1. Technical Field
The present disclosure in some embodiments generally relates to debarker apparatuses, and more specifically to debarker apparatuses having swing arm assemblies with replaceable inserts.
2. Description of the Related Art
Rotary log debarkers, commonly referred to as ring debarkers, are used to remove bark from logs to facilitate processing of the logs into lumber and other wood products. Rotary log debarkers often have an array of swing arms pivotally mounted to a rotatable outer ring. Each of the swing arms has a tip for scraping bark from the logs.
As a log moves along a processing line of a traditional debarker, the advancing log contacts and pushes against the leading edges of the swing arms carried by the rotating outer ring. The log then drives the swing arms outwardly until the tips of the swing arms engage the periphery of the log. In this manner, swing arms can be self-opened. Once opened, the swing arms are urged inwardly such that the tips scrape bark off the log. The tips often remove the bark in a somewhat spiral pattern.
Unfortunately, the leading edges of the swing arms may be damaged due to the applied loads (e.g., the axial loads produced when each of the logs strikes against the swing arms) and frictional interaction with the logs. After repeated use, the leading edges may become dull, blunt, roughened, or otherwise damaged such that undesirable large frictional forces are present when the leading edges contact the logs. These frictional forces can prevent proper self-opening of the swing arms and may also damage the ends of the logs. For example, roughened leading edges can scrape wood from the ends of the logs, thus reducing the amount of usable wood resulting in decreased lumber production.
To maintain proper self-opening and limit this unwanted damage to the logs, the leading edges of the swing arms are often repaired by building-up new leading edges. For example, material can be welded over a damaged leading edge to form a new leading edge. Unfortunately, because welding often creates irregular surfaces, it may be difficult to form a leading edge sufficiently smooth for consistent self-opening of the swing arms. Moreover, a lengthy welding process can result in significant machine downtime, thereby reducing lumber production. Other problems, such as induced residual stresses, reduced toughness (e.g., fracture toughness), and the like, are also associated with welding processes.
Because leading edges are difficult to repair, worn swing arms may be frequently replaced with new swing arms.
Some embodiments disclosed herein include the realization that swing arm assemblies of a debarker apparatus can have one or more replaceable inserts. The inserts can be positioned to engage the logs and, thus, may be subjected to cyclic loading. In some embodiments, the inserts are comprised mostly of a high wear resistant material, such as hardened materials, for a prolonged life. If the inserts are not performing properly, the inserts can be quickly replaced. After the inserts have been worn a predetermined amount, for example, the inserts can be quickly replaced resulting in less machine downtime as compared to the downtime required to replace swing arm assemblies or form new leading edges. The inserts can provide suitable high wear surfaces, edges, or other contact regions for engaging logs.
The insert and a main body of the swing arm assembly can each have one or more fastener areas. Complementary fastener areas can facilitate proper positioning of the insert. In some embodiments, the insert comprises a fastener area having a plurality of discrete fastening features positioned to mate with a plurality of discrete fastening features of a fastener area of the main body. The fastening features can be holes, fasteners, or other suitable fastening features.
A working end of the swing arm is configured to remove bark from the log as the carriage rotates. A main body of the swing arm extends between the mounting end and working end. An insert is removably coupled to the main body and is configured to cause the swing arm assembly to move from the inner position towards the outer position when the insert engages an end face of the log moving along the processing line towards the insert while the carriage rotates
In some embodiments, an apparatus for removing bark from a log is provided. The apparatus includes a rotatable carriage having an opening sized to receive a log moving along a processing line passing through the opening. The swing arm assembly also includes a mounting end rotatably coupled to the carriage such that the swing arm assembly is movable between an inner position and an outer position. A working end of the swing arm is configured to remove bark from the log as the carriage rotates. A main body of the swing arm extends between the mounting end and working end. An insert is removably coupled to the main body and is configured to cause the swing arm assembly to move from the inner position towards the outer position when the insert engages an end face of the log moving along the processing line towards the insert while the carriage rotates.
