Flashlight

[57] ABSTRACT

A flashlight including a bulb and an electric power source preferably in the form of a battery of seriesconnected cells within a casing having a cover, one terminal of the battery being in permanent electric connection with the center contact stud of the bulb of the flashlight via a resilient blade welded or soldered to the metal can of one of the cells which can constitute said terminal of the battery. The second terminal of the battery constituted by the center stud of another of the series-connected cells is connectable at will to the base of the bulb by deformation of a second resilient blade through the agency of a movable control means. In order to insure accurate positioning of the second blade and reliability of contact of one of its extremities with the said cell center stud on appropriate movement of the control means and reliability of contact of the other extremity of said second blade with the base of the bulb, the second resilient blade is fastened securely and permanently to an inner surface of the cover so as to position and provide proper location of the two extremities relative to said cell stud and bulb base.

Claims, 3 Drawing Figures

<img file="US3758773A_D0001.tif" />

PATENTEOStfl 11913

3.758.773

<img file="US3758773A_D0002.tif" />

<img file="US3758773A_D0003.tif" />

<img file="US3758773A_D0004.tif" />

3,758,773

FLASHLIGHT

RELATED APPLICATIONS

A related application entitled “Pocket Flashlights” Ser. No. 225,484, filed Feb. 11, 1972 whose applicants are Antonio Bigliardo and Elie Sennelier is now abandoned.

BRIEF SUMMARY OF INVENTION

The invention relates to flashlights of the type comprising an electric power source such as a dry cell or an electric battery of series-connected cells and an electric bulb assembled in a common sealed housing embodying a container and cover sealed thereon, the central stud of the bulb being maintained in permanent electric connection with a preferably resilient metal blade secured as by soldering or welding to the metal can of one of the cells of the battery, said can constituting one of the terminals of the battery. One extremity of a second resilient metal blade is in electrical connection with the conductive base of the bulb and the other extremity of said second blade is applicable by movement at will of a control means into contact with the second terminal of the battery to complete the electric circuit through the bulb and then cause its illumination.

Flashlights of such general type have already been described in said copending application.

In that application, the second metal blade constitutes an integral part of a small plate that is in permanent contact with the base of the bulb.

In one of the embodiments disclosed in said copending application, the battery comprises a plurality of series-connected cells so disposed that the second terminal of the battery against which an extremity of the second metal blade is caused to be applied for completion of the current circuit through the bulb is the center stud constituting the positive pole of one of the said cells. The second blade is integral with a small metal plate secured to a throat in the cover which supports the base of the bulb.

A delicate problem to be solved with such flashlights has been found to be the, need for reliability of the contact to be effected between the said extremity of the said second metal blade and the said positive stud of said one of the cells.

Indeed, in view of the small size of this stud, it has been found that if the small metal plate of which the second metal blade is part is inaccurately positioned about the throat in the cover or that the arching or bending of the various parts of the second blade is done poorly or inaccurately that reliable circuit-closing contact between the said stud and the said extremity of said second blade can fail to be effected satisfactorily. Thus, there is likelihood of failure of illumination, or irregular or weak illumination of the bulb.

Thus, such an arrangement requires very high precision in assembly and furthermore requires the prior fastening, for instance, by soldering or welding of an elastic contact blade to the can of a cell. It also requires separate manufacture of the small metal plate and second blade integral therewith followed by proper installation of the metal plate in proper position on the throat and in secure contact with the base of the bulb.

An object and feature of the present invention is to effect simplification of manufacturing and assembly operations in the production of flashlights and also to render it possible to eliminate need for detached parts such as the small plate of the aforesaid co-pending application.

Another object and feature of the invention is the provision of a flashlight comprising a casing including a cover provided with a receptacle for a bulb, an electric power source such as a battery positioned within said casing, a first terminal of which is in permanent electrical contact with the center stud of the bulb and including also an elastic and conductive blade that is in electric contact with the base of the bulb and an extremity of which under the effect of a movable control means may be shifted into accurate reliable contact with the second terminal of the power source, and wherein further, fastening means are provided for maintaining the said blade secured against a bearing surface within said casing situated in proximity to the said bulb receptacle.

