US3881776A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vermiculating polytoroidal thruster
Assignee: United States Department of the Navy
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Filing: 1973-11-23
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Granted: 1975-05-06
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Expires: 1993-11-23
Abstract
Abstract A vermiculating polytoroidal thruster which provides large thrust and braking forces for various devices comprised of a plurality of inflatable bladders mounted on a spool and held in place by end plates. When the bladders are inflated, they squeeze against the inner surface of a tube or tunnel and generate large friction forces for breaking or thrusting. Thrust is provided by vermiculating motion which is generated by inflating one bladder while simultaneously deflating another. A net forward motion is achieved by providing controls for the axial expansion of the bladders. Selective inflation and deflation of certain bladders is controlled by a cycle timer and solenoid valves.
Inventors
- 👤 Richard H Fashbaugh
- 👤 Howard A Gaberson
- 👤 Philip L Stone
- 👤 Donald E Williams
- 👤 John M Stephenson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 09:45
CPC Classifications
E; E21; E21D; E21D9/00; E21D9/10; E21D9/1093; E21B; E21B23/00; E21B23/001
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
67 words
A vermiculating polytoroidal thruster assembly comprising: a. a spool having a cylindrical center and a pair of disc-shaped end plates; b. a plurality of adjacently mounted, toroidal-shaped bladders held between the end plates on the cylindrical center of the spool; c. means for selectively inflating and deflating certain bladders simultaneously in a predetermined sequence; and d. means for confining the axial expansion of each bladder during inflation.
Claim 2
Dependent Claim
67 words
A vermiculating polytoroidal thruster assembly comprising: a. a spool having a cylindrical center and a pair of disc-shaped end plates; b. a plurality of adjacently mounted, toroidal-shaped bladders held between the end plates on the cylindrical center of the spool; c. means for selectively inflating and deflating certain bladders simultaneously in a predetermined sequence; and d. means for confining the axial expansion of each bladder during inflation.
Claim 3
Dependent Claim
21 words
The polytoroidal thruster of claim 1 wherein each bladder has an outisde diameter slightly smaller than the end plates when deflated.
Claim 4
Dependent Claim
46 words
The polytoroidal thruster of claim 2 wherein the means for confining the axial expansion of bladders comprises: a. cylindrical spacers movably mounted on the cylindrical center of the spool between each bladder; and b. means on said spool for limiting the axial motion of the spacers.
Claim 5
Dependent Claim
25 words
The polytoroidal thruster of claim 3 wherein the means for limiting the axial motion of the spacers includes stops on either side of each spacer.
Claim 6
Dependent Claim
17 words
The polytoroidal thruster of claim 4 wherein there are three adjacent bladders held between the end plates.
Claim 7
Dependent Claim
33 words
The polytoroidal thruster of claim 1 wherein the means for confining expansion comprises: a. a cylindrical sheave movably mounted on the cylindrical center; said sheave substantially enclosing at least one of the bladders.
Claim 8
Dependent Claim
16 words
The polytoroidal thruster of claim 6 wherein there are four bladders held between the end plates.
Claim 9
Dependent Claim
15 words
The polytoroidal thruster of claim 7 wherein alternate bladders are enclosed in expansion confining sheaves.
Claim 10
Dependent Claim
41 words
In a tunnel boring machine having a rotating cutting head and a cylindrical body, the improvement comprising: a. at least one polytoroidal thruster assembly as in claim 1 attached to the outer circumference of the cylindrical body of the boring machine.
Claim 11
Dependent Claim
23 words
The apparatus as in claim 9 wherein two polytoroidal thrusters are attached at each end of the cylindrical body of the boring machine.
Claim 12
Dependent Claim
13 words
The apparatus as in claim 10 wherein each polytoroidal thruster has three bladders.
Claim 13
Dependent Claim
29 words
The apparatus of claim 10 wherein each polytoroidal thruster has four bladders and the alternate bladders are substantially enclosed in movably mounted sheaves so that their expansion is limited.
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) | 1978-05-05 | 1978-11-04 | 1979-05-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-05 | 1982-11-04 | 1983-05-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-05 | 1986-11-04 | 1987-05-06 | $7700.00 | Window Closed / Lapsed |