Gas injector for the direct injection of gaseous fuel into a combustion chamber

Patent metadata

Field	Value
Publication number	US-9810179-B2
Application number	US-201514599071-A
Country	US
Kind code	B2
Filing date	Jan 16, 2015
Priority date	Jan 17, 2014
Publication date	Nov 7, 2017
Grant date	Nov 7, 2017

Abstract

A gas injector for the direct injection of gaseous fuel into a combustion chamber of an internal combustion engine, including a valve seat, a valve needle, which in response to a lift releases a first cross-sectional area at the valve seat, and a gas control region, which is situated at the valve needle and defines a second cross-sectional area together with a component surrounding the valve needle, and in response to a lift, a change in the first cross-sectional area at the valve seat differs from a change in the second cross-sectional area at the gas control region.

First claim

What is claimed is:

1. A gas injector for directly injecting gaseous fuel into a combustion chamber of an internal combustion engine, comprising:
a valve seat;
a valve needle, which releases a first cross-sectional area at the valve seat in a lift; and
a gas control region situated at the valve needle and which defines a second cross-sectional area together with a component surrounding the valve needle;
wherein in response to a lift, a change in the first cross-sectional area at the valve seat differs from a change in the second cross-sectional area at the gas control region, and
wherein downstream from the gas control region in a flow direction, the gas injector has a space having a larger radius than a radius of the valve seat, so that once a predefined lift has occurred at the gas control region, the gas control region has no effect on an overall cross-sectional area for the injection of the gaseous fuel.

2. The injector of claim 1 , wherein the second cross-sectional area at the gas-control region is constant up to a predefined lift length at the start of a lift of the valve needle.

3. The injector of claim 1 , wherein the gas control region has a control edge, which has an annular shape.

4. The injector of claim 3 , wherein the control edge has a larger diameter than a diameter of the valve seat.

5. The injector of claim 1 , wherein the gas control region is configured in the form of a star or petals with a multitude of radially outwardly directed jags.

6. The injector of claim 1 , wherein the gas control region has through recesses or in which subregions have been removed at the control edge of the gas control region.

7. The injector of claim 1 , wherein the component surrounding the valve needle is a housing of the gas injector.

8. The injector of claim 1 , further comprising:
a sealing element disposed at the gas control region of the valve needle or disposed at the component surrounding the valve needle to form a pre-valve.

9. The injector of claim 1 , wherein at least one of the following is satisfied: (i) a cross-sectional area for the ejection of gas at the valve seat is in a range of 2 mm 2 to 6 mm 2 , and (ii) a diameter of the annular control edge is in a range of 7 mm 2 to 20 mm 2 .

10. The injector of claim 1 , wherein an emerging gas mass flow is in the range from 5 g/s to 15 g/s.

11. The injector of claim 1 , further comprising:
a sealing element, which includes an elastomer, disposed at the gas control region of the valve needle or disposed at the component surrounding the valve needle to form a pre-valve.

12. The injector of claim 11 , wherein the gas control region is configured in the form of a star or petals with a multitude of radially outwardly directed jags.

13. The injector of claim 11 , wherein the gas control region has through recesses or in which subregions have been removed at the control edge of the gas control region.

14. The injector of claim 1 , wherein the second cross-sectional area at the gas-control region is constant up to a predefined lift length at the start of a lift of the valve needle, and wherein the gas control region has a control edge, which has an annular shape.

15. The injector of claim 14 , wherein the control edge has a larger diameter than a diameter of the valve seat.

16. The injector of claim 14 , wherein at least one of the following is satisfied: (i) a cross-sectional area for the ejection of gas at the valve seat is in a range of 2 mm 2 to 6 mm 2 , and (ii) a diameter of the annular control edge is in a range of 7 mm 2 to 20 mm 2 .

17. The injector of claim 14 , further comprising:
a sealing element disposed at the gas control region of the valve needle or disposed at the component surrounding the valve needle to form a pre-valve;
wherein the component surrounding the valve needle is a housing of the gas injector.

18. The injector of claim 14 , further comprising:
a sealing element, which includes an elastomer, disposed at the gas control region of the valve needle or disposed at the component surrounding the valve needle to form a pre-valve;
wherein the component surrounding the valve needle is a housing of the gas injector.

19. The injector of claim 14 , wherein an emerging gas mass flow is in the range from 5 g/s to 15 g/s.

Assignees

• Bosch Gmbh Robert

Inventors

• Jaegle Felix
• Ohlhafer Olaf
• Schoefer Joerg
• Giezendanner-Thoben Robert

Classifications

• F02M45/08

  Injectors peculiar thereto · CPC title

• F02M21/0269

  Outwardly opening valves, e.g. poppet valves · CPC title

• F02M45/12

  providing a continuous {cyclic} delivery with variable pressure · CPC title

• F02M21/0275 Primary

  for in-cylinder direct injection, e.g. injector combined with spark plug · CPC title

• F02M21/0263 Primary

  Inwardly opening single or multi nozzle valves, e.g. needle valves · CPC title