US 2829081 A
Description (OCR text may contain errors)
E. C. SWEEM April 1, 1958 FOLDABLE DRAPERIES AND METHODS OF MANUFACTURE Filed Aug. 2, 1954 Fig.l
INVENTOR E.C. Sweem- 7 TTOBN E Y6 Unite FOLDABLE DRAPERES AND METHODS OF MANUFACTURE This invention relates to improvements in folding draperies, blinds, doors, partitions and the like, and their method of manufacture, and it has reference more particularly to such articles that are comprised of very thin strips or slats of selected wood or woods, joined edge to edge by flexible means that permits the strips or slats to be folded together or opened apart for the purpose of contracting or extending the article in width or length.
More specifically stated, the present invention relates to the making of pliable folding draperies, blinds, doors, partitions, screens and the like, from thin strips of decorative wood that are overlaid with and hingedly joined edge to edge by transparent, plastic sheets that seal and protect the wood; enhance its decorative effects; and add thereto the required strength and give the hinging action necessary for folding the strips flatly together and the extending of the article to full width or length when such is desired.
It is the principal object of this invention to provide pliable, flexible, extendable and collapsible articles of those kinds previously named, made of thin strips or slats of decorative wood veneer such as walnut, oak, birch, redwood, mahogany and various others; these strips of wood, as assembled to form the designated article, being overlaid on both sides and joined edge to edge with thin, transparent sheets of plastic that are bonded thereto under the action of heat and pressure, thus to strengthen, protect and preserve the wood without impairing flexibility, and to provide the hinge-like joints between strips that permit them to be folded flatly together, and opened apart.
It is also an object of the invention to provide a method of manufacturing articles of this character that is practical and economical; whereby the natural decorative characteristics or features of the selected woods are preserved and enhanced; that insures long life to the article and provides the desired and necessary hinge connection between adjacent strips that makes possible the folding and unfolding action.
Yet another object of the invention is to provide a method of manufacture that permits use, in articles of this character, of exceptionally thin strips of wood without any danger of their checking or splitting; furthermore, a method of construction that results in articles that are light in weight and of unusual strength, with great flexibility, durability and utility.
Yet another object of the present invention is to so form the edges of the veneer strips that they will have no tendency to cut through the overlying plastic sheets under the action of bonding pressure and heat in the press.
In accomplishing the above mentioned and other objects of the present invention, I have provided the improved details of construction, the preferred forms of which are illustrated in the accompanying drawings, wherein-- Fig. 1 is an elevation of an article such as a folding drapery, or door that is made in accordance with the States Patent present method and embodies the novel features of the present invention therein.
Fig. 2 is an enlarged cross-sectional view of adjacent veneer strips, particularly showing the plastic sheets that overlie and are bonded to their opposite surfaces and which provide the hinge-like connections between strips that gives the article its foldability.
Fig. 3 is an enlarged cross-sectional view of one of the pliable joints between wooden strips.
The various articles of manufacture, such as draperies, doors, blinds, partitions, and the like to which this invention relates, can be made in various sizes and can be designed as required for various uses. The thin wooden strips of veneer used in their manufacture may be cut to various widths to suit desires or uses and to various thickness, depending on the kind of Wood and the uses to which the article is to be put. Such articles may be equipped as may be required with various suspending or attaching means, referred to as fixtures or hardware, for their support and operation. However, since these parts and their mode of application and use forms no part of the present invention, they have not been herein shown or described.
The present drawings are intended to be representative or typical of the various articles embodied by the invention, and while in Fig. 1 the strips of wood veneer, which I may hereafter refer to as strips, are shown to be vertically disposed, it is to be understood that for some articles they may be horizontally, or diagonally disposed without departing from the spirit of the invention.
While it is not intended to limit the invention to use of any particular material for the making of the strips, it is preferred that they be made of wood veneer and preferably hard wood cut in a manner to emphasize the grain of the wood and to make it most attractive. It has been found that such woods as Philippine mahogany, redwood, walnut, oak and birch are quite desirable and useable for this purpose in consideration of the heat and pressure treatment to which it is subjected.
The strips, for various articles now anticipated vary in width from 1" to 8", and in thickness from .001" to .016, depending on uses, desires, and kind of wood employed. Pliability or flexibility is to be a characteristic of the product and therefore the thinner the strips, the more will be the flexibility. The plastic sheets employed for the surfacing and joining of the slats preferably are a clear, pliable polyvinyl resin, from .006 to .008 in thickness. While this particular plastic does not provide as hard a surface as some other plastics, its use is more desirable because of its pliability and lack of brittleness after processing.
Regardless of the sizes or uses of the articles to be made according to this invention, all are of substantially the same construction and employ the same method of manufacture, therefore, the present drawing applies equally to all. Referring now more in detail to the drawings- The strips of wood veneer, referred to as the strips, are herein designated by numeral 10. It is generally the case, but not a necessary requirement, that all strips be of the same Width, and length. It is practically an essential requirement, however, that all be of the same thickness in order to meet proper pressing conditions, as later will be explained.
