Patent Description:
Gyratory crushers comprise a mainshaft assembly which rests within a lined eccentric. During routine maintenance of such crushers, it is required to periodically remove the mainshaft assembly to gain access to internals, service the mainshaft assembly, or service other components within the crusher.

Difficulties exist in aligning the mainshaft assembly upon reintroduction of the same into the gyratory crusher. This is, in part, because the axial line of the mainshaft and the rotation axis line of the eccentric bushing are not parallel. Instead, the lines intersect at a so-called "pivot point" which typically is located above the crushing surfaces.

Present methods for removing the main shaft assembly generally do not involve much risk of personal injury when performed in accordance with specified procedures. However, present methods of re-installing the mainshaft assembly back into the gyratory crusher involve significant risk of injuries - since operators must work underneath an overhead suspended main shaft assembly (which can weigh as much as <NUM> tons) to guide the mainshaft into place and prevent seals from being compromised.

During conventional mainshaft installation, personnel guide the mainshaft assembly manually into the offset/off-kilter eccentric bushing. In some gyratory crushers, personnel may also have to manually guide a seal located on the main shaft into a sealing sleeve bore while working underneath the mainshaft assembly.

Any failure of the lifting equipment, the crane, cable or lifting hook or erroneous crane operation might risk serious or fatal injury to the operator below. Pinch point hazards also exist during the process.

It is therefore desired to carry out mainshaft assembly installation in a manner which mitigates risk for the operators involved. In particular, there is a need to obviate the need to place maintenance personnel below a mainshaft assembly for purposes of guiding a distal end of the mainshaft assembly into an eccentric. There further exists a need to obviate the requirement of manual intervention to ensure seals are not compromised (e.g., bent, folded, jammed, caught, impinged) upon introduction of a mainshaft assembly into a gyratory crusher. <CIT>, <CIT>, <CIT> are made of reference herewith as related prior art.

<CIT> discloses a method for assembling a gyratory crusher (<NUM>) where a main shaft arrangement (<NUM>) having a main shaft (<NUM>) with a midmost axial portion enclosed by a first crushing surface (<NUM>) is lowered axially from a free-hanging position down into a centrally positioned bushing (<NUM>) which provides guidance and support for the main shaft (<NUM>) where at least a portion of the bushing (<NUM>) is located below the first crushing surface (<NUM>) which is configured for interaction with an opposite second crushing surface (<NUM>).

<CIT> relates to a cone crusher includes a stationary main shaft and an eccentric that rotates about the main shaft to cause gyrational movement of a head assembly to crush rock within a crushing gap.

<CIT> relates to a bearing supporting system for cone crushers of the type which has a head center securely mounted on an upper portion of a main shaft for mounting a mantle thereon and has the main shaft supported by the eccentric drive shaft in radial direction, the support system including a self-aligning thrust bearing mounted on an intermediate portion of the mantle shaft, supporting the main shaft on the eccentric drive shaft through the thrust bearing.

It is, therefore, an objective of the invention to circumvent the aforementioned dangers associated with prior art gyratory crusher devices.

It is also an objective of embodiments to provide a safer method for installing a mainshaft assembly into a gyratory crusher through the provision of self-alignment means for minimizing human exposure to danger and unnecessary risk. It is a further objective of embodiments to provide a quick, cost-effective, and efficient manner in which to introduce a distal end of a mainshaft assembly into a lined eccentric.

This and other objects of the invention will be apparent from the drawings and description herein. Although every object of the invention is believed to be attained by at least one embodiment of the invention, there is not necessarily any one embodiment of the invention that achieves all of the objects of the invention.

Disclosed, is an annular dust bonnet (<NUM>) for a gyratory crusher (<NUM>). The dust bonnet (<NUM>) is configured to facilitate alignment between a mainshaft assembly (<NUM>) and a bore (<NUM>) of an eccentric (<NUM>) or eccentric liner (<NUM>) upon the introduction of the mainshaft assembly (<NUM>) into the gyratory crusher (<NUM>); by lowering the mainshaft assembly (<NUM>) from above the gyratory crusher (<NUM>) into the gyratory crusher (<NUM>). The dust bonnet (<NUM>) comprises an inner sidewall (<NUM>) configured for receiving a lower mainshaft (<NUM>) of the mainshaft assembly (<NUM>) therethrough, and an outer sidewall (<NUM>) configured for engaging an annular dust seal (<NUM>) provided within the mainshaft assembly (<NUM>).

