WO2009061252A1

WO2009061252A1 - A bark-cutting device and a method of fitting a bark-cutting device to a barking machine

Info

Publication number: WO2009061252A1
Application number: PCT/SE2008/000630
Authority: WO
Inventors: Bror Eriksson
Original assignee: Iggesund Tools Ab
Priority date: 2007-11-08
Filing date: 2008-11-06
Publication date: 2009-05-14
Also published as: SE0702456L

Abstract

The invention concerns a bark- cutting device to be fitted to a barking machine comprising a rotatable, annular rotor with many barking arms (2). The bark-cutting device fits the area of a barking arm's free end adjacent a barking edge's (6,6') upstream end, in the log feeding direction, and comprises a bark-cutting edge (8), with a longitudinal extent substantially transverse the log feeding direction for pre-cutting bark before debarking occurs. The bark-cutting device is an accessory element (9), comprising an internally threaded or unthreaded hole (10) or a threaded shank and a wing (11), extending laterally from the shank or hole and provided with the bark- cutting edge (8), so the device is adapted for use as a nut, washer or bolt and is connected to the barking tool when connecting the barking tool (4) to the barking arm (2). The invention also concerns a combination barking tool and bark- cutting device, and a method of fitting a bark- cutting device to a barking machine.

Description

A BARK-CUTTING DEVICE AND A METHOD OF FITTING A BARK-CUTTING DEVICE TO A BARKING MACHINE

The present invention relates to a bark-cutting device of the kind configured to be fitted to a barking machine of the type comprising a rotatable, annular rotor, on which a plurality of barking arms are mounted, which are each pivotally connected at one end to the rotor to pivot in the plane of rota- tion of the rotor and their outer, free ends are oriented inwards to the open, annular centre of the rotor, and each carries a barking tool, comprising at least one barking edge, in order to provide, during rotation of the rotor and simultaneous longitudinal feeding of a log through the rotor, shearing off of bark from the log by resiliently pressing the ends of the barking arms and, thereby, the barking edges of the barking tools against the circumferential surface of the log, the bark-cutting device being adapted to be arranged in the area of the free end of a barking arm adjacent an upstream end of a barking edge, as seen in the direction of feeding of the logs, and comprising a bark- cutting edge, which has a longitudinal extension in a direction substantially transversely to the direction of feeding of the logs for pre-cutting the bark before debarking by means of the barking tool occurs. The invention also concerns a combination of a bark-cutting device and a barking tool and a method of fitting a bark-cutting device to a barking tool.

Background Art

In barking machines of the kind stated above, it is previously known to provide some kind of bark-cutting device which has a bark-cutting edge for pre-cutting the bark before it is sheared off by means of the barking tool. This may be advantageous, or even necessary in some cases, to prevent loose bark from peeling off in large chunks, for example during the season when the sap rises. Such large chunks may cause problems on the one hand because they get stuck in the barking machine or the log conveyors and, on the other hand, in connection with the subsequent processing of the bark, which is of- ten used as filling material, soil-improvement material or for combustion, in which cases it is desirable that the bark should be finely divided.

Different bark-cutting devices are known in the art. There are, for example, barking machines that have a separate rotor which is equipped with swinging arms that carry bark-cutting tools and which is positioned before the actual barking machine, as seen in the direction of feeding of the logs. Of course, a solution of this kind is efficient, but more expensive than it has to be. There are also barking tools that are specially designed with a bark- cutting edge located at the upstream end of the barking edge. Besides these barking tools being more expensive than conventional barking tools, they also have another major drawback, namely that the bark-cutting edge has a tendency towards wearing out long before the barking edge wears out. This means that either the barking tool will have to be discarded before the barking edge is worn out, which means increased costs, or the logs will be barked using a poorly working bark-cutting edge during the latter part of the life of the barking tool, which may cause operational problems during barking or incomplete dividing of the bark.

Brief Description of the Invention The object of the present invention is to eliminate the problems and drawbacks of prior-art bark-cutting devices and to provide a bark-cutting device in the form of an accessory element, which can be easily combined with a barking tool, if required, and be easily removed without the need to replace the barking tool. At least this object is achieved by a bark-cutting device as claimed in claim 1.

