United States Patent (19)
`Marek
`
`US005371454A
`[11] Patent Number:
`(45) Date of Patent:
`
`5,371,454
`Dec. 6, 1994
`
`54 PASSIVE BATTERY CHARGING SYSTEM
`76) Inventor: Albert Marek, 705 Bradley Cir.,
`Grand Prairie, Tex. 75051
`21) Appl. No.: 27,406
`22 Filed:
`Mar. 8, 1993
`51 Int. Cl. ................................................ HO2J 7/10
`52 U.S. C. .......................................... 320/15; 320/2;
`320/57
`58) Field of Search .......................... 320/15, 17, 57, 2
`56)
`References Cited
`U.S. PATENT DOCUMENTS
`3,579,075 5/1971 Floyd ...................................... 320/2
`4,092,580 5/1978 Prinze ...
`-----
`4,575,670 3/1986 Hignutt......
`4,831,321 5/1989 Cooper ............................... 320/2 X
`OTHER PUBLICATIONS
`"Dual Pro Charger', Charging Systems International,
`Advertising Letter and flossy flyer Jan., 1991.
`"Keep Car and Boat Batteries Charged When Not in
`Use-Safety”, Herrington Catalog, Valentine Ed., p.
`17, 1993.
`Primary Examiner-Robert J. Hickey
`
`Attorney, Agent, or Firm-Michael A. O'Neil
`57
`ABSTRACT
`A battery charger for simultaneously slow charging and
`thereafter maintaining a charge in a plurality of plate
`type batteries includes a first transformer connected
`through a circuit loop to a first battery wherein the
`circuit loop includes a rectifier, and a current limiter
`and visual indicator of the charge level of the battery. A
`second transformer is connected through another cir
`cuit loop to one battery and through a third circuit loop
`to a second battery. The circuit loop of the first trans
`former may be connected to a first battery with one of
`the circuit loops of the second transformer being con
`nected to a second battery connected in series to the
`first battery thus allowing the two loops to remain iso
`lated from each other and allow for charging of the
`series connected batteries without removal of the series
`connection. In a second embodiment of the invention, a
`switch is connected in the loop to bypass the current
`limiter to allow a fast charge condition. A small indica
`tor light is connected to the switch to indicate a fast
`charge condition. Thus, the charger may be switched
`from a slow passive charge condition to a fast charge
`condition, and back to a slow charge condition.
`
`14 Claims, 5 Drawing Sheets
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`U.S . PateIIt
`U.S. Patent
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`Dec. 6, 1994
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`1.
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`PASSIVE BATTERY CHARGING SYSTEM
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`TECHNICAL FIELD
`This invention relates to battery chargers, and in
`particular, to a system for charging and maintaining
`charge in an infrequently used battery.
`BACKGROUND OF THE INVENTION
`Batteries in seasonal vehicles such as boats, farm
`equipment, RVs, in some military equipment, antique
`cars, and other vehicles used infrequently or only sea
`Sonally tend to lose their charge, requiring recharging
`at various use intervals. Conventional fast battery char
`gers are large and cumbersome, use a substantial
`15
`amount of electricity, and charge at a faster rate than
`the battery can accept. When being charged with a
`conventional fast charger, the voltage and amperage of
`the battery will typically rise at a faster rate than the
`battery potential. Thus, when the voltage and amperage
`20
`reach a level indicating that the battery is fully charged,
`the battery charger will be disconnected or turned off.
`The battery will then begin to equalize the voltage,
`amperage and potential, with the voltage and amperage
`levels dropping and the potential increasing until equal
`25
`ization is reached. Because of the variation in the volt
`age, amperage, and potential levels at the time full
`charge is indicated, the battery will actually be charged
`to only about 80% of its capacity following equaliza
`tion. Thus, the prior art fast chargers cannot charge a
`30
`battery to 100% of its capacity.
