Sawing system and method for sawing a workpiece

Abstract

Sawing system (100) comprising a rail guide (12) defining a longitudinal direction (14), a saw (10) arranged on the rail guide (12), a first saw material feed (16), a second saw material feed (18), a first carriage (20) comprising a first saw material support (22) and a first carriage drive (24), and a second carriage (32) comprising a second saw material support (34) and a second carriage drive (36), wherein the first saw material feed (16) is configured to transfer a first saw material (28) to the first saw material support (22), wherein the second saw material feed (18) is configured to transfer a second saw material (38) to the second saw material support (32), and wherein the first carriage drive (24) is configured to move the first carriage (20) with the first saw material (28) along the rail guide (12) along the longitudinal direction (14) past the saw (10) to cut the saw. first sawn material (28) in the longitudinal direction (14),and wherein the second wagon drive (36) is arranged to move the second wagon (32) with the second saw material (38) along the rail guide (12) along the longitudinal direction (14) past the saw (10) in order to saw the second saw material (38) in the longitudinal direction (14).

Description

[0001] The present invention relates to a sawing system and a method for sawing a workpiece using a saw.

[0002] Known examples of sawing systems from the prior art include so-called block band saw systems, which generally have one or two band saw stands whose positioning relative to each other is either fixed in a predefined manner (e.g., side by side) or variable (movable at least along one direction relative to each other). Furthermore, known sawing systems have a carriage that can be moved back and forth (or side by side) by means of a drive along a track that defines a longitudinal direction.

[0003] For example, EP 0 963 822 A2 discloses a device for cutting logs into boards, comprising a reciprocating carriage for transporting logs and a band saw. Furthermore, CN 103 978 267 A discloses a band saw system with two band saws.

[0004] The carriage serves as a support for the workpiece (for example, a log), which is fixed in a predefined position on the carriage before sawing, for example, using several clamping hooks. During the forward and reverse movements, the carriage transports the workpiece through the bandsaw stand, maintaining a specific position relative to the saw blade. Depending on the saw blade design, a sawn product (e.g., a board blank) is cut from the workpiece either only during the forward or reverse movement, or during both movements (in the case of a double-sided saw blade). The final thickness of the sawn product (e.g., board thickness) is determined by a pre-adjustable overhang between the workpiece and the saw blade before sawing, for example, by moving the carriage support transversely (perpendicular to the longitudinal direction).

[0005] In the case of band saws, the band saw blade is typically clamped between two band saw rollers mounted on the band saw stand and rotates around them at an adjustable sawing speed. The sawing direction of the band saw blade is usually perpendicular to the longitudinal direction.

[0006] Further processing steps can precede and / or follow the actual sawing process. For example, the workpiece can be measured beforehand using a measuring system (e.g., optical). Additionally, the slab (the first piece of the workpiece to be removed, which is unsuitable for further processing) can be machined using a machining unit as an alternative to sawing it off. Furthermore, the workpiece can be cut or trimmed in its transverse direction, for example, using a cut-off and crosscut saw. These preliminary processing steps primarily serve to straighten the workpiece.

[0007] The exact processing sequence for a state-of-the-art sawing system can therefore be summarized as follows:

[0008] In a first step, the workpiece is transferred to a support on the carriage at a transfer point using a lateral movement and then rotated into a predetermined position, either manually (e.g., via remote control by an operator) or automatically (e.g., via a camera system). Once the workpiece has reached the predetermined position, this position is fixed on the support using a clamping mechanism (e.g., clamping hooks).

[0009] In the next step, the workpiece is moved laterally relative to the bandsaw stand by means of a transverse movement of the support, such that a predefined overhang is created between the workpiece and the saw blade, defining the desired thickness of the sawn product. Alternatively or additionally, the bandsaw stand can be moved transversely.

[0010] After the predefined alignment, fixing, and relative movement of the workpiece, it is guided lengthwise past the saw blade by the carriage, thereby separating a (first) saw product from the workpiece. As soon as the saw product leaves the saw blade, the workpiece is moved again transversely relative to the saw blade by a predefined distance in order to produce another saw product of the desired thickness in the next sawing movement.

[0011] In some cases, it is also necessary to reposition or rotate the sawn material on the clamping carriage during or after processing to achieve a desired cutting pattern. This is usually accomplished using a log turner or sawn material turner. This log turner allows the sawn material resting on the carriage to be rotated around its longitudinal axis into the desired position.

