US3582550A — Self-synchronizing graphic transmission and repro…

Claim 1

Independent Claim 298 words

In a rotary drum facsimile system having a rotating drum for operation at a synchronous speed with no more than a predetermined angular misalignment with respect to a reference derived from a remotely generated synchronizing signal, the improvement comprising a drum synchronizer for angularly aligning said drum on receipt of said synchronizing signal, the synchronizer comprising: A. a motor driving said drum at a selected speed in accordance with inputs applied thereto; B. means for periodically generating drum signals at a rate proportional to the rotary speed of said drum and at times indicative of the angular misalignment; C. a clock 1. generating timing intervals a. having a duration equal to the rotational period of the drum when the drum is rotating at the synchronous speed; b. beginning with the synchronization signal; c. the start of each new timing interval providing a reference for the measurement of the angular misalignment during the said interval; D. decoding means 1. associated with the clock and providing outputs during different time subintervals corresponding to fractions of the timing period; 2. having means for gating the clock outputs with the drum signals to generate command signals indicative of the time difference between the reference signal and the drum signal in accordance with the particular clock subinterval during which the drum signal occurs; E. a frequency generator responsive to the command signals for operation at one of a plurality of frequencies in accordance therewith; and F. means connectiNg said frequency generator in driving relation with said motor to drive said motor at a speed dependent on said angular misalignment, the frequency generator changing the driving speed toward the synchronous speed in accordance with the different command signals generated by said gating means until the angular misalignment is reduced to within a predetermined amount.

Claim 2

Dependent Claim 298 words

In a rotary drum facsimile system having a rotating drum for operation at a synchronous speed with no more than a predetermined angular misalignment with respect to a reference derived from a remotely generated synchronizing signal, the improvement comprising a drum synchronizer for angularly aligning said drum on receipt of said synchronizing signal, the synchronizer comprising: A. a motor driving said drum at a selected speed in accordance with inputs applied thereto; B. means for periodically generating drum signals at a rate proportional to the rotary speed of said drum and at times indicative of the angular misalignment; C. a clock 1. generating timing intervals a. having a duration equal to the rotational period of the drum when the drum is rotating at the synchronous speed; b. beginning with the synchronization signal; c. the start of each new timing interval providing a reference for the measurement of the angular misalignment during the said interval; D. decoding means 1. associated with the clock and providing outputs during different time subintervals corresponding to fractions of the timing period; 2. having means for gating the clock outputs with the drum signals to generate command signals indicative of the time difference between the reference signal and the drum signal in accordance with the particular clock subinterval during which the drum signal occurs; E. a frequency generator responsive to the command signals for operation at one of a plurality of frequencies in accordance therewith; and F. means connectiNg said frequency generator in driving relation with said motor to drive said motor at a speed dependent on said angular misalignment, the frequency generator changing the driving speed toward the synchronous speed in accordance with the different command signals generated by said gating means until the angular misalignment is reduced to within a predetermined amount.

Claim 3

Dependent Claim 70 words

A drum synchronizer according to claim 1 in which said clock comprises a plurality of bistable elements connected to provide a serial counting sequence, said decoders being connected to selected ones of said elements to establish distinct time subintervals within the clock counting period and being adapted to provide outputs on selected lines on receipt of drum signals in accordance with the time subintervals within which the drum pulses occur.

Claim 4

Dependent Claim 121 words

having means for gating the clock outputs with the drum signals to generate command signals indicative of the time difference between the reference signal and the drum signal in accordance with the particular clock subinterval during which the drum signal occurs; E. a frequency generator responsive to the command signals for operation at one of a plurality of frequencies in accordance therewith; and F. means connectiNg said frequency generator in driving relation with said motor to drive said motor at a speed dependent on said angular misalignment, the frequency generator changing the driving speed toward the synchronous speed in accordance with the different command signals generated by said gating means until the angular misalignment is reduced to within a predetermined amount.

Claim 5

Dependent Claim 121 words

having means for gating the clock outputs with the drum signals to generate command signals indicative of the time difference between the reference signal and the drum signal in accordance with the particular clock subinterval during which the drum signal occurs; E. a frequency generator responsive to the command signals for operation at one of a plurality of frequencies in accordance therewith; and F. means connectiNg said frequency generator in driving relation with said motor to drive said motor at a speed dependent on said angular misalignment, the frequency generator changing the driving speed toward the synchronous speed in accordance with the different command signals generated by said gating means until the angular misalignment is reduced to within a predetermined amount.

