CN1910023A - Method for enhancing operation of a debarking roller assembly, as well as pick-up roll to be included in a debarking roller assembly - Google Patents

Abstract

The invention relates to a method for improving the operability of a stripping roller arrangement (1), and a pick-up roller (6) included in a stripping roller arrangement (1) for improving the operability of the roller arrangement, the Said roller arrangement is adapted to remove bark (2) from a stream of wood traveling in the transverse direction of the roller (3) of the roller arrangement and to accommodate the tree (5) and the bark (2) stripped from the tree, and to make the bark ( 2) Wrapping at least partially around the trees (5) and wedged between the trees or between the trees and the roller arrangement. In said method, at least in one position of the debarking roller device (1), the tree (5) undergoes a combined lifting movement, lateral movement and rolling around the longitudinal axis of the tree (5) so that the current position in said at least The tree at one location is at least temporarily and at least partially separated from the debarking roller arrangement (1) and other trees (5) currently on the roller arrangement.

Description

Method for improving the operability of a skinning roller device and a pick-up roller included in a skinning roller device

technical field

The invention relates to a method according to the preamble of claim 1 for improving the operability of a skinning roller arrangement. The invention also relates to a pick-up roller according to the preamble of claim 2 , included in a debarking roller arrangement for improving the operability of the roller arrangement.

Background technique

It is important for pulp quality to keep the amount of bark that ends up in chips with the tree as low as possible. The bark is usually stripped from the surface of the trees in a drum debarker where relative motion and friction of the trees relative to each other causes the bark to be stripped from the surface of the trees. Loose crushed bark mostly falls on the bark conveying device arranged below the peeling cylinder through the bark hole of the peeling cylinder. However, loose bark removed in long strips or in large sheets tends to follow the tree as it emerges from the output of the drum debarker. This difficult-to-bark tree includes a variety of hardwood species such as eucalyptus, locust, hickory, and birch.

If the bark is wound in the middle of the tree in individual strips or bark balls (herein a bark ball means a pile of bark consisting of more or less intertwined bark and which may also include blocks, chips, etc.) from the drum Coming out of the output of the debarker, most of this bark should be removed before shredding or other such operations. Partial debarking is possible with purpose built roller units. However, it is difficult to remove bark balls and some bark strips with rollers: a closed-space wood-saving (wood block) roller device leaves almost all bark balls and some loose bark in the wood stream, while large Spatial roller installations remove most of the loose bark and even some bark balls, but at the same time cause substantial loss of wood.

Applicant's earlier Finnish patent application 103717 discloses a device suitable for removing all kinds of bark, especially long bark and bark balls, from a wood stream containing wood and bark, said device being capable of preventing contact with trees at the same time. skin together to unnecessarily remove wood. The device comprises at least one vibrating roller as part of a conveying device carrying the stream of wood, and a plurality of rotatable rollers disposed downstream of the vibrating roller transversely to the direction of travel of the stream of wood, below the plane of motion defined by the conveying device. Rollers, said rotatable rollers for providing a recess in the conveying device. The vibratory rollers exert a vibratory action on the wood so that the bark and bark balls entangled in the wood fall either directly between the rollers and then further onto a conveyor etc. at a lower level, or into the recesses contained in the inventive device. Into the part, then through the relative movement of the rollers from between the rollers to fall onto the bark conveying device etc.

Such vibratory rollers, which deliver vertical impact from below to the tree currently being treated, have proven to be effective in most cases where it is desired to drop the bark from the top of the tree onto the roller unit and further from between the rollers onto the bark conveying unit Effective. However, during the treatment of the most difficult barks, especially very tough, strong and long barks, it is not possible to remove all of the bark with this roller arrangement, since some of the bark is at least partially wrapped around the tree and wedges Between the trees or between the tree and the roller device, the roller device cannot pull this bark through itself onto the bark conveyor below.

