JP5440344B2 - Intake manifold - Google Patents

Description

  The present invention relates to an intake manifold that returns EGR gas or blow-by gas into a surge tank.

(Conventional technology)
As an intake manifold that returns EGR gas or blow-by gas to the inside of a surge tank, a technique shown in Patent Document 1 is known.
The technique of Patent Document 1 will be described with reference to FIG. In addition, the same code | symbol as the [form for inventing] mentioned later and [Example] shows the same function thing.
A surge tank 2 is provided at the lower portion of the intake manifold. One of the two members J1 and J2 constituting the surge tank 2 is connected to the inside of the surge tank 2 from the outside of the intake manifold. A gas introduction pipe 8 that guides EGR gas or blow-by gas is integrally formed.

The gas introduction pipe 8 extends to the central portion of the surge tank 2 so that EGR gas or blow-by gas returned to the engine is supplied to each cylinder without deviation.
That is, as shown in FIG. 4, the gas introduction pipe 8 is long and extends from the outside to the center of the surge tank 2.

On the other hand, since the gas introduction pipe 8 is integrally formed with the member J1 constituting the surge tank 2 as described above, at least the inner diameter of the gas introduction pipe 8 is tapered in order to remove the mold. Provided.
Here, since the gas introduction pipe 8 is provided long, a taper is provided over a long range, and as a result, the inner diameter dimension of the gas introduction pipe 8 is reduced.

Thus, the conventional gas introduction pipe 8 is “long” and “thin”.
For this reason, the moisture contained in the EGR gas or blow-by gas tends to stay inside the gas introduction pipe 8. Therefore, in cold districts such as winter season, there is a concern that water staying inside the gas introduction pipe 8 may freeze and the gas introduction pipe 8 may be blocked, and EGR gas or blow-by gas may not be returned to the engine.

As another problem, since the gas introduction pipe 8 is integrally formed with the member J1 forming the surge tank 2, the “direction in which the gas introduction pipe 8 extends” is limited to the “die-cutting direction of the molding die”. Therefore, the degree of freedom for providing the gas introduction pipe 8 is small.
For this reason, there is a possibility that the degree of freedom in adjusting the distribution of EGR gas or blow-by gas may be reduced due to restrictions on vehicle mounting.

As a specific example, unlike in FIG. 4, due to restrictions on vehicle mounting, in the “vertical direction (left-right direction in FIG. 4)” with respect to the “die cutting direction (up-down direction in FIG. 4)” of the member J1. Even if a long gas introduction pipe 8 ”is required, it is difficult to provide the“ gas introduction pipe 8 that extends long in the vertical direction ”with respect to the“ die cutting direction ”of the member J1 with the conventional technique.
As a result, the length of the gas introduction pipe 8 is shortened due to the restriction of die cutting, and the EGR gas or blow-by gas cannot be guided to the central portion of the surge tank 2.

JP 2006-207469 A

  The present invention has been made in view of the above-described problems, and its object is to prevent EGR gas or blow-by from entering the central portion of the surge tank without preventing clogging due to freezing of water and without being restricted by mold release. To provide an intake manifold capable of guiding gas.

[Means of Claim 1]
The intake manifold of the means of claim 1 guides EGR gas or blowby gas from the end of the intake manifold to the center of the surge tank by an independent small chamber formed by joining a plurality of members constituting the intake manifold. It is.
For this reason, the gas introduction pipe should just connect the exterior of an intake manifold, and the inside of an independent small room, and can provide a gas introduction pipe short.

(First effect)
Thus, since the gas introduction pipe can be provided short, it is difficult for water to stay inside the gas introduction pipe, and there is no problem that the gas introduction pipe is blocked by freezing of water.
In addition, since the independent small chamber is formed by joining a plurality of members constituting the intake manifold, the passage sectional area of the independent small chamber can be easily increased. For this reason, the malfunction which an independent small room is obstruct | occluded by freezing of water can be avoided.
That is, blockage due to freezing of water is avoided in both the gas introduction pipe and the independent small room provided to guide EGR gas or blow-by gas from the outside to the central portion of the surge tank. It is possible to prevent a problem that gas is not returned to the engine.

