CAPACITOR DISCHARGE BATTERY CHARGER

• US 3,594,627 A
• Filed: 10/20/1969
• Issued: 07/20/1971
• Est. Priority Date: 10/20/1969
• Status: Expired due to Term

• Current Assignee: John C. Lesher
• Original Assignee: John C. Lesher
• Inventors: Lesher, John C.
• Application Number:
  US04/867,679
• Time in Patent Office: 638 Days
• US Class Current: 320/103
• CPC Class Codes: H02J 2207/20 Charging or discharging characterised by the power electronics converter
• CPC Class Codes: H02J 7/02 for charging batteries from ac mains by converters
• CPC Class Codes: Y10S 320/22 Line impedance, e.g. resistor
• CPC Class Codes: Y10S 320/23 Capacitor

Abstract

A capacitor discharge charger for charging a battery comprising: a capacitor electrically connected intermediate a source of power and the battery to be charged, a source of power for charging the capacitor, and means for alternately charging the capacitor from said power source and discharging it to the battery and therefore to charge said battery.

Claims

1. A capacitor discharge charger for charging a battery comprising:

a capacitor electrically connected intermediate a source of power and the battery to be charged, a source of power for charging said capacitor, means for alternately charging said capacitor from said power source and discharging it to said battery and therefore to charge said battery, a resonant feedback oscillator circuit and a transformer electrically connected intermediate said source of power and said capacitor whereby a low current may be maintained to charge said capacitor, said charging and discharging means including a unijunction transistor timing circuit for determining when said capacitor has reached a predetermined charge, and a saturated switching circuit for discharging said capacitor to said battery when said capacitor has reached its predetermined charge, said unijunction transistor timing circuit and switching circuit being electrically connected intermediate said capacitor and said battery whereby the discharge to said battery is of greater magnitude than the charge to said capacitor.

2. A capacitor discharge charger for charging a battery comprising:

a capacitor electrically connected intermediate a source of power and the battery to be charged, a source of power for charging said capacitor, means for alternately charging said capacitor from said power source and discharging it to said battery and therefore to charge said battery, said charging and discharging means including a unijunction transistor timing circuit for determining when said capacitor has reached a predetermined charge, and a saturated switching circuit for discharging said capacitor to said battery when said capacitor has reached its predetermined charge, said unijunction transistor timing circuit and switching circuit being electrically connected intermediate said capacitor and said battery whereby the discharge to said battery is of greater magnitude than the charge of said capacitor.

3. A capacitor discharge charger according to claim 1 wherein said unijunction transistor circuit includes a second capacitor connected across the first capacitor and a unijunction transistor means connected intermediate said second capacitor and said switching circuit whereby said second capacitor charges in the same manner as said first capacitor and discharges a current signal through said unijunction transistor means to said switching circuit for allowing said first capacitor to discharge to said battery.

4. A capacitor discharge charger according to claim 3 wherein said switching circuit includes a first transistor electrically connected to said unijunction transistor means for receiving said discharge signal and a second transistor electrically connected to said first transistor whereby said second transistor becomes fully conductive allowing said first capacitor to discharge to the battery when said first transistor receives said signal.

5. A capacitor discharge charger for charging a battery comprising:

a capacitor electrically connected intermediate a source of power and the battery being charged, a source of power for charging said capacitor and means for alternately charging said capacitor from said power source and discharging it to said battery and therefore to charge said battery, said last-mentioned means including a unijunction transistor timing circuit for determining when said capacitor has reached a predetermined charge and a saturated switching circuit for discharging said capacitor to said battery when said capacitor has reached its predetermined Charge, said unijunction transistor timing circuit and switching circuit being electrically connected intermediate said capacitor and said battery whereby the discharge to said battery is of greater magnitude than the charge to said capacitor, said unijunction transistor circuit including a second capacitor connected across the first-mentioned capacitor and a unijunction transistor means connected intermediate said second capacitor and said switching circuit whereby said second capacitor charges in the same manner as said first capacitor and discharges a current signal through said unijunction transistor means and said switching circuit for allowing said first capacitor to discharge to said first battery and said switching circuit includes a first transistor electrically connected to said unijunction transistor means for receiving said discharge signal and a second transistor electrically connected to said first transistor whereby said second transistor becomes fully conductive allowing said first capacitor to discharge to the battery when said first transistor receives said signal.

6. The method of charging a battery comprising the steps of supplying a low current to a capacitor for a period of time to charge said capacitor substantially to a predetermined potential, discharging a higher current from said capacitor to the battery to be charged at a predetermined point in time when the capacitor has substantially reached its predetermined charge and over a shorter period of time than required to charge said capacitor, said method further including the step of charging a second capacitor in the same manner as the first capacitor and discharging a current signal from said second capacitor to a switching circuit and thereby to discharge said capacitor through said switching circuit to said battery at said predetermined point of time.

7. A capacitor discharge battery charger comprising a capacitor, means for charging a capacitor from a source of power at a predetermined relatively low rate, an output circuit connected to said capacitor and adapted to be connected to a battery to be charged and including a controlled electronic switch is circuit with said capacitor and having a control element for holding said switch off or for turning it on to discharge said capacitor at a relatively high rate to a battery to be charged, and a timing circuit connected in circuit with said capacitor and to said control element for turning said electronic switch on when said capacitor substantially reaches a predetermined potential.

8. A battery charger as set forth in claim 7 wherein the timing circuit comprises a resistance-capacitance timing circuit.

9. A battery charger as set forth in claim 8 wherein said output circuit further includes an electronic switch device connected to said resistance-capacitance timing circuit and to the control element of said controlled electronic switch.

10. A battery charger as set forth in claim 7 wherein the means for charging the capacitor comprises a two-element rectifying device.

11. A battery charger as set forth in claim 7 and further including a source of power comprising a battery, an oscillator connected to and powered by said battery, and a rectifier interconnecting said oscillator circuit and said capacitor.