In some embodiments, the insert extends away from a sidewall of receiving portion (e.g., a recess) outwardly past the main body to form a leading edge for contacting logs.
In some embodiments, the working end has a removable debarking tool. In some embodiments, the main body includes an insert receiving recess positioned between the debarking tool and the mounting end. The insert can be positioned in the recess. The insert abuts a sidewall of the recess and protrudes outwardly from the recess and main body to define a leading edge spaced from the main body. The leading edge causes the swing arm to move from the inner position when the leading edge engages the log.
In some embodiments, the main body is physically connected to the mounting end and the working end. The main body can be a unitary body that extends continuously between the mounting end and the working end. The insert can also be removed without damaging the main body.
In yet other embodiments, a swing arm assembly for removing material from a log comprises a mounting end, debarker tool, main body, and an insert. The mounting end is configured to rotatably couple the swing arm assembly to a debarker. The debarker tool end is configured for receiving a tool adapted for removing bark from the log. The main body extends between the mounting end and debarker tool end. The main body also has a receiving portion. The insert is adapted to be removably coupled to the receiving portion. The insert extends longitudinally along at least a portion of the main body from a location proximate the debarker tool.
In some other embodiments, an insert for coupling to a swing arm assembly with a receiving section is provided. The insert includes a main body, an edge portion, and at least one fastener area. The main body is dimensioned to be closely received in the receiving section of the swing arm assembly. The edge portion is connected to the main body. The edge portion extends along a generally curved path and is configured to physically engage a log to facilitate movement of the swing arm assembly from a first, closed position to a second, open position when the insert is installed on the swing arm assembly and the edge portion contacts an end face of the log during operation. The fastener area is positioned along the main body and is configured to mate with a fastener for removably coupling the insert to the swing arm assembly.
In some embodiments, a method of installing an insert on a debarker swing arm assembly having a receiving portion is provided. The method includes positioning a replaceable insert in the receiving portion of the debarker swing arm assembly. The receiving portion is positioned between a debarker tool and a mounting end of the debarker swing arm assembly. The debarker tool is configured to remove bark. The mounting end is rotatably coupleable to the debarker apparatus. The insert is removably coupleable to the receiving portion with one or more fasteners.
In some embodiments, an apparatus for removing bark from a log includes a rotatable carriage for receiving a log. A swing arm assembly of the apparatus includes a mounting end rotatably coupled to the carriage such that the swing arm assembly is movable between an inner position and an outer position. A camming member is coupled to the swing arm assembly. In some embodiments, the camming member can be an insert configured to slide along a log. In some embodiments, the camming member is an elongate protective member for mounting directly to a main body of the swing arm assembly.
The present detailed description is generally directed towards a debarker apparatus with a plurality of swing arm assemblies, each having at least one replaceable insert. Some embodiments of the swing arm assemblies have a replaceable insert that defines a contact surface, such as a leading edge, for engaging logs. Many specific details of certain exemplary embodiments are set forth in the following description and in
Additionally, the swing arm assemblies are disclosed in the context of log debarkers because they have particular utility in this context. However, the swing arm assemblies can be used in other contexts. For example, the swing arm assemblies can be used to slice bark or otherwise process logs, lumber, and the like. Terms, such as “inward,” “outward,” “proximal,” and “distal,” are used to describe the illustrated embodiments and are used consistently with the description of non-limiting exemplary applications. The terms “proximal” and “distal” are used in reference to a log when the debarker apparatus processes the log, unless the context clearly indicates otherwise. For example, a proximal feature of the swing arm assembly is closer to the log than a distal feature of the swing arm assembly. It will be appreciated, however, that the illustrated embodiments can be located or oriented in a variety of desired positions.
It should be noted that, as used in this specification and the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the content clearly dictates otherwise. It should also be noted that the term “or” is generally employed in its sense including “and/or” unless the content clearly dictates otherwise. For purposes of this description and for clarity, a debarker apparatus will be described and then a description of its components will follow.
