US1869957A - Method and apparatus for the formation of plywood - Google Patents

Description

T. w. DIKE 1,869,957

METHOD AND APPARATUS FOR THE FORMATION OF PLYWOOD Aug. 2, 1932.

Filed Feb. 28, 1931 5 Sheets-Sheet 1 v Y A TTORNEYS.

1932. 'r. w. DlKE 1,869,957

METHOD AND APPARATUS FOR THE FORMATION OF PLYWOOD Filed Feb. 28. 1931 5 Sheets-Sheet 2 INVENTOR:

I M V w ATTORNEYS.

Aug. 2, 1932. w DIKE 1,869,957

METHOD AND APPARATUS FOR THE FORMATION OF PLYWOOD Filed Feb. 28, 1931' 5 Sheets-Sheet 3 1932. T. w. DIKE 1,869,957

METHOD AND APPARATUS FOR THE FORMATION OF PLYWOOD Filed Feb. 28, 1931 5 Sheets-Sheet 4 Fin; 12-

ATTORNEYS.

Aug. 2, 1932.

METHOD AND APPARATUS FOR THE FORMATION OF PLYWOOD v T. w. DIKE Filed Feb. 28, 1931 5 Sheets-Sheet 5 IN VEN TOR.

A TTORNEYS.

Patented Aug. 2, 1932 UNITED STATES PATENT OFFICE THEODORE WILLIAMS IDIKE, OF NEW WESTMINSTER, BRITISH COLUMBIA, CANADA, ASSIGNOR TO I. F. LAUCKS, INC., OF SEATTLE, WASHINGTON, A CORPORATION OF WASHINGTON METHOD AND APPARATUS FOR THE FORMATION OF PLYWOOD Application filed February 28, 1931. Serial No. 518,944.

This invention relates to gluing methods and apparatus, and, more particularly, to methods and apparatus for the formation of plywood.

The present application is, in part, a continuation in part of my copending applications Serial No. 335,998, filed January 28, 1929, Serial No. 455,97 8, filed May 26, 1930, Serial No. 36,813, filed May 28, 1930, and Serial No. 456,814, filed May 28, 1930.

An object of the invention is'to provide improved methods and apparatus whereby plywood may be formed in a particularly expeditious and effective manner.

A further object is to provide a method of forming plywood whereby the same may be formed in such manner as to eliminate unnecessary time, labor and expense in the operform.

Another object is directed to the provision of apparatus particularly adapted for performing methods such as contemplated by the invention.

Still another object is to provide apparatus whereby there may be applied efficiently and expeditiously to materials to be glued an adhesive base in discrete particle form, and particularly in powdered form.

Another object is directed to the provision of improved apparatus for the speedy and eflicient application of gluing materials to blanks in a desired manner.

Other objects of the invention will in part be obvious and will in part appear hereinafter. 7

The invention accordingly comprises the several steps and the relation and order of one or more of such steps with respect to each of the others, and the apparatus embodying features of construction, combinations of elements and arrangement of parts which are adapted to effect such steps, all as exemplified in the following detailed disclosure, and the scope of the application of which will be indicated in the claims.

Fig. 1a is a side view showing somewhat diagrammatically a form of apparatus similar to that shown in Fig. 1, but showing the coating of plies of different thicknesses;

Fig. 2 is a plan view thereof;

Fig. 3 is a side view of a form of apparatus adapted for use in the formation of multiple ply panels;

Fig. 3a exemplifies an assembly formed by apparatus such as illustrated in Fig. 3;

Fig. 4 is a side view of apparatus similar to that shown in Fig. 3;

Fig. 5 is an enlarged detail side .view partly broken away showing the exemplified apparatus for disseminating a liquid;

Fig. 6 is a sectional View along the line 6-6 of Fig. 5;

Fig. 7 is a detail plan view on an enlarged scale showing the apparatus for disseminating a powder;

Fig. 8 is asectional view taken along the lines 8-8 in Fig. 7; v

Fig. 9 illustrates a further modified form of method and apparatus wherein powder and liquid are mixed before they reach the panel; i