(Second effect)
Unlike the prior art, since the gas introduction pipe can be provided short, it is possible to form the gas introduction pipe without being restricted by the removal of the mold.
Further, since the independent small chamber is formed by joining a plurality of members constituting the intake manifold, the independent small chamber can be formed without being restricted by the punching of the mold.
As a result, the EGR gas or blowby gas can be guided to the center of the surge tank without being restricted by the mold release, and the degree of freedom in adjusting the distribution of the EGR gas or blowby gas can be increased.

Furthermore, the independent small chamber in the intake manifold of the means of claim 1 is to guide the water inside the independent small chamber to the discharge port by utilizing a die cutting taper formed for die cutting.
In this way, the water inside the independent small room is discharged from the discharge port using the die-cut taper, so that water does not collect inside the independent small room and the water freezes inside the independent small room. Can be surely prevented.

[Means of Claims 2 and 3 ]
The intake manifold of the means of claim 2 and claim 3 is provided with one or a plurality of sub-discharge ports in an independent small chamber separately from the discharge port, and the opening of the sub-discharge port is determined from the opening area of the discharge port. A small area is provided.
Thus, by providing a sub discharge port separately from the discharge port, EGR gas or blow-by gas can be discharged over a wide range of the surge tank, and the mixing of EGR gas or blow-by gas in the surge tank is improved. Can do.

[Means of claim 4]
The plurality of members constituting the intake manifold of the means of claim 4 are made of resin and are joined by vibration welding.

(Example 1) which is explanatory drawing of the intake manifold of the state isolate | separated in the junction part of the 1st member and the 2nd member. (Example 1) which is sectional drawing which follows the AA line of FIG. (Example 1) which is sectional drawing which follows the BB line of FIG. It is sectional drawing of a surge tank (conventional example).

[Description of Embodiments] [Mode for carrying out the invention] will be described with reference to the drawings.
The intake manifold 1 includes a surge tank 2 having an enlarged passage cross-sectional area of the intake passage, and a plurality of intake air branched from the surge tank 2 to distribute the intake air in the surge tank 2 to each cylinder of the engine. The branch 3 is provided, and is formed by joining (for example, vibration welding) a plurality of members 4 to 6 (for example, a plurality of resin members).
The intake manifold 1 includes a gas center introduction means 7 that guides EGR gas or blow-by gas from the outside of the intake manifold 1 to the center of the surge tank 2.

This gas center introducing means 7
(A) a gas introduction pipe 8 provided at an end portion of the intake manifold 1 to communicate the outside and the inside of the intake manifold 1 and guide EGR gas or blow-by gas from the outside to the inside of the intake manifold 1;
(B) An independent small pipe that is formed by a combination of a plurality of members 4 to 6 constituting the intake manifold 1 and guides the EGR gas or blow-by gas introduced into the intake manifold 1 by the gas introduction pipe 8 to the central portion of the surge tank 2 Room 9 and
(C) EGR gas or blow-by introduced into the inside of the independent small room 9 provided in the central part of the surge tank 2 in the independent small room 9 and communicating with the inside of the independent small room 9 and the inside of the surge tank 2. An outlet 10 for discharging gas into the surge tank 2;
Consists of
The independent small chamber 9 guides the water inside the independent small chamber 9 to the discharge port 10 by using a die cutting taper formed for die cutting.
In addition, the independent small chamber 9 is introduced into the independent small chamber 9 by communicating with the inside of the surge tank 2 and a portion different from the central portion of the surge tank 2 in the independent small chamber 9 apart from the discharge port 10. One or a plurality of sub discharge ports 11 for discharging the EGR gas or blow-by gas that has been discharged into the surge tank 2 are provided, and the opening area of the sub discharge ports 11 is smaller than the opening area of the discharge ports 10.

