Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.


  1. Advanced Patent Search
Publication numberUS1349392 A
Publication typeGrant
Publication dateAug 10, 1920
Filing dateFeb 18, 1918
Priority dateFeb 18, 1918
Publication numberUS 1349392 A, US 1349392A, US-A-1349392, US1349392 A, US1349392A
InventorsEdwin D Tillson
Original AssigneeAssociated Engineers Company
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
US 1349392 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

' E. o. TILLSON;



. Patented Aug. 10, 1920. :0




APPLICATION FILED FEB. 18. 1918. 1,349,392. te A11g-10J920 ,4 2 SHEETSSHEET 2. /6 A 3 A? a 1 T 22 v o 22 nnwnv-nlrrnrsolv, or oHICAGo,"I LLIIIoIs AsSIGNoR TOASSOGIATED ENGINEERS a p @GOMPANYQOF crIIcAeo,'rL-L11voIs.J-u

' LAJu -G A D.

To all whom it may concern: s I

Be itknown that I, EDWIN D TILLsoN, a citizen of the United States, residing at'Chicago, in the county of Cook and State of Illinois, have invented a certain {new and useful Improvement in Lamp-Guards, of

a I proved guard so constructed thatit prevents the failure of lamps carried therein. The

quite universal usevof' lamps having (fila- 'ments of the more breakable types, such as the tungsten type or types inwhich jars may cause contact between filament convolutions, thereby causing them to adhere together permanently, makes it necessary to; provide means for holding these lamps within guards for those places where the lamps are used,

for instance, at the extremities of extension cords or undersimilar conditions where the lamps" are subjectto violent j arsg" In order to'jprovide :a, suitable guard 'I have made many, experiments including the use of guards in which springsare used as the sole means of absorbing the shock; I find that in order to prevent breaka e of the lamp filament, "or short circuiting of said filament, by springs alone, that" 'theguar'd may be of such dimensions that it renders 1t practically undesirable, or at the very least,

V in a manner to'opposepfrictional resistance 40 renders it subject to many grave objections.

Ifind, however, that if inaddition to springshock absorbing means I alsof-arrange the lamp mounting within the guard to the movement of the lamp from ojneposition to another that I "amenabled to reduce the guardto a size within reasonable limits and still prevent failure of 'theilamp. I

find, of course, that either the frictional resistance alone or the universal spr ng mounting alone might answertoj prevent failure of the lam'p,-provided'in the case of the frictional mounting, some suitable jmeans are provided to return the lamp tQItS normal central position. In addition, I findgit desirable frequently to construct the guard framework itself resilience.-

in a manner to provide 1 -q V Specification of Letters-Patent.

Application fil mentar 1s, 191's-'.i serialiro. 217,822.

Patentedhug. n, 1920.

jnoiweva, my experimna ieaa a to be lieve that the combination of the frictional mounting andvthe spring absorbing means lsthenlnost efiective, although as before initialinovement offthe lamp is retarded by the friction duejto the frictional mounting between the relatively movable parts'and' I that the retardation, iffplotted,{in the form ofa curve would be practically a straight ,line'. The retardation offeredby the spring wouldof course be gradually increased from zero at the initial movementof'the lamp. to

thel maximum when the lamp has reached its final position of displacement. Springs cannot beused which are too strong andif the right kind of a spring-is used,' too much throw may be permitted the'larnp to bring the guard Within commercial requirements as to size.

IViththe combination of frictional retard.- ingmeans and springretardation, I am enabled to obtainahnost a straight line curve,

which will bring the lamp to a stop within a guard of'reasonabl e' size.

Y I will explain one form of carrying out my inventlon more in detail by'referring to the accompanying drawings, in which- Figure 1 isaside 'viewtQfa guard conl 2 is a top viewthereof;

structed in accordance with my invention;

' F1g.3 is anenlargedigfragmentary View similar to that of Fig; 1, c'ertain parts being shown in sectionniore clearly to reveal features of construction;

Fig.1 4; is a side view partly in section similar to the view ofF 3 but showing a modified form of the invention in which my improved guard is already in-i1se; j V j 7 Fig.5 is a fragmentary sectional view'on line 5-5 of Fig. 4. I

applied to a socket Referring more particularly to Figs l, 2

and 3, my improveddevice includes an'electrio IZLmPISOCkQt '10, the shell ofwhich-htrs an outwardly flaring upwardly projecting spherical extension 11. The spherical extension 11 cooperates witha fragmentar spherical element 12 frictionally held by the q i throughthe hollow elements 11, 12 and 13 j cap 13. The cord His shown projecting directly into the socket 10. The cap 13, through the agency of the nut 15 is frict1onally secured to the pan shaped plate 16. T his plate 16 hasaplurality of guard arms 17. fastened thereto and extending downwardly therefrom so as to encircle the lamp 18 carried by the socket 10. The arms 12 preferably have their extremities united by a ring herein contemplating four springs 23 but eight arms 17. There is preferably no connection between the elements 11 and 12 other than frictional and these parts are held 111 their frictional engagement due to the ten-' sion of the springs 23, these springs pulling these parts 11 and 12 together and exerting a pressure so that there is a certain amount of friction between the elements 11 and 12, which friction tends to retard relative movement between these elements 11 and 12.