`Batteries repeatedly charged in this fashion reduces
`the capacity of the battery such that the battery will
`begin to lose the ability to accept a full 100% charge of
`the original capacity. Additionally, the use of a fast 35
`battery charger often causes rapid expansion of the
`battery fluid and the generation of gases, thus requiring
`the removal of the battery caps while charging the
`battery. Failure to remove the caps may result in explo
`sion of the caps causing damage or total destruction of 40
`the battery. Thus, marine, recreational vehicle, and
`other infrequently used batteries are protected under
`substantially shorter warranty periods, often less than
`one-half the length of the warranty periods for regu
`larly used batteries, such as car batteries.
`45
`Trickle chargers, another conventional type battery
`charger, are slow battery chargers, charging the battery
`with only one-to-three amps of charge at a time. A slow
`charge will bring the battery to full charge and allevi
`ates having to remove the battery caps while charging. 50
`However, if left on the battery for an extended length of
`time after the battery has obtained full charge, the
`trickle charger will damage the battery and may de
`stroy it completely.
`Due to the slow rate at which the trickle charger
`55
`charges the battery, the charger must be connected to
`the battery a substantial period of time prior to the use
`of the boat or vehicle, prohibiting spontaneous use
`thereof.
`In one attempt to overcome the foregoing problems,
`fast and slow battery chargers were designed to include
`built in features for automatic turn off of the charger
`once the voltage of the battery indicated a full charge.
`In such chargers, once the voltage drops to a predeter
`mined level, the charger is automatically turned back on
`65
`to again recharge the battery until the voltage reaches
`the full charge level. Although the battery is automati
`cally recharged, this cycling process reduces the life of
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`the battery. Depending upon the cycling range of the
`particular charger, the user may decide to use the vehi
`cle at a point where the voltage of the battery has
`dropped to a level where the charger is about to begin
`recharging the battery.
`Many fishing boats have a driving battery and two
`12-volt batteries connected as a 24-volt power source
`for operation of a trolling motor. Thus, three chargers
`were required for charging each of the three batteries
`simultaneously.
`SUMMARY OF THE INVENTION
`The passive battery charger of the present invention
`overcomes the foregoing and other problems associated
`with prior art battery chargers by utilizing a continuous
`slow charge process, along with the capability of charg
`ing multiple batteries at the same time. A first embodi
`ment battery charger includes at least two 12-volt trans
`formers each connected in a circuit to at least one posi
`tive and one negative battery cable or terminal, with a
`light bulb connected in the circuit to regulate the am
`perage of the charging current flowing from the trans
`former to the battery. The light bulb further visually
`indicates the status of the charge on the battery in that
`the brightness of the light is inversely proportional to
`the battery charge. The circuit is further configured to
`prevent sparks when the charger is hooked up to the
`battery in reverse position or when the cables acciden
`tally come into contact with one another. When the
`cables are connected in reverse position to the battery,
`the light bulb in the circuit is brightly illuminated. On
`the other hand, the bulb is dimly illuminated when the
`cables are properly connected to the battery.
`The flow of current in the circuit from the trans
`former is reduced as the resistance of the battery in
`creases with the increased charge. As the battery
`reaches a full charge, the resistance of the battery is
`balanced with a maximum output of the transformer.
`The light bulb in the circuit line regulates the amperage
`of current flowing from the transformer to the battery
`as it is charged. The light bulb further allows for the
`back down of current produced by the transformer as a
`result of the increased resistance from the battery dur
`ing charging. Thus, the charger may remain continu
`ously connected to the battery without reducing the life
`of the battery through cycling or overcharging, and
`without damage to the transformer. Due to the low
`amperage charging process, the battery charger uses
`very little electricity, resulting in very low operational
`COStS.
`In fishing boats wherein the trolling motor is pow
`ered by two 12-volt batteries connected in series to
`provide 24-volts, the battery charger of the present
`invention allows each 12-volt battery in the 12/24-volt
`configuration to be charged at the same time without
`removing the series connection between the two batter
`ies. By providing at least two transformers, there is
`capacity for charging the driving battery for the boat at
`the same time as the trolling batteries. One transformer
`is connected through a split circuit to two sets of bat
`tery cables. The set of cables is connected to the driving
`battery with the second set of cables connected to one
`of the 12-volt trolling batteries. The remaining 12-volt
`trolling battery is connected to the cables from the
`second transformer. Thus, the circuits for charging the
`series connected batteries are isolated from one another
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`4.
