FI96409B - Method and arrangement for unstacking stacks of timber - Google Patents

Description

96409

The present invention relates to a method according to claim 1 and to an apparatus according to claim 2 for unpacking a timber package.

Current timber leveling and sorting plants almost invariably have an arrangement for unloading a ribbed package, in which the ribbed timber package is tilted at an angle of about 45 ° and the package is lifted from the bottom by gravity, always removing one layer of timber at a time over a fixed edge. The timber itself is directed to the collection conveyor using roller beams or sliding surfaces, and the intermediate strips fall from the above to their own conveyor, from where they are usually taken to a stripping plant for reuse. With current methods, full-edged and especially pak-15 su plank goods are unloaded into a beautiful carpet on a collection conveyor, which in turn feeds the goods to overflow rollers and the pocket of the curtain.

Often, especially in more efficient facilities, there are even two curatories in a row. The kiramo is actually only needed for the luggage, which usually comes packed in a miscellaneous pile when it arrives at the collector. For the purpose of clearing this pile, chimneys are usually used, especially when the bulk of the normal sawmill's production is piece goods.

Even in Finland, you can still find old plants where the unloading takes place without the help of Kira-25. These facilities are being dismantled because the transportation of the cargoes is rubbish, laa. Kiramos per se are suitable devices for separating timber, but they also have a few disadvantages: dry timber dusts in the pocket of the kiramo and an even worse disadvantage is the breakage of the timber in the kiramo.

30 A precious full-edged grouse loses some of its edges in the curtain and the board can even break or crack in rough use of the curtain.

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The object of the invention is to provide a method and apparatus for unloading a package of sawn timber, by means of which the disadvantages of the sawmills can be avoided and by which a reliable and noise-free unloading operation is achieved.

The method according to the invention is characterized by what is stated in the characterizing part of claim 1.

2 96409

The device according to the invention, in turn, is characterized by what is stated in the characterizing part of claim 2.

The solution according to the invention makes it possible to transfer the layer 5 in the timber package as a carpet to the collection conveyor and from there one by one to the straight line without a rotor.

Since the speed of the collection conveyor is the same as the speed of the timber coming to it, the pieces of timber do not tend to move relative to each other and form 10 piles. Reliable operation is ensured by a conveyor that weighs timber pieces from above. However, when driving thick goods, an overhead conveyor is not required.

The invention will now be described in more detail with reference to the accompanying drawing, which shows a schematic side view of an embodiment of a device according to the invention.

The timber unloading device shown in the drawing comprises an elevator device 1 with a timber package 2 inclined at an angle of about 45 °. The timber package is formed of overlapping layers of timber 3, between which ribs 4 are arranged transversely to the longitudinal direction of the pieces of timber 5. One layer of timber is removed from the package by gravity at a time by lifting it over the upper edge of the frame 6 supporting the back side of the package. The timber is guided by means of a roller track consisting of rollers 7 to a collection conveyor 8. The slats fall on their own conveyor (not shown) and are taken to a stripping plant for reuse.

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The collection conveyor comprises a lower conveyor comprising a plurality of chains or belts 9 supporting parallel pieces of timber, and an upper conveyor with parallel belts 10 weighing the pieces of timber from above.

The upper conveyor comprises a body 11 supporting a plurality of pulleys, two of which 12 and 13 are attached to pivotally mounted arms 14 and 15 which are connected to each other so that the rollers 12 and 13 move in the same way. The pulleys with their belts can “” turn to the side, changing the distance between the belts 9 and 10. Attached to the arm 14 is a rod 16 having an ester ring 17 at its end which, together with a stop plate 18 attached to the body 35, forms a limited position for the lower position of the roll 12. Between the arm 14 and the abutment plate 18 there is a spring 19 which provides a force which flexibly compresses the timber pieces 5 between the belts 9 and 10 and allows the belts 9 to move up and down as the thickness of the timber pieces changes. By means of the air cylinder 20 acting on the arm 15, the pulleys with their belts can be turned up, 3 96409 so that the belts 9 do not touch the pieces of timber on the lower conveyor at all, e.g. when driving thick goods or in case of disturbances.

