Patent Application
20170080594
Not applicable.
Not applicable.
This disclosure relates to cutting devices, such as large saw discs for work vehicles or harvesting implements used in the forestry industry.
Various work vehicles and harvesting implements may include a rotary cutting device. In the forestry industry, for example, a wheeled or tracked feller buncher may have a felling head with a circular saw that is used to cut down standing trees. Saw discs of this type having a large diameter (e.g., up to 58 inches/1,473 mm or more) circular plate (e.g., over 1 inch/25 mm thick) with a number of large cutting teeth (e.g., 16-20) arranged on mounting lugs spaced around the circumference of the disc. The large size and operational speed (e.g., 1,275 rpm) of such saw discs generate high inertial forces that may allow the saw discs to rapidly cut through the full trunk of the tree in a single pass. This cutting processing thus imparts high forces on the disc teeth that cause significant wear over time. Thus, it is beneficial to have a tooth assembly and mounting arrangement which are secure, and yet allow for the teeth to be replaced, or otherwise adjusted for positioning a sharpened cutting edge in the cutting plane of the saw disc path.
This disclosure provides a cutting tooth configuration and a mounting arrangement for the cutting teeth on a cutting device that is secure, while at the same time readily adjustable for repositioning and/or replacing a sharpened cutting edge of the teeth in the cutting path.
In one aspect the disclosure provides a tooth for a cutting device that may have a tooth mounting lug defining a V-shaped lug mounting profile extending between first and second sides of the tooth mount in a radial or axial direction of the mounting lug. The tooth may have a shank-less body defining a cutting profile at a cutting face of the body and a tooth mounting profile at a mounting face of the body having a configuration for complementary engagement with the lug mounting profile. The tooth body may have a through hole extending from the cutting face through the mounting face for receiving a fastener to mount the tooth to the lug. The tooth mounting profile may have first and second flat surfaces engageable with the lug mounting profile so that the flat surfaces positively resist rotation of the tooth with respect to the lug about the fastener when the tooth is mounted to the lug. In this position, a radially inner side of the tooth extending between the cutting and mounting faces is spaced from the lug and the cutting device.
In another aspect the disclosure provides a tooth assembly for a cutting device, including a tooth and a tooth mount. The tooth mount may be fixed with respect to the cutting device and define a first mounting profile with first and second flat mount surfaces extending between first and second sides of the tooth mount in a radial or axial direction of the tooth mount. The tooth is mountable to the tooth mount and may define a second mounting profile, opposite a cutting profile of the tooth. The second mounting profiled has first and second flat tooth surfaces extending between first and second sides of the tooth in the direction of the cutting device along which the first and second flat mount surfaces extend. One of the first and second mounting profiles may define a V-shaped mounting groove and the other of the first and second mounting profiles may define a mounting projection configured to inter-fit with the mounting groove such that the first and second flat mount surfaces engage the respective first and second flat tooth surfaces. A radially inner side of the tooth may be spaced from the tooth mount and the cutting device.
In still another aspect the disclosure provides a cutting device including a circular plate that may be disposed concentrically about a rotation axis and centered on a reference plane which is perpendicular to the rotation axis. The circular plate may have an outer peripheral edge defining a plurality of mounting lugs extending radially out from the outer peripheral edge and spaced apart angularly along the outer peripheral edge. The mounting lugs may form tooth mounts, each defining a first mounting profile forming a V-shaped groove with first and second flat mount surfaces centered about the reference plane and extending between first and second sides of the mounting lug in a radial or axial direction of the saw disc parallel to the rotation axis of the saw disc. A plurality of teeth may be mountable to the mounting lugs, each tooth defining a second mounting profile opposite a cutting profile of the tooth. The second mounting profile may have first and second flat tooth surfaces extending between first and second sides of the tooth in the radial or axial direction. When mounted to the tooth mount, a radially inner side of the tooth is spaced from the outer peripheral edge of the circular plate. A plurality of fasteners may couple the teeth to the mounting lugs. Each of the fasteners extends along an axis contained in the reference plane and clamping the flat tooth surfaces against the flat mount surfaces.
The details of one or more embodiments are set forth in the accompanying drawings and the description below. Other features and advantages will become apparent from the description, the drawings, and the claims.
Like reference symbols in the various drawings indicate like elements.
The following detailed description includes one or more example embodiments of the disclosed cutting tooth configuration and mounting arrangement for a saw disc, as shown in the accompanying figures of the drawings described briefly above. Various modifications to the example embodiments may be contemplated by one of skill in the art.
