US2018712A - Lumber and article made therefrom - Google Patents

Description

Oct. 29, 1935. A. ELMENDORF LUMBER ANDVARTICLE MADE THEREFROM Filed June 14, 1935 2 sheets-sheet 1 Oct. 29, 1935. A. ELMENDORF LUMBER AND ARTICLE MADE THEREFROM 2 sheets-sheet z Filed June 14, 1933 lsatented Oct. 29, 1935 Application .tune is, ms, semi No. cresca Claims.

The present invention has for its object to produce a simple and novel construction material in the form of thin integral wood panels or sheets, comprising narrow strips arranged edge to edge and exibly connected together, whereby warping of the panels or sheets is avoided and capacity for expansion and contraction across the grain of the wood is provided.

in carrying out my invention I cut part way through the thickness of a sheet or panel of wood along `parallel lines extending from. end to end in the general direction oi' the grain of the wood, thereby dividing the sheet or panel superficially into a series of narrow strips. The sheet or panel is then stressed across the grain to the rupture point, causing the comparatively thin connecting webs between the strip-like sections to divide themselves into small strands each attached at its ends to both of thee-adjacent sections. The cutting and the rupturing may conveniently be performed as a single operation. Thus, by using a knife wedge=shaped in cross section and cutting into the wood iar enough, but only far enough, to rupture the remaining uncut depth, the connesting strands between the narrow wood strips are produced as part of the cutting operation. The strands hold the sections of the sheet or panel together; destroy the capacity o the sheet or panel to warp; and permit the sheet or panel to be stretched, if desired, across the grain until there appear between adjacent strips or sections distinct gaps across which the strands extend.

It will be obvious that my improved material lends itself to a great variety of uses. Thus, a flooring may be made of wood of a proper kind, stretched so as to open definite gaps between the strips and having the gaps illled with an eiastic material bonded to the wood; thereby making possible the use of wide, thin floor boards that would otherwise be useless for that purpose. Made in sumciently large sheets and` of cheap wood, faced on one side with strong paper, or the like, my improved material may be employed to advantage to form inexpensive foldable boxes or shipping containers.

Although the invention is not limited to these particular fields, it may be said to have for an object the production of a novel flooring material and, for another object, the production of a novel box or shipping container.

In making a flooring material, wood sheets or panels, preferably fromone-eighth to one-quarter of Van inch thick, properly cut and expanded so as to open up gaps between adjacent strips, are preferably pressed down upon a body of plastic material; causing the lling material to rise into and ll the gaps. The filling material, in order to obtain the full advantages of my invention, must be elastic and of a type that bonds itself to the wood, thereby preventing the opening of cracks under subsequent expansion `and contraction of the wood. The filling material should also be wa.- terprooi. I have found that rubber in latex form answers the requirements just enumerated, and I therefore prefer to employ such latex as the filler, 5 mixing with the latex a substance that will harden the mass sumciently to permit sanding of the door. Fm'thermore, the under side of the oor board as a whole is preferably waterproofed; this being conveniently accomplished by giving it a l0 surface coating of latex, or by gluing the board to waterproofed felt or the like. 1f the wood be very dry, having a moisture content of not more than three or four percent at the time of manufacturing the ooring material, and is backed as l5 aforesaid, the board develops a slightly curved shape, the exposed wood face being on the convex side. Such a board, when applied to a foundation, can be held down in a flat condition, without the use of weights, by means oi ordinary linoieum cements.

The various features of novelty whereby my invention is characterized will hereinafter be pointed out with particularity in the claims; but, for a full understanding of my invention and oi' 25 its objects and advantages, reference may be had to the following detailed description taken in connection with the accompanying drawings, wherein:

