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US3557611A Expired / Lapsed US ⏱️ 0.0 years remaining

Tonometer with correct usage indicator

Assignee: Computer Instruments Corp
•
Filing: 1968-11-01
•
Granted: 1971-01-26
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Expires: 1988-11-01
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Abstract

Abstract PRESSURE GAUGE AS AN INDICATION OF SUCH CORRECT OPERATION OF THE INSTRUMENT. IN A PROJECTING PLUNGER TYPE OF TONOMETER, A CIRCULAR ORIFICE IS DISPOSED AROUND THE PLUNGER IN THE END WALL OF THE PROBE COMMUNICATING WITH A CHAMBER SUPPLIED WITH AIR FROM A LOW CAPACITY PUMP. PROPER APPLICATION OF THE TONOMETER TO AN EYEBALL WILL OCCLUDE THE ENTIRE CIRCULAR ORIFICE CAUSING THE AIR PRESSURE WITHIN THE AFORESAID CHAMBER TO BUILD UP TO THE MAXIMUM CAPACITY OF THE PUMP WITHIN THE TIME NECESSARY FOR THE INSTRUMENT TO TAKE A TONOMETRIC READING WHICH PRESSURE CAN BE READ FROM A

Inventors

  • 👤 Herbert H Adise

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 23:51
CPC Classifications
A; A61; A61B; A61B3/00; A61B3/10; A61B3/16

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1974-01-25 1974-07-27 1975-01-26 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1978-01-25 1978-07-27 1979-01-26 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1982-01-25 1982-07-27 1983-01-26 $7700.00 Window Closed / Lapsed

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