The intake manifold 1 according to the first embodiment will be described with reference to FIGS. In the following embodiments, the same reference numerals as those in the above-mentioned [Mode for Carrying Out the Invention] denote the same functional objects.
[Overview of engine intake / exhaust system]
Before describing the characteristic technology of the first embodiment, a schematic configuration of an intake / exhaust device for an engine will be described.
An engine is an internal combustion engine for driving a vehicle (gasoline engine, diesel engine, etc.) that generates rotational output by combustion of fuel, an intake passage that guides intake air into each cylinder, and exhaust gas generated in each cylinder to the atmosphere. And an exhaust passage for discharging inside.

The intake passage is constituted by internal passages of the intake pipe, the intake manifold 1 and the intake port.
The intake pipe is a passage member that forms an intake passage from the outside air intake to the intake manifold 1. The intake pipe is an air cleaner that removes dust and dirt contained in the intake air sucked into the engine, and is sucked into the cylinder. A throttle valve or the like is provided for adjusting the intake flow rate.
The intake manifold 1 is an intake pipe that distributes the intake air supplied from the intake pipe to each cylinder of the engine, and a specific structure thereof will be described later.
The intake port is formed for each cylinder in the cylinder head of the engine, and guides the intake air distributed by the intake manifold 1 into each cylinder.

The exhaust passage is constituted by internal passages of an exhaust port, an exhaust manifold, and an exhaust pipe.
Like the intake port, the exhaust port is formed for each cylinder in the cylinder head of the engine, and guides exhaust gas generated in the cylinder to the exhaust manifold.
The exhaust manifold is a collecting pipe for exhaust gas discharged from each exhaust port. The exhaust pipe is a passage member that discharges exhaust gas toward the atmosphere. The exhaust pipe has a catalyst for purifying exhaust gas or a DPF (diesel particulate filter) that collects particulates contained in the exhaust gas. An abbreviation for filter) is provided.

The engine intake / exhaust system is provided with a blow-by gas reduction device. The blow-by gas reduction device includes blow-by gas piping that returns blow-by gas generated in the engine (a mixed gas of unburned gas and exhaust gas that has entered the crankcase from the combustion chamber of the engine) to the intake passage.
Specifically, the blow-by gas piping has a blow-by gas suction side connected to the cam cover of the engine and an intake side connected to the intake manifold 1. The intake manifold 1 is connected to the end of the blow-by gas piping. A gas introduction pipe 8 is provided.
In addition, one end of the blow-by gas piping, or in the middle of the blow-by gas piping, functions as a one-way valve that allows blow-by gas to flow only from the cam cover side to the intake manifold 1 side, and a PCV (purge control (Abbreviation of valve) is provided.

[Feature Technology 1 of Example 1]
The intake manifold 1 of the first embodiment is provided with gas center introduction means 7 for returning blow-by gas into a surge tank 2 formed inside the intake manifold 1.
First, the configuration of the intake manifold 1 will be described.
1 to 3 are sectional views of an intake manifold 1 attached to a four-cylinder engine.
The intake manifold 1 is an intake pipe that distributes intake air supplied from an intake pipe to each cylinder of the engine, and includes a surge tank 2 and four intake branches 3.
The surge tank 2 is formed to prevent intake pulsation and intake interference that adversely affect the accuracy of the flow rate sensor, and has an enlarged passage cross-sectional area of the intake passage.
The four intake branches 3 branch from the surge tank 2 and distribute and supply intake air in the surge tank 2 to each cylinder of the engine. Specifically, the intake branches 3 are arranged along the cylinder rows of the engine, and in this embodiment, each intake branch 3 is provided in a substantially C-shaped manner in a similar manner.

