JPS6213727A - Internal-combustion engine - Google Patents

Abstract

PURPOSE:To improve combustion efficiency as well as to reduce black smoke so sharply, by installing a precombustion chamber, provided with a device being interconnected to a main combustion chamber and performing its compression, and a heating device heating and vaporizing the fuel spouted out of a fuel feeding device. CONSTITUTION:A pressure ignition engine 1 is interconnected to a main combustion chamber 4 and provided with a precombustion chamber 7 having an auxiliary piston which performs compression at the specified ignition timing. Also, there is provided with a heater 26 which heats and vaporizes the fuel spouted out of a fuel feeding device 25. Pressure ignition is carried out inside the precombustion chamber 7 whereby a combustion air-fuel mixture is furiously spouted from the precombustion chamber 7 to the main combustion chamber 4 and combustion takes place at the main combustion chamber 4. Thus, combustion efficiency is made so better and black smoke contained in exhaust gas is sharply reducible.

Description

[Detailed description of the invention] a. Industrial application field The present invention relates to an improved internal combustion engine.

b. Prior Art Combustion methods for internal combustion engines, such as compression ignition engines, include direct injection, pre-combustion chamber, swirl chamber, and air chamber.

However, in both combustion methods, liquid fuel is injected directly into the combustion chamber, so before the injected liquid fuel sufficiently vaporizes and forms a homogeneous gas mixture with air. In some cases, compression ignition combustion was initiated.

In this case, combustion efficiency decreases, unburned hydrocarbons are generated in the combustion chamber, and black smoke is emitted from the compression ignition engine, contributing to air pollution.

The present invention was invented in view of the above-mentioned circumstances, and its purpose is to provide an internal combustion engine that has good combustion efficiency and can significantly reduce black smoke contained in exhaust gas. be.

Means for Solving Problem C2 In order to achieve the above object, the present invention provides a pre-combustion chamber that communicates with the main combustion chamber and is provided with means for performing compression at a predetermined ignition timing, and a liquid inside the pre-combustion chamber. The device includes a fuel supply means that injects and supplies fuel, and a heating means that heats and vaporizes the fuel, and vaporizes and compresses and ignites the liquid fuel supplied into the precombustion chamber, thereby causing the combustion mixture to flow from the precombustion chamber. The fuel is violently ejected and sent to the main combustion chamber 4 to ensure sufficient combustion within the main combustion chamber 4. -d. Examples Hereinafter, examples of the internal combustion engine according to the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIGS. 1 and 2, the pressure ignition engine 1 includes a main combustion chamber 4 formed by a cylinder 2 and a piston 3, and an auxiliary cylinder 5 and an auxiliary piston 6.
It consists of a pre-combustion chamber 7 formed by a combustion chamber 7, and an auxiliary chamber 8 located between the pre-combustion chamber 7 and the main combustion chamber 4.

The pre-combustion chamber 7 and the sub-chamber 8 communicate with each other via a passage 9 formed in the side wall of the auxiliary cylinder 5, and the sub-chamber 8 and the main combustion chamber 4 communicate with each other via an ejection passage 1) formed in the cylinder head block 10. are communicated with each other. .

Further, the pre-combustion chamber 7 and the sub-chamber 8 are communicated with each other via a passage 13 having a check valve 12.

Note that the subchamber 8 is formed to have a substantially circular cross-sectional shape so that a swirl can be efficiently formed inside the subchamber 8.

The auxiliary piston 6 moves up and down within the auxiliary cylinder 5 following a cam 14 disposed on its head, and in particular, in order to make its timing correspond to the up and down movement of the main piston 3, the crankshaft 15 and the camshaft A coil spring 19 is installed between the spring receiver F and the spring receiver 1 arranged above the auxiliary piston. It has a structure that urges the auxiliary piston 6 upward.

Passage 9 connects its population 20 to the upper part of antechamber 8 and its exit 2
1 is located in the upper part of the pre-combustion chamber 7, and the ejection passage 1) is located in the lower part of the pre-combustion chamber 7, and is provided obliquely to facilitate the formation of swirl in the sub-chamber 8.