Fig. 10 is a fragmentary side view illustrating still another modification;

Fig. 11 is a similar view illustrating a further modification;

Fig. 12 is a similar View illustrating another modification;

Fig. 13 is a view on a smaller scaleillustrating the formationof a three-ply panel by means of apparatus of the nature-shown in Figs. 11 and 12;

Fig. 14 is a. plan View illustrating a method and means for controlling the amount of adhesive supplied to plies;

Fig. 15 is a partly sectional view along the lines 1515 of Fig. 14;

Fig. 16 is a view illustrating one type of ply which may be coated in accordance with the invention;

Fig. 17 illustrates a method and means particularly adapted to the formation of assemblies including plies as illustrated in Fig. 16;

Fig. 18 illustrates another modified form of method and apparatus embodying the invention; and

Fig. 19 illustrates a further modified form.

Ordinary commercial methods of forming plywood, moreover, have a considerable number of drawbacks which, while recognized for many years, are still inherent in common methods. Among thesearethe failure to attainanything approaching a uniform glue spread in practical procedures, the diificulties in safely handling available veneer sheets, and the practical limitations in varying procedures as required in making up different forms of plywood. Commonly, rotating means such as glue rolls, "or in some instances a glue brush, is utilized to apply .a liquid glue. Neither gives a uniform spread, and the glue rolls, while somewhat more eiiicient in this and other respects, are, in spite of their widespread use, far from attaining the desired results. The veneer available for the gluer is commonly Warped or buckled throughout its extent, so that it is practically impossible for a rotating brush or rollto apply liquid glue uniformly. Furthermore, itis a readily breakable product, particularly when pre-dried, which is an important desideratum if the escape of a large excess of glue into the body of the wood is to be restricted. The pressure which may be applied by glue rolls is accordingly limited. Indeed, there is a high proportion of breakage in many cases where the rolls are set no tighter than just enough to feed the plies, and the pressure limitation further militates against a uniform spread. Again it is commonly found necessary to groove the rolls. which results in a pronounced pattern in the spread. Even with smooth rolls the glue is deposited in a pattern rather than as a continuous uniform film over the surface. The nature of the pattern consists of alternate hills or ridges of glue separated by valleys with the surfaces merely wetted by a thin film of glue, and a marked excess of glue must be supplied to accomplish any material reduction of this deficiency. Furthermore, the veneer sheets will vary at least fivethousandths of an inch in thickness; and usually more, and even this variation is sufficient to cause unevenness in spread by rolls which will apply a substantially even coating to paper. When plies of different thicknesses are to be glued foruse in the same panel, or in successive quantities of panels,

either two machines must be used or discon-' tinuous operation to allow for adjustments must be resorted to. Moreover, because of the pressure restrictions a change in the viscosity of the glue or a substitution of rolls having diflerently spaced grooves is commonly necessary when a change in spread, i. e., in the amount of glue applied to a given surface area, is desired. Indeed, accuracy of control of the spread is practically impossible because of its dependence on the precise pressure exerted by the rolls at any adjustment, which as a practical matter will be only roughly accurate. Ordinarily the rolls are adjusted to provide an opening somewhat greater than the thickness of the veneer, and any curvature in the veneer or variation in its thickness, or a maladjustment of the rolls increases the unevenness of the deposit, with consequent lack of uniformity of adhesion, and when two sides of the veneer are spread, causes further variation as between the glue lines. Also, disturbance of the spread in assembly manipulations and smearing and stickiness seems .to be unavoidable in such processes.

In view of the foregoing, it will be seen there has existed for some years a need for a continuous gluin method whereby quality products embodying pre-cut veneer and the like may be produced in a continuous and eflicient manner. In accordance with the present invention methods and means to this end are provided, the adhesive material, in discrete-particle, -ordinarily powdered, form, being desirably applied without contact with the surface of the plies.

With the foregoing and other ends 1' 11 View, the invention contemplates the provision of methods and means whereby gluing materials -may be so applied that a plurality of wood plies or the like may be glued and assembled with a minimum amount of labor and in an expeditious manner, such assemblies being efl'ectively formed in a continuous manner whereby the output may be increased and operating cost reduced.