In a preferred embodiment, the said fastening means constitutes an integral part of the said casing.

In a first particular embodiment, the said fastening means comprise at least one rivet-like element projecting from the said bearing surface through a hole provided in the blade and headed over in rivet-like manner over the surface of the blade opposite that which is applied against the said bearing surface to maintain the blade secured to said surface.

According to another embodiment, the said fastening means may comprise at least one rivet traversing the blade and secured to the cover portion of which the bearing surface is a part.

According to another variant, the said rivet may be replaced by a screw.

Preferably, the bearing surface includes at least along one side an upstanding edge which is engaged by at least one edge of the blade to prevent rotation of the blade after its attachment on said bearing surface.

In another embodiment, the said fastening means are provided by upstanding parallel edges at opposite sides of the bearing surface that subsequent to positioning of the blade or said surface are bent back or turned over at least in part over the surface of the blade opposite that which has been applied against the said bearing surface, thereby providing the said fastening means.

According to an embodiment of the invention, the casing comprises a container and a cover, the said bearing surface being provided in the cover.

Other objects, features and characteristics of the invention will become apparent from the following description of embodiments presented as non-limitative samples in conjunction with the accompanying drawings in which:

FIG. 1 is a partial cross-sectional view of a flashlight embodying the invention;

FIG. 2 is a partial cross-sectional view taken along line 2—2 of FIG. 1 showing only the blade and that part of the cover to which it is fastened, and

FIG. 3 is a view similar to that of FIG. 2 of a modified embodiment.

DETAILED DESCRIPTION

Referring to FIG. 1, the flashlight comprises a container 1 of suitable plastic material surrounding three cylindrical cells 2,3 and 4 electrically connected in series by wires W_t and W₂ respectively in order to form a battery .

The usual center stud 5 of a bulb 6 is electrically connected to the metal can of the cell 2 via a springy metal

3,758,773 blade 7 secured in electrical contact with said can, which latter serves as the negative terminal of the battery.

A cover 8 of plastic material similar to that of said container is mounted on and sealingly secured to the container 1 in order to provide the sealed flashlight casing. This cover has a concave upper wall 9 which in its region of maximum depth has an opening 9'. An inwardly extending tubular throat 10 preferably integral with the wall 9 of the cover 8 is provided at the opening 9'. The inner wall of this throat might be threaded to receive and support therein the conductive base 11 of the bulb 6. In addition, the wall of throat 10 internally of the cover and below wall 9 has a longitudinally extending notch or slit 10' to expose a small portion of conductive base 11 internally of cover 8.

The wall 9 is thickened at a portion 9 on its inner face and extends laterally of throat 10. This thickened portion 9 has a flat surface 13 (beSt seen in FIG. 2) on its innermost face. A pair of projecting ribs 14 disposed at opposite edges of surface 13 serve to define a channel 13' that extends laterally of notch or slit 10' and opens into it. A pin-like projection 15 extends outwardly of flat surface 13. In the embodiment shown in FIG. 2, this pin-like projection is integral with and of the same material as thickened wall portion 9” of cover 8. It may, however, be replaced by a rivet or screw or other equivalent fastening members.

A second resilient blade 16 is provided for completing an electric circuit between the base 11 of the bulb and the second terminal of the battery which terminal as shown in FIG. 1 is stud 17 of cell 4. This blade 16 is of springy conductive metal and provided in its length with a number of portions bent at different angles relative to each other. The blade is shown in FIG. 1 in solid line representing its “off condition when no current flows and in dotted line representing its “on” condition when the electric circuit is complete and the bulb 6 is illuminated.