The dust bonnet (<NUM>) comprises a plurality of guides (<NUM>) arranged radially-inwardly with respect to the inner sidewall (<NUM>). Each of the plurality of guides (<NUM>) has a guiding surface (<NUM>') configured to contact the mainshaft assembly (<NUM>). The guiding surface (<NUM>') forms an angle (<NUM>) with respect to the inner sidewall (<NUM>), such that a lower portion of each guiding surface (<NUM>') is positioned further radially-inwardly with respect to the inner sidewall (<NUM>) than a respective upper portion of each guiding surface (<NUM>'). The guides (<NUM>) is collectively arranged and/or configured to bias the lower mainshaft (<NUM>) into concentric alignment with the bore (<NUM>); when the mainshaft assembly (<NUM>) is lowered into the gyratory crusher (<NUM>), without limitation.

The dust bonnet (<NUM>) comprises a plurality of guide mounts (<NUM>) provided to the inner sidewall (<NUM>). Each of the guide mounts (<NUM>) may be configured to support and supporting a respective one of said guides (<NUM>);in at least a radial direction.

According to some embodiments, each of the guide mounts (<NUM>) may extend radially-inwardly from the inner sidewall (<NUM>), without limitation.

According to some embodiments, each of the guides (<NUM>) may be removably affixed to one of the guide mounts (<NUM>). For example, one or more fasteners (<NUM>, <NUM>) may extend through one or more apertures (<NUM>, <NUM>) of each guide (<NUM>) and into its respective guide mount (<NUM>), without limitation.

According to some embodiments, each of the guide mounts (<NUM>) may comprise an inclined base surface (<NUM>). The inclined base surface (<NUM>) may be configured for supporting its respective one of said guides (<NUM>), without limitation.

According to some embodiments, each of the guide mounts (<NUM>) may comprise side rails (<NUM>). The side rails (<NUM>) may protrude further radially-inwardly than the inclined base surface (<NUM>), without limitation.

According to some embodiments, the side rails (<NUM>) may be configured to provide lateral support for the guides (<NUM>). The side rails (<NUM>) may alternatively or additionally facilitate positioning of the guides (<NUM>) with respect to their respective guide mounts (<NUM>), without limitation. The side rails (<NUM>) may comprise one or more side apertures (<NUM>) for receiving side pins (<NUM>) or other fasteners or fastening means to secure guides (<NUM>) to guide mounts (<NUM>), without limitation.

The dust bonnet comprises a lower sidewall (<NUM>). The lower sidewall extends radially inwardly with respect to the inner sidewall (<NUM>). The lower sidewall (<NUM>) forms an inner annular lip or inner annular flange proximate a lower portion of the dust bonnet (<NUM>). The guide mounts (<NUM>) is generally configured as triangular prisms or gussets, without limitation.

According to some embodiments, the inclined base surface (<NUM>) may extend at an angle (<NUM>) between the inner sidewall (<NUM>) and lower sidewall (<NUM>), relative to the inner sidewall (<NUM>), without limitation.

According to some embodiments, the dust bonnet (<NUM>) may comprise an annular upper radially-outer chamfer (<NUM>). The upper radially-outer chamfer (<NUM>) may be located proximate an upper rim of the dust bonnet (<NUM>), without limitation. The upper radially-outer chamfer (<NUM>) may be configured to engage a complementary annular lower radially-inner chamfer (<NUM>) of a dust seal (<NUM>), without limitation. The upper radially-outer chamfer (<NUM>) may be configured to bias the dust seal (<NUM>) into concentric alignment with the dust bonnet (<NUM>). The upper radially-outer chamfer (<NUM>) may be configured to guide the dust seal (<NUM>) over an outer surface (<NUM>) of the dust bonnet (<NUM>) when the mainshaft assembly (<NUM>) is lowered into the gyratory crusher (<NUM>), without limitation.

According to some embodiments, the guides (<NUM>) may be configured to bias the lower mainshaft (<NUM>) into concentric alignment with one or more annular oil seals (<NUM>); for example, one or more annular oil seals (<NUM>) which may be located below the guides (<NUM>). This may be accomplished, for example, by virtue of sliding contact with the lower mainshaft (<NUM>) (e.g., sliding contact between guide surfaces <NUM>' and outer surfaces of mainshaft (<NUM>) - including surfaces of an end plate (<NUM>) provided thereto), when the mainshaft assembly (<NUM>) is lowered into the gyratory crusher (<NUM>), without limitation.

