JPH1182250A - Intake device for internal combustion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture the subject device with a mold of simple structure. SOLUTION: An intake manifold 20 and a housing 70 including an air cleaner case 18 have a straight tube shape mounting hole 28 connecting a mounting part 22 at a tip of the intake manifold 20 and the air cleaner case 18, and an injector 30 is attached to the mounting hole 28. As the mounting hole 28 is formed in a straight tube shape, a slide core required when forming the mounting hole 28 can be drawn to the mounting part 22 side when forming the housing 70 with a mold.

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.

[0002]

2. Description of the Related Art Conventionally, an internal combustion engine (engine) for a vehicle has been used.
A method of integrating the intake system components is known. For example, JP-A-8-210200 and JP-A-8-334
Japanese Patent Publication No. 070 discloses an "intake device for an internal combustion engine" in which an air cleaner, a throttle, a surge tank, an intake manifold and the like are integrally formed. By integrating the components of the intake device in this manner, the number of components and the number of assembly steps can be reduced, and space can be saved.

[0003]

In the intake device disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 8-210200, a mounting hole is formed in the vicinity of the tip of the intake manifold from the outer wall to the inner wall. Injector is installed. The mounting hole is formed in accordance with the shape of the distal end of the injector, and has a stepped shape whose diameter decreases from the outer wall to the inner wall of the intake manifold.

Therefore, considering the case where the intake manifold is formed by molding, it is necessary to set the direction in which the slide core used to form the mounting hole of the injector toward the outer wall of the intake manifold. Accordingly, a hydraulic mechanism and the like necessary for pulling out the slide core also need to be arranged on the outer wall side of the intake manifold.

However, the intake manifold has a curved shape, and depending on its shape and length, the space for disposing the hydraulic mechanism and the like required for pulling out the slide core used to form the mounting hole for the injector is reduced. There was a problem that the structure could not be sufficiently secured, and the structure of the mold became complicated. In particular, in the intake device disclosed in Japanese Patent Application Laid-Open No. 8-334070, a housing including a part of an intake manifold including a mounting hole of an injector and a dusty side case of an air cleaner portion is integrally formed. When the mounting hole of the above-described injector is to be formed therein, a hydraulic mechanism for extracting a slide core necessary for forming the mounting hole is disposed in the dusty side case, so that the structure of the molding die is particularly complicated. There was a problem of becoming.

The present invention has been made in view of the above points, and an object of the present invention is to provide an intake device for an internal combustion engine which can be manufactured using a mold having a simple structure.

[0007]

In order to solve the above-mentioned problems, in an intake device for an internal combustion engine according to the present invention, a shape of a mounting hole of a fuel injection device formed at an end of an intake manifold is changed by a step. It has a simple straight pipe shape, and the direction of pulling out the slide core necessary for molding the intake manifold including the mounting hole by a mold can be set on the side of the mounting portion to the internal combustion engine. Therefore,
By arranging the slide core and the hydraulic mechanism for extracting the slide core on the mounting portion side of the intake manifold, which has no structure that interferes with other parts, the structure of the entire mold including these slide cores and the hydraulic mechanism is not complicated, and a simple Structure types can be used.

In particular, when the above-mentioned intake manifold and the intake passage forming member are integrally formed, if the slide core is to be pulled out on the outer wall side of the intake manifold,
There is a possibility that the intake passage forming member and the direction in which the slide core is removed may interfere with each other. However, such a disadvantage does not occur when the slide core is removed from the mounting portion to the internal combustion engine. Also, when pulling out the slide core on the outer wall side of the intake manifold,
Since the mechanism for pulling out the slide core is arranged in the narrow intake passage, the structure of the molding die becomes complicated.However, when the slide core is pulled out on the side of the mounting part to the internal combustion engine, the mechanism for pulling out the slide core Can be arranged at a position separated from the intake passage, so that the structure of the molding die can be simplified.

In the case where an air cleaner case is considered as the above-described intake passage forming member, if a mechanism for pulling out the slide core is arranged in an air cleaner case having a box shape, the structure of the molding die becomes complicated. Instead, the shape of the air cleaner case itself must be matched to the molding die in order to accommodate the above-mentioned mechanism for pulling out the slide core in the air cleaner case, so that the degree of freedom in design is reduced, but the direction in which the slide core is pulled out In the case where is the mounting portion side of the internal combustion engine, there is no such restriction, there is a degree of freedom in product design or die design, and the air cleaner case can be downsized.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An intake system for an engine according to an embodiment of the present invention is characterized in that a shape of a mounting hole of an injector formed in an intake manifold is a straight tube having no steps. Hereinafter, an intake device for an engine according to an embodiment of the present invention will be specifically described with reference to the drawings.

FIG. 1 is a view showing the structure of an intake device for an engine according to an embodiment to which the present invention is applied. FIG. 2 is an enlarged sectional view taken along the line II-II shown in FIG. As shown in FIGS. 1 and 2, the air intake device of the present embodiment includes an air cleaner unit 10 that removes dust contained in air taken in from an intake port 12 and attaches the air intake device to an engine (not shown). An intake manifold 20 having an attachment portion 22 formed at one end, and each branch pipe 2 of the intake manifold 20
4, a delivery pipe 32 that supplies fuel to the injector 30, a surge tank 40 provided at the other end of the intake manifold 20, and an end of the surge tank 40. The throttle 50 includes a throttle 50 attached to the portion, and a passage 60 connecting the throttle 50 and the air cleaner portion 10.

The components of the above-described intake device are integrated. For example, as shown in FIG. 2, a part of the air cleaner section 10 and the intake manifold 2 are formed by the housing 70.
0 and a surge tank 40 are formed, and a cap 72 or the like including a part of the air cleaner unit 10 is attached thereto, and the whole is integrated. Hereinafter, the configuration of each part of the above-described intake device will be described in detail. The air cleaner unit 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,
The air cleaner case 18 includes a part of the housing 70 and the cap 72.
The air cleaner case 1 as an intake passage forming member
8, the upstream side of the intake air with respect to the air cleaner element 14 is called a dusty side case 80 and the downstream side is called a clean side case 82.
The space surrounded by 0 and 82 is called a dusty side space and a clean side space. In addition, a part of the intake passage is formed by the dusty side space and the clean side space.

The dusty side space in the dusty side case 80 and the clean side space in the clean side case 82 are separated by the air cleaner element 14 mounted on the guide 16 therebetween. The air introduced into the space passes through the air cleaner element 14 to remove dust and is introduced into the clean side space. This guide 16
Can be attached and detached by sliding in the vertical direction with respect to the flow of air through the air cleaner element 14, and when attached to the air cleaner unit 10, a seal member (not shown) formed on the outer periphery thereof allows The dusty side space and the clean side space are separated. Also, the guide 16 has a function as a cover that covers the mounting opening formed in the air cleaner case 18 without any gap, and prevents the air from flowing into the dusty side space through this opening. ing.

The passage 60 is provided in the air cleaner element 14.
For guiding the air passed through the clean side space to the surge tank 40 through the throttle 50, and is formed in a U-shape having a circular cross section. The throttle 50 includes a throttle valve and a throttle body, and adjusts an amount of air taken into each cylinder row of the engine. The throttle 50 has a pressure sensor 52 for detecting the pressure in the throttle 50.
And a position sensor 54 for detecting the opening of the throttle valve are attached, and the outputs of these sensors are input to an engine control unit (ECU) (not shown).

The surge tank 40 is for absorbing intake pulsation, and is provided with a throttle 5 attached to an end thereof.
The intake air is distributed to the respective branch pipes 24 of the intake manifold 20 via the intake manifold 20. Further, a trapper chamber 42 is formed by separating a part of the surge tank 40, and moisture and the like contained in blow-by gas leaking from each cylinder of the engine are removed.

The intake manifold 20 includes a surge tank 4
This is for introducing the air from which the dust introduced through the cylinder 0 has been removed into each cylinder row of the engine, and is constituted by the same number of branch pipes 24 as the number of cylinders of the engine. For example, the engine to which the intake device of the present embodiment is attached is a three-cylinder engine, and the intake manifold 20 has three branch pipes 2.
4. At the tip of each branch pipe 24 (the end opposite to the surge tank 40), a mounting portion 22 for mounting the intake device to the engine is formed, and a bolt insertion hole 26 provided in the mounting portion 22 is formed. The installation of the intake device to the engine is performed by tightening through a bolt (not shown).

