JP2002130063A - Seal structure of rotary valve in variable intake system of multi-cylinder internal combustion engine - Google Patents

Abstract

(57) Abstract: A variable intake device for a multi-cylinder internal combustion engine in which a plurality of intake passages are opened on the inner surface at the middle thereof and a rotary valve is rotatably inserted into an insertion hole provided in an intake manifold. The rotary valve is mounted on the intake manifold by improving the assemblability while ensuring a reliable seal. An inner surface of an insertion hole (20) is provided with an engagement groove (35) extending along the axis of the insertion hole (20). An arc-shaped seal ring 36 surrounding the seal ring 36 is mounted on each of a plurality of mounting grooves 46 provided on the outer periphery of the rotary valve 26, and the seal ring 36 and the rotary valve are provided at a plurality of locations spaced apart in the circumferential direction of the seal ring 36. A plurality of seal plates 37 extending in the axial direction of the insertion hole 20 so as to come into contact with the outer periphery of the insertion hole 26 are each provided with a fitting projection 41 that fits into a mounting groove 40 provided on the inner surface of the insertion hole 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a plurality of intake passages arranged in parallel, an insertion hole for opening an intermediate portion of each intake passage to an inner surface is provided in an intake manifold, and a rotary valve is rotated by the insertion hole. The present invention relates to an improvement in a seal structure of a rotary valve in a variable intake device of a multi-cylinder internal combustion engine that can be inserted.

[0002]

2. Description of the Related Art Conventionally, a variable intake device of a multi-cylinder internal combustion engine in which the length of an intake passage is changed by a rotary valve in accordance with the operation state of the internal combustion engine is disclosed in, for example, Japanese Patent Application Laid-Open No. H10-163,087.
000-8865 and JP-A-2000-8866
It is already known in Japanese Patent Publication No. Thus, Japanese Patent Application Laid-Open
In the variable intake device disclosed in Japanese Patent Publication No. 8865, a plurality of seal members slidably contacting the inner surface of an insertion hole provided in the intake manifold are fitted into annular grooves provided on the outer periphery of the rotary valve, respectively. The relative positions of the rotary valve and the seal member in the circumferential direction are fixed by engaging the lock portion provided at one position in the direction with the notch provided in the seal member. In addition, as described in
In the variable intake device disclosed in JP-A-00-8866,
An annular groove formed in the inner surface of the insertion hole at a plurality of locations spaced apart in the axial direction, so that the seal member cannot move along the axial direction and the circumferential direction of the insertion hole. Are fitted, and a lip provided in the seal member is inserted into an annular groove provided on the outer periphery of the rotary valve corresponding to the seal member so as to slide on one of the side walls of the annular groove. .

[0003]

However, in the above-mentioned prior art, since a plurality of seal members are individually attached to the rotary valve or the intake manifold, it is hard to say that the assembly is excellent in assemblability, and the insertion is difficult. When inserting the rotary valve into the hole, there is a concern that the attached seal member may fall off.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an improved multi-cylinder internal combustion engine in which a rotary valve can be mounted on an intake manifold by improving assemblability while ensuring reliable sealing performance. An object of the present invention is to provide a seal structure of a rotary valve in a variable intake device.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the invention according to claim 1 comprises a plurality of intake passages which are arranged in parallel corresponding to respective cylinders of a multi-cylinder internal combustion engine, and a plurality of the intake passages. An intake manifold having an axis extending in the direction in which the intake passages are arranged and an insertion hole for opening an intermediate portion of each of the intake passages on the inner surface is provided in the intake manifold, and one end of each of the intake passages is commonly connected to a single intake collecting chamber. A rotary valve rotatably inserted into the insertion hole can be switched between a state and a state where the middle of each of the intake passages is commonly communicated with the intake collecting chamber in accordance with the rotation of the insertion hole around the axis. In the variable intake device for a cylinder internal combustion engine, an engagement groove extending along an axis of the insertion hole is provided in an inner surface of the insertion hole, and an opening end of each of the intake passages to the inner surface of the insertion hole is connected to each other. Between A mounting groove is provided on the outer periphery of the rotary valve at a position corresponding to each of a plurality of partition walls provided on the intake manifold, and a rotary valve having a pair of arms at both ends for engaging with the engagement groove. Arc-shaped seal rings surrounding the seal ring and the outer periphery of the rotary valve at a plurality of locations spaced apart in the circumferential direction of each seal ring in the axial direction of the insertion hole. A plurality of extending seal plates are provided with fitting projections which extend in the axial direction of the insertion hole at positions corresponding to the seal plates and which fit into mounting grooves provided on the inner surface of the insertion hole. Features.