`to allow charging operations without requiring removal
`connected to a battery cable 34, in turn selectively con
`nected at its distal end to the positive post of a 12-volt
`of the series connection.
`battery 36. The negative post of battery 36 is selectively
`In the event a battery must be charged in a relatively
`connected through a battery cable 38 to the anode of
`short period of time, in a second embodiment of the
`invention, a manual switch is connected to bypass the 5
`rectifier diode 40, the cathode of which is connected to
`light bulb in the circuit, thereby allowing the flow of
`a one and one-half amp light bulb 42, which functions as
`higher voltage and amperage to the battery for a fast
`a current limiter in the circuit 44. Although in the pre
`charge. An indicator light is connected to the switch to
`ferred embodiment of the invention the current in the
`indicate a fast charge condition. When the switch is in
`circuit is limited by the one and one-half amp lightbulb,
`the off position, the passive slow charge condition re- 10
`other conventional current limiters may be used in place
`thereof. To complete the circuit, light bulb 42 is con
`Sunes to maintain charge. Thus, in addition to the low
`operational costs and the continuous low amperage
`nected through line 46 to the bottom of secondary coil
`multiple battery charging capabilities, the charger may
`28.
`be converted to a fast charge device for charging of the
`When charging a second battery 48, the current from
`battery in a few hours.
`transformer 22 is split between the first circuit 44 and a
`second circuit 50. The top side of the secondary coil 28
`BRIEF DESCRIPTION OF THE DRAWINGS
`is connected through line 30 to the anode of diode 52,
`For a more complete understanding of the present
`the cathode end of which being selectively connected
`to the positive post of the battery 48 through a battery
`invention and the advantages thereof, reference is now
`made to the following Detailed Description taken in
`cable 54. The negative post of the battery 48 is selec
`conjunction with the accompanying Drawings in
`tively connected through a battery cable 56 to the
`which:
`anode of a diode 58, the cathode end of which is con
`FIG. 1 is an electrical schematic of a battery charger
`nected to a second one and one-half amp light bulb 60,
`incorporating a first embodiment passive battery char
`functioning as a current limiter for the second circuit 50.
`ger of the present invention;
`To complete the circuit 50, the light bulb 60 is con
`25
`FIG. 2 is a drawing showing an obtuse view of the
`nected to the bottom of the secondary coil 28 of first
`housing, and cables of the battery charger of FIG. 1;
`transformer 22 through lines 62 and 46.
`FIG. 3 is a drawing similar to FIG.2 with the top half
`As further illustrated in FIG. 1, the second trans
`of the housing removed to show the interior of the
`former 26 is a conventional 12-volt/1.5 amp trans
`battery charger of FIG. 1;
`former, having a primary coil 24 and a secondary coil
`30
`FIG. 4 is a side view of the battery charger of FIG.3;
`64. The top of secondary coil 64 is connected through
`FIG. 5 is a drawing of the circuit board showing the
`line 66 to the anode of a diode 68, with the cathode end
`wiring connections for the battery charger of FIG. 1;
`selectively connected through battery cable 70 to the
`FIG. 6 is a rear view of the housing of FIG. 1;
`positive post of a third 12-volt battery 72, which may be
`FIG. 7 is a top view of a boat, illustrating the posi
`a single battery or may be tied in series to battery 48 as
`35
`tioning of and the charging of the trolling motor and
`illustrated by dotted line 49 to provide a 24-volt battery.
`The negative post of the battery 72 is selectively con
`driving motor batteries;
`FIG. 8 is an obtuse view of a mounting bracket for
`nected through battery cable 74 to the anode of a diode
`mounting the battery charger to a receiving surface;
`76, the cathode end of which is connected to a third one
`FIG. 9 is a schematic circuit diagram for a battery
`and one-half amp light bulb 78, thereby limiting the
`charger incorporating a second embodiment of the pres
`current flowing through the circuit 80 to the battery 72
`to a maximum of one and one-half amps. To complete
`ent invention;
`FIG. 10 is an obtuse view of the housing of the bat
`the circuit 80, the light bulb 78 is connected through
`tery charger of FIG. 9;
`line 82 to the bottom of the secondary coil 64 of the
`transformer 26. When charging a single battery or three
`FIG. 11 is a view similar to FIG. 10 with the top of 45
`the housing removed to show the interior of the battery
`separate batteries, any one or combination of the cir
`charger of FIG. 9; and
`cuits 44, 50, or 80 may be used.
