JPH0725230U - Engine intake system - Google Patents

Abstract

(57) [Summary] [Purpose] To provide an intake device for an engine capable of generating a strong tumble flow in a cylinder. A tumble control valve 13 that generates a deflected flow for generating a tumble flow in an intake passage 10a of an injector holder 10 that is continuous with the intake port 6, and a section that maintains the generated deflected flow and guides it to the inlet of the intake port. An intake device for the engine provided with the wall 14.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an intake system for an engine capable of generating a strong tumble flow in a cylinder by maintaining a deflected flow of intake air by a tumble control valve.

[0002]

[Prior art]

 In the engine operating range, where the throttle opening is small and the intake air volume is small accordingly, in the low load range, the air-fuel mixture is generally set to be slightly rich to stabilize combustion, which results in better fuel economy and emissions. It tends to get worse. As a measure to improve fuel consumption and emissions, it is effective to generate a swirl flow in the intake air in the cylinder to promote combustion by strong turbulence. Conventionally, a lateral swirl flow or vertical swirl (tumble) is applied to the intake air. Various techniques for generating a flow are known.

Here, the lateral swirl flow swirls the intake air along the peripheral wall of the cylinder, and has a high effect of uniforming the intake air, but has a low effect of promoting combustion due to turbulent flow generation. On the other hand, the tumble flow swirls intake air along the axial direction of the cylinder, and the tumble flow collapses in the latter half of the compression stroke to generate strong turbulence, which improves combustion in the low engine load region. It is effective as a measure.

Such a tumble flow is generated when intake air passing through the intake port is sucked into the cylinder as a deflected flow along one wall surface of the intake port, that is, along the wall surface near the exhaust port. Therefore, it has been conventionally proposed to install a tumble control valve that supplies intake air as a deflected flow into the intake port in the intake passage upstream of the intake port (see Japanese Patent Laid-Open No. 58-124019).

[0005]

[Problems to be solved by the device]

 By the way, in the prior art described in the above publication, since the intake passage between the tumble control valve and the inlet of the intake port is only one passage, the deflected flow of intake air generated by the tumble control valve is also generated in the intake port. It weakens by the time it reaches the entrance. For this reason, the deflected flow of the intake air passing through the intake port becomes weak, and it cannot be expected to generate a strong tumble flow in the cylinder.

Therefore, an object of the present invention is to provide an intake device for an engine capable of generating a strong tumble flow in a cylinder.

[0007]

[Means for Solving the Problems]

 To this end, the present invention provides an intake system for an engine, which includes an intake passage connected to an intake port of the engine and an injector holder connected to a cylinder head having an injector mounting portion for injecting fuel into the intake port. In the intake passage of the injector holder, a tumble control valve that generates a deflection flow for generating a tumble flow, and a partition wall that maintains the deflection flow generated by the tumble control valve and guides it to the inlet of the intake port. Is provided as a means.

Here, in the present invention, the partition wall is extended to the inside of the inlet of the intake port, the tumble control valve is provided on the upstream side of the partition wall, and the tumble control valve is divided into two by the partition wall. The butterfly valve has a cutout on one side of the intake passage.

[0009]

[Action]

 In the intake system for an engine according to the present invention which employs such means, a deflecting flow for generating a tumble flow is generated in the intake passage of the injector holder by the operation of the tumble control valve, and this deflecting flow is directly maintained by the partition wall. It is maintained and guided to the inlet of the intake port. For this reason, a strong bias flow flows as a deflection flow for generating the tumble flow in the intake port, and a strong tumble flow is generated in the cylinder.

Since the tumble control valve is provided in the intake passage in the injector holder that is continuous with the intake port, the distance between the tumble control valve and the intake port inlet is short, and the deflection flow for generating the tumble flow is small. Is supplied to the intake port without inadvertently weakening.

Further, since the tumble control valve and the partition wall are provided inside the injector holder, they can be easily applied to an existing engine by changing only the injector holder.

