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Publication numberUS2550234 A
Publication typeGrant
Publication dateApr 24, 1951
Filing dateDec 9, 1948
Priority dateDec 9, 1948
Publication numberUS 2550234 A, US 2550234A, US-A-2550234, US2550234 A, US2550234A
InventorsDuncan James J
Original AssigneeDuncan James J
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Combination flashlight and circuit tester
US 2550234 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)


ATTCI R N EYS Patent'edApr. 24, 1951 I a a "James Lp ncan, Flint, Mich; l ppli'c'ation December 9, 1948, Serial No. 64,398

. circuittester which Whil'e adapted. for various purposes and uses, is especially designed; in add'ition to the performance or its: functions as'a flashlight, is also equipped for testing the circuits 01E various electric equipments.

The combination structure includes a minimum numberof parts that may with facility be manufacturedat low cost of production, and the parts may be assembled with convenience to insure a compactly arranged appliance or this nature that is simplein construction and operationydurable, and reliable't in the performance of'its various functions. 1 I

The invention consists inscertain novel featuresof constructionand combinations. and arrangements of parts as .willihereinafter' be described detail and mor e. particularly pointed out in theappended claim.

In the accompanying drawings I have illustrated two physical embodiments of my invention in which the parts are combined and arranged in accord with modes I have devised for the practical application of the principles of my invention.

It will however be understood that changes and alterations are contemplated and may be made in these exemplifying drawings and electrical and '1 mechanical structures, within the scopeof 1 my claim without departing from the principles of the invention. 7

Figure 1 is a view of a standard type of flashlight, partly in section, and equipped with the electrical testing apparatus. Figure 2 is a top s-plan View of a portion of the appliance in Fig.

1 showing the dual switch housing and switches;

' and Figure 3 is a view at the right end of Fig. 1.

the-lamp bulb 4 that is confined in the front reflector cap 5, and the usual, spring pressed rear cap 6 holds the cells in contact, while a spring supporting clip or hanger for the flash- A light is indicated at 1 as mounted upon the exterior of the tubular or cylindrical casing.

011 the-exterior of. the casing or barrel I a-metallic housing '8' is mounted, and provided with two separated compartments insulated at and B, inwhich a lamp switch and a test switch are manipulated to control the lamp circuit alone, 7

or jointly: boththe lamp circuit and the testing circuit.

0 For the lamp circuit a sl'idable and resiliently d'epressible switch is secured" to "the. fiberin sulating 5i acket B located 'within" the casing, and

an exterior springjsupported push button orcap S is provided with a screw l0 that fastenssithe cap to a movable contact head lzl within the housing, and theqmovable contact co'acts with a stationary contact of the switch which "is' formed by the rear angular-free head l'2 of a forked conductor strip l3; Thestrip is located within the insulating jacketiBy-aridfithe station,-

a'ry contactprojectsthrough ax-slot in the jacket,

while "the-front end of the strip 13: isigrounded on the reflector I4 for the bulb or lamp 4. l

The l amp circ'uit is completed through. the usual grounded connections from the lamp assembly to the battery, cap 6 and thence through a rivet l5 that fastens the insulator jacket B and a conductor plate I6 within the casing I,

the plate [6 with the housing 8.

The testing switch is secured to the metallic part of the casing, and to provide the stationary contact for thisjswitch the conductor strip I3 .is fashioned with another and spaced angular head l8 that projects through a slot in the jacket B into the insulated testing compartment of the housing 8.

The testing switch is similar in construction and operation to the lamp switch, and the movable contact head l8 ,slidably mounted in the housing, is provided with a screw l9 upon which a spring supported and depressible cap or button 20 is mounted exterior of the housing. For testing purposes an insulated wire or cord 2|, having a bare end 22, adapted for use as a connector, is detachably attached by terminal 23 to the testing switch compartment of the housing; and a second insulated wire 24 having a bare end 25 is detachably connected by screw 26 to the casing cap 6, for completing the testing circuit in series with the lamp circuit.

