Roller assembly, toothed segment stack for a roller assembly, toothed segment for a toothed segment stack

Abstract

Roller assembly (1) for a wood processing plant, comprising a roller body (2) which is intended to be driven for a rotational movement of the roller assembly (1), and comprising a plurality of toothed segments (7), each comprising a plurality of toothed elements (8) which are intended to come into contact with a tree trunk during a rotational movement of the roller assembly (1), wherein at least two toothed segments (7) are detachably connected to one another and at least partially form a toothed segment stack (6), and the toothed segment stack (6) is detachably arranged on an outer circumferential side of the roller body (2)

Description

[0001] The invention relates to a roller assembly, a toothed segment stack for a roller assembly, a toothed segment for a toothed segment stack and methods for assembling and repairing a roller assembly.

[0002] In industrial wood processing, driven rollers are often used to impart a feed motion to a log being processed, for example, so that it can be transported to various processing stations and processed into boards or similar products. For this purpose, the rollers are each set in a rotating motion and come into contact with the log on their outer circumferential surfaces. To simplify the generation of the feed motion, the outer circumferential surface of such a roller can be covered with profile elements.

[0003] The rollers described above are advantageous because they can usually be designed as comparatively simple, one-piece components, which leads to high operational reliability. However, unavoidable wear and tear occurs on the outer peripheral surfaces, typically requiring replacement of the entire roller. This is associated with high resource consumption and, on the other hand, considerable disassembly effort, especially since the roller must be separated from the drive components of the affected wood processing plant.

[0004] The invention is therefore based on the object of proposing means by means of which the above-mentioned disadvantages can be overcome.

[0005] The object is achieved by means of a roller assembly according to claim 1, a toothed segment stack according to claim 12, a toothed segment according to claim 13, a method for assembling a roller assembly according to claim 14 and a method for repairing a roller assembly according to claim 15. Advantageous further developments are the subject matter of dependent subclaims.

[0006] The roller assembly according to the invention is intended for use in a wood processing plant and comprises a roller body which is provided to be driven for a rotational movement of the roller assembly. The roller assembly further comprises a plurality of toothed segments, each comprising a plurality of toothed elements. The toothed segments are provided to come into contact with a tree trunk during the rotational movement of the roller assembly. At least two of the toothed segments are detachably connected to one another and form a toothed segment stack or part of a toothed segment stack. This toothed segment stack is detachably arranged on an outer circumferential side of the roller body.

[0007] One advantage of the roller assembly according to the invention is that it has toothed segments that are separate from the roller body and can be replaced as needed as soon as signs of wear appear. In particular, it is therefore not necessary to replace the entire roller assembly, but only the affected toothed segments, which leads to reduced resource requirements. However, the replacement does not take place by dismantling individual toothed segments, but rather one or more toothed segment stacks. This aspect of the invention is based on the realization that individual tooth elements are rarely affected by signs of wear or damage, so that usually several adjacent tooth elements are affected. The dismantling and replacement of entire toothed segment stacks therefore results in advantages with regard to the handling of the components of the roller assembly to be replaced, which means that the overall dismantling and assembly effort is low.

[0008] Within the scope of the invention, the roller body can be regarded as a substantially rotationally symmetrical component or assembly, which preferably has a mechanical interface for connecting to at least one drive component of a wood processing system. The roller body is preferably designed as a cylindrical sleeve, in the interior of which the roller body can be mechanically coupled to the drive component. The roller body is preferably made of metal, in particular steel. On its outer circumferential side, the roller body can have an at least partially smooth and / or profiled surface and / or mechanical interfaces for receiving the tooth segment stacks, for example by means of a positive and / or non-positive connection.It is within the scope of the invention that the roller body and thus the entire assembly is mounted with its axis of rotation vertically in order to generate a translational movement of the tree trunk or, in comparison, is inclined in order to generate a rotational movement of the tree trunk about its trunk axis in addition to the translational movement.

[0009] A toothed segment can have a curved base body that has an arcuate profile in a plane. The plurality of tooth elements can be arranged on a convex outer side. On a concave inner side, the toothed segment can correspond, at least in regions, to the outer circumferential side of the roller body. At the end faces, the toothed segments can be essentially flat in order to be brought into flush, full-surface contact with one another. It is also within the scope of the invention for the toothed segments to have mutually corresponding form-locking elements on their end faces in order to be able to be centered relative to one another to create a toothed segment stack.

