Abstract: A vacuum cleaner for simultaneously cleaning and sterilizing a surface includes a vacuum cleaner housing, a plurality of wheels for supporting the vacuum cleaner housing on the surface, a main power switch for electrically connecting the vacuum cleaner to an external source of power, a motor coupled to the main power switch and a rotary brush coupled to the motor. The motor includes a suction fan. A UV lamp housing assembly is mounted inside the vacuum cleaner housing and urged downward toward the surface. The UV lamp assembly includes a UV lamp for sterilizing the surface at the same time as it is being cleaned. A UV light gasket assembly is fixedly mounted underneath the UV lamp assembly and includes a track of conductive material having a plurality of gaps and a plurality of interlock switches for closing the gaps, one interlock switch being associated with each gap. Each interlock switch includes a cap and an interlock contact of conductive material which is fixed to the cap.

Abstract: An electronic circuit for automatically adjusting the operating point of an audio amplifier comprising means for sensing the current flowing in the load, coupled to a first threshold detector, said first threshold detector having a plurality of outputs, each of said outputs representing some fraction of maximum load current; a plurality of timing means, each triggered by one of the plurality of outputs from said first threshold detector, each having a time constant inversely proportional to the fraction of load current represented; means for sensing the operating temperature of the amplifier output stage devices, coupled to a second threshold detector, said second threshold detector having an output which is enabled above a certain temperature and where said output may be used to inhibit one or more of the timer means; means for detecting bias level in a pre-driver stage, coupled to a low pass filter; a error amplifier, whose inputs are coupled to said temperature sense means, said timer outputs and said low