FI104542B - Chipping machine for timber, especially for round timber - Google Patents

Description

104542

Chipper for lumber, especially round wood

BACKGROUND OF THE INVENTION The present invention relates to a chipper for use in the plate industry, in particular for circular wood, to minimize the thickness distribution of chips produced by a chipper, which device includes a rotatable body having a chipboard surface, the chip blades partially extending as the part rotates 10, the cutting edges of the blades move substantially along a common surface, and means for providing a relative feed movement between the wood and the cutting blades.

There are three main types of machining equipment available on the market: - Shaft shaft with external machining blades (Messerwelle); Y; - Blade periphery with internal cutting blades: 20 Messerring, Ringflaker, Strander):. t - Disc cutting radius with radial cutting blades:, ·. (Disc flaker)

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In the first two devices, the cutting blades are located horizontally on the surface of the cylinder rotating about its axis in the axial direction or almost in the axial direction.

• · \\\ In the last, the blades are centered vertically

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radially or almost radially at the face of the rotating disk.

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· * · * · It is common for all devices to be powered by I

• · timber in bundles or as a continuous stream, with blades »·«: z 2 104542 cutting thin chips starting from the side surfaces of the trees with the blades substantially parallel to the cause of the trees. In some devices, the trees are fed either by gravity or by force feeding toward the cutting blades. In other devices, the bundle of wood 5 is locked in place and the cutting blades are fed against the wood.

Typically, devices on the market use chip blades, and in addition small scratch blades 10, which cut the removable chip into the desired length in the fall direction. The width of the chips is randomly formed as they break after they have been removed from the chopping blades.

The thickness of the 15 chips formed in gravity feeding devices is in principle determined by the projection of the blades and, in forced feeding devices, by the speed of the forced feeding. The target thickness of the chips varies from 0.3 to 0.7 mm depending on the application. It is essential that the thickness distribution of the chips is narrow, which is why the forced-feed machines 20 also tend to select the blade projection close to the target thickness.

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However, in known devices, the thickness of the chip produced varies considerably. Especially in gravity fed a a ·. . On 25 devices this is a problem.

To eliminate this problem, the wood chipper according to the invention is so arranged and the device according to the invention is characterized in that: In the direction of rotation of the 30 rotatable body members, a guide surface is formed between two successive • · V * cutting blades for the timber to be processed in the chipper, such that

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1 ·; ·· '. as the part rotates, the distance between the surface of movement of the cutting edges of the cutting blades I · t φ · · «i 3 104542 increases steadily from zero at t to the cutting edge of the cutting blade, t being the projection corresponding to the desired cutting thickness moving toward the blade.

The device according to the invention is based on the realization that the variation in the thickness of the chip is mainly due to the fact that between the contact points of the chipper blades the wood is off the wood guide surface of the cylinder or disc of the chipper 10. For reasons of manufacturing technology, the guiding surfaces between the blades of cylindrical devices are made cylindrical and the respective guiding surfaces of the wafer cutters are planar. As a result, the immediately cut wood of the blade is behind the blade 15 from the guide surface and collides thereafter before the next cutting blade. In this case, the wood may move freely, or be impacted in the opposite direction to the feed direction by the impact of the collision, resulting in the chip cut by the next blade not being as thick as the previous one. At its worst 20, this situation is such that only one in two of the blades cuts the wood as the wood resonates over the guide surface. . blade protrusion.

• · · '/' As a consequence of the above, the particle produced • · · · ... The thickness varies considerably and the capacity of the cutting machine • • · * is reduced because some of the blades do not cut the wood at all.

In contrast, in the device according to the invention, the guide surface between the blades is shaped such that it guides the wood continuously throughout the cutting process, thereby achieving the desired result. ··· • · · * · 1 1 inch, very narrow chip thickness distribution, thus stabilizing the most important dimension of the chip, namely the thickness.

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Advantageous further developments of the invention are set forth in the dependent claims.

The invention will now be described in more detail with reference to the accompanying drawings, in which:

Figure 1 shows a schematic embodiment of a cutting device according to the invention with internal cutting blades.

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Fig. 2 shows a cutting device according to a second embodiment of the invention, which in the example of the figure is formed by a disc chipper with radial cutters, shown in a partial section perpendicular to the radial direction of the disc.

Figure 1 shows schematically a chipper for cutting a bundle of circular trees 7.

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The device comprises a pivotable with respect to its central axis 12. . a body part 1 having a surface 2 with cutting blades 3 /; wherein the cutting blades 3 partially protruding from the surface 2 are (t <'arranged spaced apart so that as the body 1 ««' / 25 rotates, the cutting edges 4 of the blades 3 move substantially • · · · 'along the common surface 5.