[0010] The invention is fundamentally not limited to the geometry of the tooth elements. In a simple embodiment, the tooth elements are at least partially triangular in cross-section and are arranged in particular evenly distributed on the tooth segment, in particular on its convex outer side. A tip of such a tooth element points away from the roller assembly when mounted on the roller body and preferably serves to engage with or penetrate the surface of the tree trunk in order to convert the rotational movement of the roller assembly into a feed movement of the tree trunk. It is also within the scope of the invention for the tooth elements to be rectangular or square in shape, at least in certain regions.

[0011] A tooth segment stack according to the invention is formed by at least two tooth segments. Preferably, the tooth segment stacks are

[0012] Tooth segment stacks are joined by being releasably clamped together, in particular axially clamped together with respect to a rotational axis of the roller assembly. It is conceivable that the tooth segments are only clamped together as a result of their assembly on the roller body. In this case, they can previously be spatially bundled as a tooth segment stack, which is arranged on the roller body before they are clamped together to form the tooth segment stack. However, it is particularly advantageous if the tooth segments are pre-assembled to form the tooth segment stack and clamped together in a state detached from the roller assembly. This enables easy exchange of the tooth segment stack on the roller assembly, as already explained above.

[0013] The tooth segments can be centered relative to one another by means of a clamping element and clamped along a longitudinal axis of the clamping element. In particular, the clamping element can be a clamping sleeve or a tension rod by means of which the tooth segments are centered. It is conceivable for a first tooth segment arranged at the edge to exert a first clamping force against the remaining tooth segments of the tooth segment stack by means of a screw head of a clamping screw which engages with the clamping element. A clamping screw or a comparable clamping element can also be arranged on an opposite side of the tooth segment stack, which exerts a second clamping force against a second tooth segment arranged at the edge.Alternatively, the clamping element on the opposite side of the tooth segment stack can also be directly connected to a tooth segment arranged on the edge, so that the clamping force can be exerted by means of a single clamping screw.

[0014] Preferably, a plurality of tooth segment stacks are arranged distributed on the outer circumferential side of the roller body. This aspect of the invention is based on the finding that a distributed arrangement of tooth segment stacks on the outer circumferential side of the roller body promotes the interchangeability of the tooth segments. Studies have shown that a number of at least two, but preferably three, tooth segment stacks, which cover the entire outer circumferential side of the roller body, is particularly advantageous. This is fundamentally related to the fact that the tooth segment stacks, which each cover only part of the outer circumferential side of the roller body, have a significantly lower weight than, for example, a structure in which the tooth elements are formed continuously to cover the entire outer circumference of the roller body.In addition, by dividing the roller into multiple tooth segment stacks, it is possible to arrange these radially on the roller body, eliminating the need to disassemble the roller body to replace the tooth segments. It is within the scope of the invention that a total of four, five, six, seven, or eight tooth segment stacks can be distributed around the outer circumference of the roller body. Such a small number of tooth segment stacks results in particularly low assembly and repair costs for the roller assembly and promotes the stability of the tooth segment stacks, as they can be designed to be comparatively wide in the circumferential direction.

[0015] In an advantageous further development, the roller body is positively connected to the tooth segment stack on the outer peripheral side by means of at least one key.

[0016] Within the scope of the invention, the feather key can be regarded as a force-transmitting element which is intended to transmit the rotational movement of the roller body to the toothed segments or toothed segment stack arranged on the outer circumference, or vice versa. In particular, the feather key is designed to transmit a force and / or movement from the roller body to the toothed segment stack and / or vice versa, preferably only in a tangential direction with respect to the rotational movement of the roller assembly. For this purpose, the feather key can be arranged in a feather key groove of the roller body, which is formed on the outer circumference of the roller body. The feather key and / or the feather key groove can each be elongated and preferably have a length which essentially corresponds to the height of the roller body.Preferably, the key can be arranged detachably in the keyway, preferably by means of a press fit and / or by means of a screw connection.

[0017] In an advantageous further development, the roller assembly has a flange element which is arranged in a frontal region of the roller body and is connected to the roller body.