In the solid line position illustrated by said figure, the electrical connection between the base 11 and the stud 17 of the cell 4, forming the positive and second terminal of the battery is open because extremity 18 of blade 16 then is spaced from said stud 17. Upon movement of the control member 19 of conventional type located in cover 8 from its full line “off” position as seen in said FIG. 1 in the direction of the arrow F, to the dotted line “on” position, its nose 19' engages portions of the blade 16 and deforms it so that its extremity 18 is then moved into contact with the stud 17, thereby closing the electric circuit to the bulb 6 via said blade 16 and causing its illumination. On reverse movement of control member 19, the resiliency bias of blade 16 restores it to the full line “off” position of FIG. 1 extinguishing bulb 6.

The extremity 21 of the blade 16 that lies in contact with the base 11 of the bulb includes a transverse ribbing 22 which projects through notch or slot 10' of throat 10 into engagement with conductive base 11 between a pair of its threads to provide a reliable and steady electrical contact with the base 11 and also to effect a locking of the bulb 6 in position in throat 10.

The blade 16 comprises adjacent its extremity 21 a flat portion 23 substantially perpendicular to the portion forming extremity 21. The rear surface of flat portion 23 in assembly is in contact with the flat surface 13 of the thickened portion 9'' of cover 8. The width of portion 23 of blade 16 is admeasured so that when said portion is mounted on said flat surface it fits between ribs 14. The pin-like projection 15 extending from surface 19 then projects through a hole 24 provided in the portion 23 of the blade and is headed in rivet-like fashion at 25 to secure the blade 16 in position on flat surface 13. The headed pin-like projection 15 and ribs 14 then hold the blade 16 securely in position and against rotation with ribbing 22 in effective electrical contact with base 11.

As an alternative as is illustrated in FIG. 3, the ribs 14α are folded over in rivet-like fashion at 146 to overlie the side edges of the flat portion 23α of the blade 16α to effect fastening of said blade 16α in position on flat surface 13α. This arrangement eliminates the need for pin-like projection 15 and hole 24 required in the first embodiment described above.

As further alternative (not shown) the pin-like projection 15 can be replaced by a rivet or a screw. Likewise, the ribs 14 or 14α can be eliminated by the use of two spaced-apart pin-like projections 15 or a similar number of rivets or screws instead of said ribs.

The various portions of resilient metal blade 16 which are bent at differing angles relative to each other include a portion 26 adjoining flat portion 23 which is bent upwardly relative to said portion 23. A portion 27 adjoining the portion 26 is bent downwardly relative to portion 26. The nose 19' of control member 19 rests on the uppermost surface of this portion 27 in the “off” position as seen in full line in FIG. 1. A portion 28 directly adjoining the portion 27 is bent downwardly relative to portion 27. A further bent portion 29 directly adjoins portion 28. Movement of control member 19 in the direction of arrow F to its dotted line position causes nose 19' to slide over the surface of portion 28 into engagement with the step-like surface provided by portion 29 so that when control element 19 reaches its dotted line “on” position, the blade 16 will have been shifted from its full line position to the dotted line position as seen in FIG. 1 at which time the extremity 18 of said blade 16 will have been shifted into positive surface engagement and reliable and intimate contact with center stud 17 of cell 4 establishing the “on” condition and illumination of bulb 6 of the flashlight. The successive bent portions 30 and 31 beyond portion 29 terminate in the extremity 18 whose flat surface provides large area for reliable contact with the surface of stud 17.

On reverse movement of the control element 19 to restore it to the full line position of FIG. 1, the resiliency bias of spring blade 16 causes its restoration to the full line condition of FIG. 1 with separation of extremity 18 from stud 17 thus breaking the circuit to the bulb and extinguishing it. Similar results occur if blade 16α described with reference to FIG. 3 is utilized in lieu of blade 16 of FIG. 2.

Chief advantages resulting from the practice of this invention are a reduction in the number of parts required to manufacture the flashlight as well as a simplification in assembly procedure. As a result, such flashlights are easier to manufacture and mush less costly. At the same time, the reliability of contacts necessary to effect circuit closing conditions to illustrate the bulb is retained.

While specific embodiments of the invention have been disclosed, variations within the scope of the appended claims are possible and are contemplated.

3,758 5

There is no intention, therefore, of limitation to the exact disclosure herein presented.