The mode of operation of the device will thus be apparent. If the guard together with the lamp is dropped or given any ar, then the lamp 18 will of course move away from its central pdsition and immediately occupy the position as shown by dotted lines in Fig. 1. This movement of the lamp from the central position is retarded by the friction between the elements 11 and 12, this frictionbeing proportional to the strength of the springs 28. Eitthe first initial movement of the lamp the springs 23 do not exert a very great retarding influence. The frictional retarding influence however is quite constant. As the lamp moves farther away from its central position the retarding influence of the springs becomes stronger until finally the lamp is brought to rest without any serious jar. Ears 30 are provided to prevent more than a predetermined amount of rotation of the lamp socket when inserting or withdrawing a lamp. The construction of the guard is such that its upper restricted portion serves as a handle, and that its lower wide-open mouth permits it to stand on the fioor or table as may be desired.

in Figs. 4 and 5, T have shown a modified form in which the element 11 is the cover plate of the element 11 in Fig. 3 with the eX- ception that it has a downwardly extending hood 2a which is split and which may be frictionally mounted upon a socket 25 of the standard type and held in place by means re eases 2.1-1 lamp, guard having a movably V mounted lamp support therein, frictionalretarding means tending to oppose-the movement of said support, and springs connecting the guard to the support to maintain said support in a central position and'control the friction of said retarding means.

3. A lamp guard having a movably mounted lamp support therein, frictional retarding means tending to oppose the movement of said support, resilient means connecting the guard and support for controlling said frictionv means, and means to prevent rotation of said support.

4. A lamp guard having a movably mounted lamp support therein, frictional retarding means tending to oppose the movement of said support, and fingers forming part of said support and adapted to surround said lamp.

5. A. lamp guard having mounted therein frictionally controlled means for yieldingly holding a lamp, fingers forming part of said frictionally controlled means and surrounding said lamp, and resilient means connecting said frictionally controlled means to said guard for controlling the movements of said frictionally controlled means.

6. A lamp guard having a movably mounted lamp support therein, frictional retarding means tending to oppose the movement of said support, resilient means for controlling said frictional means, and fingers on said guard and adapted to surround said lamp, said resilient means connecting the guard to the fingers.

7. A device of the character described comprising a plate member, a cap secured thereto, a spherical element contacting said cap, a socket, an extension on said socket for engaging the spherical element and resilient means for holding said parts in frictional contact. 7

8. A lamp support comprising a frame, a cap secured to said frame, a socket, a loose frictional element interposed between the cap and socket, and springs connecting the socket to the frame, for holding said parts in frictional contact.

1,349,392 f 1 i v ,'p

9 A lamp support coinprisihga frame, a Within the framework and hearingflagainst 15,

Ilamp socket within the frame; fingers se one portion thereof, andsprings'connecting cured to said socket and adapted to'sur the socket to the framework. 2

round a lamp in said socket and springs-v 12. A; device of thecharacter described connecting the frame tosaid'fingersr 1 having a frame, a lamp support mounted 10. A lamp holding device comprising a within the frame, frictional retardingmeans 20 frame, a movable socketwithin said frame tending to oppose movement ofthe. support and having frictional contact with thewithin theframeand springs connecting the i 7 frame so that its movements in the frame support to the frame.

are retarded thereby, and springs connecting n witness whereof, I hereunto subscribe the socket to the frame and tending to move my 'name this 28th day of December, A; D. 25

the socket upwardly'inthe frame. 7 1917-. m r I 1 11. A lamp holding device havlng a yieldable framework, a socket yieldably mounted M EDWIN TILL SON.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2750488 *Apr 8, 1953Jun 12, 1956Mcgraw Electric CoSwivel marker for elevated runway fixtures
US5902037 *Feb 3, 1997May 11, 1999Holmes Products Corp.Lamp with safety features
US6217199Nov 19, 1999Apr 17, 2001The Holmes Group, Inc.Lamp with safety features
U.S. Classification362/377, 362/378
International ClassificationF21V15/02, F21V17/00
Cooperative ClassificationF21V17/00, F21V15/02
European ClassificationF21V17/00, F21V15/02