US3818295A — Apparatus and method for control of single-phase …

Claim 1

Independent Claim 267 words

Apparatus for controlling an A-C motor having two stator windings each having a terminal on one side connected to one terminal of an A-C power supply and having respective first and second other side terminals connected through positioner circuitry to the other terminal of the A-C power supply, the motor being of a type which generates torque in one direction when A-C power is applied to the first other side terminal, the motor being electrically brakable upon delivery of D-C power to both of the first and second other side terminals, said control apparatus comprising: a. logic control circuitry having at least one input for receiving a first input signal and responsive thereto to provide a first output signal, said control circuitry further including means for generating a suppression signal in response to the removal of said first input signal, and b. power amplification means having as inputs at least said first output signal and said suppression signal and responsive to said first output signal to provide an output to said positioner circuitry to cause it to deliver A-C power to only the first other side stator terminal and responsive to said suppression signal to provide an output to said positioner circuitry to cause it to deliver D-C power simultaneously to both the first and second other side terminals of said stator, whereby the motor is caused to rotate in one direction by the presence of said first input signal, and the motor is electrically braked in response to the removal of said first input signal and delivery of D-C power simultaneously to both the stator windings.

Claim 2

Dependent Claim 267 words

Apparatus for controlling an A-C motor having two stator windings each having a terminal on one side connected to one terminal of an A-C power supply and having respective first and second other side terminals connected through positioner circuitry to the other terminal of the A-C power supply, the motor being of a type which generates torque in one direction when A-C power is applied to the first other side terminal, the motor being electrically brakable upon delivery of D-C power to both of the first and second other side terminals, said control apparatus comprising: a. logic control circuitry having at least one input for receiving a first input signal and responsive thereto to provide a first output signal, said control circuitry further including means for generating a suppression signal in response to the removal of said first input signal, and b. power amplification means having as inputs at least said first output signal and said suppression signal and responsive to said first output signal to provide an output to said positioner circuitry to cause it to deliver A-C power to only the first other side stator terminal and responsive to said suppression signal to provide an output to said positioner circuitry to cause it to deliver D-C power simultaneously to both the first and second other side terminals of said stator, whereby the motor is caused to rotate in one direction by the presence of said first input signal, and the motor is electrically braked in response to the removal of said first input signal and delivery of D-C power simultaneously to both the stator windings.

Claim 3

Dependent Claim 94 words

The apparatus of claim 1, in which said logic control circuitry means further comprises: first delay means connected to said first input and being responsive to the removal of said first input signal to delay the generation of the suppression signal to deliver d-c power to both the first and second terminals only after a first predetermined time interval following the removal of said first input signal, whereby the initiation of the braking action may be delayed for a predetermined time following the removal of the first input signal from the first circuit input.

Claim 4

Dependent Claim 98 words

The apparatus of claim 2, further comprising: a. a synchronized signal generator connected to the a-c line voltage of the a-c power supply said generator being responsive to said line voltage to emit a first synchronized signal, in synchronism therewith, and b. means to pass said first synchronized signal to said first delay means, said first delay means being actuated by receipt of said first synchronized signal following removal of said first input signal to enable said braking means to generate said suppression signal only after said first predetermined time interval following receipt of said first synchronized signal.

Claim 5

Dependent Claim 116 words

The apparatus of claim 1 in which said logic control circuitry means further comprises: braking timer means connected to said one input and being responsive to the removal of the one input signal for generating a brake timing signal of predetermined duration for providing said suppression signal for the period of said predetermined duration for actuating said positioner circuit to prevent flow of current through the windings in one direction, and which, in combination with a phase control signal, enables current flow through the windings in the other direction, whereby the maximum duration of the braking period may be governed by the characteristics of the braking timer means governing the duration of the brake timing signal.

Claim 6

Dependent Claim 32 words

The apparatus of claim 4, further comprising: means to regulate the r.m.s. value of the d-c braking power delivered to the stator windings, whereby th level of braking power can be governed.

