Patent US3891392A successfully refreshed from Google Patents.
← Back to Patent Explorer
US3891392A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of maintaining a column of liquid within an open-ended tube, and a tube device for carrying out the method

Assignee: Sterilin Ltd
•
Filing: 1973-01-24
•
Granted: 1975-06-24
•
Expires: 1993-01-24
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A method of and device for maintaining a column of liquid comprising comprises a straight open-ended tube, and a plug of porous material frictionally located within the bore of the tube at a predetermined distance from one end of the tube. A column of liquid may be maintained within such a tube by placing the said one end of the tube in communication with a supply of liquid, and applying suction to the other end of the tube to draw a column of liquid into the tube to a level above the plug. The suction is then removed to allow the column of liquid to fall until its surface contacts the plug, whereupon the remaining column of liquid is maintained by interaction of the respective physical characteristics of the liquid, the plug, and the tube.

Inventors

  • 👤 Peter Alan Betts
  • 👤 Kenneth Stephenson

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 14:18
CPC Classifications
B; B01; B01L; B01L3/00; B01L3/56; B01L3/561; B01L3/02; B01L3/021; B01L3/0213; Y; Y10; Y10T; Y10T436/00; Y10T436/25; Y10T436/2575

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 136 words
A METHOD OF MAINTAINING A COLUMN OF LIQUID WITHIN AN OPEN ENDED TUBE COMPRISING THE STEPS OF PLACING WITHIN THE TUBE A PLUG OF POROUS MATERIAL HAVING A CAPILLARY ATTRACTION FOR A LIQUID, POSITIONING THE PLUG AT A PREDETERMINED DISTANCE FROM ONE END OF THE TUBE CORRESPONDING TO THE HEIGHT OF THE DESIRED COLUMN OF LIQUID, PLACING THE ONE END OF THE TUBE IN COMMUNICATION WITH A SUPPLY OF LIQUID, APPLYING TO THE OTHER END OF THE TUBE SUCTION SUFFICIENT TO DRAW A COLUMN OF LIQUID FROM THE LIQUID SUPPLY UNTO THE TUBE TO A POSITION WHEREIN ITS SURFACE LEVEL LIES ABOVE THE PLUG, TERMINATING THE SUCTION TO LOWER THE COLUMN OF LIQUID UNTIL THE LIQUID SURFACE CONTACTS THE PLUG, AND MAINTAINING THE REMAINING COLUMN OF LIQUID BY CAPILLARY ATTRACTION BETWEEN THE LIQUID AND THE PLUG.
Claim 2
Independent Claim 136 words
A METHOD OF MAINTAINING A COLUMN OF LIQUID WITHIN AN OPEN ENDED TUBE COMPRISING THE STEPS OF PLACING WITHIN THE TUBE A PLUG OF POROUS MATERIAL HAVING A CAPILLARY ATTRACTION FOR A LIQUID, POSITIONING THE PLUG AT A PREDETERMINED DISTANCE FROM ONE END OF THE TUBE CORRESPONDING TO THE HEIGHT OF THE DESIRED COLUMN OF LIQUID, PLACING THE ONE END OF THE TUBE IN COMMUNICATION WITH A SUPPLY OF LIQUID, APPLYING TO THE OTHER END OF THE TUBE SUCTION SUFFICIENT TO DRAW A COLUMN OF LIQUID FROM THE LIQUID SUPPLY UNTO THE TUBE TO A POSITION WHEREIN ITS SURFACE LEVEL LIES ABOVE THE PLUG, TERMINATING THE SUCTION TO LOWER THE COLUMN OF LIQUID UNTIL THE LIQUID SURFACE CONTACTS THE PLUG, AND MAINTAINING THE REMAINING COLUMN OF LIQUID BY CAPILLARY ATTRACTION BETWEEN THE LIQUID AND THE PLUG.

References Cited (Backward Citations)

US2348831A Cited
US2376231A Cited
US2423173A Cited
US2692503A Cited
US3734358A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1978-06-23 1978-12-23 1979-06-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1982-06-23 1982-12-23 1983-06-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1986-06-23 1986-12-23 1987-06-24 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag