US2642520A - Portable rechargable flashlight - Google Patents

Description

June 16, 1953 R. s. COOLIDGE ETAL PORTABLE RECHARGEABLE FLASHLIGHT 3 Sheets-Sheet 1 Filed Dec. 21, 1946 INVENTORS' ATTORNEYS June 16,1953 CQQLIDGE r 2,642,520

I PORTABLE RECHARGEABLE FLASHLIGHT Filed Dec. 21, 1946 3 Sheets-Sheet 2 INVENTORJ ATTORNEYS J1me "1953 R. s. COOLIDGE ETAL 2,642,520

PORTABLE RECHARGEABLE FLASHLIGHT 3 Sheets-Sheet 3 Filed Dec. 21, 1946 QM MM NM lNVEINTQRs- BY 1 awn/7, AA/v.07, M

ATTORNEYS Patented June 16, 1953 PORTABLE RECHARGABLE FLASHLIGHT Roger S. Coolidge, Center Sandwich, N. 11., Harry W. Keely, New York, N. Y., Reginald S. Smith, Nor-walk, Conn., and Tore N. Anderson, Huntington Station, N. Y.

Application December 21, 1946, Serial No. 717,776

8 Claims. 1

This invention relates to a self-contained portable electric light. More particularly the in.- vention relates to an improved portable flashlight which is capable of being recharged.

One of the main features of this invention is to provide a novel portable self-contained flashlight which is capable of being recharged from the ordinary house lighting circuit or other ordinarily available circuit.

Another particular feature of this invention is the provision of an improved hand flashlight of the ordinary design which may be recharged from an electrical circuit and which has all of the necessary instrumentalities carried within the flashlight so that it may be recharged from any ordinary circuit and not be required to be returned to a, particular house or other lighting circuit or instrument attached thereto.

Another feature of this invention is to provide a rechargeable portable self-contained flashlight wherein there is a quickly withdrawable electric attachment plug that may be conveniently connected to a wall or floor socket, and the flashlight storage portion thereof allowed to be recharged with convenience and ease.

A further feature of this invention is to provide what is known as a hand flashlight of the common size and of transportable nature, and to provide within the casing thereof a rechargeable battery and a light weight, simple, electrical instrumentality that is readily connected to any house or ordinary lighting circuit (A. C. or D. C.) and which acts to provide direct current of low voltage for charging the battery.

Another feature of this invention is the provision of an improved rechargeable, light weight, hand flashlight that is of simple construction, and of low cost, and may be readily carried. This flashlight may be made in the pocket sizes or the larger hand carrying sizes.

A still further feature of this invention is the provision of a filler unit of a rechargeable battery, an electrical instrument for transforming electrical power from an ordinarycircult to low voltage direct current for charging the "battery, and of desirable electrical connections. This unit is available for insertion into the casings of the ordinary hand flashlights which heretofore have received only the replaceable dry batteries.

A particular advantage of this invention is that the total weight of the improved flash-' light is considerably less than the present hand" flashlights that use dry cells. It. is now possible by the invention herein, to provide a lighter weight battery and have one that does not swell up and clog the flashlight case thereby eliminate ing the difliculty of removing swollen dry cells. It is known that dry batteries will swell if not used. Another particular advantage is that the im. proved battery now employed herein has a substantial indefinite shelf life and uses an alkali electrolyte instead of an acid electrolyte. This is very helpful in the event the whole flashlight is crushed or damaged for any reason, for the alkali electrolyte will not damage the articles or material it touches, as severely as an acid electrolyte.

Another advantageous feature of the flashl ht device h rein described is that there is provided a non-leaking liquid, rechargeable battery.

As part of this device, there is provided an improved means for providing for the automatic cut-01f of the charging current when the battery has been well charged.

In the preferred construction herein, there is the possibility and the advantage of using that part of the flashlight empl yed for charging he battery, for other purposes. For instance, it is possible in the improved structure herein to disconnect the busbars or electrical connections leading from the charging instrument to the battery and connecting it to other apparatus for charging their operating batteries, such for instance, a hearing aid device, or electric movie camera, or the like.

When it is desired to employ the charging portion of this flashlight for charging other devices, and at the same time it i desired to use the flashlight, the battery and the electrical charging element or means may be disconnected and the battery return to its normal position in the casing and a suitable type of filter mounted behind the battery in the casing to maintain the battery in flashlight operating position.

This invention provides for a novel type of rechargeable portable flashlight that is capable of being charged from the house lighting circuit. The designation of such a circuit is for purpose of illustration for it will be understood that any ordinary circuit that is available as long as it is not of too high voltage.

The house lighting circuit of A. C. or D. C. is very satisfactory as it is available most any place. The flashlight may be easily provided with the type of electrical transforming means that will receive without damage electrical power of 220- volts where most of the house light circuits are of 110-volts. Any of these available circuits, industrial or house, will hereafter be understood as coming within the statement of commercial or house electric circuits.

In addition when referring to portable flashlights, the term is understood to include the ordinary hand flashlight of small, pocket size, hand lantern type or the like, and the shape of the casing may be as desired, tubular, rectangular, or otherwise.

Further advantages and improvements will be noted in the following description as supplemented by the disclosure in the drawings, wherein:

Fig. 1 is a sectional View of a flashlight case showing a lamp and reflector and some of the electrical connections;

Fig. 2 illustrates the flashlight apparatus partially withdrawn from the casing and in battery charging position;

Fig. 3 is a top plan view of the battery and the I charging element and electrical connections therefor, all forming a unit which is slidable in the casing taken nections of the flashlight with the charging instrument;

Fig, '7 is a sectional view of a valve for each section of the battery which permits gas under pressure to leave the top of the battery but which prevents the leaking of the electrolyte;

Fig. 8 is a side view of a flashlight operating unit which may be inserted in a casing now owned or possessed by a user;

Fig. 9 shows the unit illustrated in Fig. 8 in place in the ordinary casing owned by a user;

Fig. 10 is a modified wiring diagram of the unit and shows the battery in dotted lines;

Fig. 11 is a side View partly in section, showing means for opening the electrical circuit when the battery has been sufficiently charged, thereby forming a cutofi; and.

Fig. 12 is a View of an adaptor usable to attach electrically for charging the battery of a device other than the flashlight.

Referring nowtc these drawings, there is provided a suitable type of outside casing 15, preferably tubular, of what is now commonly known as a hand flashlight. A suitable type of head 16 is shown for closing one end of the casing l 5. This head carries an electric lamp I! which is suitably positioned in a reflector l8. This head also carries a lens Hi. In addition, it is preferred to have the lamp mounted so that it is movable in respect to the reflector to thereby vary or change the focus of the light beam at will. Such movements may be accomplished by moving either the lamp or the reflector.

The other end of the tube is provided with a suitable cap 20 which may be of any desired shape and material so long as it readily withstands usage. It is preferred to have this cap 20 made of transparent material, such as plastic or other like material, so that the terminal ends of the power recharging unit as assembled in the tube may be seen thru the cap. In some instances it may be desired to have this cap 20 fastened to the tube l5 by any suitable means, such as a wire or cord 2 l, or any flexible means so that t e p 4 will not be lost while it is removed during battery charging operation.

Part of the electrical connections in the casing are readily noted in Fig. 1 wherein the base contact 25 of the lamp I! will engage contact 25 when head I6 is assembled in position on casing l5.

An electrical connection 26 herein preferred in the form of a channel shaped bus bar, is provided with a spring end 21 for engaging the reflector !8. This type of engagement allows the head I6 to be screwed into position on the casing 15 and provides for continuous contact of end 21 with reflector IS. A second bus bar 28, preferably of the same structure and design, connects contact 25 with a spring portion 29 of a hand switch 30. This spring portion 29 is connected to a second part 3! of a bus bar leading toward the rear of the casing. The switch 33 is provided with a button 32 for pressing to close the switch 33, and with a sliding button 33 which may be moved forward to close the spring 29 on to the bus bar portion 28 for holding the switch closed without keeping the users fingers pressing on button 32. This type of switch 30 is the usual type employed in flashlight devices.

It is preferred that the bus bars 26 and 3| extend to points near the end of the tube l5; These connections or bus bars may be of any particular design but are preferred to be provided in the forms shown in Fig. 5 of channel construction so that contacts carried on the battery will easily and firmly engage therewith and be slidable there in. At suitable points in the bus bars, there are provided sections of insulation 35 so that during charging of the battery, no current would reach the switch 30 nor the lamp I1.

