Spark plug housing including an electroplated or a chemically applied nickel-containing protective layer and a silicon-containing sealing layer, and a spark plug including this housing, and method for manufacturing this housing

Patent metadata

Field	Value
Publication number	US-11245251-B2
Application number	US-201917257853-A
Country	US
Kind code	B2
Filing date	May 31, 2019
Priority date	Jul 9, 2018
Publication date	Feb 8, 2022
Grant date	Feb 8, 2022

Abstract

A housing for a spark plug. The housing includes a bore along the longitudinal axis X of the housing, as the result of which the housing has an outer side and an inner side, and an electroplated or chemically applied nickel-containing protective layer situated on at least one portion of the outer side of the housing and a sealing layer situated on the nickel-containing protective layer. The sealing layer contains silicon. A first intermediate layer is applied between the housing and the nickel-containing protective layer and/or a second intermediate layer is applied between the nickel-containing protective layer and the sealing layer and/or a cover layer is applied on the sealing layer. The sealing layer may be free of chromium.

First claim

What is claimed is:

1. A spark plug, comprising:
a housing including a bore along a longitudinal axis of the housing, as a result of which the housing has an outer side and an inner side, an electroplated or chemically applied nickel-containing protective layer situated on at least one portion of the outer side of the housing, and a sealing layer situated on the nickel-containing protective layer, wherein the sealing layer contains silicon;
an insulator situated in the housing;
a center electrode situated in the insulator; and
a ground electrode situated at the combustion chamber-side end of the housing, the ground electrode and the center electrode being configured for jointly forming a spark gap,
wherein the sealing layer contains silicon, wherein the sealing layer is made by silanization of a surface of the housing, which is covered by the nickel-containing protective layer.

2. A housing for a spark plug, comprising:
a bore along a longitudinal axis of the housing, as a result of which the housing has an outer side and an inner side;
an electroplated or chemically applied nickel-containing protective layer situated on at least one portion of the outer side of the housing; and
a sealing layer situated on the nickel-containing protective layer, wherein the sealing layer contains silicon,
wherein the sealing layer contains silicon, wherein the sealing layer is made by silanization of a surface of the housing, which is covered by the nickel-containing protective layer.

3. The housing as recited in claim 2 , wherein the sealing layer is free of chromium.

4. The housing as recited in claim 2 , wherein at least one of: (i) a first intermediate layer is situated between the housing and the nickel-containing protective layer, (ii) a second intermediate layer is situated between the nickel-containing protective layer and the sealing layer, or (iii) a cover layer is situated on the sealing layer.

5. The housing as recited in claim 4 , wherein at least one of the first intermediate layer has a layer thickness of 1 nm to 1000 nm, (ii) the second intermediate layer has a layer thickness of 1 nm to 1000 nm, or (iii) the cover layer has a layer thickness of 1 nm to 2000 nm.

6. The housing as recited in claim 4 , wherein the nickel-containing protective layer and the sealing layer, and at least one of: (i) the first intermediate layer, (ii) the second intermediate layer, or (iii) the cover layer, are formed on an entire outer side of the housing and on at least one portion of the inner side of the housing.

7. The housing as recited in claim 2 , wherein the sealing layer has a layer thickness of 10 nm to 10 μm.

8. The housing as recited in claim 2 , wherein the sealing layer has a layer thickness of 100 nm to 1 μm.

9. The housing as recited in claim 2 , wherein the nickel-containing protective layer has a layer thickness of 1 μm to 30 μm on the housing.

10. A method for manufacturing a housing, comprising the following steps:
providing a housing for a spark plug including a nickel-containing protective layer, which was applied onto the housing using an electroplating coating method or a chemical coating method;
after the providing, rinsing the housing coated with the nickel-containing protective layer; and
after the rinsing, applying a sealing layer onto the nickel-containing protective layer,
wherein the sealing layer contains silicon, wherein the sealing layer is made by silanization of a surface of the housing, which is covered by the nickel-containing protective layer.

11. The method as recited in claim 10 , wherein the housing includes an intermediate layer suited on the nickel-containing protective layer, wherein in the applying step, the sealing layer is applied onto the intermediate layer.

12. The method as recited in claim 10 , further comprising:
before the rinsing step, cleaning the surface of the housing coated with the nickel-containing protective layer.

13. The method as recited in claim 10 , further comprising:
after the applying of the sealing layer onto the nickel-containing protective layer, drying the housing to remove possible water or solvent from the application of the sealing layer from the surface of the housing.

14. The method as recited in claim 13 , wherein after the drying step, a polycondensation step occurs, in which the sealing layer cures.

15. The method as recited in claim 10 , further comprising:
applying a cover layer onto the sealing layer.

16. The method as recited in claim 10 , wherein a sol-gel process, or CCVD, or PVD is utilized as a coating method for the applying of the sealing layer.

17. The method as recited in claim 10 , wherein silanes with functionalization including alkoxysilanes, or aminosilanes, or acrylsilanes, are utilized for the sealing layer.

18. The method as recited in claim 17 , wherein, additionally, silanes without functionalization, including alkyl trialkoxysilanes, are also utilized for the sealing layer.

Assignees

• Bosch Gmbh Robert

Inventors

• Stahl Juergen
• Hackenberg Juergen
• Hippchen Silvan
• Hirte Tina

Classifications

• H01T13/06 Primary

  Covers forming a part of the plug and protecting it against adverse environment · CPC title

• H01T13/20 Primary

  characterised by features of the electrodes or insulation · CPC title

• C25D9/06

  by anodic processes · CPC title

• C23C16/401

  containing silicon · CPC title

• C23C18/32

  Coating with nickel, cobalt or mixtures thereof with phosphorus or boron (C23C18/50 takes precedence) · CPC title