Figure l is a plan view of a thin panel oi wood slitted part way through the same; Fig. 2 is a section, on a greatly enlarged scale, on line 2 2 of Fig. l; Fig. 3 ls a view similar to Fig. 2, showing the condition of the panel after the rupturing of the connecting webs between the strip-like sections and the stretching of the panel to open up gaps therein; Fig. 4 is a top plan view of the fragment shown in Fig. 3; Fig. 5 is a section similar to and on the same scale as Figs. 2 and 3, illustrating a panel in the condition that itis in after it has been stressed across the grain to the rupture point and has then been glued to a paper backing; Fig. 6 is a view similar to Fig. 3, showing the gaps illed with a suitable filling material; Fig. 7 is a view similar to Fig. 6, showing the ll- 45 ing material continued over a face of the panel to form a facing layer; Fig. 8 is a perspective View of a fragment of a completed flooring board or panel; Fig. 9 is a cross section on the same scale as Figs. 6 and 7 through the flooring board or panel, 50 showing only a fragment thereof; Fig. 10 is a View similar to Fig. 9, showing the board or panel bent without opening up the joints; Fig. 11 is a more or less diagrammatic view illustrating a. method of producing the material of Fig. 8; Fig. 12 is 55 a perspective view of a box or shipping container embodying the present invention. in one of its forms; Fig. 13 is a section on line i3-l3 of Fig. 12, on a larger scale; Fig. 14 is a section on line i4i4 of Fig. 12, the scale being the same as that 6o of Fig. 13; `.and Fig. 15 is a transverse section through the panel forming the body portion of the box. at the point where a corner is to appear when the panel is folded.

Referring to Figs. 1-4 of the drawings, I represents a thin panel of wood which will usually be thick veneer. By means of slitting cutters, I cut part way through the same along parallel lines 2, 2 extending from one end to the other. The cutting may be done from one or both sides, as long as the result is to divide the wood into strips connected by comparatively thin web portions. In Figs. 2-4 the cuts are shown as extending inwardly toward the center from both sides or faces, leaving unsevered web portions 3.

'Ihe panel is then stressed transversely of the 'grain to the rupture point, rupturing the web portions and dividing or partially dividing them into strand-like elements. The material may now be expanded as illustrated in Figs. 3 and 4, producing comparatively wide gaps 5 across which extend the strands 6 by which the strip-like sections of the panel are held together. The strands are, of course, spaced apart from each other so that the gaps or passages now extend entirely through the wood.

In Fig. 5 I have illustrated a material that may be used in the construction of boxes or the like. The panel 1 may be a veneer of' cheap wood having any desired thickness. Veneer about threesixteenths of an inch thick is suitable for use in the construction of the majority of boxes or containers. It is unnecessary, for this purpose, to open up gaps in the wood, and therefore the panel is left in the condition to which it is brought when stressed transversely of the grain to the rupture point; the cuts or slits remaining practically closed, as indicated at 8, the strands into which the connecting webs 9 have been divided being still in contact with each other and not yet having been spread apart from each other. Glued toone face of the panel is a sheet I Il of tough paper or the like.

In Fig. 6 there is shown a panel II which. after having been brought to the condition illustrated in Fig. 3, has the gaps therein filled with a suitable flling material, as indicated at I2. The filling material is introduced into the gaps in a plastic condition and flows around the connecting strands across the gaps, causing these strands to be embedded within the filling material. The filling material, for most purposes, should be elastic and of such a character as to enable it to bond itself with the wood. I prefer to use rubber latex which is not only elastic but adheres strongly to the wood. The filling in each gap may be regarded as an elastic membrane bonded to the edge faces of the strips between which the gap lies. In most cases there should be mixed with the latex a powdered or granular material such as ground mica, talc, or other suitable finely divided solid mineral. The addition -of such minerals to the latex greatly facilitates the sanding of the boards or panels in commercial sanding machines.

In order to insure that the filling material shall form solid bodies or membranes in the gaps in the wood, I prefer that the wood be pressed down upon a mass or body of the filling material while the latter is in a plastic condition, causing the latter to be forced up into the gaps from below. I shall refer again to this step hereafter.

In Fig. 7 there is shown a construction like that of Fig. 6, excepting that there is on one side of the panel a flexible facing I3 which may be a thin layer of the same material as that which fills the gaps.

