JPH0137152Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the structure of an intake manifold for an automobile engine, and particularly to the structure of an intake manifold having two intake ports for each cylinder.

Conventionally, each cylinder had two intake ports, and one intake port was equipped with an intake air control valve.
2. Description of the Related Art Intake manifolds are known in which intake air control valves are opened and closed in accordance with engine speed. (For example, JP-A-57-
No. 105534). In such an intake system, the intake air control valve is closed in the low to medium speed range of the engine, and air is exclusively taken in through the intake port that is not equipped with an intake air control valve out of the two intake ports, and the intake air flow rate is increased. is appropriately large to maintain good combustion and torque performance within the combustion chamber. In addition, when the engine is in a high speed range, the intake air control valve is opened and air is taken in through the two intake ports, increasing the amount of intake air and increasing the engine output.

The intake air control valve is opened and closed by rotating an intake air control valve shaft to which the intake air control valve is mounted using an actuator. In the structure of the conventional intake air control valve,
As seen in No. 105534, the intake air control valve shaft consists of a single shaft extending in the longitudinal direction of the engine.
All of the twice as many intake ports were penetrated from one end to the other. The actuator was disposed on one side of the intake ports arranged in parallel, and was connected to the intake air control valve shaft via a link or the like.

However, in such a conventional structure, since the intake air control valve shaft passes through the intake port, the cross-sectional area of the port decreases, the amount of intake air decreases, and the engine output decreases accordingly.

In order to solve the above problem, that is, to suppress the reduction in the port cross-sectional area of the intake port due to the intake air control valve shaft, the applicant first developed an intake system in which each cylinder is provided with two intake ports. It has an air control valve body, and an intake air control valve is installed in one of the two intake ports,
The intake air control valve is opened and closed by an actuator, the actuator is disposed at the center of the intake air control valve body in the longitudinal direction of the engine, and the intake air control valve shaft rotated by the actuator is connected to the intake air control valve. An intake air control valve structure has been proposed that extends from the center of the valve body toward both ends to a position immediately in front of the intake ports at both ends, eliminating the structure in which the intake air control valve shaft penetrates the intake ports at both ends.

In such a device, by eliminating the intake air control valve shafts of the intake ports at both ends, the port cross-sectional area of the intake ports at both ends is increased, and an increase in engine output is obtained. However, on the other hand, there is a difference in intake resistance due to the presence or absence of the shaft penetration between the intake port through which the intake air control valve shaft penetrates and the intake port through which it does not penetrate, resulting in a new problem of poor intake air distribution.

This invention eliminates the intake air control valve shaft penetration structure in some intake ports, thereby increasing engine output, and suppressing variations caused by the presence or absence of the intake air control valve penetration, thereby improving the air-fuel mixture distribution. The purpose is to make improvements.

The intake manifold of the present invention that meets this purpose is provided with two intake ports for each cylinder, and an intake air control valve in one of the two intake ports, and the intake air control valve is connected to the intake manifold. An actuator disposed in the center opens and closes the intake air control valve shaft through an intake air control valve shaft that extends from the center toward the intake ports at both ends and passes through intake ports other than the intake ports at both ends. The intake port has a structure in which the length of the intake pipe of the intake port that is not open is longer than the length of the intake pipe of the intake port that the intake air control valve shaft passes through.

With this configuration, the difference in ventilation resistance between the intake port that the intake air control valve shaft penetrates and the intake port that does not penetrate is reduced due to the difference in intake pipe length, and the air flow to each cylinder is reduced. The mixture is evenly distributed. Moreover, the shaft penetrating structure at both end intake ports is improved by the central arrangement structure in the intake manifold of the actuator and the structure that passes through the intake ports other than the both end intake ports from the center of the intake air control valve shaft toward the both end intake ports. It can be abolished, and the effect of increasing the engine output by increasing the port cross-sectional area can be maintained.

Preferred embodiments of the structure of the intake manifold of the present invention will be described below with reference to the drawings.

