SK8538Y1 - Method of fuel injection for combustion engines - Google Patents

Abstract

Fuel injection control for combustion engines by changing the fuel injection cycle (7) from regular to alternate and vice versa, according to the required motor power allows the engine to operate in a four-stroke power or eight stroke economy mode.

Description

The invention relates to a modification of a method of injecting fuel for internal combustion engines in the automotive industry.

BACKGROUND OF THE INVENTION

According to the state of the art, fuel (gasoline) enters the combustion chamber of the engine either by indirect injection into the intake manifold, or fuel (gasoline, diesel) is injected directly into the engine cylinders. The fuel injection mode is activated for the first cycle of the four-stroke indirect-injection internal combustion engine and for the second cycle for direct-injection engines. The four stroke cycle is the most commonly used type of internal combustion engine design.

According to the prior art, in Figure 1, the internal combustion engine operates in a four stroke cycle. In the first cycle of the internal combustion engine, the intake valve 1 is open. The piston 2 sucks air 3 into the cylinder 4. At the same time, the injection 5 of the fuel 7 by means of the injection nozzle 6 mixes the fuel 7 with the air 3 in the cylinder 4. In the second measure, all valves 1 and 9 are closed. The piston 2 compresses the fuel / air mixture 3 in the cylinder 4. Shortly before reaching the top dead center of the piston 2, the spark plug 8 ignites the fuel / air mixture 3. In the third cycle of the internal combustion engine, the valves 1 and 9 are closed. The mixture of fuel 7 and air 3 will burn, increasing the temperature in cylinder 4, applying pressure to the piston 2 and then pushing the piston 2 down - the engine operating cycle. In the fourth measure, the valve 9 is open. The flue gas 10 is forced out of the cylinder 4 by the piston 2.

However, the four-stroke internal combustion engine cannot change its stroke volume if (often) less power is required. For this reason, the engine is equipped with a throttle in the intake manifold that regulates the volume of air available to the engine to operate. An adequate amount of fuel is also injected into this air volume, typically 14: 1.

But such a throttle of the internal combustion engine creates resistance to the engine, ie energy loss. In addition, reducing the amount of intake air by the engine and consequently reducing the volume of injected fuel is limited because the fuel / air mixture in the cylinder needs to be reliably ignited. The combustion of an (extremely) lean fuel-air mixture generates additional pollutants in the exhaust gases caused by the operation of the internal combustion engine.

The essence of the technical solution

It is an object of the present invention to provide a fuel injection and combustion mode which, compared to the prior art, allows fuel economy and emissions reduction in the internal combustion engine. This objective can be achieved by reducing the number of fuel injection cycles in the internal combustion engine cylinder by 50% and consequently by reducing the number of operating cycles by 50%. The internal combustion engine of the present invention operates normally in four such with regular injection at high load, but at low load, the engine operates on an eight-stroke cycle with alternate fuel injection. If the four-cylinder internal combustion engine operates in a four-stroke cycle, it reaches 100 engine strokes in one second at 3000 rpm. Under the same conditions, the engine shall be operated in an eight - stroke cycle 50.

In an eight-stroke cycle, the engine operates in the first four such (1-4) as in the four-stroke cycle, but the other four such (5-8) no longer inject fuel into the engine cylinders. The engine in the fifth to eight stroke works without fuel, only with air.

After starting the internal combustion engine works first in a four-stroke cycle. The eight-stroke cycle is only activated when the engine reaches operating temperature (especially in winter) and high engine power is not required. At a steady speed of a car on a highway, on a county road, or a slow ride in a city, the engine operates in an eight-stroke cycle. If higher engine power is required, eg. when overtaking another vehicle, the driver pushes the accelerator pedal and the ECU automatically changes the cycle to four stroke by changing the fuel injection.

Overview of the figures in the drawings

In the accompanying drawings, FIG. 1 of the prior art. In FIG. 2 is the operation of an internal combustion engine operating in an eight-stroke cycle.

N E 8538 Υ1

EXAMPLES

Referring to Figure 2, the internal combustion engine can operate in four such or even eight such as desired. In an eight-stroke cycle (at low load) in the first cycle, the engine intake valve 1 is open and the piston 2 sucks air 3 into the cylinder 4. The nozzle 6 injects 5 fuel 7 which is mixed with the air 3 in the cylinder 4. valves 1 and 9 closed. The piston 2 compresses the fuel / air mixture 3 in the cylinder 4. Shortly before reaching the top dead center of the piston 2, the spark plug 8 ignites the fuel / air mixture 3. In the third cycle of the internal combustion engine, the valves 1 and 9 are closed. The mixture of fuel 7 and air 3 will burn, raise the temperature in the cylinder 4, apply pressure to the piston 2, and then push the piston 2 down - the working cycle of the engine. In the fourth step, the exhaust valve 9 is open. The flue gas 10 is forced out of the cylinder 4 by the piston 2.

In the fifth cycle of the internal combustion engine, the intake valve 1 is open and the piston 2 only sucks air 3 into the cylinder 4. The nozzle 6 remains closed. No fuel enters cylinder 4. In the sixth measure, valves 1 and 9 are closed. The piston 2 only compresses the fuel-free air 3 in the cylinder 4. In the seventh cycle, the valves 1 and 9 are closed. The piston 2 is directed downwardly pushed only by compressed air 3, the expansion proceeds without combustion. In the eighth measure, the exhaust valve 9 is open, the piston 2 forces air 3 out of the cylinder 4 out.

In a four stroke cycle every 4 turns of the engine crankshaft, fuel is injected 2 times, in an eight stroke cycle only 1 time. At a low power requirement, the eight-stroke engine nozzle 6 injects 15-20% more fuel 7 into the cylinder 4 than in the four-stroke engine. 1, but injects the fuel 7 only once. This allows fuel to be reliably ignited even in small amounts, resulting in a reduction in exhaust emissions and a 30% reduction in fuel consumption.

This technology allows you to:

- also burn small quantities of fuel, which otherwise can be reliably ignited in a four-stroke cycle at low engine load without increasing exhaust emissions,

- the eight-stroke cycle also replaces the technically demanding de-coupling (deactivation) of cylinders in internal combustion engines used at low engine load,

- since the engine only operates with air in the fifth to eighth cycles, this results in additional cooling of the engine, especially the valves. In addition, the standard water cooling of the engine has twice the time to cool the combustion chamber of the engine in an eight-stroke cycle than in a four-stroke cycle. The reduced temperature in the combustion chamber of the engine has a positive effect on the reduction of fuel consumption and the generation of exhaust emissions.

The internal combustion engine for a regular four-stroke and alternating eight-stroke fuel injection cycle does not need any modification in its design. It is sufficient to adjust the fuel injection mode in the ECU.

Industrial Usability

The internal combustion engine, which is capable of operating in both four-stroke and eight-stroke cycles, is designed for all types of motor vehicles. However, this technology is also designed for internal combustion engine generators that will only operate in a permanent eight-stroke energy saving cycle.

Claims (2)

A method of injecting fuel into an internal combustion engine, characterized in that the internal combustion engine operates in either a four-stroke power mode or an eight-stroke power mode to change fuel injection from regular to alternating and vice versa. 2. A method for injecting fuel into an internal combustion engine according to claim 1, wherein the internal combustion engine operates continuously in an economical eight-stroke cycle only with alternating fuel injection into the cylinders.