Logs are transported lengthwise along the processing line 131 while the carriage 106 rotates. The illustrated carriage 106 is rotated in the clockwise direction (indicated by the arrow 134 in
Because logs repeatedly strike the inserts 121a-f, the inserts 121a-f may be formed in whole or in part of a wear resistant material to minimize wear. Even so, the inserts 121a-f may become dull, deformed, worn, roughened, and/or otherwise damaged, especially after extended use. To enhance performance of the swing arm assemblies 110a-f, damaged inserts 121a-f can advantageously be replaced with new inserts thereby ensuring proper operation of the swing arm assemblies 110a-f. If the leading edges of the inserts 121a-f scrape enough wood from the ends of the logs, for example, the swing arm assemblies 110a-f may not self-open properly. The inserts 121a-f can be replaced as needed to provide proper self-opening of the swing arm assemblies 110a-f and also limit or minimize damage to the ends of the logs, thus increasing the amount of usable wood resulting in increased lumber production.
As noted above, the swing arm assemblies 110a-f rotate outwardly in a self-opening manner until the working ends of the swing arm assemblies 110a-f engage the periphery of the log. The carriage 106 then rotates the swing arm assemblies 110a-f about the log 130 such that the working ends of the swing arm assemblies 110a-f move along a helical path to process (e.g., scrape, cut, or roughen) the outer surface on the logs. The illustrated swing arm assemblies 110a-f are configured to scrape a desired amount of bark from the logs.
Various types of carriages can be used with the swing arm assemblies 110a-f. The illustrated carriage 106 is rotatably coupled to a debarker drive system 141 and biases the swing arm assemblies 110a-f inwardly against the log 130 with a desired force (e.g., a constant or variable force). One or more biasing systems in the carriage 106 are utilized to bias the swing arm assemblies 110a-f. Thus, the debarker apparatus 100 can controllably increase or decrease the amount of material removed from the logs.
The working end 144 is configured to scrape bark from a log. As used herein, the term “working end” is a broad term and generally refers, without limitation, to a distal end of a swing arm assembly having one or more debarker tools or other elements for bark removal. The working end can have a one-piece or multi-piece construction. For example, the illustrated working end 144 has a removable debarking tool 151, including a scraping knife 152 connected to a body 154. In other embodiments, the working end 144 is integral with the swing arm assembly 110a. For example, the working end 144 can be a sharpened knife monolithically formed with the main body 150. The design of the working end 144 can be selected based on line speeds, sizes and types of logs to be processed, and other operating parameters known in the art.
The insert 121a is detachably mounted to an insert receiving portion 170 of the main body 150. A plurality of fasteners 172a-c fixedly couples the insert 121a to the insert receiving portion 170. The term “fastener” is a broad term and generally refers, without limitation, to one or more devices or structures that are capable of coupling an insert to the main body of a swing arm assembly during normal use. A fastener can include, but is not limited to, one or more nut/bolt assemblies, pin/rod assemblies, threaded members, nuts, combinations thereof, and the like. As used herein, the term “bolt” is to be construed broadly and may include, without limitation, an externally threaded fastener that can be inserted through a hole (e.g., circular holes, elliptical holes, and the like) and configured to receive a threaded nut. A bolt, in some embodiments, may have a head (e.g., a hexagonal head, square head, slotted head, etc.) that engages the surface of the insert 121a or main body 150 of the swing arm assembly 110a. The term “nut” is a broad term and generally refers, without limitation, to internally threaded members that can be threadably coupled to a bolt. For example, the openings in the swing arm assembly 110a and/or the insert 121 can be threaded to engage the bolt.
The illustrated fasteners 172a-c comprise bolts 174a-c, respectively, extending through both the insert 121a and a base member 180 of the main body 150. Nuts 176a-c are threadably coupled to the bolts 174a-c, respectively. The fasteners 172a-c pull the insert 121a securely against the main body 150. Of course, the fasteners 172a-c can be used to tighten or loosen the insert 121a.