More specifically, the invention contemplates the provision of improved methods and means whereby an adhesive material in discrete particle form may be readily supplied at the glue line. Such adhesive material may comprise any well known or other suitable substance which possesses adhesive properties in its normal state or which is transformed by conditions present in the press, or other bonding means, into a substance having adhesive properties. The adhesive material may be applied in the form of dry particles or of moist particles, and may be otherwise suitably conditioned and admixed with supplemental materials. The invention also contemplates, in certain of its aspects the provision of im roved methods and means for supplying liquid materials at the glue line, and particularly for applying a plasticizing liquid, as in cases where a relatively dry adhesive base is utilized in the formation of laminated materials from materials sufficiently dry so that moisture required for providing plasticization or for the formation of a bond will not otherwise be present at the glue line.

The invention furthermore contemplates the formation of an assembly of plies, such assembling operation taking in many instances the form of sub-steps performed at suitable times during the procedure, and contemplates subjecting the assembled plies to bonding operations in any suitable manner as in a veneer press, many types of which are well known in the art.

Pursuant to the invention, pre-cut wood plies or similar materials may be passed successively through a zone in which a gluing material is being so disseminated as to contact with the surface of the plies as they are passed along. The gluing material so disseminated may be an adhesive material either of the type requiring plasticization by water or other plasticizing agent, or any other type of material, or may be a plasticizing agent or other addition agent, either liquid, solid or any other suitable material, it being understood that in certain of its broader aspects the invention contemplates the application, either separately or together, of any material or plurality of materials, the presence of which at the glue line is desirable in the gluing of wood and the like. For example, there may be provided a disseminator for a powdered adhesive material and a disseminator for an aqueous plasticizing agent, which disseminators may be arranged in any desired relation in respect to the direction of movement of the conveyor. There may be provided means for causing plies to be coated with small particles of a moist glue in a pasty condition. 'A single disseminator for powdered adhesive material may be used in instances where one or another of the plies to be utilized contains sufficientwater 'for the formation of the bond, or when the glue utilized is plasticizable independently of the presence of a liquid agent. Separate conveyors may be used and a disseminator for a powdered adhesive base may be associated with one, and a disseminator for plasticizing agent may be associated with the other, and plies from two conveyors may be laid together after each has passed through the zone of material disseminated in proximity to its conveyor. Many other suitable variations of steps or arrangement of parts may be utilized.

For instance, in the formation of panels of the usual type having three plies, the back plies may be passed through a suitable zone or zones of disseminated materials, a central ply (or core) laid on each, the partial assemblies successively passed through a further zone or zones, and the face plies thereafter put successivelyin position, the cores and the back plies may be passed on the same or separate conveyors through suitable zone or zones of disseminated material, each core laid on a back ply, and a face ply disposed on top; or the cores may be suitably coated on both sides by being passed through suitable zones, and assemblies formed by joining the surfaces of outer plies with the coated surface of the cores. Theformatio-n of each assembly may, as will be seen, include a step performed before the coating of the second surface of the core. Other suitable adaptations of the procedure may occur when more than three plies are utilized in the formation of a panel. Furthermore, although it is ordinarily desirable to pass the plies mder stationary disseminating means, the series of plies may be stationary and the disseminating means moved in a uniform manner in certain instances. Indeed, a large number of variations of procedure is possible without departing from the invention.

There are described below by way of example methods and apparatus embodying the invention and illustrative of the same.