In providing suitable means, in this instance, a battery, for supplying electrical'power to the lamp I! and for providing an instrumentality for recharging the battery, reference is particularly made to Figs. 3 and 4, wherein there is shown a battery 36 and a battery charging means 3! and terminals or prongs 38 which are adapted to be plugged into a house lighting circuit. It is preferred that the battery 36 and the charging instrument 3'! and the terminals 38 be mechanically connected together as well as electrically connected for the purpose of providing a unit ,which is readily removable from the casing I5,

for repair or replacement of any of the parts. Instead of providing prongs38 for the electrical connections, it will be understood that there may be sockets to receive plug prong electrically connected to a commercial circuit.

In providing the type of unit here noted, the battery 36 is provided with electrical conducting arms 39 which carry contacts 40 that engage and are slidable and are guided in the bus bars 26 and 3!. Conductors 4! and 42 lead from a base 43 through pivot points 44 and 46 for conducting the charging current to battery 36. Preferably, this base carries the prongs 38 for plugging into th house electric light circuit. The pivot points at 44 and 46 are preferably of the snap type so that they may be readily connected or disconnected.

In using electrical power from an ordinary circuit and for changing that power to low voltage direct current for charging the battery, a suitable electrical instrumentality is provided. In the form herein preferred, there is an electronic means or tube which is adapted to be carried in the flashlight casing so that the flashlight battery may be recharged from any house lighting or available circuit.

For this purpose a preferred type of tube, the connections of which are shown in Fig. 6, is provided. Such a tube may be any one of the following tubes: 117Z6, 50Y6, or 45Z3. It will be noted that a feature in using such tubes is that the filament does double duty in its new use herein. :Such doubl duty is that it first acts as a resistor to heat the cathode and then it acts as a voltage dropping resistor. When it is desired to start the tube into operation, the filament of the tube is heated. For that purpose a small switch 41 is provided to connect that portion of the tube across the house lighting circuit for a short interval of time.

It has been found that a suitable electronic tube 31 of any of the types referred to having particular operating characteristics is satisfactory for the purpose. This tube receives the 110- voltage or other voltage power from the .house lighting or other circuit and if the lighting circuit is alternating current, it will transform that current into direct current, and it will reduce the voltage to a desired figure. If the house lighting circuit is direct current and the plug is inserted in the circuit in the wrong direction, the filament of the tube will glow while connected across the lighting circuit but will not glow when the switch 41 is opened. The terminals of the plug should then be reversed and the instrument will operat normally to charge the battery. The electronic tube, Or tubes, may be installed to produce 50 to 200 milli-arnperes charging current per tube for this or other purposes.

In providing the improved electronic instrument for receiving the electrical power and for modifying it to give the low voltage direct current for charging the battery, it i understood that instruments other than the types referred to may be designed to obtain the desired results. In the instrument employed here, it is preferred that there be a filament which is first used as a resistor to heat the cathode to place the instrument in electrical operation, then the filament is used as a voltage dropping resistor, and as a regular cooperating filament element of an electronic tube.

It will be seen that battery 35, tube 31 and base 43 may be readily removed as a unit from the flashlight casing so as to change tubes when desired or to make any repairs.

In the normal charging of the battery, it is desired to remove cap and to pull the unit out until the battery 36 shows, as indicated in Fig. 2, and the end of the casing I5 is allowed to drop down and touch the floor, or if the house socket is above table height, the head [6 of the flashlight may rest on a table to preferably give a position illustrated in Fig. 2. In order that the battery shall not be pulled out too far, a suitable stop 49 or any other adaptable means, may be provided for arresting the withdrawal of the unit. This stop is preferably such that it may be withdrawn so that the whole unit may be easily taken out of the casing for repairs or for other purposes. It is also desired that the bars 4| and 42 be insulated. A suitable insulation is shown in part at 5| in Figs. 2 and 3. It is desired that no portion of the electrical circuit, such as the main switch, shall be free to cause any electrical shocks to the user.

It is to be understood that the charging of the battery may be accomplished by leaving the unit assembled in the casing. It is preferred, however, that the charging shall be accomplished with part of the unit withdrawn as shown in the position illustratedin Fig. 2 so that if the electronic means 31 gives off appreciable heat, it may be radiated without being required to be absorbed by the casing l5, or by providing the interior of the casing IS with suitable asbestos or other heat resistant lining to thereby prevent any damage to the casing.