FIG. 1 shows the structure of the vicinity of the intake manifold of an engine equipped with the intake manifold according to the present invention. In the figure, 1 is the main body of the engine, and each cylinder 2 has two intake ports 3, 4 and two exhaust ports 5.
It consists of a valve engine. An intake air control valve 7 is disposed in one of the two intake ports 3 and 4 provided for each cylinder, so that the intake port 3 can be opened and closed. The other intake port 4 is not provided with an intake air control valve 7. Intake ports 3 and 4 of the engine body 1 are connected to a surge tank 6 via an intake air control valve body 9 and an intake manifold 100. Intake air control valve body 9 and intake manifold 100
are intake ports 3 and 4 connected to intake ports 3 and 4 of the engine body 1, respectively.
have. And intake ports 3 and 4
are joined together at the surge tank 6.

The intake ports 3 and 4 of the engine body 1 communicate with each other downstream of an intake air control valve 7 in the engine body 1 portion, and an injection nozzle 8 of an electronically controlled fuel injection device is provided in the communication portion. The injection nozzle 8 is configured to inject a large amount of fuel into the intake port 3 on the side where the intake air control valve 7 is provided.
It is arranged at a slightly shifted position on the intake port 3 side. The intake air control valve 7 is attached to an intake air control valve body 9 formed separately from the engine body 1, and this is attached to the engine body 1.

2 and 3 show the structures of the intake air control valve 7 and the intake air control valve body 9. FIG. Intake air control valve body 9 as shown in the figure
The engine is equipped with two intake ports 3 and 4 for each cylinder, and as described above, one of the intake ports 3 is equipped with an intake air control valve 7. The intake air control valve body 9 has a two-part configuration in which it is divided into two parts at the center in the longitudinal direction of the engine, and each of the divided intake air control valve body halves 9a and 9b are connected to each other. There is.

An actuator 12 for opening and closing the intake air control valve 7 is disposed at the center of the intake air control valve body 9 in the longitudinal direction of the engine. This actuator 10 is provided between the intake air control valve body halves 9a and 9b, and by dividing the intake air control valve body 9 into two parts, a central arrangement structure can be easily achieved.

The intake air control valve shaft rotated by the actuator 10 is a pair of separately formed shafts 11a and 11b that extend in the longitudinal direction of the engine and are divided at the center of the intake air control valve body 9.
Consists of. Of these, the intake air control valve shaft 11a is provided on the intake air control valve body half 9a, and the intake air control valve shaft 11b is provided on the intake air control valve body half 9b.
established in The pair of intake air control valve shafts 11a and 11b are connected to intake ports 4a and 4b located at both ends of the intake ports 3 and 4 arranged in parallel from the center of the intake air control valve body 9 toward both ends. It extends to the position immediately before . The intake ports 4a, 4b at both ends consist of intake ports 4a, 4b in which the intake air control valve 7 is not disposed, and the intake air control valve shafts 11a, 11b do not penetrate through the intake ports 4a, 4b at both ends. If it wasn't there, it wouldn't have entered.

Intake air control valve shaft 1
1 is installed from the center of the intake air control valve body 9 toward both ends.
It is formed in a straight line up to a position immediately in front of the intake ports 4a and 4b at both ends, and when the intake air control valve body 9 is in a half-split state, a hole is formed in a straight line from the center side of the intake air control valve body. Intake air control valve shaft 11 shown in Figures 4 to 6
a, 11b are inserted. The portion between the adjacent intake ports 3 and 4 of the intake air control valve body 9 becomes a bearing portion 12 that supports the intake air control valve shaft 9, and the journal portion 13 of the intake air control valve shaft 11 is attached to the bearing portion 12. Rotatably fitted.

Intake air control valve shaft 1
1 passes through the intake ports 3 and 4 except for the intake ports 4a and 4b at both ends, but among these, the portion that passes through the intake port 3 where the intake air control valve 7 is to be installed has an intake air control valve. Valve 7 is installed. To attach the intake air control valve 7 to the intake air control valve shaft 11, as shown in FIG. The disk-shaped intake air control valve 7 is placed on the plane portion 15 extending on the diameter of the semicircular cross section, and the screw 16 is inserted.
This is done by fixing it in place.

Intake air control valve shaft 1
1, a portion 17 that passes through the intake port 4 (excluding the intake ports 4a and 4b at both ends) where the intake air control valve 7 is not installed.
As shown in FIG. 6, the diameter is smaller than that of other parts. This diameter reduction is done in order to reduce the intake resistance within the intake port 4.

