JPS5910345Y2 - engine intake system - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement in an intake system in which an on-off valve is provided in each intake pipe of an intake manifold communicating with each cylinder of a multi-cylinder engine.

Many intake manifolds of multi-cylinder engines are equipped with an on-off valve for each intake pipe.

For example, a partition wall is provided in the intake pipe to form a high-load intake passage and a low-load intake passage, and an on-off valve is provided in the high-load intake passage.During high-load operation, the on-off valve is opened and both are separated. This is the so-called dual induction method, which takes air through the intake passage, and during low-load operation, closes the on-off valve and uses only the low-load intake passage, which tends to generate swirl, to improve combustibility during low-load operation. This includes an intake system or an engine intake system in which the number of air intakes is controlled by controlling an on-off valve (shutter valve) provided in each intake pipe.

Such an on-off valve is normally operated via a shaft rotatably held in the intake manifold, in conjunction with a carburetor, or by a separately provided actuator.

Recently, various intake devices have been proposed in which the shaft is constructed by connecting a plurality of shafts, taking into consideration the ease of assembling the shaft to the intake manifold (for example, An example thereof is disclosed in Japanese Patent No. 55-139923).

When dividing the shaft as shown above, the divided parts (
The connecting part) is often exposed outside the intake manifold for shaft connection work, but if this divided part is exposed to the atmosphere, the intake manifold can be removed from the gap between the exposed shaft and the shaft support. This causes the problem of air entering the interior.

For this reason, it is conceivable to seal the divided portions with a sealing material, but such sealing increases the cost of the intake device and requires a separate operation to assemble the sealing material, which is not preferable.

The present invention was conceived in view of the above circumstances, and is an engine intake air intake system that can prevent atmospheric air from entering the intake manifold from the split portion of the on-off valve shaft without using a separate sealing material. The purpose is to provide a device.

The engine intake system of the present invention has an intake manifold that includes
It is characterized in that it has a bag-like recess in which the divided portion of the shaft is located, and that the recess is covered by the wall surface of the cylinder head to which the intake manifold is connected.

In the engine intake system of the present invention having the above structure, when the intake manifold is attached to the cylinder head,
The shaft split portion is automatically isolated from the atmosphere.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an engine intake system according to one embodiment of the present invention.

A cylinder head 2 is attached to a cylinder block 1 of an in-line four-cylinder cylinder, and a combustion chamber 5 is defined by pistons 1 to 4 which are slidably fitted into the cylinder block 1, cylinder head 2, and cylinder bore 3. has been done.

The cylinder head 2 is formed with a low-load intake port 6 and a high-load intake port 7 that open into the combustion chamber 5, respectively.

The low-load intake port 6 is located below the high-load intake port 7 and is oriented substantially horizontally with respect to the combustion chamber 5, so as to generate a strong intake swirl within the combustion chamber 5. It has become.

In addition, the high-load intake port 7 is set to have a larger effective opening area than the low-load intake ports 1 and 6 so that a sufficient amount of air-fuel mixture can be taken in, and the combustion chamber is designed to reduce intake resistance. 5, it is set to face approximately in the axial direction thereof.

An intake manifold 8 is connected to the cylinder head 2,
Each intake pipe 9 corresponds to each part of this intake manifold 8.
is connected to the low load intake port 6 at its downstream end.
It has a low-load intake pipe 9a that communicates with the high-load intake port 7, and a high-load intake pipe 9b that communicates with the high-load intake port 7.

Of course, each intake pipe 9 has a gathering part 10 on its upstream side,
It is connected to other intake pipes.

A butterfly-type on-off valve 11 is provided in each of the high-load intake pipes 9b.

The structure around this on-off valve 11 is shown below in Figures 2 and 3.
This will be explained in detail with reference to the figures, but in Figs. 2 and 3,
A number from "-1" to "4" is added to each cylinder to distinguish the component numbers from each other.

Opening/closing valves 11-1 for the first cylinder and the second cylinder. 11-2
are screwed onto the shaft 12, and the on-off valves 11-3 and 11-4 for the third and fourth cylinders are screwed onto the shaft 12.
2 is screwed onto a shaft 13 provided separately.

Shaf} 12. 13 is rotatably held by the intake manifold 8 and arranged in series on the axis 1 parallel to the intake manifold mounting surface 2 a of the cylinder head 2 .

On the cylinder head mounting surface 8a of the intake manifold 8,
A bag-shaped recess 14 is formed between the second cylinder intake pipe 9-2 and the third cylinder intake pipe 9-3.

When the intake manifold 8 is attached to the cylinder head 2 via the gasket A, the opening of the recess 14 is covered by the intake manifold mounting surface 2a of the cylinder head 2, and the recess 14 is automatically isolated from the atmosphere. Ru.

In this recess 14, one end 12 of the shaft 12 is provided.
a is extended, and one end 13a of the shaft 13 is also extended.

And these shafts 12. 13 each one end 12 a
, 13a are integrally rotatably connected by an Oldham joint.