The present disclosure provides an improved cutting tooth and arrangement for mounting cutting teeth on mounting lugs of a saw disc. The disclosed tooth configuration and mounting arrangement is particularly useful for large saw discs used in industrial applications, such as for felling trees in the forestry industry. However, the cutting tooth configuration and mounting arrangement may be useful for saw discs used in other applications and industries.
In one perspective, aspects of the disclosed tooth configuration and mounting arrangement better ensure a robust, secure connection of the cutting teeth to the mounting lugs, which is useful for maintaining secure engagement and proper alignment of the cutting teeth with the saw disc during cutting operations. Reducing misalignment of the cutting teeth, which can slow the cutting operation and dull the cutting edges of the teeth, may be particularly useful for cutting operations, such as tree felling, in which the saw disc is large, such that the saw disc, and thereby the cutting teeth, engage the cut at high angular velocities and corresponding high impact forces on the cutting teeth. In certain embodiments, the mounting interface between the teeth and the lugs may have flat engaging surfaces that positively retain the tooth in a cutting alignment.
From another perspective, the disclosed tooth configuration and mounting arrangement may be considered as facilitating the replacement of the cutting edges. In certain embodiments, the disclosed cutting tooth configuration may have a double-edged, or otherwise multi-sided, cutting profile in which one, or some number fewer cutting edges of the cutting profile are arranged in the cutting path of a particular cutting operation. The mounting arrangement disclosed allows for one cutting edge to be replaced by another cutting edge at the cutting path with completely disassembling the tooth from the saw disc, thus reducing the time and complexity required to change cutting edges.
For example, in certain embodiments, the configuration of the disclosed cutting teeth and mounting lugs allows for one tooth rotation of 180 (or other) degrees to reposition a new cutting edge in the cutting path of the saw disc. The tooth may be indexed by loosening and removing a single retention bolt and rotating the tooth 180 degrees. In certain embodiments, such as a one having a sufficiently shallow tooth mounting interface and a bolt of sufficient length, the tooth may be indexed by loosening and rotating the tooth without removing the fastener and dismounting the tooth. Such indexing may be aided in part by the radially inner side of the tooth being spaced from the outer peripheral edge of the lug and/or the saw disc so that the tooth may be rotated without being dismounted entirely and without an edge or side surface of the tooth contacting the mounting lug or the saw disc. The periphery of the saw disc may have a relief formed adjacent the mounting lug to provide this spacing of the radial inner side of the tooth without requiring the radial inner side of the tooth to be spaced radially outward of the nominal outer diameter of the saw disc.
In yet another perspective, the disclosed tooth configuration and mounting arrangement may be considered to simplify the manufacturing required to produce a saw disc of the type disclosed. For example, in certain embodiments, mounting lugs may be cut into, or formed as part of, the periphery of a tooth or saw disc. For example, in some embodiments the saw disc may be a steel plate, and each tooth may be a casting or forging, although other conventional processes may be used for both the saw disc and the teeth. Aspects of the disclosed cutting tooth and lug configuration may allow the entire periphery to be machined with a reduced need to change tool sizes. A multi-pass machining operation, including for example a rough cut pass and a finishing cut pass, may be used to machine each tooth and the periphery of the saw disc. By avoiding small radii areas, a single cutting tool may be used for each of the rough and finishing passes to machine each tooth and the entire periphery of the saw disc. For example, the mounting profiles of the teeth and the lugs may extend full-width across these components so as to avoid creating interior surfaces or tight-radius corners that require machining. Further, the aforementioned relief in the periphery of the saw disc also avoids the need for square corners in a radial direction or radii smaller than the cutting tool, such that the teeth are mounted at the lugs without interference with the remainder of the saw disc, which greatly reduces the level of precision required in machining at the interface of the teeth and saw disc.