In Figs. 1 and 2 there is shown a conveyor 20 on which there may be disposed manually or by suitable autbmatic means a succession of blanks or plies 21, a pile of such blanks being indicated at 22 as disposed on a table 23 from which they may be successively withdrawn by hand and placed on the conveyor. Above the conveyor is disposed a shaking screen 24 containing a mass of powdered dry adhesive base which may be replenished continuously or from time to time, as desired. The screen may be reciprocated by any type of well known or desired means, one such means being exemplifiedin Figs. 7 and 8, so as to disseminate in a zone traversed by the conveyor a cloud of particles of the adhesive base which will fall on successive blanks 21 as they are carried thereunder at a uniform rate of travel by the conveyor 20. The spread, i. e., the amount of glue applied, may be readily controlled by the relation between the speed of the conveyor and the period of vibration of the screen, one means to this end being hereinafter exemplified. As will be readily appreciated, this method permits the ready control of the size of the particles delivered to the ply to be coated. If desired, the smaller particles may be eliminated by the previous sifting and the larger particles eliminated by the shaking screen 24. In the event that either the blank coated or the blank to be applied to the coated surface contains sufiicient moisture for plasticizing the glue, or in the event that no plasticizing agent is required, all that is necessaryis to apply a second blank to the coated blank. Such second blanks 25 may be taken from a pile 26 and put in place-successively upon coated blanks. Whereupon the plies may be pressed if a complete assembly has been formed, or

the assembly may be suitably completed; as, for example, by passing the assembled plies 21 and 25 again under the screen 24, which, it will be noted, is suflicient-ly above the conveyor 20 to permit this, and applying a further blank; and then pressed.

As above indicated, a desirable feature of the invention is that it permits the coating of plies of different thicknesses by the same mechanism without adjustment. One type of procedure of this nature is indicated. in Fig. 1a, wherein there are disposed. on the conveyor 20 in alternation relatively thick core plies 21a and relatively thick back plies 216 which are carried by the conveyor under the disseminating means 24. After the ,plies are suitably spread a core 21a is placed upon each back ply 21b and a face ply 25a disposed thereupon to form a three-ply assembly, and

the assembly subjected to bonding conditions, as in a plywood press of suitable type.

As indicated in Fig. 3, the apparatus can be readily adapted for the quantity production of multiple ply panels by the use of a plurality of spaced disseminating means. In this figure there is shown a conveyor 27 longerthan the conveyor 20 and equipped.

with a second shaking screen 28 spaced from the shaking screen 24 so as to permit a partial assembly, formed by laying a blank 25 on the blank 21, to pass under the second shak ing screen to receive a coating of an adhesive base, after which a third blank 29 may be taken from 'a piler30 and laid on the blank 25. The assemblies (one o-f which is shown on an enlarged scale in Fig. 3a) will then be ready for pressing into three-ply panels. The apparatus may be similarly modified to permit the assembly of panels composed of four, five or more plies in this or other particular manners.

In instances where it is desired to apply a 'plasticizing or other liquid to the glue line, it is often desirable to similarly disseminate the same in a zone traversed by the moving plies, instead of spreading the liquid directyou the wood. To this end an atomizer or other spray means may be provided. Among other advantages this permits a limited amount of water to be evenly applied to the surface, and, in cases where a plasticizing agent is applied after a dry adhesive base, permits the plasticizing liquid to be put in place without disturbing the coating of thepowder. It is to be appreciated, however, that the plasticizing or other liquid may be applied to uncoated blanks, as well as the blanks in any of avariety of other conditions. "Fig. 4 shows a form of construction gen erally similar to that shown in Fig. 3 e mbodying, in addition to the means for disseminating a powdered adhesive base, an atomizer 31 disposed, in the present instance. beyond the shaking screen 24 in the direction the application of dry particles.

of the movement of the conveyor, and a similar atomizer 32 disposed beyond the shaking screen 28. In this instance the back 21 is moved through the zone in which a cloud. of

powdered adhesive base is being disseminatwater is sprayed into a conduit 36. A draft of air forced through this conduit breaks the spray in a mist or cloud which is blown through a nozzle 37. The disseminated liquid falls, as indicated at 38, on the surface I ofplies carried by the conveyor 20.