[0006] According to such a configuration, the plurality of seal rings mounted on the outer periphery of the rotary valve are pressed by the plurality of seal plates in contact with the plurality of locations on the outer periphery, so that the seal ring is attached to the rotary valve. The rotary valve, multiple seal rings, and multiple seal plates can be inserted into the insertion holes for assembly while securely holding the mounted state with each seal plate, making assembly of the rotary valve to the intake manifold easier. Can be improved. In addition, since the arms at both ends of each seal ring engage with the engagement groove on the inner surface of the insertion hole, the circumferential position in the insertion hole of each seal ring can be easily fixed, and the rotary valve of the rotary valve can be fixed. The position of each seal ring along the axial direction can be reliably determined by mounting the seal ring in each mounting groove. In addition, since the fitting projection of each seal plate is fitted into the mounting groove on the inner surface of the insertion hole, the position of each seal plate in the circumferential direction of the rotary valve is fixed. Is fixed and held on the intake manifold side, so that the inner circumference of each seal ring seals the rotary valve in the axial direction and each seal plate seals the rotary valve in the circumferential direction. In addition, it is possible to maintain a high intake charging efficiency in each cylinder of the multi-cylinder internal combustion engine. Moreover, since the outer periphery of each seal ring is in contact with the inner periphery of the seal plate fixedly held on the intake manifold together with the seal ring, each labyrinth passage formed between the inner periphery of the seal ring and the mounting groove has By suppressing the intake air leakage between the intake passages, it is possible to obtain a seal structure that minimizes the sliding resistance associated with the rotation of the rotary valve, and reduces the drive torque of the rotary valve. The weight of the variable intake device can be reduced.

[0007] The invention according to claim 2 provides the above-described claim 1.
In addition to the configuration of the invention described in the above, each of the seal plates is provided with a bead that comes into contact with the outer periphery of the rotary valve, and the outer periphery of each of the seal rings has a recess for fitting the bead of each seal plate. According to this configuration, each seal ring and each seal plate are mounted on the rotary valve so that the relative position of each seal ring and each seal plate along the circumferential direction of the rotary valve is easily determined. In addition to improving the assembly workability, the bead of each seal plate is brought into close contact with the outer periphery of the rotary valve, and the intake air leakage in the circumferential direction of the rotary valve is reliably suppressed, and the intake filling efficiency is improved. Can be further improved.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described based on one embodiment of the present invention shown in the attached drawings.

FIG. 1 to FIG. 10 show an embodiment of the present invention. FIG. 1 is a perspective view showing a rotary valve in a state where the engine is in a low rotational speed range through an intake manifold. 2 is a cross-sectional view of the variable intake device taken along a line 2-2 in FIG. 1, FIG. 3 is an enlarged view of a main part of FIG. 2, and FIG.
3 is a cross-sectional view corresponding to FIG. 3 at a portion along line -4, FIG. 5 is a perspective view corresponding to FIG. 1 in a state where the engine is in a middle rotation speed range, and FIG. FIG. 7 is a perspective view corresponding to FIG. 1 in a state where the engine is in a high rotational speed range, and FIG. 8 is a perspective view corresponding to FIG. 1 in a state where the engine is in a high rotational speed range. 9 is an exploded perspective view of the rotary valve, the seal ring and the seal plate, and FIG. 10 is an enlarged sectional view taken along line 10-10 of FIG.

Referring first to FIGS. 1 and 2, an intake manifold 15 of an in-line four-cylinder internal combustion engine has first, second, third and fourth intake passages 16A, 16B of substantially equal length individually corresponding to each cylinder. , 16C, 16D are provided in parallel in the cylinder arrangement direction, and one ends of the intake passages 16A to 16D are commonly connected to a single intake collecting chamber 17.