The intake manifold 1 is provided by joining the first member 4, the second member 5, and the third member 6 (the first to third members 4 to 6 are examples of a plurality of members).
The first member 4 is a member fastened to the engine and forms half (one side) of the surge tank 2.
The second member 5 is a member joined to the first member 4 and forms a half (the other) of the surge tank 2 and also forms a half (one) of each intake branch 3 curved in a substantially C shape.
The third member 6 is a member joined to the second member 5 and forms a half (the other side) of each intake branch 3 curved in a substantially C shape.

The first to third members 4 to 6 are all made of a thermoplastic synthetic resin, and are, for example, injection-molded into a predetermined shape with a nylon resin blended with glass fibers.
A welding seal portion that is welded by a vibration welding technique is provided at a joint portion between the first member 4 and the second member 5 and a joint portion between the second member 5 and the third member 6.
And by welding each welding seal part by a vibration welding technique, the 1st-3rd members 4-6 are joined and the intake manifold 1 is formed.

The intake manifold 1 is integrally provided with a gas center introduction means 7 for introducing blow-by gas from the outside of the intake manifold 1 to the center of the surge tank 2.
This gas center introducing means 7
(A) a gas introduction pipe 8 that is provided at an end of the intake manifold 1 (left end in FIG. 1), communicates the outside and the inside of the intake manifold 1 and guides the blowby gas from the outside to the inside of the intake manifold 1;
(B) Blow-by formed by a combination of a plurality of members 4 to 6 (in this embodiment, the first member 4 and the second member 5) constituting the intake manifold 1 and led into the intake manifold 1 by the gas introduction pipe 8 An independent small chamber 9 for guiding gas to the central portion of the surge tank 2, and (c) provided in the central portion of the surge tank 2 in the independent small chamber 9 to communicate the interior of the independent small chamber 9 with the interior of the surge tank 2. A discharge port 10 for discharging the blow-by gas introduced into the independent small chamber 9 toward the central portion of the surge tank 2;
Consists of

Each said structure is demonstrated concretely.
The gas introduction pipe 8 is connected to the end of the blow-by gas pipe described above outside the intake manifold 1 and sends the blow-by gas guided through the blow-by gas pipe to the inside of the intake manifold 1 (specifically, an independent small size). To the inside of the room 9).
As shown in FIG. 3, the gas introduction pipe 8 is formed integrally with the second member 5. The gas introduction pipe 8 only needs to have a function of connecting the inside and outside of the intake manifold 1 and connecting a blow-by gas pipe, and can be provided with a short axial length (pipe length dimension). For this reason, the inner diameter of the gas introduction tube 8 can be formed by a core different from the molding die used when the second member 5 is molded.

The independent small chamber 9 is a chamber that forms a passage provided to guide the blow-by gas introduced into the intake manifold 1 by the gas introduction pipe 8 to the central portion of the surge tank 2. It is formed by joining the members 5.
Further, the passage sectional area for flowing blow-by gas in the independent small chamber 9 is provided several times or more than the passage sectional area of the gas introduction pipe 8 (in this embodiment, 10 times or more as shown in FIG. 2). .

  The discharge port 10 is an opening hole that communicates the inside of the surge tank 2 and the inside of the independent small room 9 at the center of the surge tank 2, and is formed in a partition wall that partitions the independent small room 9 and the surge tank 2. The By providing in this way, the blow-by gas guided toward the central portion of the surge tank 2 through the independent small chamber 9 is discharged toward the central portion of the surge tank 2. The opening area of the discharge port 10 (opening hole) is sufficiently larger than the passage cross-sectional area of the gas introduction pipe 8.

(Effect 1 of Example 1)
As described above, the intake manifold 1 of the first embodiment can be provided with the gas introduction pipe 8 short.
Further, even if the inner diameter of the gas introduction pipe 8 is tapered to remove the molding die, since the gas introduction pipe 8 is provided short, it is possible to prevent the inner diameter of the gas introduction pipe 8 from being reduced due to the taper. it can.
As described above, since the gas introduction pipe 8 is short and the inner diameter is prevented from being narrowed, it is difficult for water to stay inside the gas introduction pipe 8, and the inside of the gas introduction pipe 8 is blocked by freezing of water. Is avoided.