The chains 10 support two sprockets 21 and 22, so that a substantially horizontal part of the chain conveyor supporting the timber mat is formed. One of the sprockets, 22, is connected to a drive (not shown). By means of the chain 23, one of the pulleys, 24 of the upper belt, is connected to the same drive.

The upper conveyor body also has a pivotally mounted arm 25, at the end of which there is a impulse wheel 26 which contacts the surface of the top layer of the timber package.

The impulse wheel measures the speed of the layer of timber removed from the package and the measured value is utilized in a control device 27 suitably connected to the drive of the conveyor.

15 The discharge device shown in the drawing operates as follows. The timber layer 3 detached from the inclined timber package 2 starts the impulse wheel 26, on the basis of the signals of which the control device 27 controls the drive of the collection conveyor 8 so that the speed of the belts 9 and chains 10 corresponds to the speed of the timber. The photocell device 28, which identifies the first-20 or alternatively last board in the timber mat, detects when the entire timber-layer 3 has moved to a straight part of the collectors conveyor chains 10. When the entire layer of timber has moved to the collection conveyor, the speed of the conveyor 8 is slowed down so that it feeds the timber pieces 5 one by one at a speed suitable for each width to the next conveyor. This conveyor consists of helical rollers 29, 25 which move the pieces of timber against a longitudinally rotating end stop 30 while feeding them forward in their transverse direction. The purpose of the longitudinal transfer is to »align the ends of the pieces of sawn timber for the subsequent processing of the timber.

30 Because the pieces of timber are located between two conveyors, they cannot easily move when the speed of the cross conveyor slows down or the conveyor *. completely stopped and restarted for dosing. However, care must be taken to dampen the brakes so that high inertia forces are not generated, especially when driving thick goods without over-compression.

The invention is not limited to the embodiments shown in the figures, but many modifications are possible within the scope of the inventive idea defined by the following claims.

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Claims (6)

A method for unpacking a timber package, in which one timber layer (3) is transferred from a tilted timber package (2) at a time by gravity to a free fall on a collector conveyor (8), characterized in that the collector conveyor (8) is controlled so that its speed when receiving the timber layer is the same as the speed of the incoming timber layer (3); the position of the timber layer (3) is detected by the collection conveyor (8) and when the entire timber layer is detected transferred to the collection conveyor, the speed of the collection conveyor is slowly reduced and the deceleration is stopped at the latest when the timber collection reaches the output of the collection conveyor (22). An apparatus for unpacking a timber package, the apparatus comprising an elevator device (1) from the tilted timber package (2) one layer of timber (3) is removed by free fall by gravity at a time and a collection conveyor (8) receiving the layer of timber 15, characterized in that it comprises devices (26) , 27) for controlling the collection conveyor (8) so that its speed at the time of reception is the same as the speed of the incoming timber layer (3), means (28) for detecting the position of the timber layer (3) on the collection conveyor (8) and decelerating the collection conveyor speed when the entire timber layer has moved the collection conveyor-20 le and to stop deceleration at the latest when the timber layer reaches the output end (22) of the collection conveyor. Device according to claim 2, characterized in that the collection conveyor (8) comprises conveyor chains or belts (10) supporting the timber pieces (5) and conveyor belts (9) supporting the wood spare parts from above. Device according to Claim 3, characterized in that the upper and lower conveyor belts or chains (9, 10) have a common drive device. 4 96409 Device according to Claim 3 or 4, characterized in that the upper conveyor belts (9) are arranged to rise and fall in the up and down directions according to the thickness of the timber pieces (5). Device according to claim 2, characterized in that it comprises means (26) for detecting the speed of the timber layer (3) detached from the timber package (2). 5 96409