Claim 7

Dependent Claim 142 words

The apparatus of claim 5, in which said regulating means comprises: a. a synchronized signal generator connectd to the a-c line voltage of the a-c power supply and responsive thereto to generate a train of second synchronized signals in synchronism with said line voltage, and b. a second delay means connected to said synchronized signal generator and being responsive to receipt of each said second synchronized signal to generate said phase control signals, each said phase control signal having a predetermined duration, whereby d-c power is applied to the windings during periods of coincidence of said brake timing signal and said phase control signals, the duration of the brake timing signal establishing the total length of braking time and the duration of each said phase control signal regulating the value of the d-c power applied to the windings during the braking period.

Claim 8

Dependent Claim 33 words

The apparatus of claim 1, further comprising: means to regulate the rms value of the d-c power which is deliverd to both stator windings, whereby the level of braking power can be governed.

Claim 9

Dependent Claim 18 words

The apparatus of claim 1, further comprising: means for controlling the duration of said application of d-c power.

Claim 10

Dependent Claim 127 words

The apparatus of claim 1, in which the motor generates torque in a direction opposite to the one direction when a-c power is applied to only the second terminal said logic control circuitry comprising: a. means to receive a second input signal, b. means connected to sAid second input receiving means and responsive to the presence of said second input signal to deliver a-c power from said a-c power supply to the second terminal to cause the motor to rotate in said opposite direction, and c. means responsive to the removal of said second input signal and connected to the positioner circuitry to actuate the positioner circuitry to provide d-c braking power to both the first and second terminals only after said second input signal is removed.

Claim 11

Dependent Claim 53 words

The apparatus of claim 2, further comprising: means connected to said logic control circuitry and responsive to said suppression signal to block inputs at said first input signal for the duration of said suppression signal whereby any spurious input signals at said first input are blocked, so as not to interfere with braking.

Claim 12

Dependent Claim 77 words

The apparatus of claim 3, in which said control circuit means further comprises: braking timer means connected to said first input and being responsive to the removal of the first input signal for generating a brake timing signal for providing said suppression signal for only a predetermined braking time period, whereby the maximum duration of the braking period may be governed by he condition of the braking timer means governing the duration of the brake timing signal.

Claim 13

Dependent Claim 54 words

The apparatus of claim 2, further comprising: braking timer means connected to said first input and being responsive to the removal of the first input signal for generating a brake timing signal for enabling, in combination with a phase control signal, the generation of said suppression signal for only a predetermined braking time period.

Claim 14

Dependent Claim 189 words

The apparatus of claim 1 in which the positioner circuitry comprises: a. a pair of first and second unidirectional devices connected in opposite directions in parallel between said other terminal of the a-c power supply and the first terminal, the conductive direction of said first unidirectional device being toward said first terminal, and b. a third unidirectional device connected between said other terminal of said a-c power supply and said second terminal and having its conductive direction toward said second terminal, each of said unidirectional devices having a control terminal, the potential on which determining whether its associated unidirectional device is conductive in its direction of conduction, or is nonconductive, said control terminals being connected to said power amplification means to render said unidirectional devices controllable by said control ciuit means in order to control the delivery of power to the first and second terminals, whereby a-c power to rotate the motor may be applied to said first terminal by rendering conductive only said first and second unidirectional devices, and d-c braking power may be applied to both terminals by rendering conductive only said first and third unidirectional devices.

Claim 15

Dependent Claim 56 words

The apparatus of claim 13, in which said power amplification means comprises: a. clock generator means responsive to said first input to apply potential to said control terminals of only said first and third unidirectional devices, to render them conductive, and b. logic gate means responsive to said suppression signal to block said second unidirectional device.

Claim 16

Dependent Claim 18 words

The apparatus of claim 14, further comprising: amplifier means to amplify the signals emitted by said clock generator.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1977-06-17	1977-12-17	1978-06-18	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1981-06-17	1981-12-17	1982-06-18	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1985-06-17	1985-12-17	1986-06-18	$7700.00	Window Closed / Lapsed

Apparatus and method for control of single-phase a-c motors

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