The invention also concerns a combination of a barking tool and a bark-cutting device and a method of fitting a bark-cutting device to a barking machine, the objects of which are substantially the same as that stated above. These objects are achieved by a combination as claimed in claim 6 and a method as claimed in claim 12.

The above objects are achieved by providing a bark-cutting edge on an accessory element in the form of a nut, a washer or a bolt, which is connected to the barking tool when connecting the barking tool to the barking arm, the bark-cutting edge being supported on the outer end of an arm or a wing, which extends laterally from a shank or a hole. In the cases where the accessory element is in the form of a nut, with an internally threaded hole, or a bolt with a threaded shank, the accessory element will in itself serve as a fasten- ing element for connecting the barking tool to the barking arm. In cases where the accessory element is in the form of a washer or a sleeve with an unthreaded through hole, the barking tool and the accessory element have to be connected by means of two separate, co-operating fastening elements in the form of a bolt and a nut, such that the bolt shank extends through holes in the barking arm, the barking tool and the accessory element and the bolt head engages a seat on one side of the barking arm or the accessory element and the nut engages a seat on the other of the two.

To prevent rotation of the accessory element due to operative forces during barking of logs, for one thing the barking tool is non-pivotally retained in per se known manner in a seat on the barking arm and, for another, the accessory element is non-pivotally retained in a seat on the barking tool. The latter rotation-preventing seat can be achieved in different ways, for example by a head of the nut, a non-circular washer or bolt engaging a seat surface surrounded by non-circular walls and/or by a shoulder or a shank of the nut, washer or bolt having a non-circular cross-sectional shape and penetrating in a hole in the barking tool which has a non-circular cross-sectional shape.

In one embodiment of the invention, which will be described in detail below, the accessory element is in the form of a nut with an internally threaded hole, which nut serves as a fastening element for cooperating with a bolt with a threaded shank for simultaneous connection of the barking tool to the barking arm. In the embodiment shown, the hole in the accessory element is a through hole, but could also be a non-continuous hole, a "blind hole". One advantage of the accessory element being in itself a fastening element in the form of a nut or a bolt instead of a washer or a sleeve is that the total height of the assembly can be made smaller than if an additional separate fastening element would have to be mounted.

The bark-cutting edge, when the accessory element has been fitted to a barking machine, is positioned with its longitudinal extent in a direction sub- stantially transversely to the intended direction of feeding of the logs. This should not be interpreted as meaning that the bark-cutting edge must be absolutely perpendicular to the direction of feeding of the logs. In fact, according to one embodiment of the invention, the bark-cutting edge is positioned at an angle in the range 1-25°, preferably 8-20° and most preferred 16-18° relative to the direction of feeding of the logs, such that the other end of the bark- cutting edge which leads in the direction of rotation is located further upstream relative to the direction of feeding of the logs than one end of the bark- cutting edge which trails in the direction of rotation. This is advantageous in that the logs move during barking, so that the bark is sheared off in a helical path across the circumferential surface of the log. By the bark-cutting edge having an angle that roughly corresponds to the lead angle of the helical path relative to the longitudinal extent of the log, the bark-cutting edge will cut through the bark with less resistance, which results in less energy consump- tion, less wear to the bark-cutting edge and less damage to the wood.

By using a bark-cutting accessory element according to the invention, it is possible to rapidly and easily equip a barking tool with a bark-cutting edge, whenever desired, without having to change the barking tool. The need for bark-cutting edges may arise quickly, for example during the fall or spring when the timber may be frozen in the morning but not frozen later in the day. Reversibly, it is possible to rapidly and easily remove the bark-cutting edges from the barking tool without having to change the barking tool when the bark- cutting edges are no longer required, which is advantageous since power consumption is greater with bark-cutting edges than without and the damage to the wood also increases slightly.

By arranging the bark-cutting edge on an accessory element, which is mounted on the barking tool by means of the same fastening elements or in the same spot as the fastening elements for securing the barking tool to the barking arm, there is no need to provide a separate seat surface on the bark- ing tool or the barking arm for the bark-cutting device or holes intended for separate fastening means in the form of bolts or screws, which would increase costs in connection with the provision of such components. Moreover, if the barking machine were to be operated without the bark-cutting device there would be a risk of the seat surface and the fastening holes being worn out and, in this case, a dummy accessory element would be required in the place of the bark-cutting device to protect the seat surface and the fastening holes, which would require the manufacture, storage, transport and mounting of one more component.

