A SOLID GLUED BOARD PRESS

Abstract: The object of the invention is a solid glued board press, in particular a blockboard press, which includes a glue handling device, two or more glue nozzle (8), a glue distribution device, wood strip transportation devices to move a wood strip past the nozzles (8), and a press section. A press in accordance with the invention includes at least two glue nozzles (8) which are located in essentially the gluing level that corresponds to the surface of the wood strip (9), in such a way that when the glue nozzles (8) are turned round an axis that is vertical to the gluing surface the width of gluing can be varied, and that the glue nozzles (8) include shut-off devices (7), which are arranged in such a way that when the wood strip (9) presses the shut-off device (7) it opens the glue nozzle (8), when the glue flows onto the surface of the wood strip (9). The operation of a gluing head is improved by means of the invention.

Description: A Solid Glued Board Press The object of the invention is a solid glued board press, in particular a blockboard press, which includes a glue handling device, two or more glue nozzles, a glue distribution device, strip handling devices to transport the wood strips past the nozzles, and a press section. Various kinds of continuously operating blockboard presses are known. These are typically continuously operating in such a way that wood strips of a particular size are fed to the press as a continual flow at the same time as glue is fed from a nozzle to one vertical surface of the strip. The press includes sensor devices that open the glue channel when a wood strip comes close to the glue nozzle. The glue channel closes when the wood strip leaves the area of influence of another sensor device. After this the strip is taken to a press, in which the strips are placed one after the other to correspond to the desired size of sheet. A problem with the known gluing presses is the poor controllability of the glue and due to this the unreliability of gluing devices and the difficulty of adjusting the width of the gluing. In several known gluing presses a glue nozzle of a standard size, in which case glue has spilled over narrow wood strips to a considerable extent. The excess glue can even cause distur¬ bances in operation and at the very least additional cleaning. The intention of this invention is to create a solid glued board press, by means of which the aforementioned defects can be avoided. The invention is especially intended to improve the operation of the gluing head. The principal characteristic features of the invention appear in Patent Claim 1. In a gluing press in accordance with the invention the glue is fed precisely over the whole length and breadth of the wood strip. The nozzles are, however, closed between the strips and the operation is thus considerably cleaner than previously. In order to control several glue nozzles it is advantageous to form e acc ce with Patent Claim 2. Other advanta- geous forms of application are shown in connection with the latter example of application. In what follows the invention is illustrated by reference to the accompanying figures which show one kind of glued board press gluing head in accordance with the invention, and its operation. Figure 1 shows the gluing head seen from above Figure 2 shows the gluing head seen from the side The glued board press consists of wood strip handling devices, a gluing head, and the press itself. The accompanying figures only show the wood strip handling devices at the gluing head and the gluing head itself. The wood strip handling devices move one strip at a time past the gluing head 1 with the aid of a guide plate 19 and counter- wheel 10. By means of these the wood strip pushes in the ball valves of the nozzles 8 of the gluing head, when the glue extrudes onto the surface of the wood strip. As the wood strip passes the gluing head the balls 7 return to the extreme position by means of the pressure and springs 15 and close the nozzles 8. The glue distribution device includes a glue reservoir 20, a pump 12, a return circulation channel and its pressure valve 16, operating valve 11 and the glue channel 21 that leads from it to the nozzles 8. In the gluing,head 1 the glue is distribu¬ ted to each nozzle 8 through separate restriction valves 13. By means of these the flow of the glue is suitably regulated. In certain cases a greater flow is wished for in the upper nozzle than in the lower. The device also includes normal sensor components, by means of which it is known when the wood strip is close to the gluing head, on the basis of which the control valve 11 is switched to the feed position. The gluing nozzles 8 open only when the wood strip pushes the ball of the shut-off device 7 inwards. When the wood strip has passed each nozzle the spring in it pushes the ball shut and the nozzle 8 closes. As long as the nozzles 8 are closed, the pump 12 pushes the glue flow through the pressure valve 16 to the glue reservoir 20. Figure 2 shows the principle of the control of the width of the gluing. Wood strips of different widths 9, 14 can be glued by the same gluing head by adjusting its angle. The line formed by the gluing nozzles 8 is turned in such a way that its width corresponds to that of the wood strip. The figure shows the gluing head and the position of the gluing nozzles 8 for two different widths of strip. The width adjustment is stepless from the minimum wood strip width up to the maximum strip width. The adjustment of the angle * takes place by loosening the head- wheel 6 and by turning the gluing head 1 round the axle pin 17 then locking the gluing head into the new position by means of the handwheel 6. Height adjustment takes place by turning handwheel 3, when the entire gluing head moves vertically along guide 4. The entire gluing head can be removed from the gluing level by means of operating device 5, which is advantageously a pneumatic cylinder. This kind of removal is necessary for example when a so-called dry joint is required to separate sheets of wood strip from one another.

Claims: Patent Claims 1. A solid glued board press, in particular a blockboard press, which includes a glue handling device, two or more glue nozzles (8) , a glue distribution device, wood strip handling devices to transport a wood strip past the nozzles (8) and a press section, characterized in that the press includes at least glue nozzles (8) which are located in essentially the same line at a gluing level corresponding to the surface of the wood strip (9) in such a way that when the gluing nozzles (8) are turned around an axis vertical to the gluing level the gluing width can be altered, and that the gluing nozzle (8) includes shut-off devices (7) , which are arranged in such a way that when the wood strip (9) presses against the shut-off device (7) it opens the glue nozzle (8) , when the glue flows onto the surface of the wood strip (9) . 2. A solid glued board press in accordance with Patent Claim 1, characterized in that the glue nozzles (8) are located in a separate gluing head (1) and that the glue distribution device includes a glue reservoir (20) , a pump (12) , a control valve (11) and glue channels (21) to lead the glue to the glue nozzles (8) and that each glue nozzle has its own flow restric- tor (13) . 3. A solid glued board press in accordance with Patent Claims 1 or 2 characterized in that it includes a wood strip guide (19) located at essentially the level of the gluing surface, which extends on either side of the glue nozzle (8) and which press includes a counter wheel (10) located on the opposite side to the glue nozzles (8) , which forces the wood strip to move against the points of the glue nozzles (8) . 4. A solid glued board press in accordance with one of Patent Claims 1 - 3, characterized in that the aforementioned shut-off device (7) is formed by a spring- loaded ball valve, in which the ball that closes the glue nozzle (8) is arranged to protrude slightly from the point of the glue nozzle (8) in such a way that when it is pressed it opens the channel of the nozzle (8). 5. A solid glued board press in accordance with one of Patent Claims 1 - 4, characterized in that the press includes an operating device (5) to move the nozzles (8) to the gluing surface and a distance away from it.

Inventors: AUTIO TAISTO, AUTIO, TAISTO
Applicants: AT INNOVA OY, AT-INNOVA OY
Application year: 1990
Main classification: B05C5
IPC codes: B05C5, B27G11