JPS62195409A - Hot metal inserted in inner wall of auxiliary chamber of auxiliary chamber type diesel engine - Google Patents

Abstract

PURPOSE:To improve anti-knock property of an engine by making an insertion hot metal installed in an upper pre-combustion chamber with a material of high heat resistance and great heat capacity. CONSTITUTION:A pre-combustion chamber is divided into an upper chamber 3 and a lower chamber 4 with a bowl-shaped inner wall insertion hot metal 1 installed in the upper chamber 3. An injection nozzle 2 has a pre-injection hole 6. The lower chamber 4 is provided with a main injection port 5. Since the upper chamber 3 is made of a heat-resistant alloy with high heat insulation property and the inner wall insertion hot metal 1 is of good heat conductivity, the inner wall insertion hot metal 1 reaches a high temperature as the operation goes on to atomize fuel injected from the pre-injection port 5 so that the atomized fuel collides against or approaches the high temperature inner wall insertion hot metal 1 to be burned. Thus, delay in ignition is shortened to improve anti- knock property.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial Application Field The present invention is applicable to pre-chamber type diesel engines, that is, pre-combustion chamber type and swirl chamber type diesel engines, without substantially changing the air flow condition in the pre-chamber. This invention relates to a sintered metal inserted into the sub-chamber wall that improves the knock resistance of an engine when used in combination with a nozzle with vertical injection holes.

(b) It is known that the conventional technology-advanced nozzle with injection holes is effective in improving the knock resistance of diesel engines, but this can be used in combination with the above-mentioned pre-chamber wall insertion annealing to improve the knock resistance. Nothing has been done to further improve this. In addition, since conventional pre-chamber firing metals are not inserted into the inner wall, the air flow conditions within the pre-chamber change due to the firing, and extensive design changes are required and easy to implement in conventional pre-chamber type diesel engines. Not.

(c) Problems to be Solved by the Invention This invention improves the knock resistance of the nozzle with a pre-injection hole without substantially changing the air flow condition in the pre-chamber, and improves the knock resistance of the conventional pre-chamber type diesel engine. The purpose is to obtain a sintered metal for inserting into the sub-chamber wall which can be easily implemented.

(d) Means for Solving the Problems An embodiment in which the present invention is applied to a pre-combustion chamber type diesel engine will be described below with reference to the drawings.

FIG. 1 is a sectional view of the pre-combustion chamber, which is divided into an upper chamber 3 and a lower chamber 4, and a bowl-shaped inner wall inserting metal 1 is attached to the upper chamber 3. The injection nozzle 2 has a pilot injection hole 6 . Lower chamber 4
There is a main nozzle 5.

(E) Functionally, the chamber 3 is made of a heat-resistant alloy and has high heat insulation properties, and the inner wall inserted sintered metal 1 has good thermal conductivity, so the inner wall inserted sintered metal 1 becomes high temperature during operation, and the main injection hole The fuel injected in the opposite direction to the flow direction of the incoming air from 5 becomes fine particles and collides with or approaches the high-temperature inner wall inserted firing metal 1 and burns, so the ignition delay is shortened and the knock resistance is improved. improves. The higher the thermal conductivity and heat capacity, the greater the improvement in knock resistance by the inner wall inserted fired metal 1.

Furthermore, since the inner wall insertion firing metal 1 does not change the inner wall surface shape of the upper chamber 3, the air flow within the sub-chamber does not substantially change.

(F) Effects of the Invention As described above, the present invention improves the knock resistance of a nozzle with a pre-injection hole in a pre-chamber diesel engine. In particular, the improvement in knock resistance during idling operation is remarkable. Moreover, since the air flow condition in the pre-chamber is not substantially changed, it is easy to implement the pre-chamber of a conventional pre-chamber type diesel engine without making any major changes to the pre-chamber.

[Brief explanation of drawings]

FIG. 1 is a sectional view of the pre-combustion chamber. 1... Burning metal inserted into the sub-interior wall 2...Injection nozzle 3...Pre-combustion chamber upper chamber 4...Pre-combustion chamber lower chamber 5...Main spout 6...Prior injection hole

Claims (1)

[Claims] Made of silicon carbide, silicon nitride, etc., or made of molybdenum, etc., and then chemical vapor deposited with alumina, or chemical vapor deposited with silicon, and then heat treated to form a silica film, etc. to form an oxidation-preventing film. , A metal insert for the pre-chamber wall of a pre-chamber diesel engine made of a material with high heat resistance and relatively large thermal conductivity and heat capacity.