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.

Abstract: In a power inverter, ripple current and bulk filtering are provided by a high-current, high-microfarad film capacitor arrangement; there is no separate snubber capacitor section. In an alternative embodiment, a small high-frequency film capacitor is connected in parallel with the bulk film capacitor arrangement, thereby increasing the operating range of the circuit.

Abstract: The present invention provides a method and circuit for controlling the flow of current through a load. In a preferred embodiment, an oscillator generates a pulse signal of constant frequency. A pulse width modulator adjusts the duty cycle of the pulse signal in response to a dimming level signal input indicative of the desired level of current flow through the load. A converter receives the pulse signal as an input and converts it into an AC signal, the frequency of which follows the frequency of the pulse signal and the symmetry of which varies with the duty cycle of the pulse signal. The load is connected into a resonant circuit tuned such that a change in the symmetry of the AC signal changes the level of current flowing through the load.

Abstract: A preferred embodiment of the present invention provides a ballast circuit, comprising three sections: an input power section that receives a line AC signal as an input and provides a DC signal as an output; a pre-regulator section that conditions the DC signal; and a lamp driver section that drives a gas discharge lamp load. The pre-regulator section includes a transformer with an input winding, an output winding, and a current sense winding. The input winding receives the DC signal provided by the input power section. The output winding is connected in a flyback configuration with a flyback blocking diode, a bulk storage capacitor, and an output terminal for the conditioned DC signal. The current sense winding generates a signal proportional to the level of the transformer current. The transformer current is controlled by a flyback switch. A resonant capacitor is connected between the flyback switch input and ground, the resonant capacitor and the transformer forming a resonant circuit.

Abstract: The present invention provides a low-cost power factor corrected electronic ballast circuit. A preferred embodiment includes a discontinuous conduction mode boost power factor correction circuit that is controlled with a simple pulse-width modulator (PWM) circuit comprising a few discrete components instead of an integrated circuit. The PWM circuit utilizes a reference waveform signal derived from the ballast inverter. The reference waveform is combined with a feedback signal to create a composite signal that is compared with a reference voltage to create a pulse-width-modulated signal. The feedback signal is used to regulate the bulk DC voltage. In an alternative embodiment, a feedforward signal that is proportional to the time-varying level of the rectified line voltage is added to the reference waveform and the feedback signal, and serves to modulate the pulse width of the boost circuit in a manner that reduces the harmonic distortion of the input current.

Abstract: A preferred embodiment the present invention provides a system for extracting and concentrating active ingredients from herbs. The herbs are boiled in a suitable extraction medium, such as water or alcohol, in an extraction vessel. The extraction vessel is connected to a vacuum line that both serves to lower the pressure of the extraction vessel and to draw off herbal vapor formed in the boiling process. A vapor condenser cools the herbal vapor, forming an herbal condensate that is collected and periodically reintroduced into the extraction vessel, thereby lowering the density of the herbal liquid. After a predetermined period of time, a first portion of herbal liquid is transferred from the extraction vessel to a concentration tank, while the remainder of the herbal liquid continues to boil in the extraction vessel.

Abstract: One half-connector terminates a set of leads in the ballast, for carrying electrical power to and from the ballast coils. Another half-connector terminates another set of leads outside the ballast, connected e.g. to carry power to lamp sockets. Male contacts, preferably formed very inexpensively as bared ends of one set of leads, are held in a first of the half-connectors; female contacts, connected to the other set of leads, are held in a second of the two half-connectors. Through-holes in the second half-connector each hold one female contact; each hole has a necked-down section, forward from the contact, and some device (preferably an ultrasonically displaced slug) to retain the contact. In one aspect of the invention, each hole also has a bore whose transverse preformed dimension is biggest immediately rearward from the necked-down forward section.