In carrying out the charging of a wet battery, preferably of the oval type, as shown, in the preferred manner, it will be noted that the battery 36 will be in a tipped position. This is advantageous so that the spaces above the electrolyte will communicate with plugs 52 and 53 to allow any gas which may develop and be under pressure to escape from the battery but will prevent the electrolyte from leaking from the battery. Any suitable type of apparatus may be employed for this purpose, but it has been found that these plugs 52 and 53 have shown satisfactory results.

, A section of one of these plugs is shown in Fig. '7,

wherein a passageway 54 connects to the space above the electrolyte. The upper end of the passageway 54 connects with a channel 56. A rubber collar 51 is provided in this channel and is tight fitting in the channel 56 so that liquid cannot come out of the battery except under excessive pressures but gas under pressure may move between the surfaces of the rubber and the channel 56. Thus, there is provided in a portable flashlight, a non-leaking, rechargeable wet battery.

In the portable flashlight device herein, it is desired to provide suitable means for modifying or rectifying the electric power from the house or other circuit and for reducing the voltage thereof so that a low voltage direct current will be impressed upon battery 36.

Heretofore, it has been known to provide a small motor generator set but these devices are heavy and complicated and are not suitable in any manner for hand, portable flashlights, or for the relatively small flashlights which a person may readily carry.

In the present invention, it has been found desirable to provide an electronic tube in which the parts thereof are provided to cooperate to supply the desired voltage and current for charging operations. In the preferred type of electronic tube, which has proved satisfactory in this type of apparatus, there is provided one or more filaments 58 and 59. In some tube types, one such filament is often satisfactory. In starting the tube, the starting switch 41 is closed, thereby passing the house lighting circuit through the filaments 58 and 59 to heat them and thus bring the tube 31 into operating condition to impress on lines or bus bars M and 42 the direct current at the desired voltage. When these filaments have been heated sufficiently, the tube 31 starts its normal functioning and the switch 41 is opened upon releasing it.

For the purpose of further detailed explanation of this improved battery charger, and in stating the theory of operation insofar as it is now understood, the following detailed description is made when employing, as an example, the use of a 50Y6 tube operating on 117 volt, 60 cycle A .-C. source of electrical supply.

It will be noted that filaments of the tube are placed across the lines by pressing switch 41, and this immediately starts to heat the cathode so that thermionic emission may take place.

At the instant of closing the switch, an inrush current of the order of 500 milliamperes flows through the filament (or heater element, socalled) which is connected between points 2 and I in Fig. 6. This inrush current is due to the low cold resistance of the heater (approximately 200 ohms). This may cause a bright glow in the support wires due also to this high inrush current. The heater resistance, in a matter of one to three seconds, increases to approximately 500 ohms resistance, and thus limits the current flow at 110 volts to 200 milliamperes, which is not dangerously close to the burn-out current value for the support wires. Furthermore, since the heater wires will tolerate much higher currents than the support wires, there is even less danger of burning out said heater wires.

After the cathode and associated heater structure comes up to a bright red heat, an indication is thus given that it is no longer necessary to hold switch 4'! closed, and the switch may accordingly be released.

When the switch is open under the above conditions, the continued red glowing of the cathode is an indication that the battery is charging. If the charger is operated from a 120 volt D.C. supply main and the plug is incorrectly polarized (that is to say, plugged in so that the plate of the tube is not connected to the positive side of the line) then the heater element will not continue to glow, thus giving an indication that the unit is not connected properly, and that the plug must be reversed.

As mentioned above, the switch 4? is left closed only long enough to thoroughly heat the cathode and furnish enough electron emission to allow the current to flow from the plate to the cathode during the portion of the applied alternating current cycle when the plate of the tube is positive with respect to the cathode. The point at which a red glow is observed is the same as that at which satisfactory electron emission is occurring.

Since current will flow through the tube (and, of course, the battery which is in series with the plate) only when the plate is positive with respect to the battery, a pulsating direct-current (of the order of a 100 milliamperes for a series of batteries) is caused to flow through them, thus charging them. Thus, charging can be accomplished with this circuit until the series of batteries reaches a back voltage of approximately 12 to 15 volts, at which time the tube and heater will not be sufficient to maintain the cathode emission at a high enough value to keep current flowing through the tube and batteries.

After the switch 47 is opened, the voltage drop through the tube (tube resistance is sometimes called D.-C. plate resistance) is automatically placed in series with the heater resistance and the battery resistance to limit the current flow. Current, when operated from 117 volt 60 cycle supply, flows only during the half-cycle when the plate is positive with respect to the cathode. The heater element is maintained at a temperature suitable for electron emission by the thermal lag in the cathode and heater structure.

The battery load in electron tube charging circuit is a very small part of the total circuit resistance, and the back E. M. F. up to 12 to 15 volts approximately represents only about 10% of the total voltage drop through the circuit, and thus, in effect, is negligibly small. Conversely, if the battery size is reduced, providing it can tolerate 100 milliamperes, the circuit still remains operative. If by chance the battery is short circuited, the tube will not be injured, but will continue to remain operative.

In the preferred tube 3! there is provided a base 60 which has the various prongs numbered By employin this type of electronic instrumen 1 tality or tube, it has been found possible to provide an efficient, low cost, light weight, rugged,

portable flashlight that is rechargeable from any house lighting circuit.

In the present preferred form of incorporation of elements to provide this improved flashlight, it is desired to have the battery and charging means and elements to connect to the house lighting circuit removed as one unit. Itwill be understood, however, that these may be changed and improved to meet different types of uses and conditions. For instance, the battery may be mounted in the casing so that it is not movable except for replacement purposes and flexible wire connections employed to connect it to the tube and to the base.

Referring now to Figs. 8, 9 and 10, there is illustrated a combination of elements preferably comprising a battery and special electronic tube and modified electrical connections. Thiscombination comprises a filler unit which any person may purchase separately and insert in the flashlight tubing or casing or holder'which he now owns and which was originally purchased to hold dry batteries.

In this type of unit, the battery 36 is provided with an end contact 6! which will engage the base 24 of a lamp. The tube 31, with its base 50, is a tube of special characteristics andis mounted on the head 43 which, in this instance, is provided with prongs 38, but which head may be formed as a socket so as to receive suitable prongs of a connector from a commercial electric circuit. 7

Suitable electrical connections between the tube and the battery may be employed and are here shown as the bars 4! and 42. In this instance, these are directly connected to the battery.

Referring now to Fig. 9, it will be seen that the battery 36 is mounted in the well known casing 62 and provides for the contact iii to engage the base of the lamp. Closing cap 20 in this instance, includes a spring 33 which will force the head 43 to the left for the purpose of keeping contact Bl in engagement with the base 24 of the lamp. In

the event it is desired to provide a cap 2!] with-' with each other, as noted in the wiring diagram in Fig. 10, although in many instances only one of them is needed. The casing 62 is provided with a suitable insulating sleeve 66 which is of shorter length than casing 62 and which the contacts 64 will engage when the unit is moved to the right to take the position shown in Fig. 2 for charging the battery. Thus, there will be no danger of shocks tothe owner of the flashlight while the battery is being charged.

Referring now'to Fig. 10, there is a modified form of wiring diagram different in few respects to that ofFig. 6.