[0012] Once the processing of a log is complete, the cart returns to its loading position and the previously described process begins again.

[0013] Both loading the saw carriage and rotating or positioning the workpiece on the carriage support require time during which no sawing can take place. Consequently, this loading or positioning time results in production and performance losses for the sawing system, which has negative economic consequences. The resulting time loss can amount to 10 seconds or more per workpiece.

[0014] FR 1 355 680 A discloses a sawing system with an oval, self-contained rail guide, wherein a saw is arranged on one longitudinal side of the oval and several material feeds are arranged on the other longitudinal side of the oval. Several carriages, each with a material support, can circulate on the closed rail guide.

[0015] FR 986,565 A discloses a sawing system with carriages suspended from a track, each capable of guiding a piece of material to be sawn in a uniform direction along a saw. The carriages can be returned to the starting point for a sawing operation via an auxiliary rail. US 3,503,428 A and US 3,731,578 A disclose further sawing systems with carriages that transport the material to be sawn.

[0016] US 4,665,786 A discloses a sawing system with a band saw that is moved on a rail in a longitudinal direction to saw material at different positions.

[0017] In view of this state of the art, it is therefore an object of the present invention to further develop a sawing system in such a way that the productivity of the sawing system can be increased.

[0018] The aforementioned problem is solved by a sawing system according to claim 1, which comprises a rail guide defining a longitudinal direction, a saw arranged on the rail guide, a first material feed, a second material feed, a first carriage comprising a first material support and a first carriage drive, and a second carriage comprising a second material support and a second carriage drive. The first material feed is configured to transfer a first piece of material to the first material support. The second material feed is configured to transfer a second piece of material to the second material support. The first carriage drive is configured to move the first carriage with the first piece of material along the rail guide in the longitudinal direction past the saw in order to saw the first piece of material longitudinally.The second carriage drive is configured to move the second carriage, carrying the second piece of wood, along the rail guide past the saw in the longitudinal direction, in order to saw the second piece of wood lengthwise. The rail guide has a beginning and an end. Viewed in the longitudinal direction, the sawing system defines a first feed area, a working area adjoining the first feed area, and a second feed area adjoining the working area. The first wood feed is located in the first feed area, the saw is positioned essentially in the center of the working area, and the second wood feed is located in the second feed area.

[0019] Furthermore, the problem is solved by a method for sawing using a sawing system according to claim 14.

[0020] One aspect of the new sawing system and the new process is that two separately driven carriages are arranged on the rail guide for processing the sawn material. The sawing system thus comprises a saw that cooperates with two carriages. At the beginning of the rail guide (upstream) is the first feed area (or the first loading and handling area) of the first carriage. Viewed longitudinally, the working area is located in a central section of the rail guide, extending longitudinally on both sides of the saw. The saw is preferably positioned substantially centrally (± 10%) within the working area. The sawing of the sawn material takes place within this working area. Furthermore, the sawn products are produced and removed within this working area. At the downstream end of the rail guide is the second feed area (or the first loading and handling area).The second loading and handling area of ​​the second carriage is arranged in the two feed areas. In each of these areas, the respective carriage is loaded with the sawn material and, preferably, the sawn material is aligned on the respective sawn material support. By organizing the sawing system into the first feed area, the working area, and the second feed area, trouble-free operation of the sawing system can be ensured, as the loading and handling of the sawn material takes place only in the feed areas, but not in the working area. This enables a highly efficient sawing process.

[0021] A key advantage of this design is that the aforementioned downtime, which occurs, for example, during the feeding or loading of the saw material onto the saw's support surface and / or during the alignment of the saw material, can be reduced or minimized. This makes it possible to increase the productive sawing time of the sawing system and thus the throughput of sawn products. This leads to more economically optimized operation of the sawing system.

[0022] The term "saw" in this context refers in particular to a motorized band saw, a motorized circular saw or a motorized miter saw, although other types of saws are also possible.

[0023] In preferred embodiments, the first and second carriages can each be moved independently back and forth on the rail guide. This means, for example, that the first carriage can move back and forth on the rail guide while the second carriage remains stationary (at the same time) and is being loaded with sawn timber.

[0024] By using the two carriages, it is possible, for example, to perform unproductive loading and / or manipulation work on the first carriage, while (at the same time) the second piece of material already positioned (i.e., rotated and aligned) on the second carriage is sawn by passing the saw.

