The present disclosure pertains to wear members for earth working equipment.
During mining and construction operations, replaceable teeth are commonly secured to earth working equipment for penetrating the ground and protecting the equipment, such as excavation buckets, from premature wear. The teeth are composed of wear members, such as an adapter and a point, that are held together by locks. During use, these wear members gradually wear down due to abrasive conditions and heavy loading. Once depleted, the wear members are removed from the equipment and replaced. Using such wear members provides a cost-effective approach to digging and other earth working operations because it lessens the need of having to repair or replace the more expensive underlying equipment such as the lip or other portions of the equipment.
Wear caps are at times installed on adapters to overlie surfaces subjected to high levels of wear to protect them and thereby increase their usable life. Wear caps are typically provided with a slot and are installed over a tongue formed on the wearable surface of the part to be protected. Wear caps, however, have also tended to possess various disadvantages such as imposing constraints on the design of the underlying part, being difficult to install or remove, causing reduced penetrability, and/or increasing manufacturing and/or inventory costs.
The present disclosure pertains to excavating teeth and, in particular, to wear members comprising the teeth.
In one example, wear caps protect the wearable surfaces of an adapter subjected to erosion by contact with abrasive material, such as experienced in an excavating operation. The wear caps can be attached to the inner and outer surfaces of an adapter to protect the adapter rearward of the nose. Each wear cap is secured to a wearable surface by an independent mounting structure even when a plurality of wear caps overlies the same inner or outer surface.
In one other example, a wear assembly includes an adapter including at least one leg, and first and second wear caps mounted on the leg at separate first and second mounting stations.
In another example, an adapter is provided with one or two identical wear caps on each leg of the adapter, wherein the wear caps are independently mounted and substantially cover both legs.
In another example, an adapter is provided with two wear caps on one leg and a single wear cap on its other leg, wherein the wear caps are identical, are all secured on independent mounting structures, and collectively substantially cover both legs of the adapter.
In another example, an adapter for a wear assembly has a top leg that includes a front attachment feature and a rear attachment feature spaced and separate from the front attachment feature wherein each attachment feature mounts a wear cap to the adapter.
In another example, an adapter includes top and bottom legs to straddle a lip wherein one or more wear cap covers at least half of one or both legs. In one other such example, one or more wear cap covers at least 70% of one or both legs. In another such example, a plurality of wear caps covers at least 70% of the top leg. In another such example, a single wear cap covers at least 70% of the bottom leg.
In another example, a wear assembly for earth working equipment includes an adapter having a forwardly projecting nose and an inner surface rearward of the nose, wherein the inner surface has at least two independent retention structures, a wear member having a cavity that receives the nose, a lock to secure the wear member to the adapter, and a wear cap mounted on each of the independent retention structures.
In another example, an adapter for mounting on a base of an earth working equipment includes a forwardly projecting nose for mounting a wear member, an inner leg to extend over the base, and an inner surface rearward of the nose, wherein the inner surface extends over the inner leg and has at least two independent retention structures for mounting wear caps.
In another example, an adapter includes at least one rearward tapering dovetail slot for mounting a wear cap to facilitate an easier installation and/or removal of the wear cap.
In another example, an adapter for a wear assembly includes a top leg of reduced thickness to accommodate the use of wear caps for longer life but with reduced impact on the tooth's overall thickness, ability to penetrate the ground, and/or loading or unloading of the bucket. In one such example, the maximum thickness of the top leg is less than 35% of the maximum thickness of the adapter forward of the lip. In another such example, the maximum thickness of the top leg is less than 30% of the maximum thickness of the adapter forward of the lip. In another such example, the maximum thickness of the top leg is about 26% (e.g. within a range of plus 25.5% to 26.5%) of the maximum thickness of the adapter forward of the lip.