The preparation of the strips should be carried on in dust free and grease free areas if possible. The veneer sheets from which the strips are made should be sanded to exact evenness and then secured in a power head and gang sawed as a practical method of eliminating untrue edges and variations in widths of strips. The veneer also should be kept dry and maintained at a moisture content of about 3%. To prevent any possible cutting of the plastic sheets by the strips, all the right angle edges of all strips should be beveled ofi at a 45 angle as has been shown at 12 in Fig. 3.
The plastic surfacing sheets employed are designated by numerals 1313. Preferably these are a thermoplastic known by the trade name Resproid, 8 gauge and clear.
To make up an article of the present character, the strips 10 of veneer of width and thickness desired, and coated with a thermo-setting glue which is like or of the character of that later disclosed, are arranged edge to edge between the sheets of plastic 1313 in proper spacing of about as shown in Fig. 3. The pliable hinge-like connection between adjacent strips is designated at and it is formed by'the joined portions of the plastic sheets between the strips. The sheets should extend beyond the ends and edges of the assembled slats. The assembled slats and plastic sheets, disposed between suitable caul plates of stainless steel are then placed between the platens of a hot press.
With the article thus properly in the press, the hot platens are closed at a pressure of about 50 lbs. per
square inch and pressure and heat maintained until temperature in the core reaches about 285 F.; this requiring about 10 minutes. The platen pressure is then increased to about 200 lbs. per square inch but the heat is cut off allowing the product to be baked under pressure to bond the plastic to the wood and cure it. After the temperature has gradually lowered to below 100 F. the press is opened, the article removed and allowed to cool gradually between the cauls.
The pressing pressures and temperatures can be varied very little, in as much as the temperature of 285 F. to 300 F. is the maximum that the plastic sheets will stand without burning. Even at these temperatures the material starts discoloring after about 2 minutes time. The pressures are figured to a point of preciseness and judged according to the density of the woods being used -each wood having a difierent yielding point-and it is from the yielding point on, that the pressure is increased to compress the wood and the plastic to a degree of .004 inch less than the starting thickness.
Under this pressing operation, the plastic sheets are bonded to the wood and between the wood strips they unite with each other as seen in Fig. 3. This connection between strips is flexible, strong and durable and permits the desired passage of light therethrough which is desidable when the article is used as a shade or drapery for a window.
It is not desired to limit the article to any specific details of construction other than broadly disclosed in the foregoing description, nor to confine it to any particular materials so long as they may be considered equivalent to those mentioned. The article has various uses and applications.
In order to insure adherence of the plastic surfacing sheets to the wood strips, the strips are given a thin coat of adhesive for example, one made in accordance with the formula below given:
Victor 8S stabilizer .3
The mixing procedure is to mix by stirring rapidly the vinylite resin into of the methyl ethyl ketone. Allow it to stand with occasional stirring until it clear and is free of lumps.
Place the Victor 85 stabilizer into the 10% balance of the ketone and disperse thoroughly with a high speed blender. Cool to 32 F.
Cool the propylene oxide to 32 F. and add it to the chilled mixture above, then stir the mixture to the first mentioned mixture.
Having thus described my invention, what I claim as new therein, and desire to secure by Letters Patent, is:
l. The method of manufacturing foldable draperies comprising assembling a succession of thin, flexible strips of wood veneer of uniform thickness, disposed edge to edge, flatly and in slightly spaced relationship, between two thin transparent sheets of thermo-plastic material, subjecting the'assembled 'sheets and strips to heat and pressure between the platens of a press at a starting temperature of approximately 300 F., and the platen pressure being applied initially at 50 pounds per square inch and maintained until the temperature in the wood strips has reached approximately 285 F., then being increased to approximately 200 per square inch and while the platen heat is discontinued, thus causing a gradual lowering of heat therein, removing the pressed article from between the platens when the temperature therein has lowered to approximately F., and causing the article to cool gradually under atmospheric condition.
2. The method of manufacturing foldable draperies comprising assembling a succession of thin strips of wood veneer of uniform thickness disposed edge to edge and in slightly spaced relationship, and of substantially 3% moisture content, flatly between surfacing sheets of thin thermo-plastic material, placing the assembled strips and sheets between caul plates and subjecting them to heat and pressure between the heated platens of a press; said platens being initially maintained at substantially 285 to 300 F., and closed against the sheets at approximately 50 pounds per square inch, said pressure being retained until the core of the pressed materials is about 285 F., then discontinuing heat in the platen while continually increasing the pressure to 200 pounds per square inch and retaining it until the platens have cooled to about 100 F., then removing the pressure from the pressed materials in the press and while still held between caul plates gradually cooling the material to atmospheric temperature.
References Cited in the file of this patent UNITED STATES PATENTS 2,126,711 Atwood Aug. 16, 1938 2,126,833 Steinberger Aug. 16, 1938 2,667,218 Collins Jan. 26, 1954 2,692,382 Lamkin et a] Oct. 26, 1954