EP0963822B1 - Device and method for subdividing logs - Google Patents

Abstract

At least one additional band-saw unit (26) is provided next to the first band-saw unit (24) and like the first unit it also has a band-saw blade (38) with teeth oriented in both directions. The second band-saw blade is vertically offset from the first band-saw blade (36) by a distance equal to the width of one of the boards. A drive mechanism (28, 30) is provided for each band-saw unit, capable of moving the two units away from each other at right angles to the direction of the tree trunk conveyor when this direction is changed. An Independent claim is also included for a method for sawing up tree trunks into boards.

Description

• einem in zwei entgegengesetzten Richtungen hin und her verfahrbaren Längsförderer für die Baumstämme,
• mindestens zwei Bandsägeaggregaten, die am Längsförderer angeordnet sind und jeweils ein Bandsägeblatt aufweisen, das in beiden Richtungen gezahnt ist, wobei die Bandsägeblätter um die Breite eines Brettes senkrecht zur Richtung versetzt sind, und
• einer Verfahreinrichtung für die Bandsägeaggregate, mittels derer die Bandsägeaggregate bei jedem Wechsel der Richtung senkrecht zu den Richtungen gegenläufig verstellbar sind.

The invention relates to a device for cutting tree trunks into boards with

• a longitudinal conveyor for the tree trunks, which can be moved back and forth in two opposite directions,
• at least two band saw units, which are arranged on the longitudinal conveyor and each have a band saw blade that is toothed in both directions, the band saw blades being offset perpendicular to the direction by the width of a board, and
• a traversing device for the band saw units, by means of which the band saw units are adjustable in opposite directions each time the direction is changed.

The invention further relates to a method for dividing tree trunks in boards, conveyed on a longitudinal conveyor which the tree trunks in several passes in opposite each other Direction using at least two in the directions aligned and serrated band saw blades at least two band saw units are sawn, whereby the band saw blades by the width of a board perpendicular to the Direction are offset, and furthermore the band saw units every time the direction changes perpendicular to the direction be adjusted.

A device and a method of the aforementioned type are known from US-A-4,317,398.

If you use a band saw unit to cut tree trunks used a single band saw blade, so are different Configurations possible. The band saw blade can e.g. just be serrated on one side. You then need one to split it up Tree trunk in n boards a total of n + 1 saw cuts. About that In this case, the tree trunk must go after each pass through the band saw unit e.g. over a round trip back in the starting position is placed in front of the band saw unit, so that a second pass can follow.

It is alternatively known, additionally on one or both sides Span heads to provide with the so-called rinds on both sides of the tree trunk. In this way a saw cut is saved on both sides, so that only n - 1 cuts are required.

It is also known alternatively to use band saw blades, which are serrated on both sides. Then the tree trunk must be on one Longitudinal conveyors are conveyed in opposite directions can be operated back and forth.

From the above-mentioned US-A-4 317 398 is a sawmill device known with band saw units. With the known The tree trunk to be processed is used for the device two holders clamped at its front ends. The Holders are part of a longitudinal conveyor with which the on this Tree trunk clamped in the direction of its longitudinal axis and can be moved here. In the area of movement of the tree trunk there are two band saw units on the opposite Long sides of the tree trunk are in engagement with it. The band saw units are equipped with band saw blades with teeth on both sides Mistake. The band saw blades are opposite to Adjustable longitudinal axis of the tree trunk. So that is achieved that with every change in the conveying direction of the tree trunk Band saw blades one step at a time, i.e. on the longitudinal axis of the tree trunk to be moved so that then another board at the next stroke of the longitudinal conveyor can be sawed off, the thickness of the travel of the band saw blades in the step perpendicular to the direction of conveyance of the longitudinal conveyor equivalent. The two band saw blades move with successive, i.e. gradually, towards each other.

"Longitudinal conveyor" is within the scope of the present invention on the other hand, to understand a block band saw carriage known per se, which can be moved axially on a rail. The tree trunk will on one side of the log band saw carriage, namely that of the band saw opposite long side by means of so-called clamps kept at the same time a certain orientation of the tree trunk enable on the log band saw carriage. In this way can be the time to perform the entire cutting process the number of saw cuts can be significantly reduced However, this does not change, even if in a further alternative configuration also in this case on both sides arranged span heads are used.

