JPS597765A - Fuel injection-type internal-combustion engine - Google Patents

Abstract

PURPOSE:To improve the gasification of fuel, combustion, and a fuel consumption rate by jointly utilizing part of a suction port bottom wall and a combustion chamber top wall and by providing an injection valve injecting fuel toward the jointly used wall. CONSTITUTION:The fuel injected and fed from an injection valve 11 hits a jointly used wall 10 and is spattered in a suction port 5, and is concurrently stuck to the jointly used wall 10 in a liquid drip shape. However, the jointly used wall 10 is sufficiently heated by receiving the combustion heat in a combustion chamber 9, thus the fuel drip going to stick to the surface of the joitly used wall 10 is instantly gasified, and the intake air introduced into the suction port 5 is also heated to gasify the atomized fuel. Thereby, the fully gasified fuel is uniformly distributed in the intake air and is introduced into the combustion chamber 9 through an intake valve 7.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fuel-injected internal combustion engine, and more particularly to improving the vaporization characteristics of injected fuel based on improvements in the arrangement position of the intake valve and the shape of the intake boat of the internal combustion engine.

A fuel-injected internal combustion engine injects fuel into an intake boat through a fuel injection valve, draws it as a premixed mixture with intake air into a combustion chamber through the intake valve, and ignites it there.
The so-called electronically controlled fuel injection valve, which electronically controls the fuel injection valve according to engine operating conditions to obtain an optimal fuel supply amount, has come into widespread use due to improvements. (For example, see [Automotive Engineering Zensho Vol. 4, published by Sankaido, July 20, 1980, pages 2-3.) In an internal combustion engine that injects fuel into the intake boat in this way, the intake boat is cooled by the intake air. Because of this, the fuel vaporization characteristics are poor and the injected fuel may adhere to the inner wall of the intake boat, forming a wall flow and being supplied into the combustion chamber.
As a result, the air utilization rate of the fuel deteriorates in the combustion chamber, causing incomplete combustion, resulting in unburned fuel being discharged to the outside as is, and incomplete combustion components and carbon being contained in the exhaust gas. At the same time, there arises the disadvantage that fuel consumption increases.

In view of the disadvantages of the conventional fuel-injected internal combustion engine, the present invention arranges the intake valve so that the center of the intake valve is located on the side farther from the intake manifold mounting surface to the cylinder head with respect to the cylinder center line. The bottom wall of the obtained intake boat and the top wall of the combustion chamber are partially shared, and the shared wall is heated by the combustion heat in the combustion chamber, and fuel is injected and supplied from the injection valve toward the heated shared wall. To provide a fuel injection type internal combustion engine which promotes the vaporization of fuel adhering to a common wall and simultaneously heats the interior of the intake boat near the common wall, thereby improving vaporization characteristics. It is.

In the following, four embodiments of the present invention will be described with reference to the drawings, in which an intake manifold 3 and an exhaust manifold 4 are attached to the mounting surface 2. An intake boat 5 connected to an intake manifold 3 and an exhaust boat 6 connected to an exhaust manifold 4 are formed inside the cylinder head 1.The intake boat 5 is connected to the intake valve 7, and the exhaust boat 6 is The exhaust valves 8 communicate with the combustion chambers 9, respectively. The center C of the intake valve 7 is located on the intake manifold 3 with respect to the center line O of the cylinder.
The center d of the exhaust valve 8 is located on the side closer to the mounting surface 2 with respect to the cylinder center line 0.

Therefore, the intake boat passes above the top of the combustion chamber 9 in the process of being connected to the intake valve 7 from its inlet. As a result, the top wall of the combustion chamber 9 and the bottom wall of the intake boat 5 are partially shared by the common wall 10.

The common wall 10 receives the combustion heat in the combustion chamber 9 and is sufficiently heated.

Then, the fuel injection direction of the injection valve 11 attached to the intake manifold 3 is directed toward the upper surface of the common wall 10. F in the diagram
is the fuel spray injected and supplied from the injection valve 11.

