US2258074A - Flashlight - Google Patents

Description

Oct. 7, 1941.

N. H. swANso'N FLASHLIGHT Filed June 12, 1959 Patented Oct. 7, 1941 UNITED STATES PATENT OFFICE FLASHLIGHT Nels H. Swanson, Chicago, Ill. 7

Application June 12, 1939, Serial No. 278,690 Claims. 01. 240-4058) Fig. 1 is a side view in perspective showing. a flashlight embodying this invention.

Fig. 2 is an axial section of the in open circuit position.

Fig. 3 is a. sectional view taken axially like- Fig. 2 and showing the parts in circuit-closingv position.

Fig. 4 is a transverse section taken as indicated at line 4-4 on Fig. 2.

Fig. 5 is a front end view of the lamp and its associated mounting spring removed from the.

casing.

Fig. 6 is a side elevation partly in section showing a modified form of easing fora flashlight of this type. I 1

The construction embodying this invention is particularly adapted to extremely small portable flashlights dimensioned to be carried in the pocket or in a ladys handbag, but it willbe evident that the same type of design would be applicable to larger sizes. As shown in Figs. 1 to 4, the shell, I, is of tubular form, having a reduced portion, 2, at one end, with a lightemitting aperture, 3, in its end wall, and with a shoulder, 4, at the point where the diameter is reduced. At the other end the casing'is formed with threads, 5, for connection with the threaded portion, 6, of a removable cap, I. The drycell battery, 8, is disposed in the larger portion of the tubular shell, I, with its central'contact element, 9, presented toward the reduced end portion, 2, of the shell.

This reduced portion, 2, houses an electric lamp, II], which may be of the type having a glass body formed with a lens portion, II, at its tip for intensifying the light emitted from the lamp filament. The threaded metallic base,

I2, is carried by a coil spring, I3, whose coils.

at one end are of such diameter that the flashlight taken on a larger scale and showing the parts threaded base of the lamp can be screwed into the coils of the spring which thus serve as a.

socket for the lamp. The smaller coilsof'the spring, I3, are continuous, with two or three turns, I4, of larger diameter dimensioned to fit the inner diameter of the tubular body, I,.and

to seat against the shoulder, 4, which divides;

the larger portion of the tube from the smaller end portion, 2. Finally, of the spring may be of somewhat smaller diameter than the turns, I4, so as to seat against the end wall of the battery, 8. As seen in Figs. 2 and 3, the coils, compressed and thus support the smaller coils of the spring, I3, centrally within the reduced terminal portion, .2, of tact therewith, and support the lamp itself with its tip portion, II, centered with respect to the light-emitting aperture, 3, but out of contact with the rim .of the aperture. Thus, any shock experienced by the shell, I, is transmitted to the lamp. itself only through the resilient coils oi the supporting spring, and such largely absorbed by the spring, I3, I4, I5. I

The removable cap, I, carries a spirally coiled spring, I1, which contacts with the end wall of the battery, 8. This portion of the battery is an exposed metal surface which serves as the other terminal or electrode. The cylindrical .side wall of the battery may be exposed to the metallic shell, I, or it may be covered with a paper label which would act as insulation. But contact of the spring, the battery insures completion of the circuit through the tubular shell, I, and spring, I3, when the center contact, I6, of, the lamp is engaged with the center contact, 9, of the battery. The flexible nature of the spiral spring,

I'I, permits this to be accomplished very simply by pressure .of the finger upon the spring, 11,

which forces it inwardly so that it assumes a form somewhat like that shown in Fig. 3, sliding the battery, 8, longitudinally in the shell, I, to bring its terminal, 9, into contact with the part, It, of the lamp. This movement takes place in opposition to the. coils, I5, of the spring, I3, compressing them so that upon release of the finger pressure at I1 the coils, I5, expand and separate the contacts, 9 and IE, for extinguishingthe light.

The spiral formation of the spring, I1, is con-' venient also in that the outer coil may be made slightly oversize as compared with the internal diameter of the cap, I; thus, when the coil is oneor two turns, I5,

I4 and I5, are somewhat the shell but out of con-.

shocks will be H, with the end wall of spiral for shifting the battery longitudinally in the casing to engage said center contacts.

5. In an electric flashlight, a tubular casing, a battery in the casing, a lamp bulb inside the casing having a center contact and a threaded base, the casing having a central light-emitting opening at one end and smaller than the diameter of the lamp and a transverse shoulder facing away from that end and spaced therefrom, the battery having a central contact element, and cushioning means supporting the lamp comprising a coiled wire spring having coils at one end to fit the threads of the lamp base and additional coils 10 normally holding the center contacts of the lamp and battery apart.

NELS H. SWANSON.

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