The device further includes means designated 6 to provide a relative feed movement between the circular trees 7 and the surface 2 of the chassis blades 3 having a cutting blade 3. 1 1 si. 1, the means 6 will raise the body portion 1 in the direction of the arrow 13 towards the stationary wood bundle ·; ·· against which lastutusterät 3 begin to cut thin chip and tree-5 104 542 7 side surfaces of the wood bundles starting from the bottom. The chips detached by the chisel blade 3 exit through the chute opening 15 in front of the chisel 3.

In the prior art solution, the surface of the body part 1 provided with a chisel blade 3 is formed by a cylindrical surface designated by dotted lines, denoted by reference numeral 2, which has the disadvantage of a large variation in thickness of the chip produced, as stated in the description.

To eliminate this drawback, the cutting device according to the invention is arranged so that in the direction of rotation 8 of the rotating body 1 of the cutting device, a guide surface 9 is formed between the distance 11 between the trajectory surface 5 and the guide surface 9 increases as the forward blade moves towards the next blade.

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The distance denoted by reference numeral 11 preferably increases evenly. and, in particular, so that its value increases with chipboarding; from the value 0 at the cutting edge 4 of the blade 3 to t · I I · 't, where t is the desired chip thickness • * j, of the blade 3. 25 corresponding protrusion.

The guide surface 9 may be formed by one or more pieces connected to the body member 1 or the guide face 9 may be integral with the body member 1.

The guide surface 9 is preferably a planar surface.

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shown in Figure 2 is of the type lastutuslaite kiekkolas-tuaja, wherein the body portion 1 forms the rotatable with respect to the central axis of the disc 12, which is moved wood bundles with respect to the direction of the arrow 14.

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In the prior art solution, the surface provided with the cutting blades 3 is a planar surface according to the surface 2 shown by dotted lines. In the solution of the invention, on the other hand, a guide surface 9 is provided between two successive cutting blades 3, similar to the solution of Figure 1, such that when the body 1 rotates, the distance 11 between the moving surface 5 and the guide surface 9 van while moving toward the incoming blade.

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Claims (2)

1. Levyteollisuudessa käytettävä lastutuslaite puutavaraa, erityisesti pyöröputa, varten lastutuslaitteella aikaansaatavien lastujen paksuusjakauman minimoimiseksi, johon laitteeseen kuuluu pyöritettävä runko-osa (1) cargo equipment (3) on järjestetty velin päähän toisistaan site, one runko-1 o osan (1) pyöriessäterien (3) playcavat särmät (4) liikkuvat oleellisesti pitkin yhteistä pintaa (5), yes elimet (6) puutavarien (7) (3) velisen suhteellisen syöttöliikkeen aikaansaamiseksi, tunnettu siitä, one lastutuslait-teen pyöritettävän runko-osan (1) pyörimissuunnassa (8) kahden peräkkäisen lastutusterän (3) veliin on muodostettu ohjauspinta runko-osan (1) pyöriessä loadutusterien (3) playkavien särmien (4) liikeradan muodostaman pinnan (5) yes ohjauspin nan (9) velinen etäisyys (11) kasvaa tasaisesti lastutusterän (3) playkaavan sarmän (4) kohdalla olevasta arvosta o arvoon t, jolloin t on lastutusterän (3) haluttua lastun paksuutta vastaava ulkonema, noble kul-20 vastana teräva siirryttäessä. * · I '·: 2. Patenttivaatimuksen 1 mukainen laite, tunnettu siitä, etä ohjauspinnan «I · i i‘ \. (9) muodostaa tasopinta. • ii • · · • • 1 1 • • · 9 9 • · · • ff • · · • · · t · «· • · • Il III • · • · I» · 9 I r »III« IIII · • • 1 · «> • 1 · •> • · III g · • · tt · 8 104542 5 1.1 The disc industry useful wood clamping machine, especially round wood to minimize the coarse distribution of the clamps generated by the wood-cleaning machine, which machine has a rotatable body part (1 ) having a surface (2) provided with cutting edge (3), from which said surface (2) partially projecting cutting edge (3) is arranged spaced from each other such that as the body part (1) rotates the edges (3) And cutting means (4) substantially along a common surface (5), and means (6) for effecting a relative feeding movement between the wood product (7) and the cutting edges (3), characterized in that in the rotatable body part (1) of the clamping machine. rotational direction (8) between two successive cutting edges (3) forms a guide surface (9) f In the wood cleaning machine (7) treated wood product (7) ensures that as the body part (1) rotates, the distance (11) between the surface (5) of the cutting edge (3) of the cutting edge (3) and the guide surface (9) continuously increases from the the value is zero at the cutting edge (4) of the cutting edge (4) to the value t, where t is the projection of the cutting edge (3) corresponding to the desired thickness of the buckle, at the transition from the leading edge to the next edge. 20 2. Machine according to claim 1, characterized in that the guide surface (9) is formed by a pian surface. «· A • · 4 aa • · a« aa • a «· i • * a a · · taa a a a a a a a a a a a a a a a a a a a a a r: <t i lit It · III I aaa a I a a a