On the other hand, an actuator 10 disposed in the center of the intake air control valve body 9
3, integrally includes a bracket 18 extending on both left and right sides toward the intake air control valve body halves 9a, 9b on both sides. Then, by fixing this bracket 18 to the intake air control valve body halves 9a, 9b with screws 19, the pair of intake air control valve body halves 9a, 9b are integrated, and the intake air control valve body 9
Configure. Further, a second intake air control valve body is provided between the pair of intake air control valve body halves 9a and 9b.
As is particularly clearly shown in the figure, a knock pin 20 is provided extending between the two and having both ends press-fitted into holes formed in the intake air control valve body halves 9a and 9b, respectively. The knock pin 20 also allows the intake air control valve body halves 9a, 9
b are positioned and integrally fixed to each other.
This knock pin 20 also functions as a full-open stopper for regulating the full-open position when opening and closing the intake air control valve 7.

The actuator 10 also has intake air control valve shafts 11a, 11b and a seventh
They are connected as shown in FIG. That is, a rod 21 extends from the actuator 10. The rod 21 is connected to an intake air control valve shaft 11 fixed to one intake air control valve shaft 11a.
A pin 23 is attached to the first lever 22 that rotates together with a.
are connected via. A second lever 24 is attached to the other intake air control valve shaft 11b so as to rotate together with the intake air control valve shaft 11b. First lever 22 and second lever 24
The leaf spring 25 is designed to allow slight relative rotation and is attached to the first lever 22.
presses the pin 26 attached to the second lever 24, so that the first lever 22 always urges the second lever 24 to rotate in the direction to close the intake air control valve 7. is connected to. Therefore, the actuator rod 21 rotates the first lever 22 to rotate the intake air control valve shaft 11a, and the first lever 22 rotates the leaf spring 25 and the pin 2.
6. Rotate the second lever 24 to rotate the intake air control valve shaft 11b. In FIG. 7, reference numerals 20 and 27 are a full-open stopper and a full-close stopper, respectively, which regulate the fully open and fully closed positions of the intake air control valve 7. Reference numeral 28 is an adjustment screw that can adjust the position of the fully closed stopper 27, and 29 is a locking spring.

Intake negative pressure is introduced to the actuator 10 .
In FIG. 2, one of the intake ports 3 is provided with a negative pressure outlet 30, and the negative pressure outlet 30 communicates with a negative pressure tank (not shown) and the atmosphere controlled by a computer. It is connected to the negative pressure supply port 31 of the actuator 10 via a three-way solenoid valve. The computer opens and closes the intake air control valve 7 according to the engine speed by controlling the opening and closing of the solenoid valve.

In the intake manifold 100 interposed between the intake air control valve body 9 and the surge tank 6, among the intake ports 4 to which the intake air control valve 7 is not installed, the intake ports 4a, 4b at both ends,
That is, the intake port 4a through which the intake air control valve shaft 11 does not pass,
The intake pipe length of 4b is the intake port 4 on the center side.
c, 4d, that is, the length is longer than the intake pipe length of the intake ports 4c, 4d through which the intake air control valve shaft 11 passes. Intake ports 4a and 4b at both ends
are largely curved and spread in the longitudinal direction of the engine, and the central intake ports 4c and 4d have a small degree of curvature. The intake ports 4a and 4b at both ends are bent to the extent that they curve and expand.
The intake pipe length is increased.

In addition, 32 is a crest valve provided upstream of the surge tank 6.

Next, the operation of the structure of the intake manifold configured as described above will be explained.

Intake air from the surge tank 6 passes through the intake manifold 100, the intake air control valve body 9, and the intake ports 3 and 4 formed in the engine body 1, and fuel is injected from the injection nozzle 8, and the mixture enters the combustion chamber. is inhaled. The opening and closing of the intake air control valve 7 attached to the intake port 3 is controlled by controlling the operation of an actuator 10 by opening and closing a solenoid valve by a computer. That is, the intake air control valve 7 is closed in the low and medium speed range of the engine, and the intake air control valve 7 is opened in the high speed range of the engine. This opening/closing control maintains good torque performance in low and medium speed ranges, secures output in high speed ranges, and achieves the original function of the intake air control valve 7.