According to this configuration, the fuel injected from the injection valve 11 hits the common wall 10 and scatters into the intake boat 5, and at the same time, it also adheres to the common wall 10 in the form of droplets. However, since the common wall 10 is sufficiently heated by the combustion heat in the combustion chamber 9, the fuel droplets that try to adhere to the top surface of the common wall 10 are instantly vaporized and guided into the intake boat 5. The intake air is also heated to vaporize the fuel droplets. As a result, sufficiently vaporized fuel is uniformly distributed in the intake air and introduced into the combustion chamber 9 via the intake valve 7. Therefore, if the air-fuel mixture is ignited by a spark plug (not shown), a good combustion state will be achieved with good ignitability and a high flame propagation speed.

Therefore, there is no droplet-like or wall-like fuel flow flowing along the intake boat 5, and due to the smooth combustion state, it is possible to reduce the amount of unburned fuel layer adhering to the inner wall surface of the combustion chamber. Unburnt fuel in the combustion gas discharged from the rice supply, C
Fuel economy is improved because incomplete combustion components such as 09HC and harmful components such as carbon are reduced, and output can be extracted by effectively utilizing fuel.

If fins 13 are formed on the top surface of the common wall 10 to extend in the intake air flow direction, the heat transfer effect of the common wall 10 to the fuel and the intake air will be further enhanced, and the vaporization characteristics will be further improved.

In addition, since the intake valve 7 can be disposed at a sufficiently far distance from the intake manifold mounting surface 2, the shape of the intake boat 5 can be curved so that its outlet portion faces tangentially to the inner circumferential wall of the combustion chamber 9. It is possible to easily enhance the swirl of the air-fuel mixture sucked into the combustion chamber 9.

The embodiment shown in Fig. 1 is a counter 70-type in which the exhaust boat and the intake boat are on the same side, but in this type of internal combustion engine, the intake manifold mounting surface is located on the same side as shown in Fig. 2. An injection valve 11a can be arranged on the cylinder head wall opposite to 2. This has the advantage that it is extremely easy to secure the installation space for the injection valve, which is a problem when the intake manifold mounting surface and the exhaust manifold mounting surface are arranged on the same surface in a sycamore turbulent internal combustion engine.

In the present invention, the combustion heat in the combustion chamber 9 superheats the shared wall 10 between the intake boat 5 and the vaporization characteristics of the fuel spray injected and supplied thereto. If there is a risk of overheating the common wall 10, increasing the intake air temperature and lowering the charging efficiency, resulting in a decrease in output, one or more engine cooling water passages 21 are provided in the common wall 10, and It is also possible to heat the fuel adhering to the common wall 10 and the floating fuel in the vicinity to an appropriate temperature and vaporize it via the cooling water. (See Figures 3 (4) and (B) 9) As described above, according to the present invention, the intake valve is disposed on the side far from the intake manifold mounting surface of the cylinder head with respect to the center line of the cylinder head, and is connected to the bottom wall of the intake boat. Since the top wall of the combustion chamber is partially co-coordinated with an injector that injects fuel toward the common wall, fuel vaporization is improved, combustion is improved, fuel consumption rate is increased, and harmonics in the exhaust gas are reduced. Component-containing groups are reduced.

[Brief explanation of drawings]

FIG. 1 shows one embodiment of the present invention, (A) is a cross-sectional plan view, (B) is a sectional view taken along the line I-I in (A), and FIG. 2 shows another embodiment of the present invention. The cross-sectional plan view, FIG. 3, is the third embodiment of the present invention.
FIG. 3A is a vertical cross-sectional view, and FIG. 3B is a cross-sectional plan view of the cylinder head. 1... Cylinder head 2... Intake manifold mounting surface 3... Intake manifold 5... Intake boat 7... Intake valve 9... Combustion chamber 10... Common wall 11.11a... Injection valve C...Intake valve center 0...Cylinder center line Patent applicant Fujio Sasashima, Patent attorney representing Nissan Motor Co., Ltd.

Claims (1)

[Claims] With respect to the cylinder centerline, the center of the intake valve is located on the side far from the intake manifold mounting surface of the cylinder head, so that the bottom wall of the intake boat and the top wall of the combustion chamber share a part, and fuel is injected toward the common wall. A fuel-injected internal combustion engine characterized by being equipped with an injection valve.