Valve ignition prechamber

1. A valve ignition prechamber ( 1 ) for an internal combustion engine ( 2 ) which comprises a cylinder head ( 3 ) which caps a cylinder ( 4 ) to form a combustion chamber ( 5 ) in which a main load can be burned ( 30 ), the valve ignition prechamber comprising:

at least one lamination cavity ( 6 ) which is arranged in the cylinder head ( 3 ) and is connected to the combustion chamber ( 5 ) by a lamination duct ( 7 ) and which also receives a lamination injector ( 8 ) which can directly or indirectly inject into said cavity ( 6 ) a pilot load ( 9 ) previously pressurized by compression means ( 10 ), said load ( 9 ) consisting of a combustive agent-AF fuel mixture easily flammable by means of a spark;

ignition means ( 11 ) which open into the lamination cavity ( 6 ) and which can ignite the pilot load ( 9 );

a lamination valve ( 13 ) which can close all or part of the lamination duct ( 7 ) and which exposes both a cavity side face ( 14 ) subjected to the pressure of the gases prevailing in the lamination cavity ( 6 ), as well as a chamber side face ( 15 ) subjected to the pressure of the gases prevailing in the combustion chamber ( 11 ), said lamination valve ( 13 ) being able to translate with respect to said duct ( 7 ) under the effect of the pressure of the gases, either towards the lamination cavity ( 6 ) when said pressure prevailing in the latter is lower than the pressure prevailing in the combustion chamber ( 5 ), or towards said chamber ( 5 ) when the pressure prevailing in the latter is lower than the pressure prevailing in lamination cavity ( 6 );

at least one cavity side valve stop ( 16 ) which determines the position of the lamination valve ( 13 ) closest to the lamination cavity ( 6 ); and

at least one chamber side valve stop ( 17 ) which determines the position of the lamination valve ( 13 ) closest to the combustion chamber ( 5 ), said chamber side valve stop ( 17 ) comprising a valve opening seat ( 20 ) arranged in the lamination duct ( 7 ) or at either end of said duct ( 7 ), said valve opening seat ( 20 ) cooperating with a chamber side valve bearing surface ( 21 ) located at the periphery and/or at the end of the lamination valve ( 13 ), so that said valve opening seat ( 20 ) and said chamber side valve bearing surface ( 21 ) are in contact with each other, the lamination valve ( 13 ) forming with the lamination duct ( 7 ) a torch ignition prechamber ( 23 ) which simultaneously communicates with the lamination cavity ( 6 ) and with the combustion chamber ( 5 ) through at least one gas ejection hole ( 24 ).

2. The valve ignition prechamber according to claim 1 , wherein the lamination valve ( 13 ) closes all or part of the lamination duct ( 7 ) when the lamination valve ( 13 ) is closest to the lamination cavity ( 6 ) while the lamination valve ( 13 ) opens said duct ( 7 ) on a wider section when the lamination valve ( 13 ) is positioned closest to the combustion chamber ( 5 ).

3. The valve ignition prechamber according to claim 1 , wherein the cavity side valve stop ( 16 ) consists of a valve closing seat ( 18 ) arranged in the lamination duct ( 7 ) or at either end of said duct ( 7 ), said seat ( 18 ) cooperating with a cavity side valve seat ( 19 ) located at the periphery and/or at the end of the lamination valve ( 13 ).

4. The valve ignition prechamber according to claim 3 , wherein the valve closing seat ( 18 ) and the cavity side valve bearing surface ( 19 ) create a seal when they are in contact with each other, said seal preventing any gas from passing at said contact when the pressure prevailing in the combustion chamber ( 5 ) is greater than the pressure prevailing in the lamination cavity ( 6 ).

5. The valve ignition prechamber according to claim 1 , wherein the valve opening seat ( 20 ) and the chamber side valve bearing surface ( 21 ) create a seal when they are in contact with each other so as to prevent any gas from passing at said contact.

6. The valve ignition prechamber according to claim 1 , wherein a periphery of the lamination valve ( 13 ) comprises guiding means ( 22 ) which maintain said lamination valve ( 13 ) approximately centered in the lamination duct ( 7 ), and approximately in the same longitudinal orientation as said duct ( 7 ), regardless of the axial position of said lamination valve ( 13 ) with respect to said duct ( 7 ).

7. The valve ignition prechamber according to claim 1 , wherein the internal peripheral wall of the torch ignition prechamber ( 23 ) is cylindrical while the lamination valve ( 13 ) has a circular periphery and is housed at low radial clearance in said prechamber ( 23 ).

8. The valve ignition prechamber according to claim 1 , wherein the lamination duct ( 7 ) opens projecting into the combustion chamber ( 5 ) in the form of a protruding ejection dome ( 25 ) which houses the torch ignition prechamber ( 23 ) and from which the gas ejection hole ( 24 ) opens.

9. The valve ignition prechamber according to claim 8 , wherein the valve opening seat ( 20 ) is arranged in the protruding ejection dome ( 25 ).

10. The valve ignition prechamber according to claim 1 , wherein when the lamination valve ( 13 ) is positioned close to the combustion chamber ( 5 ), that is to say, in the vicinity or even in contact with the chamber side valve stop ( 17 ) with which the lamination valve ( 13 ) cooperates, said lamination valve ( 13 ) uncovers at least one gas ejection hole ( 24 ) which connects the lamination cavity ( 6 ) to the combustion chamber ( 5 ).

11. The valve ignition prechamber according to claim 1 , wherein the ignition means ( 11 ) consist of a spark plug ( 12 ) which closes the first end of a perforated connecting tube ( 26 ) which traverses all or part of the internal volume of the lamination cavity ( 6 ) and whose body is radially traversed by at least one radial slot ( 27 ) which connects the inside of said tube ( 26 ) with said internal volume, while the second end of said tube ( 26 ) receives the lamination duct ( 7 ) and the lamination valve ( 13 ), and while the central electrode ( 40 ) and the ground electrode ( 39 ) of said spark plug ( 12 ) are housed inside the perforated connecting tube ( 26 ).

12. The valve ignition prechamber according to claim 1 , wherein the cavity side face ( 14 ) exposes an aerodynamic dome ( 29 ).

13. The valve ignition prechamber according to claim 1 , wherein the cavity side face ( 14 ) forms a ground electrode ( 39 ) which faces a central electrode ( 40 ) comprised by a spark plug ( 12 ), the spark plug ( 12 ) constituting the ignition means ( 11 ).

14. The valve ignition prechamber according to claim 3 , wherein the chamber side valve stop ( 17 ) consists of a valve opening seat ( 20 ) arranged in the lamination duct ( 7 ) or at either end of said duct ( 7 ), said seat ( 32 ) cooperating with a chamber side valve bearing surface ( 21 ) located at the periphery and/or at the end of the lamination valve ( 13 ), and wherein the lamination valve ( 13 ) is axially thicker at a periphery the lamination valve ( 13 ) which receives the cavity side valve bearing surface ( 19 ) and the chamber side valve bearing surface ( 21 ), than at a center of the lamination valve ( 13 ).