This application is being filed on 13 October 2015, as a PCT

International patent application, and claims priority to U.S. Provisional Patent Application No. 62/065,400, filed October 17, 2014, the disclosure of which is hereby incorporated by reference herein in its entirety.

TECHNICAL FIELD

The present disclosure relates generally to a replaceable apparatus, specifically a protective wear sleeve, for mounting reducing elements used by excavation machines such as surface excavation machines.

BACKGROUND

Relatively hard materials are often processed for mining and construction. The variety of materials include rock, concrete, asphalt, coal, and a variety of other types of mineral-based materials. A number of different methods for reducing the size of these hard materials have been developed. One method has been the use of reducing machines having rotary reducing components that move rigid and specialized reducing elements through paths of travel. The reducing components can include rotating drums that move the reducing elements through circular paths of travel. Such drums are typically attached to corresponding machines with a mechanism that allows the position and orientation of the drum to be controlled, to bring the reducing elements into contact with the material being reduced. Alternative reducing components can include boom-mounted chains that carry reducing elements. The chains are typically driven/rotated about their corresponding booms. The reducing elements are mounted to and move along the paths of travel defined by the chains. In use, the booms are moved (e. g., through a pivoting motion) to positions where the reducing elements are brought into contact with the material being reduced.

The reducing elements of reducing machines have been developed to withstand the impact loads and abrasion associated with material reduction activities. Reducing elements can be constructed in a variety of shapes and sizes and have been labeled with various terms including cutters, chisels, picks, teeth, etc. Typical reducing elements include leading impact points or edges and bases. The reducing element holders, or tool holders, are constructed to fit into mounting structures that are integrated with drums or chains used to carry the reducing elements during material reducing applications. The harsh environment associated with material reducing applications virtually guarantees that the reducing elements will wear down over time.

Often, the tips or edges of the reducing elements have a harder construction (e.g., a solid carbide construction) than the tool holders of the reducing elements. When using new reducing elements to reduce material, the leading points or edges are exposed to the majority of the impacts and abrasion action. However, once the leading tips or edges become worn, the tool holders and other components are exposed to more impacts and abrasive action. A variety of potential problems can arise when this occurs, including that the tool holders are less efficient at breaking the material, causing inefficient operation. Once reducing elements are worn there is also a risk of causing damage to the mounting structures of the drums or chains.

A protective wear sleeve can be used as an intermediate wear part between the reducing element and the base. However, the most common use for these sleeves has been to reduce wear on the holder from the spinning reducing element, which tends to, over time, bore out the area that the tooth is mated next to, as described in U.S. Patent No. 8,783,785, U.S. Patent No. 8,657,385, and U.S. Patent No. 5,088,797. However, due to the harsh environment the protective wear sleeve is subjected to, the wear sleeve often also wears at a rapid rate on the exterior, thereby forcing replacement.

SUMMARY

In accordance with the following disclosure, the above and other issues are addressed by the following.

The downtime associated with replacing wear components on a cutting drum can be extensive for the machine that the drum is mounted to. Such downtime makes the machine less efficient, which leads to a higher operating cost. At the same time, if too much time is allowed to pass before replacement of wear components, other, more costly, components can be damaged, for example tool holders or the drum itself. The replacement of worn tool holders can be costly and difficult such that the tool holders are often significantly worn before they are replaced. As a result of these issues, there can be significant benefits to replacing the other wear components before wear has progressed past an unacceptable point. A protective wear sleeve provides an option as an intermediate wear part, protecting the more expensive components from rapid wear. Therefore, there is an ongoing need for a protective wear sleeve that has an extended life. An extended lifetime translates into less downtime and a lower replacement frequency. In particular, there is a need for a protective wear sleeve having wear protection on the outer exposed portion of the sleeve that is not protected by the reducing element.

According to an example aspect, the disclosure is directed to a protective wear sleeve for a tooth holder of a cutting tool assembly wherein the tooth holder contains a central bore. The protective wear sleeve includes an elongate body made from a base material, the elongate body including a tooth bore that defines a tooth axis, an axial forward end and an axial rearward end, a mount portion at the rearward end configured for an interference press-fit with the central bore of the tooth holder. The elongate body further including a tooth support collar at the forward end, the tooth support collar including a tooth support surface projecting from the tooth bore out to a tooth collar diameter. The tooth support surface facing generally in a forward direction. The tooth support collar further including a shoulder with an outer diameter equal to, or greater than, the tooth collar diameter and a shoulder thickness along the elongate axis of the body, wherein the shoulder includes a hardfacing portion.

