Abstract: An appliance is provided. The appliance includes a cabinet that defines an air passage. An air handler has an impeller that is positioned proximate the air passage. The appliance also includes features for determining whether the impeller is rotating. When the impeller rotates, the impeller draws a flow of air through the air passage.

Abstract: The synchronous motors are controlled by a three-phase AC power controller. According to an embodiment of the invention, firing points for the AC power controller are determined. A pair of two or three phases is determined from the angular position of the rotor, for which the firing points can be present for the respective A.C power controller. Actual firing points are determined from the mains voltage phase position of the phases so that only positive torque is produced.

Abstract: In a method for synchronizing drive units, a target value of the speed of each drive unit of a plurality of drive units speed is computed by determining the product of a maximum speed of the drive unit, a unit-dependent normalized ratio value of the drive unit, and a synchronization factor which is identical for all drive units. The ratio value defines the relative speeds of the individual drive units. Changing the synchronization factor causes synchronous speed changes of the drive units. As a result, a lasting synchronization can be realized across the entire speed spectrum.

Abstract: An improved technique is disclosed for adjusting the crankshaft angle of each of a plurality of synchronized tandem-coupled presses with respect to a reference shaft angle. At the start of adjustment, a plurality of first motors that synchronously drive the successive crankshafts during normal press operation are disengaged from the crankshafts and maintained operative with undiminished speed. A plurality of second motors operative at a speed slightly greater than the speed of the reference shaft are thereafter enabled when the angular phase of each crankshaft relative to that of the reference shaft is within a prescribed angular range. Such range is established by means of a synchro-driven control system coupled to the reference shaft and to the crankshaft when the first motor is disengaged from the crankshaft. Once the required angular adjustment is completed, the rotating first motor may be reengaged to the crankshaft to restore normal press operation.