In Figs. 8-11 I have illustrated what I regard as the preferred form of panel, sheet, or board for use as a flooring, and the method of making 5 the same. Referring to these figures, I4 is a sheet of flexible backing material, such as waterproofed felt. Overlying and glued to this sheet is a thin board of wood that has been treated as heretofore described, to transform it into a series of 10 parallel strips I5, I5 spaced a short distance apart from each other, but being connected together by strands of Wood I 6 extending across the gaps I1 between the strips. The completed product is shown in Fig. 8, while Fig. 11 illus- 15 trates the preferred method of making it. When the backing layer I4 is felt saturated with asphalt, the face toward the wood is preferably sized as, for example, with an oil size, to facilitate the bonding thereto of the adhesive that zo unites the felt and the wood. This bonding may be effected still more readily and successfully by applying to the sized face of the backing a thin layer of casein glue. Upon the glue is placed the plastic latex, preferably by depositing small g5 masses, as indicated at I9 in Fig. 11, to avoid working the latex as is the case when the latex is spread as a thick uniform coat. In any event, after the latex has been applied to the backing, the wood board or panel is laid upon the same and forced down with suflicient pressure to cause the latex to fiow up into the gaps or passages through the wood and create elastic membranes I2 bonded to the ewood. Some of the latex remains between th`yiood and the backing and 35 forms with -the casein glue a thin glue layer 20.

The gaps or passages through the wood in such embodiments of my invention as those illustrated in Figs. 6 and 7 are also preferably filled in4 the manner just described, namely, the wood o being pressed down upon a mass of the latex compound or mixture.

Instead of filling the joints between the strips of the material shown in Figs. 6, 7, and 8 with latex, I may employ a drying oil or oils as, for 5 example, China-wood oil. Wherea drying oil is used it may be deposited on the upper face of the wood panel and be caused to enter the joints by running a scraper across the surface of the Wood. Compositions containing China-wood oil, 50 applied in this way, not only fill the joints with elastic membranes bonded to the wood, but they also serve to give a finish to the wearing face of the panel. Ordinarily there must be several applications of the drying oils to effect a complete 55 filling of the joints.

As heretofore stated, the elastic membranes I2 are bonded to the wood, so that the Wood strips may expand and contract without opening cracks between them. Also, if the board or panel is bent, 60 as indicated in Fig. 10, the elastic membranes stretch in conformity with the altered shapes of the passages through the wood, but remain bonded to the wood and do not separate therefrom.

The boards or panels of Figs. 6, 7, and, 8 may all be used as fiooring, although those of Figs. 7 and 8 are the bettersuited for application to damp foundations. Not only do the waterproof backings in the constructions of Figs. 7 and 8 prevent moisture from reaching the wood from beneath. but they serve also as cushions which compensate for irregularities in the surface contour of the foundation on which the flooring rests.

In Figs. 12-15 I have shown a novel box construction employing plain wood panels that have 75 been slit into strips connected together by strands and faced on one side with tough paper. The

strips have no appreciable gaps between them and the strands still remain in contact with each other and form between the strips connections that still have the appearance of webs. The body of the box is composed of a single panel, the wood veneer being indicated at 25 and the paper at 26. The slits or cuts 2l are shown as extending into the wood from one face only. This composite sheet may conveniently be produced by ilrst bringing the veneer and the paper facing together with wet glue between them, and then cutting the veneer in such a manner as to eiect the rupture of the depth left uncut in the wood. By this method, the paper prevents the individual strips from separating and causing appreciable gaps to be formed.

V-shaped grooves 2B are cut into the wood element of the composite sheet, along lines paralleling the slits 21, wherever the panel requires bending to produce a corner of the box. In the arrangement shown, the box is four-sided, so that the panel has three of these V-grooves and may therefore be folded into the form of a square or rectangular shell open at both ends. The joint between the meeting ends of the folded panel is covered with a strong tape 29,- preferably of cloth, the tape being glued or cemented to the panel. One of the sides of the shell forming an end of the panel serves as the top or cover of the box, and therefore the tape is applied only at the time the box is closed upon its contents.

At the long edges of the panel, namely, along the edges that constitute the ends of the side walls of the shell or body member I place suitable cleats which cooperate to form strong end frames. Each cleat is made in four sections which, in the arrangement shown, are fashioned at their ends to produce miter joints when the panel is folded into shell form. Each cleat is composed of a core 30 of wood, square or rectangular in cross section; three sides of the core being covered by the panel material. The panel is made wide enough so that by cutting parallel with each long edge two of the V-grooves, properly spaced, and cutting V-shaped sections bodily out of the panel in registration with each transverse line of fold, the side marginal portions of the panel may be folded or wrapped around the core members: each core member and the enclosing elements thereafter being secured together, preferably by staples 3|. The loose end Walls or box heads 32 t into the shell against the inner edges or faces of thecleats. These end walls or heads may be constructed of any suitable material which I have illustrated as consisting of wood veneer faced on both sides with strong paper.