An end plate (<NUM>) for provision to a lower distal end of a mainshaft assembly (<NUM>) of a gyratory crusher (<NUM>) is further disclosed. The end plate (<NUM>) may comprise a lower side and an upper side. The lower side may be configured to rest on a thrust bearing (<NUM>) (e.g., located above a hydraulic cylinder (<NUM>)), without limitation. The upper side of the end plate (<NUM>) may be configured to be received in a recess (<NUM>) (e.g., provided in a lower mainshaft (<NUM>) of the mainshaft assembly (<NUM>)), without limitation. The recess (<NUM>) may be defined by a bottom surface (<NUM>) of the lower mainshaft (<NUM>) which may be surrounded by a lower annular projection (<NUM>) of the lower mainshaft (<NUM>), without limitation.

The end plate (<NUM>) may be configured to bias a lower mainshaft (<NUM>) of the mainshaft assembly (<NUM>) into concentric alignment with a bore (<NUM>) of an eccentric (<NUM>) or eccentric liner (<NUM>); for example, upon the introduction of the mainshaft assembly (<NUM>) into the gyratory crusher (<NUM>) by lowering the mainshaft assembly (<NUM>) from above the gyratory crusher (<NUM>) into the gyratory crusher (<NUM>). This may be accomplished, for example, by virtue of a lower alignment chamfer (<NUM>) being provided to the end plate (<NUM>) at its radially-outermost periphery. The lower alignment chamfer (<NUM>) may be configured to synergistically work with guide surfaces (<NUM>') of guides (<NUM>), without limitation.

According to some embodiments, the end plate (<NUM>) may be configured to bias the lower mainshaft (<NUM>) of the mainshaft assembly (<NUM>) into concentric alignment with one or more annular oil seals (<NUM>) configured to surround the lower mainshaft (<NUM>) of the mainshaft assembly (<NUM>); for example, upon the introduction of the mainshaft assembly (<NUM>) into the gyratory crusher (<NUM>) by lowering the mainshaft assembly (<NUM>) from above the gyratory crusher (<NUM>) into the gyratory crusher (<NUM>), without limitation.

According to some embodiments, the lower alignment chamfer (<NUM>) may be configured to smoothly transition to a lower alignment chamfer (<NUM>) which may be provided proximate to the lower annular projection (<NUM>) of the lower mainshaft (<NUM>).

According to some embodiments, the end plate (<NUM>) may comprise an upper annular lip (<NUM>). The upper annular lip (<NUM>) may surround an upper projection (<NUM>) provided to the end plate (<NUM>). The upper annular lip (<NUM>) may be configured to seat against a lower surface of the lower annular projection (<NUM>) of the mainshaft assembly (<NUM>), without limitation.

According to some embodiments, the upper projection (<NUM>) may be configured to be received in the recess (<NUM>) provided in the lower mainshaft (<NUM>), without limitation.

According to some embodiments, an upper surface of the upper projection (<NUM>) may be configured to seat against the bottom surface (<NUM>) of the of the lower mainshaft (<NUM>), without limitatoin.

According to some embodiments, the upper annular lip (<NUM>) may intersect the lower annular chamfer (<NUM>) to form a top annular edge (<NUM>); e.g., at the widest part of the end plate (<NUM>), without limitation.

According to some embodiments, the lower alignment chamfer (<NUM>) may be configured to blend with the lower alignment chamfer (<NUM>) provided proximate the lower annular projection (<NUM>) of the lower mainshaft (<NUM>), without limitation. The two lower alignment chamfers (<NUM>, <NUM>) may blend together such that the lower alignment chamfer (<NUM>) of the end plate (<NUM>) is flush with the lower alignment chamfer (<NUM>) , without limitation. The two lower alignment chamfers (<NUM>, <NUM>) may blend together such that the lower alignment chamfer (<NUM>) shares the same (or similar) taper angle with lower alignment chamfer (<NUM>), without limitation.

A counterweight (<NUM>) for a gyratory crusher (<NUM>) is also disclosed. The counterweight may be adapted for provision to an upper portion of an eccentric (<NUM>) and/or eccentric liner (<NUM>) within the gyratory crusher (<NUM>). The counterweight (<NUM>) may have an upper side and an underside. According to some embodiments, the counterweight (<NUM>) may comprise a unique C-shaped arcuate profile having two ends. The counterweight (<NUM>) may also comprise a concave alignment chamfer (<NUM>).

The alignment chamfer (<NUM>) may be defined by a ramped surface which faces upwardly and radially-inwardly (with respect to the c-shaped arcuate profile, eccentric (<NUM>), and/or liner (<NUM>)). The ramped surface defining the alignment chamfer (<NUM>) may extend between the upper side and the underside of the counterweight. The ramped surface may extend between the two ends of the C-shaped arcuate profile. Accordingly, the counterweight (<NUM>) may be narrower in width across its upper side than across its underside, without limitation.

