Browse Prior Art Database

Transformer Motor Disclosure Number: IPCOM000095091D
Original Publication Date: 1965-Sep-01
Included in the Prior Art Database: 2005-Mar-07
Document File: 3 page(s) / 64K

Publishing Venue


Related People

Huckabee, JM: AUTHOR


A motor is provided with auxiliary windings for use in various control circuits.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 53% of the total text.

Page 1 of 3

Transformer Motor

A motor is provided with auxiliary windings for use in various control circuits.

Single-phase induction motor 1 at a has armature 2 with rotor bars 3 and shorting ring 4, as at b. Motor 1 has a number of stator poles 5 and 6, coupled by line winding 7 and auxiliary load winding 8. The flux distribution for the winding arrangement at b is shown at c.

A winding arrangement for a four-pole motor is shown at d. The output from winding to winding is automatically load balanced. This is because of the primary voltage distribution resulting from reflected reactance in the secondary windings. As an example, loading of winding 9 reflects a reduced reactance into the corresponding line winding, thus raising the voltage on windings 10, 11 and 12. Conversely, loading of winding 12 raises the voltage output on windings 9, 10 and 1 1. The output voltage from the secondary winding thus becomes self- balancing.

Drawing e depicts a two-pole motor arrangement with respective secondary windings. Winding 14 is magnetically disassociated from the other windings. It is arranged to resonate with capacitor 15 and winding 16 at a frequency of approximately 55 cycles per second when used with a 60 cycle power source. Increasing the armature load torque reflects a lower reactance into winding 16. This lower reactance causes the circuit, including windings 14 and 16 and capacitor 15, to approach resonance at 60 cycles. As the resonance range is approached, the voltage developed in winding 16 increases in proportion to the circuit impedance. Therefore, the load voltage increases as the rotor torque increases. By polarity reversal of winding 16, the output voltage can be made to decrease as the motor load torque increases. By suitable choice of the ratios of windings 16 and 17, the output voltage can be held essentially stable with reasonable excursions in applied line voltage and armature torque demands. An arrangement for multivoltage operation at f includes switch 13 for selectively determining the line voltage.

The motor line winding in g is divided into an equal number of major coils 18 and 19, and minor coils 20 and 21. Maj...