In the modified form of the invention shown in Figs. 4 and 5, where a pencil type of flashlight is disclosed with a battery 21 and a lamp bulb assembly 4, a conductor blade 28, having a flange 3 29 grounded on the lamp assembly, is fastened against the inner side of the insulating jacket B and provided with a headed rivet 39 which extends through the wall of the casing and into the interior of the housing 8 to form a fixed contact for coaction with the movable contact I6 of the testing switch 20, which is resiliently supported and slidable to on and ofi position within the housing 8; Q I

A second'conductor strip 3| grounded by rivet 32 on the insulated housing of the test circuit, is also provided with a rivet 33 having its exterior switch, and the movable contact member of the 1 lamp switch includes a spring blade 3 mounted exterior of the casing and adapted to slide-into contact with the head 33. ,7 p p v The spring blade 34 is provided with a grooved slide head 35 adapted to be guided in the side walls of a slot 36 in the casing, and it also performs the functions of a clip or holder for securing the flashlight pencilin a pocket; A the flash- -light pencil is slipped into'the pocket the clip 34 engages over the edge of the wall of the pocket thereby separating the movable contact from accidental'contact with the stationary contact I of the lamp switch.

When the testing switch is closed or on, the lamp circuit and the testing circuit are in series with :thelamp switch closed, and by contacting '-the bare ends 22 and 25 of the testing wires into Ia circuit to be tested, if the connections are correct: and'completed the lamp will remain illumined. If the equipment being tested is not in operating condition, the lamp circuit will be interrupted and consequently the lamp will be extinguished, to indicate the unsatisfactory condition of the electrical equipment being tested.

If desired the two cords or testing wires may readily be detached'from the flashlight for sole use of the latter, and with equal facility the cords may beattached when desired, for testing purposes.

Having thus fully described my invention, what 4 I claim as new and desire to secure by Letters Patent is:

In a combined flashlight and electrical testin appliance the combination with a metal casin and its inner insulating jacket and a light bulb socket mounted in one end of the casing, batteries positioned in the casing with a central terminal of one of the batteries positioned in the casing for engagement with the terminal of a light bulb in the socket, of a metallic housing divided into two compartments mounted on the casing and inner insulating jacket, a lamp circuit head forming the fixed contact point of the lamp switch mounted inone compartment on said insulating jacket and having a movable contact switch in the second compartment fixed to the REFERENCES CITED The following references areof record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,852,190 Roe Apr. 5, 1932 2,231,660 Carlotti et a1. Feb.'11, 1941 2,275,696 Stamps Mar. 10, 1942 2,302,248 Olson Nov. 1'7, 1942 2,324,661 .Woodington July 20, 1943

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US1852190 *Nov 10, 1928Apr 5, 1932Nathaniel RoeSearch-light testing attachment
US2231660 *Nov 15, 1938Feb 11, 1941Charles J CarlottiElectrical circuit exploring tester
US2275696 *Aug 1, 1940Mar 10, 1942Samuel C StampsFlashlight tester
US2302248 *Jun 11, 1941Nov 17, 1942Olson Axel VCombined flashlight and electric circuit tester
US2324661 *Aug 24, 1940Jul 20, 1943Woodington William ECombination flashlight and testing device
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2620379 *Mar 15, 1951Dec 2, 1952Zimmerman Philip LCircuit continuity tester
US2681433 *Dec 31, 1952Jun 15, 1954Thomas S PalmerFlashlight type fuse tester
US3014123 *Jul 9, 1958Dec 19, 1961Bright Star IndWarning unit and flashlight for energizing same
US3737650 *Jul 18, 1972Jun 5, 1973Mallory & Co Inc P RDisposable flashlight
US4298919 *Sep 5, 1979Nov 3, 1981Tokyo Kogaku Kikai Kabushiki KaishaLamp house structure for illumination devices
US4364103 *Aug 11, 1980Dec 14, 1982Harshbarger Thad LBattery case for an electrically operated device
US5406207 *Nov 15, 1993Apr 11, 1995Shershen; Eugene D.Electrical continuity tester combined with flashlight and/or lantern
US7416311Apr 27, 2005Aug 26, 2008Dietz Dan LFlashlight
US20060245183 *Apr 27, 2005Nov 2, 2006Dietz Dan LFlashlight
U.S. Classification324/506, 362/310, 362/396, 362/205
International ClassificationF21L4/00, G01R31/02
Cooperative ClassificationF21L4/005, G01R31/026
European ClassificationG01R31/02C4, F21L4/00P