[0018] The flange element can serve as an axial stop element, allowing a toothed segment stack to be aligned along the longitudinal axis of the roller body during assembly. This particularly simplifies the replacement of a toothed segment stack.

[0019] The flange element preferably comprises a gear ring. This allows for a high degree of functional integration, since the flange element can serve as an axial stop element, as already explained above, but can also be provided with a plurality of toothed elements that can come into contact with the tree trunk. It is within the scope of the advantageous development that the flange element is clamped to the toothed segment stack or merely serves as an axial support.

[0020] It is within the scope of the advantageous development that the flange element and / or the gear ring can be detachably connected to the roller body. However, since the frontal area of ​​the roller assembly is less susceptible to damage or wear during normal operation than a centrally located axial section, it is also conceivable that the flange element and / or the gear ring can be permanently connected to the roller body.

[0021] Preferably, at least two tooth segments of the tooth segment stack are designed differently, in particular in a number and / or geometry and / or arrangement of their tooth elements.

[0022] Typically, logs are transported essentially along the trunk axis, resting on a conveyor chain or similar support, while the roller assembly is positioned laterally to the log. Since logs generally have an at least approximately circular cross-section due to their natural growth, the roller assembly does not come into contact with the log on the outside over its entire height, but rather in an axial section. Depending on the variation in the diameter of the logs being conveyed, several different axial sections may arise in which a roller assembly comes into contact with the logs.Since the masses of the tree trunks also vary with varying diameters, it may be advantageous to design the toothed segments of the roller assembly differently in order to ensure reliable transport even with fluctuating trunk dimensions. In particular, the toothed elements of a first toothed segment in a first axial section of the roller assembly can have a pitch and / or tooth size that differs from the toothed elements of a second toothed segment in a second axial section of the roller assembly.

[0023] In an advantageous development, a holding element is arranged between two adjacent tooth segment stacks, by means of which the two adjacent tooth segment stacks are radially fastened, in particular clamped, to the roller body. This makes it possible to fix the tooth segment stacks to the roller assembly. In combination with a feather key arranged between the roller body and one of the tooth segment stacks, the holding element can be dimensioned to exert a radially directed holding force on the tooth segment stacks, while the feather key connection is dimensioned to transmit a force tangentially directed with respect to the rotational movement from the roller body to the tooth segment stack and / or vice versa. This allows a high degree of functional separation to be achieved, whereby the feather key and the holding element can each be easily dimensioned and designed.The retaining element preferably has at least one toothed element on a side facing away from the roller body. This allows the entire outer circumference of the roller assembly to be covered with toothed elements. In particular, the retaining element is a clamping element by means of which two adjacent toothed segment stacks are attached to the roller body. The clamping element and at least one of the toothed segments can be positively connected to one another.

[0024] In an advantageous further development, a tooth segment has two edge regions and an intermediate core region, wherein the mechanical rigidity in at least one of the edge regions is lower than in the core region.

[0025] According to the development described above, the tooth segments of a tooth segment stack can be positioned with their core areas on the outer circumferential side of the roller body and fastened to the roller assembly at the edge areas, for example by means of the holding element described above. In this case, it is not necessary for all tooth segments to lie flush against the outer circumferential side of the roller body immediately upon application of the tooth segment stack. Rather, flush contact can only be established as a result of fastening, by pressing the edge areas of the tooth segments against the roller body, preferably by means of the holding element. Overall, the different stiffnesses result in an advantageous stress distribution in the roller assembly and in particular in the tooth segments or the tooth segment stack.

[0026] The differences in stiffness between the edge areas and the core area of ​​a toothed segment can be adjusted in various ways. It is also advantageous if the toothed segment is provided with a groove in the edge area on a side facing away from the toothed segments. This allows the stiffness to be reduced in a simple design.

[0027] In an advantageous further development, the tooth segment stack has at least one intermediate segment which is arranged between two tooth segments.

[0028] Investigations by the applicant have shown that it is advantageous if the roller assembly is not continuously covered with toothed elements across its entire height. Rather, toothed elements spaced apart along the rotational axis of the roller assembly can better penetrate the surface of the log to impart a transport movement. Furthermore, a gap between the toothed elements of two adjacent toothed segments prevents unwanted rotational movement of the log during its feed movement.

