|Publication number||US2218678 A|
|Publication date||Oct 22, 1940|
|Filing date||May 6, 1938|
|Priority date||May 6, 1938|
|Publication number||US 2218678 A, US 2218678A, US-A-2218678, US2218678 A, US2218678A|
|Inventors||Allan C Hoffman|
|Original Assignee||Scovill Manufacturing Co|
|Export Citation||BiBTeX, EndNote, RefMan|
|Referenced by (9), Classifications (11)|
|External Links: USPTO, USPTO Assignment, Espacenet|
Oct. 22, 1940.
A. c. HOFFMAN Filed May 6, 1938 2 Sheets-Sheet 1 I III: Z0
all 1 ML A.
3nnntor (Itto mags.
I e 1 present relates to land I Patented Oct. 2 2,
rnoreparticularly to those of the mu1ti 1ergcus- ;ing type,
Another object is to prov1 light source being relatively adjustable to dispose the light source at the focal point of either one of the reflectors independently of the other reflector so that the light rays from the light source will be reflected from but one reflector at a time.
A further object of the invention is to provide in a flashlight large and small parabolic reflectors of highly polished and mat surface constructions with a light source, the reflectors and the light source being disposed coaxially for relative adjustments to obtain by a slight movement the individual effects of the reflectors, the arrangement being such that the advantages are attained in a relatively simple and compact flashlight structure. l
Another object of the invention is to provide a flashlight construction embodying a spotlight of relatively large size and intensity and from which is eliminated all lateral rays so as to obtain the advantage of all of the light rays for the spotlight.
A still further object of the invention is to provide a construction of flashlight using inner and outer independent parabolic reflectors with the inner reflectorhaving a mat surface and the outer larger reflector having a polished surface, the reflectors-being arranged with respect to a light source such that the rays of light from the light source when the latter is focused in one of the reflectors cannot strike or impinge the surface of the other reflector so that the entire lighting effect of each reflector is independently'obtained upon a relatively small adjustment of the light source from the focal point of one reflector into the focal point or center of the other reflector.
With the foregoing and other objects in view, the invention will be more fully described herein after, and will be more particularly pointed out in the claims appended hereto. In the drawings; wherein like symbols refer to Y. aziatzs .RE L l Ammo.-ntemaniwaer h i; count saint:
- scoviu Manufacturing Oompany;-' Wate pur y ,wCon'nt'a corporation of-Oonnecticu tobject: of the invention is toprovide a flashbOdY' light capablelof adjustment in one position to. project a' mild flood light with a substantially uniform field of light intensity devoid of; lightrings f and capable, of adjustmentinto another position a to project a relatively large bright spot. light of can. nd qr t ine l b J 3 .ur 1 in a ju'st'ed qa't the focal enter oi the inner smaller 7 e; a flashlight withv .a small mat surface parabolic'reflector .independi r out ar largercoaxialpolishedparabolic reflector 1 u and with alcoaxial light source; the reflectorsand it .the light; source 1 a of, the outer refle we e estamentar ,Qn aI dJQnatudin I 1 section taken substantially. centrally through the m ht subst ntially :Qnrthe h r htisoumerbei s Figure} is a view lmilarto Figure tbutiwith djusteddntoi-the foc center a Figure 4 efimnwetseswflvuta en thro the upper or outer end of the head of the 'flashl light on substantially the line 4-4 of Figure 3.
Referring now to the drawings, I 0 designates the casing of a flashlight which is provided with 'ing the same and holding one or more batteries 12 in the casing ID in the usual manner. The outer end of the casing III has an end wall [3 which carries in insulated relation thereon a battery contact I4 provided with a spring contact tongue l5 which projects at the inner side of the wall 13 toward one side of the casing, I0; shown clearly in Figures 2 and 3. The central contact of the adjacent battery l2 engages the contact I 4 on the wall and the opposite side of the battery I2 is closed through the casing"! and through a suitable switch mechanism which cooperates with the spring tongue contact l5 for closing the light circuit.