By the way, in the engine body to which the intake manifold 15 is connected, the first body corresponding to the first intake passage 16A is provided.
Cylinder, third cylinder corresponding to third intake passage 16C, fourth cylinder corresponding to fourth intake passage 16D, second intake passage 16B
Are ignited in the order of the second cylinders. Therefore, the first and fourth intake passages 16A and 16D arranged on both sides of the first to fourth intake passages 16A to 16D arranged in parallel.
In the first and fourth cylinders corresponding to the first and fourth cylinders, the intake strokes are not continuous with each other, and the second and third intake passages 16B, 1 adjacent to each other at the center of the first to fourth intake passages 16A to 16D.
In the second and third cylinders corresponding to 6C, the intake strokes are not continuous with each other.

As shown in FIG. 2, the first to fourth intake passages 16A to 16D are formed in the intake manifold 15 so as to be curved in a substantially C shape.
The intake air collection chambers 17 commonly connected to one ends of the air intake chambers A to 16D are held by curved intake air passages 16A to 16D together with the intake air inlet passages 18 arranged adjacent to the air intake collection chambers 17 so as to communicate with the air intake air collection chambers 17. It is provided in the intake manifold 15 so as to be held. The intake air is led to the intake passage 18 through an air cleaner and a throttle body (not shown). A communication hole 19 that communicates the intake passage 18 with the intake collecting chamber 17 is connected to the communication hole 19 and the intake hole 19. Each intake passage 1 through the collecting chamber 17
6A to 16D, the central portion of each of the intake collecting chambers 17 along the direction in which the intake passages 16A to 16D are arranged so that the length of each of the intake passages to one end of each of the intake collecting chambers 17 is substantially equal. It is arranged so as to communicate with the passage 18.

Referring to FIGS. 3 and 4, the intake manifold 15 includes first to fourth intake passages 16A to 16A.
D is provided with an insertion hole 20 having an axis extending in the arrangement direction of the intake passages 16A to 16D.
Is opened halfway. Thus, each of the intake passages 16A to 16D
Are formed in a substantially rectangular shape when viewed from the inside of the insertion hole 20, and a plurality of the opening ends 21 that sandwich the opening ends 21 between each other (in this embodiment, 5)
Are provided in the intake manifold 15 at equal intervals in the axial direction of the insertion hole 20.

At a portion corresponding to approximately one third of the entire circumference of the inner surface of the insertion hole 20, the insertion hole 2 is formed in the intake manifold 15.
The main body wall portion 23 is provided so as to separate the air inlet passage 18 from the air inlet passage 18. On the other hand, each of the intake passages 16A to 16D
Of the intake chamber 17 and the intake passages 16A-1
The side wall portions 24 interposed between the 6D are integrally provided with arcuate wall portions 25 slightly extending toward the intake air collecting chamber 17 so as to form a part of the insertion hole 20. 21 are defined at both ends along the circumferential direction of the insertion hole 20 by the main body wall portion 23 and the arc wall portions 25.
0 is formed so as to correspond to approximately 1/3 of the entire circumference of the inner surface. The upper part of the intake collecting chamber 17 is opened to the inner surface of the insertion hole 20 so that both ends along the circumferential direction of the insertion hole 20 are defined by the lower edge of the main body wall 23 and the arc walls 25. And an insertion hole 20 of the intake collecting chamber 17.
The opening end of the insertion hole 20 is also formed so as to have a peripheral length corresponding to approximately one third of the entire peripheral length of the inner surface of the insertion hole 20.

A rotary valve 26 is inserted into the insertion hole 20 so as to be rotatable around an axis. A part of the rotary valve 26 is provided in each of the intake passages 16A to 16A.
16D, and a part of the rotary valve 26 also enters the intake collecting chamber 17.

The rotary valve 26 is rotated by 120 degrees in accordance with the operation state of the engine. When the rotation speed of the engine is in a low rotation speed range, the rotary valve 26 is shown in FIGS. When the engine speed is in the middle speed range, the rotary valve 26
Rotates to the position shown in FIGS. 5 and 6, and the rotary valve 26 rotates to the position shown in FIGS. 7 and 8 when the rotational speed of the engine is in the high rotational speed range.

