JP2002235616A - Intake device for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an intake device for an internal combustion engine capable of reducing cost by reducing the number of parts related to a pressure sensor in a filter, etc., and commonly using them. SOLUTION: In an intake manifold 20 of this intake device, a mounting part 26 dedicated for the pressure sensor for mounting the pressure sensor 50 to detect pressure of intake air is resin-molded integrally with the intake manifold 20. The mounting part includes a holding part 26a to fix the pressure sensor by a bolt, etc., an enclosure part 26b to enclose and seal a sensing port part 51 of the pressure sensor, and a passage part 26c of a labyrinth structure opened in the intake manifold to be communicated with the enclosure part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake device for an internal combustion engine in which an air cleaner, an intake manifold, and the like are integrated. The present invention relates to an improvement in a mounting structure of a pressure sensor.

[0002]

2. Description of the Related Art Internal combustion engines (engines) mounted on vehicles
Is composed of an air cleaner, a throttle, a surge tank, an intake manifold and the like. When the driver depresses the accelerator pedal, the throttle valve is opened in conjunction with the accelerator pedal, and the amount of intake air to the engine, that is, the amount of air-fuel mixture including fuel increases, thereby increasing the engine output. When the amount of intake air increases, the amount of fuel injection also needs to increase accordingly. However, usually, the flow rate of intake air is measured using an airflow sensor, and the engine control device ( The optimal fuel injection amount is determined by the ECU.

[0003] By the way, in places where the atmospheric pressure changes extremely, such as at high altitudes, it is necessary to detect the atmospheric pressure with a pressure sensor to correct the amount of intake air. Must be attached to the intake device. In this case, since the pressure sensor is used as atmospheric pressure detecting means, it is not desirable to set the pressure sensor at a portion to which another pressure is applied. Therefore, the outside air (for example, the atmosphere in the engine room) containing oil, water, dust and the like is directly sensed. However, most of recent pressure sensors are configured using a semiconductor element, and when a contaminant such as dust or oil is mixed and adhered to a semiconductor surface as a detection element, a problem such as a decrease in detection sensitivity occurs. A protection tube such as a vacuum hose, a filter, and the like are attached to the tip of the sensing port to prevent dust and water from entering.

[0004] An intake device disclosed in Japanese Patent Application Laid-Open No. H11-82198 is known as a device that adopts such measures. As shown in FIG. 4, the intake device includes a pedestal 82 as a first filter container formed by using a part of a housing of the surge tank 30 and a pressure sensor 100 from an internal space of the surge tank 30. Member 84 for removing contaminants such as dust and oil contained in the air guided to the filter 84
And the filter member 84 placed on the pedestal 82
A pressure sensor 100 is attached to a gas filter 80 including a cover 86 as a second filter container sandwiched together with the pressure sensor 100.
Is attached. However, this conventional air intake device requires a protection component such as a filter against intrusion of foreign matters such as water, oil, and dust from the outside air, which leads to an increase in the number of components and an increase in cost. there were.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above problems, and has as its object to reduce the number of parts around a pressure sensor such as a filter and to reduce the cost by sharing parts. It is to provide a possible intake device for an internal combustion engine.

[0006]

According to the present invention, there is provided an intake device for an internal combustion engine according to the present invention as means for solving the above-mentioned problems. In the intake device for an internal combustion engine according to the first aspect, a mounting portion dedicated to the pressure sensor for mounting the pressure sensor for detecting the pressure of the intake air is formed by resin molding integrally with the intake manifold. Therefore, the number of parts and the cost can be reduced.

According to a second aspect of the present invention, in the intake device, a mounting portion dedicated to the pressure sensor molded integrally with the intake manifold is formed of a holding portion for holding the pressure sensor and a part or the entire circumference of a sensing port portion of the pressure sensor. And a surrounding portion for surrounding, whereby it is possible to prevent intrusion of water and dust from the outside, and it is possible to maintain a good function of the pressure sensor. According to a third aspect of the present invention, there is provided the intake device, wherein the mounting portion dedicated to the pressure sensor molded integrally with the intake manifold is configured to surround the holding portion for holding the pressure sensor and a part or the entire periphery of the sensing port portion of the pressure sensor. And a passage that communicates with the surrounding portion and has a maze structure in which a passage that is opened inside the intake manifold has a maze structure.
Since the intrusion of water, dust and the like into the pressure sensor from the outside and the outside air can be prevented without providing a filter, the cost can be reduced by reducing the number of parts.