The box is shipped in three flat pieces, namely, the pre-formed body panel and the two ends or heads, and is set up at the point of use. In setting up the box, the body panel is folded along the lines of two of the transverse V-grooves and the end walls or heads `are set into the U -shaped structure thus produced. A few light nails are then driven through the end walls or heads into the upright cleats which are the cleats at the ends of the side walls of the box. After the box has been filled, the fourth side is folded down and is secured with the tape 29. The box may be reenforced with suitable ties or straps 33.

The material of which the body portion of the box is made lies fiat before being folded, even though the wood veneer originally was badly buckled or warped. Furthermore, this material may be made in long sheets by a continuous process of gluing pieces of veneer edge to edge upon a sheet of paper as the latter is unwound from a roll. After the wood has been treated as heretofore explained, the composite sheet may 5 be wound up in roll form. Consequently, this material may readily be manufactured by a continuous process; the paper being progressively unwound from a roll; the veneer being applied to the paper as the latter is unwound; the com- 1o posite sheet being operated upon to slit the veneer and stress it transversely of the grain to the rupture point; and the completed product being then progressively rolled up. The process of manufacture 'of the composite material is, of l5 course, very rapid when it is done continuously. However, in order that it may be continuous and not intermittent, as will be the case when the gluing is done in hot presses, I employ a glue that permits instantaneous gluing to be effected. So- 20 dium silicate is such a cement or glue. The sodium silicate is spread on the paper just an instant before the wood is applied, whereupon the passing of the paper with the overlying veneer through pressure rolls causes the veneer and the 25 paper to be firmly cemented together. Not more than a few seconds should elapse between the time of spreading the sodium silicate on the paper and the time of pressing the veneer against the same. 30

A box, the body of which is constructed of my improved material, is strong and durable. The paper gives diagonal bracing tothe wood. The wood protects the paper from contact with the contents of the box so that, if the contents are 35 damp, as in the case of meat, the box is not weakened as it is in the case of a berboard box containing damp goods. It will also be seen that by constructing the end cleats as shown, the tension of the paper at the ends assists the shear strength 40 to keep the end walls or heads from being pushed out.

I claim:

1. A board of wood cut partly through the same along parallel lines extending in the gen- 45 eral direction of the grain from one end of the board to the other, the uncut portions of the board in the planes of the cuts being ruptured along lines following the grain into strand-like portions, whereby the board in eect consists of 5o a series of parallel strips connected together at their edges by strand-like cross pieces.

2. 'Ihe method of treating a board, which consists in cutting partly through the same along parallel lines extending in the general direction 55 of the grain from one end of the board to the other, and then bending the board along each of said lines until the uncut portion there is ruptured and forms connecting strands between the parts of the board on opposite'sides of that line. 60

3. A board of wood cut partly through the same along parallel lines extending in the general direction of the grain from one end of the board to the other, the uncut portions of the board in the planes of the cuts being ruptured 65 along lines following the grain into strand-like portions, whereby the board in effect consists of a series of parallel strips connected together at their edges by strand-like cross pieces, the passages through the wood formed by the cuts and 70 the spaces between said cross pieces being lled with an elastic material bonded to the wood.

4. A board of wood cut partly through the same along parallel lines extending in the general direction of the grain from one end of the 75 board to the other, the uncut portions of the board in the planes of the cuts being ruptured along lines following the grain into strand-like portions, whereby the board in effect consists of a series of parallel strips connected together at their edges by strand-like cross pieces, the passages through the wood formed by the cuts and the spaces between said cross pieces being filled with a material containing rubber latex.

5. A board of wood cut partly through the same along parallel lines extending in the general direction of the grain from one end of the board to the other, the uncut portions of the board in the planes of the cuts being ruptured along lines following the grain into strand-like portions, whereby the board in effect consists of a series of parallel strips connected together at their edges by strand-like cross pieces, the passages through the wood formed by the cuts and the spaces between said cross pieces being filled with rubber latex mixed with a finely divided solid.