[0025] As soon as the second carriage undergoes manipulation (e.g., realignment) of the second piece of wood, or processing of the second piece of wood is completed (i.e., the second carriage needs to be reloaded), it can return to its loading and manipulation zone. Simultaneously, the first carriage, now fully loaded, can follow it towards the saw to begin sawing the first piece of wood. It is advantageous if there is only a minimal dead time (during which no sawing takes place) between the completion of one sawing operation and the start of the other.

[0026] As soon as the first carriage needs to be reloaded after the sawing process has ended or been interrupted, or as soon as the first piece of saw material needs to be realigned or manipulated, it can move into its loading and manipulation position and the second carriage can move to the saw to saw the newly supplied or realigned second piece of saw material.

[0027] The first and second carriages thus enable alternating sawing of either the first or the second piece of material with minimal downtime. This increases the effective processing time of the material compared to conventional systems.

[0028] The term "rail guidance" is used here to refer to any type of guide rail that ensures the guided sliding or movement of a carriage. Advantageously, the rail guidance can be designed in the form of conventional rails.

[0029] The term "longitudinal direction" refers to the direction in which the rail guide is laid according to its length. The rail guide preferably runs in a straight line, from a starting position defined upstream of the saw to an end position defined downstream of the saw, along the longitudinal direction.

[0030] The first and second cars each have their own drive system. These drive systems allow the two cars to be moved back and forth along their length, as well as upstream and downstream.

[0031] The wording, “that the saw is arranged on the rail guide”, expresses that the saw is arranged laterally next to the rail guide, i.e. preferably in the direction of one track width of the rail guide.

[0032] The term "passing" means that the workpiece is guided through the saw blade with a predefined overhang (defined perpendicular to the longitudinal direction) so that the sawn product can be cut off. The thickness of the sawn product is defined based on this overhang, taking into account a loss width determined by the thickness of the saw blade.

[0033] In one embodiment, the first saw material feed is configured to transfer the first saw material to the first support in a transverse direction defined perpendicular to the longitudinal direction. Furthermore, it is preferred that the second saw material feed is configured to transfer the second saw material to the second support in a transverse direction defined perpendicular to the longitudinal direction.

[0034] This design has the advantage of minimizing the overall length of the sawing system in the longitudinal direction. Furthermore, feeding the material to be sawn perpendicular to the longitudinal direction reduces the risk of interference with the ongoing sawing process on the other carriage.

[0035] The term "transverse" does not necessarily mean perpendicular or orthogonal, but rather any feed at an angle other than 0°. Preferably, however, the feed is substantially perpendicular or orthogonal (i.e., at an angle of 90° ± 10%) to the longitudinal direction.

[0036] In a further embodiment, the first and / or the second feed area borders the work area, but preferably does not overlap with it.

[0037] This design clarifies that loading and handling operations taking place in the feed areas do not negatively affect the processing steps (sawing the workpiece) in the work area. Therefore, time losses due to loading and handling have no negative impact on the sawing process. The first and / or second feed area preferably does not overlap the work area, or only partially does so.

[0038] In a further embodiment, the first feed area is located upstream in the longitudinal direction starting from the saw, and the second feed area is located downstream in the longitudinal direction starting from the saw.

[0039] This design clarifies the positioning of the individual areas within the sawing system. The working area extends longitudinally both upstream and downstream of the saw, whereas the first infeed area is located further upstream without overlapping with the working area, and the second infeed area is located further downstream without overlapping with the working area.

[0040] In a further embodiment, the sawing plant also features a first sawdust discharge and a second sawdust discharge. The first and second sawdust discharges are designed to remove a saw product that has been produced by sawing the first or second sawdust in the longitudinal direction.

[0041] This design differs further from the usual setup of a sawing system. In conventional sawing systems, where saw products are generated in both the forward and reverse movements of the carriage, saw products accumulate both upstream and downstream of the band saw and are currently discharged as follows:

[0042] The sawn products accumulating downstream of the band saw are conveyed longitudinally via a conveyor system (e.g., roller conveyor or belt conveyor). The sawn products accumulating upstream are transported by another conveyor, located between the saw blade and a stand structure of the band saw (the band saw stand), through the band saw stand and onto the conveyor system located longitudinally downstream, from which they are then conveyed longitudinally.