In the embodiments of the invention described and illustrated below, the barking tool is symmetrical and has two barking edges. This allows the barking tool to be turned when one barking edge is worn out, so that the second barking edge is placed in a barking position. Furthermore, a barking tool of this kind can be used both in barking machines where the rotor rotates clockwise as well as counter-clockwise, as seen in the direction of feeding of the logs. On the other hand, the bark-cutting devices must be specially designed for clockwise or counter-clockwise operation since they will be mirror- inverted relative to one another. It will be appreciated, however, that the in- vention is also applicable to other types of barking tools, i.e. of the kind that is non-symmetrical and/or has a single barking edge.

An exemplified embodiment of the invention will be described below, reference being made to the accompanying drawings.

Brief Description of the Drawings

Fig. 1 is a front view of a rotatable rotor comprising barking arms, while barking a log; Fig. 2 is a schematic perspective view of a barking arm, while barking a log; Figs 3 and 4 are perspective views of a bark-cutting accessory element according to the invention; Fig. 5 is a perspective view of the outer end of a barking arm with the bark-cutting accessory element being disengaged;

Fig. 6 is a perspective view similar to that of Fig. 5, but with the bark- cutting accessory element being mounted;

Fig. 7 is a view from above of the outermost end of a barking arm illustrating the angle of the bark-cutting edge;

Fig. 8 is a view from above according to Fig. 7, but of a barking arm adapted for counter-clockwise rotation of the rotor; Fig. 9 is a perspective view according to Fig. 5 but of an alternative embodiment of the accessory element; and Fig. 10 is a perspective view according to Figs. 5 and 9 of yet another embodiment of the accessory element.

Detailed Description of an Embodiment of the Invention

Reference is first made to Fig. 1 , which is a front view of a schematically illustrated rotor 1, which forms part of and is rotatably mounted in a barking machine (not shown in detail). The rotor carries, in all, five barking arms 2, which are each at one end pivotally connected to the rotor via a pivot shaft 3 (Fig. 2) in any known or convenient manner as would be apparent to those skilled in the art. At their other, free end, arms 2 are provided with a barking tool 4. The barking arms 2 are influenced by a spring force (not shown), which strives to move the outer free ends of the arms, carrying the barking tools, in towards the centre of the rotor. In connection with longitudinal feeding of a log 5 in a direction towards the plane of the paper during simultaneous rotating of the rotor 1 , the barking arms will press a barking edge 6 of each barking tool 4 against the circumferential surface of the log during shearing off of bark 7 on the log in a helical path, as illustrated in Fig. 2, in which, for the sake of simplicity, only one barking arm 2 is shown. As will be understood, the rotor 1 has a central opening 1' through which log 5 passes during the debarking operation.

According to the invention, each of the barking tools 4 is provided with a bark-cutting edge, as indicated by reference numeral 8 in Fig. 1. A solid knife edge, as shown, is most preferred, but the present invention comprehends all forms of cutting edges that are capable of slitting bark as further described below. The longitudinal extent of the bark-cutting edge has substantially the same direction as the helical path of movement of the barking tool across the circumferential surface of the log and is located adjacent the upstream end of the barking edge 6, i.e. the end 6" (Figs. 5 and 6) of the barking edge that first makes contact with the arriving log. By designing and positioning the bark-cutting edge 8 in this way, the bark will be cut in helical strips before or at the same time as the barking edge 6 shears off the bark from the circumferential surface of the log. As a result, the barking edge will shear off only the helical bark strip that has been pre-cut by the bark-cutting edge 8 and this prevents the formation of large chunks of bark regardless of whether it is the sap season or the bark has a great tensile strength in the longitudinal direction of the log. Reference is made below to Figs 3-7, which illustrate the barking tool 4 and the bark-cutting edge 8 in greater detail. In the embodiment shown, the barking tool is of the kind disclosed in WO 2005/030447, which has two barking edges 6, 6' and which, therefore, is reversible in order to locate a new barking edge in a position for barking when the other edge has been worn out. Furthermore, the barking tool and the seat surface of the barking tool on the barking arm are designed such that the barking tool can be displaced and rotated to allow setting of the contact angle of the currently used barking edge at different degrees of aggressiveness relative to the circumferential surface of the log. This function and the necessary features are described in detail in the above-mentioned document, the disclosure of which is incorporated herein by reference, and, thus, will not be described in more detail herein.

