SE526793C2 - Machine and method for dividing timber bodies - Google Patents

Abstract

A machine 1 for cutting curved timber 2 into pieces 9,10,11, with the machine having a feed device 3 and a sawing station 4. Timber is fed into the feeding device, and the feeding device feeds the timber in an axial direction into the sawing station. The sawing station is positioned downstream of the feeding device relative to the feed direction of the timber. The machine has at least three band saws 6 and at least four support rollers 12, 12'. The support rollers are remote from the feeding device and the support rollers are each individually adjustable transversally relative to the feed direction of the timber. The support rollers are grouped into pairs, with each pair being axially separated and cooperating with at least one saw band.

Description

00 0 000 0 0 OO 00 0 0 000 000 0000 IOOO 00 CO 0 00 0000 00 0 0 0 0 0 0 0 0 0 0 000 000 0 0 0 0 0 0 00 00 000 10 15 20 25 30 35 526 793: mg The 2 pieces of wood risk having dimensions that do not fall within the predetermined limits.

Most of the logs that pass and are processed in a sawmill undergo a number of operations before the core part of the log is finally divided, into a number of planks or boards, for example by band sawing in a dividing machine terminating in the saw line. In order to obtain a good yield from the raw material, it is recommended that the core part of the log, also known as a four-sided block, be curved in this final operation due to the fact that logs are generally more or less crooked (not infrequently the logs have a radius of curvature in the range 50-100 m , which means that the bow arrow height for, for example, a 4 m long log is in the range 20-40 mm). Curve sawing means that during the dividing operation the block is fed along a curve path which corresponds to the inherent curvature of the block.

Such saw stations generally comprise three or four band saws with one saw band each. The wood body is divided into smaller pieces of wood by the saw bands when it is fed into the saw station. In the case where the saw station includes four band saws, it generates from the four-sided block five smaller pieces of wood, more specifically two outer pieces, two inner pieces and a middle piece. The saw bands are oriented parallel to the feed direction and as a result of the construction of conventional band saws, the saw bands are arranged in pairs, which are axially separated. The saw bands are also arranged in such a way that the saw bands which separate the outer pieces from the timber body are placed in a first pair, and downstream of these the saw bands which separate the inner pieces from the middle piece form a second pair. The second pair of saw bands can also be replaced by only one saw band, which, if applicable, splits the inner pieces apart.

In dividing machines according to prior art, the possibly curved timber body is controlled by means of, for example, four pairs of vertical rollers, arranged in a feed mill which is located upstream of the saw station itself. The rollers are set against two vertical, opposite sides of the timber body oo 0 ooo 00: oooo 000 IO 00 oo oooo 00 oo 9 000 0 o oo loo 10 15 20 25 30 35 o oo oooo oo oo ooooooo I ooov I o 0 oo oooo o O ooooooooooooooooo oo oo 00 oi 526 793 3 while this is longitudinally fed along the saw line. Furthermore, the rollers of the feeder are placed in two rows, which are aligned parallel to the saw line and which can only move simultaneously at an angle thereto. This causes the abutment of the feeder to the timber body to be overdetermined, which causes unnecessary tension in both the timber body and the feeder. In addition, the last pair of rollers in the feed mill, located closest to the saw station, are still attached to the timber body at a relatively large axial distance from the other pair of saw bands. A disadvantage of this troublesome distance is that the same means that the inherent curvature of the timber body contributes to the timber body being able to deviate between the feeder and the saw belts, and thus the precision risks becoming substandard.

In an attempt to overcome this steering problem, the feed unit has been extended in the axial direction forward, more specifically in such a way that the last pair of rollers has been moved forward and placed in the space between the first and second pairs of saw bands. As a result of this change, better control was obtained, but at the same time a disadvantage was added.

More specifically, the advanced rollers risk squeezing the first pair of saw bands between the outer pieces and the remaining part of the timber body, which can damage both the saw bands and the sawn timber. Similar to the above technique, the remaining part of the timber body can deviate from the intended web because that part still lacks control.

OBJECTS AND FEATURES OF THE INVENTION The present invention aims to obviate the above-mentioned disadvantages of previously known dividing machines, and to create an improved dividing machine. A primary object of the invention is to create a dividing machine which provides good control of the timber body during an entire dividing operation.

