Patent US3571684A successfully refreshed from Google Patents.
US3571684A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rudder positioning unit for the steering systems of ships
Assignee: Decca Ltd
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Filing: 1969-08-12
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Granted: 1971-03-23
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Expires: 1989-08-12
Abstract
Abstract A rudder positioning unit for the steering systems of ships serves to position the rudder at an angle proportional to a rudder positioning signal received by the unit, and comprises a balance circuit having a balance signal output controlling start and stop of the steering gear of the ship, said balance circuit having inputs for the rudder positioning signal and for a feedback signal from a steering gear simulator, that is started and stopped simultaneously with the steering gear and is capable of simulating the movement of the steering gear, but at a smaller time lag than the latter or practically no time lag at all, preferably in the form of an electrical voltage. Means are provided for continuously effecting slow synchronization of the simulator with the steering gear, and for effecting quick synchronization on occurrence of a predetermined deviation between the simulator and the steering gear. A preferred form of a steering gear simulator is an electronic integrator circuit.
Inventors
- 👤 Mogens Ilsted Bech
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 13:34
CPC Classifications
G; G05; G05D; G05D1/00; G05D1/02; G05D1/0206
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
174 words
A rudder positioning unit comprising a balance circuit having inputs for a rudder positioning signal and a feedback signal, and an output for a balance signal serving as a control signal for starting the steering gear of a ship in one or the other direction and for stopping said steering gear, characterized in that, as a source of said feedback signal, the unit comprises a steering gear position simulator having less timelag than the steering gear, said steering gear position simulator being a time integrator capable of counting forward and backward and controllable by said balance signal coincidentally with said steering gear for starting in one or the other direction and for stopping, thereby to produce, at a signal output thereof, a signal representative of the algebraic sum of the forward and backward counting periods, the signal output of said steering gear position simulator being coupled to the feedback input of said balance circuit to supply said feedback signal, means being provided for slowly synchronizing said steering gear position simulator with said steering gear.
Claim 2
Dependent Claim
174 words
A rudder positioning unit comprising a balance circuit having inputs for a rudder positioning signal and a feedback signal, and an output for a balance signal serving as a control signal for starting the steering gear of a ship in one or the other direction and for stopping said steering gear, characterized in that, as a source of said feedback signal, the unit comprises a steering gear position simulator having less timelag than the steering gear, said steering gear position simulator being a time integrator capable of counting forward and backward and controllable by said balance signal coincidentally with said steering gear for starting in one or the other direction and for stopping, thereby to produce, at a signal output thereof, a signal representative of the algebraic sum of the forward and backward counting periods, the signal output of said steering gear position simulator being coupled to the feedback input of said balance circuit to supply said feedback signal, means being provided for slowly synchronizing said steering gear position simulator with said steering gear.
Claim 3
Dependent Claim
30 words
A rudder positioning unit as in claim 1, and further comprising means for quick synchronization of said simulator with said steering gear upon the occurrence of a predetermined discrepancy therebetween.
Claim 4
Dependent Claim
20 words
A rudder positioning unit as in claim 1, characterized in that the steering gear simulator consists of an integrator circuit.
Claim 5
Dependent Claim
68 words
A rudder positioning unit as in claim 3, characterized in that the integrator circuit has an input connectable in response to said balance signal by way of an input resistor to sources of two different constant voltages, said input being additionally coupled by way of another input resistor to a point of comparison between the signal of the integrator circuit and a signal representative of the rudder position.
Claim 6
Dependent Claim
37 words
A rudder positioning unit as in claim 4, characterized in that a low resistance connection is provided between the input of the integrator circuit and the said point of comparison by way of a two-way threshold switch.
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) | 1974-03-22 | 1974-09-21 | 1975-03-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-22 | 1978-09-21 | 1979-03-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-22 | 1982-09-21 | 1983-03-23 | $7700.00 | Window Closed / Lapsed |