Portable battery charging apparatus and methods therefor

• US 4,692,680 A
• Filed: 08/12/1985
• Issued: 09/08/1987
• Est. Priority Date: 08/12/1985
• Status: Expired due to Fees

• Current Assignee: GNJ Solutions, Inc.
• Original Assignee: Seacliff International, Inc.
• Inventors: Sherer, Paul
• Primary Examiner(s): Hickey, R. J.
• Application Number:
  US06/764,656
• Time in Patent Office: 757 Days
• Field of Search: 320/2-5, 320/15, 320/16, 320/35, 320/39, 320/40, 320/44, 320/48, 320/37, 320/38, 340/636
• US Class Current: 320/103
• CPC Class Codes: H02J 7/00714 in response to battery charging or discharging current
• CPC Class Codes: Y10S 320/18 Indicator or display

Abstract

Portable apparatus for charging a lead-acid battery from a direct current source such as a series of dry cells that can be conveniently carried in a motor vehicle or the like. An electronic circuit measures the actual current transferred to a battery undergoing charging and automatically signals when a preselected quantity of electric charge has been transferred to the battery undergoing charging. The electronic circuit means also signals that the battery undergoing charging has a preselected voltage level. The electronic circuit automatically signals that the direct current source has sufficient energy to charge a battery before a battery to be charged is connected thereto. The timing of the charge transfer is through the provision of charging and discharging a capacitor between preselected voltage levels by a current proportioned relative to the charging current and counting up a binary counter each time a preselected point in the oscillations are reached until a preselected count is reached.

Claims

1. Portable apparatus for charging a lead-acid battery comprising means for providing a preselected direct current voltage and current for charging a discharged lead-acid battery, said means including a plurality of dry cell batteries connected in a series circuit relationship, means for connecting said lead-acid battery to be charged in a series circuit relationship with said direct current means for transferring a pre-selected quantity of charge to the lead-acid battery, electronic circuit means coupled across said direct current means in a parallel circuit relationship with the lead-acid battery, the electronic circuit means including means for providing an electrical current signal representative of the actual current transferred to a battery being charged, means for converging said electrical current signal to a voltage control signal, voltage controlled oscillator means coupled to be responsive to the voltage control signal for controlling the oscillation cycles thereof, and electronic counting means for accumulating the oscillator cycles therein until a preselected count is reached, the preselected count being representative of the transfer of a preselected quantity of electric charge to the lead-acid battery.

2. Portable apparatus for charging a lead-acid battery as defined in claim 1 including voltage regulating means coupled across the direct current means for regulating the direct current voltage coupled to the electronic circuit means.

3. Portable apparatus for charging a lead-acid battery as defined in claim 1 wherein said plurality of dry cell batteries comprises 16 alkaline batteries arranged in a series circuit relationship.

4. Portable apparatus for charging a lead-acid battery as defined in claim 1 wherein said electronic counting means is a binary counter coupled to be counted up each time the oscillator means reaches a preselected point in each cycle of oscillation.

5. A method of charging a lead-acid battery from a battery pack including the steps of determining the number of alkaline batteries to be used for producing sufficient voltage and current to charge a chargeable, discharged lead-acid battery for transferring a preselected quantitity of electricity to a discharged battery when the individual alkaline batteries are connected in a series circuit relationship and thereby defining the power pack, applying the thus defined battery pack to a discharged battery by supplying current from the power pack in the opposite direction from he flow of current from the battery on discharge for charging the battery, continuously providing a signal representative of the charging current flowing through the battery on charging and measuring the charge transferred to the charging battery with time based on said signal, and when the measured charge transferred reaches a preselected level, automatically signaling the termination of the charging interval.

6. A method for charging a battery including the steps of providing a direct current power source comprising a plurality of batteries for providing a preselected direct current voltage and current, coupling a discharged battery to be charged to the direct current power source charging said battery to a preselected level of charge transfer, applying a current having a preselected ratio relative to the battery charging current to a capacitor to charge the capacitor to a preselected high voltage level, sensing the time that the capacitor charges to the preselected high voltage level and counting a counter up one count each time the capacitor is charged to a preselected high voltage level and then causing the capacitor to be discharged to the preselected low voltage level, sensing the time that the capacitor charges to said low voltage level and terminating the discharge of the capacitor and thereby initiating the recharging of the capacitor to said preselected high voltage level, when the counter reaches a predetermined count representative of a preselected charge transferred to the battery, automatically terminating the charging of the capacitor and signaling that the battery is charged.

16. Portable apparatus for charging a discharged lead-acid battery as defined in claim 6 wherein said signalling means is a preselected light emitting device that is connected to be energized only when said power source voltage has a preselected voltage level.

