Combustion chamber, method for igniting a fuel-air mixture in a combustion chamber of an internal combustion engine and internal combustion engine

Abstract

An ignition chamber of a combustion engine, the ignition chamber comprising: a piston having a piston bottom surface and a cylinder head having a cylinder head surface, the ignition chamber having an ignition chamber axis wherein one of said piston bottom surface and said cylinder head surface includes at least one depression and an ignition device is disposed in said ignition chamber and extends along said ignition chamber axis, said ignition device is configured to cause a cylindrical ignition impulse along said ignition chamber axis so as to create radial impulse components that are redirected by said depression so as to move in a direction longitudinal to said combustion chamber axis.

Claims

1. A combustion chamber of an internal combustion engine, the combustion chamber comprising: a piston including a piston top surface; a cylinder head including a cylinder head surface; and a combustion chamber axis, wherein the piston top surface or the cylinder head surface include at least one depression, wherein the at least one depression substantially forms the combustion chamber when the piston is at a top dead center, wherein the at least one depression is arranged in unobstructed facing relation to another of the piston top surface and the cylinder head surface, wherein the at least one depression has at least a partially conical shape, wherein an ignition device is arranged along the combustion chamber axis or parallel to the combustion chamber axis, wherein the ignition device is arranged in unobstructed facing relation to the at least one depression in a radial direction of the combustion chamber axis, and wherein the ignition device is configured to initiate a cylindrical ignition impulse in the at least one depression along the combustion chamber axis or parallel to the combustion chamber axis so that the cylindrical ignition impulse propagates essentially only with radial ignition impulse components from the ignition device to the piston top surface or the cylinder head surface.

2. The combustion chamber according to claim 1, wherein the at least one depression is configured in the cylinder head wherein the at least one depression is shaped as a cone whose tip is not oriented towards the piston top surface and the ignition device is positioned in the tip of the cone, or wherein the at least one depression is configured in the cylinder head wherein the at least one depression is shaped as a truncated cone whose upper surface is not oriented towards the piston top surface of piston and the ignition device is positioned in a center of an upper surface of the truncated cone, or wherein the at least one depression is configured in the cylinder head wherein the at least one depression includes a step generated by a combination between a cone and at least one truncated cone or by a combination of at least two truncated cones, wherein the ignition device is positioned at a tip of the cone or in a center of a upper surface of the truncated cone, wherein an angle between a piston top surface that is orthogonal to the combustion chamber axis and a generatrix of the cone and of the truncated cone is 40-50 so that the radial ignition impulse components are reflected by the depression into a direction that is parallel to the combustion chamber axis.

3. The combustion chamber according to claim 1, wherein the at least one depression is configured in the piston top surface wherein the at least one depression is shaped as a cone whose tip is not oriented towards the cylinder head and the ignition device is positioned in a center of a flat surface of the cylinder head, or wherein the at least one depression is configured in the piston top surface, wherein the at least one depression is shaped as a truncated cone, whose upper surface is not oriented towards the cylinder head and the ignition device is positioned in a center of a flat surface of the cylinder head, or wherein the at least one depression is configured in the piston top surface wherein the at least one depression includes a step generated by a combination between a cone and at least one truncated cone or by a combination of at least two truncated cones wherein the ignition device is positioned at a tip of the cone or in a center of an upper surface of the truncated cone, wherein an angle between the cylinder head surface and a generatrix of the cone or the truncated cone is of 40-50, so that the radial ignition impulse components are reflected by the depression into a direction that is parallel to the combustion chamber axis.

4. The combustion chamber according to claim 1, wherein the ignition device is a spark plug, a glow plug or a laser spark plug.

5. The combustion chamber according to claim 1, wherein the ignition device is configured initiate the cylindrical ignition impulse of a fuel-air mixture simultaneously along an entire axis of the at least one depression, or wherein the ignition device is configured so that an extension of a linear ignition length along the combustion chamber axis is 90% of an axial combustion chamber height.

6. The combustion chamber according to claim 2, wherein a clear height of the combustion chamber axis is arranged within the at least one depression.