According to another aspect, the disclosure is directed to a protective wear sleeve for a cutting tool assembly that includes a solid body having a first portion and a second portion, the body having a central bore where the central bore defines a central axis. The first portion of the solid body is a shaft portion having a forward end and a rearward end, and the second portion of the solid body is a radial collar integral with the forward end of the shaft portion. The radial collar has a ring support surface that faces at least partially in an outward radial direction. The forward end of the shaft portion and the radial collar together define a tooth support surface that faces in a forward direction, the tooth support surface having an outer diameter. At least one wear ring is disposed on the ring support surface, the at least one wear ring extending around the radial collar. The at least one wear ring has a hardness greater than that of the radial collar and has an outer diameter greater than that of the outer diameter of the tooth support surface.

According to another aspect, the disclosure is directed to an apparatus including a holding block having a protective wear sleeve opening, a cutting tooth having a support flange and a shank, and a protective wear sleeve. The protective wear sleeve includes a solid body having a first portion and a second portion, the body having a central bore for receiving the shank of the cutting tooth, the central bore defining a central axis. The first portion is a shaft portion having a forward end and a rearward end, and the second portion is a radial collar integral with the forward end of the shaft portion. The radial collar has a ring support surface that faces at least partially in an outward radial direction. The forward end of the shaft portion and the radial collar together define a tooth support surface that faces in a forward direction, the tooth support being configured to encase a back side of the support flange of the cutting tooth. The protective wear sleeve further includes at least one wear ring disposed on the ring support surface, the at least one wear ring extending around the radial collar, the at least one wear ring having a hardness greater than that of the radial collar and having an outer diameter greater than that of an outer diameter of the tooth support flange. Wherein the protective wear sleeve is press fit into the protective wear sleeve opening of the holding block, and the cutting tooth being secured in the central bore of the protective wear sleeve and being rotatable around the central axis of protective wear sleeve.

A variety of additional aspects will be set forth in the description that follows. These aspects can relate to individual features and to combinations of features. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the broad concepts upon which the embodiments disclosed herein are based. BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a front view of a portion of a surface excavation machine showing a drum with reducing elements, in accordance with the principles of the present disclosure;

FIG. 2 illustrates a perspective view of a cutting apparatus that can be mounted to the drum shown in FIG. 1 ;

FIG. 3 illustrates a front perspective view of the cutting apparatus shown in FIG. 2;

FIG. 4 illustrates a cross-sectional view of the cutting apparatus of FIG. 3 taken along line A;

FIG. 5 illustrates a perspective exploded view of the cutting apparatus shown in FIG. 2;

FIG. 6 illustrates a perspective view of a protective wear sleeve according to one embodiment of the present disclosure;

FIG. 7 illustrates a front view of the protective wear sleeve shown in

FIG. 6;

FIG. 8 illustrates a cross-sectional view of the protective wear sleeve of FIG. 7 taken along line A;

FIG. 9 illustrates a side perspective view of the protective wear

DETAILED DESCRIPTION

The present application discloses a protective wear sleeve. Because wear sleeves can be subjected to wear when a cutting action is being carried out, it is advantageous to increase the lifetime of the wear sleeve. The sleeve disclosed herein is configured to resist wear on exterior portions of the sleeve, specifically the radial collar. FIG. 1 depicts a cutting drum 38 attached to a surface excavation machine 36. The cutting drum 38 being designed to, once rotated, reduce material by way of a plurality of cutting apparatuses 40 mounted to the surface of the drum 38. The cutting apparatuses 40 can be arranged in a variety of patterns for a variety of different applications. Each cutting apparatus 40 can include a reducing element 46, or tooth, a tool holder 42 and a protective wear sleeve 10.

FIGS. 2-3 depict the cutting apparatus 40. The assembled cutting apparatus 40 can include the reducing element 46, the protective wear sleeve 10, and the tool holder 42. In some embodiments, the tool holder 42 may be secured to a base 44 for securing to a cutting drum. Further, the protective wear sleeve 10 can include a wear ring 22. The wear ring 22 can be configured to provide a high wear resistance. In some embodiments, the tool holder 42 may be one piece or include multiple pieces and other wear components.

