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Publication numberUS1813492 A
Publication typeGrant
Publication dateJul 7, 1931
Filing dateOct 19, 1929
Priority dateOct 19, 1929
Publication numberUS 1813492 A, US 1813492A, US-A-1813492, US1813492 A, US1813492A
InventorsGoodloe Alfred Minor
Original AssigneeExchange Lumber Company
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Translucent panel for lamp shades and other purposes
US 1813492 A
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Description  (OCR text may contain errors)


This invention relates to the production of translucent wooden panelssuitable specially for use in lamp shades, but adapted also for other analogous uses; the object of 5 the invention being to produce from the wood of certain trees, and specially from abnormal growths on the trunks of trees, known in the wood working industries as hurls andswirls, panels of such thinness as to be effectively translucent, and so treated as to maintain their shape under ordinary changes of humidity and temperature, and to he in all other respects adapted to serve practically the purposes of a lamp shade panel.

Sheets of wood cut from hurls and swirls are highly figured and variously tinted, and they present a great variety of ornamental pa terns, because of which burl plywood is greatly prized for veneering purposes. And

for such purposes it can be readily adapted since, when glued firmly to a solid hacking, its structural weaknesses and irregularities do not manifest themselves. it

But when it is attempted to use veneer .25 of the thickness used in some plywoods, es-

pecially hurl'veneers, for purposes such as lamp shade panels, where there is no solid backing for the thin sheet, problems and difficulties present themselves, whicharise 3 from the fragility of the material, and from other inherent characteristics, such as its unequal expansion and contraction with changes of humidity or oftemperature (this expansion and contraction being considerably greater in one direction, across the grain, than in the other), and its tendency to warp, swell, bulge, buckle, and otherwise lose its shape. These tendencies are the greatest in hurl veneers, for the reason that in hurl wood 40 the figures are very irregular and the fibers run in various directions, instead of being approximately parallel, as in normal growths of timber. On the other hand, burl veneers make the most desirable lamp shade panels in respect to the matter of ornamentation, be-

cause the beauty of the rich variety of at terns they present, and of their various tints and hues, is greatly enhanced when a strong light is placed behind them. For the effect of a strong light behind them is to bring to View patterns and colors that do not appear on the surface. 7

Therefore it is the main object of the present invention to produce thin sheets, such as are used in plywoods, and specially sheets of hurls, having characteristics such as make them suited mechanically, as well as artistically, for use as lamp shades; that is to say, sheets of the requisite thinness for effective translucence, yet having suficient 0 strength to be supported at their edges by an ordinary frame, and even to be united at adjacent edges by lacing, and which do not warp, bulge, buckle or otherwise lose their shape,under the usual variations of moisture (55; and temperature.

In the parlance of the wood working trades there is a recognized difference between hurls and swirls; but both are abnormal growths, and are substantially the 7o same in their characteristics for the purposes of this invention.- Hence it is tobe understood that the term fburls, as used herein, is intended to cover both.

Burls may occur in almost any species of trees; but cucumber, poplar, walnut, ash, cherry, maple and redwood hurls are among those that are best adapted for the purposes of the present invention.

In order to render the thin, single ply sheets of wood, especially hurls, physically suitable for use as lamp shade panels and for similar uses they are subjected to treatment which renders them moisture proof. Wood is very hygroscopic, and hence a thin sheet of 851 wood, not glued to a solid base, but supportedat its edges,,is liable to lose shape under the ordinary changes of humidity and temperature to which lamp shades are exposed. As already stated, in sheets of ordinary wood the expansion is practically all in one direction, namely, across the grain; but in the case of hurls, the fibers run irregularly and hence the expansion is in different directions and in different degrees.

In rendering the thin wooden sheets moisture proof for the purposesof this invention it is important that the treatment be such as not to impair, but rather to conserve and render permanent, the desired optical effects, 10c

It has been found by experiment that certain treatments of the wooden sheets which improve them in respect to increased translucence, are accompanied by detrimental effects of a physical sort, and hence cannot be successfully used for the purposes of this invention.

