US 1392165 A
Description (OCR text may contain errors)
H. L, HUNTER. l
APPLICAHON HLED FEB. I8, |921.
1,392,165. Pat-enfedsept. 27,192.1.
gwuc 1 :for
1205er? L Hunier;
entren stares- PMENT OFFICE.
Application filed February 18, 1921.
To all whom t may conce/ML.'
Be it known that I, ROBERT L. HUNTER, citizen of the United States of America. residing at Norfolk, in the county of Norfolk and StateI of Virginia, have invented certain new and useful Improvements in Flashlights, of which the following is a specification.
My invention relates to the construction of flashlights, searchlights, spotlights, or similar devices in which electric lights or other lighting means are used.
The object of' this invention is to increase the efficiency and usefulness of searchlights ata small cost and without the us'e of complicated yor easily injured parts. By the use of my invention, -the point on which the l light from a flashlight may be effectively focused may be changed within reasonable distances without moving the flashlight itself, by varying the distance of the lens .from thelight. The usual type of electric flashlight has an incandescent light, a concavel reflector* placed back of the light,and a lens usually plano-convex in front of the light. As the light passes through the lens it is retracted; and since the lens is commonly placed close to the source of light` the emerging rays are widely dispensed and light up a relatively large area a short distance in front of the flashlight. A further object of my invention, therefore, is to make it possible to reduce when desired the diamef ter of this lighted area and to focus the light on a small area removed 'from the end of the flashlight, without changing the location of the light, but by changing the relative locations of the light and the lens.
With the usual type of flashlight, if an object to be examined in the dark is a foot or two from the light end of the flashlight,
the object is thoroughly illuminated; hut if it is at a greater distance, the illumination is diffused and consequently the light is indistinct.V By theuse of my invention the light from a flashlight may loe-focused near the end of the flashlight, at a considerable distance from the end of the flashlight, or at any intermediate point.`
With these and further objects in view, l. have illustrated an embodiment of myinvention in the accompanying drawings, in which,
Figure 1 is a side elevation of my im- Specification of Letters Patent.
Patented Sept. 27, 192,1.
Serial No. 445,922.
proved flashlight, with the lens holding part 1n section; I
Fig. 2 is a vertical sectional View of a part of the light end of my flashlight; i
Fig. 3 is a sectional view on the line 3 3 of Fig. 2;
Fig. 4 is a diagrammatic illustration .of the principle on which the form of flashlight operates;
conventional Fig. 5 is a diagrammatic illustrationof'- the principle on which my flashlight opcrates; K
Fig. 6 is another diagrammatic illustration of the principle on which my flashlight operates.
-The cylindrical case ll of the flashlight for the battery generally used, which is not shown, has a screw cap 2 on the rear end and a long screw threaded .cap 3 on the front end of the case which of course is also screw threaded. There are the usual conventional parts of a flashlight comprising a switch button 4, an incandescent light 5, reflector 6, and lens 7.
The cap 3 is made long and screw threaded in order that the lens in the end-of the cap may be placed awa-y from the light as illustrated in Figs. 5 and 6, by simply unscrewing the cap. The maximum distance the lens can he placed from the light is reached when the springs, 8 attached tothe case'l cause the points 9 thereof to enter the openings 10 in the cap 3. The cap 3 may course he removed from the case if desired, by pressing down the points 10 as thecap is screwed off.
The principle of my invention. and the means of operating it, will be apparent from the foregoing description. ,When the user of aflashlight made according to my invention, desiresto concentrate the rays of light or Vdesires an intense light at'a distance'from the front of the flashlight, he simply unl \screws the cap until the light is pro er1 focused on the object desired to be il umlnat-ed. The cap may be returned to its normal position merely by screwing it in the opposite direction. I do notrwish to rangement of parts shown, but claim the right to lall changes and modifications within the scope of my invention. 4
Having nowdescribed my invention, what he understood as limiting v myself to the precise construction and-ar- I claim as new, and desire to secure hy Letters Patent, is-
1. Means for changing the` focus of the light of a ashlight comprising a flashlight ease, a spring attached to Said case having a ypointed extension on the end thereof, a screw threaded cap for said case, and a lens carried by said cap, said cap having` an opening therein to register with the pointed extension on the end of said spring when said cap reaches a certain point onsaid case.
2. Means for changing the focus of the light of a flashlight, comprising a flashlight case, a cap for said Case, means adapted to permit said cap to travel on the said ease,
and means attached to said case and cop.
erating with said cap to stop automatically the outward travel of said cap, said means being further adapted to be manually operated to be moved to a non stop position to al W separation of said cap from said case. A
In testimony whereof I affix my signature.
ROBERT L. HUNTER.