COMPRESSION IGNITED COMBUSTION ENGINE

Abstract

A compression ignited combustion engine has at least one cylinder and first and second gas intake ports in a cylinder head restricting a combustion chamber. One gas intake passage leads to the two ports and is widened in a Y-shaped end influencing gas entering each port into a tangential flow in opposite direction with respect to the flow into the other port. The first intake port is designed to allow gas entering this port to continue said tangential flow so as to enter the combustion chamber in a swirl in a first rotation direction, whereas the second intake port is designed to guide gas entering this port to also enter the combustion chamber in a swirl in said first rotation direction.

Claims

1. A compression ignited combustion engine comprising: at least one cylinder and first and second gases intake ports in a cylinder head restricting a combustion chamber of the cylinder, said intake ports opening into the combustion chamber; and one gases intake passage leading towards the two ports perpendicularly to a line along which these ports are arranged in the cylinder head beside each other and to both ports by being widened in the direction of said line while forming a Y-shaped end influencing gases entering each said port into a tangential flow in opposite direction with respect to the flow into the other port, wherein the first intake port is designed to allow gases entering this port to continue said tangential flow so as to enter the combustion chamber in a swirl in a first rotation direction, and that the second intake port is designed to guide gases entering this port to also enter the combustion chamber in a swirl in said first rotation direction.

2. An engine according to claim 1, wherein said second in-take port contains a guiding arrangement configured to guide at least a portion of gases entering this port into an helical flow to leave this port and enter the combustion chamber in a swirl in said first rotation direction.

3. An engine according to claim 2, wherein the guiding arrangement is configured to divide the second intake port into two parts, of which a first part is configured to guide gases entering the second intake port and flowing into the first part to continue said tangential flow and a second part provided with means configured to guide gases flowing into the second part to assume an helical flow, and that the guiding arrangement comprises a member making the flows in the first and second parts of the second intake port to meet in a region and there be joined into one helical flow rotating in said first rotation direction towards and into the combustion chamber.

4. An engine according to claim 3, wherein said second part has a shape of an helix extending towards the combustion chamber so as to guide gases entering this part to rotate around the axis of this helix in said first rotation direction.

5. An engine according to claim 4, wherein said second part contains a boss-like member and walls guiding said gases in a helical movement around the boss-like member.

6. An engine according to claim 3, wherein said member in the flow meeting region comprises an obstacle forcing gases of the tangential flow in said first part to join the helical flow in the second part into a helical flow.

7. An engine according to claim 6, wherein said member in the flow meeting region is a wedge configured to guide the tangential flow in said region at the end of said first part to join the helical flow in the second part into an helical flow to form a swirl in said first rotation direction moving towards and into the combustion chamber.

8. An engine according to claim 3, wherein said first part of the second intake port is an upper part more distant to an opening of the second intake port into the combustion chamber than the second part, and that said member in the flow meeting region is configured to guide the tangential flow in the first part down into the helical flow in the second part and together therewith create one helical flow downwards towards and into the combustion chamber.

9. An engine according to claim 3, wherein the cross-section of the second part decreases in the direction the gases flow therethrough towards the combustion chamber.

10. An engine according to claim 1, wherein openings of the first and second intake ports into the combustion chamber are located along a straight line in parallel with a crank shaft of the engine.

11. A motor vehicle comprising a compression ignited combustion engine comprising: at least one cylinder and first and second gases intake ports in a cylinder head restricting a combustion chamber of the cylinder, said intake ports opening into the combustion chamber; and one gases intake passage leading towards the two ports perpendicularly to a line along which these ports are arranged in the cylinder head beside each other and to both ports by being widened in the direction of said line while forming a Y-shaped end influencing gases entering each said port into a tangential flow in opposite direction with respect to the flow into the other port, wherein the first intake port is designed to allow gases entering this port to continue said tangential flow so as to enter the combustion chamber in a swirl in a first rotation direction, and that the second intake port is desiqned to guide gases entering this port to also enter the combustion chamber in a swirl in said first rotation direction.

12. A method of creating propulsion of a vehicle comprising using an engine comprising: at least one cylinder and first and second gases intake ports in a cylinder head restricting a combustion chamber of the cylinder, said intake ports opening into the combustion chamber; and one gases intake passage leading towards the two ports perpendicularly to a line along which these ports are arranged in the cylinder head beside each other and to both ports by being widened in the direction of said line while forming a Y-shaped end influencing gases entering each said port into a tangential flow in opposite direction with respect to the flow into the other port, wherein the first intake port is designed to allow gases entering this port to continue said tangential flow so as to enter the combustion chamber in a swirl in a first rotation direction, and that the second intake port is desiqned to guide gases entering this port to also enter the combustion chamber in a swirl in said first rotation direction.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] With reference to the appended drawings, below follows a specific description of an embodiment of the invention cited as an example.