The form of means for disseminating a powdered adhesive material is exemplified in greater detail in Figs. 7 and 8. The vibratory screen 24 is supported for recipro cable. movement on arms 39 carried by a frame-work 40. The screen-is attached by means of a link 41 toan eccentrically mounted member 42 carried on a shaft 43 which is connected by means including a belt 44 to a-shaft 45. In the present instance, the g shaft 45 carries wheels 46 which carry the elements of the conveyor 20 by which plies are passed through the zone 24a of powdered adhesive material disseminated by vibratory movements of the screen. Suitable power means (not shown) are, of course, provided 1 for driving the conveyor and the associated mechanism. i

As above set forth, the invention contemplates the application of moist particles of adhesive material to the plies as well as Such a plication may be effected by suitably breaking up and disseminating a pasty mass of adhesive material, or intermingling moisture with dry particles either before or after the initial dissemination of the particles. There is exemplified in Fig. 9 one form of apparatus embodying this feature of the nvention.

In the exemplified form the construction includes a conveyor 20 and a vibratory screen 24 which may be provided with associated parts, all as exemplified in the preceding figures. Adjacent the screen there is disposed an atomizer member 47 comprising a water inlet 48. air draft conduit 49, blower 50 similar to those of the atomizers 31 and 32 and with a nozzle 51 arranged todirect the mist of atomized liquid into the cloud of dissemlnated dry particles fallingfrom the shaking screen. The two disseminated materials are accordingly mixed so that the plies '21 passing through the zone of disseminated particles receive on their upper surfaces a coating of moist particles of adhesive material. It is to be noted in this connection that the use of an air current in the application of a powdered material to a surface, and apparatus therefor, is disclosed and claimed in the copending application of Louis G. Merritt and Ericsson H. Merritt. Serial No. 542,257, filed June 5, 1931, wherein one particularly desirable form of disseminating means is disclosed.

In certain instances, it is desirable that no adhesive material contact with the conveyor elements. One form of apparatus whereby such contactmay be avoided as exemplified in Fig. 10, wherein the zone in which the adhesive material is disseminated is disposed within a space between two'conveyors which the plies bridge as they are passed through the zone. A disseminating means 52 consisting, in the presentinstance, of a vibratory screen similar to the screen 24, for example, is disposed above a space between the. forward end of a conveyor member 53 and the rear end of a conveyor member 54, the plies utilized being of sufficient extent to bridge the gap between these two conveyors. There is exemplified at 55 a ply bridging the conveyors and receiving on its surface a coating of disseminated material 56. There is also exemplified in this figure a catch-pan 57 disposed at the bottom of the zone in which the material not received on the surfaces of the plies may be caught for re-use. A similar catch-pan maybe utilized in connection with other types of apparatus to catch material falling around the sides of the conveyor, for example.

In Fig. 11 there is exemplified a similar construction wherein there are provided bafiies 58 and 59 for the purpose of effectively preventing the disseminated material from spreading sidewise to a point where it will fall upon one of the conveyors. The provision of such baflies is particularly advantageous in instances wherein atomizers are employed to mix a mist with the disseminated powder and there are exemplified in Fig. 11 atomizer nozzles 60 and 61 protruding through the sides of the baffles 58 and 59, respectively.

Powdered material may be supplied to the vibratory screen or other disseminating means in any suitable manner. Preferably, however, it is desirable to provide means for efi'ectuating a continuous and controlled supply of material thereto. One such means is exemplified in Fig. 12, wherein there is provided a hopper 62 having a laterally extended bottom opening 63 through which a limited'amount of glue continuously passes onto a vibratory screen 64 from which it is disseminated into a zone traversed by panels on a conveyor 65.

In Fig. 13 there is exemplified an arrangement embodying certain of the features set forth in Figs. 11 and 12 adapted for the production of a three-ply panel. This apparatus comprises a third conveyor 66, in addition to conveyors 53 and 54, and an additional shaking screen 67, besides the shaking screen 52. The shaking screen 67 is disposed between the ends of the conveyors 54 and 66 and baffles 68 and 69 similar to the baffles 58 and 59 are provided in connection therewith, Hoppers 50 and 71 are provided above the vibratory screens 52 and 67, respectively. A liquid from the tank 72 is conducted through the pipe 73 to pipes 74, one of which enters each of a plurality of conduits 75 leading to nozzles 60, 61, 76 and 77, respectively Each of the conduits 75 is connected by a larger conduit 78 to a blower member 79.