Assembly is also made easier by certain aspects of the tooth configuration and the mounting arrangement disclosed. For example, the cutting tooth may be shank-less and a separate threaded fastener (e.g., a bolt) may be used to secure a tooth to its mounting lug. Moreover, the bolt or other threaded fastener may be mounted from the exposed cutting face side of the cutting tooth rather than from a concealed or low-access area of the device. In the case of a bolt, its enlarged head may be received in a multi-sided recess or pocket such that not only is it located not to interfere with the cutting plane, the tooth may be installed and adjusted with a single tool (e.g., a screw or socket driver) without the need to hold the bolt with a second tool. Furthermore, neither the tooth nor the mounting lug would need to be tapped with a threaded opening, or only one of the tooth and the lug would need to be tapped if no nut was used. The tooth and the lug each could simply have a through bore (e.g., from a drilling operation), without the need to thread the tooth bore or the lug bore for the bolt opening. Further, an unthreaded portion shank of the bolt is in shear at the tooth-mounting lug interface, thus maximizing the shear area for a given bolt diameter, and with the bolt head located in the recess, it will not interfere with cutting or material flow.
In certain embodiments, the tooth and the lug may have complementary interlocking groove and projection mounting profiles. For example, the tooth may have a generally V-shaped mounting face that matches with a generally V-shaped mounting profile formed in the lug. In this regard, the “V-shaped” as used herein in refers to a profile configuration having a cross-section with two converging flat sides. It should be understood that the converging flat sides need not be symmetrical with, or at the same angle to, a central plane, nor do the flat sides need to intersect along a common centerline. Rather, the area between the converging flat surfaces (i.e., the projecting bottom of the “V” in the male component or the bottom of the valley or groove of the female component) may define a sharp edge line and angle included, or it may be rounded or flat. The use of mating flat surfaces provides a positive, anti-rotation feature of the mounting arrangement to maintain proper tooth alignment during cutting operations. However, the converging angulation of these flat surfaces, may in some cases, allow the tooth to be indexed (e.g., rotated 180 degrees) when the tooth is loosened, but still retained to the lug, to swap cutting edges. Further, it should be understood that the tooth may form the projection, or male V-shaped component, and the lug may form the groove or valley, or female V-shaped component, or vice versa.
The valley of the V-shaped mounting profiles may run in either a radial or an axial direction with respect to the saw disc. In this regard, as used herein, the term “axial” refers to a direction that is generally parallel to an axis of rotation, axis of symmetry, or centerline of a component or components. For example, in a cylinder or disc with a centerline and opposite, generally circular ends or faces, the “axial” direction may refer to the direction that generally extends in parallel to the centerline between the opposite ends or faces. In certain instances, the term “axial” may be utilized with respect to components that are not cylindrical (or otherwise radially symmetric). For example, the “axial” direction for a rectangular housing containing a rotating shaft may be viewed as a direction that is generally in parallel with the rotational axis of the shaft. Furthermore, the term “radially” as used herein may refer to a direction or a relationship of components with respect to a line extending outward from a shared centerline, axis, or similar reference, for example in a plane of a cylinder or disc that is perpendicular to the centerline or axis. In certain instances, components may be viewed as “radially” aligned even though one or both of the components may not be cylindrical (or otherwise radially symmetric). Furthermore, the terms “axial” and “radial” (and any derivatives) may encompass directional relationships that are other than precisely aligned with (e.g., oblique to) the true axial and radial dimensions, provided the relationship is predominately in the respective nominal axial or radial direction.
The mounting profiles of the tooth and/or the lug may have other shapes or features without departing from the scope and spirit of the disclosed subject matter. For example, either the tooth or the lug, or both, may have other interlocking features, such as squared tongue and groove features. Flanks may extend from the tooth along sides of the lug for added structural support, thereby requiring less bolt strength for retention and anti-rotation. Thus, one skilled in the art will recognize that this mounting configuration provides flexibility in the placement and form of the cutting teeth, which may be full width, with both top and bottom of tooth contacting the cut, or recessed on one side and staggered such that only one side of the tooth only forms the cutting edge, or skewed so as to create a single cutting point.
The cutting edges of the tooth may be formed integrally with the cutting face or profile and coated with hard, cutting material. Alternatively, one or more separate cutting tips, such as straight pieces of carbide, may be attached across the width of the tooth at one, two or more upper edges to define the cutting face or profile of the tooth.
Thus, the tooth configuration and mounting arrangement disclosed herein yield positive and robust tooth positioning, while allowing several improvements over conventional saw discs. This has the benefit of being less sensitive to bending stresses, and thus less prone to cracking. In addition, less complex machining is needed for the fabrication of the teeth and saw disc. The design of the teeth and the mounting lugs eliminates small radii which simplifies machining operation and reduces associated stress concentrations, and thus the chance of cracking. The through holes in the teeth and the mounting lugs are clearance holes for the through bolts, which clamp the teeth to the mounting lugs, and therefore require less working since they do not need to be threaded or bored to a controlled dimension.