That is, the intermediate piece 20 of the Oldham joint disposed between both shafts H2.13 has a groove 2 extending in the radial direction on one end surface thereof.
0a, and one end 12a of the shaft 12 facing the groove 20a has a protrusion 1 extending in the radial direction.
2b are formed, and these grooves 20a and projections 12b are slidably fitted into each other.

Further, the other end surface of the intermediate piece 20 is formed with a groove 20b extending in the radial direction perpendicular to the groove 20a, and the one end 13a of the shaft 13 is formed with a protrusion 13b. 20b and the protrusion 13b are slidably fitted into each other.

Here, the support hole 15 of the intake manifold 8 that holds the shaft 12 is formed by, for example, drilling, and the opening on the C side of the other end 12 of the shaft 12 is formed by a blind plug 1.
6 is occluded.

Further, the support hole 17 into which the shaft 13 is fitted is similarly shaped by drilling, etc., but the opening on the C side of the other end 13 of the shaft 13 is not closed, and the shaft 13 is allowed to flow out of the intake manifold 8. It's been extended.

An arm 18 is coupled to the other end 13C of the shaft 13, and the arm 18 is connected to the slot valve (
(not shown).

Shuff as described above} 12. 13 On-off valve 11-1~
11-4 may be assembled, for example, as follows.

Before attaching the intake manifold 8 to the cylinder pedestal 2, first assemble the shaft 12 to the intake manifold 8 in the X direction in FIGS.
On-off valves 11-1 and 11-2 are attached to 2, and a blind plug 16 is attached.

Further, after assembling the shaft 13 to the intake manifold 8 from the Y direction in FIGS. 2 and 3, it is connected to the shaft 12 by the intermediate piece 20 of the Oldham joint, and
．． Install 11-4.

After this, the intake manifold 8 may be attached to the cylinder head 2.

When the intake manifold 8 is attached to the cylinder head 2, the shaft l-12. A recess 14 formed for connecting the shafts 13 is closed by the cylinder head 2 as described above, and the shaft 1 projects into the recess 14.
2 and 13 are isolated from the atmosphere, so that the atmosphere is not sucked in between the shafts 12 and 13 and the support holes 15 and 17.

The shafts 12 and 13 are positioned in the axial direction by attaching on-off valves 11-1 to 11-4, and are rotated together via Oldham joints.

In addition, the slight deviation of the axes of both shafts H2 and H13 is absorbed by the Oldham joint, and both shafts} 12. 13 rotate smoothly and integrally.

In the intake system having the above structure, the on-off valve 11-1
to 11-4 are linked to the throttle valves 1 to 11-4 to close the high-load intake pipes 9b-1 to 9b-4 when the load is low.

Therefore, the air-fuel mixture flows only through the low-load intake ports 6-1 to 6-4 from the low-load trachea 9a1 to 9a-4, and is supplied to the combustion chamber 5.

As a result, swirl generation is strengthened and combustibility at low loads is improved.

Also, when the load is high, the on-off valves 11-1 to 11-4 are opened,
The air-fuel mixture is supplied to the combustion chamber 5 from both the low-load intake ports 6-1 to 6-4 and the high-load intake ports 7-1 to 7-4, and the filling amount is smoothly increased.

The embodiments in which the present invention is applied to a dual induction type intake system have been described above.The present invention provides an on-off valve in each intake pipe of the intake manifold, and changes the number of cylinders in use by controlling the on-off valve. The present invention is applicable to all intake systems in which an on-off valve is provided in each intake pipe of an intake manifold, such as an intake system for a so-called variable cylinder engine.

Further, as a means for connecting the plurality of divided shafts, it is of course possible to use something other than the Oldham joint in the above embodiment.

In addition to mechanically interlocking the opening/closing valve with the throttle valve as in the above embodiment, it is of course possible to operate the opening/closing valve by an actuator or the like controlled by intake pipe negative pressure, exhaust pressure, or the like.

As explained in detail above, the engine intake system of the present invention can prevent atmospheric suction by shielding the shaft support part exposed at the shaft division part from the atmosphere without using a special sealing member. This is extremely preferable in terms of improving adhesion and reducing costs.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view showing one embodiment of the present invention, Fig. 2 is a sectional view taken along line II-III in Fig. 1, and Fig. 3 is a sectional view taken along line III in Fig. 2.
-III line sectional view. 2... Cylinder head, 2a... Intake manifold mounting surface, 8... Intake manifold, 9... Intake pipe,
9b-1 to 9b-4...High load intake pipe, 11-1 to
11-4...Opening/closing valve, 12, 13...Shaft 1~
, 14... recess, 20... (Oldham joint) intermediate piece.

Claims (1)

[Scope of utility model registration request] An engine characterized in that a bag-shaped recess is formed in the manifold wall at a divided portion of a shaft that supports an on-off valve provided in each intake pipe of the intake manifold, and the opening of the recess is covered by the cylinder head wall. intake device.