WARNING SIGNAL RELAY AND SYSTEM

摘要

The switch is designed to be used in a washing machine to sense an out-of-balance condition of the tub during the spin cycle. The assembly is wired into the washer with the coil in series with the washer motor but the coil is normally shunted by a switch which is self biased to its "closed" position bridging the coil terminals. In this condition the motor operation is normal. When an out-of-balance tub in a clothes washer bumps the wand projecting from the armature the armature is moved to the core of the coil and actuates the switch plunger to open the switch, thus placing the coil in series with the motor. The relatively high impedance of the coil relative to the motor impedance limits motor current so the motor stops. The A-C supply to the coil causes the armature to vibrate (buzz) giving an audible signal that the washer has stopped due to an unbalanced load. The washer is restored to normal by opening the line switch which de-energizes the coil to thereby release the armature and permit the switch to reclose and restore the coil shunt.