It is often desirable to utilize various amounts of adhesive material in the gluing of various types of materials, and to this end the invention contemplates controlling the spread by varying the amount of adhesive material disseminated in different instances. One means to this end is exemplified in Figs. 14 and 15 wherein the vibratory screen 80 is shown as connected to a cam member 81 carried on a shaft 82. A cone 83 is disposed on this shaft and is connected by means of a belt 84 to an oppositely disposed cone 85 carried on a shaft 86, which is connected to a conveyor shaft 87 by means including a belt 88. A shifter 89, under controlof a handle 90, acts to position the belt 84 to control the relative speed of vibration of the vibratory screen and the speed of movement of the conveyor 91.

lVhile in certain instances it is desirable to apply first a dry adhesive base and then a plasticizing agent to the plies; in other instances, and particularly in the use of warped dry plies, as shown at 92 in Fig. 16, it is desirable to have the surface of the plies wet so thatthe disseminated adhesive material will adhere. evenly thereto. Fig. 17 shows one such arrangement wherein plies 92 are carried by a conveyor 93 first under an atomizing means 94 and then under a means 95 for disseminating a powdered adhesive material.

Another modification is exemplified in Fig. 18 wherein there are utilized two conveyors 96 and 97 having a parallel movement and eachhaving disposed above the same means for disseminating a gluing material, this means consisting, in the present instance, of vibratory screens 98 and 99. A series of plies 100 are taken successively from a table 101 and disposed on the conveyor 96; and simultaneously a series of plies 102 are taken from a table 103 and disposed on the conveyor 97. After both sets of plies have passed through the zones of material disseminated by the respective vibratory screens, each ply 100* 1s lifted from the conveyor 96 and disposed on a ply 102 on the conveyor 97, whereupon a ply 104 from the table 105 is disposed on top of each partial assembly thus formed.

In certain cases, and particularly where different types of wood are used in the face and back plies than in the core, and also where the face and back are so thin that it is undesirable to apply a gluing material directly thereto, it is desirable to apply gluing material directly to both sides of the core. One type of method and means to this end is exemplified in Fig. 19. A series of cores 106 are taken successively from a table 107 and placed on a conveyor 108. They are passed successively by the conveyor through the zone of adhesive material disseminated by a disseminating means 109. Simultaneously a series of back plies 110 are taken from the table 110a and placed on a conveyor 111 which moves parallel to the conveyor 108. After each one of the cores has received a coating on one side, it is picked up and turned over so that its coated surface rests against the upper surface of a pl 110, whereupon the partial assembly thus ormed is passed under a disseminating means 112, whereby the uncoated surface ofthe core is coated. A face ply 113' is then taken from a table 114: and placed upon the partial assembly, this procedure being performed successively in a continuous manner.

In the formation of plywood panels in accordance with the invention the assembled plies are subjected to bonding conditions in any Well known or suitable manner. For example, after the assembly is completed, regardless of the number of plies it contains, the same may be suitably disposed and treated in a suitable press ,or other bonding mecha nism, such mechanism comprising any of the many well known means, or any other suitable means to this end. I

It will thus be seen that there has been provided a method and means whereby the application of gluing materials in discrete partlcle form may be readily accomplished, and whereby the formation of plywood may not only be more effectively and satisfactorily accomplished, but also whereby plywood may be produced in a particularly efiicient and inexpensive manner, and can be produced in large quantities in a relatively small space.

Moreover, there is provided a procedure and apparatus whereby the lack of uniformity resulting from the use of prior procedures in practical quantity production is reduced or avoided, whereby plies of different thicknesses may be glued without interruption in continuity, whereby any likelihood of breakage is eliminated, whereby the spread can be readily varied without discontinuity of operation, and whereby the handling and gluing of the rectangular pieces of precut veneer commonly available to the gluer is greatly simplified and facilitated.

For the sake of facility of expression, the term wooden squares is utilized to describe such pieces of veneer and the like, and it is to be understood that this term, as used in the appended claims, is intended to include plies of natural wood and plies of artificial sheet material used as substitutes therefor, which plies are sufliciently short so that they may e readily handled without rolling or unrolling, regardless of their geometric shape.

