Valve and method for producing a valve

Patent metadata

Field	Value
Publication number	US-10415526-B2
Application number	US-201515327209-A
Country	US
Kind code	B2
Filing date	Jul 30, 2015
Priority date	Sep 2, 2014
Publication date	Sep 17, 2019
Grant date	Sep 17, 2019

Abstract

A valve is provided, in particular an injection valve, having a valve seat and a valve needle which extends along a closing direction for the most part, the valve seat having a valve-seat surface, and a valve-closing element is mounted on an end of the valve needle facing the valve seat, the valve-closing element being able to be moved between an open position and a closed position, and the valve-closing element together with the valve-seat surface forming a sealing seat in the closed position, the valve-closing element having a greater core hardness and/or surface hardness than the valve-seat surface.

First claim

What is claimed is:

1. A method for producing a valve, comprising:
in a first production step, developing a valve-closing element from a base body material;
in a second production step, conducting a nitrifying diffusion on the valve-closing element, the nitrifying diffusion including diffusing nitrogen into the base body material of the valve-closing element by providing a nitrogen-containing substance in at least one of: a gaseous state, a liquid state, or a plasma state; and
in a third production step, conducting a boronizing diffusion on the valve-closing element, the boronizing diffusion including diffusing boron into the base body material of the valve-closing element by providing a boron-containing substance in at least one of: a gaseous state, a liquid state, or a plasma state.

2. The method as recited in claim 1 , further comprising:
in a fourth production step, coating the valve-closing element with a coating material so that a layer made of the coating material is formed in a surface region of the valve-closing element.

3. The method as recited in claim 2 , wherein the layer made of the coating material is an amorphous carbon layer.

4. The method as recited in claim 2 , wherein the layer has a coating thickness between 0 and 50 micrometers.

5. The method as recited in claim 1 , wherein in the second production step, the valve-closing element is nitrified in such a way that a nitrification depth amounts to between 1 and 100 micrometers.

6. The method as recited in claim 1 , wherein in the second production step, the valve-closing element is nitrified in such a way that a nitrification depth amounts to between 5 and 50 micrometers.

7. The method as recited in claim 1 , wherein in the second production step, the valve-closing element is nitrified in such a way that a nitrification depth amounts to between 10 and 20 micrometers.

8. The method as recited in claim 1 , further comprising:
in a fourth production step, conducting a kolsterization diffusion on the valve-closing element.

9. The method as recited in claim 1 , further comprising:
developing a valve seat having a valve-seat surface;
developing a valve needle; and
mounting the valve-closing element on an end of the valve needle facing the valve seat, the valve-closing element being able to be moved between an open position and a closed position, the valve-closing element forming a sealing seat together with the valve-seat surface in the closed position;
wherein the valve-closing element has at least one of: i) a greater core hardness than the valve-seat surface, or ii) a greater surface hardness than the valve-seat surface.

10. The method as recited in claim 9 , wherein the valve-closing element has a surface region and in the closed position, the valve-closing element is in contact with the valve-seat surface in the surface region, the valve-closing element having a greater surface hardness in the surface region than the valve-seat surface.

11. The method as recited in claim 1 , further comprising:
developing a valve seat having a valve-seat surface;
developing a valve needle; and
mounting the valve-closing element on an end of the valve needle facing the valve seat;
wherein the valve-closing element has at least one of: a greater core hardness than the valve-seat surface, or a greater surface hardness than the valve-seat surface.

12. The method as recited in claim 1 , wherein the nitrifying diffusion provides the nitrogen-containing substance in a gaseous state.

13. The method as recited in claim 1 , wherein the nitrifying diffusion provides the nitrogen-containing substance in a liquid state.

14. The method as recited in claim 1 , wherein the nitrifying diffusion provides the nitrogen-containing substance in a plasma state.

Assignees

• Bosch Gmbh Robert

Inventors

• Mutlu Fatima

Classifications

• F02M2200/9061

  Special treatments for modifying the properties of metals used for fuel injection apparatus, e.g. modifying mechanical or electromagnetic properties · CPC title

• F02M2200/9038

  Coatings · CPC title

• F02M2200/02

  Fuel-injection apparatus having means for reducing wear · CPC title

• F02M61/1893

  Details of valve member ends not covered by groups F02M61/1866 - F02M61/188 · CPC title

• F02M61/18

  Injection nozzles, e.g. having valve seats; {Details of valve member seated ends, not otherwise provided for} · CPC title