Patent Application
20180058034
The present disclosure relates to the shell design of buckets used to move material such as dirt, stone, coal and the like. More particularly, the present disclosure is related to a shell profile design that uses multiple components.
Buckets are well known in the art for moving material such as dirt, stone, coal, etc. In some instances, material, especially re-handled coal, does not evacuate from the bucket properly during a dumping operation. This is often attributed to sticking of the material such as coal in the corners of the bucket. This reduces the productivity of a mining, construction or similar endeavor and may also increase the amount of fuel used during these types of operations as the material packs into the bucket, adding weight to the bucket undesirably. More specifically, in a coal handling application, the increased fuel burn occurs as the packed coal is transported back from the intended destination, such as a hopper, to the origin of the coal, such as the pile of the coal.
A bucket assembly is provided that may comprise a multi-component shell subassembly including an at least partially curved member that defines a first transverse end, a second transverse end, a top edge and a bottom flat portion. The assembly may also comprise a first flat angled plate attached to the first transverse end of the curved member and a second flat angled plate attached to the second transverse end of the curved member and a rear plate that is attached to the top edge of the curved member of the shell subassembly. A bottom plate may be attached to the bottom flat portion of the curved member of the shell subassembly.
A bucket assembly is provided that may include a multi-component shell subassembly including an at least partially curved member that defines a first transverse end, a second transverse end, a top edge and a bottom flat portion, and a first flat angled plate attached to the first transverse end of the curved member and a second flat angled plate attached to a second transverse end of the curved member, wherein the curved member defines a first thickness and either the first angled flat plate or second angled flat plate defines a second thickness, wherein the second thickness is less than the first thickness.
A bucket is provided that may comprise a shell including an at least partially curved member that defines a first transverse end, a second transverse end, a top edge and a bottom flat portion. The bucket may also include a first flat angled member attached to the first transverse end of the curved member and a second flat angled member attached to a second transverse end of the curved member, a bottom member that is attached to the bottom flat portion of the curved member of the shell subassembly, and at least one attachment bracket, wherein the bucket assembly defines a bucket center plane and the first and second flat angled members are tapered toward the center plane of the bucket.
Reference will now be made in detail to embodiments of the disclosure, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. In some cases, a reference number will be indicated in this specification and the drawings will show the reference number followed by a letter for example, 100a, 100b or a prime indicator such as 100′, 100″ etc. It is to be understood that the use of letters or primes immediately after a reference number indicates that these features are similarly shaped and have similar function as is often the case when geometry is mirrored about a plane of symmetry. For ease of explanation in this specification, letters or primes will often not be included herein but may be shown in the drawings to indicate duplications of features discussed within this written specification.
This disclosure provides various embodiments of bucket assemblies that include the following features. In some embodiments, a new three piece shell profile is applied to shape the rear corners of the bucket in a manner which easily releases the material. That is to say, tight corners are reduced to prevent material packing. Material packed in the corners causes reduced productivity and increased fuel burn by carrying back material from the destination (hopper) back to the origin (pile) as previously mentioned. Additionally, in some embodiments, a thinner plate is applied to replace a traditionally thicker material in this area which results in a bucket weight reduction. The reduced bucket weight allows for a larger bucket to be designed to move more payload, resulting in better productivity for the customer. A third set of embodiments focus on the outside of the bucket shape. The cropped corners reduce drag on the bucket when entering the pile. The reduced drag forces can be transferred back to the cutting edge where they contribute to additional loading of material in the bucket and increased productivity. In the case of a full bucket, the reduced drag will improve fuel efficiency when sweeping through the pile, etc.
Looking at
At least one flat angled plate 230 forms a first acute angle α with the bottom plate 208, wherein said angle is projected onto the bottom plate 208 along a direction that is perpendicular to the bottom plate 208. This same flat angled plate may form a second acute angle β with the bottom plate 208, wherein said angle is projected onto a plane that is perpendicular to the bottom plate 208 along a direction that is parallel to the bottom plate 208 and perpendicular to an end plate 114. The first acute angle α may range from 30 to 85 degrees while the second acute angle β may range from 5 to 75 degrees.
Continuing to refer to
The assembly 200 of
As best seen in
Looking at
In some embodiments, the first thickness T220 may range from 6 to 30 mm while the second thickness T230 may range from 4 to 25 mm. In an exemplary embodiment, the first thickness T220 may be about 25 mm and the second thickness T230 may be about 16 mm. A desired ratio of the first thickness T220 to the second thickness T230 may range from 1 to 3.
The assembly 200 may further comprise a rear wall 206 that is attached to the top edge 226 of the curved member 220 of the shell subassembly 204, a bottom plate 208 that is attached to the bottom flat portion 228 of the curved member 220 of the shell subassembly 204, and a spill guard 212 that is attached to the top plate 210. In addition, the assembly 200 may comprise at least one end plate 214 that is attached to each of the following: the rear plate 206, the curved member 220 of the shell subassembly 204, the spill guard 212, at least one flat angled plate 230 and the bottom plate 208. These various attachments may form at least one point of intersection 232 where the curved member 220, flat angled plate 230 and end plate meet 214.
As best seen in
As also previously discussed with reference to
Referring now to
The first and second angled flat plates 230, 230′ may form a compound angle γ with the bottom plate 208 that is formed by tapering the corners 240 of the bucket assembly toward the center plane (Y-Z plane) of the bucket when the bucket is arranged in its most upward extent when attached to a machine. This position is depicted in
As mentioned earlier herein with reference to
Likewise, the curved member 220 may define a first thickness T220 and either the first angled flat plate or second angled flat plate 230 defines a second thickness T230, wherein the second thickness is less than the first thickness. The reasons for this difference in thickness will be explained more thoroughly later herein.
