VALVE

Abstract

A valve having a housing, a solenoid arranged in the housing, a pin movable by the solenoid, a cup-shaped piston connected to the pin, a seal arranged in the base region of the piston that interacts with a valve seat, and a seal arranged in the region of the open end of the piston and seals the piston from the housing. The seal interacting with the valve seat has an outer diameter, which approximately corresponds to the outer diameter of the seal at the open end of the piston.

Claims

1.-10. (canceled)

11. A valve comprising: a housing; a valve seat; a solenoid arranged in the housing; a pin configured to be moved by the solenoid; a cup-shaped piston connected to the pin; a first seal arranged in a base region of the cup-shaped piston that interacts with the valve seat; and a second seal or a stop in a region of an open end of the cup-shaped piston, wherein the first seal interacting with the valve seat has an outer diameter that substantially corresponds to an outer diameter of the second seal or stop at the open end of the cup-shaped piston.

12. The valve as claimed in claim 11, wherein the outer diameters of the first seal and the second seal or stop differ by maximum 5%.

13. The valve as claimed in claim 11, wherein the first seal and the second seal or stop are composed of a rubber.

14. The valve as claimed in claim 13, wherein the rubber is vulcanized on.

15. The valve as claimed in claim 11, wherein the first seal interacting with the valve seat and the second seal or stop at the open end of the cup-shaped piston are separate components.

16. The valve as claimed in claim 11, wherein the first seal interacting with the valve seat and the second seal or stop at the open end of the cup-shaped piston are formed integrally.

17. The valve as claimed in claim 13, wherein the first seal interacting with the valve seat and the second seal or stop at the open end of the cup-shaped piston are mounted as a cover on the cup-shaped piston.

18. The valve as claimed in claim 11, wherein the outer diameter of the first seal has an axial height of 10% to 50% of a height of the cup-shaped piston.

19. The valve as claimed in at least one of claim 16, wherein the outer diameter of the first seal becomes smaller in a direction of the open end of the cup-shaped piston.

20. The valve as claimed in claim 11, wherein a thickness of the second seal or stop at the open end of the cup-shaped piston is one of: 0.4 mm to 1 mm and 0.5 mm to 0.8 mm.

21. The valve as claimed in claim 13, wherein the rubber is a fluoro rubber.

22. The valve as claimed in claim 16, wherein the first seal interacting with the valve seat and the second seal or stop at the open end of the cup-shaped piston are mounted as a cover on the cup-shaped piston.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The invention will be described in more detail on the basis of an exemplary embodiment. In the figures:

[0023] FIG. 1 is a sectional illustration of a valve according to the prior art;

[0024] FIG. 2 is an enlarged sectional illustration of the valve according to the invention in the region of the piston; and

[0025] FIG. 3 is an enlarged sectional illustration of a piston.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS

[0026] FIG. 1 shows the valve, which comprises a housing 1. The housing 1 has an integrally formed flange 3, via which the housing 1 is flanged-mounted on a turbocharger (not illustrated) in a region of the bypass line 4. In the housing 1, there is a solenoid 5 with a coil 6 and a metal pin 7. The metal pin 7 is connected to a cup-shaped piston 8 that has a seal 10 at the periphery of its base 9. In the closed position shown, the seal 10 bears against the valve seat 11 in order to close off the bypass line 4, so that no medium can flow from the line 4 into the line 12. Here, a spring 7a pushes the piston 8 in the direction of the valve seat 11. A further seal 13 with a sealing lip 14 is arranged at the open end of the piston 8. If the solenoid 5 is electrically energized, a magnetic force acts on the armature 2, whereby the piston 8 is moved in the direction of the housing 1. Here, the sealing lip 14 seals off the piston 8 against the housing 1.

[0027] In FIG. 2, the metallic piston 8 also has a stop 13 at the open end of the piston 8, and a seal 10 in the base region of the piston 8. The stop 13 extends at an angle of 45 towards the radial outside and in the direction of the solenoid 5 and has a thickness of 0.8 mm. In the closing direction of the valve, the stop 13 meets a housing part 15 where it seals the piston 8 against the housing 1. On the radial inside, the stop 13 has a cylindrical stop face 16 which, on movement of the piston into the open position, cooperates with a correspondingly formed face of the housing 1 and thus limits the further movement of the piston 8.

[0028] The seal 10 and stop 13 are produced integrally from fluoro rubber, wherein this component is mounted on the piston 8 as a cover. The seal 10 has an outer diameter which corresponds approximately to the outer diameter of the stop 13 or is slightly smaller. A resulting force is negligible in relation to the magnetic force produced by the solenoid. The outer diameter of the seal 10 is constant over an axial height of 40% of the piston height. In the further axial course, the outer diameter of the cover reduces in the form of a chamfer 17 to approximately 1 mm. With this thickness, the cover transforms into the stop 13 at the open end of the piston 8.

[0029] The piston 8 in FIG. 3 consists of plastic with a covering of elastomer which forms the stop 13 and the seal 10. The piston 8 corresponds in basic structure to the piston of FIG. 2. The difference is that the elastomer covering has an almost constant thickness. The increase in outer diameter in the region of the seal 10 is achieved by a correspondingly greater wall thickness of the plastic piston 8 in this region.

[0030] Thus, while there have shown and described and pointed out fundamental novel features of the invention as applied to a preferred embodiment thereof, it will be understood that various omissions and substitutions and changes in the form and details of the devices illustrated, and in their operation, may be made by those skilled in the art without departing from the spirit of the invention. For example, it is expressly intended that all combinations of those elements and/or method steps which perform substantially the same function in substantially the same way to achieve the same results are within the scope of the invention. Moreover, it should be recognized that structures and/or elements and/or method steps shown and/or described in connection with any disclosed form or embodiment of the invention may be incorporated in any other disclosed or described or suggested form or embodiment as a general matter of design choice. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto.