Patent Description:
Quarried material is often processed, by means of a crushing plant, for the production of aggregate, for example. There are various known forms of crushing plant for the comminution of rock material and the like, one of which is referred to as a cone crusher.

One known type of cone crusher <NUM> is shown in <FIG>. The cone crusher <NUM> is of the type commonly referred to as a "spider crusher" and includes a top shell <NUM> and a bottom shell <NUM>, which are bolted together along a split line <NUM> located approximately halfway up the crusher <NUM>.

A crusher head <NUM> is supported by a shaft <NUM>, which is supported at its upper end by a spider assembly <NUM> and at its lower end by a hydraulically actuated piston assembly <NUM>. The shaft <NUM> is slideably supported such that actuation of the piston assembly <NUM> raises and/or lowers the shaft <NUM> with respect to the top shell <NUM>. In this way the spacing between crush surfaces <NUM>, <NUM> can be adjusted. In addition, the position of the crusher head <NUM> can be adjusted to compensate for wear of the crush surfaces <NUM>, <NUM>.

There are a number of disadvantages with such known spider crushers. For example, the design is very tall which makes it difficult to install in some applications, particularly on mobile equipment.

Additionally, in order to change the wear parts, the top shell and bottom shell must be detached from each other. This can be difficult and time consuming due to the number of large bolts holding the two halves together and the difficulty in separating the two sections. Further, the wear parts can suffer from uneven wear if the feed is distributed unevenly around the chamber. This can cause significant problems.

The present invention seeks to overcome or at least mitigate / alleviate one or more problems associated with the prior art.

<CIT> discloses a gyratory crusher and slide bearing lining.

<CIT> discloses a gyratory crusher bearing.

In a first embodiment, a cone crusher is provided comprising a frame having a top shell assembly and a bottom shell assembly, and a crusher main shaft slidably supported by the frame; the top shell assembly comprising a spider assembly having a central hub for receiving a top end of the main shaft of the crusher; the bottom shell assembly comprising a hydraulically operated piston assembly configured to raise and/or lower the main shaft with respect to the frame; the top shell assembly further comprising a first crush surface; the crusher further comprising a crusher head assembly supported by the main shaft, the crusher head assembly comprising a second crush surface, wherein the first and second crush surfaces define therebetween a crushing chamber and an opening through which material leaves the crushing chamber when the crusher is in use; wherein the crusher further comprises an adjustment arrangement configured to adjust the position of the first crush surface.

In this way, the position of the first crush surface (e.g. a concave ring) with respect to the second crush surface (e.g. a mantle) can be adjusted via the adjustment arrangement. The relative position of the first and second crush surfaces can also be adjusted via operation of the piston assembly. Accordingly, two means of adjusting the relative position of the first and second crush surfaces are provided.

In this way, greater control over the relative spacing between the first and second crush surfaces is provided. In exemplary embodiments, this may be advantageous in maintaining even wear of the crush surfaces and/or adjusting the spacing between the surfaces to set the closed side setting (CSS), corresponding to the size of material which can leave the crush chamber via the spacing between the crush surfaces.

Optionally, the crusher head assembly is configured to gyrate about an axis, and the adjustment arrangement is configured to adjust the angular position of the first crush surface with respect to the axis.

In this way, the first crush surface can be rotated with respect to the second crush surface. This enables more even wear of the first crush surface to be achieved. Uneven wear of the first crush surface can effectively create variation in the closed side setting (CSS) around the crushing chamber. This can lead to bearing failures, can limit the minimum achievable CSS, and/or create more variation in the size of the crushed product produced by the crusher. Generating more even wear of the first crush surface mitigates or eliminates some or all of these problems, in addition to increasing the lifespan of the first crush surface. Accordingly, where the first crush surface comprises a replaceable concave ring, the concave ring will need to be replaced less often, reducing cost and downtime.

Optionally, the crusher head assembly is configured to gyrate about the or an axis, and the adjustment arrangement is configured to adjust the axial position of the first crush surface with respect to the axis.

