The present invention relates to a wear member for use along the digging edge of an excavating machine.
Excavating equipment of all kinds and sizes include various wear members to protect the front digging edge from damage and wear. Wear members include points (or tips), adapters, shrouds, runners, and the like. These wear members are commonly subjected to highly abrasive materials and are used under arduous conditions. To withstand the rigors of digging, the wear members must be securely held to the excavating equipment to prevent their loss during use. Furthermore, to prevent ingress of the material being excavated into a gap between wear members, or between a wear member and a digging edge, it is desirable to have close fitting parts with as few gaps as possible. Nevertheless, due to the harsh environment, the parts frequently wear out and need replaced.
Replacing wear members can be difficult and dangerous for the personnel involved because it is usually a manual process and wear members can be heavy. Lifting hooks can be provided on the wear members to simplify the removal process; however, such lifting hooks are typically worn away by the time the wear member needs replaced.
It is among the objects of some embodiments to obviate or mitigate the above disadvantage or other disadvantages of prior art wear members or to provide a useful alternative.
The present invention relates to a wear member to protect the digging edge of excavating equipment, such as the lip of a bucket. The wear member includes a non-protruding lifting feature rearwards of a lock aperture so that it is not worn away during operation of the digging edge to which it is attached.
According to a first aspect there is provided a wear member comprising: an upper leg having a ground engaging surface on an outer side thereof and a mounting surface on an inner side thereof, and a lower leg spaced apart from the upper leg and also having a ground engaging surface on an outer side thereof and a mounting surface on an inner side thereof, the mounting surfaces defining a mounting cavity therebetween and the legs meeting at a front portion, the upper leg defining (i) a lock aperture therein, (ii) a rear edge, and (iii) a lifting feature located adjacent to and between the lock aperture and the rear edge; the lifting feature defining (a) a front surface lower than the upper leg ground engaging surface and being inclined relative thereto, (b) a lower support surface opposite the front surface, and (c) a rear engaging surface extending between the front surface and the lower support surface and being recessed relative to the rear edge; wherein the front surface, lower support surface, and rear engaging surface provide a narrowed portion around which a lifting device may be located for relocating the wear member.
The front surface may extend from the upper leg ground engaging surface and may be inclined relative thereto and away therefrom.
The front portion at which the legs meet may comprise a central portion.
The narrowed portion may be recessed (or non-protruding) relative to the upper leg ground engaging surface, the upper leg inner surface, and the rear edge.
The front surface may define a concave shape (when viewed parallel to the angle of inclination of the surface, or when view from above) such that a central portion thereof is further from the lock aperture than side portions thereof. The front surface may define a concave shape when viewed from above and when viewed from the front.
The lower support surface may be inclined relative to the front surface, and may diverge relative thereto, to provide a narrow edge near the lock aperture and an enlarged portion towards the rear edge.
The rear engaging surface may define a concave shape such that a central portion thereof is further from the rear edge than side portions thereof. The rear engaging surface may be inclined relative to the rear edge.
The front surface may include a wear indicator to indicate a wear level at which the lifting feature should not be used. The wear indicator may comprise a geometrical shape (a line, a circle, a square, or the like) or text (such as “safe to lift”) recessed into (or alternatively, protruding from) the front surface.
The ground engaging surfaces on the outer sides of the upper and lower legs may meet at a shroud front edge on the central portion.
The ground engaging surfaces may comprise an abrasion resistant material.
The wear member may comprise a point (also called a tip), an adapter (including an intermediate adapter), a shroud, a runner, or the like.
Where the wear member comprises a shroud, the rear engaging surface may be spaced from a lip of a digging edge of an excavating machine when the shroud is mounted thereto.
The lifting feature may be generally centrally located rearwards of the lock aperture.
The lifting feature may define a rounded (convex) leading edge (a lower rear edge) at the junction of the lower support surface and the rear engaging surface. This reduces the risk of a lifting device (hook, cable, rope, tape, strap, wires, or the like) being damaged or even severed by the lifting feature.
Preferably, the lock aperture receives a lock, or other securing or attaching mechanism, to secure the wear member to a base mounted on a digging edge of excavating equipment.
According to a second aspect there is provided a wear assembly comprising: (i) the wear member of the first aspect, (ii) a base on which the wear member is mounted, and (iii) a lock securing the wear member to the base.
According to a third aspect there is provided a wear assembly comprising: (i) a base; (ii) a wear member comprising an upper leg having a ground engaging surface on an outer side thereof and a mounting surface on an inner side thereof, the upper leg defining (a) a lock aperture therein, (b) a rear edge, and (c) a lifting feature located adjacent to and between the lock aperture and the rear edge; the lifting feature being recessed relative to the ground engaging surface, the mounting surface, and the rear edge; and (iii) a lock located within the lock aperture and operable to engage with both the base and a surface of the lock aperture to secure the wear member to the base.
