Regulated high voltage,direct current power supply useable with an electrostatic coating device

Claim 2

The power supply of claim 1, wherein The trigger means is a relaxation oscillator including: a unijunction transistor having an emitter and base 1 and base 2; a resistance-capacitance timing means connected to the emitter of the unijunction transistor and to the source whereby the timing means charges causing the emitter to forward biased so as to bias the unijunction transistor to conduction; and a resistance means connected to base 1 of the unijunction transistor providing a discharge path for the charge carried by the capacitor whereby discharging of the capacitor biases the unijunction transistor to nonconduction.

Claim 3

The power supply of claim 3, wherein the oscillation frequency of the relaxation oscillator is about 1,000 cycles per second or more.

Claim 4

The power supply of claim 3, wherein the transformer includes a ferrite core.

Claim 5

The power supply of claim 3, wherein the semiconductor switch includes an SCR diode having the gate thereof connected to base 1 of the unijunction semiconductor whereby positive going pulses bias the SCR diode to conduction.

Claim 6

The power supply of claim 6, wherein the energy storage means and the winding of the transformer cooperate to force commutate the SCR diode upon about cessation of each positive going pulse.

Claim 7

The power supply of claim 7, further including NPN transistor means and relay means adapted to be actuated when the NPN transistor means is biased to conduction connected between the source of direct current and the trigger circuit, actuation of the relay means causing the trigger circuit to be connected to the source of direct current.

Claim 8

The power supply of claim 7, wherein the source of direct current includes a direct current regulator means including cascade transistors and a Zener diode connected to the base of the first one of the cascaded transistors, the Zener diode maintaining the voltage at the base of the first transistor substantially constant whereby the regulator means provides a substantially constant direct current output.

Claim 9

The power supply of claim 9, wherein the source of direct current further includes a voltage compensation means connected to direct current regulator means.

Claim 10

A high voltage, low current power supply comprising: a source of direct current including voltage compensation means and a direct current regulator means connected to the voltage compensation means, the voltage compensation means including a parallel combination of a resistor and a capacitor, a Zener diode connected in series with the parallel combination and a unijunction transistor having the emitter thereof connected to the cathode of the Zener diode whereby the parallel combination adds to the Zener voltage a direct current voltage proportional to the supply voltage which is fed to the bases of the unijunction transistor thereby regulating biasing of the unijunction transistor in accordance with the variations in the supply voltage, the regulator means including cascade transistors and a Zener diode connected to the base of the first one of the cascade transistors, the Zener diode maintaining the voltage at the base of the first transistor substantially constant whereby the regulator means provides a substantially constant direct current of output; means including a relaxation oscillator having an input connected to a source of direct current and an output, the oscillator capable of converting the direct current to a plurality of positive going substantially spaced pulses provided at the output of the oscillator, the oscillator includes a unijunction transistor having an emitter and base 1 and base 2, the pulses being taken from base 1, a resistance-capacitance timing means connected to the emitter of the unijunction transistor and to the source whereby the timing means charges causes the emitter to be forward biased so as to bias the unijunction transistor to conductor, and a resistance means connected to base 1 of the unijunction transistor providing a discharge path for the charGe carried by the capacitor whereby discharging of the capacitor biases the unijunction transistor to conduction; means including a semiconductor switch connected to the output of the oscillator whereby the application of a pulse from the oscillator biases the semiconductor switch to conduction, the semiconductor switch including an SCR diode having the gate thereof connected to base 1 of the unijunction semiconductor whereby the positive going pulse bias the SCR diode to conduction; means including an energy storage device connected to the source of direct current and adapted to be charged thereby when the semiconductor switch is nonconducting and adapted to be discharged when the semiconductor switch is conducting; and means including a transformer having one end of a winding connected to the energy storage device, the other end of the winding connected to the semiconductor switch whereby discharging of the energy storage device provides pulses to the winding of the transformer which are converted to a high voltage by the transformer, the energy storage means and the winding of the transformer cooperating to force commutate the SCR diode upon cessation of each positive going pulse.

Claim 11

The power supply of claim 11, wherein the source of direct current further includes a step-up transformer connected to a source of alternating current and a rectifying means connected to the step-up transformer for rectifying the alternating current, the rectifier means connected to the voltage compensation means so that the rectified alternating current is fed to the voltage compensation means.

Claim 13

The method of claim 13, including the further step of commutating the semiconductor switch at about the conclusion of each substantially equally spaced pulse.

Claim 14

The method of claim 14, including the further steps of, prior to the step providing a plurality pulses, converting an alternating current input signal to direct current and compensating for variations in the magnitude of the input signal whereby the plurality of substantially equally spaced pulses are provided.