On the other hand, the independent small chamber 9 that guides the blow-by gas to the central portion of the surge tank 2 is formed by joining the first member 4 and the second member 5 as described above. The passage cross-sectional area can be easily set large. For this reason, the malfunction that the inside of the independent small room 9 is obstruct | occluded by freezing of water does not arise.
That is, in the intake manifold 1 of the first embodiment, blockage due to freezing of water is avoided in both the gas introduction pipe 8 and the independent small chamber 9 provided to guide blow-by gas from the outside to the central portion of the surge tank 2. Therefore, the trouble that blow-by gas is not returned to the engine due to water freezing can be prevented.

(Effect 2 of Example 1)
Since the intake manifold 1 of the first embodiment can be provided with the gas introduction pipe 8 short as described above, the inner diameter of the gas introduction pipe 8 can be formed by the core.
On the other hand, since the independent small chamber 9 is also formed by joining the first member 4 and the second member 5 constituting the intake manifold 1, the independent small chamber 9 is formed without being restricted by the punching of the mold. can do.
Thereby, blow-by gas can be led to the central part of the surge tank 2 without being restricted by the die-cutting of the mold, and the degree of freedom of blow-by gas distribution adjustment can be increased.

[Feature Technology 2 of Example 1]
As described above, the gas introduction pipe 8 is provided integrally with the second member 5.
The independent small chamber 9 is provided by joining the first member 4 and the second member 5 as described above.
For this reason, the water discharged from the gas introduction pipe 8 into the independent small chamber 9 is guided to the bottom surface α of the independent small chamber 9 (surface formed in the second member 5) by gravity. That is, the bottom surface α through which water is guided in the independent small chamber 9 is formed in the second member 5.

On the other hand, the bottom surface α through which water is guided in the independent small chamber 9 is tapered for die cutting when the second member 5 is molded.
Therefore, in the first embodiment, the water on the bottom surface α of the independent small chamber 9 is provided to the discharge port 10 by using a die cutting taper formed for die cutting.

Specifically, the intake manifold 1 is mounted on an engine (vehicle) with the upper side in FIG. 2 facing the sky and the lower side in FIG. The taper is used to guide the water on the bottom surface α of the independent small room 9 to the discharge port 10.
In this way, the water in the bottom surface α of the independent small room 9 is discharged from the discharge port 10 using the die-cut taper, so that the water does not stay on the bottom surface α of the independent small room 9, and the independent small room 9 It is possible to more reliably prevent water from freezing inside.

[Feature Technology 3 of Example 1]
In the independent small room 9 of the first embodiment, a sub discharge port 11 is provided in addition to the discharge port 10.
The sub discharge port 11 is a part different from the discharge port 10 and communicates the independent small chamber 9 and the inside of the surge tank 2. Specifically, the sub-exhaust port 11 of this embodiment is provided inside the independent small chamber 9 and the surge tank 2 in the middle of the gas flow direction in the independent small chamber 9 (intermediate portion between the gas introduction pipe 8 and the exhaust port 10). It communicates with. The opening area of the sub discharge port 11 (the area of the opening hole) is smaller than the opening area of the discharge port 10.

Thus, by providing the sub discharge port 11 separately from the discharge port 10, blow-by gas can be discharged over a wide range of the surge tank 2, and the mixability of blow-by gas in the surge tank 2 can be improved. .
In addition, in this Example 1, although the example which provides the sub discharge port 11 is shown, two or more may be provided and the mixability of gas may be improved.

  In the above embodiment, the blow-by gas is introduced into the surge tank 2 by the gas center introduction means 7. However, the EGR gas may be provided so as to be introduced into the surge tank 2 by the gas center introduction means 7.

