Fluorescent Fixture

Abstract

A longitudinally extending, partially translucent casing for a fluorescent tube contains a shade rotatable about the fluorescent tube controlled by a member exterior to the casing.

Description

This invention relates to a fixture for supporting a fluorescent tube and for controlling the direction of illumination therefrom.

Heretofore, fluorescent tube fixtures have substantially consisted of means for supporting the tube, ballast, cord and switch with little attention being paid to shading and adjustment of the illumination direction.

This invention provides a novel mechanical arrangement for controlling the radiation direction of light from a fluorescent lamp.

In a preferred embodiment, is shown a convenient and improved clamping means for attaching a fluorescent fixture or other device.

In drawings which illustrate a preferred embodiment of the invention:

FIG. 1 shows a perspective view, partially broken away, of the inventive fixture;

FIG. 2 shows an exploded view of the fixture;

FIG. 3 shows a vertical cross-section of the fixture; and

FIG. 4 shows in detail the clamping means for the fixture;

FIG. 5 shows a cross-section along the lines 5--5 of FIG. 2.

In the drawings; a standard 10, which may be clamped on to a table or shelf or the like is connected to support a casing 12 comprising an extended light-transmitting cylindrical plastic tube 14 extending in one direction from the standard and a shorter metallic tube 16 extending in the other direction from the standard. The plastic tube 14, the metal tube 16 and the standard are connected together to form a unit, with the tube open at both ends and defining a passageway therethrough.

Although the clamping means forms the subject matter of some discussion hereafter, it should also be noted that in the broader aspects of the invention dealing with the radiation shade adjustment, the clamped base shown may be replaced by a stand or by a support of another kind.

The light transmitting extent 14 of the casing corresponds approximately to the extent of the illuminated portion of the fluorescent tube to be mounted therein, although, as shown, the plastic tube will extend slightly farther on each end thereof.

The fluorescent tube ballast 18 is mounted in the metal tube 16, preferably by providing a cylindrical sleeve 20 projecting from the lamp adjacent end of the ballast, dimensioned to make a sliding fit within the plastic tube 14 which in turn, overlaps with a loose sliding fit, the tube 16. In the preferred embodiment, the metal tube 16, the standard 10, the ballast sleeve and the plastic tube 14 are firmly fixed in position by: threading the end of the standard, providing an aperture 22 in the tube 16, an aligned aperture in the tube 14 for passage of the threaded end therethrough, and providing a threaded bore 24 in the sleeve 20 designed to receive the threaded shank end. The shank is slid through bore 22 and the bore in tube 14 and threaded into the sleeve 20 and tightened to clamp the tubes 14 and 16 between a shoulder 26 on the shank and the sleeve 20. With this arrangement, the casing is securely attached to the shank. The ballast 18 is coupled with a switch and operating stem 28 mounted in the casing and dimensioned to project out of the end of the tube portion 16 when the ballast is fixed in position. An end cap 30 preferably of plastic is threaded into the end of the metal tube, to form a closure therefor of good appearance, and the main cap wall is centrally apertured to provide passage of the switch spindle 28.

Adjacent and/or about the ballast, the metal tube 16 is provided with internal counter weighting, not shown, if necessary to balance the projecting weight in the other direction, of the fluorescent tube and casing.

The free end of plastic tube 14 is also provided with an end cap 32 slidably rotatable (not threaded) in the end of the tube 14 and carrying, as described hereafter, means for supporting the fluorescent tube and socket in the casing.

The ballast mounting sleeve 20 is provided with a central spindle 34 coaxial with tubes 14 and 16 extending toward the bulb location. The spindle tapers toward the outer end, and just inwardly of the taper is provided with a narrowed area 35 to provide a shoulder 36 facing the direction of the ballast. In addition the spindle is diametrically slotted at slot 38 to a depth inward of shoulder 36.

On this spindle 34 may be snapped the support disc 40, having an aperture 42 to slide over the tapered spindle 34 and to be held in place by the spindle shoulder 36 when the disc has passed.

As shown, one of the fluorescent lamp sockets 43 is bolted to the disc 40 on the side of the disc 40 remote from the ballast, substantially centrally of the circular edge of the disc 40. The socket 43 is recessed sufficiently to receive the tapered end of spindle 34 when the disc 40 is received on the spindle. The circular edge of disc 40 is provided with a cut-out 45, as shown, to allow passage of the fluorescent tube wires, and is provided with spaced (here 3) outwardly projecting tabs 44 for support of the shading shield as hereinafter discussed.

The plastic end cap 32 is provided with a central aperture as hereinbefore discussed.