[0029] Preferably, the tooth segments and the intermediate segment are made of different materials. In particular, it has proven advantageous to construct the tooth segments from metal and the intermediate segment from plastic. This improves the detachability of the tooth segments of a tooth segment stack. This is due, among other things, to the fact that direct contact between two metallic tooth segments can lead to a mechanical connection between the tooth segments due to corrosion. In comparison, a plastic intermediate segment and a metal tooth segment tend not to react with each other, or to a significantly lesser extent.

[0030] In an advantageous further development, the tooth segment is manufactured by laser cutting.

[0031] Laser cutting offers several advantages in the production of gear segments. The precision of the laser beam enables particularly accurate cuts, as the gear segments are subject to only minimal thermal influence. In particular, the gear segments can be manufactured with deviations in the range of ± 0.1 mm to ± 1 mm. Furthermore, the gear segments can be manufactured essentially burr-free, which eliminates the need for subsequent post-processing.

[0032] As mentioned above, the object of the invention is also achieved by means of a toothed segment stack for the roller assembly according to the invention or an advantageous development thereof, as well as by a toothed segment for such a toothed segment stack. With regard to the conceivable configurations of the toothed segment stack or the toothed segment and the advantages achievable thereby, the statements regarding the roller assembly and its advantageous developments apply accordingly.

[0033] The object is further achieved by a method for assembling a roller assembly. According to the invention, a plurality of toothed segments are provided, each comprising a plurality of toothed elements designed to come into contact with a tree trunk during a rotational movement of the assembled roller assembly. At least two toothed segments are clamped together to form a toothed segment stack. Furthermore, a roller body is provided, on the outer circumferential side of which the toothed segment stack is detachably arranged.

[0034] In particular, the method according to the invention is used to assemble the roller assembly according to the invention or an advantageous development thereof. At least in this respect, the method enables a particularly simple assembly of a roller assembly, and the above statements regarding the roller assembly according to the invention and its advantageous developments apply accordingly.

[0035] The object is also achieved by a method for repairing a roller assembly, in which a roller assembly is provided which comprises a roller body which is intended to be driven for a rotational movement of the roller assembly, and with a plurality of toothed segments, each comprising a plurality of tooth elements which are intended to come into contact with a tree trunk during a rotational movement of the roller assembly. At least two toothed segments are clamped to form a toothed segment stack, and the toothed segment stack is detachably arranged on an outer circumferential side of the roller body. For a repair, a toothed segment stack is detached from the roller assembly and replaced with another toothed segment stack.

[0036] In particular, the method according to the invention serves to repair a roller assembly according to the invention or an advantageous development thereof. In this respect, the method serves to particularly easily replace tooth segment stacks that exhibit signs of wear or damage as a result of use of the roller assembly.

[0037] Advantages of the invention are explained below using embodiments and the figures.

[0038] It shows Figure 1 shows a roller assembly; Figure 2 shows an exploded view of a roller assembly; Figure 3 shows a tooth segment stack with a plurality of tooth segments.

[0039] In industrial wood processing, it is often necessary to move a log forward. This typically involves simple, one-piece rollers that rotate and come into contact with the log on their outer circumference to move it.

[0040] For improved power transmission to generate the log's feed motion, the roller can be offset with profile elements on the outer circumference, which, however, can wear out as a result of roller operation. In such a case, the roller must usually be completely replaced with an intact roller, which usually involves a high installation effort at the affected wood processing plant and a high expenditure of resources. To reduce these disadvantages, the Figure 1The roller assembly 1 shown has a structure with which it is possible, if necessary, to replace damaged components arranged on the outer circumference in a simple manner.

[0041] The roller assembly 1 comprises a roller body 2, which is designed to be set into a rotational movement about a rotation axis 3 by means of a drive. The roller body 2 is designed as a substantially rotationally symmetrical hollow cylinder, on the outside of which three keyways 4 are arranged, of which only one keyway 4 is provided with a reference symbol. The rotational movement is transmitted to several tooth segment stacks 6 arranged on the outside via three corresponding keys 5.

[0042] Overall, the Figure 1The roller assembly 1 shown has three toothed segment stacks 6, of which only one toothed segment stack 6 is provided with a reference symbol for clarity. Each toothed segment stack 6 has a plurality of toothed segments 7, of which only one toothed segment is also provided with a reference symbol.