The bark-cutting edge 8 is arranged on an accessory element 9, which in the embodiment shown includes a mounting portion which includes a mounting extension 12 provided with an internally threaded through aperture or hole 10 and serves as a nut described hereinafter. In its upper portion, the accessory element 9 is provided with a laterally extending arm or wing 11. The bark-cutting edge 8 is formed on the outermost free end of wing 11. In this specification the term mounting portion means that portion of the accessory element 9 which is used to mount the accessory element 9 onto the barking arms or barking tool and from which the wing 11 extends.

A bark-cutting device or accessory element 9 designed in this way is adapted to serve as a fastening element, in this case a nut, as part of a mounting assembly or means for securing the bark cutting device and the barking tool 4 to the barking arm. This is done using, for example, a bolt 13 with an externally threaded shank inserted in a circular hole 10' formed in the barking arm 2 and an oval hole 4' in the barking tool 4, and screwed in the hole 10 in the bark-cutting accessory element 9. The barking tool 4 is designed with an oval-shaped seat 14, which is adapted to receive a corre- sponding, oval-shaped profile 15 (part of the mounting portion of the accessory element 9) on the underside of the bark-cutting accessory element 9. As a result of the complementary surfaces on the barking tool 4 and the accessory element 9, the barking tool 4 and the bark-cutting accessory element 9, upon tightening of the bolt 13, will be non-rotatably connected relative to the barking arm and the bark-cutting accessory element also will be non-rotatably connected relative to the barking tool, as illustrated in Fig. 6. This means that the bark-cutting edge 8 will be positioned adjacent the end 6" of the barking edge 6 which is located closest to the direction of feeding of the logs, i.e. the end that first makes contact with the arriving logs.

In the embodiment shown, the mounting extension 12 is centred on the bark-cutting accessory element 9. By forming the element 9 with the mounting extension displaced slightly to one side or the other of the illustrated centred position, the barking tool can be mounted in a displaced manner at more or less aggressive contact angles relative to the circumferential surfaces of the logs to be barked, as is described in greater detail in WO 2005/030447 mentioned above.

It is preferred to arrange the bark-cutting edge 8 with its longitudinal extent slightly angled relative to a direction that is perpendicular to the direc- tion of feeding of the logs, so that one end of the bark-cutting edge which leads in the direction of rotation is located further upstream relative to the direction of feeding of the logs than one end of the bark-cutting edge which trails in the direction of rotation. This is illustrated by the angle α in Fig. 7, which shows a view from above of the outer end of a barking arm with a mounted barking tool and a bark-cutting accessory element. To obtain the best results, the angle α should correspond to the lead angle of the helix defined by the path taken by the barking tool along the circumferential surface of the log during barking. The lead angle is a measure of the inclination of the helix in a plane perpendicular to the axis of rotation of rotor 1 and corre- sponds to the angle α for which the bark cutting edge 8 must be aligned to follow the helical path. In most applications, this lead angle will be in the range of 5-40° depending on the diameter of the log 5, the speed at which the log passes through the rotor during operation, and the rotation speed of the rotor 1. It is therefore desirable to have angle α formed to most closely approximate the range of values encountered in operation, preferably being between 8-20° and most preferably, between 16-18°.