[0012]

【Example】

 Hereinafter, one embodiment of the present invention will be described in detail with reference to the accompanying drawings. In FIG. 1A showing the overall schematic structure of an engine intake device according to one embodiment, reference numeral 1 indicates an engine body 1 in which a cylinder head 3 is assembled to a cylinder block 2, and an intake valve 4 is attached to the cylinder head 3. An intake port 6 communicating with the combustion chamber 5 via the exhaust port 8 and an exhaust port 8 communicating with the combustion chamber 5 via the exhaust valve 7 are formed. An ignition plug 9 is installed in the center of the combustion chamber 5.

An injector holder 10 made of an aluminum alloy is connected to the cylinder head 3 and has an intake passage 10 a continuous with the intake port 6 and a mounting portion 10 b of an injector 11 for injecting fuel into the intake port 6. An end of the intake manifold 12 is connected to the holder 10.

A tumble control valve 13 is installed in the intake passage 10a of the injector holder 10, and a partition plate 14 as a partition wall extending from the position of the tumble control valve 13 toward the intake downstream side. Is integrally formed with the injector holder 10 by an aluminum die casting method.

The tumble control valve 13 is a butterfly valve having a notch 13a as shown in FIG. 1 (b), and the tumble control valve 13 is drive-controlled by an engine control unit (not shown) so that the tumble control valve 13 is opened in a low load region of the engine. The notch 13a faces the wall surface side 10c of the intake passage 10a, that is, the wall surface side 10c continuous to the wall surface side 6a of the intake port 6 near the exhaust port 8, and the intake passage 10a is partially opened to close the engine. In the high load region, the intake passage 10a is fully opened.

Further, the partition plate 14 divides the intake passage 10a into a first passage 10d on one side 10c of the wall surface and a second passage 10e on the opposite side and divides the suction port from the center of rotation of the tumble control valve 13. 6 extends to the vicinity of the inlet, that is, to the same plane as the joint surface 10f with the cylinder head 3. The injector 11 is attached to the attachment portion 10b located on the side of the first passage 10d thus divided.

Next, the operation of the intake system for an engine according to this embodiment having the above-described structure will be described. In the low load region of the engine, the tumble control valve 13 is in a state in which only the wall surface side 10c of the intake passage 10a in the injector holder 10 is partially opened by drive control of an engine control unit (not shown). Therefore, the intake air flowing from the intake manifold 12 into the intake passage 10a of the injector holder 10 during the intake stroke of the engine with the intake valve 4 opened becomes a deflected flow along the wall surface side 10c. The deflected flow passes through the relatively short first passage 10d partitioned by the partition plate 14 from the second passage 10e, so that the deflected flow is not inadvertently weakened in the intake port 6 along the wall surface side 6a. Is sucked in, and thus a strong biased flow for generating the tumble flow is generated in the intake port 6.

On the other hand, when the fuel is injected from the injector 11 into the intake port 6, a mixture is formed in the strongly deflected flow that is sucked along the wall surface one side 6a in the intake port 6, As the air-fuel mixture is sucked into the cylinder 16 along the cylinder wall surface on the exhaust port 8 side as the arrow of FIG. A tumble stream is produced.

Then, the tumble flow of the strong air-fuel mixture generated in the cylinder 16 collapses and becomes turbulent in the latter half of the compression stroke of the engine, so that the flow of the air-fuel mixture in the combustion chamber 5 is strengthened. Ignition of the spark plug 9 in this highly fluid mixture results in stable and rapid combustion, which improves thermal efficiency, significantly improves fuel efficiency, and improves emissions.

Further, in the high load region of the engine, the tumble control valve 13 is in a state where both the first passage 10d and the second passage 10e of the intake passage 10a are opened by the drive control of an engine control unit (not shown). Therefore, during the intake stroke of the engine with the intake valve 4 opened, a large amount of intake air flowing from the intake manifold 12 into the intake passage 10a of the injector holder 10 becomes a deflected flow via the first passage 10d and the second passage 10e. Without flowing into the intake port 6. Then, the fuel injected from the injector 11 is mixed into the intake air in the intake port 6, so that a uniform air-fuel mixture is sucked into the cylinder 16, and in the combustion chamber 5 in the latter stage of the compression stroke, By igniting the ignition plug 9, good uniform combustion with high filling efficiency is performed and high output is obtained.