First, second, and third regions A1, A in which the structure of the rotary valve 26 is equally divided into three in the circumferential direction.
In the first area A1, a first partition wall 27 disposed on the outer periphery of the rotary valve 26 and facing the inner surface of the insertion hole 20 is provided in the first area A1, as shown in FIGS. When the rotary valve 26 is rotated to a position where the first area A1 corresponds to the opening ends 21 of the intake passages 16A to 16D in the low rotation speed range, the opening ends 21 are closed. On the outer surface of the first partition wall 27, concave portions 28 for forming a part of each of the intake passages 16A to 16D with the opening ends 21 closed by the first partition wall 27 are formed in the respective intake passages 16A to 16D. Is provided corresponding to each of them.

As shown in FIGS. 5 and 6, the rotary valve 26 is positioned at a position where the second region A2 corresponds to the open ends 21 of the intake passages 16A to 16D in the middle rotation speed region of the engine.
Are rotated, the second and third intake passages 16 corresponding to the second and third cylinders whose intake strokes are not continuous with each other.
A communication passage 29 commonly communicating with B and 16C, and a pair of communication passages 30 and 30 respectively communicating with first and fourth intake passages 16A and 16D corresponding to the first and fourth cylinders whose intake strokes are not continuous with each other. , Formed on the rotary valve 26.

The communication passage 29 is formed in the second and third regions A
The second and third intake passages 16 </ b> B, 1 are arranged such that one end is arranged on the outer periphery of the rotary valve 26 at the boundary between the two and A <b> 3, and the other end is connected to the middle part of the first partition wall 27.
6C, a second partition wall 31 provided on the rotary valve 26 at a portion corresponding to the first and second intake passages 16.
A, 16B, and the third and fourth intake passages 16C,
A pair of third partition walls 32, 32 provided at both ends of the second partition wall 31 at a portion corresponding to the area between 16D. In addition, the communication passages 30, 30 are provided with end walls 33, 33 at both ends in the axial direction of the rotary valve 26 and the third partition wall 32,
32.

As shown in FIGS. 7 and 8, the rotary valve 26 is located at a position where the third area A3 corresponds to the open ends 21 of the intake passages 16A to 16D in the high engine speed range.
Is rotated, the communication path 34 that commonly communicates with all of the intake paths 16A to 16B is formed by the second partition wall 3.
The rotary valve 26 on the opposite side of the communication passage 29 with respect to
The two ends of a communication passage 34 along the axial direction of the rotary valve 26 communicate with the communication passages 30, 30, respectively.

Next, the intake control by the rotary valve 26 will be described. When the rotational speed of the engine is in the low rotational speed range, the rotary valve 26 is rotated to the position shown in FIGS. Intake passage 16a
16D are shut off from each other by the first partition wall 27 of the rotary valve 26 and are also cut off from the intake collecting chamber 17, and the intake air in the suction collecting chamber 17 flows through the first to fourth intake passages. The air flows into one of the cylinders 16A to 16D from one end thereof, and is supplied to each cylinder via the first to fourth intake passages 16A to 16D. At this time, the intake air collecting chamber 17 acts as an open-to-atmosphere section, becomes an inversion chamber of the intake pressure vibration, and has a long intake passage 16A to 16A from the combustion chamber of each cylinder to the intake air collecting chamber 17.
It is possible to obtain a high inertia supercharging effect by synchronizing the intake pressure pulsation of the low natural frequency in D with the long opening / closing cycle of the intake valve based on the low rotation speed of the engine, and high in all cylinders. It is possible to obtain the intake charging efficiency and improve the output torque.

Further, since the communication passage 34 of the rotary valve 26 communicates with the intake collecting chamber 17,
Is substantially increased, the function of reversing the intake pressure pulsation in the intake collecting chamber 17 is further increased, a higher inertial supercharging effect is obtained, and the intake charging efficiency and output torque are further improved. be able to.

When the rotation speed of the engine is in the middle rotation speed range, the rotary valve 2 is moved to the position shown in FIGS.
6 is rotated. Thereby, the second and third cylinders corresponding to the second and third cylinders whose intake strokes are not continuous with each other.
The first and fourth intake passages 16B and 16C communicate with each other through a communication passage 29, and the intake strokes are not continuous with each other.
First and fourth intake passages 16A, 16D corresponding to cylinders
Communicate with each other through the communication passages 30 and 30 and the communication passage 34.

