US2701592A - Machine for joining veneer sheets - Google Patents

Description

Feb. 8, 1955 o. B. NYSTROM MACHINE FOR JOINING VENEER SHEETS Filed 001:. 51 1951 (0 6 7 47 gm, WWQ

United States Patent MACHINE FOR JOINING VENEER SHEETS Olof Birger Nystrom, Sundsbruk, near Sundsvall, Sweden, assignor, by mesne assignments, to Adolf Friz G. m. b. H., Stuttgart-Bad Cannstatt, Germany between a lower pressing device provided with conveyance apparatus and an upper pressing device provided with contact-pressure roll, and the veneer edges to be joined are pressed together.

The tensionally connected joining of the upper with the lower pressing device was performed in the prior machines by means of an arm starting from the side of the machine frame and extending laterally in a curve over at least a part of the veneers to the upper pressing device and which, especially when veneer strips of great width or in great number were to be joined, resulted not only in a considerable increase in prace of the machine and increase of its weight and material requirement, but was also an obstacle in working and when shipping the machine.

This lateral arm, with all its disadvantages, can be eliminated entirely according to the invention in that, for the connection of the upper pressing device with the lower pressing device, a beam is employed which extends in the direction of strip feed and is supported on the frame at a point where the veneer edges to be joined do not yet touch each other.

These and other characteristics of the invention will appear from the following detailed description, in which reference is had to the accompanying figures of the drawing, said figures illustrating diagrammatically an example of one way of embodying a device according to the invention.

Figure 1 shows a side view of a machine arranged in accordance with the invention and intended for the edgewise joining of veneer panels and the like by gluing.

Figures 2, 3 and 4 show cross sections of the machine on the lines 2--2, 3-3 and 44, respectively, of Figure 1.

In the drawing, 2 designates a lower stationary press member, on which an upper movable press member 3 is adapted to rest freely, or substantially freely, with its entire weight. manner, provided with a number of rolls 4, the axes 5 of which (Figure 4) preferably form an angle both with each other and with the direction of feed of the objects to be joined, so that the veneer sheets, on which glue has been applied, will under the influence of the pressure of the press member 3 be pressed against each other in a sideways direction when being moved forward between the press members, for example, by means of conveying members provided on the lower press member. Said conveying members may consist of endless conveying belts or the like 6. For the purpose of drying and hardening the glue in the joint the press members are provided with heating bodies 7, 8 of a known kind. In front of the press members 2, 3 there is a section, comprising means for conveying the veneer sheets to be joined up to and for introducing them between the press members. Furthermore, there are means for guiding, during the said feeding operation, the panels in the desired manner, indicated in the opening paragraph of the specification, and for providing them with glue on the edges or surfaces along which the joining is to take place. Such means will be described more particularly in the following.

The veneer panels to be joined are delivered to the press members over a feed table having a wide horizontal bed 9 adjacent the entrance end of the press, and

The press member 3 is, in a known 4 separate feed table sections 10, 11 for the individual panels; the table sections 10 and 11 being in different planes which merge into the common horizontal feed bed 9. For example, the table section 10 may be in the horizontal plane of the bed 9 throughout its length, whereas the table section 11 may slope downwardly towards the bed 9. The stationary press member 2 is countersunk or grooved to receive the conveyor belts 6; the arrangement preferably being such that the upper surface of the conveyor belts is in horizontal alinement with the surface of the feed table 9 and slightly above the surface of the press member 2. An elongated beam comprising an upper horizontal Web 12 and a vertical supporting web 13, is integral with or secured to the feed table between the sections 10 and 11, and extends in the direction of the feed of the veneer panels. Guide surfaces are provided for the opposed edges of the veneer panels as they are advanced towards the feed table 9, and preferably, as shown in Fig. 2, by grooves 14, 15 which extend along opposite sides of the vertical Web 13 of the longitudinally extending beam. The lower surfaces of the guide grooves 14 and 15 are extensions of the planes of the feed table sections 10 and 11, respectively, and the root surfaces of the grooves are alined in a vertical plane. The beam 12, 13 does not extend along the entire length of the feed table sections 10, 11 and additional guide means such as a fillet or rib 16, Fig. 3, may be provided on the feed table in advance of and/or beyond the beam.

