JPS59115428A - Two-cycle internal-combustion engine - Google Patents

Abstract

PURPOSE:To obtain an optimum combustion pressure and as well make it possible to highten the output power of a two-cycle internal-combustion engine, by providing the cylinder head of the engine with a liquefied air injection nozzle, a liquefied air injection cut-off valve and a fuel spraying nozzle including a fuel adjusting valve. CONSTITUTION:There are provided, in the cylinders head 3 of a two-cycle internal-combustion engine, a liquefied air injection nozzle 20 to which liquefied air is fed from a liquefied air supply device 16, a liquefied air injection cut-off valve 19 which is disposed in the liquefied air injection nozzle 20, for opening and closing the nozzle, a fuel spraying nozzle 15 incorporated with a fuel adjusting valve 14 for a cylinder 1 and an exhaust valve 5. Liquefied air is injected into the cylinder 1 in the vicinity of the top dead center of a piston 2, and simultaneously, is mixed with sprayed fuel to be burnt and exploded. The cut-off valve 19 in the liquefied air injection nozzle 20 operates in synchronism with the movement of the piston 2. The fuel adjusting valve 14 opens and closes in synchronism with the piston 2, and as well is adjusted by its opening degree in accordance with engine load.

Description

[Detailed description of the invention] The present invention relates to a two-stroke internal combustion engine.

Conventional internal combustion engines have different combustion methods depending on the fuel used.
Spark ignition combustion is common in gasoline engines, while diesel engines that use less volatile fuels such as light oil and heavy oil use compression ignition combustion, which sprays fuel into high-pressure, high-temperature compressed air and ignites it. The method has been widely adopted.

In this way, conventional internal combustion engines can be broadly classified into spark ignition engines and compression ignition engines.In spark ignition engines, fuel and air are mixed and sucked into the cylinder, where the air is adiabatically compressed, resulting in socking and pre-ignition. There is a risk of this, and there are limits to the ability to improve performance by adopting a high compression ratio due to the octane number of the fuel. Furthermore, in a spark ignition engine, the load is adjusted by throttling the intake air, so the efficiency of the shiatsu diagram inevitably decreases, making it difficult to expect performance improvements.

On the other hand, in conventional compression ignition engines, only air is taken in and compressed, and liquid fuel is injected into the high-pressure air, which has reached a temperature above the fuel's ignition point, and is ignited by spraying, making it impossible to adopt a high compression ratio. It is easy and can improve fuel consumption rate. but.

It is difficult to completely vaporize and burn liquid fuel, and the problem is how to obtain a fine spray of fuel, so fuel injection nozzles have been devised in various ways and have extremely complex structures. ing.

Furthermore, even with these highly improved fuel injection nozzles, ignition delays due to insufficient fineness of fuel atomized particles and power phenomena such as diesel knock that occur as a result cannot be completely eliminated. Therefore, it is difficult to completely vaporize and burn liquid fuel, so in order to operate within the smoke emission limit, it must be used regularly at a large excess air ratio, and there is a restriction that the average effective pressure cannot be increased. This is an obstacle to improving performance.

Conventional internal combustion engines, especially compression ignition engines such as diesel engines, undergo explosive combustion in high-pressure, high-temperature air that is above the ignition point temperature of the fuel, which creates extremely high-pressure, high-temperature pulsations inside the cylinder, causing damage to the piston and cooling mechanism. Due to the durability of the cylinder as a complex structure, the maximum output per cylinder is limited.

The efficiency of internal combustion engines is different from that of ordinary heat engines.

It is more affected by the height of the ultimate pressure than by the temperature during explosive combustion.

This is also why increasing the compression ratio will improve the efficiency of the internal combustion engine, but in conventional internal combustion engines, by increasing the compression ratio.

An increase in the temperature inside the cylinder during combustion is unavoidable.

This was an obstacle to increasing the size and output of internal combustion engines.

The purpose of the present invention is to focus on the above points and provide an internal combustion engine that can obtain an arbitrary compression ratio and that does not reach a relatively high temperature during explosive combustion. a liquid air injection nozzle provided in the liquid air injection nozzle and supplied with liquid air from a liquid air supply device; a liquid air injection opening/closing valve provided in the liquid air injection nozzle to open and close the nozzle;
The cylinder head is provided with a fuel spray nozzle and an exhaust valve each having a fuel control valve attached thereto.

in this case.

(1) The same effect as an extremely high compression ratio can be obtained,
It is easy to improve efficiency.

(2) Therefore, in order to stably increase the compression ratio, there is no need for a conventionally employed supercharger or the like.

(3) Since the temperature reached by explosive combustion is relatively low, the cooling mechanism of the engine can be simplified and the allowable maximum output of a single-cylinder engine can be greatly improved.

Furthermore, the present invention can be applied to internal combustion engines in general.