As described above, the second and third intake passages 16
B and 16C communicate via the communication passage 29,
The portion of the second and third intake passages 16B and 16C upstream of the communication passage 29 constitutes a resonance system in the second and third cylinders, and the first and fourth intake passages 16A and 16D constitute the communication passage 30. , 30, and 34, the first
And the communication passages 30, 3 of the fourth intake passages 16A, 16D
The portion upstream of 0, 34 constitutes a resonance system in the first and fourth cylinders. Thereby, each of the intake passages 16A to 16D and the communication passages 29, 30, 30, 3
The intake pressure wave generated in one cylinder of the cylinder group in which the intake stroke is not continuous can be transmitted to the next intake stroke of the other cylinder without causing the intake pressure wave to make two rotations inside the cylinder. As a result, a high resonance supercharging effect can be obtained, and high intake charging efficiency can be obtained in each of the first and fourth cylinders in which the intake strokes are not continuous with each other. High intake charging efficiency can be obtained in each of the second and third cylinders, and output torque can be improved. Therefore, in the middle between the low rotation speed region and the high rotation speed region, it is possible to compensate for a valley portion where the intake air charging efficiency and the output torque are reduced.

At this time, the first area A1 of the rotary valve 26 faces the intake collecting chamber 17, and the first partition wall 2
At 7, the intake passages 16 </ b> A to 16 </ b> D and the intake manifold 17 are shut off. That is, the first partition wall 27 functions as a blocking wall that blocks communication between the intake passages 16A to 16D in the low rotation speed region of the engine, and blocks the connection between the intake passages 16A to 16D and the intake collecting chamber 17. It also functions as a wall and can contribute to simplification of the internal structure of the rotary valve 26.

When the rotational speed of the engine is in the high rotational speed range, the rotary valve 2 is moved to the position shown in FIGS.
6 is rotated. As a result, all the intake passages 16
Portions of A to 16D are communicated with each other through a communication passage 34 and communicate with the intake collecting chamber 17 through the communication passages 30 and 30.

As a result, the intake air in the intake collecting chamber 17 is supplied to each of the intake passages 16A to 16D via the rotary valve 26.
And is supplied to each cylinder via a portion downstream of the communication passage 34 in each of the intake passages 16 </ b> A to 16 </ b> D. On the other hand, since the communication passage 34 having a relatively large capacity is also opened to the intake manifold 17, the communication passage 34 and the intake manifold 17 act as an air release part to become a reversal chamber of intake pressure pulsation, and each cylinder In a relatively short distance in each of the intake passages 16A to 16D from the combustion chamber to the communication passage 34, the intake pressure pulsation having a high natural frequency and the short opening / closing cycle of the intake valve based on the high engine speed are synchronized. As a result, a high inertia supercharging effect can be obtained, a high intake charging efficiency can be obtained in all cylinders, and an output torque can be improved.

In this manner, flat high intake air charging efficiency and high output torque can be obtained over a wide rotation speed range from a low rotation speed range to a high rotation speed range of the engine.

Next, the sealing structure between the rotary valve 26 and the intake manifold 15 will be described with reference to FIGS.
0, the insertion holes 20 of the first to fourth intake passages 16A to 16D are formed on the inner surface of the insertion hole 20.
An engagement groove 35 extending in the axial direction of the insertion hole 20 is provided at a position avoiding the open ends 21..., In this embodiment, on the inner surface of a portion formed by the main body wall portion 23 of the insertion hole 20.

A plurality of partition walls 2 provided in the intake manifold 15 so as to sandwich the opening ends 21 to the inner surface of the insertion holes 20 in the middle of the intake passages 16A to 16D.
Are mounted on the outer periphery of the rotary valve 26 at positions respectively corresponding to the positions 2... At a plurality of positions (three positions in this embodiment) spaced in the circumferential direction of the seal rings 36, 36. Seal rings 36, 36 ...
A plurality of seal plates 37 extending in the axial direction of the insertion hole 20 are in contact with the outer periphery of the rotary valve 26.