According to some embodiments, the alignment chamfer (<NUM>) may be configured to bias a lower mainshaft (<NUM>) of a mainshaft assembly (<NUM>) of the gyratory crusher (<NUM>) into concentric alignment with a bore (<NUM>) of the eccentric (<NUM>) or eccentric liner (<NUM>) to which it is provided; for example, upon the introduction of the mainshaft assembly (<NUM>) into the gyratory crusher (<NUM>) by lowering the mainshaft assembly (<NUM>) from above the gyratory crusher (<NUM>) into the gyratory crusher (<NUM>), without limitation.

According to some embodiments, the counterweight (<NUM>) may comprise projections (<NUM>) on the underside of the counterweight (<NUM>), without limitation.

According to some embodiments, the counterweight (<NUM>) may comprise mounting holes (<NUM>). The mounting holes (<NUM>) may extend through the counterweight (<NUM>) and be configured to secure the counterweight (<NUM>) to the eccentric (<NUM>) and/or eccentric liner (<NUM>), without limitation. For example, the mounting holes (<NUM>) may be configured to secure the counterweight (<NUM>) to an upper portion of an eccentric (<NUM>) and/or eccentric liner (<NUM>).

According to some embodiments, at least one of the mounting holes (<NUM>) may pass through one of the projections (<NUM>), without limitation. In some embodiments all mounting holes (<NUM>) may pass through respective projections (<NUM>), without limitation.

A gyratory crusher (<NUM>) can benefit from the above apparatus. For example, a gyratory crusher (<NUM>) according to some embodiments may comprise the dust bonnet (<NUM>) described above, the end plate (<NUM>) described above, or the counterweight (<NUM>) described above. In some embodiments, the gyratory crusher (<NUM>) may comprise the dust bonnet (<NUM>) described above in combination with the end plate (<NUM>) or counterweight (<NUM>) described above. In some embodiments, the gyratory crusher (<NUM>) may comprise the end plate (<NUM>) and
counterweight (<NUM>) described above. In some embodiments, all three of the dust bonnet (<NUM>), end plate (<NUM>) and counterweight (<NUM>) described above may be provided to the gyratory crusher, without limitation.

To complement the description which is being made, and for the purpose of aiding to better understand the features of the invention, a set of drawings illustrating new and novel methods and apparatus for assisting self-centering and alignment during mainshaft assembly <NUM> installation is attached to the present specification as an integral part thereof, in which the following has been depicted with an illustrative and non-limiting character. It should be understood that like reference numbers used in the drawings (if any are used) may identify like components.

In the following, the invention will be described in more detail with reference to drawings in conjunction with exemplary embodiments.

While the present invention has been described herein using exemplary embodiments of a gyratory crusher <NUM> and method of assembling the same, it should be understood that numerous variations and adaptations will be apparent to those of ordinary skill in the field from the teachings provided herein.

The detailed embodiments shown and described in the text and figures should not be construed as limiting in scope; rather, all provided embodiments should be considered to be exemplary in nature. Accordingly, this invention is only limited by the appended claims.

The inventors have recognized a novel and heretofore unappreciated gyratory crusher <NUM> which includes features which are configured to assist centering of a mainshaft assembly <NUM> upon the introduction of the same, without limitation. For example, novel features described herein are configured to promote self-centering and/or self-aligning when lowering a portion (e.g., lower mainshaft <NUM>) of the mainshaft assembly <NUM> into a liner <NUM> of an eccentric <NUM>, without limitation.

When a component of the gyratory crusher <NUM> is worn (including, but not limited to, an eccentric liner <NUM>, mantle <NUM>, dust seal <NUM>, lower mainshaft <NUM>, concave <NUM>, or other component), a spider <NUM> may be removed from the gyratory crusher <NUM> and the mainshaft assembly <NUM> removed by lifting the mainshaft assembly <NUM> upwardly from the gyratory crusher <NUM> via an overhead crane. The mainshaft assembly <NUM> may need to be removed completely from the gyratory crusher <NUM> to replace a mantle <NUM> thereon, or, to gain access to replace portions of concave <NUM> which have worn.

Turning now to <FIG> and <FIG>, a gyratory crusher <NUM> according to embodiments comprises a mainshaft assembly <NUM>. The mainshaft assembly <NUM> comprises a mantle <NUM> (e.g., outer crushing surface liner), a lower mainshaft <NUM> adjacent its lower distal portion, and a lift hook <NUM> adjacent its upper proximal portion.