Fig. 7 illustrates an embodiment adapted for clockwise rotation of the rotor as seen in the direction of feeding of the logs, which, in the embodiment shown, is from below and in the direction indicated by the arrow. If the device of Fig. 7 is inverted, as shown in Fig. 8, then it will be adapted for counterclockwise rotation of the rotor as seen in the direction of feeding of the logs, which, in this case, is from above and in the direction indicated by the arrow. By using an accessory element 9 according to the invention and symmetrical barking tools 4, it is thus possible to use the same barking tool for both clockwise and counter-clockwise rotation even if bark-cutting edges 8 are being used. This was not possible in prior-art barking tools having integrated, fixed bark-cutting edges, in which case the tools had to be made according to ei- ther a clockwise design or a counter-clockwise design, which further contributed to raising the costs. It is true that the bark-cutting accessory element 9 according to the invention must be made according to both a clockwise design and a counter-clockwise design, but the cost of this accessory element is, in any case, considerably lower than that of a barking tool. A bark-cutting device according to the invention offers a simple and inexpensive accessory element, which can be easily associated with a barking tool whenever there is a need to pre-cut the bark before it is sheared off by means of the barking tool. It is just as easy to remove the accessory element when pre-cutting is no longer required, in which case the accessory element is replaced by a nut 16, as shown in Fig. 5, which is without the wing 11 and the bark-cutting edge 8 of the invention.

As mentioned previously, a bark-cutting accessory element according to the invention does not have to come in the form of a nut with an internally threaded hole 10, according to the embodiment described above and illus- trated in the drawings, but could also be provided in the form of a bolt 17 with a threaded shank, which is inserted in the holes in the barking tool 4 and the barking arm 2, respectively and co-operates with a nut 18 on the opposite side of the barking arm, as is illustrated in fig 9, or in the form of a washer 19, which has an unthreaded hole and is clamped together with the barking tool 4 with the aid of, for example, a threaded bolt 20 and a nut 18, as is illustrated in fig 10.

Claims

1. A bark-cutting device of the kind that is configured to be fitted to a barking machine of the type comprising a rotatable, annular rotor (1) on which a plurality of barking arms (2) are mounted, which are each at one end pivo- tally connected to the rotor and adapted to be pivoted in the plane of rotation of the rotor and whose outer, free ends are oriented inwards to the open, annular centre of the rotor, and which each carry a barking tool (4), comprising at least one barking edge (6, 6'), in order to provide, during rotation of the rotor and simultaneous longitudinal feeding of a log (5) through the rotor, shear- ing off of bark from the log by resiliently pressing the ends of the barking arms and, thereby, the barking edges of the barking tools against the circumferential surface of the log, the bark-cutting device being adapted to be arranged in the area of the free end of a barking arm adjacent an upstream end of a barking edge, as seen in the direction of feeding of the logs, and comprising a bark-cutting edge (8), which has a longitudinal extent in a direction substantially transversely to the direction of feeding of the logs for pre-cutting the bark before debarking by means of the barking tool occurs, c h a r a c t e r i s e d in that the device is in the form of an accessory element (9), comprising an internally threaded or unthreaded hole (10) or a threaded shank and a wing (11) which extends laterally from the shank or the hole and which is provided with the bark-cutting edge (8), such that the device is adapted for use as a nut, a washer or a bolt and is connected to the barking tool (4) when connecting the barking tool to the barking arm (2).

2. A bark-cutting device as claimed in claim 1 , c h a r a c t e r - i s e d in that the accessory element (9) has an internally threaded hole (10) or a threaded shank which allows it to be used as a fastening element for connecting the barking tool (4) to the barking arm (2).

3. A bark-cutting device as claimed in claim 1 or 2, c h a r a c t e r i s e d in that the bark-cutting edge (8) forms an angle (α) relative to the direction of feeding of the logs such that one end of the bark-cutting edge which leads in the direction of rotation is located further upstream relative to the direction of feeding of the logs than one end of the bark-cutting edge which trails in the direction of rotation.

4. A bark-cutting device as claimed in claim 3, c h a r a c t e r - i s e d in that the angle is in the range 1-25°, preferably 8-20° and most preferred 16-18° relative to the direction of rotation.

5. A bark-cutting device as claimed in any one of the preceding claims, c h a r a c t e r i s e d in that the accessory element (9) is in the form of a nut with a through hole (10).

6. A combination of a barking tool and a bark-cutting device, the barking tool (4) having at least one barking edge (6, 6') and being of the kind that is configured to be fitted to a barking machine of the type comprising a ro- tatable, annular rotor (1) on which a plurality of barking arms (2) are mounted, which are each at one end pivotally connected to the rotor and adapted to be swung in the plane of rotation of the rotor and whose outer, free ends are oriented inwards to the open, annular centre of the rotor, and which each carry a barking tool of this kind in order to provide, during rotation of the rotor and simultaneous longitudinal feeding of a log (5) through the centre of the rotor, shearing off of bark from the log by resiliently pressing the ends of the barking arms and, thereby, the barking edges of the barking tools against the circumferential surface of the log, while the bark-cutting device is adapted to be arranged in the area of the free end of a barking arm adjacent an upstream end of a barking edge, as seen in the direction of feeding of the log, and comprising a bark-cutting edge (8), which has a longitudinal extent in a direction substantially transversely to the direction of feeding of the logs for pre-cutting the bark before debarking by means of the barking tool occurs, c h a r a c t e r i s e d in that the bark-cutting device is in the form of an accessory element (9), which comprises an internally threaded or unthreaded hole (10) or a threaded shank and a wing (11), which extends laterally from the shank or the hole and which is provided with the bark-cutting edge (8), such that the accessory element is adapted for use as a nut, a washer or a bolt and is con- nected to the barking tool (4) when connecting the barking tool to the barking arm (2) and that the barking tool has a positioning seat (14) for receiving the bark-cutting accessory element in a manner that prevents rotation.

7. A combination as claimed in claim 6, c h a r a c t e r i s e d in that the accessory element (9) has an internally threaded hole (10) or a threaded shank to allow it to be used as a fastening element for connecting the barking tool (4) to the barking arm (2).

8. A combination as claimed in claim 6 or 7, c h a r a c t e r - i s e d in that the bark-cutting edge (8) forms an angle (α) relative to the direction of feeding of the logs such that one end of the bark-cutting edge which leads in the direction of rotation is located further upstream relative to the direction of feeding of the logs than one end of the bark-cutting edge which trails in the direction of rotation.

9. A combination as claimed in claim 8, c h a r a c t e r i s e d in that the angle is in the range 1-25°, preferably 8-20° and most preferred 16- 18° relative to the direction of rotation.

10. A combination as claimed in any one of claims 6-9, c h a r a c t e r i s e d in that the accessory element (9) is in the form of a nut with a through hole (10).

11. A combination as claimed in any one of claims 6-10, c h a r - a c t e r i s e d in that the barking tool (4) is symmetrical and adapted for use together with a bark-cutting accessory element (9), which is adapted for both clockwise and counter-clockwise rotation of the rotor (1).

12. A method of fitting a bark-cutting device to a barking machine of the type comprising a rotatable, annular rotor (1) on which a plurality of barking arms (2) are mounted, which are each at one end pivotally connected to the rotor and adapted to be swung in the plane of rotation of the rotor and whose outer, free ends are oriented inwards to the open, annular centre of the rotor, and which each carry a barking tool (4), comprising at least one barking edge (6, 6'), in order to provide, during rotation of the rotor and simultaneous longitudinal feeding of a log (5) through the centre of the rotor, shear- ing off of bark from the log by resiliently pressing the ends of the barking arms and, thereby, the barking edges of the barking tools against the circumferential surface of the log, the bark-cutting device being adapted to be arranged in the area of the free end of a barking arm adjacent an upstream end of a barking edge, as seen in the direction of feeding of the logs, and comprising a bark-cutting edge (8), which has a longitudinal extent in a direction substantially transversely to the direction of feeding of the logs for pre-cutting the bark before debarking by means of the barking tool occurs, comprising the steps of providing a bark-cutting device in the form of an accessory element (9), which has an internally threaded or unthreaded hole (10) or a threaded shank and a wing (11), which extends laterally from the shank or the hole and which is provided with the bark-cutting edge (8), and ensuring, when connecting the bark-cutting accessory element to the barking tool (4), connection of the barking tool to the barking arm (2), the bark-cutting accessory element serving as a nut, a washer or a bolt adapted to co-operate with a matching bolt (13) and/or nut.

13. A method as claimed in claim 12, comprising the further step of providing a bark-cutting accessory element (9), which is provided with an internally threaded hole (10) or a threaded shank and using the bark- cutting accessory element as a fastening element for connecting the barking tool (4) to the barking arm (2).

