US2441929A

US2441929A - Lamp holder for fluorescent lamps

Info

Publication number: US2441929A
Application number: US550170A
Authority: US
Inventors: Guy H Burt
Original assignee: GUY H BURT; HARRY M BURT
Current assignee: GUY H BURT; HARRY M BURT
Priority date: 1944-08-19
Filing date: 1944-08-19
Publication date: 1948-05-18
Anticipated expiration: 1965-05-18

Description

May 18, 1948. G. H. BURT LAMP HOLDER FOR FLUORESCENT LAMPS.

Filed Aug. 19, 1944 2 Sheets-Sheet 1 INVENTOR: Guy H. BURT A TTOQ/VEY May 18, G H BURT LAMP HOLDER FOR FLUORESCENT LAMPS Filed Aug. 19, 1944 2 Sheets-Sheet 2 78 74 INVENTOR. Guv H. BURT A 7'TOENEY i atented May 18, i948 2,441,929 LAMP HOLDER FOR FLUORESCENT LS Guy H. Burt, Edgewood, R. I., assignor to Harry M. Burt and Guy H. Burt, doing business as The Lloyd Products Company, Providence, R. 1.

Application August 19, 1944, Serial No. 550,170

6 Claims. (Cl. 1'73328) This invention relates to lamphol'ders. More specifically, it pertains to lampholders for individually supporting and supplying power to the ends of an elongated electric illuminatin device, such as a fluorescent electric discharge lamp, by coaction with projecting pins on the ends thereof, and for short circuiting s-aid pins upon insertion of the lamp.

It is the principal object of the invention to provide a lampholder of the character described in which the short circuiting current is passed through only one of the lamp contact pins, thereby efiecting an extremely simple construction which can be made at but a slight advance in cost over that of a conventional non-short circuiting lampholder. I

More specifically, it is object'of the invention to provide a short circuiting lamp holder of the character described which operates in the foregoing fashion regardless ofthe manner in which the lamp is inserted. v

Other objects of this invention will in part be obvious and in part hereinafter pointed out.

The invention accordingly consists in the features of construction, combinations of elements, and arrangements of parts which will be exemplified in the constructions hereinafter described, and of which the scope of application will be indicated in the claims.

In the accompanying drawings, in which are shown various possible embodiments of this invention, V

Fig. 1 is a side elevational view of a pair of push-type lampholders embodying the invention, mounted on a support and cooperatively holding a fluorescent electric discharge lamp;

Fig. 2 is a front view of one of said lampholders; I

Fig. 3 is an enlarged rear view of the lamp engaging end of the lampholder with the back cover plate removed to expose the interior construction;

Figs. 4 and 5 are sectional views taken substantially along the lines 4-4 and 5-5 of Fig. 3;

Fig. 6 is a view similar to Fig. 1 of a pair 0 twist-type lampholders embodying a modified form of the invention; v

Fig. '7 is 'an enlarged front view of the lamp' engaging end-oi one of the lam'pholders shown in Fig.6 with the lamp removed;

Fig. 8 is a sectional view taken substantially along the line 88 of Fig. 7;

Fig. 9 is a rear view of the back of said lampholder with the back cover plate removed to expose the interior construction; and

Fig. 10 is a sectional view taken substantially along the line I 0lfl of Fig. 9.

In general, the foregoing objects of the invention are carried out by providing a short circuiting member which is electrically connected to one of the lampholder blades, is insulated from the other lampholder blade, and has a contact portion disposed close to but out of contact with said other lampholder blade and in such position that when the two pins at one end of a fluorescent electric discharge lamp are inserted in the lampholder one of the pins will contact both a 1ampholder blade and said contact portion, which remains spaced from said blade, whereby to effectively short circuit the two lamp pins'through one of said pins.' Although the invention is not to be so limited, in the preferred forms thereof herein illustrated and described, the short circuiting pin is directed upon insertion thereof into the lampholder into a space between said other lampholder blade and the contact portion of the short circuiting member, said space being less than the diameter of a lamp pin, and said blade and contact portion being so'mounted or constructed that they will be resiliently urged apart by the insertion of the lamp pin therebetween, whereby to insure good electrical contact,

Referring now to the drawings, and more particularly to Figs. 1 through 5, the novel short circuiting means is shown there embodied in push- ,Wards and away from the ends of a fluorescent lamp and by the presence of a mechanism for resiliently urging the lampholders into coupling engagement with the projecting lamp pins I2, M. Said lampholders support a conventional instantstarting fluorescent lamp l6 and are carried by a base I8 which also houses the usual ballast and Wiring (not shown) associated with a lamp of this nature.

contact means 28 to eifect a detachable electric connection between said pins and a source of electric power.