The gyratory crusher <NUM> may further comprise a mainframe which may include a lower top shell <NUM>, a bottom shell <NUM>, and a top shell <NUM>, without limitation. Any two or more of the shell portions <NUM>, <NUM>, <NUM> may be made integral with each other, without limitation. A spider <NUM> may span a top opening as shown. A concave <NUM> (e.g., inner crushing surface liner) may protect the inner portions of the mainframe. The mainshaft assembly <NUM> may be received within a liner <NUM> of an eccentric <NUM>. An annular dust bonnet <NUM> may be provided around the mainshaft assembly <NUM>, and an annular dust seal <NUM> may be provided around an outer.

surface of the dust bonnet <NUM>. A counterweight <NUM> may be affixed to an upper portion of eccentric <NUM> and/or eccentric liner <NUM>. The counterweight <NUM> may comprise a non-annular arcuate shape (e.g., a "C" shape), as shown, without limitation.

As exemplified in <FIG>, the gyratory crusher <NUM> may differ from conventional gyratory crushers in that its dust bonnet <NUM> may comprise a number of guide mounts <NUM> provided to an inner sidewall <NUM> of the dust bonnet <NUM>. The guide mounts <NUM> may extend at an angle between the inner sidewall <NUM> and a lower sidewall <NUM> of the dust bonnet <NUM> as shown. The lower sidewall <NUM> may extend radially inwardly (e.g., perpendicularly to the inner sidewall <NUM> when viewed in cross-section). The lower sidewall <NUM> may form a radially-inwardly extending shelf, lip, or flange, without limitation.

As depicted in <FIG>, an upper peripheral region of the dust bonnet <NUM> may comprise an upper radially-outer chamfer <NUM> which is configured with an angle which works in harmony with a lower radially-inner chamfer <NUM> of dust seal <NUM> provided within the mainshaft assembly <NUM> and held in place by dust seal cover <NUM>. As the mainshaft assembly <NUM> is lowered into place during mainshaft assembly <NUM> re-installation, the upper radially-outer chamfer <NUM> on the dust bonnet <NUM> engages the lower radially-inner chamfer <NUM> of the dust seal <NUM>. The surfaces of the two chamfers <NUM>, <NUM> engage and act as an inclined ramp surface to give a mechanical advantage in widening/radially-expanding annular dust seal <NUM> and/or guide inner surfaces of the dust seal <NUM> around outer peripheral surface <NUM> of dust bonnet <NUM>. <FIG> shows a mainshaft assembly <NUM> position where the dust seal <NUM> has slid past the upper radially-outer chamfer <NUM> and past a majority of the outer peripheral surface <NUM> of the dust bonnet <NUM>.

The guide mounts <NUM> may be configured with an integrally-formed guide surface or, as shown, may be configured to receive one or more separable guides <NUM>. Each guide <NUM> may comprise, for instance, a replaceable wear surface or liner, without limitation. Guides <NUM> may comprise a bearing material such as bronze or a polymer, without limitation.

In the particular exemplary, non-limiting embodiment shown (most clear from <FIG>), guide mounts <NUM> may each be provided with an inclined base surface <NUM>, such as a ramp structure. The inclined base surface <NUM> may, itself, be a guide surface configured for and intended for sliding against an end plate <NUM> or other portion of mainshaft assembly <NUM> (e.g., an outer diameter or peripheral surface of lower mainshaft <NUM>), without limitation. However, as shown, a replaceable/separable guide <NUM> may be affixed to the inclined base surface <NUM> using one or more fasteners <NUM> (e.g., machine screw, bolt), without limitation. It should be understood that permanent or semi-permanent attachment methods (e.g., brazing, welding, adhering) may be used to affix a guide <NUM> to a guide mount <NUM>, without limitation.

To better support a guide <NUM> from lateral forces and/or side loading (e.g., tangential forces within dust bonnet <NUM>) caused during mainshaft assembly <NUM> insertion, one or more side rails <NUM> protruding from inclined base surface <NUM> may be provided on either or both sides of the guide(s) <NUM> as shown. The side rails <NUM> may project radially inwardly from guide mount <NUM> with respect to the dust bonnet <NUM>, and may extend along guide mount <NUM> at an angle between inner <NUM> and lower <NUM> sidewalls. The side rails <NUM> may extend generally perpendicularly from the inclined base surface <NUM>, without limitation.

Each guide <NUM> may comprise one or more apertures <NUM> (e.g., one or more countersunk recesses) for receiving one or more respective fasteners <NUM> as depicted. An aperture <NUM> described herein may be sized and shaped to complimentarily receive a head of a fastener <NUM> as shown, and/or configured such that the fastener <NUM> does not protrude past an outer guide surface of a guide <NUM>, without limitation.