[0043] The toothed segments 7 are each metal components manufactured by laser cutting and serve to transmit the rotational movement of the roller assembly 1 to a tree trunk. For this purpose, the toothed segments 7 each have a plurality of toothed elements 8, which are designed to come into contact with and partially penetrate a tree trunk surface in order to generate the feed movement of the tree trunk as a result of the rotation of the roller assembly.

[0044] A particular advantage of the roller assembly according to Figure 1is that the tooth segment stacks 6 are arranged distributed around the outer circumference of the roller body 2. In the event that the tooth segments 7 or a tooth element 8 arranged thereon becomes damaged, the tooth segment stacks 6 can be easily replaced by being dismantled from the roller body 2 in the radial direction. Subsequently, a pre-assembled tooth segment stack 6 can be attached to the roller body 2 in place of the dismantled tooth segment stack 6, also in the radial direction, and fixed thereto. It is not absolutely necessary to dismantle the roller body 2. Rather, it can remain mounted on the wood processing plant throughout the entire assembly or repair process.

[0045] Instead of replacing the entire tooth segment stack, only the damaged tooth segment 7 on the dismantled tooth segment stack 6 can be replaced so that it can be arranged again on the roller body 2.

[0046] The interchangeability of individual tooth segment stacks 6 is facilitated by the fact that the tooth segments 7 of the tooth segment stacks 6 are axially clamped together. As a result, the tooth segments 7 are present as a spatially bundled tooth segment stack 6 even when disassembled.

[0047] As shown by Figure 3 As will be explained in detail, two tension rods 12 (see Figure 3 ) to center the tooth segments 6 and to clamp them via the tooth segments 6 located on the edge.

[0048] For easy assembly, the roller assembly 1 has a flange element 9 with a rotating gear ring, which is arranged on one end face of the roller body 2 and is not structurally connected to the toothed segment stacks 6. Rather, the flange element 9 serves as an axial stop element during assembly of the toothed segment stacks 6 to the roller body 2. At the same time, the gear ring serves to generate the desired movement of the tree trunk.

[0049] The roller assembly 1 has three clamping elements 10, only one of which is provided with a reference symbol. Each of the clamping elements 10 serves to radially connect two adjacent tooth segment stacks 6 to the roller body 2. This allows a detachable connection to be easily formed, which facilitates the replacement of individual tooth segment stacks 6.

[0050] Each of the toothed segments 7 has two peripheral edge regions with respect to the rotation axis 3, as well as a core region located therebetween. To prevent excessive tensioning of individual toothed segments 6 during assembly of the toothed segment stacks 7 using the clamping elements 10, these have a lower rigidity in the peripheral regions than in the core region. This is achieved by means of a groove 11, which allows deformation of the toothed segments 6 when the toothed segment stacks 7 are fastened to the roller body 2 using a clamping element 10. This also enables a predominantly flush fit of the toothed segment stacks 6 on the outer peripheral side of the roller assembly 2.

[0051] Figure 2 shows the roller assembly 1 according to Figure 1 in exploded view. As in Figure 2As can be seen in particular, the flange element 9 with the externally arranged toothed ring is not part of the detachable tooth segment stack 6, but is connected to the roller body 2. Otherwise, however, the statements regarding Figure 1 accordingly.

[0052] Figure 3 shows a tooth segment stack 6, which in relation to the Figure 1 and 2 has already been described. As can be seen from Figure 3 As can be seen, two tension rods 12, of which only one tension rod is shown in section and provided with a reference symbol, extend through the tooth segment stack 6. The tension rods 12 are connected at one end to a support element 13. The assembly of the tension rods 12 and the support element 13 can serve as an assembly aid in the disassembled state of the roller assembly, wherein the tooth segments 7 can be positioned along the tension rods 12 and can be clamped to the tooth segment stack 6 via a clamping screw.

[0053] As shown by Figure 3 As also shown, the tooth segment stack 6 comprises not only a plurality of tooth segments 7, but also a plurality of spacers 14, each arranged between two adjacent tooth segments 7. The spacers 14 serve to create regular spacing between the tooth segments 7 and the tooth elements 8 in the axial direction. This improves the penetration behavior of the tooth elements 8 into the surface of a tree trunk to be transported.

