Robert H Douthart

US Patent:

46238298, Nov 18, 1986

Filed:

Sep 7, 1984

Appl. No.:

6/648024

Inventors:

Howard W. Smith - West Carrollton OH
Robert H. Douthart - Burlington NC

Assignee:

A. O. Smith Corporation - Milwaukee WI

International Classification:

H02P 142

US Classification:

318793

Abstract:

A multiple speed motor includes first and second speed windings connected to first and second power terminals and a start winding connected to a common power terminal. A Triac connects one speed winding to power and has a gate. Either the first or second power terminal is connected to one side of a power supply and the third or common terminal is connected to the second side of the power supply. The gate is connected to the start winding. A speed responsive switch has first and second contacts connected to first and second power terminals and third connected to a common node the connection between the start winding and the gate. The speed responsive switch has a first position which all contacts are engaged to simultaneously energize the first speed winding and the start winding independent of which of power terminals is connected to the power supply and at a selected speed operates to open all contacts whereby the first and second power terminals are disconnected from each other and from said common connection of the gate and start winding. With power at the first power terminal the first speed winding is energized to establish a first speed mode of operation with power at the second power terminal. The second speed winding is energized to establish a second speed mode.

US Patent:

44437498, Apr 17, 1984

Filed:

Oct 7, 1982

Appl. No.:

6/433214

Inventors:

Robert H. Douthart - Burlington NC
Howard W. Smith - West Carrollton OH

Assignee:

A. O. Smith Corporation - Milwaukee WI

International Classification:

H02P 142

US Classification:

318774

Abstract:

An AC split-phase induction motor has a two-pole run winding, a four-pole run winding and a separate start or phase winding. The two-pole winding is connected directly to a corresponding first power terminal. The second run winding is connected to a second power terminal by a solid state gated run switch having a turn-on gate. The start winding is connected in circuit in series with a solid state gated start switch connected to the first power terminal and having a gate connected to a second power terminal. A centrifugal switch connects the first and second power terminals. The gate of the run switch is connected to the start winding circuit and includes connecting Diac and resistance elements to actuate the run switch only in response to a power connection to the second power terminal and the opening of the centrifugal switch. In operation, the motor always starts with the two-pole run winding and the start winding in the circuit. At switching speed, the start switch disconnects the start winding.

US Patent:

44672578, Aug 21, 1984

Filed:

Oct 7, 1982

Appl. No.:

6/433244

Inventors:

Robert H. Douthart - Burlington NC
Howard W. Smith - West Carrollton OH

Assignee:

A. O. Smith Corporation - Milwaukee WI

International Classification:

H02P 148

US Classification:

318774

Abstract:

An AC induction motor has a two-pole run winding connected directly to power, a four-pole run winding connected to power by a "Triac" switch, and a separate start winding connected to power by a "Triac" switch and a centrifugal start switch. The centrifugal switch is connected between a common node to the start "Triac" and either one or the other of the power terminals. The motor always starts as a two-pole start and two-pole run winding motor. Depending upon the power terminal connection, the motor continues to run with power supplied to the two-pole run winding, or actuate the "Triac" switch of the four-pole winding to operate as a four-pole motor. In different embodiments, the centrifugal switch is connected between the start circuit terminal and either the power terminal of the four-pole winding or of the two-pole winding.