JPH03294620A - Diesel engine swirl combustion chamber - Google Patents

Abstract

PURPOSE:To spread width of vortex flow and perform perfect combustion by providing a vortex width spreading means on the vortex flow passing route on the inner wall of a vortex chamber, and constituting the vortex flow width spreading mans out of recessed and projection channels of multiple spiral. CONSTITUTION:A vortex flow width spreading mean 5 is provided on the vortex flow 4 passing route on the inner wall of a vortex chamber 3. The vortex flow width spreading means 5 is constituted out of recessed and projecting channels 7 of multiple spiral having the swirling center 6 near by the center in the width direction of vortex flow 4. Outside half part 8 of the vortex flow 4 is guided with the recessed and projecting channels 7 spreading width from the lower stream side to the swirling center 6, while spreading its width in order. Inside half part 9 of the vortex flow 4 is guided with the recessed and projecting channels 7, while narrowing width once and spreading width in order by mutual inner collision. In this way, the width of vortex flow can be spread and perfect combustion of fuel can be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a swirl combustion chamber for a diesel engine.

[Basic Structure] The basic structure of the swirl chamber type combustion chamber of a diesel engine, which is the premise of the present invention, is as follows.

For example, as shown in Fig. 1, a main combustion chamber 1 of a diesel engine is communicated with a whirlpool chamber 3 through a nozzle 2, and in the compression process, compressed air compressed in the main combustion chamber 1 is transferred from the nozzle 2 to the whirlpool chamber 3. It is configured to be press-fitted to generate a vortex flow 4 within the vortex chamber 3.

[Prior Art] In the above-mentioned basic structure, the vortex chamber conventionally has an inner wall surface formed with a smooth curved surface, and guides the compressed air flow flowing in from the nozzle only in the flow direction to create a thin flow. It is configured so that it occurs.

[Invention or problem to be solved] However, the prior art described in -J- has the following problem.

In other words, the thin flow generated by guiding the narrow compressed air flow flowing in from the nozzle only in the flow direction is narrow and only swirls within the narrow width of the thin chamber, so it is difficult to absorb fuel. Difficult to disperse throughout the room.

For this reason, during startup or high-load operation where a large amount of fuel is injected, partially high concentration fuel tends to cause incomplete combustion due to lack of air, resulting in no increase in output and a large amount of smoke. However, it also causes problems such as high fuel consumption and high costs.

An object of the present invention is to make it possible to expand the width of the thin flow.

[Means for Solving the Problems] The present invention is characterized in that the swirl chamber 3 in the basic structure is configured as follows.

For example, as shown in FIG.
A eddy flow expansion means 5 is provided on the passage path, and this eddy flow width expansion means 5 has a turning center 6 near the center in the width direction of the thin flow 4.
It is composed of multiple concave and convex grooves 7 having a multiple spiral shape.

The uneven strips 7 are formed on a part of the inner circumferential surface of the whirl chamber 3, such as the lower half as shown in FIG. 1, the lower half, the horizontal half, etc. as shown in FIG. , may be formed over the entire surface as shown in FIG.

Further, the uneven strips 7 may be formed concentrically as shown in FIG. 1 or 2, or may be formed spirally as shown in FIG. 3.

When the uneven strips 7 are formed in a spiral shape, the directions of rotation may be reversed in the upper and lower halves of the inner wall surface of the swirl chamber 3, as shown in FIG. 3, or they may be the same. Good too.

[Effect] The invention works as follows.

For example, as shown in FIG. 1(B), as can be seen from the locus of arbitrary points X1 and The width is gradually expanded while being guided by the concave and convex strips 7 that gradually widen from the side toward the turning center 6.

In addition, the inner half 9 of the eddy flow 4 can be located at any point Y1 or Y
As can be seen from the locus 2, the vicinity of the center of rotation 6 of the uneven strip 7 is drawn to the inner circumferential surface of the vortex chamber 3 as the width of the outer half 8 of the eddy flow 4 expands, and the flow path is separated from the center of rotation 6. The width is once narrowed while being guided by the concave and convex strips 7 whose width gradually becomes narrower toward the upper side, and then the width is gradually expanded by mutual internal collision.

[effect] The present invention has the following effects.

That is, since the width of the eddy flow can be expanded by the multiple swirl-like irregularities, the thin flow can be swirled over a wide width of the thin chamber, and the fuel can be dispersed well.