In other words, the first and second crush surfaces can be brought towards or away from each other via the adjustment arrangement. An advantage of this is that the spacing between the crush surfaces can be set to a desired spacing, at least in part, via the adjustment arrangement. Accordingly, a desired closed side setting (CSS) can be specified, at least in part, via the adjustment arrangement.

The piston assembly is configured to raise and lower the main shaft, on which the crusher head assembly is carried. In this way, the crusher head assembly, and hence the second crush surface can be moved towards and away from the first crush surface, thereby adjusting the spacing between the surfaces, and hence the closed side setting (CSS).

It will therefore be apparent that two means for adjusting the spacing between the crush surfaces are provided: the adjustment arrangement and the piston assembly. These may be used independently or in combination.

By providing two means for adjusting the spacing between the crush surfaces, a piston assembly configured to move the main shaft through a reduced length can be provided, as compared to crusher assemblies wherein a piston assembly is the only means of spacing adjustment. Accordingly, cone crushers disclosed herein may be shorter in height as compared to crusher assemblies in which a piston assembly is the only means of spacing adjustment.

Furthermore, since cone crushers disclosed herein are spider crushers having a central hub for receiving a top end of the main shaft of the crusher, the clearance required between the main shaft and the central hub and/or the clearance required between the crusher head assembly and the central hub can be reduced. Thereby providing twice the reduction in height for a given reduction in travel distance of the main shaft.

Further, since the piston assembly is required to move the main shaft through a reduced distance, a more compact piston assembly can be provided, thereby reducing the overall height of the crusher.

Consequently a more compact spider cone crusher is provided as compared to those known from the prior art.

Optionally, the adjustment arrangement is configured to adjust the axial position of the first crush surface with respect to the axis by up to <NUM>, for example by up to <NUM>, for example by up to <NUM>, e.g. by up to <NUM>.

For example, where the second crush surface is a mantle, for a cone crusher having a mantle diameter of <NUM> (i.e. the largest diameter), the adjustment arrangement may be configured to adjust the axial position of the first crush surface with respect to the axis by up to <NUM>. It will be appreciated that, in some embodiments, an adjustment arrangement configured to permit a larger or smaller amount of adjustment may be provided.

It will also be appreciated that the adjustment arrangement provided may be configured to adjust the axial position of the first crush surface with respect to the axis by an amount appropriate for the size and/or proportions of the cone crusher.

Optionally, the adjustment arrangement comprises a screw thread coupling between the top shell assembly and the bottom shell assembly.

In this way, a simple means for adjusting both the axial and angular position of the first crush surface with respect to the axis is provided.

Optionally, the screw thread coupling comprises an inner thread arranged on an outer surface of the top shell assembly and an outer thread arranged on an inner surface of the bottom shell assembly.

In some embodiments, the screw thread coupling comprises an inner thread arranged on an outer surface of the bottom shell assembly and an outer thread arrangement arrange on an inner surface of the top shell assembly.

Optionally, the hydraulically operated piston assembly comprises a relief device for releasing the hydraulic pressure in the piston assembly in the event that the pressure exceeds a predetermined threshold.

If an uncrushable object enters the crushing chamber, substantial forces may be generated in the hydraulically operated piston assembly as the crusher head assembly acts to complete its gyratory motion against the uncrushable object. The generation of these forces can cause damage to the crusher. In some cases, this damage can render the crusher inoperative until it is repaired, therefore affecting productivity.

When the forces generated by the uncrushable object in the crushing chamber exceed a predetermined amount, the relief device is actuated. Such actuation releases the hydraulic pressure in the piston assembly, which prevents or limits damage to the crusher.

In this way, the relief device acts to protect the crusher against damage resulting from an uncrushable object entering the crushing chamber.

In exemplary embodiments, the relief device is configured to actuate when a predetermined force of between <NUM> and <NUM> bar is reached, for example between <NUM> and <NUM> bar, for example between <NUM> and <NUM> bar, for example between <NUM> and <NUM> bar.

Optionally, the hydraulically operated piston assembly is arranged to support a lower end of the main shaft and the relief device is configured to release the hydraulic support of from the piston assembly in the event that the pressure exceeds a predetermined threshold.

Optionally, the piston assembly comprises a piston moveable in a cylinder, wherein the piston is configured to raise and/or lower the main shaft with respect to the frame. Optionally, the cylinder has a length of less than <NUM>, for example less than <NUM>, for example in the range of <NUM> to <NUM>, e.g. <NUM>.

In cone crushers disclosed herein, since the amount of axial movement of the main shaft is reduced, a cylinder of reduced length as compared to an equivalent known spider crusher can be used. It will be appreciated that the cylinder dimensions may be appropriate for the size and/or proportions of the cone crusher.

Optionally, the maximum vertical distance through which the main shaft can be raised and/or lowered is less than <NUM>, for example less than <NUM>.

In other words, the piston assembly is configured such that the piston can be moved through less than <NUM>, for example less than <NUM>. In cone crushers disclosed herein, since two means of adjusting the relative position of the first and second crush surfaces are provided, the vertical distance through which the main shaft can be raised and/or lowered can be less than that of an equivalent known spider crusher.

Optionally, the maximum vertical distance is in the range of <NUM> to <NUM>, for example, <NUM> to <NUM>, e.g. <NUM>.

Optionally, when the main shaft is in a fully retracted position (i.e. away from the spider assembly), a clearance is defined between a top end of the main shaft and an underside of the central hub directly above the top end of the main shaft when the crusher is in use. Optionally, the clearance is less than <NUM>, for example <NUM>, for example in the range of <NUM> to <NUM>, for example, <NUM> to <NUM>, e.g. <NUM>.

It will be appreciated that the clearance required will be the same as the distance through which the main shaft can be raised or lowered. Consequently, since cone crushers disclosed herein can be configured such that the distance through which the main shaft can be raised or lower is reduced, as compared to equivalent known spider crushers, the clearance required is correspondingly reduced.

Accordingly, the reduction in overall height of the cone crushers disclosed herein can be twice the reduction in the distance through which the main shaft can travel. This provides a more compact cone crusher than equivalent known spider crushers.

Optionally, when the main shaft is in a fully retracted position (i.e. away from the spider assembly), a clearance is defined between an uppermost surface of the crusher head and a lower surface of the central hub directly above the uppermost surface of the crusher head. Optionally, the clearance is less than <NUM>, for example in the range of <NUM> to <NUM>, for example, <NUM> to <NUM>, e.g. <NUM>.

Optionally, the second crush surface comprises a mantle having a diameter at its widest point in the range of <NUM> to <NUM>, e.g. <NUM>.

In exemplary embodiments, the mantle diameter may be in the range of <NUM> to <NUM>, for example <NUM> to <NUM>.

Optionally, the second crush surface comprises a mantle and the ratio of the mantle diameter : overall height of the crusher is <NUM> to less than <NUM>, for example, in the range of <NUM>:<NUM> to <NUM>:<NUM>, for example <NUM>:<NUM>.

As used herein, the term "overall height of the crusher" is understood to mean the distance from the top of the spider assembly (corresponding to a clearance under a feeder when in use) to the lowest part of the piston assembly (corresponding to a clearance above a discharge conveyor when in use).

Optionally, the overall height of the crusher is in the range <NUM> to <NUM>, for example <NUM> to <NUM>, for example <NUM> to <NUM>, e.g. <NUM>.

As previously described, cone crushers disclosed herein may have a reduced height as compared to equivalent known spider crushers.

Optionally, the cone crusher further comprises a locking mechanism which is configured to prevent or inhibit movement of the concave ring.

In this way, once the position of the first crush surface has been adjusted to a desired position, the first crush surface can be locked in this position via the locking mechanism.

Optionally, the adjustment arrangement comprises a screw thread coupling between the top shell assembly and the bottom shell assembly, and the locking mechanism comprises a threaded ring configured to be threaded onto the screw thread coupling such that the threaded ring can be tightened to exert a force against the top shell assembly or bottom shell assembly.

In this way, relative rotation and the top and bottom shell assemblies and/or tilting of the top shell assembly when crushing can be inhibited.

Optionally, the bottom shell assembly comprises a central hub for supporting the or a lower end of the main shaft of the crusher, and an eccentric is mounted on the lower end of the main shaft and configured such that, in use, the eccentric rotates eccentrically about the or an axis causing gyration of the crusher head. Optionally, bearings are provided between the eccentric and the central hub.

In exemplary embodiments, the bearings comprise an uppermost bearing and a lowermost bearing. In cone crushers disclosed herein, since two means of adjusting the relative position of the first and second crush surfaces are provided, the vertical distance through which the main shaft can be raised and/or lowered can be reduced as compared to an equivalent known spider crusher. Consequently, the spacing between the uppermost and lowermost bearings may be reduced as compared to equivalent known spider crushers. Consequently a more compact and/or simplified bearing assembly can be provided.

Optionally, the crusher head assembly is configured to gyrate about the or an axis, and the adjustment arrangement is configured to adjust the angular position of the first crush surface with respect to the axis by adjusting the angular position of the top shell assembly.

Optionally, the crusher comprises an alignment arrangement configured to restrict an angular position of the top shell assembly to one of one or more predetermined angular positions, when the crusher is in use.

In this way, the angular position of the spider assembly can be controlled.

Optionally, the alignment arrangement comprises a sensor for sensing the angular position of the top shell assembly.

Optionally, the one or more predetermined angular positions are determined based on the relative positions of the spider assembly and a feed source.

In this way, the position of the top shell can be adjusted such that the feed source is aligned with an opening in the spider assembly (i.e. between spider arms of the spider assembly). Accordingly, introduction of material into the crusher is optimised.

Embodiments of the disclosure will now be described with reference to the accompanying drawings, in which:.

An embodiment of a cone crusher <NUM> disclosed herein is illustrated in <FIG>. The crusher <NUM> includes frame <NUM> having a top shell assembly <NUM> and a bottom shell assembly <NUM>. The crusher <NUM> comprises a main shaft <NUM> which is slideably supported by the frame <NUM>.

The top shell assembly <NUM> comprises a top shell frame <NUM> having an outer surface 106a and an inner surface 106b. Similarly, the bottom shell assembly <NUM> comprises a bottom shell frame <NUM> having an outer surface 108a and an inner surface 108b.

The top shell assembly <NUM> includes a spider assembly <NUM> having a central hub <NUM> for receiving a top end of the main shaft <NUM>. The bottom shell assembly <NUM> is configured to support a lower end of the main shaft <NUM> and includes a hydraulically actuated piston assembly <NUM> configured to raise and/or lower the main shaft <NUM> with respect to the frame <NUM>.

In the illustrated embodiment shown in <FIG>, the top shell frame <NUM> and the spider assembly <NUM> are integrally formed. In some embodiments, the top shell frame and the spider assembly are separate components.

The crusher <NUM> includes a first crush surface <NUM> which is provided by the top shell assembly <NUM>. In the illustrated embodiment, the first crush surface <NUM> is carried by the inner surface 106b of the top shell frame <NUM>. In use, material fed into the crusher <NUM> is crushed against the first crush surface <NUM>. In the illustrated embodiment, the first crush surface <NUM> comprises a concave ring. The concave ring <NUM> is a wearable component and can be removed and replaced when it is worn out.

The crusher <NUM> also includes a crusher head assembly <NUM> carried by the main shaft <NUM>. The crusher head assembly <NUM> comprises a crusher head <NUM> and a second crush surface <NUM> against which material fed into the crusher <NUM> is crushed. In the illustrated embodiment, the second crush surface <NUM> comprises a mantle carried by the crusher head <NUM>, wherein the mantle <NUM> is a wearable component that can be removed and replaced when worn.

A crushing chamber <NUM> is defined between the crush surfaces, i.e. between the concave ring <NUM> and the mantle <NUM>. The crush surfaces <NUM>, <NUM> further define an opening <NUM> through which material leaves the crushing chamber <NUM> when the crusher <NUM> is in use.

The crusher <NUM> includes an adjustment arrangement <NUM> configured to adjust the position of the first crush surface <NUM> of the top shell assembly <NUM> (i.e. the concave ring <NUM>) with respect to the crusher head assembly <NUM>, and hence with respect to the second crush surface <NUM>.

As will be described in further detail below, the crusher head <NUM> is arranged to gyrate about an axis X, e.g. a longitudinal axis of the crusher <NUM>. The adjustment arrangement <NUM> is configured to adjust the angular position of the concave ring <NUM> with respect to the axis X. The adjustment arrangement <NUM> is also configured to adjust the axial position of the concave ring <NUM> with respect to the axis X.

In the illustrated embodiment, the adjustment arrangement <NUM> comprises a screw thread coupling between the top shell assembly <NUM> and the bottom shell assembly <NUM>. An inner thread 128a is arranged on the outer surface 106a of the top shell frame <NUM> and an outer thread 128b is arranged on the inner surface 108b of the bottom shell frame <NUM>. In this way, unscrewing the top shell assembly <NUM> from the bottom shell assembly <NUM> enables the axial and angular position of the concave ring <NUM> to be adjusted.

As previously described, the bottom shell assembly <NUM> includes a hydraulically actuated piston assembly <NUM> configured to raise and/or lower the main shaft <NUM> with respect to the frame <NUM>. The piston assembly <NUM> includes a piston <NUM> which is moveable in a cylinder <NUM>. The lower end of the main shaft <NUM> is positioned above the piston <NUM>, such that actuation of the piston <NUM> results in raising/lowering of the main shaft <NUM>.

The hydraulically actuated piston assembly <NUM> also includes a relief device (not shown) for releasing the hydraulic pressure in the piston assembly <NUM> in the event that the pressure exceeds a predetermined threshold. In this way, the piston assembly <NUM> is configured to release the hydraulic support provided to the main shaft <NUM> when the pressure exceeds the predetermined threshold.

In the illustrated embodiment, the crusher includes a locking mechanism <NUM> configured to prevent or inhibit movement of the concave ring <NUM> with respect to the bottom shell assembly <NUM>, e.g. by preventing or inhibiting movement of the top shell frame <NUM> with respect to the bottom shell assembly <NUM>. In this way, once the desired position of the concave ring <NUM> has been set, further movement of the concave ring <NUM> with respect to the bottom shell assembly <NUM> can be prevented or inhibited.

In the illustrated embodiment, the locking mechanism comprises a locking ring <NUM> having a threaded inner surface 134a, configured to engage with the inner thread 128a of the top shell frame <NUM>. When the top and bottom shell assemblies <NUM>, <NUM> are in the desired relative position, the locking ring <NUM> can be rotated down the inner thread 128a of the top shell frame <NUM> towards and into contact with the bottom shell frame <NUM>. Further rotation of the locking ring <NUM> causes the locking ring <NUM> to exert a force against the bottom shell frame <NUM>, thereby inhibiting rotation between the top and bottom shell assemblies <NUM>, <NUM>. The locking ring <NUM> can be thought of as a locking nut. In some embodiments, the locking ring <NUM> may exert a force on the bottom shell frame (to inhibit relative rotation of the shell assemblies) via an intermediate component, such that the locking ring and the bottom shell frame are not in direct contact.

<FIG> illustrates a top-down view of the locking ring <NUM>. As illustrated in <FIG>, a series of hydraulic cylinders <NUM> are provided for rotating the locking ring <NUM> and tightening the locking ring <NUM> to exert force against the bottom shell frame <NUM>. The hydraulic cylinders <NUM> are not shown on <FIG> for clarity. In alternative embodiments, the locking ring <NUM> can be rotated via a gear drive or any other suitable means.

The locking ring <NUM> also acts to inhibit tilting of the top shell assembly <NUM> when the crusher <NUM> is in use. Since the main shaft <NUM> is supported by the spider assembly <NUM> of the top shell assembly <NUM>, rotation of the crusher head assembly <NUM> can cause forces to be applied to the top shell assembly <NUM> when the crusher <NUM> is in use, which can result in tilting of the top shell assembly <NUM>. The locking ring <NUM> acts to inhibit such tilting.