[0023] In the drawings:

[0024] FIG. 1 illustrates very schematically the two intake ports and the cylinder of a compression ignited combustion engine according to the invention from above with intake air flows schematically indicated,

[0025] FIG. 2 is a schematic partially sectioned perspective view of the parts of the engine shown in FIG. 1,

[0026] FIG. 3 is a schematic view used for explaining the different parts of the two intake ports of the engine according to the invention,

[0027] FIG. 4 is a perspective view of the intake ports in the engine according to the invention,

[0028] FIG. 5 shows a cross-section through the centre of the valves of the intake ports of the engine according to the invention, and

[0029] FIG. 6 is a very simplified view illustrating an engine according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0030] The features of a compression ignited combustion engine 1 essential for the present invention will now be described while making reference to FIGS. 1-5. This engine is arranged in a motor vehicle 24 and has at least one cylinder 2 and first 3 and second 4 gas intake ports in a cylinder head 5 restricting a combustion chamber 6 of the cylinder. The first intake port 3 and the second intake port 4 open into the combustion chamber. One gas intake passage 7 leads towards the two ports perpendicularly to a line 8 along which these ports are arranged in the cylinder head 5 beside each other and to both ports by being widened in the direction of the line 8 while forming a Y-shaped end 9 influencing gas entering each port into a tangential flow as shown through the arrow A for the first intake port 3 in opposite direction with respect to the tangential flow into the second port 4. Tangential does here relate to the extension of the internal walls of the cylinder defining the combustion chamber.

[0031] The first intake port 3 is designed to allow gas entering this port to continue the tangential flow so as to enter the combustion chamber in a swirl 10 (see FIG. 2) in a first rotation direction.

[0032] The second intake port 4 is designed to guide gas entering this port to also enter the combustion chamber in a swirl in said first rotation direction, and how that may be obtained will now be disclosed. The first intake port has only one part 11 influencing gas entering this part into a tangential flow. The second intake port 4 is divided into two parts 12, 13 shown as separate parts in FIG. 3. These three parts 11-13 are combined into the intake port structure 14 shown in FIG. 3. A first part 12 of the second intake port being an upper part more distant to an opening of the second intake port into the combustion chamber than a second part 13 is configured to guide gas entering the second intake port 4 and flowing into this part 12 to continue the tangential flow, which accordingly will be in the opposite direction as shown through the arrow A for the flow through the first intake port. A second part 13 is provided with means configured to guide gases flowing into this part to assume a helical flow. This is obtained by the fact that the second part has a shape of a helix extending towards the combustion chamber, which is obtained by arranging a boss-like member 15 inside the second part 13 and walls guiding the gas in a helical movement around this boss-like member.

[0033] Furthermore, an obstacle in the form of a wedge 16 is arranged in a region 17 where the tangential flow in the first part 12 of the second intake port 4 and the helical flow in the second part 13 will meet. This wedge is configured to guide the tangential flow in the region 17 to join the helical flow in the second part 13 into a helical flow to form a swirl 18 in the first rotation direction moving towards and into the combustion chamber. Thus, the gas led to the second intake port is redirected as simplifiedly illustrated through the arrows B in FIG. 1 to generate a swirl with the same rotation direction as the swirl generated by the gas flowing through the first intake port 3.

[0034] The cross-section of the second part 13 of the second intake port and accordingly of said helix in this part decreases in the direction the gases flow therethrough towards the combustion engine as indicated through the regions 19 and 20 in FIG. 5, where the pitch of the helix is shown through the line 21.

[0035] FIG. 6 illustrates how the first intake port 3 and the second intake port 4 are located along a straight line 22 in parallel with a crank shaft 23 on the cold side of the engine 1, here shown to have four cylinders 2. The advantages of such a straight valve picture have been disclosed above.

[0036] The invention is of course in no way restricted to the embodiment described above, since many possibilities to modifications thereof are likely to be obvious to one skilled in the art without having to deviate from the scope of the invention defined in the appended claims.

[0037] The invention is not restricted to such an engine for any particular use and in industrial applications and in motor vehicles for propulsion thereof may be mentioned as examples of such a use. The most usual fuel to be combusted in such an engine is diesel, but other fuels are conceivable.