Said last named means includes a pair of electrically conductive strips 3!), 32 of resilient material, for example, Phosphor bronzepwhich are received in shallow depressions 34 running longitudinally of the body 20 at the back thereof. These strips are suitably anchored in the; body and provided with binding: posts-34iwhich.

are adapted to function as terminals" for connecting power leads to the lampholderc The strip 3t! carries a pair lot-'opposediconcave:

wiping contact bladesdfi, 38; the same-beingicona nected to said strip by spaced oppositelywtwistemfingers Gil which permit said blades to be resiliently forced apart upon the entry ofLrala'mpw pin 52 therebetween. The other strip 32, for a reasonfsoon; to be. apparent, hfirSa-Ql y a single concave wiping contact-blade 5422i connccted; to saidstrip by, a twisted finger l l which allowsthe blade; 42; to be resiliently1moved;toWards@ the blades 35, St; Said; blade: 45-25;. is .so -disposedzas to. lie .in the path, ofqtravel ,of.--the.@lamp; pi l4 upon insertion of therlamp. in,the;;lampholder [0 whereby. it will slidinglyenga e the; external cylindrical pinsurface.

The lamppins 1-2, is areguidedginto; apertures dimegistered with the .blades -36, "38-;'-42 by in clined' grooves 38:: on the .facerofa the .lampholder;

The lamp. E5 is inserted in the; lampholders- [0 by aligning. its pins. withthe grooves. wand-then: pushing the lamptoward the base Iii. Thisiorces th lampholders to rock outwardly until thefiins :2, M. are in line..withithelapertures- 4.:6;.;-;whe.r.e;- upon the lampholders, undeninfiuence:.oisprings rock back into couplingeengagementxwithitho lamp; thrusting said; pins into. the; apertures; -145- and into wiping engagementzwiththe: blades .36;

Pursuant; to the invention,: a; novelv'shortz. ci-rtzcuiting..means is embodied incach-fof ;the ;lamp=- holders iii. Said means. includesan; electrically conductive member 53; electrically. connected: to the strip iiileand havinga contact portionspaced from the. contact blade and .yethde'signed ezto slidingly engage the lamppim I4." Saidmember 511.: may, like the strips sdgt-t-comprisea strip ofelectrically conductive resilientamaterial e. E2, Phosphor bronze,v and i can be fabricated convene iently as part of the strip Btu-in themanner illustrated in the embodiment-eithe-.inventionnow being described, although it :willv be. appreciated that this member alternatively. may be connectedphysically and electrically ltojthestrip in other ways, for example, by; welding-.or. riveting, .or even be wholly separate fromthe: strip 3llcphysically and connected electrically.thereto'by. alead wire. However, in the form ofathe. invention under consideration, .it is convenientitohavet the member 59 integral with; the, strip... 30;and; more particularly, integrally connected -to-rthe free end, of; the contact blade 36; .Said;member;.50,.;ex-. tendszin the general direction of the contact blade 42 andterminates in a contactportioni52which, as; illustrated, may have a c nvex surf 3% e: signed to .slidingly engage. the 1 pin; L4. The. con,-

tact portion is spaced away from the blade fla slightly less than the diameter of the lamp pin l4 so as to lie on the .opposite side of the pin l4 when the lamp is inserted in the lampholder. Although the contact portion 52 is shown as in opposition to the blade 42 (Fig. 4) to save space, it will be understood that in accordance with the invention, it is only necessary for it to be so disposed that it will contact the pin 14 after insertion of the lamp Without contacting the blade 42.