Contents of the invention

It is an object of the present invention to provide a method and a device that improve the debarking roller by allowing the bark to be removed to fall onto the roller arrangement more definitely than before and to travel at least temporarily without constraining the roller arrangement and without trees hindering its movement. The operational properties of the device, whereby the various components included in the roller device are able to pull the bark and drop it onto the bark conveying device below.

This object is achieved by a method according to the characterizing part of claim 1 and a pick-up roller according to the characterizing part of claim 2 .

The lifting movement included in the method refers to the action of lifting the tree in such a way that in the picking position the tree will temporarily reach a height of 100-500 mm above the conveying surface. Thus, the present method differs significantly from shaking or vibration of the prior art in which the tree is raised no more than a few centimeters. By means of this lifting movement, and its combined lateral movement and rolling about the longitudinal axis of the tree, the bark falls from the top of the tree onto the roller arrangement more efficiently than before, or, in any case, is temporarily Release to allow the roller arrangement to pull the bark through the roller arrangement onto the conveyor below.

The combined lifting movement, lateral movement and rolling in the method of the invention is preferably realized by the pick-up roller of the invention. The lifting motion is performed by means of the height-increasing portion of the lifting blade while rolling the tree. The lateral movement is achieved by means of the helix generated by the top surface of the height-increasing portion of the lifting blade as the pick-up roller rotates.

In a preferred embodiment of the invention, the lifting movement is achieved not only by means of a forced movement caused by the height-increasing portion of the lifting blade, but also by means of a throwing movement caused by the rotation of the lifting blade. The speed of rotation of the lifting blades can be adjusted to easily control the force of the throwing motion. Thus, the currently processed wood and bark are temporarily separated from each other as much as possible, and the debarking roller device can transfer the bark as easily and efficiently as possible to the conveyor device arranged below the roller device.

Rolling around the longitudinal axis of the tree is most efficiently produced in such a way that the height-increasing portion of the top surface of the lifting blade is at least largely configured according to an Archimedean spiral. Rolling works well for bark falling from the top of the tree.

The handing of the helix of the lifting blade located in the middle part of the pick-up roller is preferably chosen taking into account that the lifting blade conveys the tree from the middle part of the pick-up roller towards the end of the pick-up roller. Accordingly, the handing of the helix of the lifting blades at the ends of the pick-up rollers is preferably chosen taking into account that the lifting blades convey the tree from the ends of the pickup rollers towards the middle part of the pickup rollers. With this configuration, the relative distance between adjacent trees can be temporarily increased to allow bark to fall easily onto the roller arrangement.

The distance between two successive pick-up rollers is preferably greater than the average length of the trees currently being processed. This reduces the stress on the pick-up rollers, since the entire weight of the wood will not fall on a single pick-up roller, but the weight-induced load will be distributed at least between the pick-up roller and a specific roller in the roller arrangement.

The skinning roller device is preferably provided with a return movement. By means of this reciprocating movement, trees can be processed back and forth on the roller device in order to remove even the most difficult bark.

The width of the debarking roller arrangement is preferably chosen in consideration of providing enough space for the tree being processed to be fed in a single layer. This helps to provide a channel between the trees through which the bark falls onto the roller arrangement.

Description of drawings

The present invention will be described in detail below with reference to accompanying drawing, in accompanying drawing:

Fig. 1 shows the pick-up roller of the present invention;

Fig. 2 schematically shows a peeling roller device provided with a pick-up roller of the present invention in a plan view;

FIG. 3 shows a section along line III-III in FIG. 2 .

Detailed ways

Figures 2 and 3 show a debarking roller arrangement generally denoted by reference numeral 1, and Figure 1 shows a pick-up roller denoted by reference numeral 6 for improving the operability of such a debarking roller arrangement 1. The salient feature essential to the invention is that a debarking roller arrangement of a type known per se is provided with one or more pick-up rollers as shown in FIG. 1 .

The debarking roller device 1 is used to remove bark 2 from a wood flow traveling in the transverse direction of the rollers 3 of the roller device, ie in the direction of arrow A, and to accommodate the tree 5 and the bark 2 stripped from the tree. The stream of wood supported by the rollers 3 travels in a channel whose bottom is formed by the rollers. Each roller 3 is mounted by bearings for rotation about an axis of rotation 4 and is provided with drive means (not shown). The rollers 3 have a relative spacing in the feed direction of the roller arrangement (direction of arrow A), which is chosen in view of allowing the bark 2 to fall between the rollers. The roller means may comprise various types of rollers (not shown) to cause the bark 2 to be rolled up between the rollers and from which the bark falls onto a conveying device (not shown) below.

The presently discussed debarking roller device 1 comprising at least one pick-up roller 6 is used in particular for handling difficult bark 2 . These barks include, for example, that of certain eucalyptus trees stripped in long strips. The problem is that the bark 2 is at least partially wrapped around the trees 5 and wedged between the trees or between the trees and the roller arrangement. In this case, conventional debarking roller arrangements are not always able to guide and pull the bark from between the rollers of the roller arrangement to the conveyor below.

In order to eliminate these problems, the tree 5 is subjected to a combined lifting movement, lateral movement and rolling around the longitudinal axis of the tree 5 at least at one position of the debarking roller device 1, so that the tree currently at said at least one position is at least temporarily And at least partially separated from the debarking roller arrangement 1 and other trees 5 currently on the roller arrangement.

In practice, this is achieved by means of pick-up rollers 6 included in the debarking roller arrangement 1 .

The pick-up roller 6 is provided with its own drive which rotates the pick-up roller in the direction of arrow C. In other words, the operation of the pickup roller 6 can be controlled independently of the rotational speed of the roller 3 . The pick-up roller 6 comprises a rotatable central part 7 provided with at least one lifting blade 8 on the outer surface of the central part. The top surface 9 of the lifting blade 8 is configured in a helix and is provided with a height-increasing portion 10 and a height-decreasing portion 11 ( FIG. 3 ). The height-increasing portion 10 is adapted to start from or below the conveying surface 12 of the debarking roller device 1 and the height-decreasing portion 11 is adapted to extend to or below the conveying surface of the debarking roller device.

A pick-up roller 6 is installed in the debarking roller device 1 instead of one of the rollers 3 . The highest point of the central part 7 is therefore not higher than the conveying surface 12 established by the rollers 3 .

Once on (over, in line with) the pick-up roller 6, the tree 5 is adapted to be lifted by the action of the lifting blade 8 to a height of 100-500 mm above the conveying surface 12. This can be achieved by means of a forced movement caused by the height-increasing portion 10 of the lifting blade 8 . However, as far as the operation of the skinning roller device 1 is concerned, this effect is more preferably achieved by means of a combination of a forced movement caused by the height-increasing portion 10 of the lifting blade 8 and a throwing movement caused by the rotation of the lifting blade 8 .

In order to provide a suitable throwing motion, the pick-up roller 6 is adapted to be adjustable in its speed of rotation.

The height-increasing portion 10 of the top surface 9 of the lifting blade 8 is at least mostly configured as an Archimedes spiral, so as to effectively give the tree a rolling and throwing motion simultaneously. An Archimedes spiral is a curve generated by a point moving at a uniform velocity along a radius of uniform rotation.

The helix of the lifting blades 8 located in the middle part of the pick-up roller 6 is chosen to have such a hand direction that when the pick-up roller 6 rotates, the trees 5 are conveyed by the lifting blades 8 from the middle part of the pick-up roller 6 towards its ends. On the other hand, the helix of the lifting blades 8 located at the ends of the pick-up roller 6 is chosen to have such a hand direction that when the pick-up roller 6 rotates, the trees 5 pass through the lifting blades 8 from the end of the pick-up roller 6 toward the pick-up roller. The middle part of the roller is conveyed.

In order to limit the stresses exerted on the pick-up rollers 6, the distance between two successive pick-up rollers 6 is greater than the average length of the tree 5 currently being processed.

The debarking roller unit 1 is provided with a reciprocating movement, in other words, the roller 3 can either rotate in the direction of the arrow D for the actual feeding movement, or it can rotate in the opposite direction, and the roller unit can process the tree back and forth until the bark is completely removed.

The width B of the debarking roller device 1 is chosen such that the tree 5 currently being processed has enough space to be fed in a single layer.

Claims (12)

1. method that is used to improve the operating characteristics of peeling rollers device (1), described roller arrangement is suitable for the bark (2) removing bark (2) and hold trees (5) and peel off from trees from the wood flow of advancing along the horizontal direction of the roller (3) of roller arrangement, and make bark (2) be wrapped at least in part trees (5) on every side and wedge between the trees or trees and roller arrangement between, it is characterized in that, at least in a position of peeling rollers device (1), the lifter motion that trees (5) make up, be displaced sideways and around the rolling of the longitudinal axis of trees (5), so that make current trees in described at least one position separate at least temporarily and at least in part with peeling rollers device (1) and current other trees (5) on roller arrangement.

2. pick-up roller (6) that is included in the peeling rollers device (1) with the operating characteristics that is used to improve this roller arrangement, described roller arrangement is suitable for the bark (2) removing bark (2) and hold trees (5) and peel off from trees from the wood flow of advancing along the horizontal direction of the roller (3) of roller arrangement, and making bark (2) be wrapped in trees (5) at least in part goes up and wedges between the trees or between trees and the roller arrangement, it is characterized in that, pick-up roller (6) comprises a rotatable central module (7), the case surface of this central module is provided with at least one and promotes blade (8), and the end face of this blade (9) is according to the helix structure and be provided with highly increase part (10) and height minus fraction (11); Highly increase part (10) and be suitable for from the conveyor surface (12) of peeling rollers device (1) or this below conveyor surface, height minus fraction (11) is suitable for extending to peeling rollers device delivery face or this is below conveyor surface; Described peeling rollers device (1) is provided with one or more pick-up rollers (6).

3. pick-up roller according to claim 2 is characterized in that, in case arrive pick-up roller (6), trees (5) are adapted to pass through the height that the action that promotes blade (8) is thus lifted to conveyor surface (12) top 100-500mm.

4. pick-up roller according to claim 2 is characterized in that, the hoisting depth that arrives the trees (5) of pick-up roller (6) is suitable for realizing by means of the positive motion that is caused by highly increase part (10).

5. pick-up roller according to claim 2, it is characterized in that the hoisting depth that arrives the trees (5) of pick-up roller (6) is suitable for realizing by means of the positive motion that is caused by highly increase part (10) with by the motion of dishing out that the rotation that promotes blade (8) causes.

6. pick-up roller according to claim 2 is characterized in that, the rotary speed of pick-up roller (6) can be regulated.

7. pick-up roller according to claim 2 is characterized in that, the height increase part (10) of the end face (9) of lifting blade (8) is most of at least constructs according to Archimedes spiral.

8. pick-up roller according to claim 2, it is characterized in that, the helix of lifting blade (8) that is positioned at the mid portion of pick-up roller (6) is chosen as has such rotation direction, promptly makes trees (5) carry towards its end from the mid portion of pick-up roller (6) by promoting blade (8).

9. pick-up roller according to claim 2, it is characterized in that, the helix of lifting blade (8) that is positioned at the end of pick-up roller (6) is chosen as has such rotation direction, promptly makes trees (5) carry towards the mid portion of this pick-up roller from the end of pick-up roller (6) by promoting blade (8).

10. pick-up roller according to claim 2 is characterized in that, the distance between two pick-up rollers (6) in succession is greater than the average length when the trees (5) of pre-treatment.

11. pick-up roller according to claim 2 is characterized in that, peeling rollers device (1) is provided with return motion.

12. pick-up roller according to claim 2 is characterized in that, the width (B) of peeling rollers device (1) is chosen as, and makes the trees (5) of working as pre-treatment enough spaces be arranged so that with independent one deck feeding.

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