US 3631376 A
Description (OCR text may contain errors)
United States Patent Inventor Thomas C. Haliaker St. Louis County, Mo.
App]. No. 88,598
Filed Nov. 12, 1970 Patented Dec. 28, 1971 Assignee Emerson Electric Co.
St. Louis, Mo.
FLUORESCENT LAMP HOLDER MOUNTING 5 Claims, 4 Drawing Figs.
11.5. C1 339/53, 240/51.1l R, 248/27, 339/119 L Int. Cl Holr 33/08 Field of Search 339/50-57,
119 R, 119 L,120,121,125-127, 131,136,176 R, 220 C, 220 R; 248/27; 240/5l.1 1, 51.12, 78
 References Cited UNITED STATES PATENTS 1,806,575 5/1931 Ciraolo et a1. 339/50 X 2,249,471 7/1941 Harnm et a1. 339/147 C X 2,616,643 11/1952 339/120 3,328,577 6/1967 339/50 R X 3,568,132 2/1971 Johnson 339/50 R Primary ExaminerMarvin A. Champion Assistant ExaminerTerre11 P. Lewis Attorney-Polster and Polster ABSTRACT: A mounting plate for providing 1imited play in any direction for a fluorescent lampholder for a U-shaped lamp.
PATENTED 05828157] 6 3 pm} 4 THOMAS C. HALFAKEQ 44 My fl WA,
FLUORESCENT LAMP HOLDER MOUNTING BACKGROUND OF THE INVENTION This invention relates to a mounting plate for providing limited play in any direction for a lamp socket for a bent or U- shaped fluorescent tube. Such tubes have an almost unlimited number of small misalignments and therefore require mounting sockets which will tolerate such misalignments and still provide good electrical contact with the lamp end pins and good mechanical support. Several approaches have been attempted, but none has proven entirely satisfactory. For example, the sockets have been loose-riveted to a standard mounting plate or else have been mounted on nylon spacers and the spacers have been screwed to standard mounting plates. In the first approach, the sockets are permanently attached, the rivets provide a very poor reliability and uniformity of performance, and the sockets can not be moved easily to accommodate lamps of differing widths (standard widths are now 3% inches between ends and 6 inches between ends, with up to plus or minus la-inch tolerance in this dimension alone). In the second approach, the sockets tend to fall off during relamping.
One of the objects of this invention is to provide a mounting means for a U-shaped fluoresc'ent tube which will overcome the deficiencies noted in the foregoing prior art devices.
Another object is to provide such a means which is easy to manufacture and to use.
Other objects will occur to those skilled in the art in the light of the following description and accompanying drawing.
SUMMARY OF THE INVENTION In accordance with this invention, generally stated, a fluorescent lampholder mounting is provided which comprises a plate having a socket wire aperture in it, a pair of fingers at one edge of the aperture for loosely trapping a screw boss in the lampholder, and a second aperture through which a fastener holds the lampholder loosely, the second aperture being substantially larger than the shank of the fastener. In the preferred embodiment the fastener is a shoulder screw having a shoulder which is somewhat thicker than the thickness of the mounting plate. Also in the preferred embodiment the second aperture is rectangular. Also in the preferred embodiment the mounting plate includes a turned flange having a slot in it adapted to accept a fastener to permit the mounting to be shifted laterally to accommodate lamps of different widths.
BRIEF DESCRIPTION OF THE DRAWINGS In the drawings, FIG. I is an exploded view in perspective of one illustrative embodiment of lampholder mounting of this invention, together with a lampholder to be supported by the mounting;
FIG. 2 is a view in rear elevation of the mounting and lampholder of FIG. 1;
FIG. 3 is a view in side elevation, partly cut away, of the mounting and lampholder of FIGS. 1-2; and
FIG. 4 is a bottom plan view of the mounting and lampholder of FIGS. 1-3.
DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings for one illustrative embodiment of mounting of this invention, reference numeral 1 indicates a lampholder being held to a mounting bracket 2 by a screw 3. The lampholder 1 may be of standard molded plastic construction and may include a hollow cupped casing 11 having lamp sockets 12 in its forward, closed, face, and a pair of wires 13 emerging from its rear, open, face. A screw boss 14 is provided in the upper edge of the casing 11 whereas the lower edge of the casing is broadened to encompass a threaded hole 15. A sheet plastic spacer I6 is riveted to the casing substantially within the cup of the casing.
The mounting bracket 2 is formed of sheet metal and includes a flat face 20 having an upper aperture 22 and a lower rectangular a rture 23. A pair of fingers 21 struck out at the upper edge 0 the upper aperture loosely trap the screw boss 14 when the rear face of the lampholder l is placed flush against the flat face 20. The screw 3 includes a shoulder 31 which has a diameter substantially less than the height of the rectangular lower aperture 23. By way of example, the lower aperture may be 0.250 inch high and 0.312 inch wide and the shoulder 31 may have a diameter of about 0.187 inch. The sheet metal may be l8-gauge steel and the shoulder may be about 0.055 inch thick.
The lampholder is mounted to the mounting bracket simply by slipping the wires 13 through the upper aperture 22 and tightening the screw 3 in the threaded hole 15. The screw and fingers allow the lampholder ample freedom to accommodate any misalignment within manufacturing tolerances but permit only very limited movement in any direction.
The mounting bracket 2 also includes a pair of lateral wings 24 and a lower flange 25. The lower flange 25 is provided with a slot 26 which is proportioned to accept a rivet, not shown, by which it is slidably mountable on a fixed structure, not shown. When thus mounted, the bracket may be moved easily from one lateral position to another by grasping the wings 24. If the slot 26 is made 2% inches long from the center of end curvature to the center of end curvature, only one of each pair of mounting brackets needs to be made slidable, and any problem of the bent tube slipping laterally with the lampholders is obviated. 7
It will be seen that I have provided a simple, secure and effective mounting means for fluorescent lampholders which must be given many degrees of freedom. Numerous variations in the mounting means, within the scope of the appended claims will occur to those skilled in the art in the light of the foregoing description.
Having thus described the invention, what is claimed and desired to be secured by Letters Patent is:
l. A fluorescent lampholder mounting comprising a plate having a socket wire aperture and a second aperture below the socket wire aperture, a pair of fingers at an upper edge of the socket wire aperture, said pair of fingers being proportioned and spaced apart to trap loosely a screw boss in a lampholder, and a fastener extending through the second aperture, said fastener having a shank part substantially smaller than the second aperture, said fastener being adapted to hold the lampholder loosely to the plate.
2. The mounting of claim 1 wherein the fastener is a shoulder screw having a shoulder which is thicker than the thickness of said plate.
3. The mounting of claim 2 wherein the second aperture is rectangular, the height of said second aperture being less than its width.
4. The mounting of claim 1 including a turned flange on a horizontal margin of the plate and a slot in said flange adapted to receive a fastener for mounting the plate slidably on a fixed structure to accommodate lamps of different widths.
S. The mounting of claim 4 wherein the length of the slot is between about 2% and 3 inches.