[0043] After the sawn product has passed the band saw stand from upstream, it is conveyed by the same conveyor system used for sawn products from downstream. Particularly during rapid cutting, it is possible that the downstream transport system is still occupied by a sawn product that originated upstream (before the band saw stand), as this product has a longer path to travel (through the band saw stand). To avoid this, current technology operates the upstream and downstream conveyor systems from the saw at very high feed rates (i.e., rapid removal of sawn products). This makes reliable control of the removal of sawn products from the sawing system to other processes more difficult.

[0044] In particular, it is advantageous that this design eliminates the need to transport upstream sawn material through the band saw stand, as it can be removed via the first material discharge. Thus, unlike the prior art, the same downstream discharge system is no longer used, allowing both the first and second material discharges to operate at lower feed rates, which has a positive effect on the aforementioned control system.

[0045] In a further embodiment, the first sawdust discharge is configured to discharge the sawn product transversely to the longitudinal direction. Furthermore, it is preferred that the second sawdust discharge is configured to discharge the sawn product transversely to the longitudinal direction.

[0046] This design advantageously avoids this problematic removal situation. The sawn products are removed both upstream and downstream, perpendicular to the longitudinal direction. Therefore, the upstream and downstream sawn material removal do not interfere with each other.

[0047] In a further embodiment, the first sawdust removal is arranged upstream of the saw in the longitudinal direction, the second sawdust removal is arranged downstream of the saw.

[0048] It is preferred that both the first sawdust discharge and the second sawdust discharge are located in the working area of ​​the sawing system in order to avoid interaction with the first and second sawdust feed areas, respectively.

[0049] In a further embodiment, the saw has a band saw blade that defines a sawing direction during sawing, which is oriented perpendicular to the longitudinal direction.

[0050] The sawing direction refers to the direction of rotation of the band saw blade around two preferably existing band saw rollers, between which the band saw blade is tensioned, and around which the band saw blade is moved during sawing. The sawing direction is preferably parallel to an imaginary line connecting the centers of the two band saw rollers.

[0051] In a further embodiment, the band saw blade has saw teeth on both sides when viewed in the longitudinal direction.

[0052] This double-sided saw tooth design efficiently ensures that sawing of the material to be sawn can take place both when the first or second carriage moves from upstream to downstream and from downstream to upstream.

[0053] In a further embodiment, a first cellar chute is arranged upstream of the saw when viewed longitudinally. It is also preferred that a second cellar chute is arranged downstream of the saw.

[0054] Particularly when a cellar drop shaft is arranged on both sides, the sawing process using the sawing system according to the invention is advantageous.

[0055] In conventional sawmills, the first processing step involves a downstream movement of the saw carriage, creating an initial usable surface on the sawn material. This typically produces a section unsuitable for further processing, known as slab. This slab must be removed from the subsequent conveying process. Usually, the slab accumulates downstream of the saw and is conveyed laterally by shifting the conveying system (i.e., the roller conveyor or belt downstream of the saw) into a bottom-level opening, the so-called slab discharge, towards a residual wood disposal facility. The separated slab typically falls into this slab discharge chute immediately after being cut from the sawn material, thus allowing it to be removed directly from the further production process.

[0056] The new sawmill system features two cellar discharge chutes (advantageously located upstream and downstream of the saw) to easily remove bark generated upstream during the first processing step of the second sawmill as the second carriage passes the sawmill upstream. This eliminates unproductive empty runs for the second carriage (without processing), as the bark is removed during the upstream movement. Unlike previous systems, the removed bark can also be discharged through the first cellar discharge chute.

[0057] In a further embodiment, the first cellar chute is designed to collect bark that accumulates during the sawing of the first and / or second piece of wood. In a further advantageous embodiment, the second cellar chute is designed to collect bark that accumulates during the sawing of the first and / or second piece of wood.

[0058] In a further embodiment, a conveyor is also arranged on the saw, which is designed to tilt a rotary axis running parallel to the longitudinal axis.

[0059] The conveyor is preferably arranged in a region between the saw blade and the saw stand. Furthermore, it is preferred that the first material discharge point is arranged upstream of the conveyor, immediately following it. It is also preferred that the second material discharge point is arranged downstream, immediately following the conveyor. This configuration ensures smooth removal of the sawn products both upstream and downstream from the saw.

[0060] In order to dispose of the upstream slab during the first processing of the second sawn material as smoothly as possible, the conveyor is tiltable around the axis of rotation (especially foldable upwards) unlike in the prior art, so that when the slab is discharged upstream, only part of the first sawn material removal (a conveyor system set up for this purpose) is moved transversely to the longitudinal direction in order to open the first cellar discharge chute.

