US3185837A

US3185837A - Electric light fittings

Info

Publication number: US3185837A
Application number: US207602A
Authority: US
Inventors: Stern Bernard
Original assignee: ROTAFFEX GREAT BRITAIN Ltd
Current assignee: ROTAFFEX (GREAT BRITAIN) Ltd; ROTAFFEX GREAT BRITAIN Ltd
Priority date: 1962-07-05
Filing date: 1962-07-05
Publication date: 1965-05-25
Anticipated expiration: 1982-05-25

Description

May 25, 1965 B. STERN 3,135,837

ELECTRIC LIGHT FITTINGS Filed July 5, 1962 2 Sheets-Sheet 1 (AH/En! ToR BERN ARD TE? N mm+ mo y 5, 1965 B. STERN 3,185,837

ELECTRIC LIGHT FITTINGS Filed July 5, 1962 2 Sheets-Sheet 2 iii 2? BERNARD STERN United States Patent 3,185,837 ELECTRIC LIGHT FITTINGS Bernard Stern, London, England, assignor to Rotafiex (Great Britain) Limited, London, England, a corporation of Great Britain Filed July 5, 1962, Ser. No. 267,602 Qiaims. (Cl. 240-52) This invention relates to electric light fittings and is designed to provide a new or improved arrangement for supporting an electric lamp and which is adjustable to suit various sizes and types of electric lamps. A further object is to provide supporting means for the adjustable lamp fitting whereby the latter can be turned to throw light from the lamp in various directions.

According to the invention, a support for an electric lamp holder is mounted within a tube adapted to enclose at least the stem of an electric lamp, the lamp holder support being adjustable along the length of the tube to accommodate lamps of different lengths. The tube may be mounted in a bracket so as to be capable of swinging about a diametrical axis of the tube, and if desired the bracket may be mounted on a supporting member and adapted for rotation about an axis at right angles to the said diametrical axis. Conveniently, the lamp holder may be carried by a diametrical web in a member slidably mounted in the tube, the tube having two axially disposed slots diametrically opposite one another for engagement by studs on the member carrying the lamp holder to guide the said member and limit its movement relatively to the tube.

One particular construction will now be described by way of example only, with reference to the accompanying drawings, in which:

FIGURE 1 is a perspective view of an electric lighting fitting constructed according to the invention,

FIGURE 2 is a sectional elevation of the fitting shown in FIGURE 1, and

FIGURE 3 is detail sectional elevation of part of the fitting.

Referring to the drawings, the particular electric lighting fitting illustrated is intended for use with a spotlarnp of the kind in which part of the glass envelope of the lamp is silvered so as to serve as a reflector. The fitting comprises a metal tube which has an end cap or disc 11 at one end, the said end cap or disc 11 having a central aperture 12 for the passage of flexible electric supply leads to the interior of the tube 16. The open end of the tube will be referred to as the front end and the end having the cap or disc 11 will be referred to as the rear end. A shorter tube 13 which is a sliding fit within the bore of the main tube It is disposed within the main tube and has an integral diametrical wall 14 a short distance from the end of the shorter tube 13 nearest to the rear end of the main tube 10.

A rod 15 passes diametrically through the shorter tube 13 rearwardly oi the said Wall 14, the ends of the rod extending through axially disposed slots 16 in the main tube 10. The end portions of the rod 15 are screwthreaded, but for convenience the rod 15 may be screwthreaded throughout its entire length. A nut 17 is screwed on each end of the rod 15, each nut having a cylindrical neck portion 18 adapted to pass through a hole 19 in one limb of a substantially U-shaped bracket 26, and a washer or like spacing member 21 is fitted over each neck portion 13 so as to lie between the inner surface of the corresponding limb of the bracket 20 and the outer surface of the main tube 10. When the nuts 17 are tightened, the end faces of their neck portions will engage with the main cylinder 10 adjacent to the slots 16 so as to clamp the shorter or inner tube 13 to the main tube 10, and at Cal the same time the limbs of the u shaped bracket 20 will be frictionally engaged between the Washers or spacing members 21 and the heads of the nuts 17.

The U-shaped bracket 2% in this particular construction comprises three sides of a rectangle whereby the central or base portion 22 is substantially parallel with the rod 15 passing through the tubes. The said central or base portion 22 of the bracket 20 may be adapted in any convenient manner for mounting the bracket on a support or for suspending the bracket according to requirements. In this particular construction the bracket 20 is adapted to be mounted on one end of a tubular conduit 23 through which electric supply leads extend. For this purpose, a stop collar 24 is adapted to be screwed on to the end of the conduit 23, the outer end face of the stop collar having a peripheral cylindrical flange 25 defining a circular recess, and a blind hole 26 being formed in the said outer end face. A saddle collar 27 is adapted to fit in the said recess so as to project therefrom and a pin 28 projecting from the inner face of the saddle collar 27 engages in the said blind hole 26 so as to prevent rotation of the saddle collar relatively to the stop collar. The saddle collar 27 has a diametrically disposed groove 29 in its outer face to accommodate the central portion of the base 22 of the bracket 20, and a tubular locking screw 30 having a knurled head is passed through a hole in the centre or" the bracket base 22, through the saddle collar 27 and into engagement with internal screw-threads in the bore of the stop collar 24.