Claims

1. Roller assembly (1) for a wood processing plant with a roller body (2) which is intended to be driven for a rotational movement of the roller assembly (1), and with a plurality of toothed segments (7), each comprising a plurality of toothed elements (8) which are intended to come into contact with a tree trunk during a rotational movement of the roller assembly (1), wherein at least two toothed segments (7) are detachably connected to one another and at least partially form a toothed segment stack (6), and the toothed segment stack (6) is detachably arranged on an outer circumferential side of the roller body (2).

2. Roller assembly according to claim 1, wherein the at least two toothed segments (7) are clamped together, in particular axially with respect to a rotational axis of the roller assembly.

3. Roller assembly (1) according to claim 1 or 2, wherein the roller body (2) is positively connected to the tooth segment stack (6) on the outer peripheral side by means of a key (5).

4. Roller assembly (1) according to one of claims 1 to 3, with a flange element (9) which is arranged in an end region of the roller body (2) and is connected to the roller body (2).

5. Roller assembly (1) according to claim 4, wherein the flange element (9) comprises a toothed ring.

6. Roller assembly (1) according to one of claims 1 to 5, with a plurality of tooth segment stacks (6), in particular three tooth segment stacks (6), which are arranged distributed on the outer circumferential side of the roller body (2).

7. Roller assembly (1) according to one of claims 1 to 6, in which at least two tooth segments (7) of the tooth segment stack (6) are designed differently, in particular wherein the tooth elements (8) of a first tooth segment (7) in a first axial section of the tooth segment stack (6) have a number and / or geometry and / or arrangement which differ from a number and / or geometry and / or arrangement of the tooth elements (8) of a second tooth segment in a second axial section.

8. Roller assembly (1) at least according to claim 6, wherein a holding element (10) is arranged between two adjacent tooth segment stacks (6), by means of which holding element the two adjacent tooth segment stacks (6) are radially fastened, in particular clamped, to the roller body (2).

9. Roller assembly (1) according to one of the preceding claims, in which at least one toothed segment (7) has two edge regions and an intermediate core region and the toothed segment (7) is designed such that the mechanical rigidity in at least one of the edge regions is lower than in the core region.

10. Roller assembly (1) according to claim 9, wherein the toothed segment (7) has a groove (11) in the edge region on a side facing away from the toothed elements (8).

11. Roller assembly (1) according to one of the preceding claims, in which the tooth segment stack (6) has at least one intermediate segment (14) which is arranged between two tooth segments (7), wherein the intermediate segment (14) is made in particular from a different material than the tooth segments (7), wherein in particular the intermediate segment (14) is made from plastic and the tooth segments (7) are each made from metal.

12. Roller assembly (1) according to one of the preceding claims, wherein the toothed segment (7) is manufactured by laser cutting.

13. Tooth segment stack (6) for a roller assembly (1) according to one of claims 1 to 12.

14. Toothed segment (7) for a toothed segment stack (6) according to claim 13.

15. A method for assembling a roller assembly (1), in particular a roller assembly (1) according to one of claims 1 to 12, in which a plurality of toothed segments (7) are provided, each comprising a plurality of toothed elements (8) which are intended to come into contact with a tree trunk during a rotational movement of the assembled roller assembly (1), and at least two toothed segments (7) are detachably joined to form a toothed segment stack (6), and in which a roller body (2) is provided, on the outer circumferential side of which the toothed segment stack (6) is detachably arranged.

16. A method for repairing a roller assembly (1), in particular a roller assembly (1) according to one of claims 1 to 12, wherein the roller assembly (1) is provided which comprises a roller body (2) which is intended to be driven for a rotational movement of the roller assembly (1), and with a plurality of toothed segments (7), each comprising a plurality of tooth elements (8) which are intended to come into contact with a tree trunk during a rotational movement of the roller assembly (1), wherein at least two toothed segments (7) are detachably joined to form a toothed segment stack (6) and the toothed segment stack (6) is detachably arranged on an outer circumferential side of the roller body (1), wherein one toothed segment stack (6) is detached from the roller assembly (1) and replaced by another toothed segment stack (6).

Images