Patent US2521475A successfully refreshed from Google Patents.
US3634853A
Expired / Lapsed
US
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Liquid displacement encoder
Assignee: Individual
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Filing: 1970-06-08
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Granted: 1972-01-11
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Expires: 1990-06-08
Abstract
Abstract A digitizer is disclosed, wherein the relative change in volume between two fluids is transposed directly into a digital code, in that a pattern of elemental liquid columns in a capillary is displaced relative to a pickup means operating transverse to the capillary. Different arrangements for obtaining higher significant digits as well as doubling the resolution is disclosed.
Inventors
- 👤 Charles P Hedges
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 12:51
CPC Classifications
G; G01; G01L; G01L9/00; G01L9/0091; G01K; G01K1/00; G01K1/02; G01K1/024; H; H03; H03M; H03M1/00; H03M1/12; H03M1/22; H03M1/24; H03M1/28; H03M1/30
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
263 words
A liquid displacement encoder, comprising: a capillary tube having first and second ends each exposed to expanding and contracting fluids; a plurality of first elemental columns of a first liquid in the tube disposed therein in regular, spaced-apart relationship and occupying a particular length in the tube equivalent of the scale length of the encoder, there being a first and a last of the columns of the first plurality respectively closest to the first and second end of the tube but in physical separation from each of the expanding fluids; a plurality of elemental columns of a second liquid interposed between the first elemental columns in the tube, the first and second liquids being immiscible and having different particularly detectable characteristics, the first and second alternatingly spaced columns together establishing the length of a scale; pickup means operatively coupled to the tube and effective across the tube''s diameter over an area smaller than the length of any of the columns to detect absence of a first or of a second column in a particular location of the tube, the scale as defined by the columns of the pluralities having particular scale reference value when in a particular relative position to the pickup means; first means connected to the pickup means to derive therefrom digital representation of low significance of the Relative position of the plurality of columns in the tube; and second means operatively coupled to the first means and likewise operating in response to the balance of fluid expansion and contraction to provide digital representation of the relative displacement of higher significance.
Claim 2
Dependent Claim
263 words
A liquid displacement encoder, comprising: a capillary tube having first and second ends each exposed to expanding and contracting fluids; a plurality of first elemental columns of a first liquid in the tube disposed therein in regular, spaced-apart relationship and occupying a particular length in the tube equivalent of the scale length of the encoder, there being a first and a last of the columns of the first plurality respectively closest to the first and second end of the tube but in physical separation from each of the expanding fluids; a plurality of elemental columns of a second liquid interposed between the first elemental columns in the tube, the first and second liquids being immiscible and having different particularly detectable characteristics, the first and second alternatingly spaced columns together establishing the length of a scale; pickup means operatively coupled to the tube and effective across the tube''s diameter over an area smaller than the length of any of the columns to detect absence of a first or of a second column in a particular location of the tube, the scale as defined by the columns of the pluralities having particular scale reference value when in a particular relative position to the pickup means; first means connected to the pickup means to derive therefrom digital representation of low significance of the Relative position of the plurality of columns in the tube; and second means operatively coupled to the first means and likewise operating in response to the balance of fluid expansion and contraction to provide digital representation of the relative displacement of higher significance.
Claim 3
Dependent Claim
22 words
A liquid encoder as in claim 1, the first columns of liquid having length approximately 1 1/2 the diameter of the capillary.
Claim 4
Dependent Claim
24 words
A liquid encoder as in claim 1, the first and second columns having similar length, each in excess of the diameter of the capillary.
Claim 5
Dependent Claim
42 words
A liquid encoder as in claim 1, the pickup means including a pair f electrodes, there being electrical means to bias the electrodes, the first and second liquids having different conductivity, the electrodes responsive to conductance through the capillary across the diameter.
Claim 6
Dependent Claim
32 words
A liquid encoder as in claim 1, the pickup means providing a radiation beam across the tube and detecting absorption therein, the first and second liquids differing in transmittance of the radiation.
Claim 7
Dependent Claim
33 words
A liquid encoder as in claim 3, the pickup means including first and second pickup means disposed by an odd-numbered multiple of half a column length apart from each other along the tube.
Claim 8
Dependent Claim
34 words
A liquid encoder as in claim 1, the second means including counter means connected to the pickup means and responsive to directional displacement of the columns in the capillary to obtain higher significant digits.
Claim 9
Dependent Claim
41 words
A liquid encoder as in claim 1, the first end merging into a flask filled with a particular fluid balancing the position of the columns in the capillary in their relative position to the second end and to the pickup means.
Claim 10
Dependent Claim
19 words
A liquid encoder as in claim 8, the second end of the capillary merging into a second fluid-filled flask.
Claim 11
Dependent Claim
23 words
A liquid encoder as in claim 1, there being means to provide controlled pressure to the first and second ends of the capillary.
Claim 12
Dependent Claim
95 words
A liquid encoder as in claim 1, the second means including a second capillary having ends exposed to the fluids acting on the first capillary, the second capillary having at least one first liquid column, having length which is an integral multiple of the length of the first column of the first capillary, and having pickup means oriented to the first column in the second capillary to establish a phase relation thereto to establish a higher significant digit for the measurement established by the relation between pickup means and first columns in the first capillary.
Claim 13
Dependent Claim
65 words
A liquid encoder as in claim 1, including a second capillary having ends exposed to the fluids acting on the first capillary, and including columns of different liquids, there being second pickup means, the columns in the second capillary having position relative to the second pickup means, corresponding to a phase shift as between the columns in the first capillary and the first pickup means.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-01-10 | 1975-07-12 | 1976-01-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-10 | 1979-07-12 | 1980-01-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-10 | 1983-07-12 | 1984-01-11 | $7700.00 | Window Closed / Lapsed |