The fasteners 172a-c can also be operated for conveniently and quickly decoupling the insert 121a from the main body 150. Unlike welds or other types of built-up leading edges, the inserts can be rapidly replaced without damaging the underlying main body 150. This reduces the offline time and therefore increases production.
With continued reference to
Other types of mounting arrangements can also be used to couple the swing arm assemblies 110a-f to the carriage 106. For example, each of the swing arm assemblies 110a-f can have a mounting end with an outwardly extending drive shaft. Each drive shaft can be received within a complementary chuck of the carriage 106. To articulate the swing arm assemblies 110a-f, the chucks can apply moments to the swing arm assemblies 110a-f as desired.
As shown in
With reference again to
The sidewall 224 can act as a stop to inhibit, limit, or substantially prevent relative movement between the insert 121a and main body 150. When the log strikes the insert 121a, for example, the sidewall 224 can provide a reactive force that inhibits, limits, or substantially prevents movement of the insert 121a. Thus, the receiving portion 170 maintains the proper positioning of the insert 121a, even after continued use over a long period of time. The sidewall 224 can be generally perpendicular to the direction of the axially loads applied by the logs to reduce sliding between the insert 121a and sidewall 224. However, the sidewall 224 can also be at other orientations.
Additionally, the sidewall 224 can limit loads applied to the fasteners 172a-c. For example, the sidewall 224 can provide sufficient reactive forces to limit shear loads applied to the fasteners 172a-c below desired levels. The receiving portion 170 therefore inhibits, limits, or substantially prevents damage (e.g., deformation, shearing, etc.) to the fasteners 172a-c.
The depth D of the receiving portion 170 can be selected such a portion of the insert 121a is nested in the receiving portion 170. In the illustrated embodiment of
The illustrated insert receiving portion 170 is a strip-like recess as viewed from below (see
The configuration of the receiving portion 170 can be selected based on the configuration of the insert to be positioned therein. That is, the shape and dimensions (e.g., the length, width, etc.) of the receiving portion 170 can generally match the shape and dimensions of the insert 121a. The exposed surfaces of the insert 121a are positioned to engage logs. Because the insert 121a and receiving portion 170 have complementary configurations, the insert 121a can be nested in the receiving portion 170 such that the insert 121a is fixedly coupled to the main body 150, even when logs strike the insert 121a with significant forces.
In other embodiments, the insert 121a may not be positioned within an insert receiving portion. If the insert 121a is used as a retrofit, for example, the insert 121a can be mounted to a swing arm without an insert receiving portion. In such embodiments, stops or other types of positioners can be added to the swing arm to limit movement of the insert.
With continued reference to
The fastener areas 256, 219 can have any suitable number of throughholes. The illustrated fastener area 256 includes three countersunk throughholes 257a-c for receiving tapered bolt heads. However, the throughholes 257a-c can have other configurations.
With continued reference to
The insert 121a can subtend various angles. The illustrated insert 121a of
To install the insert 121a, the fastener area 256 of the insert 121a is aligned with the fastener area 219 of the main body 150 of the swing arm assembly 110a. In the illustrated embodiment, the throughholes 257a-c of the fastener area 256 are registered with corresponding throughholes 221a-c of the fastener area 219. The fasteners 172a-c are then assembled.
When assembled, the leading edge portion 250 can protrude outwardly from the main body 150, as shown in
The illustrated insert 121a has a unitary, one-piece construction. In other embodiments, the insert 121a can have a multi-piece construction. For example, a plurality of inserts can form the insert 121a. Advantageously, a damaged insert can be replaced without replacing all of the inserts.
The insert 121a can comprise a hardened material to prevent excessive wear to contact areas and increase its useful life. As used herein, the term “hardened material” is a broad term and includes, but is not limited to, materials that have a high wear resistance, such as tungsten/cobalt carbide, hardened steel alloys, carbide alloys, combinations thereof, or other high wear materials.