It is also known from sawmill technology, so-called Tandem units to use, where two band saw blades are provided, which are perpendicular to the conveying direction of the longitudinal conveyor are spaced, usually by the width of a board. The two bandsaw blades are common staggered, i.e. they are also in the direction of conveyance of the longitudinal conveyor offset against each other. During the run of the tree trunk then comes the one further out Band saw blade and then the one offset by a board thickness inner band saw blade engaged.

For this reason, it is not possible to use such tandem units to be used with band saw blades toothed on both sides. When the tree trunk returns, that would be the case now first engage the inner band saw blade at the front, which is not possible for manufacturing reasons is.

From US-A-4 879 659 a sawmill is known from of the tree trunks with a constant conveying direction a band saw unit run, the two one-sided toothed band saw blades having. These are on the opposite Sides of the tree trunk engaged. The band saw unit in Upstream of the conveying direction are two chipper heads, which the First flatten the trunk sideways.

A corresponding sawmill system is also in US-A-4 637 443, in which the tree trunks also pass through a band saw unit of the type explained above be flattened on both sides.

Document US-A-4 846 237 describes a method and one Device for sawing round logs. It takes one Circular saw unit use. The circular saw unit is in two successive passes over the fixed Move tree trunks away. The tree trunks are between the two passages by 180 ° in relation to their longitudinal axis, turned.

Document US-A-3 318 347 describes a method and one Device for multiple saws, in which the to be processed Tree trunk in a constant direction through several Band saw units are promoted to a variety of Make longitudinal cuts in the tree trunk. The several band saw units are in different ways in the conveying direction the tree trunks are staggered on the sides.

The invention has for its object a device and to further develop a method of the type mentioned at the beginning, that the disadvantages mentioned above are avoided. In particular, a significant increase in performance compared to conventional devices.

• der Längsförderer einen Blockbandsägewagen mit Spannböcken aufweist, die den jeweils zu zerteilenden Baumstamm auf einer ersten Längsseite des Blockbandsägewagens halten,
• die Bandsägeaggregate auf einer zweiten, den Spannböcken gegenüberliegenden Längsseite des Blockbandsägewagens und in den Richtungen hintereinander angeordnet sind, und
• die Bandsägeaggregate bei jedem Wechsel der Richtung derart gegenläufig zur zweiten Längsseite verstellbar sind, daß das jeweils äußere Bandsägeblatt beim Verfahren des Baumstammes vor dem jeweils inneren Bandsägeblatt in Eingriff mit dem Baumstamm kommt.

In a device of the type mentioned, this object is achieved in that

• the longitudinal conveyor has a log band saw carriage with clamps which hold the log to be cut in each case on a first longitudinal side of the log band saw carriage,
• the band saw units are arranged on a second longitudinal side of the block band saw carriage opposite the clamping blocks and in the directions one behind the other, and
• the band saw units are adjustable in opposite directions to the second long side each time the direction is changed so that the respective outer band saw blade comes into engagement with the tree trunk when the tree trunk is moved in front of the respective inner band saw blade.

• der jeweils zu zerteilende Baumstamm mittels Spannböcken eines Blockbandsägewagens des Längsförderers auf einer ersten Längsseite des Blockbandsägewagens gehalten wird,
• die Bandsägeblätter auf einer zweiten, den Spannböcken gegenüberliegenden Längsseite des Blockbandsägewagens und in den Richtungen hintereinander in Eingriff mit dem Baumstamm gebracht werden, und
• die Bandsägeaggregate bei jedem Wechsel der Richtung derart gegenläufig zur zweiten Längsseite verstellt werden, daß das jeweils äußere Bandsägeblatt beim Verfahren des Baumstammes vor dem jeweils inneren Bandsägeblatt in Eingriff mit dem Baumstamm kommt.

In a method of the type mentioned, the object is achieved in that

• the tree trunk to be cut in each case is held on a first longitudinal side of the block band saw carriage by means of trestles of a block band saw carriage of the longitudinal conveyor,
• the band saw blades are brought into engagement with the tree trunk on a second longitudinal side of the log band saw carriage opposite the clamping supports and in the directions one after the other, and
• the band saw units are adjusted with each change of direction in opposite directions to the second long side, that the respective outer band saw blade comes into engagement with the tree trunk when moving the tree trunk in front of the respective inner band saw blade.