It is also an object of the invention to create a dividing machine which separates from a timber body smaller pieces of timber with small dimensional variations within each individual dimension class, as well as along each individual 10 15 20 25 30 35 5 2 6 7 9 3 - - zï-z 4 piece of wood. A further object of the invention is to create a dividing machine in which the control of the timber body during the dividing operation is not overdetermined. Another object of the invention is to create a dividing machine in which the control of the timber body during the dividing operation does not take place in the feeder.

According to the invention, at least the primary object is achieved by means of the initially defined dividing machine, which is characterized in that it comprises at least four support rollers removed from the feeder, which are individually adjustably movable transversely to the feeding direction, and arranged in pairs which are axially spaced apart and for arranged to cooperate with at least one saw band, by being attachable to the timber body along a relatively transverse feed direction, an imaginary geometric reference line located in the area of the cooperating saw band. Advantageous embodiments of the machine according to the invention are further apparent from the dependent claims 2-4, as well as from the following, detailed description.

In a second aspect, the invention also relates to a method for dividing any curved wood bodies into a number of smaller pieces of wood. The method is defined by the features set forth in the independent claim 5.

Advantageous methods of carrying out the method according to the invention are further stated in the dependent claims 6-7.

Brief description of the accompanying drawings In the drawings: Fig. 1 is a partially cut, schematic plan view of a dividing machine according to the invention, Fig. 2 a perspective view of a band saw included in the dividing machine, Fig. 3 a perspective view of two band saws mounted in the dividing machine mounted on a stand, and Fig. 4 is a schematic plan view of a dividing machine according to the prior art.

Detailed Description of a Preferred Embodiment of the Invention I Fig. 1 shows a dividing machine 1 according to the invention, which usually forms part of a saw line included in a sawmill or a sawmill.

Before describing the dividing machine 1 in detail, reference is made to Fig. 4, which shows a dividing machine according to the prior art.

Such a machine 1, for dividing a possibly curved timber body 2 into a number of smaller pieces of timber, is usually arranged to perform a final dividing operation in a saw line. Before the timber body 2 when this machine has the same has thus passed and been processed in many stations (not shown). Simplified, this means that a round log is fed into the feed end of the saw line, whereupon the log's shape and curvature are determined, in order to be able to obtain maximum yield from the log. In practice, logs can be crooked in several planes. However, the crookedness is often particularly marked in a main plane. Along the first half of the saw line, a number of edge boards and / or side boards and a cross-sectional rectangular core part, or a so-called four-sided block, shaped. The timber body can thus, after several operations, be likened to a web with a rectangular cross-section, oriented lying on its side in Figures 1 and 4. It should be pointed out that the curvature of the timber body 2 in Figures 1 and 4 is somewhat exaggerated for the sake of clarity. In a finishing machine, this block is divided, or split, into individual planks or boards, which leave the saw line at its discharge end.

It should be pointed out that different types of longitudinal conveyors, such as chain conveyors, extend between the different stations in the saw line, which, however, are not reported in detail.

The dividing machine 1 comprises a feeder 3 and a sawing station 4, which is arranged downstream of the feeder in the feeding direction of the timber body 2. The feeder 3 comprises a chassis 19 and a plurality of rollers or rollers 5, which are rotatable about vertical geometric axes.

Furthermore, the rollers 5 are attachable to the wood body 2 and feed the same in the axial direction into the sawing station 4, as a result of a power source, for example an electric motor (not shown), causing the rollers 5 to rotate. The sawing station 3 comprises a plurality of band saws 6, usually four, which are individually adjustably movable transversely to the feed direction and arranged in axial direction in pairs with a band saw 6 to the left of the saw line and one to the right. 7 carried an endless saw band 8, 8 ', which has a tooth turn in the upstream direction, viewed in the feed direction of the timber body 2. Furthermore, the saw bands 8 are parallel to each other and to the feed direction and in addition axially separated, due to the mutual positioning of the band saws. When sawing, a first pair of saw bands 8 separates two outer pieces 9 from the wood body 2, and a second pair of saw bands 8 'two inner pieces 10 from a remaining middle piece 11. Due to the fact that the band saws 6, and thus also the saw bands 8, 8 ', are movable transversely to the feeding direction, one or more saw bands can be caused to move laterally away from the saw line. In other words, the number of active saw bands 8, 8 'and their location can be changed and in this way different wood bodies 2 can be divided into a varying number of pieces of wood, which have different dimensions. For example, the second pair of saw bands 8 'can be replaced by a single one and then the two inner pieces 10 are split from each other without a middle piece 11 being formed. As far as the dividing machine shown in Figure 4 has hitherto been described, it is substantially previously known and conventional.