The injector 30 injects fuel (gasoline) supplied from a tubular delivery pipe 32 as a fuel supply device into the engine at a predetermined timing. In the vicinity of the distal end of each branch pipe 24 of the intake manifold 20, there is formed a mounting hole 28 which penetrates a straight pipe by connecting the mounting surface of the mounting portion 22 and the dusty side space of the air cleaner portion 10. The injector 30 is inserted. The injector 30 is fixed by fixing the delivery pipe 32 attached to the end (the dusty side case 80 side of the air cleaner unit 10).

The intake device of this embodiment has such a structure, and its operation will be described next. The air taken into the dusty side case 80 of the air cleaner unit 10 from the inlet 12 passes through the air cleaner element 14 accommodated in the guide 16 to remove dust and is guided into the clean side case 82. Further, this intake air flows into the surge tank 40 via the throttle 50 after passing through the passage 60. Surge tank 40
Distributes the inflow air to the three branch pipes 24 of the intake manifold 20, and the distributed air is supplied to the respective cylinders of the engine via the respective branch pipes 24 together with the fuel injected from the injector 30. . The amount of air taken into each cylinder of the engine is controlled by the opening of a throttle valve in the throttle 50.

FIG. 3 is an enlarged sectional view showing details of the vicinity of the mounting hole 28 into which the injector 30 is inserted. As shown in the figure, the injector 30 has a multi-stage cylindrical shape whose outer diameter gradually decreases toward the engine side,
The front portion (tip portion) having the smallest outer diameter is delivered to the needle valve housing portion 310, the middle portion having the largest outer diameter is delivered to the solenoid coil housing portion 312, and the rear portion having the outer diameter slightly smaller than the middle portion is delivered. It is a pipe attachment part 314.

An opening for injecting fuel into the engine is formed in the tip end face of the needle valve housing 310, and mist gasoline injected through a needle valve (not shown) is mixed with the intake air. A disk-shaped injector mounting surface 316 is formed substantially at the center of the side surface of the solenoid coil housing portion 312, and a concave portion 318 that is one of the injector mounting surfaces 316 and circulates toward the distal end of the injector 30. Are formed. When the injector 30 is mounted in the mounting hole 28 formed in the housing 70, the concave portion 318 has an elasticity such as rubber to secure airtightness between the end surface 26 of the mounting hole 28 and the injector mounting surface 316. An O-ring 320 formed of a member is fitted.

A single concave portion 322 is formed on the outer peripheral side surface of the delivery pipe attaching portion 314.
By the O-ring 324 attached to the concave portion 322, the airtightness in the delivery pipe 32 attached behind the injector 30 is maintained. When fuel is supplied from the delivery pipe 32 to the injector 30, the injector 30 is pressurized by the fuel,
The injector mounting surface 316 formed on the side surface of the solenoid coil housing portion 312 is pressed against the end surface 26 of the mounting hole 28 formed on the housing 70, and the O-ring 320 sandwiched between these pressing surfaces is deformed and airtight. Is kept.

As described above, the mounting hole 2 for the injector 30 formed in the housing 70 of the intake device of the present embodiment.
Reference numeral 8 is a straight tube having a single diameter and no step so as to connect the air cleaner case 18 integrally formed with the intake manifold 20 and the mounting portion 22. Therefore, when the housing 70 is manufactured by molding, the pull-out direction of the slide core required for forming the mounting hole 28 described above can be set to the engine side (not shown).

Generally, when molding is performed using a slide core, it is necessary to provide a hydraulic mechanism for pulling out the slide core.
It is not easy to dispose them inside, and it is necessary to devise the shape of the housing 70 and the direction of the mounting hole 28. However, the slide core is attached to the mounting portion 22 of the intake manifold 20.
In the case of pulling out to the side, since the entire hydraulic mechanism and the like necessary for pulling out can be arranged outside the intake device, there is no member that interferes with the pulled-out slide core, the hydraulic mechanism, etc., and the housing 70 and the mounting hole The degree of freedom of the design of 28 is increased. In addition, since the slide core and the hydraulic mechanism for extracting the slide core need not be disposed in the narrow space in the air cleaner case 18, the molding die is not complicated and has a simple structure, so that the cost of the die can be reduced and the die can be reduced. Longer lifespan.