`FIG. 12 is a side view of the battery charger of FIG.
`Referring now to FIGS. 2, 3, and 4, the transformers
`22 and 26 along with the components of circuits 44, 50
`11.
`and 80 are mounted within a housing 90, having a first
`half 92 and second half 94. The first half 92 defines atop
`96, a first side 98, and a second side 100. The second half
`forms a bottom 102, a third side 104, and a fourth side
`106. In the first and second sides 98 and 100, respec
`tively, are vents 108 to allow air circulation through the
`battery charger 10. In the third side 104 are windows
`110 for observing the illumination of the lightbulbs 42,
`60, and 78. The first half 92 of the housing is attached to
`the second half 94 of the housing using conventional
`fasteners 112.
`Referring now to FIGS. 2, 3, and 6, battery cables 70
`and 74 from circuit 80 and battery cables 54 and 56 from
`circuit 50 exit the housing 90 through opening 120 in the
`fourth side 106 of the housing 90. Battery cables 70 and
`74 are paired with battery cables 54 and 56 to facilitate
`connection of the two pairs of cables to a pair of 12-volt
`batteries cross-connected for generation of 24-volts.
`Battery cables 34 and 38 from circuit 44 pass through
`
`DETALED DESCRIPTION
`Referring now to the Drawings and more particu
`larly to FIG. 1 thereof, there is shown a schematic
`diagram of the electrical circuit of a battery charger 10
`incorporating a first embodiment passive battery char
`55
`ger of the present invention for charging 12-volt, acid
`or jell, regular or deep, cycle batteries. As illustrated in
`FIG. 1, the battery charger 10 is equipped with a con
`ventional AC plug 12 insertable into a 120-volt AC
`receptacle and having opposite prongs 14 and 16 and a 60
`ground prong 18. The opposite AC prongs 14 and 16
`are connected to the opposite ends of the primary coil
`20 of a first transformer 22, and to the opposite ends of
`the primary coil 24 of a second transformer 26. The first
`transformer 22 is preferably a conventional 12-volt/3 65
`amp transformer. The top of the secondary coil 28 of
`first transformer 22 is connected through line 30 to the
`anode of rectifier diode 32, the cathode of which is
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`opening 122 in the fourth side 106 of the housing 90.
`power for starting the gas engine 162 of the boat 150.
`The cord 124 for the conventional AC plug 12 exits the
`The batteries 152, 154, and 160 are typically positioned
`housing 90 through an opening 126 in the fourth side
`as illustrated in FIG. 7, although any number of config
`106 of the housing 90.
`urations may exist due to the design of the particular
`Referring now to FIGS. 3 and 4, the light bulbs 42,
`boat 150. Battery cables 34 and 38 of the battery charger
`60, and 78, are mounted in a circuitboard 130 extending
`10 are connected to the driving battery 160. Cables 70
`parallel to the third side 104 of the housing 90. The base
`and 74 are connected to either trolling battery 154, or
`132 of each of the bulbs 42, 60 and 78, is secured in the
`152 and cables 54 and 56 connected to the remaining
`circuit board 130 with a rubber grommet 134. Each of
`trolling battery. There is also a series connection 49
`the windows 110 in the third side 104 of the housing 90
`between batteries 152 and 154. For convenience, the
`O
`passive battery charger 10 may be permanently
`has a rubber grommet 136 positioned therein for con
`tacting the lamp 138 of each of the bulbs 42, 60, and 78.