A slide Hi is mountedin one side of the casing I 0 and has its lower portion connected to a thumb piece I! which is slidably disposed against the' outer side of the casing l0 and provided with inwardly extending flanges l8 projecting through a.
longitudinal slot l9 in the side of the casing Ill The lower end of.the slide I6 is suitably secured to the flanges l8 so that shifting of the thumbpiece I! will move the "slide I6 longitudinally in the casing. The slide I6 is provided with a spring contact tongue 20 at its inner side adapted to engage the contact tongue I5 when the slide it is moved outwardly or upwardly within the casing into its first focal position, shown in Figure 2. The slide I8 is in electrical communication with the casing i0 and the battery i2 through the thumbpiece I1 and is also in electrical communication with'the shell of a lamp socket 2| carried by the slide coaxially with the casing Hi. The lamp socket 2| is adapted to receive an electric lamp 22 therein which provides the light source of the flashlight. The central contact of the lamp 22, when the latter is in the socket 2|, is in electrical communication with the inner portion 23 of the slide and the latter is insulated from the body portion of the slide in any suitable manner, as shown, and the spring contact 28 is carried by this insulated portion of the slide. The circuit is thus closed through the battery contact |4, spring tongues l5 and 28, the conductor strip 23 of the slide to the central contact of the lamp 22 and back through the lamp socket 2|, body portion of slide i6 to the casing and opposite side of the battery |2. The slot [9 in the casing i8 is proportioned in length to the desired distance through which the slide I6 is adapted to be shifted, The slide l6 when fuly retracted withdraws the spring contact 28 from the contact l5 so as to break the circuit. The initial movement of the slide I8 is to close the circuit, as shown in Figure 2 and advance the light source 22 into the focal center of an inner parabolic reflector 24 which has an opening at its center of suiiicient diameter to freely receive the lamp 22 therethrough The reflector 24 is provided with a mat or light diffusing surface and has an annular rim 25 of substantially cylindrical form terminating at its outer edge in an outturned flange 28. The
rim 25 is adapted to flt snugly through a central opening provided in a screw cap' 21 while the flange 26 is adapted to overlap the outer surface of the cap 21 so as to limit the inward movement of the rim or circular band 25 through the cap. The rim 25 and the flange 28 thus'determine the position of the inner reflector 24 and the cap '21 is so mounted and supported as to hold the reflector 25 in a desired axial position in the flashlight with respect to the primary focal adjustment of the light source 22.
The flashlight is provided with a head 28 of any suitable construction and configuration, and which in the present instance is shown as of hollow shell form. The head 28 is provided with an internal threaded sleeve 29 coaxially disposed in the head and extending from the inner end thereof outwardly or toward the outer end of the head. The cap 21 is threaded into the outer end of the sleeve 29 and may thus be adjusted axially of the flashlight upon the sleeve 29. The inner end of the sleeve 29 is threaded upon the outer end of the flashlight casing N and may be turned up upon the same to the desired extent for shifting the head axially on the casing and moving the reflector 24, and other parts of thehead into the desired adjustment relative to the light source 22.
The head 28 also carries an outer and larger reflector 38. The' reflector 38 has a highly polished light reflecting surface to provide a large and intense spotlight. The outer edge of the reflector 38 is provided with a rim flange 3| against which may be seated a lens 32 of any suitable construction and which is provided with an outer marginal beveled edge adapted to fit in the central opening in the outer end of the cap 28, as shown in Figures 2 and 3. The cap 28 and other parts of the head and reflector 38 are so proportioned that the lens 32 is clamped in the opening of the head 28 by the reflector 30 when the adjustable cap 21 is advanced outwardly in the head sleeve 29 to bind the rim 25 of the inner reflector against the inner end of .the outer reflector 38. The outer reflector 38 has an enlarged central opening which is of less diameter than the internal diameter of the rim 25 of the inner reflector so that the outer edge of the latter may engage and bind against the outer surface of the reflector 38 near its inner end to hold the reflectors 24 and 38 in coaxial aiinement, and also to provide an inwardly extending annular lip 33 which overhangs the surface of the reflector, 24 to intercept any rays reflected upon the rim 25 which would strike the surface of the outer reflector 3| when the light source 22 is in its initial position, as shown in Figure 2, or which would be projected from the light source when in its outermost position, as shown in Figure 3, upon the inner reflector 24.