With reference now to the drawings, example saw disc assemblies, and the mounting arrangements for cutting teeth on the saw disc, will be described in the context of a work vehicle in the form of a track feller buncher having a saw disc felling head. While a tracked feller buncher is discussed herein as an example work vehicle, one skilled in the art will recognize that the configuration of the teeth and mounting arrangement disclosed herein may be readily adapted for use on other saw blade assemblies and/or cutting heads. As such, the present disclosure should not be limited to applications associated with a feller buncher or the disc saw felling head saw assembly.
As shown in
With reference now to
Referring now to
As illustrated in
As noted above, the cutting tooth 52 is mounted and secured to the mounting lug 50. Specifically, the first and second planar surface 66, 68 on the cutting tooth 52 are positioned in complementary engagement with the first and second planar surface 84, 86 of the mounting lug 50. The fastener 56 extends through the through bores 72 and 90 with the hexagonal head 74 recessed in the tooth body 54 and a threaded portion 92 extending past the trailing face 80 of the mounting lug 50. A nut 94 is threadably secured to the threaded portion 92 of the fastener 56 to engage the trailing face 80. Once tightened, the fastener 56 clamps the planar surfaces 66, 68 of the cutting tooth 52 onto the planar surfaces 84, 86 of the mounting lug 50. This clamping force, in combination with the configuration of the complimentary, V-shaped mounting profiles of the mounting face 62 and the tooth mount 82, maintain the proper alignment of the cutting edge of the cutting tooth 52 during cutting operations with the saw disc assembly 42. In other words, the first and second planar surfaces 66, 68 positively position the cutting tooth 52 and prevent rotation thereof with respect to the mounting lug 50 about the fastener 56.
As shown in
The cutting profile of each tooth may be of any suitable configuration and construction. In the illustrated example of
The cutting profiles 58A, 58B may be indexed in a simple and rapid manner by loosening the fastener 56 sufficiently, which may by complete removal or loosening short of removal of the fastener, so that cutting tooth 52 may be rotated relative to the mounting lug 50 through 180 degrees so the second cutting profile 58B is located in the use position. Once rotated, the fastener 56 may be re-tightened such the planar surfaces 66, 68 of the cutting tooth 52 are respectively clamped onto the planar surfaces 84, 86 of the mounting lug 50. Additionally, side surfaces, primarily inner radial side 67, of the cutting tooth 52 are spaced from the mounting lug 50 and the outer peripheral edge 46 of the plate 44. In the illustrated example, this gap clearance is provided by the relief 96 in the outer peripheral edge 46 of the plate 44. In this configuration, spacing of the cutting tooth 52 in the radial dimension can be reduced, such that the radial inner side 67 of the cutting tooth 52 may lie radially inward (toward the axis of rotation R) of the nominal outer diameter of the plate 44, along which lie arcuate portions of the outer peripheral edge 46 between the relief 96 and a consecutive mounting lug 50.
The tooth assembly 48 and more specifically the mounting profiles on the mounting face 62 and the tooth mount 82 have been described in terms of an example V-shaped profile which is aligned in the axial direction of the saw disc. One skilled in the art should, however, appreciate that these mounting profiles may be modified and/or varied without departing from the scope and spirit of this disclosure. In this regard, it will be recognized that the mounting profile includes a feature or features that provide for a positive positioning of the cutting tooth relative to the mounting lug and sufficient surface area to generate adequate clamping forces therebetween. With reference now to
As used herein, unless otherwise limited or modified, lists with elements that are separated by conjunctive terms (e.g., “and”) and that are also preceded by the phrase “one or more of” or “at least one of” indicate configurations or arrangements that potentially include individual elements of the list, or any combination thereof. For example, “at least one of A, B, and C” or “one or more of A, B, and C” indicates the possibilities of only A, only B, only C, or any combination of two or more of A, B, and C (e.g., A and B; B and C; A and C; or A, B, and C).
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that any use of the terms “comprises” and/or “comprising” in this specification specifies the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
The description of the present disclosure has been presented for purposes of illustration and description, but is not intended to be exhaustive or limited to the disclosure in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the disclosure. Explicitly referenced embodiments herein were chosen and described in order to best explain the principles of the disclosure and their practical application, and to enable others of ordinary skill in the art to understand the disclosure and recognize many alternatives, modifications, and variations on the described example(s). Accordingly, various implementations other than those explicitly described are within the scope of the claims.
