US3731301A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Methods of detecting rotation speed
Assignee: Plessey Handel und Investments AG
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Filing: 1971-07-06
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Granted: 1973-05-01
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Expires: 1991-07-06
Abstract
Abstract Apparatus, preferably fluidic, for providing a control signal indicative of any deviation of the speed of movement of a jet engine or other moving object from a desired speed, comprising a code disc rotated at a speed proportional to the speed of rotation of the jet engine, logic means which cyclically samples the tracks on the code disc at equal time intervals and produces an output signal if the difference between two successive samples is more than a predetermined amount, and integration means which receives and integrates said output signals to provide said control signal. The control signal may be applied to a valve controlling the supply of fuel to the engine so as to govern the engine speed.
Inventors
- 👤 J Davis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 10:45
CPC Classifications
G; G01; G01P; G01P3/00; G01P3/42; G01P3/44; G01P3/48; G01P3/481; G01P3/489; Y; Y10; Y10S; Y10S388/00; Y10S388/90; Y10S388/901; Y10S388/907; Y10S388/912
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
178 words
Apparatus for providing a control signal indicative of any deviation of the speed of movement of a moving object from a desired speed, the apparatus comprising a code disc having a plurality of code tracks thereon and arranged to be rotated at a speed proportional to the speed of movement of the object, storage means connected to monitor each of said code tracks, signal generation means connected to said storage means to supply thereto a series of equally spaced signals each of which is operative to cause the storage means to sample and store the instantaneous values of said code tracks to indicate the instantaneous position of said disc, logic means connected to said storage means and arranged to compare each successive pair of samples of said code tracks with each other and to produce an output signal for every such pair of successive samples that differ by more than a predetermined amount, and integration means connected to said logic means so as to receive and integrate any of said output signals produced to provide said control signal.
Claim 2
Dependent Claim
178 words
Apparatus for providing a control signal indicative of any deviation of the speed of movement of a moving object from a desired speed, the apparatus comprising a code disc having a plurality of code tracks thereon and arranged to be rotated at a speed proportional to the speed of movement of the object, storage means connected to monitor each of said code tracks, signal generation means connected to said storage means to supply thereto a series of equally spaced signals each of which is operative to cause the storage means to sample and store the instantaneous values of said code tracks to indicate the instantaneous position of said disc, logic means connected to said storage means and arranged to compare each successive pair of samples of said code tracks with each other and to produce an output signal for every such pair of successive samples that differ by more than a predetermined amount, and integration means connected to said logic means so as to receive and integrate any of said output signals produced to provide said control signal.
Claim 3
Dependent Claim
46 words
Apparatus as claimed in claim 1, wherein said logic means is arranged to produce a first output signal if any two successive samples differ by more than said predetermined amount and a second and different output signal if such difference is less than said predetermined amount.
Claim 4
Dependent Claim
59 words
Apparatus as claimed in claim 2, wherein said storage means comprises two stores each arranged to store a respective one of two successive samples and said logic means comprises a subtract circuit arranged to compare the contents of the two stores and to produce a first or second output signal in response to a difference in the two contents.
Claim 5
Dependent Claim
116 words
Apparatus as claimed in claim 3, wherein the integration means comprises a reversible counter having an input for counting in one direction connected to said subtract circuit so as to receive any of said first output signals and an input for counting in the opposite direction connected to said subtract circuit so as to receive any of said second output signals, a counter store connected to the reversible counter and means for resetting the counter and for entering its contents into the counter store after a predetermined number of samples, whereby the contents of the counter store represent the difference between the numbers of first and second output signals produced by said predetermined number of samples.
Claim 6
Dependent Claim
29 words
Apparatus as claimed in claim 4, including a digital-to-analogue converter connected to receive the contents of the counter store and the output of the converter comprises said control signal.
Claim 7
Dependent Claim
35 words
Apparatus as claimed in claim 3, wherein said subtract circuit is adapted to provide first and second output signals of equal amplitudes and opposite polarities, and wherein the integration means is a resistive-capacitative integrator circuit.
Claim 8
Dependent Claim
33 words
Apparatus as claimed in claim 1, wherein the tracks on the code disc are arranged to form a Gray code and wherein a Gray-to-binary converter connects said code tracks to said storage means.
Claim 9
Dependent Claim
139 words
Apparatus as claimed in claim 1, wherein the storage means comprises, for each track of the code disc, a bistable sampling circuit arranged on receipt of each signal from said signal generation means to take up a first or or a state, respectively, according to whether the associated track has one or the other value, and the logic means comprises a respective coincidence detector connected to each of said bistable sampling circuits and each having two inputs each connected to a respective one of the outputs of the associated bistable sampling circuit and arranged to produce an output whenever consecutive states of both outputs of the bistable circuit are not the same, and a gate connected to receive the outputs of all the coincidence detectors, any output signal of such gate comprising said output signal of the logic means.
Claim 10
Dependent Claim
73 words
Apparatus as claimed in claim 8, wherein each coincidence detector comprises a pair of AND gates each having one input connected directly to a respective one of the outputs of the associated bistable sampling circuit and another input connected to the same output through a delay circuit, and a NOR gate connected to receive the outputs of the AND gates, the output of the NOR gate being the output of the coincidence detector.
Claim 11
Dependent Claim
31 words
Apparatus as claimed in claim 9, wherein the delay period of each of the delay circuits is equal to the time interval between successive signals provided by said signal generation means.
Claim 12
Dependent Claim
15 words
Apparatus as claimed in claim 8, wherein the integration means comprises a resistive-capacitative integrator circuit.
Claim 13
Dependent Claim
15 words
Apparatus as claimed in claim 1, wherein there are three tracks on the code disc.
Claim 14
Dependent Claim
21 words
Apparatus as claimed in claim 1, including means for adjustably offsetting said control signal to afford variation of said desired speed.
Claim 15
Dependent Claim
67 words
Apparatus for governing the speed of movement of an object, e.g. a prime mover, comprising apparatus as claimed in claim 1 and means for varying the speed of movement of the object, said control signal being operative on said means for varying the speed of the object in a sense tending to minimize any deviation of the speed of movement of the object from the desired speed.
Claim 16
Dependent Claim
36 words
Apparatus as claimed in claim 14, wherein said means for varying said speed of movement comprises a valve which is operative to vary the rate at which a powering medium is supplied to the prime mover.
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) | 1976-04-30 | 1976-10-30 | 1977-05-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-30 | 1980-10-30 | 1981-05-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-30 | 1984-10-30 | 1985-05-01 | $7700.00 | Window Closed / Lapsed |