US4992709A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Switching circuit providing adjustable capacitive series voltage dropping circuit with a fractional horsepower motor
Assignee: Genlyte Thomas Group LLC
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Filing: 1989-06-20
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Granted: 1991-02-12
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Expires: 2009-06-20
Abstract
Abstract A control circuit for a fractional horsepower fan motor connected between hot and neutral wires in and AC circuit is shown. The control circuit includes two or more duplicate branches. Each branch is serially connected, and each branch includes a triac, series resistor and series capacitor. The triac has a gate terminal which is connected to an optical coupling circuit for isolation and responds to a control signal from a low voltage small current source. In an alternative embodiment, a single triac and optical coupling circuit can be used with different capacitors being switched in or out of the circuit.
Inventors
- 👤 Raymond T. Griffin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 18:15
CPC Classifications
H; H02; H02P; H02P25/00; H02P25/02; H02P25/04
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
146 words
For use in combination with a fractional horsepower alternating current motor connected between hot and neutral wires to impose a series impedance reducing the voltage applied to the motor, a motor control system which comprises: (a) at least two independent parallel capacitors connected in series with a motor and connected in series with the hot wire for conducting alternating current power to the motor; (b) first and second switching devices, each thereof being connected in series with one of said capacitors, wherein said switching devices conduct alternating current flowing between the hot and neutral wires and are controllably switched between off and on states to thereby control alternating current flow through the respectively connected capacitors; and (c) control means connected to said switching devices for providing control signals to said switching devices to selectively switch said switching devices to the on state and the off state.
Claim 2
Dependent Claim
146 words
For use in combination with a fractional horsepower alternating current motor connected between hot and neutral wires to impose a series impedance reducing the voltage applied to the motor, a motor control system which comprises: (a) at least two independent parallel capacitors connected in series with a motor and connected in series with the hot wire for conducting alternating current power to the motor; (b) first and second switching devices, each thereof being connected in series with one of said capacitors, wherein said switching devices conduct alternating current flowing between the hot and neutral wires and are controllably switched between off and on states to thereby control alternating current flow through the respectively connected capacitors; and (c) control means connected to said switching devices for providing control signals to said switching devices to selectively switch said switching devices to the on state and the off state.
Claim 3
Dependent Claim
13 words
The apparatus of claim 1 wherein said switching devices are solid state devices.
Claim 4
Dependent Claim
12 words
The apparatus of claim 2 wherein said solid state devices are triacs.
Claim 5
Dependent Claim
19 words
The apparatus of claim 3 wherein said triacs are connected so that a single triac switches a single capacitor.
Claim 6
Dependent Claim
16 words
The apparatus of claim 1 wherein said capacitors have capacitance in the ratio of about 1:2.
Claim 7
Dependent Claim
35 words
The apparatus of claim 1 wherein said switching devices are solid state circuit components having control terminals thereon, and said control means includes circuits which have infinite input impedance between the input and output thereof.
Claim 8
Dependent Claim
12 words
The apparatus of claim 6 wherein said circuits are optical coupling circuits.
Claim 9
Dependent Claim
24 words
The apparatus of claim 7 wherein said optical circuits connect with a switched DC voltage source of relatively low voltage and relative small current.
Claim 10
Dependent Claim
16 words
The apparatus of claim 8 including a series resistor connected serially with each of said capacitors.
Claim 11
Dependent Claim
16 words
The apparatus of claim 1 including a series resistor connected serially with each of said capacitors.
Claim 12
Dependent Claim
20 words
The apparatus of claim 10 wherein said solid state devices are triacs having control gates connected to said control means.
Claim 13
Dependent Claim
13 words
The apparatus of claim 11 wherein said control means include infinite input circuits.
Claim 14
Dependent Claim
29 words
The apparatus of claim 1 wherein said control means may be triggered from two separate locations by triggering means for the providing of control signals to said switching devices.
Claim 15
Independent Claim
134 words
An apparatus for varying impedance to a small alternating current motor, such as a fan motor, to vary speed of the small motor when the small motor is connected to a source of alternating current power comprising: first switching means for connecting said source of power therethrough to said small motor; second switching means for connecting between at least two different paths, said second switching means being connected between said small motor and said source of power; first capacitor means in at least one of said different paths for increasing impedance therethrough to decrease the speed of said small motor when said second switching means selects the path including the first capacitor means; and control means operatively connected to said first switching means for providing a control signal to operate said first switching means.
Claim 16
Independent Claim
134 words
An apparatus for varying impedance to a small alternating current motor, such as a fan motor, to vary speed of the small motor when the small motor is connected to a source of alternating current power comprising: first switching means for connecting said source of power therethrough to said small motor; second switching means for connecting between at least two different paths, said second switching means being connected between said small motor and said source of power; first capacitor means in at least one of said different paths for increasing impedance therethrough to decrease the speed of said small motor when said second switching means selects the path including the first capacitor means; and control means operatively connected to said first switching means for providing a control signal to operate said first switching means.
Claim 17
Dependent Claim
58 words
The apparatus as recited in claim 14 wherein there are at least three said different paths provided by said second switching means, each of said different parallel paths having a different impedance provided by at least said first capacitor means and second capacitor means being switched in and out between said small motor and said source of power.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-02-11 | 1994-08-13 | 1995-02-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-02-11 | 1998-08-13 | 1999-02-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-02-11 | 2002-08-13 | 2003-02-12 | $7700.00 | Window Closed / Lapsed |