Mounting grooves 46, 46,... Are provided on the outer periphery of the rotary valve 26 at a plurality of positions corresponding to the partition walls 22 in the intake manifold 15, and the seal rings 36, 36,. Grooves 46, 46 ...
Attached to each.

Each of the seal rings 36 engages with an arc-shaped ring main portion 36a surrounding the rotary valve 26 and an engagement groove 35 of the insertion hole 20 when the ring main portion 36 is mounted on the outer periphery of the rotary valve 26. A pair of arms 36b, 36b projecting from both ends of the ring main portion 36a.
It consists of:

As shown in FIG. 12, a labyrinth passage 47 having a substantially U-shaped cross section is formed between the inner peripheral portion of each seal ring 36 and the mounting groove 46. The labyrinth passage 47 seals the inner periphery of the seal ring 36 and the outer periphery of the rotary valve 26 in the circumferential direction.

The seal plate 37 is formed so as to extend in parallel with the axis of the insertion hole 20 by press molding of a metal plate, hot press molding of a plate made of synthetic resin, injection molding of synthetic resin, or the like. The seal plate 37 is provided with a triangular bead 39 protruding toward the rotary valve 26 so as to contact the outer periphery of the rotary valve 26.

Further, mounting grooves 40 extending in the axial direction of the insertion hole 20 are provided on the inner surface of the insertion hole 20 at portions corresponding to the seal plates 37. Fitting projections 41 fitting to 40 ...
... are provided.

At the portions corresponding to the beads 39 provided on the seal plates 37, the seal rings 36 are provided with:
Beads 43 projecting toward the rotary valve 26 are provided, and beads 39 are provided on the outer periphery of each seal ring 36 so that beads 39 of each seal plate 37 are fitted. Each of the recesses 42 is formed.

Next, the operation of this embodiment will be described. The first to fourth intake passages 1 are provided in the intake manifold 15.
6A to 16D are provided in parallel, and an insertion hole 20 having an axis extending in the direction in which the intake passages 16A to 16D are arranged and opening the middle of each of the intake passages 16A to 16D to the inner surface is provided. The insertion hole 20 has a state in which one end of each of the intake passages 16 </ b> A to 16 </ b> D is commonly connected to a single intake collecting chamber 17 when the rotation speed of the engine is in a low or middle rotation speed range. The rotary valve 26, which can switch the state in which the middle of each of the intake passages 16A to 16D is commonly communicated with the intake collecting chamber 17 when the rotational speed is around the axis of the insertion hole 20, when the rotational speed is in the high rotational speed range. It is movably inserted.

The intake manifold 15 is provided between the rotary valve 26 and the intake manifold 15 such that the open ends 21 of the intake passages 16A to 16D on the inner surface of the insertion hole 20 are interposed therebetween. And a plurality of seal rings 36, 36 attached to the outer periphery of the rotary valve 26 at positions corresponding to the plurality of partition walls 22, respectively, and a plurality of locations spaced apart in the circumferential direction of the seal rings 36, 36 ... The seal rings 36, 36 ...
And a plurality of seal plates 37 extending in the axial direction of the insertion hole 20 so as to be in contact with the outer periphery of the rotary valve 26, and seal rings 36, 36 are provided between the rotary valve 26 and the intake manifold 15.
, And seal plates 37, 37,.

The plurality of seal rings 36, 36,... Mounted on the outer periphery of the rotary valve 26 are pressed by the plurality of seal plates 37, 37, so that the seal rings 36, 36,. While the mounting state is securely held by the seal plates 37, 37,.
Rotary valve 26, a plurality of seal rings 36, 36
... and a plurality of seal plates 37, 37 ...
In this case, the rotary valve 26 can be assembled into the intake manifold 15 by inserting the rotary valve 26 into the intake manifold 15.

Further, the inner surface of the insertion hole 20
Are provided along the axis of the rotary valve 26. Each of the seal rings 36, 36... Has a pair of arms 36b Are formed in an arc shape surrounding the seal ring 36, so that the circumferential positions of the respective seal rings 36, 36,... In the insertion hole 20 can be easily fixed. Further, the rotary valves 26 are provided at positions corresponding to the plurality of partition walls 22 provided on the intake manifold 15 such that the open ends 21 of the intake passages 16A to 16D on the inner surface of the insertion hole 20 are interposed therebetween. Mounting grooves 46, 46,... Are provided on the outer periphery, and each of the seal rings 36, 36.
, Respectively, the positions of the seal rings 36 along the axial direction of the rotary valve 26 can be reliably determined.