14. A method as claimed in claim 12 or 13, comprising the further step of positioning the bark-cutting edge (8) at such an angle (α) relative to the direction of feeding of the logs that one end of the bark-cutting edge which leads in the direction of rotation is located further upstream relative to the di- rection of feeding of the logs than one end of the bark-cutting edge which trails in the direction of rotation.

15. A method as claimed in claim 14, comprising the further step of positioning the bark-cutting edge (8) at an angle of between 1-25°, preferably 8-20° and most preferred 16-18° relative to the direction of rotation.

16. A bark cutting device for use in a barking machine having at least one barking arm extending transversely to the direction of travel of a log through the machine and a barking tool having a through opening therein for use in mounting the tool to the arm and at least one barking edge, said bark cutting device including a bark cutting edge, a mounting portion, and a wing laterally extending from said mounting portion to a free end adapted to be located adjacent said barking edge when the bark cutting device is mounted on the barking tool; said bark cutting edge being located on the free end of said wing to extend generally transversely to the direction of travel of a log through said machine when the bark cutting device is mounted on the barking tool in the machine; and means for securing the barking tool and bark cutting device together on a barking arm.

17. A bark cutting device as defined in Claim 16 wherein said barking tool has an aperture formed therein and said means for securing the barking tool and bark cutting device comprises an internally threaded aperture formed in the mounting portion of the bark cutting device and a bolt adapted to ex- tend through a barking arm and the aperture in the barking tool into threaded engagement with the threaded hole of the bark cutting device.

18. A bark cutting device as defined in Claim 16 wherein said barking tool has an aperture formed therein and said means for securing the barking tool and bark cutting device comprises an unthreaded aperture formed on the mounting portion of the bark cutting device, a bolt and nut assembly wherein the bolt is adapted to extend through a barking arm and the apertures in the barking tool and mounting portion of the bark cutting device for engagement with the nut.

19. A bark cutting device as defined in Claim 16 wherein said barking tool has an aperture formed therein and said means for securing the barking tool and bark cutting device comprises an at least partially thread shank located on the mounting portion of the bark cutting tool adapted to extend through the aperture in the barking device and a nut for engagement with said shank.

20. A bark cutting device as defined in any of Claims 16-19 wherein said mounting portion of the bark cutting device includes means for cooperating with surface portions of the barking device for locating the position of the cutting edge relative to the barking tool and preventing rotation of the bark cutting device relative to the barking tool.

21. A device for use in log barking machines having at least one barking arm, said device comprising a barking tool having at least one bark cutting edge and a separate bark cutting device including a mounting portion, and a wing laterally extending from said mounting portion to a free end adapted to be located adjacent said barking edge when the barking tool and bark cutting device are mounted on the barking arm; said free end of said wing having a bark cutting edge formed thereon to extend generally transversely to the direction of travel of a log through said machine when the bark cutting device is mounted on the barking tool and barking arm in the machine; and means for securing the barking tool and bark cutting device together on a barking arm.

22. A device as defined in Claim 21 wherein said barking tool has an aperture formed therein and said means for securing the barking tool and bark cutting device comprises an internally threaded aperture formed in the mounting portion of the bark cutting device and a bolt adapted to extend through a barking arm and the aperture in the barking tool into threaded engagement with the threaded hole in the bark cutting device.

23. A device as defined in Claim 21 wherein said barking tool has an aperture formed therein and said means for securing the barking tool and bark cutting device comprises an unthreaded aperture formed on the mount- ing portion of the bark cutting device, a bolt and nut assembly wherein the bolt is adapted to extend through a barking arm and the apertures in the barking tool and mounting portion of the bark cutting device for engagement with the nut.

24. A device as defined in Claim 21 wherein said barking tool has an aperture formed therein and said means for securing the barking tool and bark cutting device comprises an at least partially thread shank located on the mounting portion of the bark cutting tool adapted to extend through the aperture in the barking device and a nut for engagement with said shank.

25. A device as defined in any of Claims 21-24 wherein said mounting portion of the bark cutting device includes means for cooperating with surface portions of the barking device for locating the position of the cutting edge relative to the barking tool and preventing rotation of the bark cutting device rela- tive to the barking tool.