`mounted in the boat 150 using two of the mounting
`As illustrated in FIG. 5, in addition to supporting the
`brackets 164 as shown in FIG. 8, and remain continu
`base 132 of each of the light bulbs 42, 60, and 78, the
`ously connected to batteries 152, 154, and 160, at all
`circuit board 130 provides the surface through which
`times. A flange 163 of each bracket 164 is inserted into
`15
`the connections 140 between the diodes 32, 40, 52, 58,
`the lower vent slot 230 of sides 218 and 220 of the hous
`68, and 76 and the battery cables 34, 38,54, 56, 70, and
`ing 90 and is attached to the receiving surface of the
`74, respectively, and the connections 142 between the
`boat 150 with conventional fasteners by placing the
`fasteners through an opening 166 in each bracket 164.
`diodes 32, 52, and 68 and the lines 30 and 66 from the
`Referring now to FIG. 9, there is shown a battery
`transformers 22 and 26.
`20
`When charging a battery using the charger 10 of the
`charger 170 incorporating a second embodiment of the
`present invention, the current limiting light bulb 42 in
`passive battery charger of the present invention. As
`each circuit 44, for example, limits the current delivered
`illustrated in FIG.9, the battery charger 170 is equipped
`to the battery 36 to a maximum of 1.5 amps, that being
`with a conventional AC plug 172 insertable into a 120
`the maximum amps the bulb 42 is capable of pulling. As
`volt AC receptacle, with opposite prongs 174 and 176
`25
`the charge on the battery 36 increases, the voltage and
`and a ground prong 178. The opposite AC prongs 174
`amperage delivered by the transformer 22 are repelled
`and 176 are connected to the opposite ends of the pri
`by the increasing charge on the battery 36, thereby
`mary coil 180 of a transformer 182, having a secondary
`reducing the amps of the current passing through the
`coil 184. The top of the secondary coil 184 is connected
`bulb 42. Thus, as the charge on the battery 36 ap
`through line 186 to the anode of a rectifier diode 188,
`30
`proaches 100% and the amps flowing through the bulb
`the cathode of which is selectively connected through a
`battery cable 190 to the positive post of a 12-volt battery
`decrease, the illumination of the bulb 42 dims, thereby
`192. The negative post of the battery 192 is selectively
`providing a visual indication at all times of the charge
`on the battery.
`connected through a battery cable 194 to the anode of a
`The light bulb 42 prevents damage to the battery 36
`diode 196, the cathode end of which is connected to a
`35
`or transformer 22 by limiting the current flow to 1.5
`1.5 amp light bulb 198, functioning as a current limiter
`amps in the event of a reversed polarity attachment of
`for the circuit 200. The passive battery charger 170
`operates in the same way as previously described with
`the cables 34 and 38 to the battery 36, in which case the
`bulb 42 is brightly illuminated. Similarly, the light bulb
`respect to the circuits 44, 50, or 80 of the first embodi
`ment passive battery charger 10. The battery charger
`in each of the circuits 44 and 50 limits the current
`40
`through each circuit, such that a short in any one of the
`170 is, however, capable of producing a fast charge
`circuits or the connection of a dead battery to any one
`through the use of a double pole, double throw, switch
`202 which functions to bypass the current limiting bulb
`of the circuits will not interfere with the current flow
`ing through the remaining circuit. The configuration of
`198. When in the closed position, the switch 202 creates
`the circuits 44, 50, and 80 further prevents sparking 45
`a loop in the circuit bypassing the bulb 198, and closes
`when connecting the cables 34 and 38,54 and 56, and 70
`the circuit such that a small indicator light 204 con
`and 74 to the batteries 36, 48, and 72, respectively.
`nected between the switch and line 186 is illuminated to
`indicate that the battery charger 170 is operating in a
`In the event batteries 48 and 72 are connected in
`series as shown at 49 for generation of 24-volts, the
`fast charge condition. It is understood that although the
`isolation of circuits 50 and 80 from one another allows
`switch 202 is shown connected to a single circuit 200 in
`50
`batteries 48 and 72 to be charged simultaneously with
`the charger 170, the switch may be connected to multi
`out removing the series connection 49. Pairing of the
`ple circuits, such as those of the first embodiment bat
`tery charger 10. Likewise, each of the circuits of the
`cables 54 and 56 of circuit 50 and the cables 70 and 74 of
`the circuit 80 as they exit the housing 90 facilitates
`first embodiment battery charger 10 may be separately
`proper connection to the paired batteries 48 and 72. The
`equipped with switches 202 such that any one or more
`55
`passing of cables 34 and 38 through a separate opening
`of the driving motor battery or trolling motor battery
`in the housing 90 reduces the possibility of connecting
`may simultaneously receive a slow charge while the
`both sets of cables receiving power from a single trans
`remaining battery or batteries receive a fast charge from
`former 22 to the paired batteries 48 and 72, thereby
`a single charging unit 10.
