Starting control circuit for an A.C. motor
First Claim
1. A starting control circuit for an alternating current motor having a run winding and a start winding and a mechanical rotational output comprising:
- an alternating current source;
reference means for producing a reference signal;
first control means responsive to said reference signal and the frequency of said alternating current source for producing a first control signal;
sensor means for sensing a predetermined amount of rotational movement of said mechanical rotational output and producing a sensor signal indicative thereof;
second control means responsive to said reference signal and said sensor signal for producing a second control signal and for comparing said first and second control signals and assuming first and second output states dependent on the relationship between said first and second control signals; and
switch means connected to said second control means, said alternating current source and said start winding, for connecting and disconnecting said alternating current source and said start winding in response to the output state of said second control means.
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Accused Products
Abstract
A starting control circuit is provided for an alternating current motor having a run winding and a start winding and a mechanical rotational output. The motor is powered by an alternating current source. A reference oscillator produces pulses having a reference frequency. A first control circuit is provided for counting the number of reference pulses produced during a predetermined number of cycles of the alternating current source. A sensor is provided for sensing a predetermined amount of rotational movement of the mechanical rotational output of the motor and producing a sensor pulse indicative thereof. A second control circuit is provided for counting the number of reference pulses produced during the time between a predetermined number of sensor pulses and for comparing the counts on the first and second control circuits. The second control circuit assumes first and second output states dependent on the relationship between the first and second output counts. A switch is connected to the second control circuit, the alternating current source and the start winding for connecting and disconnecting the alternating current source and the start winding in response to the output state of the second control circuit.
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Citations
36 Claims
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1. A starting control circuit for an alternating current motor having a run winding and a start winding and a mechanical rotational output comprising:
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an alternating current source; reference means for producing a reference signal; first control means responsive to said reference signal and the frequency of said alternating current source for producing a first control signal; sensor means for sensing a predetermined amount of rotational movement of said mechanical rotational output and producing a sensor signal indicative thereof; second control means responsive to said reference signal and said sensor signal for producing a second control signal and for comparing said first and second control signals and assuming first and second output states dependent on the relationship between said first and second control signals; and switch means connected to said second control means, said alternating current source and said start winding, for connecting and disconnecting said alternating current source and said start winding in response to the output state of said second control means. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
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12. A digital starting control circuit for an alternating current motor having a run winding and a start winding and a mechanical rotational output comprising:
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an alternating current source; reference signal producing means for producing pulses having a reference frequency; first control means for counting the number of said reference pulses produced during a predetermined number of cycles of said alternating current source; sensor means for sensing a predetermined amount of rotational movement of said mechanical rotational output and producing sensor pulse indicative thereof; second control means for counting the number of said reference pulses produced during the time between a predetermined number of sensor pulses, and for comparing the counts in said first and second control means and assuming first and second output states dependent on the relationship between said counts; and switch means connected to said second control means, said alternating current source and said start winding for connecting and disconnecting said alternating current source and said start winding in response to the output state of said second control means. - View Dependent Claims (13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 36)
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33. A digital starting control circuit for an alternating current motor having a run winding and a start winding and a mechanical rotational output comprising:
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an alternating current source for delivering alternating current at a line frequency; reference signal producing means for producing pulses having a reference frequency; sensor means for sensing a predetermined amount of rotational movement of said mechanical rotational output and producing a sensor pulse indicative thereof; control means connected to said alternating current source, said reference signal producing means and said sensor means and operating independently of any particular line frequency and any particular reference frequency for assuming a first output state when the output speed of said mechanical rotational output is below a predetermined level and for assuming a second output state when the output speed of said mechanical rotational output exceeds said predetermined level; and switch means connected to said control means, said alternating current source and said start winding for connecting and disconnecting said alternating current source and said start winding in response to the output state of said control means. - View Dependent Claims (34, 35)
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Specification