The assembly 200 typically also comprises at least one end plate 214 that is attached to each of the following: the rear plate 206, the curved member 220 of the shell subassembly 204, at least one flat angled plate 230, and the bottom plate 208, forming at least one point of intersection 232 where the curved member, flat angled plate and end plate meet. In this embodiment as best seen in
Other constructions of any of the embodiments discussed herein are possible including those with more or fewer components than have been explicitly described herein. For example, the assembly may be made unitary using a casting process. In which case, disparate members may be integrally formed with each other. In such a case, the terms “plate” or “wall”, etc., may be replaced by the term “member”, etc. Also, the “bucket assembly” may simply be referred to as a “bucket”. This variance of the construction of the bucket may be applied to any of the embodiments discussed herein.
In practice, a bucket or bucket assembly may be sold, manufactured, bought or otherwise provided according to any of the embodiments described herein. In some applications, a bucket subassembly may be retrofitted or repaired with a shell subassembly according to any of the embodiments described herein. The parts and/or subassemblies needed for retrofitting or repairing may be sold, manufactured, bought or otherwise provided.
Any of the bucket assemblies as described herein may be attached to a work machine using a coupling mechanism that is now known or that will be devised in the art using attachment brackets, etc.
A method for designing and fabricating a bucket that is less prone to have material stick to its interior will now be described. Empirical or experimental evidence may be ascertained from buckets used to move material such as coal and the like. Over time, material may stick in the bucket due to compaction as has already been described. The stuck material may define a slip plane that indicates when the material is naturally prone to disengage or release and fall out of the bucket. The bucket may then be designed and fabricated with an angled plate that approximately matches this slip plane. This slip plane may vary depending on the shape of the bucket and type of material being used. Consequently, the specific design including the angles at which the corners of the bucket are cropped may vary from the values explicitly described herein but are to be considered within the scope of the present disclosure.
Similarly, a method for designing and fabricating a bucket that is less prone to wear may be describe as follows. Measurement of the wear of a bucket may be experimentally or empirically derived. Those areas subject to the most wear may be eliminated by cropping or altering the shape of the bucket to remove those areas. This may also reduce the drag on the bucket, improving the machine efficiency as already described.
In many embodiments, the sticking, wear and energy efficiency performances may be improved simultaneously by combining the designs optimized using both the methods just described. Indeed, in many applications the results of the design optimization involving both methods may greatly overlap as was the case for the embodiments explicitly described herein. This may not be true for other embodiments.
Finally,
As can be seen, the areas with the greatest amount of wear were located in the rear corner of the bucket 300 (see points I-L). The inventor then proceeded to optimize the shape of the bucket based on this data. The center of the bucket 300 was left essentially alone compared to previous designs as this area experienced the least amount of wear. Also, the middle portion of the bucket experiences the heaviest forces as the insertion or cutting force of the front edge assembly 304 is naturally prone to be conveyed to the center of the bucket where the attachment brackets 306 are located. Maintaining a thicker section here helps to support this load. On the other hand, the back corner of the bucket 300 receives very little of this load. Therefore, its design may be adjusted to be only be thick enough as needed to support the weight of the material when the bucket 300 is fully loaded. This explains why the angled plates are thinner than the middle portion of the shell.
The front of the side or end plate 308 (see points E-F) did not experience much wear. So, it did not need to be modified. However, this rear corner (see points I-L) experienced as much as 3-5 times as much wear as portions of the middle of the bucket, so by eliminating it, the wear and energy performances were improved. Also, by angling the back corner properly, the sticking performance of the bucket was also improved.
It should be noted that wings 310 are provided on this style of bucket 300. This wings 310 are intended to protect the tires of the machine from damage when moving rocks and stone, etc. These wings protect the portions of the bucket immediately behind them. This likely skewed the wear results for point M. For applications such as those discussed herein where coal is moved and such wings are not used or deemed necessary, one skilled in the art would expect point M to experience a higher rate of wear. Consequently, the inventor took this in consideration when angling the back corner of the buckets explicitly described herein.
While various embodiments have been described to be well suited for different applications and performance improvements, it is to be understood that many of the embodiments discussed herein may be able to improve performances other than those specifically mentioned regarding those embodiments.
It will be appreciated that the foregoing description provides examples of the disclosed assembly and technique. However, it is contemplated that other implementations of the disclosure may differ in detail from the foregoing examples. All references to the disclosure or examples thereof are intended to reference the particular example being discussed at that point and are not intended to imply any limitation as to the scope of the disclosure more generally. All language of distinction and disparagement with respect to certain features is intended to indicate a lack of preference for those features, but not to exclude such from the scope of the disclosure entirely unless otherwise indicated.
Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein.
It will be apparent to those skilled in the art that various modifications and variations can be made to the embodiments of the apparatus and methods of assembly as discussed herein without departing from the scope or spirit of the disclosure(s). Other embodiments of this disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the various embodiments disclosed herein. For example, some of the equipment may be constructed and function differently than what has been described herein and certain steps of any method may be omitted, performed in an order that is different than what has been specifically mentioned or in some cases performed simultaneously or in sub-steps. Furthermore, variations or modifications to certain aspects or features of various embodiments may be made to create further embodiments and features and aspects of various embodiments may be added to or substituted for other features or aspects of other embodiments in order to provide still further embodiments.
Accordingly, this disclosure includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the disclosure unless otherwise indicated herein or otherwise clearly contradicted by context.
