Apparatus for determining a physical variable of a liquid or solid medium

• US 6,435,025 B1
• Filed: 08/14/2000
• Issued: 08/20/2002
• Est. Priority Date: 09/07/1999
• Status: Expired due to Fees

• Current Assignee: Endress+Hauser GmbH+Co (ENDRESS)
• Original Assignee: Endress+Hauser GmbH+Co (ENDRESS)
• Inventors: Krause, Michael
• Primary Examiner(s): Williams, Hezron
• Assistant Examiner(s): WILSON, KATINA M
• Application Number:
  US09/638,421
• Time in Patent Office: 736 Days
• Field of Search: 732/90.R, 733/04.R, 73/530.1, 73/530.6, 73/530.7, 73/540.1, 733/04.C
• US Class Current: 73/304.00C
• CPC Class Codes: G01F 23/268 mounting arrangements of probes
• CPC Class Codes: G01N 2291/02836 Flow rate, liquid level

Abstract

The object of the present invention is to propose an apparatus for determining a physical variable of a medium (2) in which the formation of deposits or buildups of the medium (2) on a subelement (4) of the apparatus (1) which comes into contact with the medium (2) is reduced or avoided.

For this purpose, at least the subelement (4) is provided with a microstructured surface layer (7).

Claims

1. An apparatus for determining a physical variable of a liquid or solid medium in a container or in a vessel, comprising a plurality of subelements, at least one subelemnet coming indirectly or directly into contact with the liquid or solid medium, and the at least one subelment having a microstructured surface layer, the microstructured surface layer having elevations and depressions, the distance between the elevations lying in the range from 5 to 200 μ

m and the height of the elevations lying in the range from 5 to 100 μ

m.

2. The apparatus as claimed in claim 1, the surface layer being a layer of varnish or paint which has been applied to the at lease one subelment.

3. The apparatus as claimed in claim 2, the plurality of subelements being configured to determine at least the pressure, temperature, humidity or throughflow or mass throughflow of the medium.

4. The apparatus as claimed in claim 1, the physical variable being a filling level of a product in the container.

5. The apparatus as claimed in claim 4, the at least one subelement being the probe part of a capacitive sensor which comes into contact with the product for the purpose of level measurement.

6. The apparatus as claimed in claim 4, the subelement being vibration rods of a vibration sensor.

7. The apparatus as claimed in claim 4, the subelement being an antenna which transmits sound, ultrasound or electromagnetic waves in a direction of a surface of the medium, or the subelement being a waveguide which guides the electromagnetic waves in a direction of a surface of the product or introduces them into the product.

8. The apparatus as claimed in claim 1, the physical variable being the pressure, temperature, humidity or throughflow or mass throughflow of the medium.

9. The apparatus as claimed in claim 1, the plurality of subelements being configured to determine at least a filling level of a product in the container.

10. The apparatus as claimed in claim 2, the plurality of subelements being configured to determine at least a filling level of a product in the container.

11. The apparatus as claimed in claim 1, the plurality of subelements being configured to determine at least the pressure, temperature, humidity or throughflow or mass throughflow of the medium.