Electrically conductive plastic electrode sealingly embedded in an insulating plastic valve seat

• US 7,122,101 B2
• Filed: 01/28/2003
• Issued: 10/17/2006
• Est. Priority Date: 07/28/2000
• Status: Expired due to Fees

• Current Assignee: Xomox International GmbH & Co. (Crane Company)
• Original Assignee: Xomox International GmbH & Co. (Crane Company)
• Inventors: Gonsior, Wolfgang
• Primary Examiner(s): Bell, Bruce F.
• Application Number:
  US10/352,180
• Publication Number:
  US 20030221494A1
• Time in Patent Office: 1,358 Days
• Field of Search: 204/280, 204/286.1, 204/287, 204/297.01, 204/404
• US Class Current: 204/280
• CPC Class Codes: G01N 27/07 Construction of measuring vessels; Electrodes therefor

Abstract

A sensor including at least one electrode (3, 4) which is made of electrically conductive plastic and is connected to one end of an electrical conductor (5, 6). The electrode (3, 4) and conductor (5, 6) are surrounded by an insulating housing (2, 22), except that the electrode has an exposed surface (7, 8) for contacting an aggressive or corrosive medium inside the housing. The other end (11, 12) of the electrical conductor protrudes from the housing (2, 22). The housing (2, 22) is made of an electrically insulating plastic material which is joined to the electrode (3, 4) in a sealed manner. In a preferred embodiment, the housing (2, 22) forms a valve seat and seal for a bottom drain valve of a fluid container.

Claims

1. An apparatus comprising at least one electrically conductive plastic electrode substantially embedded in a surrounding insulating housing and connected to a first end of an electrical conductor also embedded within the insulating housing and extending out of said housing to an exposed second end;

said electrode having an exposed surface for contacting a medium in said housing;

said housing surrounding said electrode being comprised of insulating plastic tightly bonded to said electrode;

wherein

said electrical conductor is constructed as a support for said electrode or an electrode support is associated with the electrical conductor, and

said housing comprises a radial flange through which the electrical conductor is extended such that said second end of the conductor emerges from a radially outer surface of the flange.

2. An apparatus according to claim 1, wherein said flange is an annular flange with a cylindrical outer surface.

3. An apparatus according to claim 1, wherein the medium in said housing is a corrosive liquid.

4. An apparatus according to claim 1, wherein said housing is made entirely of insulating plastic material.

5. An apparatus according to claim 1, wherein the conductive electrode is comprised of a normally insulating, fluid-impermeable plastic material containing conductive particles distributed throughout.

6. An apparatus according to claim 1, wherein the plastic of the electrode is a fluorine-containing synthetic resin material.

7. An apparatus according to claim 1, wherein the plastic of the housing is a fluorine-containing synthetic resin material.

8. An apparatus according to claim 1, wherein the electrode and the electrical conductor are integrated into the housing during manufacture of the housing, whereby a sealed joint is formed between the plastic of the electrode and the plastic of the housing.

9. An apparatus according to claim 1, wherein the bond between the electrode and the housing is fluid-tight or pressure-tight.

10. An apparatus according to claim 1, wherein said housing is a valve seat for a valve.

11. An apparatus according to claim 10, wherein the exposed surface of the electrode is positioned in an annular surface of the valve seat.

12. An apparatus according to claim 1, wherein the electrical conductor is provided with perforations in the vicinity of the electrode, which are filled by the plastic of the electrode.

13. An apparatus according to claim 1, wherein the electrical conductor is made of metal or electrically conductive plastic, and the electrical conductor and the electrode together form an integral or one-piece unit.

14. An apparatus according to claim 1, wherein the electrical conductor is mounted in a support element made of an electrically insulating plastic.

15. An apparatus according to claim 1, wherein the electrical conductor is supported by a support body having a higher rigidity or strength than the plastic of the housing.

16. An apparatus according to claim 1, wherein the electrode, except for the exposed surface for contacting the medium in the housing, is enclosed around its entire outer contour by the electrically non-conductive plastic of the housing.

17. An apparatus according to claim 1, wherein the conductive plastic of electrode is bonded sealingly to the insulating plastic of the housing by fusion or welding.

18. An apparatus according to claim 1, wherein the exposed surface of the electrode lies essentially in the same plane as a surface of the housing.

19. An apparatus according to claim 18, wherein said surface of the housing is an axial end face of a tubular housing.

20. An apparatus according to claim 1, wherein said apparatus is an electrical sensor.