As will be described later, since not only liquid fuel but also air is injected into the cylinder in a liquid state, the process of compressing air with a single piston is essentially eliminated, resulting in a two-stroke engine.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an explanatory diagram showing a main part of a two-cycle engine according to one embodiment of the present invention in cross section, and FIG. 2 is an explanatory diagram showing a main part of a two-cycle engine according to another embodiment of the present invention in cross section. It is.

In Fig. 1, 1 is a cylinder and 2 is a piston.

3 is the cylinder head, 4 is the frame, and 5 is the exhaust valve.

6 is a piston pin, 7 is a piston pin, 8 is a crank, 9 is a crankshaft, and 10 is a bearing, and these components are exactly the same as a conventional internal combustion engine except that there is no intake valve.

(5) 11 is a fuel tank, 12 is a fuel pump, 13 is a fuel supply pipe, 14 is a fuel control valve, and 15 is a fuel spray nozzle.

On the other hand, 16 is a liquid air supply device, 17 is a liquid air supply pump, 18 is a liquid air supply pipe, 19 is a liquid air injection opening/closing valve, and 20 is a liquid air injection nozzle.

21 is an exhaust pipe.

The fuel system in the internal combustion engine of the present invention is almost the same as the conventional one, but the method of supplying air (or oxygen) is completely different from the conventional one.
Instead of sucking external air into the cylinder 1 and compressing it by the movement of the piston 2 and the opening and closing of the intake valve in synchronization with the movement of the piston 2, in the present invention, liquid air (
Almost infinitely compressed air is injected into the cylinder 1, and at the same time, it mixes with the sprayed fuel, causing combustion and explosion.

The liquid air injection nozzle 20 is equipped with an on-off valve 19.
Operates in synchronization with the movement of piston 2. The fuel control valve 14 not only opens and closes in synchronization with the piston 2 (6), but also adjusts its opening according to the engine load, as in the conventional valve.

When the fuel is highly volatile such as Ll)G or gasoline, the fuel is injected with liquid air (or oxygen) through a separate nozzle, and then atomized in cylinder 1, as shown in Figure 1. Just by mixing, the liquid air will ignite and burn due to its own explosive power, but if the fuel is heavy oil such as C heavy oil, the high temperature gas from the exhaust gas will cause it to burn in the preheater 22, as shown in Figure 2. It is possible to pre-heat the fuel and achieve complete combustion using the suction-mixing spray nozzle 23 that utilizes the supersonic flow velocity generated during liquid air injection.

In this way, in the internal combustion engine according to the present invention, the optimum combustion pressure can be obtained by adjusting the amount of liquid fuel injected, so efficiency can be improved, and the process of compressing air can be omitted, so the engine can be operated in two cycles. It is possible to increase output as an engine. Liquid air has a temperature of about 190° C. below zero, and when it vaporizes, it also takes away the heat of vaporization, so the combustion gas in the cylinder 1 produced by explosive combustion is 500° C. to 1000° C. lower (depending on the mixture ratio) than in the conventional case.

This makes it possible to increase the output per single cylinder of the internal combustion engine for the following reasons, making it easy to increase the capacity.

(1) There is no need for complicated and fragile structures such as cooling reservoirs for cylinders and cylinder heads, and a large allowable stress can be achieved both in terms of materials and structure.

(2) There is no intake valve, there is no restriction due to pressure loss in the intake passage, and both fuel and air (or oxygen) are supplied in liquid form, so the supply capacity can be extremely large - (3) Same as increasing the compression ratio. In order to achieve this effect, even if the amount of air supplied is increased, unstable phenomena such as knocking do not occur, so a high-output engine can be realized. Since the air liquefaction device can be installed separately, it is easy to increase the amount of air supplied.

It should be noted that the above-mentioned air liquefaction device based on the conventional technology is sufficient; in particular, in recent years, a heleam liquefaction device for superconducting circuits has been developed, and by using this, a small-sized air liquefaction device can be easily obtained.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing a main part of a two-cycle engine according to one embodiment of the present invention in cross section, and FIG. 2 is an explanatory diagram showing a main part of a two-cycle engine according to another embodiment of the present invention in cross section. It is a diagram. DESCRIPTION OF SYMBOLS 1... Cylinder, 2... Piston, 3... Cylinder head, 5... Exhaust valve, 14... Fuel control valve, 1
5...Fuel spray nozzle, 16...Liquid air supply device, 19...Liquid air injection opening/closing valve, 20...Liquid air injection nozzle. (9)

Claims (1)

[Scope of Claim] A liquid air injection nozzle provided in the first and seventh ring heads and supplied with liquid air from a liquid air supply device. A two-stroke internal combustion engine characterized by comprising a liquid air injection on/off valve provided on the liquid air injection nozzle to open and close the nozzle, and a fuel spray nozzle and an exhaust valve each having a fuel control valve provided on the cylinder head. institution.