`facilitating the isolation of the circuits charging the
`Referring now to FIGS. 10, 11, and 12, the trans
`paired batteries 48 and 72. By splitting circuits 50 and 44
`former 182 is mounted within a housing 210 having a
`from a single transformer 22, the passive charger 10 is
`first half 212 and a second half 214. The first half 212
`kept small and relatively light weight.
`forms a top 216, a first side 218, and a second side 220.
`Referring now to FIG.7, there is shown a top view of
`The second half forms a bottom 222, a third side 224,
`a fishing boat 150. Most fishing boats 150 are equipped
`and a fourth side 226. The first half 212 is connected to
`65
`with two 12-volt batteries 152 and 154, to provide the
`the second half 214 with conventional fasteners 228
`power through a line 156 for driving a trolling motor
`along the first side 218 and second side 220. The first
`158, as well as a 12-volt battery 160 for providing the
`side 218 and second side 220 have vents 230 therein to
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`allow circulation of air through the charger 170. A
`maximum amperage substantially equal to the maximum
`amperage of the first current limiting means.
`window 232 in the third side 224 allows the illumination
`3. The battery charging apparatus of claim 1, wherein
`of the bulb 198 to be observed there through. Mounted
`the second alternating current power supply comprises
`on the third side 224 of the housing 210 is a lever 234 for
`a transformer capable of emitting a flow of electricity
`actuating the switch 202. Also mounted on the third
`having a voltage substantially equal to the theoretical
`side 224 of the housing 210 is the small indicator light
`voltage of the battery to be charged and an amperage
`204 for indicating a fast charge condition when illumi
`substantially equal to two times the maximum amperage
`nated. The cord 236 of the conventional AC plug 172
`exits the housing 210 through an opening 238 in the
`of either the second or the third current limiting means.
`4. The battery charging apparatus of claim 1, wherein
`fourth side 226. A second opening 240 in the side 226
`each current limiting means further comprises a light
`provides an exit for the battery cables 190 and 194 from
`the housing 210.
`bulb having a predetermined maximum amperage sub
`stantially equal to the maximum desired amperage for
`Referring now to FIGS. 11 and 12, the base 250 of the
`charging the connected battery.
`bulb 198 is mounted in a circuit board 252 and secured
`5. The battery charging apparatus of claimi, wherein
`15
`therein by a rubber grommet 254. The circuit board 252
`each current limiting means further comprises a visual
`extends parallel to the third side 224. A second grom
`met 256 is placed within the window 232 for contacting
`indicator of the charge level of the connected battery.
`6. The battery charging apparatus of claim 1, wherein
`the lamp 258 of the bulb 198.
`the current emitted by the power supply decreases as
`I claim:
`20
`1. Apparatus for simultaneous passive charging and
`the battery connected thereto approaches a full charge
`thereafter maintaining of charge in a plurality of plate
`condition and repels the current emitted by the power
`supply.
`type batteries, each having a known theoretical voltage,
`a positive terminal, and a negative terminal, comprising:
`7. The battery charging apparatus of claim 1, wherein
`a first power supply having an alternating current
`the first and second batteries are connected to function
`25
`as a single power source with the first battery charged
`Output;
`a first rectifier diode having an input electrically
`by the first power source and isolated from the second
`connected to said output of the first power supply
`power source as it charges the second battery.