Since certain changes in carrying out the above process and in the constructions set forth, which embody the invention may be made without departing from its scope, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended to cover all of the generic and s ecific features of the invention herein descri d, and all statements of the scope of the invention which as a matter of language might be said to fall therebetween.

Reference is hereby made to my co-pending applications Serial Nos. 538,983, filed May 21, 1931, and 596,070, filed March 1, 1932. Reference is also made to the co-pending ap plication of myself, Irving F. Laucks and Charles N. Cone, Serial No. 351,822, filed April 1, 1929.

Having described my invention, what I claim as new and desire to secure by Letters Patent is:

1. The method of assembling plywood panels which comprises passing 1n a continu-= ous manner through a zone in which there is a controlled concentration of the adhesive particles suspended in air the surfaces of plies that are to receive the adhesive, and i ringing such' surfaces into juxtaposition with the remaining plies.

2. The method of forming plywood, which comprises continuously disseminating a powdered adhesive material in air in a given zone, passing wooden squares one after another through said zone to receive said adhesive material on a surface thereof, forming assemblies each including at least one of said coated squares, and subjecting the assemblies to wooden square upon the coated surface of each partial assembly, and subjecting the assemblies to bonding conditions.

4. The method of forming plywood, which comprises continuously disseminating a powdered adhesive material in air in a given zone, continuously disseminating a supplemental material in another zone, passing wooden squares one after another first through one of said zones and then through the other of said zones to receive said materials on a surface thereof, forming assemblies each including at least one of said coated squares, and subjecting the assemblies to bonding conditions.

5. The method of forming plywood, which comprises continuously disseminating a powdered adhesive material in air in a given zone, continuously disseminating a liquid in another zone, passing wooden squares one after another first through one of said zones and then through the other of said zones to receive said materials on a surface thereof, forming assemblies each including at least one of said coated squares, and subjecting the assemblies to bonding conditions.

6. The method of forming plywood, which comprises continuously disseminating a powdered adhesive material in air in a given zone, continuously disseminating a plasticizing liquid in air in another zone, passing relatively dry wooden squares one after another first through one of said zones and then through the other of said zones to receive said materials on a surface thereof, forming assemblies each including at least one of said coated squares, and subjecting the assemblies to bonding conditions.

7. The method of forming plywood, which comprises continuously disseminating a powdered adhesive material in air in a given zone, continuously disseminating a liquid in air in another zone, passing wooden squares one after another first through the first-mentioned zone and then through the second-mentioned zone 'to receive said materials on a surface thereof, forming assemblies each including at least one of said coated squares, and subjecting the assemblies to bonding conditions.

.8. The method of forming plywood, which comprises continuously disseminating a liquid in air in a given zone, continuously disseminating a powdered adhesive material in air in another zone, passing relatively dry wooden squares one after another first through the first-mentioned zone and then through the second-mentioned zone to receive said materials on a surface thereof, forming assemblies each including at least one of saidcoated squares, and subjecting the assemblies to bonding conditions.

9. The method of forming plywood, which comprises continuously disseminating a powdered adhesive material in air in a given zone,

continuously disseminating a liquid in air in another zone, passing wooden squares one after another first through one of said zones and then through the other of said zones to receive said materials on a surface thereof, successively forming partial assemblies each including one of said coated squares and an additional square, continuously disseminating a powdered adhesive material in air in an additional zone, continuously disseminating a liquid in air in another additional zone, passing said partial assemblies first through one of said additional zones and then through the other thereof, completing each assembly, and subjecting the assemblies to bonding conditions.

10. The method of forming plywood, which comprises continuouslydisseminating a powdered adhesive material in a given zone, passing wooden squares one after another through said zone to receive said adhesive material on the surface thereof, similarly causing said wooden squares to receive adhesive materials on their opposite surfaces, forming assemblies each including at least one of said coated squares and at least two additional wooden squares and subjecting the assemblies to bonding conditions.

