Patent US4629149A successfully refreshed from Google Patents.
US4629149A
Expired / Lapsed
US
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Method of and apparatus for de-icing an elastically deformable sheet member
Assignee: Short Brothers PLC
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Filing: 1984-08-21
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Granted: 1986-12-16
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Expires: 2004-08-21
Abstract
Abstract An economical method of, and apparatus for, de-icing the skin panels (25) of aircraft employs electromagnetic solenoid actuators (1) which use normal supply voltages (43) available on aircraft to flex the skin panels slowly and rely upon abrupt termination (S) of the flexing pressure and the consequent fast natural elastic relaxation of the panels to break the bond between the panels and the ice accreted thereon, to shrug off the ice from the panels.
Inventors
- 👤 Oliver S. Carson
- 👤 George McMurtry
- 👤 James E. Carrington
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 18:15
CPC Classifications
B; B64; B64D; B64D15/00; B64D15/16; B64D15/163
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
104 words
A method of de-icing an exposed surface of a resilient sheet member, which method comprises the steps of: i. applying a force that increases with time to the sheet member to deform the sheet member relatively slowly from a relaxed disposition to an elastically loaded maximum deflection disposition; ii. abruptly removing said force to allow the sheet member to oscillate freely at its natural frequency at a relatively fast rate of displacement and with decaying amplitude as the sheet member returns to the relaxed disposition for de-icing the sheet member; and iii. repeating steps (i) and (ii) for as long as de-icing is required.
Claim 2
Independent Claim
104 words
A method of de-icing an exposed surface of a resilient sheet member, which method comprises the steps of: i. applying a force that increases with time to the sheet member to deform the sheet member relatively slowly from a relaxed disposition to an elastically loaded maximum deflection disposition; ii. abruptly removing said force to allow the sheet member to oscillate freely at its natural frequency at a relatively fast rate of displacement and with decaying amplitude as the sheet member returns to the relaxed disposition for de-icing the sheet member; and iii. repeating steps (i) and (ii) for as long as de-icing is required.
Claim 3
Dependent Claim
32 words
A method according to claim 1 characterized in that the force which is provided for displacing the sheet member to the elastically loaded maximum deflection disposition increases continuously during each application thereof.
Claim 4
Dependent Claim
36 words
A method according to claim 1 characterized in that the force which is provided for displacing the sheet member to the elastically loaded maximum deflection disposition increases in a plurality of steps during each application thereof.
Claim 5
Independent Claim
47 words
A method according to any one of the preceding claims characterized by the steps of: i. monitoring a condition of the sheet member at a time when it is subject to said force; and ii. controlling the force in dependence upon a monitored value of the condition.
Claim 6
Dependent Claim
15 words
A method according to claim 4 wherein said condition is strain within the sheet member.
Claim 7
Dependent Claim
20 words
A method according to claim 4 wherein said condition is the magnitude of the force acting on the sheet member.
Claim 8
Dependent Claim
29 words
A method according to claim 6 wherein the magnitude of the force is measured as a magnitude of electrical current flowing through an electromechanical actuator which generates the force.
Claim 9
Dependent Claim
135 words
Apparatus for de-icing an exposed surface of a resilient sheet member that is attached to a support structure, the apparatus comprising means connected to the support structure for applying a force transversely to an unsupported region of the sheet member; means for controlling said force applying means to deliver a force that increases with time to deform the sheet member relatively slowly from a relaxed disposition to an elastically loaded maximum deflection disposition; means to remove abruptly said force to allow the sheet member to oscillate freely at its natural frequency at a relatively fast rate of displacement and with decaying amplitude as the sheet member returns to the relaxed disposition for de-icing the sheet member; and means for effecting said increasing force application and abrupt removal repeatedly for as long as de-icing is required.
Claim 10
Dependent Claim
135 words
Apparatus for de-icing an exposed surface of a resilient sheet member that is attached to a support structure, the apparatus comprising means connected to the support structure for applying a force transversely to an unsupported region of the sheet member; means for controlling said force applying means to deliver a force that increases with time to deform the sheet member relatively slowly from a relaxed disposition to an elastically loaded maximum deflection disposition; means to remove abruptly said force to allow the sheet member to oscillate freely at its natural frequency at a relatively fast rate of displacement and with decaying amplitude as the sheet member returns to the relaxed disposition for de-icing the sheet member; and means for effecting said increasing force application and abrupt removal repeatedly for as long as de-icing is required.
Claim 11
Dependent Claim
32 words
Apparatus as claimed in claim 8 wherein the means for applying force to the sheet member comprises an electromagnetic actuator, and means for controlling the flow of electrical current to the actuator.
Claim 12
Dependent Claim
19 words
Apparatus as claimed in claim 9 wherein the control means includes a variable resistance controlled by a logic circuit.
Claim 13
Dependent Claim
16 words
Apparatus as claimed in claim 10 wherein the variable resistance is a transistor or transistor-based device.
Claim 14
Dependent Claim
32 words
Appratus as claimed in claim 11 wherein the variable resistance is a transistor having a base, and the logic circuit continuously varies a bias on the base of the transistor variable resistance.
Claim 15
Dependent Claim
83 words
Apparatus as claimed in claim 11 wherein the variable resistance is a device comprising first and second transistors in parallel with each other, the first transistor having a resistance in series with it, and the logic circuit is such as to switch the first and second transistors in sequence, so that the first transistor is rendered conductive before the second transistor and the force generated by the actuator is thereby made to increase step-wise, upon the onset of conductivity of the second transistor.
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) | 1989-12-15 | 1990-06-16 | 1990-12-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-12-15 | 1994-06-16 | 1994-12-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-12-15 | 1998-06-16 | 1998-12-16 | $7700.00 | Window Closed / Lapsed |