As a result, complete combustion of fuel can be achieved even during startup or high-load operation, when the amount of fuel injected is large, resulting in an increase in output compared to conventional models that could only generate narrow swirls. In addition, the amount of smoke generated can be reduced, and fuel consumption can be reduced.

[Example] Embodiments of the present invention will be described based on the drawings.

First, a first embodiment shown in FIG. 1 will be described.

In FIG. 1, reference numeral 10 indicates a spiral combustion chamber of a diesel engine.

This whirlpool combustion chamber 10 is constructed by assembling a shilling head 12 on the top of a cylindrical block 11.
A piston head 14 is fitted into the cylinder chamber 13 of the cylinder head 1, a main combustion chamber l is formed between the piston head 14 and the cylinder head 12, a whirlpool chamber 3 is formed within the wall of the cylinder head 12, and a whirlpool chamber A fuel injection nozzle 15 and a glow plug 16 are placed inside the main combustion chamber 1, and the swirl chamber 3 is communicated with the main combustion chamber 1 through the nozzle 2. It is configured to be press-fitted into the vortex chamber 3 to generate a vortex flow within the vortex chamber 3.

This swirl chamber type combustion chamber 10 is provided with swirl flow width expanding means 5 for expanding the width of the swirl flow 4.

The vortex flow width expanding means 5 is constructed by running concentric grooves 7 on the upper half of the inner circumferential surface of the vortex chamber 3, with the top of the vortex being the center of rotation 6.

Further, in this swirl chamber type combustion chamber 10, an annular cooling water passage 18 is provided at two locations above and below the nozzle nozzle nozzle nozzle 17 in order to prevent the nozzle nozzle nozzle nozzle 17 from overheating.

The cooling water passage 18 is constituted by a groove recessed in the inner circumferential surface of the mouthpiece fitting hole 19 of the 7-liner nozzle 12, and communicates with the cooling water socket 20 for water cooling around the swirl chamber 3 through a plurality of communication passages 21.

In the second embodiment shown in FIG. 2, the uneven strip 7 is formed on the upper half of the inner wall surface of the thin chamber 3 in the first embodiment shown in FIG. A plurality of heat radiation rods 22 (made of a material with good thermal conductivity such as copper) are formed in the lower half of the water cooling head jacket 20 and are in contact with the nozzle mouthpiece 17 instead of the annular cooling water passage 18. It is made to protrude inward.

In the third embodiment shown in FIG. 3, in place of the first embodiment shown in FIG. 1 in which the concave and convex strips 7 are concentrically formed only on the second part of the inner wall surface of the thin chamber 3, they are formed in a spiral shape. It is formed over the entire inner wall surface of the whirlpool chamber 3, and the direction of rotation is opposite in the upper and lower halves.

[Brief explanation of drawings]

1 to 3 are diagrams for explaining a swirl chamber type combustion chamber of a diesel engine according to an embodiment of the present invention, and FIG. 1(A) is a longitudinal sectional view of the first embodiment, and FIG. ) is a sectional view taken along the line B-B in Figure 1 (A), and Figure 1 (C) is a cross-sectional view taken along the line C-C in Figure 1 (A).
2 is a longitudinal sectional view of the second embodiment, and FIG. 3 is a longitudinal sectional view of the third embodiment. 1. Main combustion chamber, 2. Nozzle port, 3. Whirlpool chamber, 4.
Thin flow, 5... Eddy flow width expansion means, 6... 7 center of rotation, 7... Uneven strip.

Claims (1)

[Claims] 1. The main combustion chamber 1 of the diesel engine is communicated with the whirlpool chamber 3 through the nozzle 2, and in the compression process, the compressed air compressed in the main combustion chamber 1 is forced into the whirlpool chamber 3 through the nozzle 2. In the whirlpool type combustion chamber of a diesel engine configured to generate a whirlpool flow 4 in the whirlpool chamber 3, a whirlpool flow width expanding means 5 is provided on the passage of the whirlpool flow 4 on the inner wall surface of the whirlpool chamber 3, A swirl chamber type combustion chamber for a diesel engine, characterized in that the swirl flow width expanding means 5 is constituted by a multi-swirling uneven strip 7 having a swirl center 6 near the center in the width direction of the swirl flow 4.