Reference is now made again to Figure 1. The dividing machine 1 according to the invention comprises a first pair of vertical support rollers 12 and a second pair of vertical support rollers 12 '.

The two support roller pairs 12, 12 'are axially spaced from the feed unit 3, and also mutually axially separated. Each individual support roller is individually adjustably movable transversely to the feeding direction, in order to reliably position the wood body 2 together during a division 000 OO gg 00 10 15 zoi 25 30 35 526 793 7 operation. Furthermore, the support roller pairs 12, 12 'are each arranged to cooperate with the first pair of saw bands 8 and the second pair of saw bands 8', respectively. More specifically, the support roller pairs are attachable to the timber body 2 along two imaginary geometric reference lines R and R 'transverse to the feed direction, which are axially located in the area of the respective cooperating saw band pairs 8, 8'.

Preferably, said reference lines R, R 'are located upstream of the respective cooperating saw belts. The axial distance between the reference lines R and R 'is about 300 millimeters, and in practice the axial distance between a reference line and the cooperating saw band is 30-40 millimeters.

The support roller pair 12, 12 'controls the timber body 2 during the splitting operation and the feeder 3 is adjustable between an active state, in which the same feeds and guides the timber body 2 into the saw station 4, and a disengaged state, in which the chassis 3 of the feeder 3 compulsively follows the curvature of the timber body 2. In other words, the base 19 of the feeder 3 becomes "free-floating" laterally and in an angular position when the timber body 2 is fed into the sawing station 4 while all four support rollers 12, 12 'are still attached to the timber body 2. The purpose of the feeder 3 is floating is that the positioning of the timber body 2 should not be overdetermined when the support rollers are also engaged against the timber body. However, the feeder 3 continues to axially feed the timber body 2 through the saw station. In an alternative embodiment, however, the feeding can be performed by one or more of the support rollers 12, 12 ', whereby the feeding unit can be completely stopped.

The support rollers 12, 12 'are adjustably movable by being connected in an advantageous embodiment to the carrier 7 of the band saws 6, more specifically, each individual support roller is rotatably mounted in a holder 13, which in turn is mounted on a guide system 14, which is connected with the wearer 7.

Instead of a guide system 14, a slide, a piston-cylinder mechanism, or the like can also be used. The support rollers 12, UI OOIO I. OO UI I o c o 0 0 a o o ica n so. 0000 acc o n o u o o o o o o I OO OI ICC CO OI Ö- C000 GCI 0 I O 10 15 20 25 30 35 526 793 8 in the first pair, are arranged on the same side of the saw band 8 as their associated guide system 14 are located.

The support rollers 12 'in the second pair of support rollers, on the other hand, are arranged in such a way that the guide system 14 extends from the carrier 7 and through the area or plane which is circumferentially surrounded by the saw band 8' carried by the carrier 7, so that the support rollers 12 ' can be applied to the wood body 2 upstream of the saw bands 8 '. Furthermore, the radii of the support rollers 12, 12 'are greater than the axial distance between the saw bands 8, 8' and the respective reference line R, R ', which means that the saw bands and the support rollers cannot be displaced past each other without colliding. However, due to the fact that the support rollers 12, 12 'are connected to the carriers 7, the risk of collision between the support rollers 12, 12' and the saw belts 8, 8 'can be completely eliminated, by providing a maximum stroke for the guide systems 14, which is less than the distance between the carrier and the saw band.

Reference is now also made to Figures 2 and 3. As mentioned above, the individual band saw 6 is in its entirety movably arranged laterally, by being displaceable back and forth in a frame 15, which extends transversely to the feeding direction.