In another example, the adapter has a rear section rearward of the front of the lip, which includes top and bottom legs to straddle the lip of a bucket, and a front section forward of the lip, which includes a nose to mount a point forward of the lip, wherein the rear section has a reduced increase in thickness over the front section to accommodate the use of wear caps for longer life but with reduced impact on the tooth's overall thickness, ability to penetrate the ground, and/or loading or unloading of the bucket. In one such example, the rear section has a maximum thickness that is less than 10% more than the maximum thickness of the front section. In another such example, the rear section has a maximum thickness that is less than 9% more than the maximum thickness of the front section. In one other such example, the rear section has a maximum thickness that is only about 8.5% more than the maximum thickness of the front section.
In another example, an adapter includes adjacent lifting holes passing through a top leg to receive a hook or other means for lifting the adapter. In one such example, the top leg receives a wear cap over the holes.
In another example, an adapter for mounting on a base of an earth working equipment includes a forwardly projecting nose for mounting a wear member, an inner leg to extend over the base, an inner surface facing away from the base, and at least one hole in the inner surface extending generally toward the base and configured to receive a lifting hook for lifting the adapter.
Excavating teeth are commonly secured to the digging edge of earth working equipment (e.g., a bucket) to improve digging and protect the equipment against premature wear. As an example, a tooth may include an adapter secured to a bucket, and a point secured to the adapter. Alternatively, a tooth may include an intermediate adapter fit between the adapter and the point. The adapter may be a component secured to the lip (by welding or otherwise) or may be an integral portion of a cast lip including a forwardly projecting nose. Although points generally wear faster, adapters are also subjected to loading and abrasive conditions such that both components are considered wear members that need replacement after a period of use; e.g., during use, these wear members gradually wear down due to the abrasive conditions and heavy loading. Once depleted, the wear members are removed from the equipment and replaced. Using such wear members provides a cost-effective approach to digging and other earth working operations because it generally results in a smaller amount of discarded material when parts are replaced and lessens the need of having to repair or replace the more expensive underlying equipment such as the lip.
Adapters can have a number of different forms and be attached in different ways. In the example of
Referring to the example illustrated in
The adapter 14, rearward of point 12, is substantially protected from wear by wear caps 16. The wear caps 16, 16′, 16″ are preferably identical though differences are possible. The use of identical wear caps 16, 16′, 16″ reduces manufacturing and inventory costs and eases their use in earth working operations (e.g., in a mine) by eliminating the prospect of mixing up similar looking wear caps. Moreover, the wear caps 16, 16′, 16″ and inner and outer surfaces 14F, 14G (and legs 14A, 14B) are cooperatively dimensioned so that identical wear caps 16, 16′, 16″ substantially cover both the inner and outer surfaces 14F, 14G as well as the top leg 14A and the bottom leg 14B; in the illustrated example, the inner and outer surfaces extend forward of the legs up to the nose.
One beneficial arrangement, as shown, includes two wear caps 16′, 16″ to substantially cover the inner surface 14F (and top leg 14A) and one wear cap 16 to substantially cover the outer surface 14G (and bottom leg 14B) to maximize the design of the legs 14A, 14B and minimize the number of required wear caps 16, 16′, 16″ where all three of the wear caps 16, 16′, 16″ are identical (
Each wear cap 16, 16′, 16″ is preferably secured to a discrete mounting station 18A, 20A, 22A to provide more flexibility in the leg design, and/or enable easier installation and/or removal of the wear caps 16, 16′, 16″. For example, in the illustrated example, the use of separate stations 18A, 20A, 22A enables the use of an adapter 14 with a slimmer profile (i.e., primarily using a thinner top leg) for better ground penetration, and less impediments to filling and dumping the bucket. The separate mounting stations in this example also permit the use of an easier and quicker installation and removal process for the wear caps 16, 16′, 16″ as compared to feeding successive wear caps along continuous (e.g., linear) rails or grooves formed in the adapter. In this example, top or inner leg 14A includes front and rear mounting stations 18A, 20A, and bottom or outer leg 14B includes mounting station 22A.