The check valve 12 has its valve body 23 connected to the auxiliary cylinder 5 by a spring 22 disposed between the relief valve and the auxiliary cylinder 5.
The passage 13 is normally closed by contacting the side valve seat 24, and the passage 13 is opened only when the pressure in the pre-combustion chamber 7 becomes extremely large compared to the pressure in the sub-chamber 3. It is something to do.

Furthermore, a fuel supply means 25 is installed on the side wall of the auxiliary cylinder 5 to inject and supply liquid fuel into the precombustion chamber 7 .

Further, in the pre-combustion chamber 7, there is a heater 2 such as a glow plug that heats the liquid fuel ejected from the fuel supply means 25.
6 is installed. The heater 26 is the fuel supply means 2
It is preferable to locate the fuel injection port 25a on an extension line of the fuel injection port 25a.

Next, we will explain the operation of this compression ignition engine l in Figures 2 (1) to (T
This will be explained with reference to V).

FIG. 2(1) shows the start of compression of the air taken into the main combustion chamber 4. FIG. 2(n) shows the compression process, in which the auxiliary piston 6 is still located at the top of the auxiliary cylinder 5.

At this time, the compressed air in the main combustion chamber 4 flows into the subchamber 8 through the passage 1) to form a swirl 8a within the subchamber, and then flows into the precombustion chamber 7 via the passage 9. The flow will be carried out sequentially.

The injection timing of the liquid fuel into the pre-combustion chamber 7 is set in the period from the bottom dead center of the piston to the 106th crank angle after passing through the top dead center in the compression process of step 3.

During this time, the liquid fuel ejected from the fuel supply means 25 is
It collides with the heater 26, is heated by the heater, and is vaporized. The heated fuel encounters the compressed air flowing into the pre-combustion chamber 7, is activated and diffuses, and its vaporization is further promoted.

On the other hand, the timing at which the auxiliary piston 6 starts operating is set between the bottom dead center and the top dead center in the compression process of the piston 2, and this may be varied depending on the engine speed, or may be set in advance. , to be determined accordingly.

Further, the timing at which the operation of the auxiliary piston 6 ends is set at a crank angle of 30 degrees after the top dead center during the expansion stroke of the piston 2.

As mentioned above, when the piston 3 enters the compression process, the auxiliary piston 6 also begins to descend in conjunction with this, closes the outlet 21 of the passage 9, and continues to descend, thereby reducing the air-fuel mixture in the pre-combustion chamber 7. is compressed to at least the pressure in the main combustion chamber 4 (see FIG. 2 (TV)).

In this way, when the auxiliary piston 6 is positioned near the lowest part of the auxiliary cylinder 5, the compressed air-fuel mixture is ignited, and its explosive force opens the check valve 12, causing combustion gas to be ejected into the auxiliary chamber 8.

Swirl combustion occurs in the pre-chamber 8, which further increases the momentum of the combustion, which becomes a jet and flows into the passage 1).
The air is violently injected into the main combustion chamber 4 through the main combustion chamber, and complete combustion occurs within the main combustion chamber by mixing with fresh air.

FIG. 2 (TV) shows the state at the end of the compression stroke in the piston 2, and after this, the auxiliary piston 6
is located at the lowest part of the auxiliary cylinder 5 until air begins to be sucked into the main combustion chamber 4 again.

Combustion within the main combustion chamber 4 continues from the compression process to the expansion process, and ends midway through this process.

FIG. 3 shows a case in which a through hole 27 is formed in the valve body 23 of the check valve 12 in place of the passage 9 formed in the auxiliary cylinder 5, and the pre-combustion chamber 7 and the sub-chamber 8 communicate with each other through the through hole 27. be done.

This hole 27 is easier to form than the passage 9, and the length of the communication passage between the pre-chamber 8 and the pre-combustion chamber 7 can be shortened. This allows the compressed air to flow in quickly, allowing the engine to operate at even higher speeds.

