US5299938A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Display apparatus
Assignee: Individual
•
Filing: 1991-01-31
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Granted: 1994-04-05
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Expires: 2011-01-31
Abstract
Abstract An apparatus for illustrating the operation of an Archimedes screw. Two passages (8,9) are defined which together form a single closed loop passageway. A first passage (8) is generally linear and a second passage (9) is of helical form and is connected at its ends to the ends of the first passage. The walls of the two passages are transparent such that the movement of fluid (10) can be clearly seen. The first and second passages are arranged such that if the first passage (8) is positioned at a predetermined inclination to the vertical fluid can be transferred through the second passage (9) from the lower to the upper end of the first passage by rotating the apparatus about an axis extending parallel to the length of the first passage. The second passage (9) may be in the form of a helical tube wound around the outside of a straight tube defining the first passage (8) .
Inventors
- 👤 Barry S. Waltho
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 03:34
CPC Classifications
G; G09; G09B; G09B23/00; G09B23/06; G09B23/08; G09B23/12
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
112 words
A display apparatus defining a passageway within which a body of fluid may be retained, wherein the passageway comprises a closed loop including an elongate first passage and a helical second passage which is connected to and extends between the ends of the first passage, the walls of at least the second passage being transparent, and the second passage being formed such that if the first passage is positioned with a predetermined inclination to the vertical, fluid can be transferred through the second helical passage from the lower to the upper end of the first passage by rotating the apparatus about an axis extending parallel to the length of the first passage.
Claim 2
Dependent Claim
112 words
A display apparatus defining a passageway within which a body of fluid may be retained, wherein the passageway comprises a closed loop including an elongate first passage and a helical second passage which is connected to and extends between the ends of the first passage, the walls of at least the second passage being transparent, and the second passage being formed such that if the first passage is positioned with a predetermined inclination to the vertical, fluid can be transferred through the second helical passage from the lower to the upper end of the first passage by rotating the apparatus about an axis extending parallel to the length of the first passage.
Claim 3
Dependent Claim
16 words
An apparatus according to claim 1, wherein the helical second passage extends around the first passage.
Claim 4
Dependent Claim
20 words
An apparatus according to claim 2 wherein the second passage is defined by a tube wound around the first passage.
Claim 5
Dependent Claim
23 words
An apparatus according to claim 3, wherein the passageway is defined by a closed loop of tube defining the first and second passageways.
Claim 6
Dependent Claim
18 words
An apparatus according to claim 4, wherein the closed loop of tube is received within a cylindrical casing.
Claim 7
Dependent Claim
28 words
An apparatus according to claim 4, wherein at least one end of the first passage communicates with a cavity extending beyond an adjacent end of the second passage.
Claim 8
Dependent Claim
54 words
An apparatus according to claim 2, wherein the first passage is defined by a first tube located coaxially within a second tube, the first tube communicating with opposite ends of the second tube, and a helical web is disposed between the first and second tubes to define with the tubes the said second passageway.
Claim 9
Dependent Claim
16 words
An apparatus according to claim 1, wherein the second passage is enclosed within the first passage.
Claim 10
Dependent Claim
16 words
An apparatus according to claim 1, wherein the passage way is partially filled with a liquid.
Claim 11
Dependent Claim
26 words
An apparatus according to claim 1, wherein the passageway is substantially fully filled with at least two immiscible liquids of different densities and different optical properties.
Claim 12
Dependent Claim
29 words
An apparatus according to claim 1 comprising a spindle aligned with the said axis and mounted on a support to enable rotation of the passageway about the said axis.
References Cited (Backward Citations)
US2752725A
Cited
US2714260A
Cited
US2871617A
Cited
CH473583A
Cited
US4595369A
Cited
FR2598471A1
Cited
US4778430A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-04-04 | 1997-10-04 | 1998-04-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-04-04 | 2001-10-04 | 2002-04-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-04-04 | 2005-10-04 | 2006-04-05 | $7700.00 | Window Closed / Lapsed |