7. A method for charging a battery including the steps of providing a battery pack having a preselected output voltage and current capable of providing a charging current to the discharged battery, coupling the battery pack to an electronic circuit for measuring the transfer of electrical charge to a battery to be charged and signaling the charging status of the battery pack and the battery to be charged, the electronic circuit having a first indicator for signaling that sufficient energy is present in the battery pack to enable a battery to be charged therefrom when the electronic circuit is coupled to the battery pack so as to be powered therefrom, the electronic circuit having a second indicator for signaling that an electrical charge has been transferred to a battery undergoing charging and a third indicator for signaling when a preselected measure of electrical charge has been transferred to a battery undergoing charging for signaling the charged state of the battery, coupling a battery to be charged to the battery pack for providing a charging current to the battery and charging the battery, sensing the charging current coupled to the battery being charged at the electronic circuit for measuring the transfer of electrical charge to said battery and controlling the signaling state of the second and third indicators during the charging of the battery, and continuously charging the battery until the electronic circuit measures that the preselected measure of electrical charge has been transferred to the battery and signals the charged state by said third indicator.

8. A method of charging a lead-acid battery from a direct power power source consisting of dry cell batteries including the steps of arranging sixteen alkaline batteries in a series circuit relationship as a power pack for providing an output voltage of twenty-four volts, directly connecting a discharged lead-acid battery, capable of being charged, to the power pack for continuously transferring an electric current to the battery for recharging the battery over a preselected time interval, the preselected time interval being selected for transferring a preselected quantity of electricity to the battery, and automatically measuring the actual current transferred to the battery over said preselected time interval and automatically signaling when said preselected quantity of electricity has been transferred to the battery.

9. A method of charging a lead-acid battery from a direct current power source consisting of dry cell batteries as defined in claim 8 wherein the quantity of electricity transferred is 1/2 ampere-hour.

10. A method of charging a lead-acid battery from a direct current power source consisting of dry cell batteries as defined in claim 8 or 9 wherein the step of automatically measuring the current transfer includes the steps of sensing the charging current flowing through the battery and converting the sensed current to a voltage for controlling an oscillator and accumulating the number of oscillator cycles in an electronic counter during the preselected time interval until the preselected quantity of electricity has been transferred.

11. A method of charging a lead-acid battery from a direct current power source consisting of dry cell batteries as defined in claim 8 including the step of automatically signaling that said power pack has a sufficient quantity of charge for re-charging the battery.

12. A method of charging a lead-acid battery from a direct current power source consisting of dry cell batteries as defined in claim 11 including the step of automatically signaling the battery is being charged after it has been connected to the power pack.

13. A method of charging a lead-acid battery from a direct current power source consisting of dry cell batteries as defined in claim 12 including the step of automatically signaling a preselected voltage level at the battery during the charging thereof.

14. Portable apparatus for charging a discharged lead-acid battery comprising means for receiving a self-contained power source having a preselected voltage and current selected for charging said lead-acid battery, means for connecting said battery to be charged to receive a battery charging current from said charging power source when connected in charging circuit relationship therewith, circuit means coupled between said two mentioned means in a parallel circuit relationship with each of said means and powered from a connected self-contained power source for transferring a preselected quantity of electrical charging current between said power source and a connected battery to be charged, said circuit means including circuit means for providing an electrical current signal representative of a preselected small fraction of the battery charging current, voltage controlled, time-base oscillating signal means having a capacitor adapted to be charged and discharged for defining the oscillations thereof, means for coupling the electrical signal representative of a fraction of battery charging current to said oscillator capacitor for charging the capacitor therefrom at a charging rate in accordance with the magnitude of the battery charging current, means for sensing the voltage stored on the capacitor to determine when the voltage on the capacitor is charged to a preselected high voltage level and for terminating the charging of the capacitor when the high voltage level is reached and then causing the discharge of the capacitor, said means for sensing further sensing the voltage stored on the capacitor to determine when the voltage on the capacitor is discharged to a preselected low voltage level other than zero, and for terminating the discharge of the capacitor when the low voltage level is reached and then causing the recharging thereof, electronic, binary counting means coupled to be responsive to the capacitor being charged to said high voltage level for counting up the counter one binary bit each time the capacitor is charged to said high voltage upon the actuation of the counting means, the capacity of the counter being selected to correspond to the transfer of a preselected charge to said battery being charged so that when the preselected count of the counter is fully counted up, the battery is charged with said preselected charge, means for sensing the initiation of the battery charging to activate the binary counting means and thereby commence the battery charging timing cycle, and circuit means coupled to be responsive to the counter signalling the preselected count for terminating the charging of the capacitor.

15. Portable apparatus for charging a discharged lead-acid battery as defined in claim 14 including means for connecting and disconnecting the circuit means to said first mentioned means for powering the circuit means therefrom when said power source is connected to said first mentioned means, said circuit means including means for signalling that said connected power source has sufficient energy for charging said battery when the power source is connected and the discharged battery is disconnected from said circuit means.

17. Portable apparatus for charging a discharged lead-acid battery as defined in claim 14 or 15 including means for signalling that a preselected charge has been transferred to a battery undergoing charging.

18. Portable apparatus for charging a discharged lead-acid battery as defined in claim 15 wherein means for signalling the energy of the power source automatically signals that thevoltage of said battery undergoing charging has a preselected voltage level when the discharged battery is connected to the power source.

19. Portable apparatus for charging a discharged lead-acid battery as defined in claim 15 wherein each of the signalling means comprises light emitting diodes emitting light rays of different colors.

20. Portable apparatus for charging a discharged lead-acid battery as defined in claim 19 wherein the signalling means comprises three light emitting diodes.