[0061] In a further embodiment, the first and second cars are designed to be coupled together in order to be moved simultaneously on the track while coupled.

[0062] The coupling can be implemented purely mechanically (for example, via catch hooks) and / or (electro-)magnetically and / or virtually (through a control-based coupling of the first and second wagon drives). When the first and second wagons are coupled, the first and / or the second saw material feed can preferably be configured to transfer an oversized saw material to the two coupled wagons.

[0063] The advantageous coupling of the first and second carriages makes it possible to use two smaller, lighter, and therefore more dynamically maneuverable carriages, each advantageously equipped with its own drive. This allows for the processing of large-diameter sawn timber (e.g., long logs or tree trunks). Due to the relatively low weight of the first and second carriages, high acceleration values ​​can be achieved, which are difficult to attain with a longer and heavier carriage typically required for processing long logs. Coupling the two carriages also allows for the integration of the two sawn timber supports, thereby increasing the number of clamping blocks used to secure the sawn timber to the support, particularly for processing larger-diameter sawn timber.This ensures a high level of dynamics for the respective carriage, even when processing longer pieces of sawn material.

[0064] In a further embodiment of the method according to the invention, the first and second carriages are moved essentially in alternating order along the longitudinal direction in order to saw the first and / or the second workpiece.

[0065] This design clarifies once again that the processing of the first and second pieces of wood preferably takes place in alternating sequence; that is, while, for example, the first carriage is being loaded with the first piece of wood or it is being positioned on the sawdust support, the processing of the second piece of wood is carried out by moving the second carriage back and forth. Once the processing of the second piece of wood is complete, or if the sawing process has to be interrupted due to repositioning the second piece of wood on the sawdust support, and once the loading of the first carriage and the positioning of the first piece of wood on the first sawdust support are complete, the processing of the first piece of wood can begin as soon as possible after the completion of the processing of the second piece of wood.

[0066] It is understood that the aforementioned embodiments and exemplary embodiments, as well as those to be explained below, can be combined not only in the specified combination but also freely without departing from the scope of the present invention. Furthermore, it is understood that the embodiments mentioned with regard to the sawing system also apply in equivalent form to the method according to the invention and its embodiments, without being mentioned separately. The same applies to embodiments of the method with regard to the sawing system.

[0067] Exemplary embodiments of the invention are shown in the drawings and are explained in more detail in the following description. They show: Fig. 1 an embodiment of the sawing system in a first processing position; Fig. 2 the embodiment of the sawing system in a second processing position; Fig. 3 the embodiment of a sawing system in a third processing position; Fig. 4 a schematic side view of a sawdust feeder; Fig. 5 a schematic side view of a sawdust removal system; and Fig. 6 a second embodiment of the sawing system.

[0068] Fig. Figure 1 shows a first embodiment of a sawing system according to the invention. The sawing system as a whole is designated by the reference numeral 100. In this case, the sawing system 100 is a band sawing system and comprises a band saw 10. Furthermore, the band sawing system 100 has a rail guide 12, which defines a longitudinal direction 14. Viewed in the longitudinal direction 14, the band saw 10 is arranged laterally to the side of the rail guide 12, i.e., outside of it, in a central region of the rail guide 12. In other embodiments not shown, the sawing system 100 could, for example, also be a circular sawing system.

[0069] The band saw system 100 also has a first saw material feed 16, which is upstream (in Fig. 1 left) of the band saw 10 is arranged laterally next to and outside the rail guide. Furthermore, the band saw system 100 has a second saw material feed 18, which is located downstream (in Fig. 1 (right) is located to the side of the band saw 10, next to and outside the rail guide 12.

[0070] Furthermore, the band saw system 100 has a first carriage 20. The first carriage 20 comprises a first saw support 22 and a first carriage drive 24. The first carriage drive 24 is, for example, integrated into the first carriage 20 and can be designed, for example, as any type of motor drive. In other advantageous embodiments, the first carriage drive 24 is arranged below the rail guide 12 or at an upstream or downstream end of the rail guide 12 and moves the first carriage via a cable pull. The first carriage 20 preferably has a number (e.g., two) of wheel axles (not shown) spaced apart from one another and oriented perpendicular to the rail guide 12, corresponding to the number of clamping blocks on the carriage. Each axle has two pairs of wheels 26. The first carriage 20 is guided on the rail guide 12 by means of the pairs of wheels 26.