In the structure of such an intake air control valve, whereas conventionally the shaft penetrated through all the intake ports, the structure where the shaft 11 penetrates the intake air control valve shaft 11 at both ends of the intake ports 4a and 4b has been abolished. There is. Therefore, the port cross-sectional area of the intake ports 4a, 4b at both ends is increased accordingly, the amount of intake air taken in is increased, and the engine output is increased. Especially the intake port 4a,
4b is a port through which intake air flows throughout the low, medium and high speed ranges of the engine, and the engine output is increased over all speed ranges.

Further, since the intake air control valve shaft 11 is not present in the intake ports 4a and 4b at both ends, no intake resistance is generated by the intake air control valve. Therefore,
The engine output increases by that amount compared to the conventional structure.

In addition, the intake ports 4a and 4b at both ends are connected to an intake manifold 100, as shown in FIG.
Central intake ports 4c and 4d in the area
Since the pipe structure is more curved, the resistance increases accordingly, but since there is no intake air control valve shaft, the resistance decreases, so they cancel each other out and equalize the flow path resistance to each cylinder. , the distribution of air-fuel mixture in each cylinder becomes uniform. Fuel efficiency also improves through improved air-fuel mixture distribution.

Further, regarding the reduction in intake resistance, the diameter reduction of the intake port 4 penetration portion 17 of the intake air control valve shaft 11 also contributes.

Additionally, the centrally disposed structure of the actuator 10 in the intake air control valve body 9 further facilitates smooth and accurate operation of the intake air control valve 7. In the conventional structure where the actuator is placed at one end of the parallel intake ports and the rotation stopper is placed at the other side, a large torsional force from the actuator is applied to the intake air control valve shaft.
Due to the twist of the shaft, the opening and closing positions of each intake air control valve shift, making it difficult to ensure smooth and accurate valve opening and closing. However, in the device of this embodiment, the torsional force applied to the intake air control valve shaft 11 is only the opening/closing force that the intake air control valve 7 receives from the intake flow, and this torsional force is not essentially large, so the intake air control valve shaft 11 The opening and closing of the valve 7 becomes much smoother.

As explained above, when using the intake manifold structure of the present invention, the actuator is arranged in the center of the intake air control valve body, the intake air control valve shafts at the intake ports at both ends are eliminated, and the intake manifold Among the ports, the intake pipe length of the intake port that the intake air control valve shaft does not penetrate is made longer than the intake pipe length of the intake port that the shaft penetrates, increasing the engine output by increasing the port cross-sectional area and reducing intake resistance. In addition, it is possible to equalize the intake resistance of each intake port and improve the air-fuel mixture distribution.

[Brief explanation of the drawing]

Fig. 1 is a plan view of an engine intake system with a part of the intake manifold structure according to an embodiment of the present invention shown in cross section, and Fig. 2 is a front view of the intake port and its vicinity in the first embodiment. , Fig. 3 is a plan view of the device shown in Fig. 2, Fig. 4 is a plan view of the intake air control valve shaft and the intake air control valve, Fig. 5 is a sectional view taken along the - line in Fig. 4, and Fig. 6. is - in Figure 4
7 is a side view of the actuator and its vicinity; FIG. 8 is a plan view of the device shown in FIG. 7;
It is. 1... Engine, 2... Cylinder, 3, 4... Intake port, 4a, 4b... Intake port through which the intake air control valve shaft does not pass, 4c, 4d... Intake port through which the intake air control valve shaft passes. 7...Intake air control valve,
9...Intake air control valve body, 10...Actuator, 11...Intake air control valve shaft, 17...Reduced diameter portion, 18...Bracket, 100...Intake manifold.

Claims (1)

[Scope of utility model registration request] Two intake ports are provided for each cylinder, and an intake air control valve is provided in one of the two intake ports, and the intake air control valve is operated from the center by an actuator disposed in the center of the intake manifold. The intake air control valve opens and closes via the intake air control valve shaft that extends toward the intake ports at both ends and passes through the intake ports other than the intake ports at both ends, and controls the length of the intake pipe of the intake port through which the intake air control valve shaft does not pass. The structure of the intake manifold is characterized by being longer than the intake pipe length of the intake port through which the valve shaft passes.