The base may define a boss upstanding from an upper surface thereof, and the lock aperture may be located rearwardly of the boss, so that the lock bears against a rear surface of the boss when located within the lock aperture.
The lifting feature may define (a) a front surface lower than the upper leg ground engaging surface and being inclined relative thereto, (b) a lower support surface opposite the front surface, and (c) a rear engaging surface extending between the front surface and the lower support surface and being recessed relative to the rear edge.
According to a fourth aspect there is provided a wear member comprising an outer ground engaging surface defining a lock aperture in which a lock may be located, and a lifting feature adjacent the lock aperture, the lifting feature comprising a narrowed portion recessed (or non-protruding) relative to: the outer ground engaging surface, an inner surface, and a rear edge of the wear member.
The narrowed portion may be located centrally and rearward of the lock aperture.
According to a fifth aspect there is provided a wear member comprising: an upper leg having a ground engaging surface on an outer side thereof and a mounting surface on an inner side thereof, the upper leg defining (i) a lock aperture therein, (ii) a rear edge, and (iii) a lifting feature located adjacent to and between the lock aperture and the rear edge; the lifting feature being recessed relative to the ground engaging surface, the mounting surface, and the rear edge.
These aspects have a number of advantages. For example, by providing a non-protruding lifting feature, there is less likelihood of the lifting feature being worn away during use of the wear assembly.
By using a lifting feature adjacent the look aperture, access to the lifting feature can be provided via the lock aperture (once the lock has been removed), thereby ensuring that the lifting feature can be accessed when the wear assembly is fully coupled together.
By locating the lifting feature rearwards of the lock aperture, the outer engaging surface and the lock protect the lifting feature from excessive wear during use of the wear member. Ingress of excavated material is also reduced by locating the lifting feature rearwards of the lock aperture and beneath the upper surface.
In this application relative terms are used, such as front, rear, up, down, horizontal, vertical, etc., only for ease of the description and understanding of the embodiments, not by way of limitation.
These and other aspects will be apparent from the following specific description, given by way of example only, with reference will now be made to the accompanying drawings, in which:
Reference is first made to the Figures, which are various views of a wear assembly 10, according to one embodiment of the present invention, mounted on a lip 12 of a bucket (illustrated schematically with phantom lines 13 in
The lip 12 has five forwardly projecting noses 14 mounted thereto to receive a point (or tip) (not shown). The noses 14 and points (not shown) collectively define the excavating teeth that penetrate and break up the ground ahead of the bucket. The lip 12 further comprises four bases 16, each base 16 being provided between adjacent noses 14. The noses 14 and bases 16 extend from a ramp portion 18 (
The shroud 20 is a wear member that fits over a corresponding base 16 on the lip 12 of the excavating bucket 13, between the excavating teeth, to protect the bucket lip 12 and to direct the earthen material into the bucket 13. The shroud 20 is held in place on the base 16 by a lock 22. In this embodiment, the noses 14 and bases 16 are shown as being a cast part of the lip 12, but in other embodiments they could be attached as adapters or inserts, for example by welding or mechanical attachment. In any event, each shroud 20 is placed over a base 16 on the front edge of the lip 12 between noses 14, as illustrated in
The base 16 may comprise a harder wearing material than the remaining part of the lip 12 (or may have a hard wearing coating thereon) to resist wear caused by the shroud 20 during operation. Nevertheless, the other parts of the lip 12 are not necessarily softer than the base 16.
The wear assembly 10 comprises the shroud 20, the base 16 and the lock 22. The lock 22 (best seen in
Referring particularly to
Front surface 30 defines a slightly convex curved shape which curves about two generally perpendicular axes. In particular, front surface 30 is curved generally about a vertical axis so that it curves rearward as it approaches each respective side surface 34; and is also curved generally about a horizontal axis so that it also curves rearward as it approaches the upper surface 32, and a lower surface (not visible in the drawings) opposite the upper surface 32.
Shroud 20 includes a front-facing wearable portion 40 (
The upper leg 44 defines an outer wear surface 50 (also referred to as an upper ground engaging surface), and an inner coupling surface 52 (best seen in
The spaced apart legs 44, 46 converge at a front of the shroud 20 to a narrow front edge 58, at the center of which is defined a lifting hook 60 to assist in mounting the shroud 20 onto the base 16.
To reduce wear during use, the outer wear surfaces 50, 54 may comprise highly abrasion resistant material, or other hard wearing material, or may include a hardened layer on an outer portion thereof.
The outer wear surface 50 defines a raised central portion 61 dimensioned to accommodate the base boss 36 in an underside thereof.