One or more side apertures <NUM> may be provided transversely to a separable or integral guide <NUM> as shown, and these may serve to receive one or more respective side pins <NUM> for temporarily or permanently securing a guide <NUM> to a guide mount <NUM>, without limitation. Side pins <NUM> may extend entirely through guide mount <NUM>, or partially into each guide <NUM> as shown. Side pins <NUM> may comprise roll pins, rollers, screws or other type of fastener which are pressed screwed into, or otherwise received through a side rail <NUM> and guide <NUM>, without limitation. Guide mounts <NUM> may also comprise one or more side apertures <NUM> to receive the side pins <NUM> as shown, without limitation. As shown in the particular embodiment, side pins <NUM> may intersect apertures <NUM> so as to serve as set screws against fasteners <NUM>, or other locking features without limitation. As shown, side pins <NUM> may extend through side rails <NUM>.

One or more mounting holes <NUM> may be provided to each guide mount <NUM> for receiving fasteners <NUM> (e.g., a fastener <NUM> extending through guide <NUM> and received within aperture <NUM>).

Turning now to <FIG>, a distal portion of the mainshaft assembly <NUM> may be configured to rest on a thrust bearing <NUM>, and the lower mainshaft <NUM> may be configured to be received within the lined eccentric <NUM>.

As exemplified in <FIG>, the gyratory crusher <NUM> may differ from conventional gyratory crushers in that a lower mainshaft <NUM> of the mainshaft assembly <NUM> may comprise a specially-configured bottom plate <NUM>. In some embodiments, the lower mainshaft <NUM> may comprise a recess <NUM> (<FIG>) within its distal end as shown. The recess <NUM> may be defined, for example, by a bottom surface <NUM> surrounded by a lower annular projection <NUM>, without limitation. The lower annular projection <NUM> may be continuous as shown; however, it may comprise interruptions (e.g., so as to be castellated or partially castellated, undulating, scalloped, or the like), without limitation. The lower annular projection <NUM> may be configured to engage with and/or abut an upper annular lip <NUM> adjacent an upper side of the end plate <NUM> as suggested in <FIG>. Surfaces of the lower annular projection <NUM> may snugly abut complementary surfaces and/or geometric features of the lower annular projection <NUM>, without limitation. The upper annular lip <NUM> of the end plate <NUM> may be defined around or surround an upper projection <NUM> which is configured to extend into recess <NUM> of the lower mainshaft <NUM>, without limitation. The upper projection <NUM> may protrude upwardly from the upper annular lip <NUM> and may be arranged centrally and/or concentrically with respect thereto as shown.

A lower side of the bottom plate <NUM> may comprise a number of radial oil grooves <NUM> and/or one or more annular oil grooves <NUM> may be provided on its bottom surface, without limitation. The grooves <NUM>, <NUM>, may assist with the holding and channeling of oil between the end plate <NUM> and thrust bearing <NUM> thereby facilitating lubrication. The radial oil grooves <NUM> may be interrupted along a radial line as shown, so as to form a plurality of staggered arcuate block projections <NUM>. The staggered arcuate block projections <NUM> may form a circular tile mosaic pattern as illustrated. The radial <NUM> and annular <NUM> oil grooves may be interconnected such that they collectively form a tortuous path for oil to move, thereby improving upon the "rose" pattern shown in <FIG>.

A central pocket <NUM> may be provided to the lower side of the end plate <NUM> for receiving a fastener <NUM> for securing the end plate <NUM> to the lower mainshaft <NUM>. However, it is conceived that a pattern of spaced pockets (centrally-disposed or not) may be provided and arranged within end plate <NUM> in order to provide means for securing the end plate <NUM> to the lower mainshaft <NUM>.

As suggested in the particular non-limiting embodiment shown, the fastener <NUM> may comprise a bolt or threaded pin, without limitation. The fastener <NUM> may, as shown in <FIG>, be received through an opening or mounting hole <NUM> in the end plate <NUM> and threaded into, welded into, or otherwise mounted within a bore <NUM> of the lower mainshaft <NUM> without limitation. The bore <NUM> may be centrally located within recess defined by bottom surface <NUM> and lower annular projection <NUM>. The fastener <NUM> may comprise a projection integral with the lower mainshaft <NUM> and machined into the lower mainshaft <NUM>, without limitation. A fastening nut or bolt head <NUM> may be situated within the central pocket <NUM> of the end plate <NUM> so as to be clear from impingement with the thrust bearing <NUM> supporting the lower side of end plate <NUM>.