The object on which the invention is based is achieved in this way completely solved.

According to the invention, namely, each time the direction of the Longitudinal conveyor the radial position of the band saw blades relative to Axis of the longitudinal conveyor interchanged, so that the previously inner Band saw blade now moves into the outer position and vice versa. As a result, when the tree trunk returns, it initially gets caught the band saw blade now on the outside, the one at the forward was engaged first, as desired becomes.

The band saw units are for this purpose with the mentioned Moving devices provided, a variety of embodiments is conceivable. So provided in an extreme case be, two completely independent band saw units with two as well to provide independent moving devices that only can be operated in push-pull mode via a common controller. Alternatively, however, combined units are also conceivable, where e.g. a common drive motor for both band saw blades is used and yet a common moving device, which only have a suitable swivel gear desired alternating movement of the band saw blades.

In preferred embodiments of the invention is in itself provided in a known manner, the tree trunks at least initially to be machined on one side, which is why they are also known per se Span heads are provided on the side of the longitudinal conveyor.

There are different types of tree trunks Cutting sequences conceivable. As part of these cutting sequences it may be useful to change the tree trunks at one of the directions the longitudinal conveyor by 180 ° about its longitudinal axis. This way it is easier to just put the logs on band saw unit arranged in one side of the longitudinal conveyor Bring intervention.

It is further understood that within the scope of the present invention also more than two band saw blades under the corresponding Position changes can be used. Jumps are also over integer multiples of board thicknesses when adjusting the band saw blades conceivable in the radial direction. Finally, you can the band saw blades can also be adjusted radially by any amount when wood products of different thicknesses are produced boards, planks and beams.

Further advantages result from the description and the attached one Drawing.

Fig. 1

eine äußerst schematisierte Draufsicht auf ein Ausführungsbeispiel einer erfindungsgemäßen Sägewerksanlage, in einer ersten Arbeitsstellung;

Fig. 2

die Sägewerksanlage gemäß Fig. 1, jedoch in einer zweiten Betriebsstellung; und

Fig. 3 bis 5

drei schematisierte Darstellungen zur Erläuterung einer Folge von Sägeschnitten nach drei unterschiedlichen Ausführungsbeispielen der Erfindung.

Embodiments of the invention are shown in the drawing and are explained in more detail in the following description. Show it:

Fig. 1

an extremely schematic plan view of an embodiment of a sawmill system according to the invention, in a first working position;

Fig. 2

the sawmill system of Figure 1, but in a second operating position. and

3 to 5

three schematic representations to explain a sequence of saw cuts according to three different embodiments of the invention.

In Fig. 1 is a total of 10 sawmill system, more precisely said a section of an entire sawmill system. In the sawmill 10, tree trunks should be Band saws are divided into boards.

A longitudinal conveyor of the sawmill system, generally designated 11 10 preferably comprises a block band saw carriage known per se 12, the on a guide rail 13 in two opposite directions Directions can be moved, such as with a double arrow 15 indicated. On the block band saw carriage 12 is located in Fig. 1 shows a tree trunk 14a, which moves to the left in Fig. 1 is, as indicated by an arrow 16a. The tree trunk 14a is by means of so-called clamps 17 on one long side Log band saw carriage 12 held.

The tree trunk 14a is located in Fig. 1 in the conveying direction shortly before a Spanerkopf 18, the individually or in pairs 18, 18 'arranged on one or both sides of the longitudinal conveyor 12 is. The span head 18 is perpendicular to the conveying direction standing axis 20 rotatable, as indicated by an arrow 22. The Spanerkopf 18 serves in a manner known per se for chipping the so-called "rind", i.e. the farthest external bark section of the tree trunk 14.

After passing the span head 18, the tree trunk 14a arrives in the area of two band saw unit 24, 26 in the conveying direction are arranged one behind the other. The band saw units 24, 26 are on the side opposite the jacks 17 the block band saw carriage 12 is arranged.

