US2689592A - Apparatus for making patterned stable plywood - Google Patents

Description

Sept 21, 1954 H. c. soEHNER 2,689,592 APPARATUS FoR MAKING PATTERNED STABLE PLYwoon `original Filed March 18, .1949

:inventor HOWARD 6. SGEHA/ER (Ittomeg Patented Sept. 21, 1954 APPARATUS FOR MAKING PATTERNED STABLE PLYWOOD Howard C. Soehner, Louisville, Ky., assignor to The Mengel Company, Louisville, Ky., a corporation of New Jersey Original application March 18,` 1949, Serial No. 82,103. Divided and this application June 11, 1949, Serial No. 98,464

2 Claims. (Cl. D14-281) This invention relates to improvements in apparatus for forming a pattern of design in ply wood concurrently with the making on a commercial production basis, of stable plywood panels from Veneers that will retain substantially their original areas and a planar state indefinitely by reason of the fibres thereof having been deprived of their natural properties that cause warpage, shrinkage and twisting without developing noticeterned plywood by a caul plate I4 and the depending teeth sunken into the face veneer by requisite pressure and heat applied by and through platens I5, I 5A.

In Figs. 1 and 2, caul plate It, the flat faced teeth depending therefrom are disposed in several series, to Wit: I6, IGA, I'I, IIAy I8, ISA et cetera with a relatively large space or gap between the juxtaposed ends thereof. This gap exy able checks or splits in the surface of iinished l0 tends beyond the root of the teeth in order to propanels. This is a division of my application, Sevide a channel I9 that is free to function as such rial Number 82,163, filed March 18, 1949, and en-` for the liberation of steam and vapors expelled titled Method of Making Plywood and a Product from the application of heat. Thereof. It will be observed that in this instance these In the aforesaid application there are disclosed teeth penetrate the face veneer beyond the medial apparatus, the method of using the same to proplane thereof and thereby apply a vastly greater duce panels and two patterns therefor. area of heated surface to the wet veneer, thus The object of this invention is to provide a producing a blast `of steam greatly in EXCESS Of novel platen or caul plate for use in a press prothat expelled from caul plates or platens not vided with means for heating the same during equipped with the teeth adverted to above. In production of panels of the types shown therein order to prevent blistering of the surface of the and reproduced herein, and kindred types. face ply, channels I9 are provided. As shown in Another object of this invention is to construct the drawing these transverse channels have a said platen or caul board so that the same can depth which is greater than that of the valleys liberate instantaneously the steam and vapors between the teeth and thus freely communicate from veneers having a moisture content near or with the ambient atmosphere even when the caul above the libre saturation point (hereinafter teeth are sunken into the veneer. It should be sometimes referred to as wet veneer) when sudnoted that very short teeth are employed and denly subjected to high temperatures and without that each tooth is flanked by channels thereby forming blisters or producing cracks or voids that providing an easy exit for the steam that stems may be caused from trapped or conned steam. from the moisture entrapped in and between the These and other objects will be apparent to wood iibres, none of which steam has to travel those skilled in the art as the following descripmore than half the length of a tooth before reachtion is read in connection with the accompanying a free escape t0 the ambient atmOSphBre- It ing drawings, on an enlarged scale in terms of a is evident that it is not necessary to have teeth plywood panel, in which; of any particular shape or depth, and the pene- Figure l is a perspective sectional view through tratiOn requirements may also vary, as more fully a press closed on a fragment of an assembly of described in my application Serial Number 82,103, veneers for making a threep1y panel on which led March 18, 1949, and entitled Method of is superimposed one form of my novel caul plate Making PlyWOOd and a Product Thereof. as these elements appear after requisite pres- The pattern 0f the Gaul plate ShOWIl in Fig. 3 sure and heat have been applied thereto for comis identical in principle to that explained above. pleting a panel. This gure has been included to show that varia- Figure 2 is a, perspective view of a, fragment of tions can be indulged. A detailed description is the caul plate shown in Fig. 1. not regarded as being essential to grasp the teach- Figure 3 is a perspective View of another form ings thereof. of caul plate, however, of the same general type. i The main feature in caul plate 2u illustrated Figure 4 is a perspective view of another form in Fig. 4, which is a departure in structure and of caul plate and of a different construction, pattern for plywood to be formed thereby, from Figure 5 is an end elevation of a fragment of 50 the simpler type shown in the other figures, conthe caulplate shown in Figure 1 partially sunk sists of ducts and channels in the body of Said into the top veneer thereof. plate. Here are inserts 2 I, 2| overlying and dis- In Fig. 1, numerals I0, I I and I2 designate reposed at right angles to major channels 22, 22 spectively face veneer, core and bottom veneer and in which inserts are smaller channels or in process of being formed into a fragment of patgrooves 23, 23 in the outer surface that communicate through ducts 24, 24 to minor channels 23A, 23A, on the inner faces of these inserts. These latter channels lead to the major channels there by carrying forward the same principle for vent ing the steam as explained for Fig. 1. Whether the teeth are inserted partially or entirely into the veneer, channels 23, 23 are not completely closed. Obviously channels 22, 22 are always open to the ambient atmosphere.

It should be noted that the teeth in the inserts are shown to have sharp edges to facilitate cutting the wood fibres perpendicularly to the grain thereof, While the other series of teeth are fashioned with flat faces to compress the nbres falling thereunder. It should also be noted that the teeth in the inserts do not project as far as the teeth which are parallel with the wood fibres.

While it will be apparent that the disclosed embodiments of my invention together with the illustrated instrumentalities and types of products produced thereby are well calculated tofulnll adequately the objects and advantages primarily stated, it is to be understood that the invention is susceptible of Variations, modications and changes within the spirit and scope of the subjoined claims.

W hat I claim is:

1. In a platen, caul plate or the like for forming patterned depressions in the exposed surface of the outer Veneer of plywood while it has a high moisture content; a working face having several series of spaced-parallel teeth, said teeth being interrupted by and terminating in transverse channels formed within the platen and having a depth greater than that of the valleys between the teeth, said channels communicating with the ambient atmosphere when said teeth are heated and sunken into the veneer sufficiently to compress all of the fibers embraced by the contacting surfaces of the platen, whereby the liberated steam is compelled to flow to and through the said channels to the atmosphere.

2. In a platen or caul plate or the like for forming depressions in the outer veneer for plywood or the like While the latter has a high moisture content; major ducts extending through the body of the platen, a working face thereof, said workingl face having a plurality of short teeth that terminate in minor transverse channels which communicate at spaced points with vertical ducts that in turn communicate with said major ducts for discharging steam liberated at the middle portions of the veneer when said teeth are hot and sunken into said outer surface sufficiently to compress all of the fibers embraced by the contacting surfaces of the platen, whereby the liberated steam is compelled to ilow through the said channels and ducts to the atmosphere.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 331,769 Compton ec. 8, 1885 1,794,194 Meyercord Feb. 24, 1931 1,984,384 Shefeld Dec. 18, 1934 2,245,170 Non Ende June 1o, 1941 2,268,477 Elmendorf Dec. 3o, 1941 2,332,886 Basler Oct. 26, 1943 2,471,932 Chaplin May 31, 1949 2,514,318 Elmendorf July 4, 1950 FOREIGN PATENTS Number Country Date '731,465 France Sept. 3, 1932 nh er

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