The injector 30 has one end face of the injector mounting surface 316 and the end face 2 on the housing 70 side.
6 and pressurize the O-ring 320 using the fuel pressure to maintain good airtightness between the inside of the intake manifold 20 and the inside of the air cleaner case 18. . In addition, the injector 30 shown in FIG.
2, an injector mounting surface 316 is formed substantially at the center,
This one surface is connected to the housing 70 via an O-ring 320.
Therefore, the distal end side is longer from the injector mounting surface 316, and the needle valve housing 310 can be protruded toward the engine side and approach the intake valve. The fuel injection position is preferably as close to the intake port of the engine as possible,
If the needle valve housing 310 can be protruded toward the engine side, the amount of fuel attached to the intake port is reduced, and ideal fuel injection becomes possible.

FIG. 4 is a partial sectional view showing a modified example of the intake device of the present embodiment, and shows a modified example of the mounting structure of the injector. Injector 130 shown in FIG.
Has a multi-stage cylindrical shape whose outer diameter gradually decreases toward the engine side, and has a needle valve housing 310, a solenoid coil housing 326, and a delivery pipe attachment 314 in order from the tip. The injector 130 differs from the injector 30 shown in FIG. 3 in the shape of the middle solenoid coil storage section 326. A disk-shaped injector mounting surface 328 is formed substantially at the center of the side surface of the solenoid coil housing portion 326, and a groove 332 for mounting the O-ring 330 on the needle valve housing portion 310 side from the injector mounting surface 328. Is formed.

From the delivery pipe 32 to the injector 13
When the fuel is supplied to the injector 0, the injector 130 is pressurized by the fuel toward the engine side.
28, the injector mounting surface 3
28 contacts the end face 26 of the mounting hole 28 of the housing 70, and the injector 130 is fixed. Further, an O-ring 330 is attached to a groove 332 formed on the outer periphery of the solenoid coil storage section 326.
The airtightness is maintained by pressing the inner wall 30 against the inner wall surface of the mounting hole 28 and deforming the same.

As described above, the side surface of the solenoid coil housing portion 326 of the injector 130 is
Mounting surface 32 for positioning and fixing the
8, the injector 130 may be attached to the straight tubular attachment hole 28 by providing a groove 332 for attaching an O-ring 330 for maintaining airtightness.

The present invention is not limited to the above embodiment, and various modifications can be made within the scope of the present invention. For example, in each of the embodiments described above, the intake manifold 20 having three branch pipes 24 has been described as an example. However, the number of branch pipes 24 can be appropriately changed according to the number of cylinders of the engine. In the above-described embodiment, the intake manifold 20 and the air cleaner case 18 are used.
Are described as being integrally formed, but the intake manifold 20 may be formed alone. Generally, since the intake manifold has a curved shape, a slide core is formed on the outer wall side of the intake manifold when an injector mounting hole is formed so as to connect an outer wall of the intake manifold to a mounting portion to the engine or an inner wall. Attempting to pull out the slide core may cause a part of the curved intake manifold to interfere with a hydraulic mechanism or the like necessary to pull out the slide core. For this reason, it is necessary to devise the structure of the molding die so as not to interfere, and to deform the shape of the intake manifold itself.However, the mounting hole of the injector is formed in a straight tubular shape, and the slide core is attached to the mounting portion side of the intake manifold. There is no such inconvenience when pulling out the. Therefore, when forming the intake manifold by itself,
The present invention can also be applied to a case where the intake manifold is formed integrally with an intake passage forming member (for example, a surge tank or the like) other than the air cleaner case.

[Brief description of the drawings]

FIG. 1 is a diagram showing a structure of an intake device for an engine according to an embodiment to which the present invention is applied.

FIG. 2 is an enlarged sectional view taken along line II-II shown in FIG.

FIG. 3 is a partially enlarged cross-sectional view showing an injector mounting structure.

FIG. 4 is a partially enlarged cross-sectional view showing a modification of the mounting structure of the injector.

[Explanation of symbols]

 Reference Signs List 10 air cleaner part 18 air cleaner case 20 intake manifold 28 mounting hole 30 injector 32 delivery pipe 40 surge tank 50 throttle 60 passage 70 housing 80 dusty side case 82 clean side case

Claims (3)

[Claims] 1. A straight pipe having a mounting hole for a fuel injection device formed at an end of an intake manifold on an internal combustion engine side, the mounting hole penetrating between an outer wall surface of the intake manifold and a mounting portion to the internal combustion engine. An intake device for an internal combustion engine. 2. The intake device for an internal combustion engine according to claim 1, wherein an intake passage forming member is formed integrally with the intake manifold. 3. The intake device for an internal combustion engine according to claim 2, wherein the intake passage forming member is an air cleaner case.