The slide I8 is adapted to be shifted outwardly from the position shown in Figure 2 into the position shown in Figure 3, wherein the light source 22 is at the focal center of the outer reflector 38. At this point, shown at the section line 44 of Figure 3, a light source 22 is advanced out of range of the inner reflector 24 so that practically no light rays are projected upon the inner reflector and consequently any rays from the inner reflector cannot affect the spotlight rays which are projected from the outer reflector 38. light source 22 is retracted into the reflector 24, at the focal center thereof, as shown by the line 34 in Figure 2, the light rays from the lamp 22 will be diffused and reflected from the mat surface of the inner reflector 24 to provide a mild field of light within the range of lens 32 and, as the light source is out of range of the outer reflector 38, there will be no concentric light rings, or the like, projected upon the diffused light field when the inner reflector is used. Thus the flashlight may b'eadjusted to provide a light field of moderate intensity but which is uniform throughout and unaffected by any bright polished surface reflections. The lip 33 may of course be proportioned according to the characteristics of the reflector mounting, and relative to the depth of the cylindrical rim 25 so as to obtain the desired results, and substantially completely isolate the reflectors as regards their individual light effects. By this construction the full light intensity value of the light source 22 is obtained for both the diffused light field and the spotlight. The spotlight reflector 38, being the larger reflector, produces a relatively large and intense spotlight which is not materially detracted from by the relatively largecentral opening through which the diflused light rays from the inner reflector 24 may pass.
Thus, by a flashlight structure of this character the slight axial adjustment of the light source provides a complete and independent diifused light projection for a uniform flood light or a large and intense spotlight without interfering projections from the mat surface reflector. This substantially complete isolation of the reflectors relative to each other has an individual lighting effect as above particularly described and which, while sought after, has not heretofore been accomplished in any composite flashlight structure. The adjustable feature of the flashlight is thus made more positive and certain and the flood It will also be noted that when the I i Q aeraevs that in the use of the flashlight the slide II is normally retracted so as to withdraw thelamp 22 backwardly or inwardly out of the focal range of the inner reflector 24. This position also spaces the spring contacts l5 and 20 so that the light circuit is broken. When it is desired to use a flashlight the thumbpiece I1 is first advanced into the initial and focal position shown by the line 34 in Figure 2. Here the source of light 22 is at the focal center of the inner reflector 24. As the inner reflector has a mat surface, the light rays are diffused and are projected forwardly through the opening in the center of the outer reflector 30, without striking the same, and are thus projected through the lens 32 to provide an even and modified flood light or light field which is spread over an area sufllcient within the range of the flashlight.
When a desired object or point of the light fleld is located, the thumbpiece l1 may then be slid forwardly or outwardly to advance the lamp 4 22 into the outer focal position, shown on the section line 4-4 of Figure 3. In this position the source of light has .been moved entirely out of the inner reflector 24 and is now located at the focal center of the outer reflector 3 0. The outer reflector 30 has a high polished reflecting surface so that a brilliant spotlight of large fleld area is projected from the flashlight. The cylindrical rim 25 is substantially covered by the overhanging lip 33 so that the spotlight is not interrupted by any lateral light rays projected from the inner reflector 24.
The flashlight may be quickly and easily adiusted into the flood or spotlight positions as the positions are definitely determined by observing the lighting effects during the shifting of the light source from one focal position into the other. Of course the casing and structure may be provided with any suitable means for determining the two focal positions, and also the circuit open position. All of the adjustments are effected from a single thumbpiece by merely sliding the 7 same into different positions, and the simplicity that if desired the inner reflector 24 may be provided with the highly polished reflecting surface while the outer larger reflector 30 may have the mat light diffusing surface. This arrangement would not disturb the arrangement between the light source 22 which is adjustable into and out of the focal centers of the reflectors, and wherein the reflectors are shielded against the reflections which otherwise would pass betweenthe reflectors and tend to disrupt or disto obtain a flood light from the inner reflector and a spotlight fromthe outer reflector, and shielding means disposed between the reflectors to intercept light rays from the light source in either focal position tending to strike the reflector of the opposite focal position.