The band saw units 24, 26 are designed to be movable, and also in a direction perpendicular to the conveying direction of the longitudinal conveyor 11. Two fixed displacement devices 28, 30, for example fluidically actuated piston-cylinder units provided to the band saw units 24 and 26 in the mentioned Direction of travel to be adjusted, as with double arrows 32 and 34 indicated.

In the operating position shown in Fig. 1 is the first Band saw unit 24 a little more from the block band saw carriage 12 or spaced from the tree trunk 14a as the second band saw unit 26. The difference in distance of the band saw units 24, 26 from Longitudinal conveyor 12 corresponds exactly to the width of one to be sawn Boards, as will be explained.

The band saw units 24 and 26 are each with a rotating Band saw blade 36 or 38 provided. Since these are in the same Positioned on the band saw units 24, 26 has 1, the first band saw blade 36 consequently a distance from the block band saw carriage that is one board thicker 12 as the second band saw blade 38.

If the tree trunk 14a now after passing the spanhead 18 arrives in the area of the band saw units 24, 26 consequently, first through the first band saw blade 36 external cut made in tree trunk 14a, while only then a little further through the second band saw blade 38 internal saw cut is generated.

When the tree trunk 14a the band saw units 24, 26 completely has happened, is in the working position shown in Fig. 2 the conveying direction of the longitudinal conveyor 11 switched, so that it now runs from left to right in Fig. 2. This is indicated by the arrow 16b in the tree trunk 14b in Fig. 2.

At the same time, the movement devices 28, 30 were in the way actuated that now the second band saw unit 26 the larger Distance from block band saw carriage 12 during the first Band saw unit 24 moved closer to the block band saw carriage 12 has been. The distance between the band saw blades 36, 38 to one another corresponds again to the thickness of one to be sawn Board. The band saw blades 36 and 38 are in both directions toothed towards, as in FIGS. 3 to 5 in detail is recognizable. This means that the band saw blades 36 and 38 in Fig. 1 sawing both from the right and from the left can be.

In addition, tree trunk 14b was either unidirectional adjusted perpendicular to the conveying direction of the longitudinal conveyor 11 or the band saw units 24, 26 were jointly on the Log band saw carriage 12 to be adjusted. In this way it was achieved that by the band saw blades 36, 38 two more Cuts are made at two further positions of the tree trunk 14b are, as explained below with reference to FIGS. 3 to 5 will be.

The game explained above, being after walking past of the tree trunk 14 on the band saw units 24, 26 both the Direction of conveyance of the longitudinal conveyor 11 switched as well radial position of the band saw units 24, 26 and / or the Tree trunk 14 is adjusted, is now repeated if necessary several times, as also explained with reference to FIGS. 3 to 5 will be until the tree trunk 14 finally in the desired number of boards is dismantled.

3 to 5 are three different according to the invention Procedure for sawing the tree trunks 14 shown. Each 3 to 5 on the left are the two toothed on both sides Band saw blades 36 and 38 are shown, wherein in the 3 and 4, only these band saw blades 36, 38 are used 5, in addition in the case of FIG. 5 the chipper 18 or the chipper 18 and 18 'on both sides of the Longitudinal conveyor 11 are provided.

In the right part of FIGS. 3 to 5, a radial section through the tree trunk 14 is shown. In the illustrated embodiment, a total of seven boards a, b, c, d, e, f, g are to be produced. The rinds S ₁ and S ₂ on both sides are to be removed. The sawing operations, ie the passages of the tree trunk 14 past the band saw units 24, 26, are designated by Roman numerals I ...

In the exemplary embodiment according to FIG. 3, in the first pass I the rind S _{1 is cut} off with the second band saw blade 38, while the first band saw blade 36 runs past the rind S ₁ on the outside. In the second round II, the first two boards a and b are separated. The tree trunk is now turned on the block band saw carriage 12, ie rotated through 180 ° about its longitudinal axis, as shown by a dash-dotted line in FIG. 3. As a result, in the third pass III, only the opposite rind S _{2 is cut} off, specifically by means of the first band saw blade 36, while the second band saw blade 38 runs past the rind S ₂ on the outside. The third passage III takes place again as shown in FIG. 1.

In the fourth round IV, the boards f and g are sawn off, while in the fifth round V the boards c, d and e are generated.