Because of the inherent resiliency of the member 56, the contact portion 52 will press against therpin; 4; when-said pin: is inserted-between the contact blade 42 and said, contact portion. It

may be desirable, however, due to the rather long span between the contact portion 52 and .theendof .themember 50 integrally connected to the contact blade 36, to anchor said member 5esnearthercontactrportion 52. For this purpose, I may fiXJaI segment of the portion 50 near the contact portion- 52between two bosses 54 on the lamplbodyizil. This causes the contact end of the member 5flbeyond said bosses to act as if provided with a cantilever support at the bosses, and thus increases the resilient effort tending to maintain the contact. portion 52;.inengagement with thepinli h a g r V In- 0113612410 accommodate; the member. 50 ,the body:20 ishollowed outz fi s-indicated at. 5& .The reaiv of the-lampholden coveredubythe-usual back platet58 held in place by a;s.crewn 60%,. i It i will: be seen. that theeshortl circuiting .,cur-. rent passes from the strip 3,0;th ntn-lgh,the-.-con. tact;.blade. --36, -member; '50, ;contact. portion .52, pin; M, and contact blade'fl to thestrip 3.2 PI'hus, the shorting; current only passes through-one lamp pin. This appreciably reduces the number and complexity. of; parts required,- for shorti cirrcuiti iin, comparison;withz other-shortcircuiting. lamDhQlders.

In Figs. 6 through 10, the noyelishortcircu-ita ing-meansis shown-embodiedin: twist typetlampholders BOF such, forrexampla aszthose shownin United; StatesLettersBatent No.. 2,282,28l ,=issued May 5, 194:2,v V Said;lampholders;areamounted; on,

a standard base 62 and supporttaminstant starting fluorescent lamp;- 64;. i. Each lampholderr-includesra body A Minor; insulating material which is mada, fast.=in; conventional;.manner :to the base. hee rear. of. the. body; .is suitably; I grooved .to me.- ceive a pair of electrically," conduotiuei strips :58, Ill: which terminate in contactiportionsrror blades. '12,:'ld respectivelm The blade 12 is bowed andiproieots fronrthe, rear to: adjacent itheifront; or. the-=body Where; it is disposed in.- a side-wall. of: an i arcuate-slot; J5 Said slot is concentric with the base of a Straight slot flit, also, providedrthe front .of; the body 66, Theother blade 3!;4 extender-rem. the .-rear, .t o adjacent, the; frontsofithe .body where. it is-rdist-r posed near-the baseiot said ..-straight-.-slot. The blades 12,- Sid-rare spaced apart .av distance -greater than that between the lamp pins 80, 82 sort-hat" they. may be forced .togetherrbyasaid ,pins swherebytto causetsaidiblades tot pressiagainst the pinswhen thelamp, is in positions One or both of the blades is arranged tosbe resilientlybiassed to ridlesposltiongwhen deflected toward the; ,centertof the circular land- .8 0}? formed by the-slotfilt: To;thissendsthe-contact forming portion rat-the tip; of the blades! 2 com-prises 11a: transversely extending IibbQHItiYi/ghQSBmBTlQS82k (Ri s. .9); areturned down intoapertures- 84- t the; reariofl thei'lampliolder body;- thBeflBl'liI'filgQOlw tion of said ribbon spanning;aldepressioniafi toe:

wardswhose bottom the contact can be freely urged when the lamp is inserted in the lampholder. The other contact 14 is disposed in a recess 88 opening at the rear of the lampholder. Said contact is backed up by a leaf spring 90 spanning said recess and having its ends received in grooves The lamp B4 is inserted in the lampholder 60 by disposing the pins 82 at eachend of the lamp adjacent the bases of the straight slots 18 and then twisting the lamp so as to cause the other pins 80 to ride in the arcuate grooves until the pins 80 reach the blades 1'2. As said pins travel through the slots 16, the pins 82 will depress the contacts 14 against the action of the springs 90. When the blades 12 are initially reached, they will be depressed toward the bottom of the recesses 86, relieving some of the pres sure on the springs 90. The centers of the blades 12 are indented, as at 94, to lock the lamp against inadvertent displacement with the pins 80 in desired position. When the pins 80 reach the centrally disposed indentations 94, more pressure is released from the springs 90 which, however, are still sufficiently strained to maintain an efiicient contact pressure of the

blades

12, 14 on the

pins

80, 82, respectively.

The short circuiting means embodying the invention in the twist type lampholder just described comprises a resilient electrically conductive strip of sheet material 96 electrically connected to the strip 10 and having a bowed contact portion 98 spaced from the contact blade 12 and yet designed to slidingly engage the lamp pin 80, preferably at a point diametrically opposite to the point engaged by the blade 12. Said contact portion 98 lies in the arcuate groove I6, being disposed in the side wall thereof opposite to that to which the contact blade 12 is provided. The free end of the contact portion rests upon the side wall of said groove. Said short circuiting member 96 has an offset portion I00 integral with the contact portion 98 and extending rearwardly therefrom through a hole H12 in the lampholder body 65. This offset portion is connected at the rear of the body to a shank I04 whose free end I06 is disposed beneath the conductive strip 10. Said shank and conductive strip may be welded together or may be merely pressed together between the body 66 and the back cover plate 108, the latter being held in position by a screw H0.