7. The combustion chamber according to claim 2, wherein a radius of a bottom surface of the cone is smaller than or equal to a cylinder radius.

8. The combustion chamber according to claim 2, wherein a radius of a bottom surface of the truncated cone is smaller than or equal to a cylinder radius.

9. The combustion chamber according to claim 1, wherein at least one injection device is provided for an injection of air or fuel, wherein at least one of the at least one injection device is oriented so that an injection direction does not coincide with the combustion chamber axis, wherein an injection direction is oriented at an angle of 30 to 150 relative to the combustion chamber axis.

10. The combustion chamber according to claim 1, wherein an injection device for air and an injection device for fuel are disposed symmetrically with respect to the combustion chamber axis, and wherein an injection direction of the injection device for air and an injection direction of the injection device for fuel are arranged on one axis.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The characteristics of the present invention and other advantages shall be clarified hereunder by description of preferred execution examples. The explanation of the invention is done by means of the following purely schematic figures:

(2) FIG. 1 Shows the longitudinal section through the combustion chamber formed by the plane piston bottom surface and by the depression in the cylinder head; the depression has the form of a cone, and the ignition trigger is on the cone axis;

(3) FIG. 2 Shows a combustion chamber consisting in the upper cylinder head surface and in the depression in the form of a truncated cone in the piston bottom surface

(4) FIG. 3 Shows a combustion chamber formed by the plane piston bottom surface and by the stepped depression in the cylinder head, as well as the longitudinal section of the combustion chamber;

(5) FIG. 4 Shows a combustion chamber formed by the plane cylinder head surface and by the stepped depression in the piston bottom surface, as well as the longitudinal section of the combustion chamber;

(6) FIG. 5 Shows a combustion chamber formed by the plane piston bottom surface as well as from a combination between the central depression and the circular groove in the cylinder head; the depressions in longitudinal section have a triangular form, the FIG. 6 represents the circular-cylindrical element in the groove (this figure also shows the longitudinal section of the combustion chamber, formed by seven conic depressions in the piston bottom or in the cylinder head).

(7) FIG. 6 Shows a combustion chamber consisting of the plane cylinder head surface as well as from a combination between the central depression and the circular groove in the piston bottom; in longitudinal section the depressions have a stepped form (this figure also shows the longitudinal section of the combustion chamber, formed by seven conic depressions in the piston bottom or in the cylinder head).

(8) FIG. 7 Shows the longitudinal section of the combustion chamber presented in FIG. 6 (the combination between the central depression and the circular groove).

(9) FIG. 8 Shows a combustion chamber consisting of the plane piston bottom surface and the cylinder head with seven conic depressions, as well as the longitudinal section of the combustion chamber (the central longitudinal section of this combustion chamber is represented in FIG. 5).

(10) FIGS. 9 to 11 Show various configurations with regard to the injection collocation.

(11) FIGS. 12 to 15 Show various configurations with regard to the ignition trigger

DETAILED DESCRIPTION OF THE INVENTION

(12) It can be clearly seen that the combustion chamber of the combustion engine as described in the invention shows a cylinder 1 and a piston 2. The combustion chamber is formed by the plane surface of the piston bottom 2 and the depression 3 in the cylinder head (see, for instance, FIG. 1). The combustion chamber can also be formed by the plane surface of the cylinder head 1 and the depression 4 in the piston bottom (see, for instance, FIG. 2). Alternatively (not shown), depressions in the piston 2 and in the cylinder head 1 can be combined.

(13) Each of the depressions 3 and 4 has the form of a cone, of a truncated cone or of a step. The depressions 3 and 4 can also be configured as a spiral or circular groove, which has, in longitudinal section of the combustion chamber, a triangular, trapezoidal or stepped form or which is limited by a semicircle or by an arch.

(14) The surfaces of combustion chamber walls 5 are manufactured with maximum smoothness, for the reflection of the shock effect. Also foreseen are ignition triggers 6, 6a, 6b and the combustion chamber has a combustion chamber axis 7. In FIGS. 1 to 4 it can be noted that the ignition trigger 6 for the fuel-air mixture is positioned on the depression axis.