Are provided in the inner surfaces of the insertion holes 20 so as to extend in the axial direction of the insertion holes 20 at positions corresponding to the seal plates 37, 37,. Are fitted to the respective seal plates 37, 37 in the circumferential direction of the rotary valve 26.
The position of ... is fixed.

Thus, the seal plates 37, 3
7 and the respective seal rings 36, 36 are fixed and held on the intake manifold 15 side, and the inner periphery of each of the seal rings 36, 36. Plate 3
The sealing in the circumferential direction of the rotary valve 26 is performed at 7, 37..., So that the intake charging efficiency in each cylinder of the multi-cylinder internal combustion engine can be maintained high.

Moreover, the outer periphery of each of the seal rings 36, 36... Is fixed to the intake manifold 15 together with the seal rings 36, 36.
7 are in contact with the inner circumference of the seal rings 36, 3
6 and the labyrinth passages 47 between the mounting grooves 46, 46 suppress intake air leakage between the intake passages 16A to 16D. A seal structure in which the accompanying sliding resistance is suppressed as much as possible can be obtained, the driving torque of the rotary valve 26 can be reduced, and the weight of the variable intake device can be reduced.

Each of the seal plates 37, 37,.
Beads 39, 3 contacting the outer periphery of rotary valve 26
9 are respectively provided, and the respective seal rings 36, 3 are provided.
6 are formed on the outer periphery of each of the seal plates 37, 37 into which the beads 39, 39 of the respective seal plates 37, 37 are fitted, so that the respective seal rings 36, 36 along the circumferential direction of the rotary valve 26 are formed. , And the respective seal rings 37, 37,... And the respective seal plates 37, 37,.
7, 37... Can be mounted on the rotary valve 26, so that the assembling workability can be improved, and each seal plate 37, 37
, The beads 39, 39,... Of the rotary valve 26 are securely brought into contact with each other to reliably suppress the leakage of the intake air in the circumferential direction of the rotary valve 26, so that the intake air charging efficiency can be further improved.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various design changes can be made without departing from the present invention described in the appended claims. It is possible.

For example, in the above-described embodiment, the rotational speed of the engine is set to a low rotational speed region, a medium rotational speed region, and a high rotational speed region.
The rotary valve 26 is rotated in each of the speed ranges in each of the two regions.
The rotation of the rotary valve 26 includes two states, one in which one end of the 6D communicates with the single intake manifold 17 and the other in which the middle of each of the intake passages 16A to 16D communicates with the intake manifold 17. It is also possible to apply the present invention to a variable intake device that is switched according to.

[0047]

As described above, according to the first aspect of the present invention, the assemblability of the rotary valve to the intake manifold can be improved, and the circumferential direction and the axial direction in the insertion hole of each seal ring can be improved. The position is easily and reliably fixed, and the position of each seal plate in the circumferential direction of the rotary valve is fixed, so that each seal plate and each seal ring are fixed to the intake manifold side,
By holding the rotary valve, the rotary valve is reliably sealed in the axial direction and the circumferential direction, so that the intake charging efficiency in each cylinder of the multi-cylinder internal combustion engine can be maintained high. Moreover, the sliding resistance associated with the rotation of the rotary valve can be minimized, the driving torque of the rotary valve can be reduced, and the weight of the variable intake device can be reduced.

According to the second aspect of the present invention, the assembling workability can be improved, and the intake air leakage in the circumferential direction of the rotary valve can be reliably suppressed to further improve the intake charging efficiency. it can.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a rotary valve in a state in which an engine is in a low rotational speed range through an intake manifold.

FIG. 2 is a cross-sectional view of the variable intake device taken along a line 2-2 in FIG. 1;

FIG. 3 is an enlarged view of a main part of FIG. 2;

FIG. 4 is a transverse sectional view corresponding to FIG. 3 and taken along a line 4-4 in FIG. 1;

FIG. 5 is a perspective view corresponding to FIG. 1 in a state where the engine is in a middle rotation speed range.