Another feature which may be employed to the end plate <NUM> is a lower alignment chamfer <NUM> (e.g., a frustoconical taper or lead-in surface). The lower alignment chamfer <NUM> may match the taper angle of an upper alignment chamfer <NUM> of the lower annular projection <NUM> as shown. A lower annular edge of the upper alignment chamfer <NUM> may abut or meet with an upper annular edge of the upper annular lip <NUM>, as shown. Surfaces of the upper alignment chamfer <NUM> and lower alignment chamfer <NUM> may be flush with one another, collectively continuous, or generally follow the same outer chamfer taper angle - thereby creating a smooth homogeneous transition between lower mainshaft <NUM> and end plate <NUM>.

To prevent relative movement between end plate <NUM> and lower mainshaft <NUM>, mating surfaces between upper annular lip <NUM> and lower annular projection <NUM> may be interlocking (e.g., undulating, scalloped, undulating), without limitation. Moreover, the outer surface of upper projection <NUM> and inner surface of lower annular projection <NUM> can be complimentary splined surfaces, without limitation. However, as shown, in some embodiments, rotation of end plate <NUM> with respect to lower mainshaft <NUM> may be discouraged or prevented by providing one or more alignment pins <NUM> to bottom surface <NUM> such that they protrude into respective alignment holes <NUM>. In this regard, upper projection <NUM> can be prevented from spinning within lower annular projection <NUM> during operation, which could cause loosening of fasteners <NUM>, <NUM> attaching the end plate <NUM> to the lower mainshaft <NUM>.

<FIG> show a conventional end plate (according to the prior art) of which end plate <NUM> aims to improve upon. As can be seen from these figures, a conventional end plate comprises a cylindrical body provided with a rose pattern of oil grooves at its lower surface. The outer peripheral cylindrical surface is radially-inwardly inset from other surfaces of a distal end of a lower mainshaft. Clearly, this traditional design lacks the novel and useful features described above for end plates <NUM> according to embodiments of the invention.

Turning now to <FIG>, another novel feature of the gyratory crusher <NUM> is the provision of an alignment chamfer <NUM> to a counterweight <NUM> which is intended for attaching to an upper portion of an eccentric <NUM> and/or liner <NUM> thereof. The counterweight may comprise a non-annular arcuate shape (e.g., a "C" shape), as shown, without limitation.

The alignment chamfer <NUM> may, as shown, be provided to an inner concave portion of the counterweight, such that the counterweight <NUM> is generally narrower in width adjacent an upper part of the counterweight <NUM> and generally wider in width adjacent a lower part of the counterweight <NUM>.

In some embodiments, a number of projections <NUM> may be provided to a lower face of the counterweight <NUM> (<FIG>). These projections <NUM> may serve as centering features, without limitation. As shown in <FIG>, the projections <NUM> may rest in a gap shelf between eccentric <NUM> and inner liner <NUM>. Mounting holes <NUM> (which may be countersunk as shown) may be provided through counterweight <NUM>. In some embodiments, such as the one shown, mounting holes <NUM> may extend into, disrupt, or intersect the alignment chamfer <NUM>. Mounting holes <NUM> may also extend through projections <NUM>, for example, to increase length of engagement between the fasteners and the mounting holes <NUM>. The mounting holes <NUM> may enable fasteners (not shown) to pass through the counterweight and into a portion of the eccentric <NUM> and/or liner <NUM> to secure the counterweight <NUM> thereto.

Turning now to <FIG>, as the mainshaft assembly <NUM> is lowered into the gyratory crusher <NUM> during reintroduction or reassembly, guides <NUM> help "rough center" the lower mainshaft <NUM> into alignment with the oil seal(s) <NUM> and/or eccentric <NUM>. The smooth lead-in taper collectively formed by the flush lower alignment chamfers <NUM>, <NUM> presents itself to oil seal(s) <NUM> to more "finely align" the lower mainshaft <NUM> with the oil seal(s) <NUM> and/or eccentric <NUM>. As the mainshaft assembly <NUM> is further lowered into the gyratory crusher <NUM>, oil seal(s) <NUM> may be guided around outer peripheral surfaces (i.e., the outer diameter of) lower mainshaft <NUM>.

Upon even further lowering of mainshaft assembly <NUM>, the smooth lead-in taper collectively formed by the flush lower alignment chamfers <NUM>, <NUM> subsequently presents itself to the alignment chamfer <NUM> of counterweight <NUM>. One or both of lower alignment chamfers <NUM>, <NUM> may ride against surfaces of alignment chamfer <NUM> to supplementally finish guiding the lower mainshaft <NUM> into the eccentric <NUM> (e.g., into a liner <NUM> disposed therein), without limitation.