From the viewpoint of manufacturing the engine air intake system according to the present embodiment, the injector holder 10 in which the tumbling control valve 13 is pre-assembled is simply installed between the cylinder head 3 and the intake manifold 12. Since it is good, the assembly work is simple, and it can be easily applied to an existing engine by only changing the injector holder 10.

Further, since the downstream end 14 a of the partition plate 14 formed integrally with the injector holder 10 is set in the same plane position as the joint surface 10 f of the injector holder 10 to the cylinder head 3, the injector holder 10 is provided. The joining surface 10f is easily processed, and the work of connecting the injector holder 10 to the cylinder head 3 is also easy.

In this embodiment, the partition plate 14 is integrally formed with the injector holder 10 by the aluminum die casting method, but the partition plate 14 is manufactured as a separate member and press-fitted into the intake passage 10 a of the injector holder 10. You may do it.

Further, the downstream end of the partition plate 14 does not have to be set in the same plane position as the joint surface 10 f of the injector holder 10 to the cylinder head 3. For example, as shown in FIGS. 2 (a) and 2 (b), the downstream end 14 a of the partition plate 14 is projected into the inlet of the intake port 6 within a range where the fuel injected from the injector 11 does not directly hit. By doing so, the deflected flow in the intake port 6 can be made even stronger. In addition, as shown in FIGS. 3 (a) and 3 (b), the downstream end 14a of the partition plate 14 is largely projected into the inlet of the intake port 6, and the portion where the fuel injected from the injector 11 hits is cut. The notch 14b may be provided, and in this case, a stronger deflection flow can be generated in the intake port 6.

[0025]

[Effect of device]

 As described above, according to the present invention, the operation of the tumble control valve causes a deflected flow for generating a tumble flow in the intake passage of the injector holder, and this deflected flow is maintained as it is by the partition wall and is maintained in the intake port. Guided to the entrance. Therefore, a strong deflection flow flows as a deflection flow for generating the tumble flow in the intake port, and a strong tumble flow can be generated in the cylinder.

Since the tumble control valve is provided in the intake passage in the injector holder that is continuous with the intake port, the distance between the tumble control valve and the intake port inlet is short, and the deflection flow for generating the tumble flow is It can be prevented from being carelessly weakened.

Further, from a manufacturing point of view, since it is sufficient to assemble the injector holder provided with the tumble control valve and the partition plate between the cylinder head and the intake manifold, the assembling work is simple and the existing It can be easily applied to the engine by only changing the injector holder.

[Brief description of drawings]

FIG. 1 shows an embodiment of an engine air intake device according to the present invention, (a) is a vertical sectional view showing the overall schematic configuration and action, and (b) is a front view of a tumble control valve in one embodiment. .

FIG. 2 shows a modification of the partition plate in one embodiment,
(A) is the side view, (b) is the front view.

FIG. 3 shows another modification of the partition plate in one embodiment,
(A) is the side view, (b) is the front view.

[Explanation of symbols]

 1 Engine Main Body 2 Cylinder Block 3 Cylinder Head 4 Intake Valve 5 Combustion Chamber 6 Intake Port 7 Exhaust Valve 8 Exhaust Port 9 Spark Plug 10 Injector Holder 10a Intake Passage 10b Attachment Part 10c Wall Side One Side 10d First Passage 10e Second Passage 10f Joining Surface 11 Injector 12 Intake manifold 13 Tumble control valve 13a Notch 14 Partition plate 14a Downstream end 14b Notch 15 Piston 16 Cylinder

Claims (4)

[Scope of utility model registration request] 1. An intake system for an engine, comprising: an intake passage connected to an intake port of the engine; and an injector holder having an injector mounting portion for injecting fuel into the intake port and connected to a cylinder head. In the intake passage of the holder, a tumble control valve that generates a deflected flow for generating a tumble flow and a partition wall that maintains the deflected flow generated by this tumble control valve and guides it to the inlet of the intake port are provided. Characteristic engine intake device. 2. The intake system for an engine according to claim 1, wherein the partition wall extends to the inside of the inlet of the intake port. 3. The tumble control valve is provided on the upstream side of the partition wall.
Intake device for the engine described. 4. The tumble control valve is a butterfly valve having a cutout portion on one side of an intake passage divided into two by the partition wall. Intake device for the engine described.