The outline of battery 36 is 7 shown in dotted form and is represented at $1 for clearness of the wiring diagram.- The tube 1 3.1 one f the t pes r ierr d o so a to have definite chara teristics o fi he ne e e there is a defi ite v l a e and a fi te o e t equiremen he filament t a d. .9 o th be he p vid d t btain th d s red c ar in vo ag a d current. These filamen s act i h beginning a heat rs as note above when the star n tc .1 is closed. and a erw ds upon th o e in oi switch 41 they not as ro p n r istors an as the filaments n th tub 3 Therei e. the ube 31 is constructed to ha e one r more filamen u ts, depending upon he iunot onel re ui e-- ments of the tube and the voltage desired for its particular install tion- In the event t is se ra operating or filler nit of a lashli ht is nserted n e a in w ic is mad o a non cond ot r or u ale mate: rial such as p astic, or the like, it will be desi ab e to use he ele tr a n ect s l trated in Fi 9 a av the top o duc o s 54 en a e the lone tudineu nnector unn to he rear of the se fr m the ht ha d d o i h 30 within he cosine. th by c m letin t ircu at intervals s he s i c 3 is perated f desire he l r ca onn c ion of the unit to he lamp a d thr u h t swi ch 3 and ack t t e ne ative s d o e atte y ay b complished in a ot er su table mannern assemblin theu t n h casi sh w i i .9. any suit le c nst uc n a e e plo ed to maintain the un t oin movin c cula ly espect to th as n Qne ma ne of e om p h ng t s res l s to ov de abl x eni s f nsul tio pie 6.6 so that t e ex ensi ns st add e ach ide of ontacts 54, thus holding them in position to preyent rel tive rota ion The insulation piece .576 is preferably d finitely held in position in the threads at the right hand end of the casing. Another means of accomplishing this same result wouldbe to have spring members extendin f o the bo y of battery 36 so they would engage any groove, or grooves, in the casing 52 itself. When the unit is inserted in a plastic case, such spring members would be adap d to eng ge any longitudinal hump ordepression in the casing, thereby preventing a relae tive rotary movement between the case and the unit. In some designs of plastic cases, an clone trical conductor is riveted longitudinally to the inside thereof, and it is desired that the spring members willhave insulation on their ends and will engage each side of the electrical conductor to prevent any relative .rotary motion between the casing and the unit. Thus, the conductors and switch means for the units when assembled in plastic cases will be retained in proper operating position.

It will be noted that this type of filler unit to be inserted in the present casings, originally designed for holding dry batteries, is simple, easily handled, and readily assembled into the casings which the user or owner already has.

Referring now to Fig. 11, there is illustrated one form of means for automatically disconnecting the charging current to the battery. In some types of batteries, it is desirable to have the charging current impressed on it for only a def.- inite time. Most alkali wet batteries; being charged to their capacity for receiving electricity, cause the electrolyte to gasify to some extent. It is desirable to open the charging current circuit then .or shortly after gassing starts and has built .up a definite pressure in the battery. In the type of battery which does not start gassing until 10 charging has been substantially completed, the pressure will then buildup and charging will continue until'pressure within the battery operates to automatically open the charging circuit.

In the disclosure herein, there is shown a preferred form of employing this pressure to open the c rc t o the e tterv an for automatically opening the electrical power to the tube. The preferred means for this purpose includes a bellows or pressure membrane "Ill, Fig. 11, which may be of any desired flexible or plastic material which pr fe a p lses o push he sprin lever l hat arries an e eot ieel eonouoto h preferably is molded in the side of the battery casing and whi h connects to the up n of the b y at contact 13. The end of wire 12 engages conteot l wh ch no l is in e g m t with contact 76 which is carried by a suitable bracket 17 th ele t ically nnects h co act 6! t a n a es th base. o amp lh w t s ie r d construction th circu t l a t m al be open d by rea on o pre sur de op d i th battery when the battery has become substantially tully charged. In opening the circuit, the circ i throu h th fi amen or fi m n in the tube will also be opened and these filaments will cool off-and the pressure in the battery will ree duo or e released, whatever typ of battery is employed, and the contacts '14 and 16 will return o en a i g position, but the tube 31 will not operate when these contacts again close because the filaments have been cooled off and can only be started again in this type of device by clos ing the starting Switch 4'! to heat them to a point of operation.

In some types of batteries, they may be provided with a suitable type of porous vent so that the pressure will slowly decrease therein, thereby allowing contact 74 to become reengaged with contact 16 to close that part of the circuit and be ready for operation when the tube filament has again been heated.

Therefore, the battery will be automatically disconnected on charging when it has been substantially charged to its capacity. This is a great advantage as the life of the battery and the flashlight will be prolonged to a very large extent.

With this type of battery which automatically disconnects the charging circuit when the battery has been recharged .to substantially its capacity and the tube 31 no longer glows and the flashlight remains in position shown in Fig. 2, the observer can readily see that the charging has been completed and the flashlight ready for reassembling and'operation. Thus, the user does have an indicator readily observable in that the tube will be glowing during charging and will be black or non-glowing after charging has been completed.

