FI80511C - Support structure for a rotating drum - Google Patents

Description

1 80511

The present invention relates to a rotating drum support structure comprising an endless chain or track formed by support rollers, wherein the support rollers involved in drum support below the drum are supported in a path below the rollers, and there is a mechanism . The support structure is particularly suitable for supporting a drum for debarking trees. 10 It can also be used to support other drums where high forces are applied to the support structure, e.g. to support the drum of a drum shell press.

A bark drum is commonly used to separate the bark from the tree trunks. The support of the drum has previously been implemented with two wheels of the tu-15 or with wheels formed by two wheels. Chains attached to the chain are also used, in which case the ends of the chain are suspended on a support structure above the drum (e.g. SE publication 405 330), or an endless suspension chain rotates around the support wheel-20 above the drum. Hydrostatic bearings are also known. In this case, several circumferential bearings (e.g. SE patent publication 345 072) or one bearing covering a longer arc can be used to support both ends of the drum.

However, these previously known structures have 25 mm. the following disadvantages. Due to the high weight of the drum filled with wooden trunks, the line pressure between the load-bearing member and the drum is also high, so that the structures break easily. They also require high manufacturing precision and are complex in construction. The problem with suspended chain solutions is that the links connecting the rollers of the chain tend to stretch due to the high loads applied to them.

U.S. Pat. No. 2,858,177 discloses a solution in which the drum is supported by endless roller chains below it. The roller chain is arranged to run around a guide member rotatable relative to the axis 35 of the drum. This swing guide member balances the loads on the rollers to some extent, but not enough.

The object of the present invention is to eliminate the above-mentioned drawbacks of these previously known solutions. The support structure according to the invention is mainly characterized in that the load-balancing mechanism is a flexible structure.

When the force in the structure according to the invention is distributed on the circumference of the drum at several points of cross-section, the force on a single load-bearing roller is reduced, which makes it possible to use simple materials. The force is made to be distributed almost equally among all the support rollers 10. When the rollers are supported from below and not by suspension, the loops connecting the rollers are not subjected to high tensile loads. Flexible support means that high dimensional accuracy is not required of the path, even if the path extends along the circumference of the drum into a long arc.

The invention and its details will be described in more detail below with reference to the accompanying schematic drawings, in which Fig. 1 shows a cross-section of a shell drum and a support structure according to the invention, Fig. 2 shows the same side view, Fig. 3 Da 25 Figure 5 shows another alternative.

The drum 1 is provided with support frames 2 and the drum is rotated about its horizontal axis by means of a drive ring 3 in a manner known per se. Below the support ring 2 there is an endless roller chain or track formed by rollers 4.

Below the rollers at the support frame there is a path 5 formed by an arc bent plate, which in turn is supported from below by a support structure 6 and a resilient layer 7 thereon. The support structure 6 is supported by supports 35 8 connected to the base 9 on the sides of the support structure.

As the drum 1 rotates, an endless roller chain or track rotates around the path 5, the support structure 6 and the flexible layer 7. An oil space il 3 80511 can be arranged at the lowest point of the chain orbit, whereby the rollers become lubricated as they pass through it. The actuators are also lubricated at the same time.

Figure 4 shows an embodiment in which the rollers 4 are connected at their ends to each other by loops 10 to endless chains.

However, it is not necessary to connect the rollers with loops. They can also be returned to the beginning of the path along the channel below the orbit shown in Fig. 1 also separated from each other. This channel revolves around the path 10 5, the flexible layer 7 and the support structure 6. The distance between the two axial walls of the rollers of the channel corresponds to the diameter of the roll, whereby the channel directs the rollers to run in parallel in the channel.

Adjacent rollers of the roller track may be attached to each other. Where the loads to be carried allow the number of load-receiving rollers to be reduced, the spacers 11 shown in Fig. 5 can be used between the rollers. These are slightly smaller in height than the diameter of the rollers and therefore do not participate in load support.

20 The number of rollers is chosen so that they, either alone or together with the spacers, fill the entire channel. Thus, the rollers moving from the path 5 to the channel below force the further rollers back along the part below the channel back to the beginning of the path 5.

The flexible layer 7 between the path 5 and the support structure 6 allows the rollers to be positioned in such a way that the support frame or support structure is not required to have very high dimensional and dimensional accuracy, although the support extends over a relatively long part of the support frame. The length of the arch of the supporting part can in practice be, for example, about 5 m.

When the weight of the drum is distributed at a time, e.g. to the 20 rollers of the chain, the force applied to each roller is only 1/5 of the force that would be applied to each wheel when four wheels are used on the same support ring. For different load needs, a different number of rollers participating in the support can be used. With the structure according to the invention, the total load of one roll is obtained, e.g. only about 20 tn. When using small rollers instead of larger wheels * 80511, the overall height of the support structure itself is also reduced.

When the chain or part of it wears out in use, it is easy to replace it in whole or in part, if necessary. Therefore, it does not need to be made of a very durable material.

The rollers can have a length of e.g. 300 ... 500 mm and a diameter of e.g. 100 ... 250 mm. For example, two roller chains per drum can be used, but more if necessary. It is also possible to use only one chain in the central section of the drum if suitable support members are used at the ends of the drum. In addition, suitable means for axial control of the drum can be provided.

The roller chain may rotate the support structure 6 instead of the underside of the drum over the top of the drum, the drum as long as the weight 15 is received beneath a support structure of the chain.

The layer 7 of flexible material may be a compressible material, e.g. polyurethane, or a deformable material, e.g. rubber. It can also be replaced by a pressurized gas or liquid between the plates 5 and 6. Metal springs can also be used.

Claims (8)

A support structure of a rotating drum (1) comprising an endless chain or track formed by support rollers (4), wherein the 5 support rollers (4) participating in the support of the drum (1) below the drum are supported in a path (5) below the rollers, and between the support structure (6) there is a mechanism (7) which equalizes the load on the rollers (4) between the rollers, characterized in that the load-balancing mechanism (7) has a flexible structure. Support structure according to Claim 2, characterized in that the flexible structure (7) is formed using a compressible or deformable substance, a gas or liquid under pressure or metal springs. Support structure according to Claim 1 or 2, characterized in that the support rollers (4) are connected to one another by loops (10). Support structure according to Claim 1 or 2, characterized in that the support rollers (4) are arranged loose on the support track. Support structure according to Claim 4, characterized in that the support rollers (4) are arranged on the support track in such a way that the successive support rollers are in contact with one another. 5 80511 Support structure according to Claim 4, characterized in that a spacer part (11) is arranged between each of two successive support rollers (4). Support structures according to one of Claims 4 to 6, characterized in that the support rollers are arranged in an endless channel, the distance between the two opposite walls per roll corresponding to the diameter of the rollers. Support structures according to one of Claims 1 to 7, characterized in that it is used in a bark drum for peeling wood or in a drum bark press for separating water from the bark material. 6 80511