To facilitate holding the short circuiting member 96 in place, I may also employ an insulating panel H2 which overlies the shank I04 of said short circuiting member and is sandwiched between this shank and the other electrically conductive strip 68 (see Fig. 8).

The space between the contact portion 98 and the blade 12 at the indentation 94 is slightly less than the diameter of the lamp pin 8| however,

by bowing said blade and contact portion and supporting both their ends, sufficient resiliency is imparted to ensure good electrical contact.

It will be understood that, as in the first embodiment of the invention, short circuiting current passes from one terminal of the source of power supply through the blade T2, lamp pin 80, and short circuiting member 96, to the blade I4 and the other terminal of the source of power supply.

It will thus be seen that there are provided lampholders which achieve the several objects of the invention, and which are well adapted to meet the conditions of practical use.

As various possible embodiments" might be mad of the above invention, and as various changes mightv be made in the embodiments above set forth, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

Having thus described the invention, I claim as new and desire to secure by Letters Patent:

1. A lampholder of the character described for an electric lamp having a pair of projecting pins on each end thereof, said lampholder including a pair of blades, means to support said blades in spaced insulated relationship, and means to short circuit said blades when a lamp is inserted in said lampholder, said short circuiting means including an electrically conductive short circuiting member electrically connected to one of said blades and extending across toward but not into contact with the other of said blades, said member having a contact portion near said other blade and spaced therefrom transversely of the direction of travel of a lamp pin of a lamp being inserted into the lampholder, whereby said lamp pin upon insertion will b disposed between and engage both said other blade and said contact portion.

2. A lampholder of the character described for an electric lamp having a pair of projecting pins on each end thereof, said lampholder including a pair of blades, means to support said blades in spaced insulated relationship, and means to short circuit said blades when a lamp is inserted in said lampholder, saidshort circuiting means including an electrically conductive strip having one end integrally connected to one of said blades and the other end formed into a contact portion which is near yet spaced from the other blade transversely of the direction of travelof a lamp pin of a lamp being inserted into the lampholder, whereby said lamp pin upon insertion will be disposed between and engage both said other blade and said contact portion.

3. A lampholder of the character described for an electric lamp having a pair of projecting pins on each end thereof, said lampholder including a pair of blades, means to support said blades in spaced insulated relationship, and means to short circuit said blades when a lamp is inserted in said lampholder, said short circuiting means including a resilient electrically conductive strip integrally connected at one end to one of said contact blades and extending toward the other of said contact blades, the free end of said strip com-'- prising a contact portion which is spaced from the other blade transversely of the direction of travel of the pin of a lamp during insertion into the lampholder, whereby said lamp pin upon insertion will be disposed between and engage both said other blade and said contact portion, said strip being supported by the lampholder near said other blade to provide a point from which said contact portion may resiliently flex so as to be biassed against the lamp pin.

4. In combination with an electric lamp having a pair of projecting pins at each end thereof, a lampholder having at least one groove in the face thereof through which one of the lamp pins is adapted to travel during insertion of a lamp into the lampholder, said lampholder including a pair of blades, means to support said blades in spaced insulated relationship with at least one of said blades disposed at a side of said groove, and means to short circuit said blades when .a lamp is ingames:

7 madame-5 am Jamphbider; said: short eircuiting meanslincmdmg a short circuiting memberelea tnicallyz'connectedwo the cthemof said blades and havingxa .cunbact :porti'en lying in said gnome -opposed; to said-one blade spaced theref-rbm a distance less ihanthe diameter of said @1115; e

5. A combination as set forth inn laim i wherein theegroove in Lthe lampholden is;- arcuate.

6. vA110mmnationas set forth in clad-m4 wherein the Jampholder is provided with means-1150: lock the: .1a,mp against: inadventerrt displacement in a position: in which a am pin is "disposed between 1 Number the: lone b'l'azd'e sanrbrbheicontact portion :of the Name Date 2,295,757 Russell Sept; 15',-1942 2,313,036- Bu1't MM. 9, 1 948.