Apparatus for measuring the condition of a felt in a paper machine

• US 5,349,845 A
• Filed: 03/31/1993
• Issued: 09/27/1994
• Est. Priority Date: 04/07/1992
• Status: Expired due to Fees

• Current Assignee: Tamfelt Oy AB (Valmet Oyj)
• Original Assignee: Tamfelt Oy AB (Valmet Oyj)
• Inventors: Blom, Mikko
• Primary Examiner(s): Williams, Hezron E.
• Assistant Examiner(s): Brock, Michael J.
• Application Number:
  US08/041,063
• Time in Patent Office: 545 Days
• Field of Search: 73/37.7, 73/37.8, 73/38, 73/866, 73/73, 34/30, 34/48, 34/31, 162/263, 324/642, 324/643, 324/644, 374/135, 374/137, 374/143
• US Class Current: 73/38
• CPC Class Codes: D21F 1/32 Washing wire-cloths or felts

Abstract

The invention relates to a measuring apparatus for measuring the condition of a felt in a paper machine, comprising a measuring head (1) connected to a vacuum source. Air is sucked into the measuring head through the felt, and the air and the water carried with the air are removed through separate conduits. The measuring head comprises a microwave head for measuring the water content of the felt, and a temperature detector for measuring the temperature of the sucked air concurrently with the vacuum measurement.

Claims

1. Apparatus for measuring the condition of a felt in a paper machine, comprising a measuring head arranged to be positioned against the surface of the felt, an air conduit being connected to the measuring head for sucking air through the felt into the measuring head by utilizing a vacuum, and a water removal conduit being connected to said measuring head for separately removing water carried with the air into the measuring head from the felt;

measuring means for measuring the vacuum created during measuring;

a microwave radiator connected to the measuring head for measuring the water content of the felt, and a temperature detector for measuring the temperature of the air sucked through the measuring head into the air conduit.

2. Measuring apparatus according to claim 1, wherein the microwave radiator is arranged to measure the water content of the felt concurrently with the vacuum measurement.

3. Measuring apparatus according to claim 1, wherein the temperature detector is arranged to measure the air temperature continuously during the vacuum measurement.

4. Measuring apparatus according to claim 1, further comprising a display device for simultaneously displaying the measured value of each concurrent measurement in the form of a transverse profile of the felt.

5. Measuring apparatus according to claim 4, further comprising data preparation means for receiving said measured values and preparing said measured values for display by said display device in a predetermined format.

6. Measuring apparatus according to claim 5, wherein said data preparation means is a computer.

7. Measuring apparatus according to claim 1, wherein said temperature detector is a thermometer.

8. Measuring apparatus according to claim 1, wherein said microwave radiator is adapted for measuring the thickness of the felt.

9. Measuring apparatus according to claim 1, wherein said microwave radiator emits radiation at a frequency within a range of several to several thousand megahertz.

10. Measuring apparatus according to claim 1, wherein said measuring head includes a perforated sensor surface to facilitate said sucking of air through the felt and into the measuring head.

11. Measuring apparatus according to claim 10, wherein said measuring head further includes a separation plate mounted therein for separating water carried with the air into the measuring head.

12. Measuring apparatus according to claim 1, further comprising support means for adjustably supporting said measuring head.

13. Measuring apparatus according to claim 12, wherein said support means is adapted to facilitate the movement of said measuring head to one or more selected positions along a width of the felt.

14. Measuring apparatus according to claim 13, further comprising means for reconditioning said felt in accordance with said measurements.

15. Measuring apparatus according to claim 14, wherein said means for reconditioning is mounted to said support means.

16. Measuring apparatus according to claim 15, wherein said means for reconditioning is a needle jet head.