DESCRIPTION OF SYMBOLS 1 Intake manifold 2 Surge tank 3 Intake branch 4 1st member (one of several members)
5 Second member (one of a plurality of members)
6 Third member (one of a plurality of members)
7 Gas center introduction means 8 Gas introduction pipe 9 Independent small chamber 10 Discharge port 11 Sub exhaust port α Bottom surface of independent small chamber (surface on which a die-cut taper is formed)

Claims (4)

A surge tank (2) having an enlarged passage cross-sectional area of the intake passage;
A plurality of intake branches (3) branched from the surge tank (2) to supply the intake air in the surge tank (2) to each cylinder of the engine;
In the intake manifold (1) formed by joining a plurality of members (4-6),
The intake manifold (1) includes gas center introduction means (7) for introducing EGR gas or blow-by gas from the outside of the intake manifold (1) to the center of the surge tank (2).
This gas center introduction means (7)
(A) Provided at the end of the intake manifold (1), communicates the outside and the inside of the intake manifold (1), and guides EGR gas or blow-by gas from the outside to the inside of the intake manifold (1). A gas introduction pipe (8);
(B) EGR gas or blow-by formed by a combination of the plurality of members (4 to 6) constituting the intake manifold (1) and guided into the intake manifold (1) by the gas introduction pipe (8). An independent chamber (9) for guiding gas to the center of the surge tank (2);
(C) The independent small chamber (9) is provided at a central portion of the surge tank (2), and communicates the inside of the independent small chamber (9) with the inside of the surge tank (2). A discharge port (10) for discharging the EGR gas or blow-by gas introduced into the room (9) into the surge tank (2);
Consists of
The independent small chamber (9) is configured to guide water inside the independent small chamber (9) to the discharge port (10) by using a die cutting taper formed for die cutting. Intake manifold to be used. A surge tank (2) having an enlarged passage cross-sectional area of the intake passage;
A plurality of intake branches (3) branched from the surge tank (2) to supply the intake air in the surge tank (2) to each cylinder of the engine;
In the intake manifold (1) formed by joining a plurality of members (4-6),
The intake manifold (1) includes gas center introduction means (7) for introducing EGR gas or blow-by gas from the outside of the intake manifold (1) to the center of the surge tank (2).
This gas center introduction means (7)
(A) Provided at the end of the intake manifold (1), communicates the outside and the inside of the intake manifold (1), and guides EGR gas or blow-by gas from the outside to the inside of the intake manifold (1). A gas introduction pipe (8);
(B) EGR gas or blow-by formed by a combination of the plurality of members (4 to 6) constituting the intake manifold (1) and guided into the intake manifold (1) by the gas introduction pipe (8). An independent chamber (9) for guiding gas to the center of the surge tank (2);
(C) The independent small chamber (9) is provided at a central portion of the surge tank (2), and communicates the inside of the independent small chamber (9) with the inside of the surge tank (2). A discharge port (10) for discharging the EGR gas or blow-by gas introduced into the room (9) into the surge tank (2);
Consists of
The independent small chamber (9) is different from the discharge port (10) in a portion different from the central portion of the surge tank (2) in the independent small chamber (9), and the inside of the surge tank (2). And one or a plurality of sub-discharge ports (11) for discharging the EGR gas or blow-by gas introduced into the independent small chamber (9) into the surge tank (2),
The intake manifold is characterized in that an opening area of the sub discharge port (11) is smaller than an opening area of the discharge port (10) . Intake manifold (1) according to claim 1 ,
The independent small chamber (9) is different from the discharge port (10) in a portion different from the central portion of the surge tank (2) in the independent small chamber (9), and the inside of the surge tank (2). And one or a plurality of sub-discharge ports (11) for discharging the EGR gas or blow-by gas introduced into the independent small chamber (9) into the surge tank (2),
The intake manifold is characterized in that an opening area of the sub discharge port (11) is smaller than an opening area of the discharge port (10). Intake manifold (1) according to any of claims 1 to 3,
The plurality of members (4 to 6) constituting the intake manifold (1) are made of resin and joined by vibration welding.

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