US2138780A - Adjustable electric lamp - Google Patents

Description

Nov. 29, 1938.

Filcl Jan. 28, 1937 Patented Nov. 29, 1938 PATENT OFFICE 2,138,780 ADJUSTABLE ELECTRIC LAMP Clarence Birdseye, Gloucester,

Birdseye Electric Company, a

Delaware Mass, assigno'r to corporation of Application January 28, 1937, Serial No. 122,822

\ 10 Claims.

larly adjusted with respect to the socket-fitting portion of the base. A lamp of this constructlon may be screwed or otherwise fixed in an already-installed socket of any commercial constructlon and then adjusted angularly so that the light emitted thereby shall be direct or distributed most favorably for the requirements of the individual situation.

It is, of course, possible to install commercial sockets at any desired angle or to provide such sockets with external reflectors directing the field or beam oi light in any desired direction, Y

. but when such an installation has been made, it

is inflexible and the light distribution cannot easily be changed to accommodate diilerent requirements. For example, an installation may be made with the object of illuminating with the greatest intensity one end of. the space in a show window, whereas conditions'may change so that it becomes desirable to concentrate the light of the installation upon the center of the window space or along its rear wall or to create a spotlight efi'ect. Heretofore such a change could be effected only by repositioning the sockets or providing a new set of external reflectors. The present invention, however, provides an integral lamp structure adapted for any commercial socket and makes provision for the easy angular adjustment and readjustment oi the lamp with its reflecting surfaces to secure the desired distribution of its light. I

The mechanical construction of the flexible portion of the base of my invention may take various forms. Two of such constructions are disclosed in my U. S. Letters Patent No. 2,067,844, granted January 12, 1937. In one aspect the base herein disclosed consists in the further development of the invention of that patent with a view to embodying it in bases having articulated connectlons as distinguished from the ductile construction of the bases shown in my patent above identified. As will be hereinafter apparent the base shown includes a socket-fittingportion supplying the usual terminals for the lamp and interconnected intermediate elements insulatedfrom the socket-fitting portion and having capaciCl. 176-32) ity for universal adjustment so that the lamp may be readily inserted in the socket and then angularly adjusted as desired without exposing the lead wires or in any way impairing the insulating characteristics of the base or the integrity of its connections.

These and other features of the invention will be best understood and appreciated from the following description of a preferred embodiment thereof selected for purposes of illustration and shown in the accompanying drawing in which,

Fig. l is a view in elevation, with portions broken away, of an incandescent lamp equipped with a base of my invention,

Fig. 2 is enlarged sectional II-II of Fig. 3,

' Fig. 3 is a view in longitudinal section of the base and a portion of the bulb.

The bulb herein shown may be of any usual or commercial construction equipped with an in-- ternal reflecting surface or a separate reflector to concentrate and define the beam of light emitted by the filament, not shown, or other light source within the bulb. For example, the bulb it) may be provided as shown in Fig. l with an internal coating of metallic silver extending from the line of maximum bulb diameter to a line in the neck of the bulb and acting to hood the filament and direct the light ofthe lamp outwardly in a concentrated beam through the bowl of the bulb. The bulb includes the usual glass mount H which is sealed into its neck and which supports the filament structure. The upper end of the mount ll constitutes a solid press l2 in which are sealed the two ,lead wires I3 and M. An exhaust tube 9 of usual construction is shown as located within the mount Ii, this having been sealed at its lower end when the bulb was exhausted in the process of manufacturing the lamp.

The base shown in Figs. 1 and 3 comprises four'portions having distinct functions. First, the usual threaded, socket-fitting end portion 21,

view on the line second, an insulating disk member 25, third, a

sleeve portion 20 movably connected to the insulating member 24, and fourth, the sleeve portion I! which fits the glass neck of the bulb and is connected to the sleeve portion 20.

The sleeve portion I1 is cylindrical and of proper size to be cemented by cement i9 to the tapering end of the neck of the bulb. At its lower end it is flared to form an enlarged spherical portion l8 opening downwardly as seen in Figs. 1 and 3. The sleeve 20 is of substantially the same diameter and provided at its upper end with an enlarged spherical portion 2| which is concentric with the spherical portion i8 of the sleeve first mentioned andarranged to fit slidably therein. The two spherical portions are adjustably connected at diametrically opposite points by a pair of screws 22 and each is relatively adjustable with respect to the other about the axis of these screws. At its lower end the sleeve 20 is provided with spaced inturned hooks 23 shown in Fig. 2 as arranged substantially 90 apart. These hooks engage in a groove formed in the lower face of the insulating collar 25 which is of the proper exterior diameter to make a sliding fit within the sleeve 20. The collar 25 is also provided with a circumferential groove 25 which extends 180 and in which is movably received a stop pin 24 extendinginwardly from the inner wall of the sleeve 20. The collar 25 is thus securely connected to the sleeve 20 and may be rotated 180 with respect thereto.

The socket-fitting portion 21 of the base is substantially rigid in its-construction and may comprise sheet brass or the like molded or spun to present anexternal thread to be received in a socket. At its upper end it is provided with a series of hooked prongs which extend through the body of the collar 25 and are turned back into its inner surface. The threaded end portion 21 is thus rigidly connected to the collar 25 and turns with it with respect to the sleeve 20. The lead wire i3 is brought down through an insulating washer 28 which encircles the end of the exhaust tube 9 and is connected to the end terminal I5 of the socket fitting portion 27. The lead I3 is insulated below the washer 28 by a tube of asbestos or the like and is of sufilcient length to permit adjustment of the portions of the base without danger of breakage. The other lead wire I4 is similarly brought down through the washer 28 and connected to one of the prongs 30 so that the body of the socket-fitting portion 20 constitutes the other terminal of the lamp as usual. The lead wire H also is insulated in passing through the base and of suflicient length to permit adjustment of the bulb without danger of breakage.