In the broad aspects of this invention, it will be noted that there have been provided a flashlight lamp and a rechargeablenon-leaking battery connected in .circuit with a switch for flashin the lamp o and .o i- In addit o e e is providedan electrical means or ec in e cical power from the ordi a or h u lighting circuit and ;,for l'ei tifying or modifying it and limiting the current flow thereof to a satisface Y amount fo im ess di u t On to the battery ior recharging purposes.- This combination of elements or constituent parts may be held together in any desired fashion to provide Proper functioning and cooperation in operation, and for easy repair or replacement. In the preferred i rhi the e el me ts a m d in a casing which is easily handled and which provides proper switching means for having each element perform its desired function.

This improved flashlight, as disclosed herein, may be charged from either a direct current or an alternating current lighting circuit. When the circuit is direct current, the battery is easily charged by reversing the prongs 38 if the tube ceases to glow when the switch 41 is opened.

It is also to be pointed out that there is a great advantage in a portable hand type flashlight to have a rechargeable battery that employs an alkaline electrolyte instead of an acid electrolyte. This is advantageous in the event the body of the battery becomes defective. Such an alkaline electrolyte will not damage and eat away parts of the casing, or materials which it may touch, to the extent that any acid electrolyte will.

The improved portable, rechargeable, hand flashlight may be made in various sizes from pocket size up, and may be charged from any handy, commercial electrical circuit whether alternating current or direct current and does not require being returned to a particular type of power rectifying circuit or apparatus in order to be recharged. By use of the improved type of non-leaking wet battery, the life of the flashlight has been materially improved and the storage or shelf life does not create changes in the various elements constituting the flashlight.

Many changes and modifications may be made in the several preferred forms illustrated and described herein but such changes and modifications are considered as coming within the scope of this invention, as outlined in the following claims.

The invention claimed is:

l. A portable rechargeable lighting device, comprising a casing, an electric lamp therein, a rechargeable battery, a switch electrically connected in a circuit with said lamp and said battery, an electronic tube removably mounted in said casing for supplying charging current to said battery and for receiving current from a house lighting circuit, said tube having a filament therein, and a switch in circuit with said filament and the house lighting circuit for heating said filament to condition said tube for operation and thereafter to be opened, a part of said tube thereafter operating as a voltage dropping resistor.

2. A portable flashlight, comprising a casing, a lamp mounted within said casing, a rechargeable battery carried by said casing and adapted to be slidable therein, an electric circuit maintainable between said battery and said lamp, a switch in said circuit for supplying power from said battery to said lamp, a base carried by said casing, electrical prongs extending from said base for connecting into a house lighting circuit, an electronic tube carried by said base for receiving power from the house lighting circuit and for providing low voltage direct current for charging said battery, electrical connecting means between said tube and said battery, and a filament in said tube responsive to initial current for heating itself and thereafter to act separately as a voltage dropping resistor to provide low voltage current for charging.

3. A portable flashlight, comprising a casing, a lamp mounted within said casing, a rechargeable battery carried by said casing and adapted to be slidable therein, bus bars carried by said casing, contacts on said battery having slidable 1'2 contact with said bus bars thereby maintaining an electrical circuit between said lamp and said battery, said bus bars also acting to guide the sliding of said battery, a switch in said circuit for supplying power from said battery to said lamp, a base carried by said casing, electrical prongs extending from said base for connecting to a source of electrical power, an electronic tube carried by said base for receiving the electrical power and for providing-low voltage direct current for charging said battery, and electrical connecting means between said tube and said battery.

4. In a portable flashlight, the combination of a tubular casing provided with electrical bus bars extending most of the length thereof, a switch for opening and closing one of said bus bars, a head provided for engagement with one end of said casing, a lamp carried in said head and electrically connected to said bus bars, a non-leaking rechargeable battery slidable into said casing, contacts carried on the side of said battery for engaging said bus bars, a base provided with prongs for insertion into a house lighting circuit socket, an electronic tube mounted on said base for receiving power from said house circuit and for transforming said power to low voltage direct current for recharging said battery, a switch for temporarily connecting the filament of said tube across the house lighting circuit until said filament is heated, part of said tube thereafter operating as a voltage dropping resistor, and means joining said base and said battery for maintaining the same in assembly in said tube or in chargeable position, said base and said tube being withdrawn from said casing during charging.