A disc 46 of circular outline is designed similarly to circular disc 42, and is provided with a similar number of tabs 44, here three, which are designed to reside in corresponding slots in the shading member. The second socket 47 for the fluorescent lamp is fastened by bolts to the disc 46. The socket 47 is threaded to receive the bolt 51 so that when the bolt 50, with its head resting on the end cap and passing through the central bores in the end cap and in disc 46, is designed to thread into the socket 47 to a depth to space the socket from its counterpart the correct distance to house the tube. The end cap 32 with its inwardly extending side walls, is provided with an arcuate lining 52 which is dimensioned to rest on that part of the edge of disc 40 which is without tabs, the lining providing a shoulder at each end to meet the side edge of the first tab 44 encountered in each arcuate direction. The effect of the interference between the side edges of the outer tabs 44 and the ends of lining 52, is that the disc 46 is keyed to the end cap 32 for rotation therewith and for adjustment thereby.

An opaque shade 50 for the fluorescent tube is provided, being a portion of a cylinder, convex inward and concentric with the tube, encompassing preferably, about 160.degree. of the 360.degree. radiation direction from the tube. The opaque shade is preferably of aluminum and designed to structurally connect the two discs 40 and 46 for rotation together. In the preferred embodiment, the structural connection is achieved by making the shade 50 of resilient material and of a shape, more convex than the complement of the tab locations and slotted at slots 48 to receive the tabs 44 from both discs. Thus the shade 50 is applied to the tabs 44 being designed to be resiliently flexed slightly wider when the tabs 44 are received in the slots, and the shade 50 inwardly biased against both disc surfaces is firmly held in position and couples the discs 40 and 46 for rotational motion together.

The wires for plugging in the lamp and for connecting the ballast and tube are shown only schematically as their arrangement and connection will be well known to those skilled in the art.

With the lamp assembled and connected, as described, the shade 50 may be adjusted by turning the end cap 32 to direct the rays from the fluorescent through a wide angle of directions. A tooth 54 on spindle 34 just inwardly of disc 40 cooperates with a tooth 56 on the disc to limit the rotation to about 350.degree.. When the end cap 32 is rotated, the two discs 40 and 46, coupled by the shade 50 are rotated, and with them both light sockets 43 and 48 and the tube. A convenient and straghtforward method of providing controlled illumination and shading in various directions is provided controlled by adjustment of the end cap 32. The shade may be provided with a reflectant coating to the degree of reflectivity desired.

It is within the scope of the invention to provide a shade 50 adjustable by the end cap 32 either: coupled to both end socket supports in a different manner from that shown, or a shade 50 supported at both ends for rotation by the end cap 32 in a manner allowing rotation of shade 50 by end cap 32, without rotation of the socket.

With the specific form of invention shown, a fluorescent bulb is replaced by removing bolt 51, then end cap 32, detaching disc 46 from shade 50 by flexing the latter outwardly, and withdrawing the end cap 46 and socket 47 from the fluorescent tube. The tube is then withdrawn and a new tube fitted in the remote socket 43. The socket 47 and disc 46 are then fitted over the near prongs of the new tube, the shade is fitted over the tabs of disc 46 and the end cap screwed back into place.

In a preferred form of the invention there is provided a novel clamp, suitable for the mounting of fixtures of the type disclosed. The clamp avoids the disadvantages of prior clamps which create their clamping pressure exterior to the common mounting of the clamping ears and along the cantilever extent thereof. Such prior constructions have created oblique biasing pressures and unsure clamping.

Accordingly there is here provided a clamp for fluorescent lamps or the like, which is clamped along the common mount for the clamping ears, and thus provides direct and sure clamping pressure.

The clamp comprises a first clamping ear 60 with a stepped clamping extremity as shown, with a bore 52 to render it adjustably slidable on the standard 10 whereon it may be fixed by adjustment of the set screw 64. A cooperating clamping ear 66 is provided with an aperture 68 to be slidable on the shank with a stepped extremity facing the extremity of ear 66 so that the two clamping ears will cooperate to attach to a shelf or table edge, as shown. A nut 70 is threaded on an extent of the shank on the side of the cooperating clamping ear remote from the first clamping ear, and designed to be rotated to limit the maximum spacing of the ears 60 and 66 whereby nut 70 may be tightened to clamp the ears about the support.

Claims

1. Fluorescent fixture comprising:

a longitudinally extending casing;

light transmitting portions in the side of said casing;

means for rotatably mounting toward one end of said casing, one end socket for a fluorescent bulb,

means for rotatably mounting, toward the other end of said casing, the other end socket for such fluorescent bulb,

an opaque member designed to connect said rotatable mounting means and to rotate therewith whereby said opaque member couples said mounting means for rotation together,

said opaque member being designed and constructed to rotate outside the locus of a fluorescent tube mounted in said socket and designed and constructed to occlude by rotation, varying areas of said light transmitting portions,

2. A fluorescent fixture comprising:

a longitudinally extending casing, light transmitting portions in the side of said casing,

a socket for each end of the tube,

means for mounting each said socket,

a shade member connectible to each of said mounting members, dimensioned so that, when connected, said sockets are spaced the length of a fluorescent tube to receive the prongs of a fluorescent tube, said shade member being located to allow the presence of said tube, but to occlude the path of radiation therefrom in predetermined directions, while allowing radiation in other predetermined directions,

whereby said mounting members and said shade form an assembly,

means for rotatably mounting said assembly in said casing,

means for rotating said assembly when so mounted.