6. A board of wood cut partly through the same along parallel lines extending in the general direction of the grain from one end of the board to the other, the uncut portions of the board in the planes of the cuts being ruptured along lines following the grain into strand-like portions, whereby the board in effect consists of a series of parallel strips connected together at their edges by strand-like cross pieces, and a layer of facing material covering a face of the board.

7. A board of wood cut partly through the same along parallel lines extending in the general direction of the grain from one end ofthe board to the other, the uncut portions of the board inv the planes of the cuts being ruptured along lines following the grain into strand-like portions, whereby the board in eiect consists of a series of parallel strips connected together at their edges by strand-like cross pieces, the passages through the wood formed by the cuts and the spaces between said cross pieces being filled with an elastic material bonded to the wood, and an elastic membrane covering and adhering to a face of the board.

8. A board of wood cut partly through the same along parallel lines extending in the general direction cf the grain from one end of the board to the other, the uncut portions of the board in the planes of the cuts being ruptured along lines following the grain into strand-like portions, whereby the board in effect consists of a series of parallel strips connected together at their edges by strand-like cross pieces, and a mixture of latex and finely divided solid material forming an elastic membrane covering a face of the board and filling`the passages that are caused to extend through the board by the 'cutting and rupturing thereof as aforesaid.

9. A board of wood cut partly through thesame along parallel lines extending in the general direction of the grain from one end of the board to the other, the uncut portions of the board in the planes of the cuts being ruptured along lines following the grain into strand-like portions, whereby the board in effect consists of a series of parallel strips connected together at their edges by strand-like cross pieces, and a sheet of fibrous material covering a face of the board and secured thereto by an adhesive material.

10. A board of wood cut partlyl through the same along parallel lines extending in the general direction of the grain from. one end of the board to the other, the uncut portions of the board in the planes of the cuts being ruptured along lines following the grain into strand-like portions, whereby the board in eiect consists of a series of parallel strips connected together at 5 their edges by strand-like cross pieces, a sheet of fibrous material underlying the board, and an elastic substance adhering to said sheet and filling the passages through the wood and the spaces between said cross pieces. m

11. The method of making a board exible and non-warping which consists in cutting partly through the same along parallel lines extending in the direction of the grain from one end to the other, and stressing the board transversely to 15 the rupture point of the connecting pieces between the strips or sections defined by said lines to divide the board into strips held together by strand-like cross pieces.

12. The method of making a board flexible and non-warping which consists in cutting partly through the same along parallel lines extending in the direction oi' the grain from one end to the other, stressing the board transversely to the rupture point of the connecting pieces between the strips or sections defined by said lines to divide the board into strips held together by strand-like cross pieces, and filling the spaces between the strips with an adhesive material that is flexible and elastic when it has set.

13. The method of making a board flexible and non-warping which consists in cutting partly through the same along parallel lines extending in the direction oi' the grain from one end to the other, stressing the board transversely to the rupture point of the connecting pieces between the strips or sections defined by said lines to divide the board into strips held together by `strand-like cross pieces, and filling the spaces between the strips with rubber latex mixed with 40 finely divided solid matter.

14. The method of making a board flexible and non-warping which consists in cutting partly through the same along parallel lines extending in the general direction of the grain from one end to the other, stressing the board transversely to the rupture point of the connecting pieces between the strips or sections defined by said lines to divide the board into strips held together by strand-like pieces and produce open passages extending entirely through the board between the strips, coating a sheet of waterproofed felt with glue, depositing on the glue layer an adhesive material containing latex, and pressing the said board down on the sheet of felt with sufficient force to cause the saidadhesive to iiow up into said passages.

15. The method of making a board flexible and non-warping which consists in cutting partly through the same along parallel lines extending in the general direction of the grain from one end to the other, stressing the board transversely to the rupture point of the connecting pieces between the strips or sections defined by said lines to divide the board into strips held together by strand-like pieces and produce open passages extending entirely throirgh the board between the strips, coating a sheet of waterproofed felt with glue, depositing on the glue layer an adhesive material containing latex, and pressing the said board down on the' sheet of felt with sufficient force to cause the said adhesive to ow up into and completely ll said passages.

ARMIN ELMENDORF.

Images