FIG. 4 depicts a cross-sectional view along line A in FIG. 3. FIG. 5 depicts an exploded view of the cutting apparatus 40. As shown, the tool holder 42 has a wear sleeve opening 54 configured to receive the protective wear sleeve 10. The wear sleeve 10 has a central bore 12 configured to receive the tooth 46. The tooth 46 can be secured to the tool holder 42 by way of a fastener 52, such as a pin or clip. The tooth 46 can include a shank 50 and a support flange 48. The protective wear sleeve 10 can be press fit into the wear sleeve opening 54 so as to prevent rotation of the protective wear sleeve 10 relative the tool holder 42. Also, in some embodiments, the protective wear sleeve 10 can be configured so that it may be orientated in any rotational orientation within the wear sleeve opening 54, with respect to the tool holder 42. This allows for rapid installation with a lower chance of installation error. Additionally, the tooth 46 may be secured within the central bore 12 of the protective wear sleeve 10. The tooth 46 can be secured within the protective wear sleeve 10 to allow for rotation of the tooth 46. When secured in the protective wear sleeve 10, the tooth support flange 48 rests on a tooth support surface 20 of the protective wear sleeve 10. The wear ring 22 is configured to have a larger diameter than the tooth support surface 20. This is advantageous because during a mining operation, material will pass over the support flange of the tooth 46 and contact the protective wear sleeve 10. Because of this repeated contact, the material that is outside of the diameter of the tooth support flange is subjected to repeated abuse and tends to wear quickly. The wear ring 22 placed in this location is designed to slow wear to the protective wear sleeve 10 so as to extend the life of the wear sleeve, extending replacement intervals.

FIG. 6 shows a perspective view of the protective wear sleeve 10. The protective wear sleeve 10 can include a shaft portion 14 and a radial collar 16. The protective wear sleeve 10 also includes the central bore 12 that travels through the center of the protective wear sleeve 10 and defines a central axis 13. In some embodiments, the radial collar 16 can have an axial thickness C running parallel to the central axis 13 and also a radial thickness B so to have an outer diameter greater than that of the shaft portion 14. In other embodiments, the radial thickness B of the radial collar 16 can be tapered, where the portion of the radial collar 16 has a smaller thickness (i.e. smaller outer diameter) near the areas closer to the tooth support surface 20. The protective wear sleeve 10 having a forward end 17, generally being the radial collar 16, and a rearward portion 15, generally being the shaft portion 14. In the depicted embodiment, together with the shaft portion 14, the radial collar 16 can form the tooth support surface 20, the tooth support surface 20 being at the forward end 17 of the protective wear sleeve 10. The tooth support surface 20 can take on a variety of different shape but always faces in a forward direction. While the tooth support surface 20 is depicted as a planar surface, the surface can also be conical or a variety of other shapes while remaining generally forward facing. In some embodiments, the tooth support surface can be configured to be generally perpendicular to the central axis 13.

The protective wear sleeve 10 can also include the wear ring 22. The wear ring 22 can be disposed around the radial collar 16. As depicted, the wear ring 22 can be disposed 360 degrees around the radial collar 16. The wear ring 22 can be of a variety of materials. In some embodiments, the wear ring 22 can be a weld of hardfacing material. In some embodiments, the wear ring 22 can be a weld of hardfacing material that is disposed 360 degrees around the radial collar 16. In such an embodiment, the protective wear sleeve 10 can be configured to be inserted at any angular rotation about the central axis 13 and still provide hardfacing protection relative to the direction of rotational travel of the tooth 46 held by the protective wear sleeve 10. A hardfacing material can be a material that results from a process where a harder material is applied to a less hard material, the less hard material often called a base. Such a material can then be welded to the base material. In other embodiments, the wear ring 22 may comprise a material with a hardness greater than that of the radial collar 16. In other embodiments yet, the wear ring 22 may be comprised of a material with a hardness between about 40HRC and about 70HRC.

FIG. 7 depicts a front view of the protective wear sleeve of FIG. 5.

The wear ring 22 is shown to have an outer diameter greater than the outer diameter of the tooth support surface 20. This configuration allows adequate wear protection for portions of the protective wear sleeve 10 that lie outside the diameter of the tooth support surface 20, such portions being more prone to wear.

FIG. 8 shows a cross-sectional view along the section line A of FIG.