According to a fourth aspect of the present invention, the passage portion of the maze structure is such that the horizontal portion is slightly inclined so that foreign matter caught in the horizontal portion does not stay there. Can be prevented from being clogged by foreign substances, and the detection sensitivity of the pressure sensor can be prevented from lowering.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An intake system for an internal combustion engine (engine) according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view of an intake device for an engine to which the present invention is applied, and FIG. 2 is a sectional view taken along line II-II in FIG. The intake device includes an air cleaner unit 10 that removes dust contained in air taken in from the intake port 12, an intake manifold 20 having a fixed portion 22 for attaching the intake device to the engine 90 formed at one end, and an intake manifold 20. , A throttle 40 attached to the center of the surge tank 30, a pressure sensor 50 attached to the intake manifold 20, and a passage 60 connecting the throttle 40 and the air cleaner unit 10.
It is composed of

The air cleaner section 10 includes an air cleaner element 14 made of nonwoven fabric or filter paper, a guide 16 for mounting and storing the air cleaner element 14, and an air cleaner element 14.
And a clean side case 19 forming a clean side space downstream. The air introduced into the dusty side space through the inlet 12 is cleaned of dust by passing through the air cleaner element 14 and is introduced into the clean side space.

The passage 60 is a cylindrical member formed as a part of the cap 72, and
4 guides the air passed through the clean side space to the surge tank 30 through the throttle 40. The throttle 40 includes a throttle valve 42 and a throttle body 44.
The amount of air sucked into each of the 0 cylinder rows is adjusted.
Further, a position sensor 48 for detecting the opening of the throttle valve 42 is attached to the throttle 40, and the output of this sensor is transmitted to an engine control device (E) (not shown).
CU).

The surge tank 30 has a box shape, and a throttle 40 is attached to the center of one surface of the box shape.
Air flows into the interior. An intake manifold 20 is attached to the other surface of the box shape, and a surge tank 30 is provided.
The inside air is led out to the intake manifold 20.

The intake manifold 20 includes a surge tank 30.
This is for introducing the air from which the dust introduced via the refuse has been removed into each cylinder row of the engine 90, and is constituted by the same number of branch pipes 24 as the number of cylinders of the engine 90. A fixing portion 22 for attaching the intake device to the engine 90 is formed at the end of each branch pipe 24. By tightening a bolt or the like into a through hole 25 provided in the fixing portion 22, an intake air to the engine 90 is obtained. The device is mounted.

In this embodiment, a pressure sensor 50 for correcting the atmospheric pressure of the intake air amount is attached to the intake manifold 20. The pressure sensor 50 has a detection unit formed of, for example, a semiconductor element, detects the pressure in the intake manifold 20, and outputs the sensor output to the ECU to be used for correcting the flow rate of the intake air. .

FIG. 3 shows a detailed mounting structure of the pressure sensor 50 to the intake manifold 20. Pressure sensor 5
In order to hold the small-diameter cylindrical sensing port portion 51 and the pressure sensor 50 to the intake manifold 20,
Flanges 52 protruding from both side surfaces of the pressure sensor 50 are provided. On the other hand, a mounting portion 26 for mounting the pressure sensor 50 is formed on the intake manifold 20 by resin processing integrally with the intake manifold 20.

As shown in FIG. 3, the mounting portion 26 is provided with an intake manifold 2 for holding a pressure sensor 50.
0, a surrounding portion 26b projecting from a wall of the intake manifold 20 to surround a part or the entire periphery of the sensing port portion 51 of the pressure sensor 50, and a surrounding portion 26b. And a passage portion 26c communicating with the portion 26b and opening to the inside of the intake manifold 20, and forming a passage having a maze structure. In FIG. 3, the maze structure forms a passage that is bent about 90 °.