It is also possible to rotate the valve body 23 having the hole 27 by a cam mechanism (not shown) or the like, thereby establishing communication between the auxiliary chamber 8 and the pre-combustion chamber 7 only at predetermined times. The rotational drive of the valve body 23 can also be linked to the downward movement of the auxiliary piston 6.

In the above embodiment, fuel is supplied only into the pre-combustion chamber 7, but it is also possible to supply liquid fuel or air-fuel mixture to either or both of the sub-chamber 8 and the main combustion chamber 4. You can also do it.

2, indicated by a dotted line in FIG. 1, is a fuel supply means for injecting liquid fuel into the auxiliary chamber 8.

In addition, if fuel is supplied to the main combustion chamber 4 in addition to the pre-chamber 8 at the same time, light oil or kerosene is supplied to the pre-combustion chamber, and a carburetor brake, for example, is used between the pre-combustion chamber 8 and the main combustion chamber 4. It is possible to supply a lean mixture of alcohol or gasoline formed by

In this embodiment, the pre-chamber 8 is provided to constitute a compression ignition engine, but in the present invention, the pre-chamber is omitted,
The pre-combustion chamber may communicate directly with the main combustion chamber.

Furthermore, the present invention is applicable not only to compression ignition engines but also to gasoline engines that employ a normal autocycle.

As described in detail of the e0 invention, according to the internal combustion engine according to the present invention, compression ignition is performed in a relatively small-capacity precombustion chamber, so ignition performance is good, and after the ignition, main combustion is carried out from the precombustion chamber. Since the combustion mixture is violently injected into the interior of the main combustion chamber and completely combusted within the main combustion chamber, the combustion occurs smoothly and completely.Therefore, hydrocarbon emissions are small and NOx emissions are reduced. It is extremely effective in suppressing toxic exhaust gases.

[Brief explanation of drawings]

FIG. 1 is a sectional view of essential parts showing one embodiment of an internal combustion engine according to the present invention, FIGS. 2(I) to (IV) are sectional views conceptually shown to explain the compression combustion process, FIG. 3 is a sectional view showing another example of the valve body of the check valve in the embodiment shown in FIG. 1... Compression ignition engine, 4... Main combustion chamber, 7...
... Pre-combustion chamber, 8... Sub-chamber, 9, 1).
13... Passage, 12... Check valve, 14...
Cam, 23... Valve body, 25, 28...
- Fuel supply means, 26... heater, 27... hole. M 1 Figure 3 jIIZ Figure

Claims (7)

[Claims] (1) A pre-combustion chamber that communicates with the main combustion chamber and is equipped with means for performing compression at a predetermined ignition timing, a fuel supply means for injecting and supplying liquid fuel into the pre-combustion chamber, and liquid fuel injected from the fuel supply means. and a heating means for heating and vaporizing the fuel, and compressing and igniting the fuel in the pre-combustion chamber, thereby violently injecting the combustion mixture from the pre-combustion chamber to the main combustion chamber to cause combustion in the main combustion chamber. An internal combustion engine characterized by: (2) Claim No. (2) characterized in that an auxiliary chamber is provided between the main combustion chamber and the pre-combustion chamber and communicate with each other.
The internal combustion engine described in item 1). (3) The internal combustion engine according to claim (2), wherein the subchamber has a substantially circular cross-sectional shape that facilitates the formation of swirl. (4) The internal combustion engine according to claim (2) or (3), further comprising a fuel supply means for supplying liquid fuel or an air-fuel mixture into the auxiliary chamber. (5) The internal combustion engine according to claim 2 or 3, further comprising a fuel supply means for supplying liquid fuel or an air-fuel mixture to the auxiliary chamber and the main combustion chamber. institution. (6) The internal combustion engine according to claim (2) or (3), characterized in that a check valve is provided between the subchamber and the pre-combustion chamber. (7) Claims (2) or (3) characterized in that a through hole is formed in the valve body of the check valve to communicate between the sub-chamber and the pre-combustion chamber. Internal combustion engine as described.