Sealing arrangement for a piezo actuator of a fuel injector
View Patent ↗A seal ( 10 ) for a piezo-actuator of a fuel injector with terminal posts ( 12 ) projecting out of the piezo-actuator and a head arrangement ( 14 ) mounted on the piezo-actuator with openings ( 16 ) for passage of the terminal posts ( 12 ) is particularly suitable even for comparatively thin head plates. A sealing unit ( 18 ) mounted on the head arrangement ( 14 ) and provided with openings for passage of the terminal posts ( 12 ) is provided, having a support ( 22 ), on which a sealing material ( 26 ) is arranged, which is in contact in a sealing manner with the peripheral surfaces of the terminal posts ( 12 ) and a peripheral region of the head arrangement ( 14 ) and in which an element ( 20 ) made of microporous material is integrated to create gas permeability.
1. A sealing arrangement for sealing a piezo-actuator of a fuel injector in an internal combustion engine comprising:
terminal posts projecting out of the piezo-actuator,
a head arrangement mounted on the piezo-actuator comprising openings for passage of the terminal posts, and
a sealing unit mounted on the head arrangement comprising openings for passage of the terminal posts, wherein the sealing head comprises a support on which a sealing material is arranged which is in contact in a sealing manner with the peripheral surfaces of the terminal posts and with a peripheral region of the head arrangement and in which an element made of a microporous material is integrated to create gas permeability.
2. The sealing arrangement according to claim 1 , wherein the support is made of plastic.
3. The sealing arrangement according to claim 1 , wherein the sealing material is an elastomer.
4. The sealing arrangement according to claim 1 , wherein the sealing material is configured as a molding around the support.
5. The sealing arrangement according to claim 1 , wherein the sealing material is produced as a component in a twin-component injection molding method.
6. The sealing arrangement according to claim 1 , wherein a close connection is created by vulcanization between the material of the support and the sealing material.
7. The sealing arrangement according to claim 1 , wherein the sealing material is compressed towards the support.
8. The sealing arrangement according to claim 1 , wherein the element made from the microporous material is welded to the support.
9. The sealing arrangement according to claim 1 , wherein the microporous material is made of ePTFE.
10. The sealing arrangement according to claim 1 , wherein the element made of microporous material is essentially disk-shaped.
11. A method for sealing a piezo-actuator of a fuel injector in an internal combustion engine wherein the piezo-actuator comprises terminal posts projecting out of the piezo-actuator, a head arrangement mounted on the piezo-actuator comprising openings for passage of the terminal posts, the method comprising the steps of:
mounting a sealing unit on the head arrangement comprising openings for passage of the terminal posts, wherein the sealing head comprises a support;
arranging a sealing material on the support which is in contact in a sealing manner with the peripheral surfaces of the terminal posts and with a peripheral region of the head arrangement, and
integrating an element made of a microporous material into the sealing material to create gas permeability.
12. The method according to claim 11 , wherein the support is made of plastic.
13. The method according to claim 11 , wherein the sealing material is an elastomer.
14. The method according to claim 11 , wherein the sealing material is configured as a molding around the support.
15. The method according to claim 11 , wherein the sealing material is produced as a component in a twin-component injection molding method.
16. The method according to claim 11 , further comprising the step of creating a close connection by vulcanization between the material of the support and the sealing material.
17. The method according to claim 11 , wherein the sealing material is compressed towards the support.
18. The method according to claim 11 , wherein the element made from the microporous material is welded to the support.
19. The method according to claim 11 , wherein the microporous material is made of ePTFE.
20. The method according to claim 11 , wherein the element made of microporous material is essentially disk-shaped.