Referring to
Each mounting station 18A, 20A, 22A is centrally located and includes a front surface 38, a back surface 40, a retention feature 18, 20, 22 to complement and engage attachment features 16A for securing the wear caps 16, 16′, 16″ to the adapter 14. In the illustrated embodiment, the rearward mounting station 20A on inner surface 14C is staggered and oriented differently from mounting station 18A. More specifically, mounting station 20A is situated slightly above mounting station 18A and/or at somewhat different inclinations such that they do not align, so that they are independent of each other. Each wear cap is fit onto the adapter by engaging its particular mounting station without having to first traverse over a different mounting station. As an example, the wear cap 16′ is mounted on mounting station 20A without having to first traverse mounting station 18A.
The retention elements 18, 20, 22 each includes a forward-opening dovetail slot 25 having tapered side surfaces 34, 36, a bottom surface 25A, and a stop 42. The tapered side surfaces 34, 26 converge rearwardly. The stop 42 acts a barrier or end for the attachment feature 16A of the wear cap 16, 16′, 16″ and may further include stepped surfaces 42A. The stepped surfaces 42A are adjacent a sloped or curved surface 44 that connects the dovetail slot 25 to the back surface 40 of the retention feature 18, 20, 22. Adjacent the back surface 40 lies a mound surface 46. The mound surface 46 is adjacent an arched or curved surface 48, 48A. The length of the arched surfaces 48, 48A are from substantially the beginning of the dovetail slot 25 to the end of the mounting station 18A, 20A, 22A. The arched surfaces 48, 48A are adjacent the outer surface 45, 47. The arched surfaces 48, 48A may angle inward at the entrance of the dovetail slot 25 to aid in the introduction the attachment feature 16A of the wear cap 16, 16′, 16″. While this one example is disclosed, the mounting stations could have different kinds of retention elements.
The attachment feature 16A can be a male or female element to receive the other of a male or female element in the retention feature. As examples only, the attachment and retention features 16A, 18, 20, 22 can each have a tapered dovetail configuration as shown in
In an alternative, as seen in
In the example shown in
In the illustrated example, the rear wear cap 16′ is installed into mounting structure 20 first followed by the front wear cap 16″ into mounting structure 18. The front wear cap 16″, then, blocks the forward advance and release of the rear wear cap 16′, and the point 12 blocks the forward advance and release of the front wear cap 16′. The wear cap 16 on the lower leg 14B is similarly installed into mounting structure 22 and similarly held in position by the installed point 12. The configuration shown is an example.
One or more of the wear caps 16, 16′, 16″ could alternatively be secured by a lock or other mechanical means. The attachment features 16A are preferably formed (e.g., by casting) in place with the component, but they could be welded or otherwise secured to the component.
The attachment features 16A in the example of
As seen in
As noted above, the wear caps 16, 16′, 16″ preferably substantially cover both legs 14A, 14B of the adapter 14, which in this application means the wear caps 16, 16′, 16″ extend over 50% of the lengths L3, L4 of the inner and outer surfaces 14F, 14G and/or the lengths L1, L2 of the legs 14A, 14B. The wear cap(s) 16, 16′, 16″ preferably extend over 70% of the lengths L3, L4 of the inner and outer surfaces 14F, 14G and/or the lengths L1, L2 of each leg 14A, 14B. The inner surface 14F is shown with two wear caps 16′, 16″. Alternatively, the inner surface 14F can receive more or fewer wear caps. The outer surface 14G is shown with one wear cap 16. Alternatively, the outer surface 14G can have a similar configuration as the inner surface receiving multiple wear caps.
The preferred attachment features 16A and/or use of discrete mounting stations 18A, 20A, 22A can lead to a slimmer adapter 14, which can result in lower costs, less weight, better penetration and/or less stress concentration. In one such example shown in
In one such example, a thickness T1 is measured from the bottom of the inner leg 14A to a lowest point of the curved surface 44. A maximum thickness T1 of the inner leg 14A is less than 35% of the maximum thickness T3 of the adapter 14 forward of the lip 8. In another such example, the maximum thickness T1 of the inner leg 14A is less than 30% of the maximum thickness T3 of the adapter 14 forward of the lip 8. In another such example, the maximum thickness T1 of the inner leg 14A is about 26% (e.g. within a range of plus 25.5% to 26.5%) of the maximum thickness T3 of the adapter 14 forward of the lip 8.