I have found, however, that moisture proof sheets of wood, especially burls, in all respects suitable for the purposes of this invention, may be obtained by the use of commercial veneer impregnating varnish, such as is obtainable on the market and is commonly used as a varnish for veneers.

The best results thus far secured have been obtained by the following procedure:

1. Thoroughly impregnate the sheet with commercial veneer varnish, applying the same by spraying, brushing or dippin 2. Then apply over the varnish a thin surface coating of shellac. V

3. Then apply clear lacquer, preferably two or three coats, over the shellac. This may be done by spraying or brushing.

The purpose of the coating of shellac is to serve as a' separator between the. varnish and the lacquer, as it is found that the desired results are not satisfactorily obtained if the lacquer is applied directly upon the varnish. Any other substance that will serve the same purpose may be substituted for shellac.

The foregoing treatment has no detrimental eifect upon the translucence of the panel, but rather increases it; and it conserves or renders relatively permanent the desirable optical effects. The main -effect of the varnish is to increase the transl'ucence of the sheet, though it also contributes to the moisture proofing thereof. The latter effect is obtained mainly by the coatings of lacquer.

hat is specially advantageous for the purposes of this invention, it is found that the moisture proofing treatment as described above strengthens the sheets to such a degree as to make practical the attaching of the panels together by lacing. For with panels so treated, even when made of burl wood, it is possible to punch clean holes near enough the edges of the panels for lacing them together, without danger of the rupture of the margin between the holes and the edge of the panels. T his is a matter of practical iniportance for the reason that the lacing method of attachmentis less expensive than the use of a. wooden frame.

Another advantage of the moisture proofing of the panels is that the glazed surface thus produced can be readily cleaned and polished, and that it does not catch dust, as when linseed or other oil is used for the purpose of counteracting the hygroscopic property of the wooden panel.

In the accompanying drawings, Fig. 1 is a side el vation of a lampshade formed of wooden panels, the adjacent edges of the panbe made of thin, single ply sheets of burl wood, rendered moisture proof by the process hereinbefore described,- or by any other process which will impart thereto the requisite physical properties without impairing the translucence thereof.

Adjacent edges of panels A are attached together by cords a laced in the usual way through holes punched in the panels in rows parallel with, and a short distance from, the edges, and the 1 top and bot-tom edges are bound with similar lacings a.

Lamp shades thus constructed of different varieties of burl wood have proved to be practical and commercial articles, which have met with great favor and give entire satisfaction to purchasers.

Fig. 2 illustrates a commercial type of lamp shade in which the moisture proofed panels A are supported by a frame formed of wood en side strips Z) for supporting the edges of the panels, top and bottom pieces 0, c, and obliquely disposed cross strips (Z which divide each panel into two parts. The object of this subdividing of the panels is to produce various ornamental effects by the use of different colors for the several parts of a panel. It is obvious that the panels may be thus sub=-divided iiio three or more parts.

hat is claimed is A lamp shade panel consisting of a singleply thin translucent sheet of burl wood strengthened v and rendered self-sustaining and shape-retaining under usual variations of moisture and temperature by impregnation and coating with suitable substance which does not impair translucence and with out other layer of wood or other material superimposed thereon. I

In testimony whereof I have signed this specification.


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2435759 *Nov 13, 1945Feb 10, 1948George SpawLamp shade
US6190024 *May 2, 1997Feb 20, 2001Dominic Anthony HackettLampshade and a method for making a lampshade
US6786621 *Dec 3, 2002Sep 7, 2004Mode Interiors LlcDo-it-yourself lampshade kit
US8021014Dec 8, 2006Sep 20, 2011Valinge Innovation AbFloor light
US8092036 *Jul 9, 2007Jan 10, 2012Valinge Innovation AbFloor light
WO2002018838A1Aug 31, 2001Mar 7, 2002Sviland ElenDo-it-yourself lampshade kit
U.S. Classification362/356, D26/136, 362/360
International ClassificationF21S6/00, F21V1/00, F21V13/10, F21V7/00
Cooperative ClassificationF21V1/00, F21V13/10, F21S6/005, F21S6/002
European ClassificationF21S6/00D, F21S6/00S, F21V1/00, F21V13/10