Abstract: A Class-D audio amplifier is disclosed which accepts a digitized audio signal input and drives a load such as a loudspeaker without digital-to-analog conversion. The amplifier preferably comprises (1) means for processing a plurality of digital audio input values to create a plurality of deviation values respectively based on the deviation of the input value's relationship from a previous audio input value, (2) means for producing a carrier signal, (3) modulation means for using the deviation values to responsively modulate the carrier signal by varying the frequency of its waveform inversely with the magnitudes of the deviation values, and (4) filter means operative on the modulated carrier to produce an analog voltage capable of driving the load.

Abstract: A tissue dispenser is disclosed which permits a user to choose from a variety of liquids to be sprayed on a tissue prior to dispensing. To prevent the tissue from dissolving or becomes too wet to handle comfortably, the dispenser folds the tissue into a double layered structure prior to spraying with the selected liquid, and sprays one layer of the two-layer structure just prior to dispensing so that the dry layer can support the paper's shape and enable the user to handle the tissue without tearing it.

Abstract: A submersible pump is disclosed for use in a body of liquid such as a well or sump. The pump has an air intake port and an air outlet port, as well as a liquid intake port and a liquid discharge tube. A valve mounted within the pump selectively permits the pump's chamber to communicate with either the air intake port or the air discharge port. When liquid enters the pump's chamber, the air displaced by the incoming liquid is permitted by the valve to escape via the air outlet port. When the pump's chamber is sufficiently full of liquid, the valve closes off the air outlet port and permits compressed air to enter the pump's chamber via the air inlet port in order to force the accumulated liquid out the liquid discharge tube. A float in the pump's chamber rises and falls with the level of liquid in the chamber to actuate the valve.

Abstract: A DC-to-DC converter, comprising: inverter means for receiving a DC input and providing as an output a high-frequency, alternately pulsed current waveform; a control winding for receiving the output of the inverter means, the control winding being wound on a common bobbin with first and second tank windings, the windings de-coupled on the bobbin so that there is a significant leakage inductance between the windings, the first and second tank windings having two discrete resonant frequencies on a common core and flux path, a main primary winding wound in series with the control winding, the main primary winding being wound onto a separate bobbin and residing on its own core leg and flux path, first and second secondary windings coupled with the main primary winding, the first and second secondary windings being wound out of phase with each other, the first and second secondary windings feeding, respectively, first and second diodes, the first and second diodes rectifying the alternately pulse current waveform

Abstract: A submersible pump is disclosed for use in a body of liquid such as a well or sump. The pump has an air intake port and an air outlet port, as well as a liquid intake port and a liquid discharge tube. A valve mounted within the pump selectively permits the pump's chamber to communicate with either the air intake port or the air discharge port. When liquid enters the pump's chamber, the air displaced by the incoming liquid is permitted by the valve to escape via the air outlet port. When the pump's chamber is sufficiently full of liquid, the valve closes off the air outlet port and permits compressed air to enter the pump's chamber via the air inlet port in order to force the accumulated liquid out the liquid discharge tube. A float in the pump's chamber rises and falls with the level of liquid in the chamber to actuate the valve.

Abstract: A new circuit for the operation of gas discharge lamps via a converter that operates directly off the rectified AC line without reactive filtering and consequently maintains good power factor and low total harmonic distortion while still maintaining an acceptable lamp current crest factor. The converter employs active crest factor correction to control the actual lamp current to a determined peak to RMS value. The design comprises two stages: a first stage with a non-linear input voltage to lamp current transfer function and a second stage having a frequency modulation to lamp current transfer function designed to cancel the first stage's transfer function at a predetermined input voltage and thus maintain constant lamp current during the correction interval.