The holding portion 26a has an opening for fastening for a bolt or the like.
The pressure sensor 50 is held by the intake manifold 20 in such a manner that the two are fastened by aligning with the holes formed in 2 and tightening the bolts 53 and the like so that the sensing port portion 51 is inserted into the surrounding portion 26b. The pressure sensor 50 is attached to the intake manifold 20 such that a part or the entire circumference of the sensing port portion 51 of the pressure sensor 50 is inserted into the surrounding portion 26 b of the attachment portion 26. Sensing port unit 51
A gap is basically not formed between the surrounding portion 26b and the surrounding portion 26b. However, a sealing material may be appropriately provided so that water, dust, and the like do not enter the gap from the outside.

The passage portion 26c is formed continuously with the surrounding portion 26b, forms a continuous passage having a maze structure, and has a front end opening to the intake manifold 20. The shape of the maze structure may be any structure as long as it can be resin molded integrally with the intake manifold 20, but a very complicated structure is not preferred. As shown in FIG. 3, it is sufficient to have one bent portion. Further, when the maze structure has a passage in a horizontal portion, it is preferable that the passage in the horizontal portion has a certain degree of inclination because foreign matters are easily clogged.

As described above, in the intake device of the present invention, the pressure sensor 50 is integrated with the intake manifold 20.
Is formed. Therefore, the mounting portion 2
The number of components can be reduced as compared with the case where 6 is formed as a separate component. In addition, since a part or the entire circumference of the sensing port portion 51 of the pressure sensor 50 is surrounded, connection parts between the pressure sensor and the intake manifold are unnecessary, and
Intrusion of water, dust, etc. from the outside can be prevented. Furthermore, by having a passage portion having a maze structure, it is possible to prevent foreign matter such as water, oil, and dust from entering by outside air without using a filter, thereby reducing the number of components and simultaneously improving the function of the pressure sensor. Can be maintained.

[Brief description of the drawings]

FIG. 1 is a plan view of the overall structure of an intake device for an internal combustion engine according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a diagram showing a detailed mounting structure of the pressure sensor.

FIG. 4 is a diagram showing a conventional pressure sensor mounting structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Air cleaner part 20 ... Intake manifold 26 ... Mounting part 26a ... Holding part 26b ... Surrounding part 26c ... Passage part of a maze structure 30 ... Surge tank 40 ... Throttle 50 ... Pressure sensor 51 ... Sensing port part

Continued on the front page (72) Inventor Toshio Hayashi 1-1-1, Showa-cho, Kariya-shi, Aichi Prefecture Inside Denso Corporation (72) Inventor Takashi Chatani 1-1-1, Showa-cho, Kariya City, Aichi Prefecture Inside Denso Corporation

Claims (4)

[Claims] 1. An intake device for an internal combustion engine having a pressure sensor for detecting a pressure of intake air, wherein a mounting portion dedicated to the pressure sensor for mounting the pressure sensor is resin-molded integrally with the intake manifold. Engine intake device. 2. An intake device for an internal combustion engine having a pressure sensor for detecting a pressure of intake air, wherein a mounting portion dedicated to the pressure sensor for mounting the pressure sensor is resin-molded integrally with the intake manifold, and the mounting portion is An intake device for an internal combustion engine, comprising: a holding portion that holds the pressure sensor; and a surrounding portion that surrounds a part or the entire circumference of a sensing port portion of the pressure sensor. 3. An intake device for an internal combustion engine having a pressure sensor for detecting a pressure of intake air, wherein a mounting portion dedicated to the pressure sensor for mounting the pressure sensor is resin-molded integrally with the intake manifold, and the mounting portion is A holding portion that holds the pressure sensor, a surrounding portion that surrounds a part or the entire circumference of the sensing port portion of the pressure sensor, and a passage that communicates with the surrounding portion and that is opened inside the intake manifold has a maze structure. An intake device for an internal combustion engine, the intake device comprising: 4. The intake device for an internal combustion engine according to claim 3, wherein the passage portion of the maze structure slightly tilts the horizontal portion so that foreign matters caught in the horizontal portion do not stay there. .