More specifically, the band saws 6 are displaceable between an outer position, in which a timber body 2 can pass freely through the sawing station 4, and an inner position, in which at least one saw band 8, 8 'reaches or past the center of the timber body 2. In the example shown in Figure 3, each band saw 6 has a displaceability of approximately 400 millimeters. It should be pointed out, however, that depending on the application and saw line, the displaceability of the band saws 6 can vary greatly.

At a first, lower end of the carrier or column 7 of the band saw 6, a wheel 16 is arranged on a drive shaft (not shown), and at a second, upper end a wheel 17 is rotatably arranged relative thereto. The vertical spreading planes of the two wheels 16, 17 are flush with each other so that a saw band can run around their peripheries. Furthermore, the drive wheel 16 and the wheel 17 in the plane of propagation are forced in OO OIII OI Oil) OO II Ü Û II Ü 0 0 ICO OQO GCI to OO 0 IIO 0 O lg gg: Jo OI 00 10 15 20 25 30 35 526 795 gg 9 direction from each other, to stretch and tension the saw band so that the same is caused by friction when the drive wheel 16 rotates. At a level above the area where the wood body 2 is sawn, an element 18 limiting each sawing belt is arranged. The limiting element or blade guide 18 is arranged on the carrier 7 and acts against the saw band 8 '. More specifically, the task of the limiting element 18 is to restrict the freedom of movement of the saw band 8 'across the direction of movement of the saw band and thereby ensure that the saw band does not bend in any direction during the splitting operation. In practice, an analogous limiting element (not shown) can be arranged at a level below the area where the wood body 2 is sawn, in order to provide further better control of the saw band.

Due to the function and location of the double support roller pairs 12, 12 'in the sawing station 4, in combination with reassuring positioning of the saw belts, an increased precision can be obtained during a splitting operation. In an advantageous method, the first pair of saw bands 8 is arranged to separate the middle piece 11 from the wood body 2 and the second pair of saw bands 8 ', which is axially spaced from the first pair in the downstream direction, is arranged to separate the outer pieces 9 from the inner pieces 10. This configuration that when the wood body 2 reaches the second pair of saw bands 8 'there is no saw groove between the support rollers 12' and the saw bands 8 ', which inevitably means that the outer pieces 9 and thus the inner pieces 10 have exact dimensions.

Downstream of the sawing station 4, a transverse, horizontal roller (not shown) is arranged, which during a dividing operation can be applied to the upper side of the partially separated pieces of wood. The basic task of said roller is to press the pieces of wood down against the conveyor. It has been found that this roller also has an effect which causes the partially separated pieces of wood to diverge. In other words, the pieces of wood are caused to move in a diverging movement downstream of the support rollers 12 '. This means that when the inner pieces 10 and the outer pieces 9 are to be separated according to 00 II 00 000 000 1000 0 0 0 0 0 00 00 00 00 00 00 00 00 00 00 00 00: 00 good contact between the second pair of support rollers 12 'and the timber body 2. The second pair of support rollers 12' can, partly due to the diverging movements of the pieces of wood, also be applied to the timber body downstream of the saw bands 8 'tooth, without significant risk of the saw bands pinch during the splitting operation.

Advantages of the invention A basic advantage of the dividing machine according to the invention is that it, due to the adjustably movable support rollers and their location, provides good control of the timber body during a complete dividing operation. Another advantage of the dividing machine according to the invention is that thanks to the support rollers the first pair of saw bands can saw the inner saw grooves while the second pair of saw bands saw the outer saw grooves, which gives little or no dimensional variations due to the support rollers guiding the timber body during the splitting operation. Consequently, pieces of wood with small dimensional variations are obtained within each individual dimension class, as well as along each individual piece of wood, which yields maximum financial compensation. It is also an advantage that the feeder is floating during larger parts of the dividing operation, which means that the positioning of the timber body is not overdetermined and no unnecessary stresses in the timber or saw bands occur.

