Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
  • B27L—REMOVING BARK OR VESTIGES OF BRANCHES; SPLITTING WOOD; MANUFACTURE OF VENEER, WOODEN STICKS, WOOD SHAVINGS, WOOD FIBRES OR WOOD POWDER
  • B27L1/00—Debarking or removing vestiges of branches from trees or logs; Machines therefor
  • B27L1/08—Debarking or removing vestiges of branches from trees or logs; Machines therefor using rotating rings

Definitions

• the present invention relates to a barking tool for barking machines of the type having a rotation ring which is rotatable about an axis of rotation and which carries a plurality of barking tools, comprising a swinging arm which, at a free front end, has a processing means with a cutting edge substantially parallel to said axis of rota ⁇ tion and which, at an opposite rear end, is fixable to a tool shaft associated with the rotation ring and rotatable in relation thereto, the cutting edge of said processing means being resiliently applicable, by rotation of said tool shaft, against the circumferential surface of an unbarked log of wood, said arm having a front facing the feeding direction of the logs fed to the machine and form ⁇ ed with a climb-up edge, as well as a back opposite to said front.
• Barking machines of this type are available in seve- ral different designs which all include a rotation ring formed with a central hole through which the logs are fed in their longitudinal direction during the barking pro ⁇ cess.
• a number of barking tools usually five, are pro ⁇ vided on the circumference of the rotation ring.
• the bark- ing tools are in the form of swinging arms which are pivotable in a plane substantially perpendicular to the feeding direction of the logs and which are spring-loaded so as to be resiliently applicable against the circumfe ⁇ rential surface of the logs, adapting themselves to the irregularities thereof. Since the rotation ring rotates while the logs are fed in their longitudinal direction, the bark will be peeled off in long, helical strips.
• Fig. 9 of SE 430,391 illustrates another embodiment of a barking tool in which the swinging arm has been given a substantially U-shaped cross-section with two flanges to reduce the weight and stiffen the con ⁇ struction.
• the flanges are arranged to face the feeding direction of the logs to enable the flange closest to the circumferential surface of the log to serve as a climb-up edge. As above, this climb-up edge will prevent the bark from leaving the machine in the area before the rotation ring.
• FIG. 2 is a side view of the barking tool as seen in a direction parallel to the feeding direction of the logs
• FIG. 3 is a side view of the barking tool as seen per- pendicular to the feeding direction of the logs
• FIG. 4 is a side view of the barking tool as seen from an angle perpendicular to the view of Fig. 3
• FIG. 5 shows cross-sections of the barking tool taken according to the indications in Fig. 2
• FIG. 6 is a side view of the barking tool in operation. Description of the Preferred Embodiment
• the barking tool comprises a swinging arm 2 and a processing means 3 in the form of a releasable cutting steel which is fixed to the swinging arm by a bolt 4.
• the cutting steel has a front edge 5, serving as processing edge, which extends substantially parallel to the intended feeding direction of the logs.
• the rear end 6 of the barking tool is, by bolts 7, fixed to a holding member 10 which in turn is non-rotatably connected to a tool shaft 11.
• the present invention is applicable to a rotation- ring barking machine, which includes a plurality of bark ⁇ ing tools, preferably five, which are pivotably connected to a rotation ring (not shown) by the tool shafts 11.
• Figs 2, 3 and 4 illustrate in more detail the con ⁇ struction of the processing means 3.
• the inner edge 17 has an extension edge 17' on the inner part of the processing means 3 facing the back, the extension edge 17' extending almost up to the processing edge 5, more pre ⁇ cisely that end 18 of the processing edge which faces in the feeding direction of the logs.
• the edge 17' is arrang ⁇ ed on a wedge-shaped bead 19 provided on the processing means. Further, the climb-up edge 15 extends from, and on a level with, the end 20 of the processing edge facing the feeding direction of the logs. The edge 15' of the pro ⁇ cessing means facing the feeding direction forms an exten ⁇ sion of the climb-up edge. As seen in a plane perpendicu ⁇ lar to the axis of rotation, the climb-up edge 15 extends rearwards from the processing edge 5, while gradually increasing its distance from the inner edge 17, and has a slightly curved shape up to a point 21 where it turns so as to be on a level with the outer flange 14.
• the swinging arm 2 is slightly bent outwards contrary to the feeding direction at a point 26 and is slightly bent inwards in the feeding direction on a level with the point 21.
• This arrangement is meant to facilitate the removal of bark from the tool, since the front tool end with the barking edge will, in its entire ⁇ ty, rotate ahead of a plane which is perpendicular to the axis of rotation and is located ahead of the longitudinal extension of the tool shaft. Thus, the bark will be thrown out and away from the machine without any risk that it hits the holding member 10 or the rear end 6 of the tool.
• the bark-guiding surface of the second portion 12 is inclined relative to the vertical plane. This surface might also be vertically aligned, i.e.
• the flange 28 does not have a climbing-up or bark-guiding function since it is situated between the point 21 and the rear end 6 of the swinging arm.
• the flange 28 only serves to reinforce the swinging arm.
• the length of the bark- guiding surface 16 should be at least a third of the entire length of the swinging arm.
• the bark-guiding surface of the second portion 12 extends, as seen in a plane parallel to the axis of rotation, from a position close to the end of the processing edge facing the back and a distance con- trary to the feeding direction of the logs up to a point 29 where the second portion 12 turns towards the longitu ⁇ dinal extension of the swinging arm.
• the processing edge 5 can be compa ⁇ ratively long, and at the same as the swinging arm can taper a distance behind the processing edge to be more light.
• the bark will be broken contrary to the feeding direction immediately after having been peeled off, and is thus broken in rather short pieces, which is especially advantageous in the barking of logs with long- fibre bark. Finally, the bark is guided contrary to the feeding direction, which facilitates the removal away from the tool.
• the barking tool need not have a releasable processing means, but the cutting edge may be integrally formed with the swinging arm.
• fixing on the tool shaft can be per ⁇ formed in different ways, e.g. by welding.
• the bark-guiding surface 16 may be designed in many different ways. Thus, this surface need not be composed of two sub ⁇ stantially flat surfaces at an angle to one another, but it may have a continuous alteration of the angle, e.g. have an arcuate shape.

Landscapes

• Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Wood Science & Technology (AREA)
• Forests & Forestry (AREA)
• Debarking, Splitting, And Disintegration Of Timber (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=20381277

Family Applications (1)

Country Status (3)

Cited By (2)

Families Citing this family (1)

Citations (5)

• 1990
  • 1990-12-21 SE SE9004106A patent/SE469117C/sv not_active IP Right Cessation
• 1991
  • 1991-12-19 AU AU91087/91A patent/AU9108791A/en not_active Abandoned
  • 1991-12-19 WO PCT/SE1991/000880 patent/WO1992011119A1/en active Application Filing

Patent Citations (5)

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