Abstract: The present invention provides a resonant power converter for changing the magnitude of a DC voltage. The converter includes a common magnetic core with three legs (an "EE" core). The core has primary and secondary windings wound onto a first outside leg, and a tank winding and control windings wound onto a second outside leg. Control switch means are provided for effecting alternate pulses of current flow through the primary winding to effectuate alternate flux flow, the control switch means and the primary winding having a predetermined parasitic capacitance with a predetermined delay time between the termination of a given pulse and initiation of the succeeding pulse. The secondary windings are oriented to conduct alternately in phase with the alternate flux flow, there being inherent in the first leg of the transformer a magnetizing inductance, such that the magnetizing current will be great enough to charge said parasitic capacitance in a controlled fashion.

Abstract: In a rotor mounting system, a tab is welded to the outer race of a bearing assembly extending in a radial direction beyond the diameter of the outer race. The motor bracket housing includes a boss projecting upward from the housing proximate to the receiving cavity for the bearing assembly, such that when the bearing assembly is seated in the receiving cavity, interference between the tab and the boss prevents rotation of the outer race within the receiving cavity.

Abstract: An improved method is provided for the design of high-efficiency electric machines. The maximum practical value of air gap flux density B.sub.g is selected, consistent with maintaining acceptable noise and vibration levels. The value of B.sub.g selected is then used to determine the dimensions of the stator and rotor laminations so as to result in flux density levels that minimize core loss, stator I.sup.2 R and rotor I.sup.2 R losses, and magnetizing current requirements.

Abstract: The present invention provides an improved extraction process of the type in which herbs are boiled in a solvent to produce an herbal liquid that is concentrated to form an herbal extract. In a first phase of the improved process, herbs are boiled in a solvent in an extraction vessel to form an herbal liquid and an herbal vapor; the herbal vapor is drawn into a collection tank, where it is allowed to condense into an herbal condensate that is periodically re-introduced into the herbal liquid in the extraction vessel. In a second phase, a portion of the herbal liquid is drawn into a concentration vessel, where it is concentrated into herbal extract while the herbal liquid continues to boil in the extraction vessel; this second phase is repeated until there is no more herbal liquid in the extraction vessel. In a third and final phase, the last of the herbal liquid drawn into the concentration vessel from the extraction vessel is concentrated into herbal extract.

Abstract: An AC motor is provided with a motor housing and a photoelectric sensor associated with the housing. The sensor is part of a motor control circuit which is thereby responsive to the ambient light condition to control the motor by selectively switching At on and off, or alternatively by selectively switching between higher and lower speeds. The control circuit derives its power from the motor's AC input terminals, thereby yielding a self-contained motor control unit, which requires no timer unit and no wiring or mounting by the user. In accordance with another aspect of the present invention, the photoelectric sensor extends through an aperture in a motor housing end cap with the associated control circuitry fitable within the end cap, thereby providing a retrofit for existing motors.

Abstract: A soft-sided cooler is disclosed having a pivotably fastenable lid and a coolant container dimensioned to fit snugly within the underside region of the lid as defined by a plurality of generally opposing, inwardly facing sidewalls that extend downward towards the cooler body for fastening thereto when the lid is closed. The container is retained within the underside of the lid by VELCRO fastening surfaces on the container which mate with VELCRO fastening surfaces on at least a generally opposing pair of the sidewalls.

Abstract: An assembly tool helps connect an electrical external half-connector to an internal half-connector at an aperture in a ballast case. The tool includes a fulcrum for stabilizing the tool against the case, and tongue for pushing the external half-connector into engagement while clearing the connector wires, to avoid damage. A handle of the tool is used to rotate the tool about the fulcrum. If the connector has a latch to deter pull-out, the tool also preactuates or depresses the latch to eliminate frictional resistance to inserting the latch--and so reduce the required engagement force. Latch depression is simultaneous with the point in the insertion process where the latch hook passes its mating engagement member. The tool dimensions provide a high mechanical advantage to help push the two connector halves together against friction. The tool converts the connector-engaging task from wrist action to a stress-free upper-body movement.