Possible modifications of the invention The invention is not limited only to the embodiments described above and shown in the drawings. Thus, both the dividing machine and the method can be modified in all sorts of ways within the scope of the appended claims. For example, the feeder does not necessarily comprise three pairs of vertical rollers but may advantageously comprise only two pairs. Furthermore, the support rollers do not have to be connected to the carriers of the band saws, but can instead be mounted on individual frames, which are free-standing or, for example, connected to the stands of the band saws. It should be noted that the concept of support roll must be interpreted in its broadest sense, and nl C The I 0 nu ut I nun: uno OO nu nu nu Otto II 0 0 0 0 000 on I to nan 10 15 20 526 793 ll be considered to include any of a component capable of performing the task of guiding or supporting the timber body during the splitting operation. It should also be pointed out that the description was based on the saw bands sawing vertically, ie. the timber body provides vertical cuts, but the invention is not limited by this, but the entire saw station can be rotated so that the saw bands, for example, saw horizontally or at some other angle to the horizontal plane. Furthermore, the machining part of the saw belts may comprise any suitable fiber-splitting agent, for example teeth, inserts, abrasive grains or the like. In addition to being displaceable across the feed direction, the support rollers with associated guide systems can also be displaceable in the axial direction, in order to enable fine adjustment of the location of the attachment points and to facilitate the assembly and disassembly of the saw belts. Finally, it should be pointed out that the dividing machine does not have to be located to perform a final operation in a saw line, but can also be used in other operations along the saw line or as an individual machine independent of a saw line.

Claims (7)

10 15 20 25 30 35 526 795 12 Patent claims A machine for dividing any curved wood bodies (2) into a number of smaller pieces of wood (9, 10, 11), comprising a feeder (3) with the task of feeding the individual wood body (2) into a saw station in the axial direction. (4), which is arranged downstream of the feed unit (3) viewed in the feed direction of the wood body (2), and which comprises at least three band saws (6), each individual band saw (6) comprising an endless saw band (carried) carried by a carrier (7) ( 8, 8 '), which is oriented parallel to the feed direction, and at least one saw band (8, 8') is axially displaced along the feed direction relative to the other saw bands, characterized in that it comprises at least four spacers removed from the feed unit (3). support rollers (12, 12 '), which are individually adjustably movable transversely to the feed direction and arranged in pairs, which are axially spaced apart and individually arranged to cooperate with at least one saw band (8, 8'), by being adjustable against the working body (2) u with an imaginary geometric reference line (R, R ') located transversely to the feed direction, located in the area of the cooperating saw band (8, 8'). Divider according to claim 1, characterized in that each individual support roller (12, 12 ') is connected to, and adjustably movable relative to said carrier. Dividing machine according to claim 2, characterized in that each individual support roller (12 ') is connected to the carrier (7) by means of a guide system (14), which extends from the V carrier and through the area circumferentially surrounded by that of the carrier burna saw band (8 '). IN Dividing machine according to one of Claims 1 to 3, characterized in that the feed unit (3) is adjustable between a first active state, in which the same directs the wood body (2) towards the sawing station (4), and a second, disengaged state. , in which the same compulsorily follows the curvature of the timber body (2). V V O: c 000 QOIO oc: O C OI sot I OOIO III a c 0 a 10 15 20 25 30 35 526 793 ga 13 Method for dividing any curved timber bodies (2) into a number of smaller pieces of timber (9, 10, 11), comprising the steps: that the individual timber body (2) is fed by means of a feeder (3) in the axial direction. in a saw station (4) located downstream thereof, and that said timber body (2) is fed against at least three saw bands (8, 8 ') acting in the saw station (4), which saw grooves parallel to the feeding direction and of which at least one is axial offset along the feed direction relative to other saw belts (8, 8 '), characterized by: that at least four support rollers (12, 12') spaced from the feeder, which are individually adjustably movable transversely to the feed direction and arranged in pairs, which are kept axially spaced apart and were for cooperates with at least one saw band (8, 8 '), is applied to the wood body (2) along two imaginary geometric reference lines (R, R') transversely relative to the feed direction located in the area of the respective cooperating saw bands. Method according to claim 5, characterized in that a relatively different saw band (8 ') located upstream of the saw band (8) saws a first groove in the wood body (2), and that said other saw bands (8') saw, relative to the first groove , flanking grooves in the same. Method according to claim 5 or 6, characterized in that said support rollers (12, 12 ') are applied to the wood body (2) upstream of the respective cooperating saw bands (8, 8').