Phase and speed control system

Claim 2

A phase and speed control system for synchronizing the rotational velocity and controlling relative rotational phase between a pair of prime movers, each prime mover having associated therewith a tachometer providing tachometer output pulses and a rotational velocity governor, said governor including a governor coil which adjusts the governor to determine the rotational velocity of the prime mover in dependence upon the average current through said governor coil, comprising: first and second means for receiving said tachometer output pulses and for providing first and second synchronization pulse signals in response to said first and second tachometer output pulses, respectively, delay means, responsive to said first means, for providing an adjustably delayed first synchronization pulse signals, and comparator means, responsive to said delayed first synchronization pulse signal from said delay means and to said second synchronization pulse signal, for providing an error signal to the governor coil of the prime mover having the slower rotational velocity, said error signal being a pulse width modulated signal having pulses of a duration proportional to the delay between synchronization pulse signals received by said comparator means, said pulse width modulated signal pulses providing an average current through said governor coil sufficient to hold said pair of prime movers in speed synchronization and said delay means providing adjustable control of the relative rotational phase of said pair of prime movers.

Claim 3

The phase and speed control system of claim 1 in which said comparator means comprises phase comparator means, responsive to said synchronization pulse signals, for providing first and second non-complementary governor control signals, and coil driver means, responsive to said governor control signals, for providing said error signal to the one of said pair of prime movers having the slower initial rotational velocity.

Claim 4

The phase and speed control system of claim 1 in which said first and second means each comprises a squaring amplifier.

Claim 5

The phase and speed control system of claim 1 in which said delay means comprises an adjustable monostable multivibrator.

Claim 6

A phase and speed control system for synchronizing the speed and controlling the phase relationship between a pair of aircraft engines, each of said pair of aircraft engines having associated therewith a tachometer providing tachometer output pulses and a centrifugal governor, including a governor coil, for controlling the pitch of an aircraft propeller driven by the engine associated therewith in response to the current through the coil, comprising: first tachometer input means, responsive to tachometer pulses from the tachometer associated with the first of said pair of engines, for providing a first synchronization pulse train signal, second tachometer input means, responsive to tachometer pulses from the tachometer associated with the second of said pair of engines, for providing a second synchronization pulse train signal, adjustable delay means responsive to said first synchronization pulse train signal from said first tachometer input means, for providing a delayed synchronization pulse train signal, phase comparator means, responsive to said delayed synchronization pulse train signal and said second synchronization pulse train signal for providing a pulse width modulated governor control signal output, and governor coil driver means, responsive to said control signal output for providing a pulse width modulated signal only to the governor coil of the slower of said pair of engines, whereby said engines are brought into speed synchronization by adjustment of the pitch of the propeller driven by the slower of said pair of engines and the relative phase between said pair of engines may be adjusted by means of said adjustable delay means.

Claim 7

A phase and speed control system for synchronizing the speed and controlling the phase relationship between a pair of aircraft engines, each of said pair of aircraft engines having associated therewith a tachometer providing tachometer output pulses and a centrifugal governor, including a governor coil, for controlling the pitch of an aircraft propeller driven by the engine associated therewith in response to the current through the coil, comprising: first tachometer input means, responsive to tachometer pulses from the tachometer associated with the first of said pair of engines, for providing a first synchronization pulse train signal, second tachometer input means, responsive to tachometer pulses from the tachometer associated with the second of said pair of engines, for providing a second synchronization pulse train signal, adjustable delay means responsive to said first synchronization pulse train signal from said first tachometer input means, for providing a delayed synchronization pulse train signal, phase comparator means, responsive to said delayed synchronization pulse train signal and said second synchronization pulse train signal for providing a pulse width modulated governor control signal output, and governor coil driver means, responsive to said control signal output for providing a pulse width modulated signal only to the governor coil of the slower of said pair of engines, whereby said engines are brought into speed synchronization by adjustment of the pitch of the propeller driven by the slower of said pair of engines and the relative phase between said pair of engines may be adjusted by means of said adjustable delay means.

Claim 8

The phase and speed control system of claim 5 in which said phase comparator means provides a governor control signal output which is pulse width modulated in accordance with the phase relationship between said pulse train signals supplied thereto.

Claim 9

The phase and speed control system of claim 6 in which said adjustable delay means comprises an adjustable monostable multivibrator.

Claim 10

The phase and speed control system of claim 6 in which said first and second tachometer means each comprises a squaring amplifier.

Claim 11

The phase and speed control system of claim 6 in which governor coil driver means comprises a pair of Darlington amplifiers, each of said pair of amplifiers connected to a respective one of said governor coils associated with said aircraft engines.

Claim 12

A speed control system for synchronizing the rotational velocities of a pair of prime movers, each prime mover having associated therewith a tachometer providing tachometer output pulses and a rotational velocity governor, said governor including a governor coil which adjusts the governor to determine the rotational velocity of the prime mover in dependence upon the average current through said governor coil, comprising: first and second means for receiving said tachometer output pulses and for providing first and second output pulse signals in response thereto, respectively, and comparator means, responsive to said first and second output pulse signals, for providing an error signal to the governor coil of the prime mover having the slower rotational velocity, said error signal being a pulse width modulated signal having pulses of a duration proportional to the delay between said first and second output pulse signals received by said comparator means, said pulse width modulated signal pulses providing an average current through said governor coil sufficient to hold said pair of prime movers in speed synchronization.

Claim 13

A speed control system for synchronizing the rotational velocities of a pair of prime movers, each prime mover having associated therewith a tachometer providing tachometer output pulses and a rotational velocity governor, said governor including a governor coil which adjusts the governor to determine the rotational velocity of the prime mover in dependence upon the average current through said governor coil, comprising: first and second means for receiving said tachometer output pulses and for providing first and second output pulse signals in response thereto, respectively, and comparator means, responsive to said first and second output pulse signals, for providing an error signal to the governor coil of the prime mover having the slower rotational velocity, said error signal being a pulse width modulated signal having pulses of a duration proportional to the delay between said first and second output pulse signals received by said comparator means, said pulse width modulated signal pulses providing an average current through said governor coil sufficient to hold said pair of prime movers in speed synchronization.