Device and Method for Measuring the Geometry of a Workpiece

• US 20100288016A1
• Filed: 07/23/2010
• Published: 11/18/2010
• Est. Priority Date: 01/25/2008
• Status: Active Grant

• Current Assignee: Marposs GmbH (Sidco SA)
• Original Assignee: Marposs GmbH (Sidco SA)
• Inventors: Basar, Ivan
• Granted Patent: US 8,464,575 B2
• Time in Patent Office: Days
• US Class Current: 73/29.02
• CPC Class Codes: G01B 13/02 for measuring length, width or thickness G01B13/08 takes precedence

Abstract

In order to improve a device for measuring the geometry of a workpiece in such a way that the geometrical measurements are particularly precise wherein the device comprises a housing having a flow channel in which there is arranged a reference nozzle for the passage of a test fluid therethrough and a first pressure measuring device for measuring a first pressure of the test fluid upstream of the reference nozzle and also a second pressure measuring device for measuring a second pressure of the test fluid downstream of the reference nozzle, it is proposed that the device should comprise a differential pressure measuring device for measuring the differential pressure of the test fluid across the reference nozzle.

Claims

1. A device for measuring the geometry of a workpiece comprising a housing having a flow channel in which there is arranged a reference nozzle for the passage of a test fluid therethrough, a first pressure measuring device for measuring a first pressure of the test fluid upstream of the reference nozzle and a second pressure measuring device for measuring a second pressure of the test fluid downstream of the reference nozzle, wherein a differential pressure measuring device for measuring the differential pressure of the test fluid across the reference nozzle is provided.

2. A device in accordance with claim 1, wherein the differential pressure measuring device is connected in fluidic manner to the flow channel upstream and downstream of the reference nozzle.

3. A device in accordance with claim 1, wherein the differential pressure measuring device is configured in the form of a differential pressure sensor.

4. A device in accordance with claim 1, wherein the differential pressure measuring device is arranged on or in the housing.

5. A device in accordance with claim 1, wherein a moisture measuring device for measuring the moisture content of the test fluid is provided.

6. A device in accordance with claim 5, wherein the moisture measuring device has a moisture measuring surface which is connected in fluidic manner to the flow channel.

9. A device in accordance with claim 1, wherein a temperature measuring device for measuring the temperature of the test fluid is provided.

10. A device in accordance with claim 9, wherein the temperature measuring device has a temperature measuring surface which is connected in fluidic manner to the flow channel.

12. A device in accordance with claim 9, wherein the temperature measuring device is arranged on or in the housing.

13. A device in accordance with claim 1, wherein an ambient temperature measuring device for measuring the ambient temperature of the device is provided.

14. A device in accordance with claim 13, wherein the ambient temperature measuring device has a temperature measuring surface which is connected in fluidic manner to the environment of the device.

16. A device in accordance with claim 1, wherein the ambient temperature measuring device is configured in the form of a temperature sensor.

18. A device in accordance with claim 1, wherein an evaluating unit for evaluating the signals of at least one measuring devices is provided.

19. A device in accordance with claim 1, wherein a measurement nozzle through which the test fluid is arranged to flow is provided.

7-8. -8. (canceled)

11. (canceled)

15. (canceled)

17. (canceled)

20. A method for measuring the geometry of a workpiece, wherein a test fluid is arranged to flow through a reference nozzle located in a flow channel of a housing, wherein a first pressure of the test fluid is measured upstream of the reference nozzle and wherein a second pressure of the test fluid is measured downstream of the reference nozzle, wherein, in addition to the first pressure of the test fluid and the second pressure of the test fluid, the differential pressure of the test fluid across the reference nozzle is measured and/or in that the moisture content of the test fluid is measured.

21. A method in accordance with claim 20, wherein there is determined a deviation between a measured differential pressure of the test fluid and the difference between a first measured pressure of the test fluid and a second measured pressure of the test fluid.

22. A method in accordance with claim 21, wherein the deviation is compared with a limit value.

23. A method in accordance with claim 22, wherein the limit value is adjustable.

24. A method in accordance with claim 21, wherein a quantity of test fluid is determined using the first measured pressure of the test fluid and/or the second measured pressure of the test fluid and in that a dimension of the workpiece is determined using the thus determined quantity of test fluid.

26. A method in accordance with claim 24, wherein the quantity of test fluid is determined using the measured moisture content of the test fluid.

27. A method in accordance with claim 24, wherein the temperature of the test fluid is measured and in that the quantity of test fluid is determined using the measured temperature of the test fluid.

28. A method accordance with claim 24, wherein an ambient temperature is measured and in that the dimension of the workpiece is determined using the measured ambient temperature.

25. (canceled)

29. (canceled)

30. A device for measuring the geometry of a workpiece comprising a housing having a flow channel in which there is arranged a reference nozzle for the passage of a test fluid therethrough, a first pressure measuring device for measuring a first pressure of the test fluid upstream of the reference nozzle and a second pressure measuring device for measuring a second pressure of the test fluid downstream of the reference nozzle, wherein a moisture measuring device for measuring the moisture content of the test fluid is provided.

31. A device in accordance with claim 30, wherein the moisture measuring device is configured in the form of a humidity sensor.

32. A device in accordance with claim 30, wherein the moisture measuring device is arranged on or in the housing.