Claim 6

Dependent Claim 193 words

providing an output on one of a plurality of lines on receipt of said drum signal to provide a direct indication of the time subinterval, measured with respect to the start of each timing interval, in which said drum signal occurs; F. a plurality of bistable elements, equal in number to the number of discrete time subintervals into which each timing interval is divided, all but one of the elements being connected to the decoder for energization thereby, the other of the elements being energized by the synchronizing signal, the energization of each element corresponding to detection of the drum pulse in a particular time subinterval and thereby providing a quantized indication of the angular misalignment; G. a plurality of moNostable multivibrators connected to all but one of said elements and adapted to generate command signals in accordance with the energization state of the elements and indicative of the angular misalignment, said command signals being supplied to the frequency generator at selected stages and selected times to set the generator to a frequency corresponding to the measured angular misalignment and chosen to reduce the misalignment to an accepted tolerance within a given time.

Claim 7

Dependent Claim 193 words

providing an output on one of a plurality of lines on receipt of said drum signal to provide a direct indication of the time subinterval, measured with respect to the start of each timing interval, in which said drum signal occurs; F. a plurality of bistable elements, equal in number to the number of discrete time subintervals into which each timing interval is divided, all but one of the elements being connected to the decoder for energization thereby, the other of the elements being energized by the synchronizing signal, the energization of each element corresponding to detection of the drum pulse in a particular time subinterval and thereby providing a quantized indication of the angular misalignment; G. a plurality of moNostable multivibrators connected to all but one of said elements and adapted to generate command signals in accordance with the energization state of the elements and indicative of the angular misalignment, said command signals being supplied to the frequency generator at selected stages and selected times to set the generator to a frequency corresponding to the measured angular misalignment and chosen to reduce the misalignment to an accepted tolerance within a given time.

Claim 8

Dependent Claim 45 words

adapted to initiate a timing interval on receipt of the synchronization signal, said timing interval repeating itself as long as said clock is energized, the beginning of each timing interval serving as a reference for measuring the angular misalignment of the drum, E. a decoder

Claim 9

Dependent Claim 45 words

adapted to initiate a timing interval on receipt of the synchronization signal, said timing interval repeating itself as long as said clock is energized, the beginning of each timing interval serving as a reference for measuring the angular misalignment of the drum, E. a decoder

Claim 10

Dependent Claim 52 words

A drum synchronizer according to claim 1 in which said clock subintervals form successive time segments corresponding to increasing amounts of misalignment between the drum and the reference signal, the drum being driven successively at different speeds corresponding to the successive time segments until the misalignment is reduced to a predetermined amount.

Claim 11

Dependent Claim 84 words

A drum synchronizer according to claim 1 in which said frequency generator comprises a plurality of bistable elements connected to each other in serial counting relation to provide an output at a rate that is a submultiple of the rate of an input applied to it, said command signals being applied to selected stages thereof to alter the normal counting sequence at preselected times to thereby alter the rate at which the outputs are supplied by the generator in accordance with the command signals.

Claim 12

Dependent Claim 51 words

A drum synchronizer according to claim 4 in which the frequency generator is adapted to receive command signals of differing duration to alter the output frequency thereof, a command signal of a first duration increasing the generator output frequency and a command signal of a second longer duration decreasing its frequency.

Claim 13

Dependent Claim 89 words

A drum synchronizer according to claim 1 in which the means for generating said drum signals comprises a light source, a mirror mounted on the drum for rotation therewith and located at a selected angular orientation with respect to a reference position on the drum, said mirror being periodically illuminated by said light source as said drum rotates with respect to said source, and means for detecting light reflected from said mirror when so illuminated to provide a drum pulse signal indicative of the drum orientation at selected times.

Claim 14

Dependent Claim 115 words

A drum synchronizer according to claim 1 in which said command signals are applied to said frequency generator through a frequency control circuit comprising: A. a set of bistable elements, there being at least one such element for each different subinterval in excess of one into which the counting period of the clock is divided, said elements being set to one of two states in accordance with the speed at which the drum is to rotate; and B. at least one monostable multivibrator energizable by said elements at selected times to inject signals into said frequency generator at selected locations to alter the frequency of the generator in accordance with the state of said elements.

Claim 15

Dependent Claim 77 words

A drum synchronizer according to claim 1 in which said at least one multivibrator accepts at least two different inputs and provides at least two different outputs in accordance therewith, a first of said inputs triggering the multivibrator to provide a pulse output therefrom and a second of said inputs altering the length of said output pulse to thereby set the frequency of the generator to one of at least two different frequencies dependent on said inputs.