2. In a flashlight, a casing having a head thereon; inner and outer reflectors mounted coaxially in the head with their focal centers spaced axially apart a substantial distance, one reflector having a mat light diffusing surface and the other reflector having a highly polished light reflecting surfaces, a light source adjustably mounted in the head for movement into independent focal adjustments with respect to the inner and outer reflectors, whereby to obtain either a flood light or a spotlight, said outer reflector having an inner part projecting into the inner reflector a substantial distance to constitute shielding means disposed between the reflectors to intercept light rays from the light source in either focal position tending to strike the reflector of the opposite focal position. 1
3. Ina flashlight, a casing having a head thereon, a pair of independent. reflectors coaxially spaced apart within the head, the inner reflectorbeing small and having a mat light diffusing surface and the outer reflector being larger and having a polished light reflecting surface, a slide mounted on the casing and projecing into the head, a source of light mounted on the slide in the head coaxially with the reflectors, and circuit closing means including the slide for energizing the source of light and adapted to break the circuit thereof when the slide is fully retracted, said slide adapted to be advanced outwardly toward said head for flrst closing the light circuit through the source of illumination and adapted to beadvanced consecutively into the focal centers of said reflectors for first projecting a flood light and subsequently projecting a large relatively brilliant spotlight from the flashlight.
4. In a flashlight, independent coaxial spaced apart, large and small reflectors facing in the same direction, the larger reflector having an axial opening of sufficient =-diameter to admit passage therethrough of light rays reflected from the small reflector, one reflector having a polished light reflecting surface and the other reflector having a mat light diffusing surface, the focal centers of said reflectors being axially spaced apart a substantial distance, a light source coaxial with the reflectors, movable supporting means for the light source to move the same from the focal point of one reflector into the focal point of the other reflector and quickly change the character of the projected light fleld for adapting the flashlight to the illumination desired, and movable switch means for controlling the illumination of. the light source coupled to said supporting means adapted to cause movement of the supporting means with said switch means.
5. Ina flashlight, a casing having a head shell, a pair of independent reflectors mounted in the head shell in coaxial alinement, with the outer reflector having an opening at its inner end through which reflected light rays from the inner reflector may pass, the focal centers of said reflectors being axially spaced apart a substantial distance, a light source, a movable support for the light source for moving the same from the focal point of one reflector into the focal point of the other reflector, and switch means movably mounted in said casing for controlling the ilwave.
lumination of said light source and having comnection to said support adapted to cause the support to move with said switch means.
6. In a flashlight, a pair of parabolic reflectors axially spaced apart, one reflector being small and the other reflector being large with an opening at its central portion through which projected light rays from the small reflector may pass, the focal centers of said reflectors, being axially spaced apart a substantial distance, a source of light, switch means movably mounted on the flashlight for controlling the illumination oi. said source of light and means moved by said switch means for relatively moving the source of light 5 and the reflectors to shift the light source from one focal point to the other.
ALLAN C. HOFFMAN.
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US3184591 *||Jul 19, 1957||May 18, 1965||Cibie Pierre||Projectors, more particularly motor vehicle headlights|
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|US3936670 *||Oct 29, 1974||Feb 3, 1976||Allen Sr Harry Emitt||Portable light|
|US5424927 *||Sep 2, 1993||Jun 13, 1995||Rayovac Corporation||Electro-optic flashlight electro-optically controlling the emitted light|
|US5560705 *||Dec 12, 1995||Oct 1, 1996||Shiau; Shoei-Shuh||Multi-function lighting device|
|US9066777||Apr 1, 2010||Jun 30, 2015||Kerr Corporation||Curing light device|
|US9072572||Jun 21, 2013||Jul 7, 2015||Kerr Corporation||Dental light device|
|US20150043191 *||Jul 17, 2014||Feb 12, 2015||Osram Gmbh||Lighting apparatus with zooming function|
|DE3523005A1 *||Jun 27, 1985||Jan 8, 1987||Sassmannshausen Knut||Flat pocket lamp having a concave mirror reflector and cells arranged juxtaposed for the purpose of power supply|
|International Classification||F21V19/02, F21Y101/00, F21V13/00, F21L4/00|
|Cooperative Classification||F21L4/00, F21V19/02, F21L7/00|
|European Classification||F21V19/02, F21L7/00, F21L4/00|