[0071] The first sawlog support 22 is set up to receive the first sawlog 28. The first sawlog 28 is, for example, a round timber in the form of a tree trunk. Fig. 1 the first sawn material 28 is already lying on the first sawn material support 22 and is fixed on the first sawn material support 22 by means of two advantageous clamping blocks 30.

[0072] In order to change the position of the first sawn material 28 on the first sawn material support 22, for example to rotate or tilt it about the longitudinal direction 14, it is preferred that the first carriage 20 has a turning and rotating mechanism, for example in the form of a log turner, which enables rapid rotation in both directions about the longitudinal direction.

[0073] The band saw system 100 further comprises a second carriage 32, which includes a second workpiece support 34 and a second carriage drive 36. The second workpiece support 34 is designed to receive a second workpiece 38 and preferably to fix it in a predetermined position on the second workpiece support by means of the clamping blocks 30. The remaining features described with respect to the first carriage 20 apply analogously to the second carriage 32, without being redundantly mentioned.

[0074] In Fig. 1. The second sawdust feed 18 is set up to transfer the second sawdust 38 to the second sawdust support 34. The second sawdust 38 is in the case of Fig. 1 was still arranged on the second sawdust feed 18, so it had not yet been transferred to the second sawdust support 34.

[0075] Both the first and the second sawdust feed 16, 18 preferably have one or more conveying technologies (for example, roller conveyors, conveyor belts or cross chain transports) by means of which the respective sawdust 28, 38 can be transported both in the longitudinal direction 14 and in a transverse direction 40 running perpendicular to the longitudinal direction 14 and thus fed to the respective sawdust support 22, 34. Fig. Figure 1 shows an example of a transverse chain conveyor technology 42, by means of which the respective sawn material 28, 38 can be transported in the transverse direction 40.

[0076] Furthermore, the band saw system 100 has according to Fig. 1 a first sawdust removal 44, starting from the band saw 10 upstream (in Fig. 1 left) is arranged from the band saw. Furthermore, the band saw system 100 has a second saw material discharge 46, which extends downstream from the band saw 10 (in Fig. 1 right) is arranged from the band saw 10.

[0077] Both the first sawdust discharge 44 and the second sawdust discharge 46 are designed to discharge a saw product resulting from the sawing of the first and / or the second sawdust 28, 38 in the transverse direction 40. The discharge of the saw product 48 takes place along the transverse direction 40, but in the opposite direction to the feed direction, i.e., away from the rail guide 12. An exemplary discharge of the saw product 48 by the second sawdust discharge is shown in Fig. 2 shown. The resulting saw product 48 can, for example, be a board sawn off from the first and / or second cutting material.

[0078] The band saw system 100 can be divided into three different areas when viewed longitudinally. Upstream of the band saw 10 (at the left outer edge of the Fig. 1) A first feed area 50 is arranged in which the first saw material feed 16 is arranged. The first feed area 50 extends downstream along the longitudinal direction as far as required by the dimensioning of the first saw material feed.

[0079] Following the first feed area 50, a working area 52 adjoins, but preferably does not overlap. The working area 52 preferably extends both upstream and downstream of the band saw 10, with the band saw 10 being arranged substantially centrally within the working area 52. To the left and right (upstream and downstream) of the band saw 10, the first and second material discharges 44, 46 are also arranged within the working area 52. At the downstream edge of the Fig. 1 Following the downstream end of the working area 52, a second feed area 54 is connected, in which the second saw material feed 18 is arranged.

[0080] In the Fig. In the case shown in Figure 2, the band saw system 100 is shown in a second processing position, in which the first carriage 20, driven by the first carriage drive 24, has already passed the band saw 10 along the rail guide 12 in the longitudinal direction 14 with the first workpiece 28, and during this passage the first workpiece 28 has already been sawn in the longitudinal direction 14. During this sawing, the sawn product 48 was separated from the first workpiece 28 and can thus be discharged via the second workpiece discharge 46 in the transverse direction 40. In the Fig. In the position shown in Figure 2, the first carriage 20 is about to be moved upstream again by the first carriage drive 24, in order to saw the first piece of sawn material 28 again in the longitudinal direction when it passes the band saw 10 again.

[0081] In Fig. Figure 3 shows the band saw system 100 in a third processing position, in which the second carriage 32 has already been loaded with the second saw material 38 via the second saw material feed 18 and the second saw material 38 thus rests on the second saw material support 34 and is preferably fixed on it via the two clamping blocks 30.

