Abstract: A dynamoelectric machine support frame wherein the stator mounting surfaces and the rotor bearing bracket mounting surfaces are all horizontally disposed in parallel planes. Further, in the preferred embodiment, all mounting surfaces on one lateral side of the frame are axially aligned with one another.

Abstract: A twin electric motor drive for a grinding mill has substantially identical synchronous motors mechanically connected to the drive of the mill, and the stator winding which generates a revolving magnetic field in each motor comprises a plurality of phase windings each of which is energized from a separate phase of a polyphase power source and has first and second winding sections which are interconnected with the second and first winding sections respectively of the corresponding phase winding of the other motor to equalize the load between the motors.

Abstract: A heating system within a high pressure gas enclosure which includes a heat emission block surrounded by an insulating tube to form a forced flow convection pump; temperature probes within the high pressure gas enclosure are located so that they will not be influenced by the operation of the heaters.

Abstract: A tap changer voltage regulator permits a tap changer switch selector contact to engage an open circuited new tap without arcing and has a half-tap voltage auxiliary winding which permits halving the voltage being interrupted and doubling the number of steps and also has an auxiliary switch with a first movable contact which initially connects the selector contact on the new tap in series with a circulating current limiting inductor and the load to prevent load circuit interruption and is provided with a second movable contact in series with a pair of normally closed contacts through which flow the load current and the current which circulates while the selector contacts bridge adjacent taps during the tap change. The normally closed contacts are shunted by a pair of inverse parallel thyristors.

Abstract: An air disconnect switch incorporates a unique arrangement of an ice breaking self-polishing current transfer horn arrangement which transfers the current to a puffer-type interrupter to effect circuit interruption prior to the disconnect switch being fully opened; the puffer-type interrupter is a dielectric insulated device which has its operating mechanism disposed within the dielectric insulating medium so that the system has no fast-moving external parts and provides a direct drive with minimum maintenance of the mechanism parts. The porcelain tube serves both as the interrupter housing and as the mechanism housing.