`and having an output electrically connected to the
`8. Apparatus for continuous simultaneous charging
`positive terminal of a first battery to be charged;
`and thereafter maintaining the charge of a plurality of
`30
`a second rectifier diode having an input electrically
`plate-type batteries, each having a known theoretical
`voltage, a positive terminal, and a negative terminal,
`connected to the negative terminal of the first bat
`comprising:
`tery and an output;
`first current limiting means having an input electri
`a first power supply having an alternating current
`cally connected to the output of the second recti
`output;
`35
`fier diode and having an output electrically con
`a first circuit loop connecting the first power supply
`nected to the first power supply;
`to a first battery to be charged wherein the first
`a second power supply having an alternating current
`circuit loop comprises:
`output;
`a first diode connected in the first loop between the
`a third rectifier diode having an input electrically
`first power supply and the positive post of the
`connected to said output of the second power sup
`first battery to be charged;
`ply and having an output electrically connected to
`a second diode connected in the first loop between
`the positive terminal of a second battery to be
`the first power supply and the negative post of
`charged;
`the first battery to be charged; and
`a fourth rectifier diode having an input electrically
`first current limiting means connected in the first
`connected to the negative terminal of the second
`loop to limit the maximum current flowing
`battery and an output;
`through the first loop to charge the first battery;
`second current limiting means having an input electri
`a second power supply having an alternating current
`cally connected to the output of the fourth rectifier
`output;
`diode and having an output electrically connected
`a second circuit loop connecting the second power
`to the second power supply;
`supply to a second battery to be charged wherein
`fifth rectifier diode having an input electrically
`the second 25 circuit loop comprises:
`connected to said output of the second power sup
`a third diode connected in the second loop between
`ply and having an output electrically connected to
`the second power supply and the positive post of
`the positive terminal of a third battery to be
`the second battery to be charged;
`55
`charged;
`a fourth diode connected in the second loop be
`sixth rectifier diode having an input electrically
`tween the second power supply and the negative
`post of the second battery to be charged; and
`connected to the negative terminal of the third
`battery and an output; and
`second current limiting means connected in the
`third current limiting means having an input electri
`second loop to limit the maximum current flow
`cally connected to the output of the sixth rectifier
`ing through the loop to charge the second bat
`diode and having an output electrically connected
`tery; and
`to the second power supply.
`a third circuit loop connecting the second power
`2. The battery charging apparatus of claim 1, wherein
`supply to a third battery to be charged wherein the
`the first alternating current power supply comprises a
`third circuit loop comprises:
`65
`transformer capable of emitting a flow of electricity
`a fifth diode connected in the third loop between
`having a maximum voltage substantially equal to the
`the second power supply and the positive post of
`theoretical voltage of the battery to be charged and a
`the third battery to be charged;
`
`10
`
`

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`5
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`5,371,454
`O
`11. The battery charging apparatus of claim 8,
`a sixth diode connected in the third loop between
`the second power supply and the negative post
`wherein each current limiting means further comprises
`a light bulb having a predetermined maximum amper
`of the third battery to be charged; and
`age substantially equal to the maximum desired amper
`third current limiting means connected in the third
`age for charging the battery.
`loop to limit the maximum current flowing
`12. The battery charging apparatus of claim 8,
`through the loop to charge the third battery.
`wherein each current limiting means further comprises
`9. The battery charging apparatus of claim 8, wherein
`a visual indicator of the charge level of the connected
`the first power supply comprises a transformer capable
`battery.
`of emitting a flow of electricity having a voltage sub
`13. The battery charging apparatus of claim 8,
`10
`stantially equal to the theoretical voltage of the battery
`wherein the current emitted by the power supply de
`to be charged and an amperage substantially equal to
`creases as the battery connected thereto approaches a
`the maximum amperage of the first current limiting
`full charge condition and repels the current emitted by
`the power supply.
`e2S
`14. The battery charging apparatus of claim 8,
`10. The battery charging apparatus of claim 8,
`wherein the first and second batteries are connected to
`wherein the second power supply comprises a trans
`function as a single power source with the first battery
`former capable of emitting a flow of electricity having
`connected through the first loop to the first power
`a voltage substantially equal to the theoretical voltage
`source with the first loop being isolated from the second
`of the battery to be