6 is a cross-sectional view corresponding to FIG. 3 in a state where the engine is in a middle rotation speed range.

FIG. 7 is a perspective view corresponding to FIG. 1 in a state where the engine is in a high rotation speed range.

FIG. 8 is a cross-sectional view corresponding to FIG. 3 in a state where the engine is in a high rotation speed range.

FIG. 9 is an exploded perspective view of a rotary valve, a seal ring, and a seal plate.

FIG. 10 is an enlarged sectional view taken along line 10-10 of FIG. 4;

[Explanation of symbols]

 15 ... intake manifold 16A, 16B, 16C, 16D ... intake passage 17 ... intake collecting chamber 20 ... insertion hole 21 ... open end 22 ... partition 26 ... rotary valve 35 ... engagement groove 36 ... seal ring 36b ... arm 37 ... seal plate 39 ... bead 40 ... mounting groove 41 ... fitting projection 42 ... concave 46 ..Mounting grooves

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Yoshiyuki Unno 1-4-1 Chuo, Wako-shi, Saitama Pref. Honda Research Institute, Inc. (72) Inventor Kazuhito Kakimoto 1-4-chuo Chuo, Wako-shi, Saitama No. 1 In Honda R & D Co., Ltd. (72) Inventor Yasushi Matsuura 1-4-1 Chuo, Wako-shi, Saitama F-term in R & D Co., Ltd. F-term (reference) 3G031 AA28 AB05 AC01 BA07 BA14 BA17 BA18 BB02 DA25 DA34 FA03 GA06 GA07 GA08 HA01 HA08 HA10 3J040 AA01 AA13 AA17 BA07 CA04 EA05 EA18 EA25 FA01 HA03 HA05 HA15 HA20

Claims (2)

[Claims] 1. A plurality of intake passages (16A, 16B, 1) arranged in parallel corresponding to respective cylinders of a multi-cylinder internal combustion engine.
6C, 16D) and their intake passages (16A to 16A).
An insertion hole (20) having an axis extending in the arrangement direction of D) and opening an intermediate portion of each of the intake passages (16A to 16D) to the inner surface is provided in the intake manifold (15), and each of the intake passages (16A to 16D) is provided. 16D), a state in which one end of each of the intake passages (16A to 16D) is commonly communicated with the intake manifold (17), and a state in which one end of the intake passage is commonly communicated with the single intake manifold (17). (2
In the variable intake device for a multi-cylinder internal combustion engine, a rotary valve (26) that can be switched in accordance with rotation about the axis of 0) is rotatably inserted into the insertion hole (20). An engagement groove (35) extending along the axis of the insertion hole (20) is provided on the inner surface of the insertion hole (2).
Positions corresponding to the plurality of partition portions (22) provided in the intake manifold (15) such that the opening ends (21) in the middle of the intake passages (16A to 16D) on the inner surface of the intake manifold (15) are interposed therebetween. In the rotary valve (26)
A mounting groove (46) is provided on the outer periphery of the engagement groove (3).
5) An arc-shaped seal ring (36) having a pair of arms (36b) at both ends and surrounding the rotary valve (26) is mounted in the mounting groove (46), respectively. A plurality of seal plates (37) extending in the axial direction of the insertion hole (20) so as to be in contact with the outer periphery of the seal ring (36) and the rotary valve (26) at a plurality of locations spaced in the circumferential direction of (36). The insertion holes (2) extend in the axial direction of the insertion holes (20) at positions corresponding to the seal plates (37).
A rotary valve seal structure in a variable intake device for a multi-cylinder internal combustion engine, wherein a fitting projection (41) is fitted to a mounting groove (40) provided on the inner surface of (0). 2. A bead (3) contacting an outer periphery of a rotary valve (26) is provided on each of said seal plates (37).
9) are respectively provided, and the respective seal rings (36) are provided.
Around the bead (3) of each seal plate (37)
The seal structure of a rotary valve in a variable intake device for a multi-cylinder internal combustion engine according to claim 1, wherein concave portions (42) for fitting the respective components (9) are formed.