The veneer panels or strips are pressed against the table sections 10 and 11 by idler feed rolls carried by arms 17 pivoted on the web 13 and biased by their weight and/or by springs 18 to press the supporting means 19 of idler rolls 20 towards cooperating driven feed rolls 21.

The upper web 12 of the beam constitutes a support and lateral stabilizer for the elongated bar member 22 which positions the upper press member 3. The bar member is of rectangular strap form at the web 12 and is clamped in a groove to the upper surface of the Web 12 by a hinged plate 23. The forward end of the bar 22 is pivotally connected by a pin 24 to the forward end of the casing 25 of the press member 3 and has a snug sliding fit between parallel flanges 26 which extend upwardly from the casing 25 at the rear end. For rigidity, the bar 22 is preferably of inverted channel cross-section in advance of the strap portion which is clamped to the web 12. The forward end of the press member 3 bears, by gravity and/or the resiliency of the bar 22 upon the veneer panels in transit through the press, and a uniform or a graduated distribution may be obtained by adjustable pressure means located at one or more points between the supporting bar 22 and the casing 25 of the press member 3. The pressure means may be, as shown in Fig. l, a flange 27 on casing 25, and a screw 28 threaded through the bar 22 to bear upon a spring 29 seated on the flange 27.

The glue applying device, which is of a kind known per secomprising a vertical glue collecting roll 31, dipping into a receptacle 30 for the glue, and a slanting glue applying roll 32 in contact with the former roll-is provided adjacent the feed-in rolls 20, 21 where the adjacent edges of the panels to be joined are in vertical alinement with but vertically spaced from each other. Hereby the veneer edge to be coated with glue will be held in a suitable position for the glue to be applied.

It has proved that by means of a device according to the invention very good results will be obtained, particularly when joining veneer panels by means of gluing, because the panels need not be subjected to lateral bending stresses when applying the glue and at the same time a device is obtained that will effectively guide the panels and keep them pressed together during the passage through the drying zone. Furthermore, it is attained that the upper movable press member can be held in position on the lower stationary press member without necessitating the provision of a yoke or an arm extending from the frame of the machine. said yoke or arm limiting the width of operation. Moreover, the press members may be quickly and easily removed for cleaning and so on.

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

1. In a veneer joining machine, a lower press member, a frame including tables for supporting veneer strips to be joined, conveyor means for advancing the veneer strips over said tables and said lower press member, means guiding the veneer strips from initial positions on said tables with their opposed edges in different planes to final positions on said lower press member with their opposed edges in contact, an upper press member for pressing the veneer strips to said lower press member, and means mounted on said frame between said tables for supporting said upper press member; said supporting means extending in the direction of movement of said veneer strips.

2. In a veneer joining machine, the invention as recited in claim 1, wherein said supporting means includes a beam secured to said frame, a bar carried by said beam, and means connecting said upper press member to said bar for angular movement of said upper press member about a horizontal axis.

3. In a veneer joining machine, the invention as recited in claim 2, wherein said connecting means includes means preventing lateral movement of said upper press member with respect to said supporting means.

4. In a veneer joining machine, the invention as recited in claim 1, wherein said supporting means includes a beam secured to said frame, and said guiding means comprises grooves in said beam, the opposed edges of the veneer strips being seated against and guided by the roots of the respective grooves as they are moved over said tables.

5. In a veneer joining machine, the invention as recited in claim 4, wherein the roots of the respective grooves are located in the same vertical plane, whereby the veneer strips are moved Without lateral shifting from their initial positions on said tables to their final positions on said lower press member.

References Cited in the file of this patent UNITED STATES PATENTS 1,010,846 Black Dec. 5, 1911 1,771,105 Williams July 22, 1930 2,196,326 Robinson Apr. 9, 1940 2,269,816 Gustin Jan. 13, 1942 2,351,946 FriZ June 20, 1944 2,516,280 Welch July 25, 1950 2,544,133 Carlson Mar. 6, 1951 2,571,604 Payzant Oct. 16, 1951

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