(15) The optimal angle to be installed between the piston head or the cylinder head and the generatrix of the cone or of the truncated cone is of 40-50. If the angle is decreased below 40 or increased in excess of 50, the effectiveness of the transformation of the kinetic energy of the fuel molecule into useful work.

(16) The invention functions as follows. Let us consider the following variant: the conic depression determines, at an angle of 45 between the plane surface and the generatrix of the cone, the concomitant ignition of the fuel-air mixture by use of an extended glow plug or with the ignition trigger (metal rod with high thermal capacity.

(17) The ignition of the fuel-air mixture with the glow plug alone or with the combined ignition trigger 6a, 6b alongside the combustion chamber axis 7 when using a laser beam or a glow plug lends to the fuel molecules (the molecules of the combustion products) a radial movement direction in relation to the ignition line. After reflection on the depression wall 5 under an angle of 45, the molecules continue their motion alongside the direction of the piston movement on parallel, non-intersecting movement tracks, are then reflected by the plane surface and resume their movement in the direction of the conic depression: this happens several times in the course of a cycle. No contact takes place between the fuel molecules and the surface of the cylinder wall, i.e. all the molecules do useful work. As the distances covered by the molecules in the course of a time unit are equal, the molecules move in a narrow front parallel to the plane surface of the piston bottom or cylinder head, which prevents their possible collisions and the chaotization of the system within a long period of time that exceeds significantly the cycle time of the engine. The resulting electromagnetic and shock waves as well as the high-energy gas particles are reflected by the smooth surface 5 of the combustion chamber, whereby its heating decreases and an effective transformation of the kinetic energy both of the gas and of the waves into useful work is guaranteed. In this manner, the pressure on the piston is significantly increased and the heating of the cylinder block of the combustion engine is significantly decreased, which results in the extension of its lifecycle.

(18) In FIG. 9, the collocation of the ignition device 6 in the cylinder head 1, configured as a long glow plug, of an injection nozzle 8 for air and of an injection nozzle 9 for the diesel fuel, is presented. It can be seen that the injection nozzles 8, 9 are disposed symmetrically, with the injection directions on a line 10. This line 10 is disposed perpendicularly to the combustion chamber axis 7. In this manner, the maximum effect is achieved, as the created fuel-air mixture already shows radial impulse parts in relation to the combustion chamber axis 7 and, apart from this, the mixture picture is configured very symmetrically and the mixture parts are very finely pulverized by the collision between air and fuel, which also leads to better combustion.

(19) In FIG. 10, the two injection nozzles 8, 9 are not disposed perpendicularly, but rather under an acute angle a in relation to the combustion chamber axis 7. Here too, a positive effect is created, because the fuel-air mixture shows radial impulse parts.

(20) While FIGS. 9 and 10 show a combustion chamber geometry with a depression 3 in the cylinder head 1, FIG. 11 shows a combustion chamber geometry with a depression 4 in the piston 2, whereby the injection nozzles 8, 9 are again not disposed perpendicularly, but rather under an acute angle a in relation to the combustion chamber axis 7.

(21) In FIGS. 12 to 15, various ignition trigger variants are shown in further detail in relation with different combustion chamber geometries, whereby in FIGS. 12 and 14 depression 3 is positioned in the cylinder head 1 and in FIGS. 13 and 15 depression 4 is positioned in the piston bottom 2. In FIGS. 12 and 13, the ignition trigger 6 is configured as a short glow plug with a long rod 6b, whereas in FIGS. 14 and 15 the ignition trigger is configured as a long glow plug with a short rod 6b.

(22) When starting the diesel engine, the glow plug 6a serves as an ignition auxiliary and, in operation, glow plug 6a and rod 6b act together as ignition trigger 6 for inducing self-ignition on the combustion chamber axis. Together, glow plug 6a and rod 6b essentially cover the entire combustion chamber axis, so that a complete cylinder-shaped impulse distribution results. If rod 6b is omitted or shortened, this effect is diminished, while the invention foresees that self-ignition takes place linearly alongside of a part of the combustion chamber axis.