WO1992014040A1

WO1992014040A1 - The method of a valve timing of a four-stroke internal combustion engine and the valve timing mechanism device of a four-stroke internal combustion engine

Info

Publication number: WO1992014040A1
Application number: PCT/PL1992/000003
Authority: WO
Inventors: Piotr Marszalkiewicz
Original assignee: Piotr Marszalkiewicz
Priority date: 1991-02-07
Filing date: 1992-02-04
Publication date: 1992-08-20
Also published as: PL288988A1; AU1184492A

Abstract

The method of a valve timing of a four-stroke internal combustion engine and a valve timing mechanism device have a purpose to improve the filling of a cylinder with a charge and efficient removal of exhaust gases due to that, that both the inlet of the charge to the cylinder and the outlet of the exhaust gases is performed alternatively through all the cylinder valves. The inlet of the charge to the cylinder and the outlet of the exhaust gases is performed alternatively through the common intermediate chamber (4) connected to the intake manifold (1) through the intake valves (2), to exhaust manifold (7) through the exhaust valves (3) and to the total cylinder volume (6) through the main valves (5) controlling the inlet of the charge thereto or outlet of the exhaust gases, while the number of the main valves, preferable of poppet-type belonging to each cylinder is optional and this function can be also fulfilled by one main valve (5) only. Application to all kinds of piston internal combustion engines working according to a four-stroke cycle.

Description

DESCRIPTION OF INVENTION

Title of invention

The method of a valve timing of a four -stroke internal combustion engine and the valve timing mechanism device of a four-stroke internal combustion engine.

Field of technology

The invention refers to the method of a valve timing of a four -stroke internal combustion engine, that is to say , to the method of delivering a charge to an engine cylinder and removing exhaust gases and controlling these processes in accordance with a four -stroke circle, and also to the valve timing mechanism device comprising a system of valves that control an inlet of charge to a total cylinder volume and control an outlet of the exhaust gases from the said volume by the method according to the invention.

State of art of technology

The most frequently used method of the valve timing of four-stroke internal combustion engine is a valve timing with poppet valves. Heads of such engines are provided with at least one intake valve and one exhaust valve for each cylinder. By opening or closing in a strictly synchronised method the intake valve control the inlet of a charge from the intake manifold to the total cylinder volume while exhaust valve control the outlet of the exhaust gases from the total cylinder volume to the exhaust manifold. The charge can consist of air or air- fuel mixture. The performance of internal combustion engine depends considerably on the amount of the charge delivered to the total cylinder volume expressed with the filling factor and also on the efficiency of removing the exhaust gases from the cylinder. The parameter that restricts replacement of the charge and removal of the exhaust gases both quantitatively and qualitatively is the size of intake and exhaust holes in the cylinder head that are opened and closed with the valves through which the movement of the charge and exhaust gases takes place. In order to improve the filling of the cylinder with the charge and to remove the exhaust gases in more efficient way there are used multiple -valve heads with multiplied quantity of valves in each cylinder, e.g. - two intake valves and one exhaust valve,

- two intake valves and two exhaust valves,

- three intake valves and two or three exhaust valves in extremely technologically sophisticated designs.

Increasing the number of valves in the cylinder is technologically difficult due to the size restrictions of the combustion chamber, design problems of the valve drive and results in a slight increase of the efficiency of the cylinder filling and emptying since the flow of gases through the valves and walls of the combustion chamber, that are closed to each other , is disturbed. Even in such complicated designs like cylinder heads with five or six valves for each cylinder, the need to find room in the combustion chamber for the intake and exhaust valves simultaneously, limits the flow cross-section both for the charge and exhaust gases and does not improve the filling and emptying of the cylinder substantially.

Disclose of invention

The method and the device according to the invention have to ensure the delivery of greater amount of the charge to the total cylinder volume and to remove the exhaust gases more efficiently than in the known designs. The essence of the method and device according to the invention consists in that the total cylinder volume is connected to a device delivering the charge and to a device receiving the exhaust gases through a common intermediate chamber. The intermediate chamber is connected to the total cylinder volume through main valves, to the intake manifold through the intake valves and to the exhaust manifold through the exhaust valves. Through the main valves there is performed alternating inlet of the charge from the intermediate chamber to the total cylinder volume or outlet of exhaust gases from the total cylinder volume to the intermediate chamber; the number of these valves preferably poppet valves is facultative and this goals can be fulfilled also by one main valve only of properly large size for a given cross- flow section. The number and type of design of the intake and exhaust valves for each cylinder are facultative. Opening and closing of the main, intake and exhaust valves is mutually synchronized in the way ensuring accomplishment of succeeding working strokes of the engine. The method of the valve timing according to the invention is shown schematically in the drawing in which fig. 1 shows the succeeding strokes of the four -strokes internal combustion engine.