5. In a portable flashlight, the combination of a casing, a lamp in said casing, an electrical rechargeable means carried by said casing and connected to said lamp for supplying electrical power thereto, a lamp switch electrically connected to said lamp and said rechargeable means for controlling the power supply to said lamp, an electrical device in said casing and connected to said rechargeable means for controlling the charging thereof, contacts carried by said electrical device to be connected at will to an electrical charging circuit, a switch associated with said electrical device for connecting an element in said device in shunt with the electrical charging circuit to have said element separately and first act as a resistor for heating itself, said switch opened after the heating to have said element connected in series with one side of said charging circuit to separately and secondarily act as a voltage drop resistor to provide proper charging voltage through said device to said rechargeable means.

6. In a portable flashlight, the combination of a casing, a lamp in said casing, an electrical rechargeable means carried by said casing and connected to said lamp for supplying electrical power thereto, a lamp switch electrically connected to said lamp and said rechargeable means for controlling the power supply to said lamp, an electrical device .in said casing and connected to said rechargeable means for controlling the charging thereof, contacts carried by said electrical device to be connected at will to an alternating current house lighting circuit, a resistor element forming part of said electrical device, a switch associated with said electrical device for connecting said resistor element in said device in shunt with the electrical charging circuit to have said element separately and first act as a resistor for .heating itself, saidswitch opened after the heating to cause said resistor element to be connected in series with one side of said charging circuit for acting separately and secondarily as a voltage drop resistor in order to transform the alternating current to direct current and to reduce the voltage for charging said battery.

7. A portable flashlight comprising in combination a tubular casing, an electric lamp mounted in one end of said casing, a rechargeable battery carried in said casing and electrically connected to said lamp for supplying current thereto, a lamp switch for controlling the electrical supply to said lamp, a first electrical circuit having therein said lamp and said battery and said switch, an electronic tube carried within said casing, a second electrical circuit having connected therein said electronic tube and its connections to said battery, a pair of electrical terminals carried by said tube and adapted to be connected to a house lighting circuit for recharging said battery, a cap for fitting over the other end of said tubular casing to enclose said terminals when said tube is not connected to a charging house lighting circuit, said tube having a filament to be connected to said lighting circuit, and a switch connected in said second circuit for temporarily connecting said filament in shunt with said house lighting circuit to heat said filament and then to open to allow said filament to automatically be connected in series with said house lighting circuit and to have said filament reduce the charging voltage and to convert the house lighting circuit to direct current.

8. A portable flashlight comprising a tubular casing, an electric lamp mounted in one end thereof, electrical bus bars carried on the inside of said casing and having said lamp in circuit therewith, a two compartment rechargeable battery carried in said tubular casing and having contacts engaging said bus bars, one compartment of said rechargeable battery holding the battery electrolyte, a battery switch mounted in the other compartment and normally being closed and subject to excess gas pressure in said electrolyte to be pressed open, a lamp switch for controlling the electrical supply from said battery to said lamp, an electrical circuit having therein said lamp, said rechargeable battery, said battery switch and said lamp switch and said bus bars of length to permit said battery to have predetermined relative movement to said casing, an electronic tube movably mounted in said casing and being electrically connected to said rechargeable battery for charging the same from a house lighting circuit, said rechargeable battery and said tube being mechanically connected together to permit partial withdrawal from said casing when desired to connect said electronic tube to a house lighting circuit, terminals carried by said electronic tube to be connected to said house lighting circuit, a filament in said tube for temporarily acting as a resistor for heating itself and thereafter acting as a voltage drop resistor for correctly charging said battery, a tube switch for closing said filament in shunt with the house lighting circuit and when open after heating said filament to place said filament in series with said lighting circuit to have said filament act as a voltage drop resistor.

ROGER S. COOLIDGE. HARRY W. KEELY. REGINALD S. SMITH. TORE N. ANDERSON.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,034,108 Halbleib July 30, 1912 1,230,004 Meikle June 12, 1917 1,267,199 Ferguson May 21, 1918 1,506,302 Hopkins Aug. 26, 1924 1,506,303 Hopkins Aug. 26, 1924 1,528,709 Trimble Mar. 3, 1925 1,596,131 Vorberg Aug. 17, 1926 1,717,563 Hull June 18, 1929 1,861,789 Davis June 7, 1932 2,176,479 Willis Oct. 17, 1939 2,293,284 Emanuel Aug. 18, 1942 2,425,743 Knight et al. Aug. 19, 1947

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