As shown in Figs. 1 and 3 the end terminal l5 includes a spring leaf or extension arranged to make electrical connection with the center terminal of the socket before the lamp is screwed into the limit of its movement. It thus allows for approximately 270 rotation of the lamp about its longitudinal axis withoutbreaking the electrical connection thereto. This provision for rotary adjustment, in addition to that provided by the groove 26, makes possible a full 360 rotary adjustment of the lamp.

As the lamp is usually constructed and distributed for use the base is symmetrically and concentrically disposed with reference to the axis of the bulb as shown in Fig. 1, and the lamp may thus be screwed into the socket without special attention and consideration of any kind.

Having once fixed the lamp in its socket, any desired angular adjustment may now be secured by merely bending or tipping the bulb in the desired direction. Under these circumstances the spherical portion i8 is free to rock about the axis of the screws 22 and those portions of the base above the insulating disk 25 are free to rotate through an angle of 180 thus supplying the other component of movement required to ive the bulb capacity for full universal adjustment with respect to the socket-fitting portion of its base.

Having thus disclosed my invention and described a preferred embodiment thereof for purposes of illustration and not in any way in a limiting sense, I claim as new anddesire to secure by Letters Patent:-

1. An electric lamp comprising a bulb having a light source, sealed lead wires and a light reflecting surface, and an adjustable base including a socket-fitting end portion, a bulb-fitting sleeve, and intermediate portions having articulate interconnections giving the bulb capacity for universal angular adjustment with respect to said socket-fitting portion, the lead wires being enclosed in said sleeve and permanently connected to different parts of said socket-fitting portion.

2. An electric lamp comprising a bulb having a light source, sealed lead wires and an internal reflecting surface, and an adjustable base including a'socket-fltting end portion, and intermediate portions having a hinged connection between each other and a rotatable connection of limited range with said socket-fitting portion, the lead wires being enclosed in said intermediate portions and permanently connected to different parts of said socket-fitting end portion. 7

A'n electric lamp comprising a bulb having a light source and a light directing means, together with a metallic base including a threaded end portion, pivotally connected sleeves, an insulating member connected to one of said sleeves and having a rotary connection with said end portion and lead wires sealed into the bulb and permanently connected to the threaded end portion of the base.

4. An electric lamp comprising-a bulb having a light source, lead wires sealed into the bulb and light directing means, together with an adjustable metallic base including a socket-fitting portion, an annular insulating member secured to the said socket-fitting portion and having an opening therein for one of said lead wires, a sleeve rotatably connected to said member and having a globular extension, and a bulb-fitting sleeve having a globular extension enclosing the lead wires and arranged concentrically with that of the sleeve first mentioned.

5. An-electric lamp comprising a bulb having a light source therein and an internal metallic light reflecting surface, together with an adjustable base including a socket-fitting end portion and interposed sleeves having concentrically arranged globular portions arranged to turn one within the other for adjustment about a transverse axis, a rotary connection of limited range between said bulb and end portion giving the bulb capacity to turn on its own axis while the socketfitting portion remains at rest, and insulated lead wires enclosed by said sleeves and permanently connected to the socket-fitting portion of the base.

6. An electric lamp having a bulb containing a light source, and a metallic base. including a socket-fitting portionhaving an insulating disk secured to its inner end, a sleeve connected to said disk for hunted rotary movement and having an enlarged spherical portion, a second sleeve directly secured to the bulb and having also an enlarged spherical portion which is adjustably connected to the corresponding portion of the sleeve first mentioned, and insulated lead wires enclosed by said sleeves and permanently connected to the socket-fitting portion of the base. 75

7. .An electric lamp having a bulb containing a light source, and a metallic base including a socket fitting portion, a sleeve connected thereto through an insulating medium and having an enlarged rounded portion, a second sleeve directly secured to the bulb and having a correspondingly enlarged and round portion, means for connecting said rounded portions for relative adjusting movement, and insulated lead wires enclosed by said sleeves and permanently connected to the socket-fitting portion of the base.

8. In an electric lamp having a filament and sealed lead wires, a base comprising a pair of oppositely directed sleeves having concentric globular portions pivotally connected for relatively angular movement, and a socket-fitting end portion having an insulating ring connected to one of said sleeves for limited rotary movement, the lead wires being enclosed by said sleeves and permanently connected to difierent'parts of the end portion of the base.

sealed lead wires, a base comprising a pair of oppositely directed sleeves having a pivotal connection for relatively angular movement about a predetermined axis, one sleeve having a bulbfltting end, and a socket-fitting member having connection with the other sleeve for limited rotary movement about the axis of the bulb, the

lead wires being enclosed by said sleeves and permanently connected to diflerent parts of the socket-fitting member.

10. In an electric lamp having a filament and sealed lead wires, a base comprising a bulb-fitting sleeve having an enlargement, an intermediate sleeve having an enlargement connected thereto for movement. about a predetermined axis, the two sleeves forming together a closed chamber for enclosing and protecting the lead wires of the lamp, and a socket-fitting portion adjustably connected to one of said sleeves and having lead wires permanently connected thereto.

' CLARENCE BIRDSEYE.

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