- the intake stroke is performed in such a way that during the piston movement from T.D.C. to B.D.C., the charge gets from the intake manifold through the open intake valves 2, with the exhaust valves 3 closed, into intermediate chamber 4 and further through the open main valves 5 to the total cylinder volume 6;

- the compression stroke is performed in such a way that with the intake valves 2 and exhaust valves 3 at any operation position and the main valves 5 closed, the total cylinder volume 6_ is closed making it possible the compression of the charge by the piston moving from B.D.C. to T.D.C.;

- the working stroke is performed in such a way that, with the intake valves 2 and exhaust valves 3_ at any position and with the main valves 5 closed, the charge compressed in the total cylinder volume 6 is ignited and causes the piston movement from T.D.C. to B.D.C.;

- the exhaust stroke is performed in such a way that with the piston movement from B.D.C. to T.D.C., the exhaust gases are passed from the total cylinder volume 6 through the open main valves 5 to the intermediate chamber 4 and from here, with the intake valves 2 closed are fed through the open exhaust valves 3 to the exhaust manifold 7.

As compared with the known solutions of the valve timing of four -stroke internal combustion engines with the so called multiple- valve heads with, for example four, five or six valves for one cylinder, where inlet of the charge is performed only through two or three inlet valves while the exhaust through two or three exhaust valves, the method according to the invention makes it possible the inlet of the charge to the total cylinder volume and removing the exhaust gases from the total cylinder volume through all the valves existing in the cylinder e.g. in the head according to the invention with four main valves for each cylinder - through all four valves, so that the filling factor of the cylinder and the efficiency of removing the exhaust gases are improved substantially.

Description to the figures of the drawing

Fig.l - Method of valve timing according to the invention formulated schematically. Fig.2 and Fig.3 - Example of implementation of the valve timing mechanism device according to the invention for a Diesel engine.

Fig.4 and Fig.5 - Example of implementation of valve timing mechanism device according to the invention for a spark -ignition engine.

The best ways of implementation of the invention The device according to the invention working in compliance with the method according to the invention is shown in the example of implementation of the valve timing system of the four -stroke Diesel engine with a direct injection illustrated in the drawing in which fig.2 shows a vertical section of a head while fig.3 shows a cross -section illustrating schematically the arrangement of the valves. The head comprises the intermediate chamber 8 limited in space by the walls of the head, poppet intake valves £, poppet exhaust valves 10 and the poppet main valve 11. Two intake valves 9 connect the intermediate chamber 8 to the intake manifold 12, two exhaust valves .10 connect the intermediate chamber 8 to the exhaust manifold 13, the single main valve .11 connects the intermediate chamber 8 to the total cylinder volume ,14. The intake valves 9, exhaust valves 10 as well as the main valve π. are set in motion by means of known devices in the way making the four -stroke cycle of the engine possible. In the fig.2 and fig.3 there is shown the working state of the valves during the exhaust stroke

Another modification of the device according to the invention working in compliance with the method according to the invention is presented in the example of implementation of a valve timing system of a four-stroke internal combustion spark- ignition engine with a fuel injection illustrated in the drawing in which fig.4 shows a vertical section of the head while fig.5 shows a cross-section illustrating the arrangement of the valves. The head comprises the intermediate chamber 15 limited in space with the head walls, poppet intake valve 16, poppet exhaust valve 17 and the poppet main valve 18. The single intake valve 16 connects the intermediate chamber 15 to the intake manifold 19, the single exhaust valve 17 connects the intermediate chamber 15 to the exhaust manifold 20 while the single main valve 18 connects the intermediate chamber 15 to the total cylinder volume 21. The intake valve 16, exhaust valve 17 and the main valve 18 are set in motion by means of known devices in the way making a four-stroke cycle of the engine possible. In fig.4 and fig.5 there is shown the working state of valves during the intake stroke.

Claims

PATENT CLAIMS

1. The method of a valve timing of a four-stroke internal combustion engine characteristic in that the inlet of a charge to a total cylinder volume and the outlet of exhaust gases from the total cylinder volume is performed alternatively through a common intermediate chamber connected to the total cylinder volume through main valves and to an intake manifold through intake valves and to an exhaust manifold through exhaust valves.

2. The method according to the claim 1, characteristic in that the inlet of the charge to the total cylinder volume or outlet of the exhaust gases from the total cylinder volume is performed through the main valves and the number of these valves for each cylinder is facultative and that these functions can be performed by one main valve only.

3. The method according to the claim 1, characteristic in that the functioning of the intake valves, exhaust valves and the main valves of known design and optional numbers of them for each cylinder, is synchronised in such a way that the intake stroke is performed with the exhaust valves closed and the intake valves as well as the main valves opened, the exhaust stroke is performed with the intake valves closed and the exhaust valves as well as the main valves opened, the compression stroke and the working stroke are performed with the main valves closed while the functional state of the intake valves and the exhaust valves is optional.

4. The valve timing mechanism device of the four-stroke internal combustion engine characteristic in that the intermediate chamber £8} positioned in the head above the total cylinder volume (14. is equipped in its lower part with a set of the main valves (11.. preferably of a poppet- type, connecting it to the total cylinder volume- (14) and in its upper part is equipped with a set of the intake valves £9) of known design, for example of a poppet- type, connecting it to the intake manifold (12. and with a set of the exhaust valves (10) of known design, e.g. of poppet- type, positioned opposite thereto and connecting it to the exhaust manifold (13).

5. The device according to the claim 4 characteristic in that the number of the main valves connecting the intermediate chamber £8} to the total cylinder volume (14) is optional and the function can be performed by one main valve (11) only.