In some embodiments, the insert 121a and main body 150 are formed of similar materials, or the same material. In other embodiments, the insert 121a and main body 150 are formed of different materials. For example, the insert 121a can comprise mostly a first material. The main body 150 can comprise mostly a second material which is different than the first material. In some embodiments, the main body 150 can be formed of steel or other suitable material for withstanding large loads. The insert 121a can be formed of a harder material which may be especially well suited for sliding along logs with a minimal amount of wear. In one exemplary non-limiting embodiment, the main body 150 can be cast or formed of steel, and the insert 121a can be cast or formed of a harder material, such as a hardened steel alloy, tool steel, carbide alloy, and the like. Thus, materials can be selected and positioned along the swing arm assembly based on physical properties, material costs, weight, corrosion resistance, and the like.
To install the insert 121a, the insert 121a can be positioned in the receiving portion 170 of the debarker swing arm, as noted above. The fastener area 256 of the insert 121a can be mated with the complementary fastener area 219 of the receiving portion 170. The insert 121a can be at least proximate the sidewall 224. The mounting surface 261 of the insert 121a can rest against the receiving surface 225 of the receiving portion 170. The fasteners 172a-c can be used to removably couple the insert 121a to the receiving portion 170. The fasteners 172a-c can extend through the mounting surface 261 and receiving surface 225 and can be operated to adjust the contact forces between the mounting surface 261 and the receiving surface 225. The openings can be countersunk. The assembled swing arm assembly 110a can then be used to debark logs.
After the insert 121a has been worn a predetermined amount, the insert 121a can be replaced. The fasteners 172a-c can be disengaged from the swing arm assembly 110a to permit removal of the insert 121a. After removing the insert 121a from the receiving portion 170, a second insert can be placed in the receiving portion 170. The second insert may be similar to or different than the first insert 121a. The fasteners 172a-c can couple the new insert to the receiving portion 170 in a similar manner. This replacement process can be repeated any number of times as desired or needed.
The swing arm assemblies 110a-f of
The fastener area of the inserts can include one or more nipples, threaded members, or other types of fasteners that can be received by complementary features on the main body. The type and configuration of the fastener area can be selected based on operating parameters, such as line speeds, thickness of bark to be removed, and the like.
Various methods and techniques described above provide a number of ways to carryout the invention. Of course, it is to be understood that not necessarily all objectives or advantages described may be achieved in accordance with any particular embodiment described herein. Thus, for example, those skilled in the art will recognize that the methods may be performed in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other objectives or advantages as may be taught or suggested herein.
Furthermore, the skilled artisan will recognize the interchangeability of various features from different embodiments disclosed herein. Similarly, the various features and acts discussed above, as well as other known equivalents for each such feature or act, can be mixed and matched by one of ordinary skill in this art to perform methods in accordance with principles described herein. Additionally, the methods which are described and illustrated herein are not limited to the exact sequence of acts described, nor are they necessarily limited to the practice of all of the acts set forth. Other sequences of events or acts, or less than all of the events, or simultaneous occurrence of the events, may be utilized in practicing the embodiments of the invention.
Although the invention has been disclosed in the context of certain embodiments and examples, it will be understood by those skilled in the art that the invention extends beyond the specifically disclosed embodiments to other alternative embodiments and/or uses and obvious modifications and equivalents thereof. Accordingly, it is not intended that the invention be limited, except as by the appended claims.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/US2007/081564 | 10/16/2007 | WO | 00 | 3/4/2010 |
Publishing Document | Publishing Date | Country | Kind |
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WO2008/105963 | 9/4/2008 | WO | A |
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Number | Date | Country | |
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20100154932 A1 | Jun 2010 | US |
Number | Date | Country | |
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Parent | 11582125 | Oct 2006 | US |
Child | 12445280 | US |