 24 installed in the intake manifold, and the engine The control unit 26 which inputs the rotation angle signal output from the rotation speed 25 calculates these signals and controls the optimal fuel injection amount and the idle air control valve 27.

[0029]

According to the present invention, a gas and a liquid flowing in and out of a smiling gap between a conductive member and a resin of an insert molded part in which a conductive member is inserted are cut off, and a product of a heating resistor type air flow device is provided. It is possible to improve the reliability related to the service life.

[Brief description of the drawings]

FIG. 1 is a sectional view taken along line AA of FIG. 2 (only the module structure).

FIG. 2 is a cross-sectional view of an air flow measuring device according to one embodiment of the present invention.

FIG. 3 is an enlarged view of X in FIG. 1;

FIG. 4 shows an X of an air flow measuring device according to an embodiment of the present invention.
Enlarged view.

FIG. 5 is a sectional view of an air flow measuring device according to an embodiment of the present invention.

FIG. 6 is an enlarged view of Y in FIG. 5;

FIG. 7 is a cross-sectional view of a throttle body-integrated air flow measuring device according to an embodiment of the present invention.

FIG. 8 is a cross-sectional view of an air cleaner with a built-in air flow measuring device according to an embodiment of the present invention.

FIG. 9 is a control system diagram of an internal combustion engine using the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Main air passage, 2 ... Sub air passage, 3 ... Air flow meter body, 4 ... Heating resistor, 5 ... Temperature sensitive resistor, 6 ... Conductive member support, 7 ... Electronic circuit, 8 ... Insulation Housing of member, 9: protrusion of insulating member, 10: elongated groove, 11: cover, 12: throttle valve, 13: throttle body, 14: upstream case of air cleaner, 15: downstream case of air cleaner, 16: filter, 17: air cleaner ,
18 ... intake duct, 19 ... injector, 20 ... manifold, 21 ... engine cylinder, 22 ... exhaust manifold, 23 ... throttle angle sensor, 24 ... oxygen concentration meter, 25 ... rotation angle meter, 26 ... control unit,
27 ... idle air control valve, 28 ... base, 29 ... connector terminal.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Shinya Igarashi 2477 Takaba, Hitachinaka-shi, Ibaraki F-term in Hitachi Car Engineering Co., Ltd. 2F035 AA02 EA03

Claims (9)

[Claims] 1. A heating element disposed in an intake air flow path and electrically connected to the heating element to output a signal corresponding to the flow rate of the intake air for measuring an intake air flow rate of the internal combustion engine. A heat-generating resistor having an electronic circuit, a frame-shaped or box-shaped housing for internally protecting the electronic circuit, and a support member communicating with the inside and outside of the housing and supporting the heat-generating element outside the housing. In the body air flow measuring device, a slit-shaped groove or hole is formed in a frame portion of the housing communicating with the support member, and the support member is exposed inside the groove or hole, and the support member is A heating resistor type air flow measuring device, characterized in that the exposed portion is covered with an adhesive. 2. An electronic device in which a terminal for electrically connecting an electronic circuit to an external device or the like is integrated with a frame-shaped or box-shaped resin housing for protecting the interior of the electronic circuit. A slit-shaped groove or hole is formed in the frame portion to which the terminal communicates, the terminal is exposed inside the groove or hole, and the exposed portion of the terminal is covered with an adhesive. And electronic equipment. 3. The cover according to claim 1, wherein a groove is provided on the entire periphery of the frame of the housing, and the support member or the terminal is exposed in the groove and covers the open surface of the housing. By bonding to the groove,
The heating resistor type air flow measuring device or the electronic device, wherein the support member or the terminal is covered with an adhesive for bonding the cover. 4. The groove according to claim 1, wherein the groove or the hole provided in the housing and having the support member or the terminal exposed inside is formed by a cover having one surface covering an open surface of the housing. A heating resistor type air flow measuring device or electronic device, wherein an end surface is closed by another member for fixing the housing via an adhesive for fixing the housing and the housing. 5. The auxiliary air passage according to claim 1, wherein a part of the intake air flows into the slit-shaped groove or hole provided in the housing and forms a sub-air passage in which the heating element is disposed. A heating resistor type air flow measuring device, wherein a passage member is used as an adhesive groove for joining to the housing, and an exposed portion of the support member is covered with an adhesive. 6. The device according to claim 5, wherein the housing and the sub air passage member are juxtaposed by bonding on a substantially planar base member, and the slit-shaped groove or hole provided in the housing is A heating resistor type air flow measuring device or an electronic device, wherein the device is closed with an adhesive by a base member and the auxiliary air passage member. 7. The housing according to claim 1, wherein, in addition to the support member and the terminal, a component provided in communication with the inside and outside of the housing similarly to the support member and the terminal is provided on a frame portion of the housing. A heating resistor type air flow measuring device or an electronic device, wherein the heating resistor type air flow measuring device or the electronic device is coated with an adhesive inside a slit-shaped groove or hole. 8. The intake system component according to claim 1, 3, 4, 5, 6, 7, or 7, such as a body having an air cleaner, a duct, and a throttle to which a heating resistor type air flow measuring device can be attached. 9. A control system for an internal combustion engine using the first, third, fourth, fifth, sixth, seventh and eighth aspects.