Claim 16

Dependent Claim 54 words

A drum position synchronizer according to claim 8 in which said multivibrators comprise first and second coincidence gates connected together by an R-C coupling circuit establishing the time constant of the pulse output from said gate, said switch being connected across a portIon of the resistance to vary the time constant of the multivibrator.

Claim 17

Dependent Claim 56 words

A drum position synchronizer according to claim 9 in which said switch comprises a transistor having a collector-emitter circuit connected across a portion of the resistance and a base circuit for energization at selected times by said second input times to short the resistance across said collector-emitter circuit and decrease the time constant of said multivibrator.

Claim 18

Dependent Claim 91 words

A drum pulse synchronizer according to claim 2 which includes a single bistable element for each time subinterval into which said clock period is divided, one of said elements being responsive to the synchronizing signal to enable operation of the frequency generator at a selected rate in excess of the synchronous rate, each of the remaining elements being responsive to a different one of the outputs of said clock to enable operation of the frequency generator at differing rates, including the synchronous rate, depending on the angular misalignment between the drums.

Claim 19

Dependent Claim 58 words

A drum pulse synchronizer according to claim 11 in which all but one of the bistable elements are connected to supply inputs to a pair of monostable multivibrators, one of said inputs being connected to a switch in one of said multivibrators to control the time constant of the multivibrator and therefore the length of its output pulse.

Claim 20

Dependent Claim 72 words

A drum synchronizer according to claim 1 in which the frequency generator drives the drum motor at successively decreasing rates, each in excess of the synchronous rate, dependent on the angular misalignment between the drum pulse and the synchronizing signal when said misalignment is less than a first predetermined magnitude and drives said drum motor at a second rate, less than the synchronous rate, when the misalignment exceeds said first predetermined value.

Claim 21

Dependent Claim 125 words

In a rotary drum facsimile system, apparatus for synchronizing the angular orientation of a pair of drums adapted to be operated at a common synchronous speed within a fixed time interval after receipt of a common synchronization signal, the drums being separated from each other and each having associated therewith: A. a variable speed synchronous motor connected to a corresponding drum for driving the drum at selected speeds in accordance with the inputs to said motor; B. a frequency generator adapted to drive said motor at a rate dependent on command signals selectively applied to the generator; C. means associated with each said drum for periodically generating a drum signal indicative of the angular orientation of a reference position on the drum; D. a clock

Claim 22

Dependent Claim 125 words

In a rotary drum facsimile system, apparatus for synchronizing the angular orientation of a pair of drums adapted to be operated at a common synchronous speed within a fixed time interval after receipt of a common synchronization signal, the drums being separated from each other and each having associated therewith: A. a variable speed synchronous motor connected to a corresponding drum for driving the drum at selected speeds in accordance with the inputs to said motor; B. a frequency generator adapted to drive said motor at a rate dependent on command signals selectively applied to the generator; C. means associated with each said drum for periodically generating a drum signal indicative of the angular orientation of a reference position on the drum; D. a clock

Claim 23

Dependent Claim 77 words

Apparatus according to claim 14 in which said frequency generator is capable of operation at at least one frequency respectively above and below the synchronous frequency as well as at the synchronous frequency, said generator initially being set by the bistable elements to operate at a frequency in excess of the synchronous frequency and thereafter being reset to operate at a frequency, other than the synchronous frequency, which is dependent on the angular misalignment of the drum.

Claim 24

Dependent Claim 59 words

Apparatus according to claim 15 in which the frequency generator is reset to operate at a frequency above the synchronous frequency when the angular misalignment is less than a predetermined amount and is reset to operate at a frequency below the synchronous frequency when the angular misalignment is greater than a predetermined amount, whereby the misalignment is efficiently reduced.

Claim 25

Dependent Claim 56 words

Apparatus according to claim 14 in which at least one of the multivibrators is adapted to receive a pair of inputs and to supply a command signal on reception thereof, the duration of the command signal being determined by one of said inputs and the time of occurrence of said signal being determined by the other.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1974-05-31	1974-11-30	1975-06-01	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1978-05-31	1978-11-30	1979-06-01	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1982-05-31	1982-11-30	1983-06-01	$7700.00	Window Closed / Lapsed

Self-synchronizing graphic transmission and reproduction system

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