JPS6316833Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of a diesel engine equipped with a swirl sub-combustion chamber (hereinafter simply referred to as a swirl chamber).

Conventionally, diesel engines with a vortex chamber have a glow plug installed in the vortex chamber for use in cold weather, but since the heater part of this plug is placed to protrude into the vortex chamber, it has the effect of accelerating starting in cold weather. On the other hand, it has the disadvantage that it obstructs the generation of vortex flow in the vortex chamber and the propagation of flame when the temperature is not cold. In order to improve this problem, as shown in Figs. 3 and 4, a cap (lower chamber) 6 is attached to the cylinder head 4.
A diesel engine with a vortex chamber is known in which a vortex chamber 30 is formed by inserting a vortex chamber 30 and a ring-shaped heater 40 is provided at the upper end of a base 60 via a ring-shaped metal gasket 8. A diesel engine with a pre-chamber equipped with a similar heater was published in JP-A-Sho.
It has also been proposed in Publication No. 54-96615 and Publication No. 7382 of 1982.

Since these diesel engines with a pre-chamber do not have glow plugs, the above-mentioned problems can be improved, but a heating element 20) is provided around the entire circumference of the heater 40 to make the entire heater 40 red hot. Since the side 40b of the mouthpiece 60 that is an extension of the communication port 50 and comes into contact with the airflow from the main combustion chamber is cooled by the airflow, compared to other parts of the heater 40. Therefore, the resistance increases and more heat is consumed.

Therefore, as is well known, in a diesel engine with a pre-chamber where the power supply voltage is constant, the side opposite to the side 40b where the air flow comes into contact has the highest amount of heat for atomization and ignition combustion of the injected fuel. Heating element 2 located on the side 40a where the required injected fuel collides
The current supplied to heating element 2 is reduced, and the current supplied to heating element 2 is reduced.
Since the calorific value of zero is reduced, there is a risk that the promotion of atomization and the promotion of ignition of the injected fuel will be impaired.

In addition, N is a fuel injection nozzle, 10 is a heating switch, 11 is a power source, and 90 and 120 are electrode rods.

The present invention solves the problem of the conventional heater in the vortex chamber, that is, the air flow from the main combustion chamber is located on the opposite side of the side where the injected fuel from the fuel injection nozzle collides and is on the extension of the communication port in the lower chamber. A heat generating part is provided on the side that comes into contact, and the heat generating part is cooled by the air flow, increasing resistance and expending a large amount of heat. This was devised to solve the problem of the supply current being reduced and the amount of heat generated in the heat generating part being reduced. A heat generating part is provided only on the side where the injected fuel collides, thereby preventing the supply current to the heat generating part from decreasing, ensuring the amount of heat generated in the heat generating part, promoting atomization of the injected fuel, and igniting the mixture. The purpose is to provide a diesel engine with a vortex chamber that promotes combustion, and its gist is to provide a diesel engine with a vortex chamber that has a communication port to the main combustion chamber and a lower chamber that is placed above it and faces the tip of the fuel injection nozzle. An upper chamber configured to form a vortex chamber, and a heater having a heat generating part only on the side where the fuel injected from the fuel injection nozzle collides is disposed between the lower chamber and the upper chamber. It is a diesel engine with a whirlpool chamber.

An example of this will be described below with reference to the drawings.

Reference numeral 1 denotes a ring-shaped printed heater made of a refractory material with excellent insulation and heat insulation properties, and in which a heating element 2 is embedded by printing.

3 is a communication port 5 that leads to the main combustion chamber at the bottom of the cylinder head 4 of the diesel engine, as shown in Figure 1.
It consists of a lower chamber part 6 having a lower chamber part 6, and an upper chamber part 8 placed above the lower chamber part 6 and configured such that the tip of the fuel injection nozzle N faces therein, and creates a vortex flow in the air flowing in from the main combustion chamber inside. In this vortex chamber, the print heater 1 is placed on the upper surface of the lower chamber part 6 of this vortex chamber 3 via a ring-shaped metal gasket 8 for gas sealing and buffering, and the upper chamber part 6 is placed on the upper surface of the vortex chamber. 7 is placed thereon.

The heater 1 has a heat generating element 2 printed in a rectangular wave shape on the side where the fuel injected from the injection nozzle N collides to form a heat generating part 1a, and one end of the heat generating element 2 is suitably insulated on the outer periphery. It is connected to an electrode rod 9 and connected to a power source 11 via a heating switch 10. Further, the other end of the heating element 2 is connected to a suitable electrode rod 12, and is configured to be grounded via the electrode rod 12.

In addition, a lower chamber part 6 and an upper chamber part 7 forming the vortex chamber 3
is made of ceramic, which is highly heat resistant and heat insulating. Furthermore, the heating switch 10 may also be used as an ordinary key switch,
It may be provided independently.

When starting the diesel engine with a vortex chamber configured as described above in cold weather, when the heating switch 10 is closed, a current is supplied from the power source 11, which is a constant voltage power source, to the heating element of the print heater 1 via the electrode rod 9. 2, the heat generating part 1a provided on the side where the injected fuel collides becomes red hot.

Therefore, since the injected fuel from the fuel injection nozzle N collides with the heat generating part 1a and is heated, the atomization of the injected fuel can be promoted, and the vortex chamber 3 is made of ceramic to provide heat insulation, thereby making it possible to heat the print heater. Since the exothermic effect of No. 1 is improved, a combustible atmosphere is formed on the inner surface, and ignition and combustion of the mixture consisting of the injected fuel and the air flow is extremely promoted.

As described above, the diesel engine with a swirl chamber according to the present invention has a lower chamber section having a communication port to the main combustion chamber, and an upper chamber section placed above the lower chamber section and configured such that the tip of the fuel injection nozzle faces. A heater forming a vortex chamber and provided with a heat generating part only on the side where the fuel injected from the fuel injection nozzle collides is disposed between the lower chamber part and the upper chamber part, so that there is no heat inside the vortex chamber. Cooling of the heat generating part of the heater by the inflowing air flow is avoided, thereby preventing a reduction in the current supplied to the heat generating part and making it possible to generate a sufficient amount of heat.

Therefore, the atomization of the injected fuel is promoted, and the ignition and combustion of the mixture of the injected fuel and the air flow in the vortex chamber is promoted.

Furthermore, by improving the heat generation efficiency of the heater, it is possible to use a heater with lower heat generation performance than the heater in a conventional diesel engine with a pre-chamber.

In addition, in the conventional examples shown in FIGS. 3 and 4, as well as the above-mentioned Japanese Unexamined Patent Publication No. 54-96615 and Japanese Utility Model Publication No. 50-7382, a heating element is arranged all around the heater of a diesel engine with a pre-chamber. In other words, the heat generating part is provided on the side opposite to the side where the injected fuel from the fuel injection nozzle collides, on the extension of the communication port in the lower chamber, and on the side where the air flow from the main combustion chamber comes into contact. As the heat generating part is cooled by the airflow, the resistance increases and a large amount of heat is expended, the current supplied to the heat generating part provided on the side that the injected fuel collides with decreases, and the heat generating part This has the effect of preventing the problem of a reduction in the amount of heat generated.

[Brief explanation of the drawing]

Fig. 1 is an enlarged vertical cross-sectional view of the essential parts of a diesel engine with a swirl chamber according to an embodiment of the present invention, Fig. 2 is a partially cutaway plan view of a printed heater of the same embodiment, and Fig. 3 is a diagram of a conventional diesel engine with a swirl chamber. FIG. 4 is an enlarged vertical cross-sectional view of the main part and a cross-sectional view of the conventional print heater. 1; Print heater, 1a; Heat generating part, 2; Heat generating element, 3; Vortex chamber, 6; Lower chamber part, 7; Upper chamber part, 8;
Metal gasket, 9, 12; electrode rod, 10; heating switch.

Claims (1)

[Scope of utility model registration request] A vortex chamber is formed by a lower chamber having a communication port to the main combustion chamber and an upper chamber placed above the lower chamber and configured such that the tip of the fuel injection nozzle faces, and the injected fuel from the fuel injection nozzle is formed into a vortex chamber. A diesel engine with a vortex chamber, in which a heater having a heat generating part only on the side where it collides is disposed between the lower chamber part and the upper chamber part.