In this embodiment, compared to a configuration, in the case of a band saw blade with a toothing on one side only sawed, a productivity increase of 73% was achieved.

In the first modification of this method, which is shown in FIG. 4, both the rind S ₁ and the first board a are separated in the first pass I. When returning, boards b and c are sawn off in the second round II. The tree trunk is now turned again on the log band saw carriage 12, so that both the second rind S ₂ and the board g can be sawn off in the third pass III. In the fourth round IV, boards d, e and f follow.

This embodiment of the invention is compared with the already mentioned state of the art an increase in productivity achieved by 110%.

In the further variant according to FIG. 5, the span heads 18 and 18 'already described for FIGS. 1 and 2 are finally used. Then a total of three passes I, II and III (with a turning of the tree trunk 14 after the passage II) are sufficient to saw all seven boards a to g, the rinds S ₁ and S ₂ before the first passage through the band saw units 24 and 26 were machined.

In this case the productivity increase is 129%.

Claims (6)

1. An apparatus for dissecting logs (14) into boards (a, b, c, d, e, f, g) comprising

   a longitudinal conveyor (11) for the logs (14), the conveyor (11) being adapted to be moved reciprocally in two opposite directions (15),

   at least two band saw assemblies (24, 26) arranged adjacent the longitudinal conveyor (11) and having each a band saw blade (36, 38) toothed in the two directions (15), the band saw blades (36, 38) being offset perpendicularly to the direction (15) by the width of a board (a, b, c, d, e, f, g), and

   a displacement unit (28, 30) for the band saw assemblies (24, 26) by means of which the band saw assemblies (24, 26) may be reciprocally displaced perpendicularly to the directions (15) at each alternation in direction (15);

   characterized in that

   the longitudinal conveyor (11) comprises a block band saw carriage (12) having clamps (17) for holding the particular log (14a) to be dissected on a first lateral side of the block band carriage (12),

   the band saw assemblies (24, 26) are arranged on a second lateral side of the block band saw carriage (12) opposite the clamps (12) and are arranged one behind the other along the directions (15), and

   the band saw assemblies (24, 26) are adapted to be displaced reciprocally relative to the second lateral side at each alternation in direction (15), such that during the displacement of the log (14a) the respective outer band saw blade (36) comes into engagement with the log (14a) prior to the respective inner band saw blade (38).
2. The apparatus of claim 1, characterized in that next to the band saw assemblies (24, 26) a chipping head (18, 18') is arranged along the direction at least on one side of the longitudinal conveyor (11).
3. A method of dissecting logs (14) into boards (a, b, c, d, e, f, g), the logs (14) being conveyed on a longitudinal conveyor (12), wherein the logs (14) are sawn in a plurality of passes (I, II, III, IV, V) in reciprocating directions (15) by means of at least two band saw blades (36, 38) of at least two band saw assemblies (24, 26), the band saw blades (36, 38) being oriented in the directions (15) and toothed in both directions (15), the band saw blades (36, 38) being offset perpendicularly to the directions (15) by the width of a board (a, b, c, d, e, f, g), and the band saw assemblies (24, 26), further, being reciprocally displaced perpendicularly to the direction (15) at each alternation in direction,
   characterized in that

   the particular log (14a) to be dissected is held by means of clamps (17) of a block band saw carriage (12) of the longitudinal conveyor (12) on a first lateral side of the block band saw carriage (12),

   the band saw blades (36, 38) are brought into engagement with the log (14a) one behind the other along the directions (15), and on a second lateral side of the block band saw carriage (12) opposite the clamps (17), and

   the band saw assemblies (24, 26) are displaced reciprocally relative to the second lateral side at each alternation in direction (15), such that during the displacement of the log (14a) the respective outer band saw blade (36) comes into engagement with the log (14a) prior to the respective inner band saw blade (38).
4. The method of claim 3, characterized in that the logs (14) are flattened by chipping at least on one side prior to reaching the first band saw blade (36).
5. The method of claim 3 or 4, characterized in that the band saw blades (36, 38) are each displaced reciprocally by a width of a board at an alternation in direction of the longitudinal conveyor (11).
6. The method of one or more of claims 3 to 5, characterized in that the logs (14) are rotated about 180° about their longitudinal axes at each alternation of direction of the longitudinal conveyor (11).

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