[0082] In the first processing step of the first and second sawn timbers 28, 38, it is normally customary to remove a slab (a piece of wood that is not economically usable). Depending on whether the first or the second sawn timber 28, 38 is initially sawn, the slab is generated either upstream or downstream of the band saw 10 and is removed from the further processing process at these points.

[0083] For the discharge of the sawn material, a first conveying system 56 belonging to the first sawn material removal is preferably set up, in the transverse direction 40 such that the accumulating bark is discharged into a floor opening, the so-called first cellar discharge shaft 58 (see Fig. 4) can fall (in the case of Fig. 3 into the plane of the blade), to be disposed of. Furthermore, downstream of the band saw 10, a second conveying system 60 belonging to the second saw material removal 46 is set up, also to be moved in the transverse direction 40 in order to convey a slab accumulating downstream into an opening arranged under the second conveying system 60, the second cellar discharge chute 62 (see Fig. 4) to drop.

[0084] To ensure the discharge of the bark into the first and second cellar discharge chutes 58, 62 upstream and downstream, respectively, a conveyor 64 is tiltable about a pivot axis 66 running parallel to the longitudinal axis 14 (upwards, i.e., out of the plane of the blade). The conveyor 64 is, for example, a roller conveyor or other conveyor belt that, viewed longitudinally, is arranged between the first and second saw material discharge points 44, 46, more precisely between the first and second conveying systems 56, 58. Viewed transversely, the conveyor 64 is located between a band saw blade 68 (see Fig. 5) and a bandsaw stand 70. In Fig. 3 is conveyor 64, a roller conveyor.

[0085] Fig. Figure 4 shows a schematic view of the first or second sawdust feed 16, 18. As can be seen, the first or second sawdust 28, 38 is conveyed stepwise onto the first or second sawdust support 22, 34 by means of the sawdust feed 16, 18. In the Fig. In the case shown in 4, there is already sawdust 28, 38 on the sawdust support 22, 34. In addition, in Fig. Figure 4 schematically shows that saw material with different width dimensions can also be conveyed onto this saw material support 22, 34 by means of the saw material feed 16, 18.

[0086] In Fig. 4 is further shown that the feed of the sawn material 28, 38 is preferably monitored and / or controlled by measuring instruments, wherein in Fig. 4. An optical sensor 72 is arranged above the sawdust support 22, 34. The optical sensor 72 can preferably be designed in the form of a camera that communicates with a controller (not shown) such that the feed of the sawdust 28, 38 can be controlled via the images captured by the camera 72. In addition, Fig. 4 schematically depicts the first and second cellar drop shafts 58, 62.

[0087] Fig. Figure 5 shows a schematic view of the first and second saw material discharge 44, 46. Both the sawing process and the saw material feed and discharge are preferably monitored (audio-)visually by an operator 74 sitting in a driver's cab 76 in order to detect disturbances and errors in the band saw system 100 as early as possible. Fig. Figure 5 shows that preferably both the band saw 10 or the band saw blade 68 and the first and second workpiece supports 22, 34 are each tilted by an angle α = 17° relative to a vertical direction 78, since this angle has proven to be particularly advantageous in the prior art. Furthermore, the band saw blade 68 is clamped between two spaced-apart band saw rollers (not shown) and rotates around them, thereby defining a sawing direction 79.

[0088] In Fig. Figure 6 shows a second embodiment of the band saw system 100. In this embodiment, the first and second carriages 20, 32 are coupled to each other via a coupling 80 such that the first and second workpiece supports 22, 34 can preferably be used synergistically for supporting an extra-long workpiece 82 without the need for a larger carriage as a replacement. The coupling 80 between the first and second carriages 20, 32 is preferably implemented mechanically (via catch hooks), (electro-)magnetically, or virtually.

[0089] For example, with virtual coupling, it is possible to coordinate the first and second car drives 24, 36 in such a way that the first and second cars 20, 32 travel directly behind one another at a predefined distance, with the master-slave principle being a suitable option for this type of control. Here, for example, the second car 32 can act as the master, controlling the movement of the first car 20 via a coupling of the two drive controllers.

[0090] In the Fig. In the case shown in 6, both the sawdust supply and the sawdust discharge are designed with enlarged dimensions in accordance with the dimensioning of the extra-long sawdust 82.

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