The upper leg 44 (specifically, the raised central portion 61) defines a lock aperture 62 at an upper, central location. The upper leg 44 also defines an upper leg rear edge 63 (best seen in
A lifting feature 64 is defined by the upper leg 44 immediately adjacent to, and rearward of, the lock aperture 62.
In a similar way to how a conventional shroud is secured to a lip, the lock 22 is pivoted into an open position and inserted into the lock aperture 62. When inserted therein, the lock 22 engages with sidewalls defining the lock aperture 62 and extends below the upper leg 44 to abut the boss rear surface 38 (
The outer wear surface 50 defines a second (upper) lifting hook 66 that is used to move the shroud 20 into position on the base 16 during installation. Typically, the lifting hooks 60, 66 will be worn away during operation of the excavating bucket 13 because these hooks 60, 66 are exposed to the earthen material being excavated.
The lock aperture 62 is defined by a front wall 67, opposing sidewalls 68a,b extending from the front wall 67, and rear wall portions 69a,b, each extending from a respective opposing sidewall 68a,b generally parallel to the front wall 67.
The lifting feature 64 comprises a narrowed central portion 70, which is recessed from the upper ground engaging surface 50 (best seen in
A lower support surface 76 (
A rear engaging surface 80 (best seen in
The configuration of the calibrated wear indicator 86 is designed so that it functions as a wear indicator. In this embodiment, the depth and length of the recess 86 is selected based on the radius of the front edge 72, in particular, to alert a user that the front edge 72 has been worn down and presents a sharpened edge to any lifting strap or cable that would be used to engage the lifting feature 64.
In this embodiment, the calibrated recess 86 extends from the upper leg narrow strip 65 to near the front edge 72. It is expected that the front surface 84 will wear from the upper edge 82 towards the front edge 72 (i.e. the front edge 72 wearing later than the upper edge 82). In this embodiment, the calibrated recess 86 extends for 80% of the distance from the front of the upper leg narrow strip 65 to the front edge 72.
When the calibrated recess 86 is no longer visible, a user knows that it is no longer safe to use the lifting feature 64 to remove the shroud 20.
The lower support surface 76 also has a concave recess shape (relative to the adjacent parts of the inner coupling surface 52), when viewed from the rear (best seen in
The rear engaging surface 80 also has a concave recess shape (relative to the leg rear edge 63), when viewed from the top (best seen in
Reference is now made to
To locate the strap 90, the user first removes the lock 22. This ensures that the lock aperture 62 is available to provide easy access to the lifting feature 64. A user couples a first end of the strap 90 to a hoist (not shown) above the shroud 20. The user then threads the second end of the strap 90 under the front edge 72, beneath the lower support surface 76, up past the rear engaging surface 80, and up towards the hoist. The user then couples the second end of the strap 90 to the hoist (not shown). The user can then operate the hoist in a conventional manner to help remove the shroud 20 from the lip 12 in a safe manner.
It will now be appreciated that this embodiment has the advantage of providing an area on a shroud that can be used to lift the shroud away from the lip when the shroud needs to be replaced. Unlike conventional lifting hooks, the lifting feature is recessed from the ground engaging surface, protected by a lock used to secure the shroud to the lip (via the base), and located rearwards of the ground engaging end of the shroud, thereby reducing any wear that the lifting feature experiences so that it can be used even after the conventional lifting hooks have all worn away. When the lock is removed, easy access is provided to the lifting feature to simplify routing a lifting device around the lifting feature. The lock aperture allows for easy removal of fines or other debris prior to routing the lifting device around the lifting feature. By locating the lifting feature to the rear of the shroud behind the lock aperture, a low stress part of the shroud is being used to define the lifting feature and very little loading is expected on this area during the working life of the shroud.
Although the wear assembly is described in terms of a shroud secured to a lip, other wear members (e.g., adapters, points, wings, runners and the like) are included in the definition of wear member. Such other wear members may be secured to bucket lips or other excavating equipment.
Various modifications may be made to the above described embodiments within the scope of the present invention. For example, the base front surface 30 could be defined as a spherical segment, by curvatures that follow different paths, or by curvatures that vary; or could be formed with a generally planar configuration or curved about a single axis or axes extending in only one direction. In other embodiments, different shapes of the legs 44, 46 could be used instead of the shapes described above; in particular, to accommodate different lip shapes or different uses. In other embodiments, the outer wear surface 50 may not include a raised central portion 61. In other embodiments, the front surface 84 extends from between approximately 40% and 80% of the width of the adjacent lock aperture 62. In other embodiments a different shape or length of calibrated indicator 86 may be used. In other embodiments, the depth and width of the recess 86 may be selected based on the thickness of the narrowed central part 70. In other embodiments, the calibrated recess 86 may extend for between 50% and 90% of the distance from the upper leg narrow strip 65 to the front edge 72.
Number | Date | Country | |
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62970119 | Feb 2020 | US |