Synergistic combinations of features <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, disclosed herein may contribute to a greater self-aligning/self-centering effect.

For example, it is envisaged that in some embodiments, an eccentric liner <NUM> may be entirely optional. The eccentric liner <NUM> may be omitted from the eccentric <NUM> (wherein the bore <NUM> and/or inner diameter <NUM> may be formed directly through the body of eccentric <NUM>). Or, an eccentric liner <NUM> may be provided as an integral surface portion of eccentric <NUM>. The eccentric liner <NUM> and eccentric <NUM> may be, in some embodiments, provided as a monolithic unitary structure and may be inseparable from each other, without limitation. The eccentric liner <NUM> and eccentric may also be provided as separable parts which have a clearance fit or press fit between them. Accordingly, where it is used herein and in the claims, the terms "bore <NUM>" and "inside diameter" <NUM> may relate to an opening through an eccentric <NUM> or its liner <NUM> - whichever is smaller in diameter, configured to receive the lower mainshaft <NUM>, and/or which comprises the bearing surfaces designed to abut, envelope, or constrain lateral movement of the outer peripheral diametrical surface of lower mainshaft <NUM>, without limitation.

As yet another example, it should be further understood that where it is used herein and in the claims, the term "guide <NUM>" may refer to a separable guide structure that is removably affixed or mounted to a separate guide mount <NUM> as depicted in the figures; or, it may broadly refer to or encompass any structure connected to, integral with, attached to, or extending from the inner surface <NUM> of the dust bonnet <NUM> which is adequately configured to help concentrically align a lower mainshaft <NUM> of the mainshaft assembly <NUM> with one or more oil seals <NUM> and/or the inside diameter <NUM> of bore <NUM> of the eccentric <NUM> or its optional liner <NUM>. The term "guide <NUM>" may also refer to or encompass any structure connected to, integral with, attached to, or extending from the inner surface <NUM> of the dust bonnet <NUM> which is adequately configured to help guide the lower mainshaft <NUM> into an oil seal(s) <NUM>, eccentric <NUM>, eccentric liner <NUM>, bore <NUM>, and/or inside diameter <NUM> when the mainshaft assembly <NUM> is lowered into the gyratory crusher <NUM>, without limitation.

Claim 1:
An annular dust bonnet (<NUM>) for a gyratory crusher (<NUM>), the dust bonnet (<NUM>) being configured to facilitate alignment between a mainshaft assembly (<NUM>) and a bore (<NUM>) of an eccentric (<NUM>) or eccentric liner (<NUM>) upon introduction of the mainshaft assembly (<NUM>) into the gyratory crusher (<NUM>) by lowering the mainshaft assembly (<NUM>) from above the gyratory crusher (<NUM>) into the gyratory crusher (<NUM>); the dust bonnet (<NUM>) comprising:
an inner sidewall (<NUM>) configured for receiving a lower mainshaft (<NUM>) of the mainshaft assembly (<NUM>) therethrough; and
an outer sidewall (<NUM>) configured for engaging an annular dust seal (<NUM>) provided within the mainshaft assembly (<NUM>);
the dust bonnet (<NUM>) being CHARACTERISED IN THAT it further comprises a plurality of guides (<NUM>) arranged radially-inwardly with respect to the inner sidewall (<NUM>), each of the plurality of guides (<NUM>) having a guiding surface (<NUM>') configured to contact the mainshaft assembly (<NUM>); the guiding surface (<NUM>') forming an angle (<NUM>) with respect to the inner sidewall (<NUM>) such that a lower portion of each guiding surface (<NUM>') is positioned further radially-inwardly with respect to the inner sidewall (<NUM>) than a respective upper portion of each guiding surface (<NUM>'); the guides (<NUM>) collectively being arranged and configured to bias the lower mainshaft (<NUM>) into concentric alignment with the bore (<NUM>) when the mainshaft assembly (<NUM>) is lowered into the gyratory crusher (<NUM>); the dust bonnet (<NUM>) further comprising a plurality of guide mounts (<NUM>) provided to the inner sidewall (<NUM>), each of the guide mounts (<NUM>) being configured to support and supporting a respective one of said guides (<NUM>) in at least a radial direction wherein the dust bonnet comprises a lower sidewall (<NUM>) extending radially inwardly with respect to the inner sidewall (<NUM>); the lower sidewall (<NUM>) forming an inner annular lip or inner annular flange proximate a lower portion of the dust bonnet (<NUM>); and wherein the guide mounts (<NUM>) are generally configured as triangular prisms or gussets.