Gas exchange valve of an internal combustion engine

Patent metadata

Field	Value
Publication number	US-9611766-B2
Application number	US-201414301779-A
Country	US
Kind code	B2
Filing date	Jun 11, 2014
Priority date	Jun 11, 2013
Publication date	Apr 4, 2017
Grant date	Apr 4, 2017

Abstract

A gas exchange valve of an internal combustion engine may include a hollow valve stem and a valve disc. The valve disc may include a valve bottom and a hollow valve cone which is connected to an outer edge of said valve bottom. The hollow valve cone may taper with increasing distance from the valve bottom. The valve stem may pass through the hollow valve cone. The valve stem may be fixedly connected on the one hand to the valve bottom and on the other hand to the tapered end of the valve cone. The valve stem may include a first hollow space which is fluidically separated from a second hollow space arranged in the valve disc. The first hollow space and the second hollow space may have a different cooling agent filling level.

First claim

The invention claimed is:

1. A gas exchange valve of an internal combustion engine, comprising:
a hollow valve stem having a longitudinal axis and a valve disc,
the valve disc includes a valve bottom and a hollow valve cone, the valve cone connected to an outer edge of said valve bottom, wherein the hollow valve cone tapers with increasing distance from the valve bottom, and
the valve stem passes through the hollow valve cone, wherein the valve stem is fixedly connected at an end face to the valve bottom to define a fluid-tight connection and in a region axially spaced from the end face to the tapered end of the valve cone,
wherein the valve stem includes a first hollow space, which is fluidically separated and radially inward from a second hollow space arranged in the valve disc via the fluid-tight connection between the end face of the valve stem and the valve bottom,
wherein the first hollow space radially inward of the fluid-tight connection has a higher cooling agent filling level than the second hollow space, thereby causing a shaker effect in the first and second hollow spaces to enhance cooling, and
wherein at least one of the valve disc and the valve stem has a nitriding layer.

2. The gas exchange valve according to claim 1 , wherein at least one hollow space includes a cooling agent filled therein.

3. The gas exchange valve according to claim 2 , wherein the cooling agent comprises sodium.

4. The gas exchange valve according to claim 1 , wherein the valve stem has the nitriding layer.

5. The gas exchange valve according to claim 1 , wherein the nitriding layer is between 1-20 μm thick.

6. The gas exchange valve according to claim 1 , wherein the valve cone includes a wall thickness of 1.0 mm or less.

7. The gas exchange valve according to claim 1 , wherein the first hollow space includes an inner diameter at least ⅔ of an outer diameter of the valve stem.

8. The gas exchange valve according to claim 1 , wherein the gas exchange valve includes at least one of a 601H-steel, an 800H-steel, a 286-steel and a 602H-steel.

9. The gas exchange valve according to claim 1 , wherein the valve stem at the connection to the valve bottom has a larger diameter than at the connection to the valve cone.

10. The gas exchange valve according to claim 1 , wherein the nitriding layer is a superficial nitrided layer and an underlying material of the valve disc is steel.

11. The gas exchange valve according to claim 7 , wherein the valve stem defines a first diameter at the connection with the valve bottom and a second diameter at the connection with the valve cone, wherein the first diameter is larger than the second diameter.

12. An internal combustion engine, comprising: at least one cylinder and at least one associated gas exchange valve, the gas exchange valve including:
a valve disc including a valve bottom and a hollow valve cone coupled to an outer periphery of the valve bottom, the valve cone tapering with increasing distance from the valve bottom to define an opening;
a hollow valve stem extending through the opening of the valve cone, the valve stem fixedly coupled to the valve bottom and the valve cone, wherein the valve stem is connected to the valve bottom on an end face adjoining the valve bottom to form a fluid-tight connection, the valve stem defining a first hollow space fluidically separated and radially inward from a second hollow space arranged in the valve disc;
wherein the first hollow space radially inward of the fluid-tight connection has a higher cooling agent filling level than the second hollow space; and
wherein at least the valve bottom of the valve disc is composed of a steel material, and wherein the valve bottom includes a superficial nitrided layer.

13. The internal combustion engine according to claim 12 , wherein at least one hollow space includes a cooling agent filled therein.

14. The internal combustion engine according to claim 12 , wherein at least one of the valve cone further includes the superficial nitrided layer and the valve stem further includes the superficial nitrided layer.

15. The internal combustion engine according to claim 12 , wherein the superficial nitrided layer has a thickness between 1-20 μm.

16. The internal combustion engine according to claim 12 , wherein the valve cone includes a thickness of 1.0 mm or less.

17. The internal combustion engine according to claim 12 , wherein the first hollow space includes an inner diameter of at least ⅔ an outer diameter of the valve stem.

18. The internal combustion engine according to claim 12 , wherein the valve stem defines a first diameter at the coupling with the valve bottom and a second diameter at the coupling with the valve cone, wherein the first diameter is larger than the second diameter.

19. The gas exchange valve according to claim 11 , wherein the valve cone includes a wall thickness of 1.0 mm or less.

20. A gas exchange valve for an internal combustion engine, comprising:
a valve disc including a valve bottom and a hollow valve cone coupled to an outer periphery of the valve bottom, the valve cone tapering with increasing distance from the valve bottom to define an opening;
a hollow valve stem extending through the opening of the valve cone, the valve stem fixedly connected to the valve bottom and the valve cone, wherein the valve stem is connected to the valve bottom on an end face adjoining the valve bottom to form a fluid-tight connection, the valve stem including a first diameter at the connection with the valve bottom and a second diameter at the connection with the valve cone, wherein the first diameter is larger than the second diameter;
wherein the valve stem defines a first hollow space fluidically separated and radially inward from a second hollow space arranged in the valve disc, the first hollow space radially inward of the fluid-tight connection having a higher cooling agent filling level than the second hollow space; and
wherein at least the valve bottom includes a superficial nitrided layer having a hardness greater than that of an underlying material of the valve bottom.

Assignees

• Mahle Int Gmbh

Inventors

• Kroos Peter
• Luven Christoph
• Mueller Alexander
• Puck Alexander

Classifications

• F01L3/14

  by means of a liquid or solid coolant, e.g. sodium, in a closed chamber in a valve · CPC title

• F01L3/20 Primary

  Shapes or constructions of valve members, not provided for in preceding subgroups of this group · CPC title

• F01L3/00

  Lift-valve, i.e. cut-off apparatus with closure members having at least a component of their opening and closing motion perpendicular to the closing faces; Parts or accessories thereof · CPC title