摘要:
An equalizer for equalizing the charge on several series-connected cells includes a transformer having plural windings on a core corresponding to the number of cells. The windings are tightly coupled to one another. A switching device such as a MOSFET is connected to each of the windings, and a winding and a switching device are connected across each of the cells. The switching devices are simultaneously switched at a relatively high frequency, e.g., 20 Hz, and the voltage across the highest charged cell appears across each of the windings when the switching devices are on. Current flows from the most highly charged cell to a cell or to cells of lower charge, with the charging current being proportional to the difference in voltage between the highest charged cell and each of the lesser charged cells. Equalization is carried out with very little power consumption by the equalizer, allowing charging to take place in a rapid manner.
摘要:
An apparatus and method for greatly increasing power line surge/transient resistance of power semiconductors in inductive heating equipment, in which a sample of the instantaneous line voltage or its rectified equivalent is applied to a comparator input terminal, and a reference voltage corresponding to a predetermined surge shutdown voltage is applied to an opposite comparator input, such that comparator output changes state in response to the predetermined surge shutdown voltage, and is functionally connected to gate drive circuitry to disable gate drive circuitry for the duration of the surge/transient.
摘要:
The method and apparatus are for use in automotive vehicle repair, both mechanical and body. The apparatus includes at least an eddy current/hysteretic circuit and at least one applicator functionally engaged to the circuit for obtaining a desired result when the applicator is placed into contact with structure of the vehicle to be affected by heating thereof.
摘要:
A dimmer oscillator for a high frequency luminous tube power supply including a frequency shiftable high frequency oscillator, a variable duty cycle low frequency oscillator operatively connected to the high frequency oscillator for controlling the high frequency oscillator between a first normal output operating frequency and a second higher frequency. A low pass filter within the high frequency supply whereby the supply output to a luminous tube load is reduced, when the oscillator is operating at the second higher frequency, to a low intensity ionization maintenance level. An integrator between the low and high frequency oscillators whereby the transition between the first nominal and second higher operating frequencies is smoothed to reduce acoustic noise and false GFI and OVP triggering. A frequency control diode between the low and high frequency oscillators to limit the lower frequency excursion, and to maintain oscillation of, the high frequency oscillator.
摘要:
An apparatus and system for using magnetic fields to heat magnetically susceptible materials within and/or adjacent to adhesives, resins, or composites so as to reversibly or irreversibly bond, bind, or fasten opaque or non-opaque solid materials to one another. The system makes use of the effect that alternating magnetic fields induce eddy currents and generate heat within susceptors, and the effect that alternating magnetic fields additionally induce magnetic hysteresis that occurs in magnetic materials and thereby generate heat. An induction heating tool is used to emit the magnetic field at its work coil, and an electronic controller measures the energy being used by a power converter that generates the alternating current driving the work coil which creates the magnetic field. The distance between the susceptor and work coil is repeatedly analyzed based upon the power converter's input energy, and the work coil is driven at a repeatedly corrected power level during the heating cycle. Once a sufficient accumulated energy has been delivered to the susceptor, the magnetic field is turned off automatically by the tool, thus preventing overheating of the susceptor.
摘要:
Apparatus for detecting series arcs and output load faults in high frequency luminous tube power supplies and ballasts including wideband ringing and detector circuits for collecting the intense high frequency, pre-plasma noise energy associated with the initial avalanche phase of high frequency arc formation and a transient suppressor for delaying the triggering of power supply shut-down for up to the duration of the arc avalanche phase. Plural detectors for increased sensitivity and reliability over a variety of arc locations may be employed. Dual purpose detector input probes serve as over-voltage corona generators.
摘要:
A process and apparatus for testing the degree of vacuum in an evacuated vial. For testing the vacuum, a vial is located at a source of high voltage radio frequency power and the power is applied to the vial. A momentary intense flash of light is applied to the vial to cause ionization of the gas within the vial and the ionization current of the ionized gas within the vial is then sensed and a representation of the value of the ionization current is generated. The representation of the ionized current is compared with a minimum acceptable current value which is indicative of a predetermined minimum allowable vacuum within the vial. The vial is rejected if the measured ionization current is less than the minimum acceptable current value. In one embodiment, the apparatus includes a single station for testing evacuated vials, one at a time. In another embodiment of the apparatus, a plurality of vials are conveyed in a carousel through a series of testing stations. Acceptable vials continue to a downstream location, while unacceptable vials are rejected before release from the carousel.
摘要:
A vehicle disabling device is positioned under a vehicle desired to be stopped, sends a capacitive discharge therethrough, and disables at least one electric system of the vehicle.
摘要:
An analog, low-cost nickel-cadmium battery charger including a fast charging current circuit and a slow charging current circuit, both of which are controlled by a comparator circuit which compares the characteristic negative change in battery voltage at the onset of overcharge to the stored charging voltage and changes the charging current from fast charging to slow charging when the battery voltage begins to decrease at the onset of overcharge, a timer that shuts off the fast charging current circuit after a predetermined period of time and reverts to the slow charging current circuit, and a thermostat that checks the temperature of the battery and, in the event of overheating or cooling below a predetermined temperature, stops all charging of the battery.
摘要:
A low current, high voltage power supply for gas discharge devices, such as neon tubes. The power supply has a free-running oscillator which generates a high frequency voltage signal which drives a light-weight, compact transformer. The oscillator has a power transistor drive, and a second transistor is used to remove the base drive of the power transistor to render it non-conductive. The second transistor also provides a path for rapid evacuation of the charge carriers stored in the base-emitter junction of the power transistor to rapidly render it non-conductive when the second transistor is energized. A safety bypass circuit is provided should a fault occur with the gas discharge device.