The slimmer profile may be part of an overall design such that the overall thickness of the legs 14A, 14B is reduced compared to conventional adapters. The adapter 14 has a rear section 49 rearward of the front 33 of the lip 8 (i.e., rearward of the datum 39 aligned with the designated location of front surface 33), which includes top and bottom legs 14A, 14B to straddle the lip 8 of a bucket, and a front section 51 forward of the lip 8 (i.e., forward of the datum 39), which includes a nose 14E to mount a point 12 forward of the lip 8.
In one such example with a slimmer profile, the rear section 49 has a reduced increase in thickness over the front section 51 to accommodate the use of wear caps 16′, 16″ for longer life but with reduced impact on the tooth's overall thickness, ability to penetrate the ground, and/or loading or unloading of the bucket. In one such example, the rear section 49 has a maximum thickness T4 that is less than 10% more than the maximum thickness T3 of the front section 51. In another such example, the rear section 49 has a maximum thickness T4 that is less than 9% more than the maximum thickness T3 of the front section 51. In one other such example, the rear section 49 has a maximum thickness T4 that is only about 8.5% more than the maximum thickness T3 of the front section 51.
Adapters can be heavy. As a result, conventional adapters may be provided with a lifting eye extending from the top leg to receive a hook or clevis to support the member during installation. The lifting eyes can be troublesome to cast and securing the lifting eyes by welding can increase costs, reliability and/or the toughness of the steel. Moreover, at the end of service life, these eyes are typically worn away. In the illustrated example, adapter 14 includes a two adjacent openings 24 and 26 passing through top leg 14A and generally extending toward the base, though one hole with an undercut could be used. These holes 24, 26 are sized to receive a hook or other lifting tool to support the adapter by a crane and cable or other method during installation and removal. The use of these holes 24, 26 as opposed to a conventional protruding lifting eye can be easier to manufacture than conventional lifting eyes and will likely still be accessible at the time of removal from the lip 8. The use of such lifting holes 24, 26 can also facilitate broader coverage of the adapter legs 14A, 14B with wear caps 16, 16′, 16″ and lead to a greater service life. As can be seen in
Referring to
In another alternative, the intermediate adapter 214 may include a set of two mounting structures on the upper leg and one on the lower leg as is previously described. This configuration may also include the base adapter having wear caps and mounting structures as previously described above. It is also foreseen that an integral portion of a cast lip including a set of mounting structures for two identical, aligned, and staggered wear caps.
The wear caps and wear assemblies presented here provide improved protection to limit erosion of critical components extending their service life and reducing downtime to replace components. It should be appreciated that although selected examples of the representative wear caps are disclosed herein, numerous variations of these examples may be envisioned by one of ordinary skill that do not deviate from the scope of the present disclosure. This presently disclosed wear assemblies lend themselves to use with many different configurations of wear caps.
This disclosure encompasses multiple distinct inventions with independent utility. The various features of the invention described above are preferably included in each assembly. Nevertheless, the features can be used individually in a wear assembly to obtain some benefits of the invention. While each of these inventions has been disclosed in its preferred form, the specific examples thereof as disclosed and illustrated herein are not to be considered in a limiting sense as numerous variations are possible. Each example defines an example disclosed in the foregoing disclosure, but any one example does not necessarily encompass all features or combinations that may be eventually claimed. Where the description recites “a” or “a first” element or the equivalent thereof, such description includes one or more such elements, neither requiring nor excluding two or more such elements. Further, ordinal indicators, such as first, second or third, for identified elements are used to distinguish between the elements, and do not indicate a required or limited number of such elements, and do not indicate a particular position or order of such elements unless otherwise specifically stated.
This application claims the benefit of priority from U.S. Provisional Patent Application No. 62/803,317, filed Feb. 8, 2019, the entirety of which is incorporated by reference.
Number | Date | Country | |
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62803317 | Feb 2019 | US |