7. As shown, a portion of the shaft portion 14 is a unitary portion of radial collar 16, whereby, together, both portions behave as one piece. The tooth support surface 20 can include a portion 21 defined by the shaft portion 14 and a portion 23 defined by the radial collar 16. In the depicted embodiment the central bore 12 is shown to be stepped. In other embodiments, the central bore 12 may have a uniform diameter. Also shown in FIG. 8, the radial collar 16 can include a ring support surface 18, being configured to hold the wear ring 22. The ring support surface 18 can have a scalloped shape, or groove-like structure. In some embodiments, the ring support surface 18 can face at least partially in an outward radial direction. In other embodiments, the ring support surface 18 can face at least partially in an outward radial direction and at least partially in a forward axial direction. Alternatively, in some embodiments, the ring support surface 18 may include an about 90-degree angled shoulder. In other embodiments still, the ring support surface 18 may be machined. Additionally, the ring support surface 18 may be on the radial collar 16 near the tooth support surface 20. In other embodiments, the ring support surface 18 may be located at any location along the radial collar 16 and have a maximum axial thickness equal to the axial thickness of the radial collar 16. FIG. 9 depicts the protective wear sleeve 10 without a wear ring.

In some embodiments the interior surface of central bore 12 can be have a first hardness, the tooth support surface 20 can have a second hardness, the radial collar 16 can have a third hardness, and the wear ring 22 can have a fourth hardness. In some embodiments, the interior surface of the central bore 12 and the tooth support surface 20 may have equal hardnesses. In other embodiments, the interior surface and the central bore 12 may be induction hardened. Induction hardening takes places when a metal part is heated by induction and then quenched. The process changes the material properties of the metal part, thereby increasing its hardness and brittleness. In still other embodiments, the wear ring 22 can have a hardness greater than that of the radial collar 16, and less than that of the tooth support surface 20 and interior surface of the central bore 12. In still other embodiments, the wear ring 22 can have a hardness greater than that of the radial collar 16, the tooth support surface 20 and interior surface of the central bore 12. In the same embodiment, the radial collar 16 may have a hardness less than that of the tooth support surface 20 and the interior surface of the central bore 12. In some embodiments, the radial collar 16 can have a hardness between about 20HRC and about 30HRC. In other embodiments, the tooth support surface 20 and the inner surface of the central bore 12 can have a hardness between about 50HRC and about 60HRC. In other embodiments still, the radial collar 16 and the shaft portion 14 can be of 4140 steel.

In some embodiments the shaft 14 can have a length between about 3 inches and about 4 inches. In some embodiments, the central bore 12 may have an outer diameter between about 1.70 inches and about 1.75 inches. In other embodiments, the tooth support surface 120 can have an outer diameter between about 3 inches and about 4.75 inches. In other embodiments still, the wear ring 22 can have an outer diameter between about 3 inches and about 4.75 inches. In other embodiments, the shaft portion 14 can have an outer diameter between about 2.250 inches and about 2.260 inches.

FIG. 10 depicts a protective wear sleeve 110 according to one embodiment of the present disclosure. The protective wear sleeve 110 of FIG. 10 is similar to that of the protective wear sleeve 10 of FIG. 7. Similarly, the protective wear sleeve 110 includes a shaft portion 114, a radial collar portion 116, a central bore 112, a central axis 113, a forward portion 117, a rearward portion 115, a ring support surface 118, a tooth support surface 120, and a wear ring 122a, 122b. In FIG. 10 the protective wear sleeve 110 includes a wear ring that includes two individual wear rings 122a and 122b. In other embodiments, a plurality of wear rings may be disposed around the radial collar 1 16 of varying thicknesses and diameters. In the depicted embodiment, the first wear ring 122a has a smaller outer diameter than the second wear ring 122b and is positioned closer to the tooth support surface 120, or forward end of the protective wear sleeve 110. In other embodiments, the plurality of wear rings can have the same outer diameter. The wear rings 122a, 122b can be of a variety of materials. In some embodiments, the wear rings 122a, 122b can be welds of hardfacing material. In other embodiments, the wear rings 122a, 122b may comprise a material with a hardness greater than that of the radial collar 1 16. In other embodiments yet, the wear rings 122a, 122b may be comprised of a material with a hardness between about 40HRC and about 70HRC. In still other embodiments, the wear rings 122a, 122b may have differing hardnesses, each between about 40HRC and about 70HRC.