11. The method of forming plywood, which comprises continuously disseminating a powdered adhesive material in air in a given zone, passing wooden squares one after another through said zone to receive said adhesive material on a surface thereof, moving additional wooden squares alongside the firstmentioned squares, disposing a coated surface of each of the first-mentioned squares upon the upper surface of one of the secondmentioned squares, continuously disseminating a powdered adhesive material in a second zone, passing the previously formed partial assemblies through said second zone with the first-mentioned squares in position to receive said adhesive material on the surfaces thereof opposite the previously coated surfaces, successively completing said assemblies, and subjecting the assemblies to bonding conditions.

12. The method of forming plywood, which comprises continuously projecting a cloud of moist adhesive particles in a given zone, passing commercially dry wooden squares one after another through said zone to receive said adhesive material on a surface thereof, forming assemblies each including at least one of said coated squares, and subjecting the assemblies to bonding conditions. The method of forming plywood, which comprisescontinuously disseminating powdered adhesive material in air in a given zone, continuously directin a cloud of discrete particles of a liquid into the disseminated material to form a cloud of moist particles, passing wooden squares one after another through said zone to receive said adhesive material on the surface thereof, forming assemblies each including at least one of said coated squares, and subjecting the assemblies to bonding conditions.

14. The method of forming plywood, which comprises moving relatively to each other a series of wooden squares and mechanism for disseminating a cloud of powdered adhesive material on a surface thereof, said movement being uniform with respect to I each of said squares, forming assemblies each including at least one of said coated squares, and subjecting the assemblies to bonding conditions.

15. Apparatus for the formation of plywood, including conveyor means adapted to support wooden squares and to carry the same along a path, and means to direct particles of a powdered adhesive material toward'the path of movement of the squares, said directing means being disposed suiticiently above said conveyer means to permit wooden squares of various heights to be moved thereunder.

:16. Apparatus for the formation of plywood, including conveyor means adapted to support wooden squares and to carry the same along a path, means to direct particles of a powdered adhesive material toward the path of movement of the squares, said direct-- wooden squares.

ing. means being disposed sufliciently above said conveyor means to permit wooden squares of various heights to be moved thereunder, and means to vary the relative speed of the conveyor and the action by the directing means to regulate the amount of powdered adhesive material received by the 17. Apparatus for the formation of plywood, including conveyormeans adapted to support wooden squares and to carry the same along a path, means to direct particles of a powdered adhesive material toward the path of movement of the squares, and means to direct particles of a liquid toward the path of movement of the squares, each of said directing means being disposed sufiicientlyabove said conveyor means to permit wooden squares of various heights to be moved thereunder.

18. Apparatus for the formation of plywood, including conveyor means adapted to support Wooden squares and to carry the same along a path, means to direct particles of a powdered adhesive material toward the path of movement of the squares, and means to comingle particles of a liquid with the disseminated powder before the latter reaches said path, said directing and comingling means being disposed sufficiently above said conveyor means to permit wooden squares of various heights to receive said comingled particles.

19. Apparatus for the formation of plywod, including conveyor means adapted to along a path, and means to direct particles of a powdered adhesive material toward a portion of said path, said conveyor means in-' cluding a pair of aligned conveyor elements sufficiently spaced to leave a gap therebetween at the aforesaid portion of said path and sufficiently close together so that the squares will bridge said gap.

20: Apparatus for the formation of plywood, including conveyor means adapted to support wooden squares and to carry the same along a path, means to direct particles of a powdered adhesive material toward a portion of said path, said conveyor means including a pair of aligned conveyor elements sufficiently spaced to leave a gap therebetween at the aforesaid portion of said path and sufliciently close together so that the squares Will bridge said gap, and battle means for preventing the disseminated material from reaching either of said conveyor elements.

21. Apparatus for the formation of plywood, including conveyor means adapted to support wooden squares and to carry the same along a path, means to direct particles of a powdered adhesive material toward the path of movement of the squares, said directing means being disposed sufficiently above said conveyor means to permit Wooden squares of various heights to be moved thereunder, said directing means comprising a vibratory member, and means continuously to supply a controlled flow-of powdered adhesive material to said vibratory member.

In testimony whereof I affix my signature.

THEODORE WILLIAMS DIKE.

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