The diametrical wall 14 of the inner or shorter tube 13 has a central hole 31 in which an electric lamp holder is to be mounted so that the lamp holder projects into the forward portion of the inner tube 13. A lamp holder socket is shown in dotted lines 32 in FIGURE 2. The electric supply leads 33, see FIGURE 1, from the conduit are extended to pass through the hole 12 in the rear end Wall 11 of the main tube 16 to the lamp holder mounted in the inner tube 13. The stem portion of an electric lamp 34 can be inserted through the front end of the main tube 10 and its cap engaged in the lamp holder. By loosening the nuts 17 which clamp the inner and

outer tubes

10 and 13 and also engage with the arms of the bracket 29, the inner tube 13 can be moved axially within the main tube 10 until the outer end of the main tube Ill lies close to the rear of the electric lamp envelope or bulb as shown in FIGURE 1. The main tube It) can be turned about an axis of the rod 15 to direct light from the lamp as desired, and by tightening the nuts 17, the inner and main tubes will be clamped together and the main tube will be secured in the angular position to which it had been adjusted relatively to the bracket 20.

The main tube 10 serves as a neat housing for enclosing the lamp holder and the stem of the lamp, the adjustment of the inner tube and lamp holder with the main tube enabling electric lamps of different sizes and types to be accommodated.

I claim:

1. An electric lighting fitting comprising a main tube to enclose at least the stem portion of an electric lamp, an inner tube slidablewithin said main tube, a diametrical wall in said inner tube, said diametrical wall having an opening to receive an electric lamp holder, axially disposed slots in said main tube, radially outward projecting screwed studs on said inner tube, said studs extending slidably through said slots in said main tube, a U-shaped bracket embracing said main tube, said screwed studs extending through holes in the arms of said U-shaped bracket, and nuts on the outer ends of said screwed studs for locking the inner tube in an axially adjusted position along the main tube and locking the main tube in angularly adjusted position upon said U-shaped bracket.

2. An electric lamp mounting assembly comprising a main tube having opposed wall slots, a bracket having spaced arms one on each side of said main tube, said arms having apertures aligned with said slots, a lamp support member mounted for axial adjustment Within said main tube and comprising oppositely extending fixed projections extending slidably through said slots and rotatably into said bracket arm apertures, and fastener means on said projections adapted to be tightened to secure said support member in an axially adjusted positionalong said main tube and said main tube in a desired angular location on said bracket.

3. In the electric lamp mounting assembly defined in claim 2, said lamp support member comprising a support tube telescoped within the main tube and having a transverse wall in which is mounted a lamp socket, an electric conduit connection secured to said bracket, and flexible conductor leads extending between said conduit connection and said socket.

4. In the electric lamp mounting assembly defined in claim 2, said projections having threaded outer ends, spacers surrounding said projections between the bracket arms and said main tube, and said fastener means comprising nuts on said threaded projection ends having reduced sections extending through said apertures and said spacers into contact with said main tube whereby tightening of said nuts :draws said bracket arms and lamp support members toward each other with the main tube clamped therebetween.

5. In the electric lamp mounting assembly defined in claim 2, said bracket having a bridge connecting said arms, an electric conduit end connection extending through and clamped to said bridge, and flexible wires extending from saidconduit end connection to a lamp socket on said support member.

References (Iited by the Examiner ,7 UNKTED STATES PATENTS 1,493,487

NORTON ANSI-1BR, Primary Examiner.

LAWRENCE CHARLES, Examiner.

Claims

1. AN ELECTRIC LIGHTING FITTING COMPRISING A MAIN TUBE TO ENCLOSE AT LEAST THE STEM PORTION OF AN ELECTRIC LAMP, AN INNER TUBE SLIDABLE WITHIN SAID MAIN TUBE, A DIAMETRICAL WALL IN SAID INNER TUBE, SAID MAIN TUBE, A DIAMETRICAL OPENING TO RECEIVE AN ELECTRIC LAMP HOLDER, AXIALLY DISPOSED SLOTS IN SAID MAIN TUBE, RADIALLY OUTWARD PROJECTING SCREWED STUDS ON SAID INNER TUBE, SAID STUDS EXTENDING SLIDABLY THROUGH SAID SLOTS IN SAID MAIN TUBE, A U-SHAPED BRACKET EMBRACING SAID MAIN TUBE, SAID SCREWED STUDS EXTENDING THROUGH HOLES IN THE ARMS OF SAID U-SHAPED BRACKET, AND NUTS ON THE OUTER ENDS OF SAID SCREWED STUDS FOR LOCKING THE INNER TUBE IN AN AXIALLY ADJUSTED POSITION ALONG THE MAIN TUBE AND LOCKING THE MAIN TUBE IN ANGULARLY ADJUSTED POSITION UPON SAID U-SHAPED BRACKET.