FIG. 11 depicts a front view of the protective wear sleeve of FIG. 10. The wear rings 122a, 122b are shown to have outer diameters greater than the outer diameter of the tooth support surface 120. Additionally, as shown, the wear ring 122a has a larger outer diameter than the wear ring 122b. This orientation allows for adequate wear protection for portions of the protective wear sleeve 110 that lie outside the diameter of the tooth support surface 120, such portions being more prone to wear.

FIG. 12 shows a cross-sectional view of the protective wear sleeve 1 10 along the section line A of FIG. 11. Similar to the protective wear sleeve 10 above, a portion of the shaft portion 114 is a unitary portion of radial collar 116, whereby, together, both portions behave as one piece. The tooth support surface 120 can include a portion 121 defined by the shaft portion 114 and a portion 123 defined by the radial collar 1 16. Also, the radial collar 116 can have a radial thickness D and an axial thickness E. As shown in FIG. 11, the radial collar 116 can include a plurality of ring support surfaces 118a, 118b, the support surfaces 118a, 1 18b being configured to hold a plurality of wear rings. While the depicted embodiment shows two ring support surfaces 118a, 188b, it is appreciated that more than two ring support surfaces may be positioned on the radial collar 116. In some embodiments, each ring support surface 118a, 118b may hold a singular wear ring. In other embodiments, each ring support surface 118a, 118b may hold a plurality of wear rings. The ring support surfaces 118a, 118b can have a scalloped shape or groovelike structure. In some embodiments, the ring support surfaces 118a, 118b can face at least partially in an outward radial direction. In other embodiments, the ring support surfaces 1 18a, 1 18b can face at least partially in an outward radial direction and at least partially in an axial direction. Alternatively, in some embodiments, the ring support surfaces 1 18a, 118b may be oriented in an identical direction or different directions. In some embodiments, at least one ring support surface 118a, 1 18b may include an about 90-degree angled shoulder. In other embodiments still, the ring support surfaces 118a, 118b may be machined. Additionally, the ring support surfaces 1 18a, 118b may be oriented on the radial collar 116 near the tooth support surface 120. In other embodiments, the ring support surfaces 118a, 118b may be located at any location along the radial collar 1 16 and have a maximum combined axial thickness about equal to the axial thickness of the radial collar 116.

In some embodiments the interior surface of central bore 112 can be have a first hardness, the tooth support surface 120 can have a second hardness, the radial collar 116 can have a third hardness and the wear rings 122a, 122b can have a fourth hardness. In some embodiments, the wear rings 122a, 122b can have different hardnesses. In other embodiments still, the forward wear ring 122a can have a greater hardness than any trailing wear ring 122b. In other embodiments, the forward wear ring 122a can have a hardness less than any trailing wear ring 122b. In some embodiments, the interior surface of the central bore 112 and the tooth support surface 120 may have equal hardnesses. In other embodiments, the interior surface of the central bore 112 and the tooth support surface 120 may be induction hardened. In still other embodiments the wear rings 122a, 122b can have hardnesses greater than that of the radial collar 116, the tooth surface 120 and interior surface of the central bore 1 12. In still other embodiments, the wear rings 122a, 122b can have hardnesses greater than that of the radial collar 116, and less than that of the tooth support surface 120 and interior surface of the central bore 112. In the same embodiment, the radial collar 116 may have a hardness less than that of the tooth support surface 120 and the interior surface of the central bore 112. In some embodiments, the radial collar 1 16 can have a hardness between about 20HRC and about 30 HRC. In other embodiments, the tooth support surface 120 and the inner surface of the central bore 1 12 can have a hardness between about 50HRC and about 60HRC. In other embodiments still, the radial collar 116 and the shaft portion 114 can be of 4140 steel. In some embodiments the shaft 114 can have a length between about 3 inches and about 4 inches. In some embodiments, the central bore 112 may have an outer diameter between about 1.70 inches and about 1.75 inches. In other embodiments, the tooth support surface 120 can have a diameter between about 3 inches and about 4.5 inches. In other embodiments still, the wear ring 122 can have an outer diameter of about between about 3 inches and about 4.5 inches. In other embodiments, the shaft portion 114 can have an outer diameter between about 2.250 inches and about 2.260 inches.

The above specification, examples and data provide a complete description of the manufacture and use of the composition of the inventive aspects. Since many embodiments of the disclosure can be made without departing from the spirit and scope of the inventive aspects, the inventive aspects reside in the claims hereinafter appended.