US2181164A - Veneer bend - Google Patents

Description

Nov. 28, 1939. E. E. ALEXANDER 2,181,164

VENEER BEND Filed Feb. 20, 1939 [010 if JAE-N055 Patented Nov. 28, 1939 UNITED STATES PATENT OFFICE 5 Claims.

This application is a continuation in part of my United States application Serial Number 202,651, filed April 18, 1938.

This invention relates to the formation of bends in wood and particularly in built-up or ply wood of that nature having a core over which one or more plies of veneer are secured.

The primary purpose of this invention is to provide a structure permitting the formation of a bend in such material which will give a perfectly smooth and continuously curved exterior surface and at the same time may be formed without the necessity of having to insert sticks or the like to'complete the inner portion of the bend.

A further object of the invention is to provide an exceedingly simple and relatively cheap means for relieving the backside of that zone which is to be bent in a manner which will permit the formation of a smooth interior surface around the bend. a

These and many other objects and advantages will become apparent to those versed in the art in the following description of the invention as illustrated in the accompanying drawing, in which Fig. 1 is an inside elevation of a length of a panel in flat form;

Fig. 2, an edge view of the panel;

Fig. 3, a similar edge view but showing the panel in the bent position;

Fig. 4, an outside elevation of the bend;

Fig. 5, an edge view of a panel in slightly modifled form; and

Fig. 6, an edge view of the panel as indicated in Fig. 2 in a disassembled relation.

Like characters of reference indicate like parts throughout the several views in the drawing.

A panel is formed in the usual manner to have a body or core I!) on the outside of which is glued one or more plies of veneer wood I I, herein shown as two in number. The inside of the panel is preferably provided with one or more plies of veneer glued to the core Ill, these plies being designated by the numeral I2 and shown as being two in number. The panel is formed fiat and the core I0 is cut away from the backside and a ply of veneer I3 is glued directly against the outer plies II. On top of this added ply I3 is placed a second ply of veneer I4.- The ends only of this second ply I4 are glued to the ply I3. Then on top of the ply I4 is placed a block I5 to fill out the balance of the thickness of the core I0 and this block is glued over its entire underside to the ply II. Over the block I5, and preferably extending somewhat therebeyond, are placed one or more plies of veneer I6 to complete the building up of this bend zone to the thickness of the balance of the panel.

The outer plies I6 have their grain turned to be transversely directed across the panel rather than longitudinally thereof. Then a number of spaced apart cuts H in the nature of slots are made through the plies I6 and through-the block I5 down to the ply of veneer I4. The shape of these cuts I1 may vary, but, in the form shown, are narrow V-slots of such width and in such number that when the bend is made these slots will be completely closed and glue placed therein to cause one side of each slot to be held in close intimate contact with the other side. A further out I8 is made at one end of the block I5 by cutting entirely through the plies IS, the block I5, and the ply I4. This cut is made sufliciently wide, as indicated in Fig. 2, as will permit the rolling up of the block I5 as indicated by the dash lines, it being remembered that this top ply I4 is not glued to the under my I3 throughout its major length.

The panel is then bent to give the desired curve, here shown as a ninety degree curve, Fig. 3, whereupon .the block I5 will be carried around, as indicated, to close the slots therein and to cause the end cut to be completely closed by relative longitudinal travel between the block I5 and its veneer ply I3 over the veneer ply I4 and the outer veneer plies II. This end cut,'as indicated, must be so proportioned that this travel will cause the end of the block I5 to come into abutment with the opposing stationary end that is securely glued in position. Prior to bending, the central block I5 is lifted as indicated by the dash lines, and a film of glue is placed thereunder. Also glue is placed in the various slots and across the faces of the end cut. Following the bending of the panel, the bend is held in any suitable manner until this glue sets or dries so that the bend will become permanent through the holding action of the glue.

It is to be noted that the veneer ply I4 which is glued to the block I5 securely ties together the individual blocks formed by the slots I'I. Alsoit is to be noted that by placing the inner plies of veneer It to have their grain extend transversely across the panel, the veneer remaining on the inside surfaces of the individual blocks between the slots will not tend to chip oil? while these slots are being cut nor will they tend to separate there after.

As a modified form, it is possible, as indicated in Fig. 5, to formthe core I5 without gluing its back to the under veneer I4, the initially loose ply. It being omitted in this form, and two plies I3 being used and glued to the outer plies II. In this case, the block 15 is not cut entirely therethrough by the slots I! so that the uncut portion will serve as means to tie together the portions of the block between cuts,

In any event, the veneer plies l3 and I4 are preferably made out of relatively soft wood so that when the bend is formed, the portions of the block l5 along the fold lines back of the slots'll may embed themselves in these plies of soft wood instead of carrying those lines out in visible form through the outer plies ll. Of course, the closer the slots H are placed, the less width there is between the slots around the bend adjacent the plies l3 and hence the less tendency there is for lines of folding of the block to show" through the outer veneer plies when the bend is completed.

While I have herein shown my invention in the best form as now known to me, it is entirely obvious that structural changes may be made without departing from the spirit of the invention and I, therefore, do not desire to be limited to that precise form beyond the limitations as may be imposed by the following claims.

I claim:

1. For a ply wood bend, a panel having a core, an outer veneer ply adhering thereto, an added ply of veneer behind said outer ply extending at least over the zone of the bend, said core being provided with a plurality of relatively closely spaced slots extending transversely across the panel back of said added ply, that part of the core which is out being free to travel longitudinally of the panel relative to said outer ply and having an end portion removed equal to said travel.

2. For a ply wood bend, a panel having a core,

an outer veneer ply adhering thereto, an added ply of veneer behind said outer ply extending at least over the zone of the bend, said core being provided with aplurality of relatively closely spaced slotsextending transversely across the panel back of said added ply, that part of the core which is cut being free to travel longitudinally of the panel relative to said outer ply and having'an end portion removed equal to said,

travel, said added ply being sufficiently soft to permit embedding therein of bends of said out portion of the core occurring under said slots.

3. For a ply wood bend, a panel having a core, an outer veneer ply adhering thereto, a second ply of veneer behind said outer ply extending at least over the zone of the bend, 'said core being provided with a plurality of relatively closely spaced slots extending transversely across the ipanel back of said second ply, that part of the \core which is out being free to travel longitudinally of the panel relative to said outer ply and having an end portion removed equal to said travel, said slotted core portion having its back glued to said second veneer ply, and said second ply being anchored at one end and free to shift over the outer ply with said core portion.

4. For a ply wood bend, a panel having a core, an outer veneer ply adhering thereto, a second ply of veneer behind said outer ply extending at least over the zone of the bend, said core being provided with a plurality of relatively closely spaced slots extending transversely across the panel back of said second ply, that part of the core which is out being free to travel longitudinally of the panel relative to said outer ply and having an end portion removed equal to said travel, said slotted core portion having its back glued to said second veneer ply, and said second ply being anchored at one end and free to shift over the outer ply with said core portion, said slots extending entirely through said core portion to said second ply.

5. For a ply wood bend, a panel having a core, an outer veneer ply adhering thereto, a second ply of veneer behind said outer ply extending at least over the zone of the bend, said core being provided with a plurality of relatively closely spaced slots extending transversely across the panel back of said second ply, that part of the core which is out being free to travel longitudinally of the panel relative to said outer ply and having an end portion removed equal to said travel, said slottedcore portion having its back glued to said second veneer ply, and said second ply being anchored at one end and free to shift over the outer ply with said core portion, said slots extending entirely through said core portion to said second ply, that part of the corecarrying said slots consisting of a separate filler block.

ELMO E. ALEXANDER.

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