In alternative embodiments, the locking mechanism may comprise hydraulic jacks exerting a force which acts to push the upper and lower shell assemblies <NUM>, <NUM> apart (or towards each other) such that the threads 128a,b are forced against each other, inhibiting relative movement of the shells <NUM>, <NUM>. In alternative embodiments, any other suitable locking means can be used.

With reference to <FIG> and <FIG>, the bottom shell assembly <NUM> includes a central hub <NUM> for supporting a lower end of the main shaft <NUM>. An eccentric <NUM> is mounted on the lower end of the main shaft <NUM> and configured such that, in use, the eccentric <NUM> rotates eccentrically about the axis X, thereby causing gyration of the crusher head assembly <NUM> about the axis X. In some embodiments, the axis X is coaxial with a longitudinal axis of the crusher <NUM>.

Bearings 136a, b are provided between the eccentric <NUM> and the central hub <NUM>. These bearings comprise an upper bearing 136a and a lower bearing 136b provided between the eccentric <NUM> and the central hub <NUM> to support the main shaft <NUM> In the illustrated embodiment, bearings 136a,b are roller bearings. In some embodiments, plain bearing (i.e. bushings) are used. In some embodiments, a single bearing is provided.

Additional bearing <NUM> is provided between the main shaft <NUM> and the eccentric <NUM> It will be appreciated by those skilled in the art that the spider assembly <NUM> comprises a series of spider arms <NUM> extending from the central hub <NUM> to an outer diameter of the spider assembly <NUM>. Gaps (not shown) are provided between the spider arms <NUM> and material to be crushed can be fed into the crush chamber <NUM> via one or more of these gaps.

In some embodiments, the crusher <NUM> includes an alignment arrangement 160a, b configured to restrict the angular position of the top shell assembly <NUM>, and hence the spider assembly <NUM>, to one of one or more predetermined angular positions, when the crusher <NUM> is in use.

In some embodiments, the alignment arrangement comprises a sensor 160a for sensing the angular position of the top shell assembly <NUM>. The sensor 160a may be mounted at any suitable location on the bottom shell assembly <NUM>. The sensor 160a may be configured to detect a feature of the top shell assembly <NUM> itself, and from this determine the angular position of the top shell assembly <NUM>. Alternatively, as is shown in <FIG>, the top shell assembly <NUM> may comprise a target 160b configured to be detectable by the sensor 160a. Any suitable sensor and target 160a, b may be used.

The one or more predetermined angular positions may be determined based on the relative positions of the spider assembly <NUM> and a feed source (not shown). For example, the top shell assembly <NUM> may be positioned such that the or each feed source is aligned with one or more of the gaps between the spider arms <NUM> of the spider assembly <NUM>.

In use, material to be crushed is introduced into the crushing chamber <NUM>. As the crusher head assembly <NUM> gyrates about the longitudinal axis X, the mantle <NUM> is caused to gyrate relative to the concave ring <NUM>. In this way, material in the crushing chamber <NUM> is crushed against the mantle <NUM> and the concave ring <NUM> to create smaller pieces of material. When the pieces of material are small enough, they fall through the opening <NUM> between the crush surfaces <NUM>, <NUM>, leaving the crushing chamber <NUM>.

The spacing between the mantle <NUM> and concave ring <NUM> sets the size of material that is produced by the crusher <NUM>. The size of this spacing (i.e. opening <NUM>) is often referred to as the "Closed Side Setting (CSS)".

With reference to <FIG>, the spacing between the mantle <NUM> and the concave ring <NUM> can be adjusted by movement of the piston <NUM> in the cylinder <NUM>. As the piston <NUM> is moved upwards, the main shaft <NUM>, and the crusher head assembly <NUM> carried by the main shaft <NUM>, are consequently also moved upwards due to the action of the piston <NUM>. In this way, the mantle <NUM> and concave ring <NUM> are brought towards each other, thereby reducing the spacing therebetween.

Advantageously, adjustment of the spacing between the mantle <NUM> and the concave ring <NUM> by movement of the piston <NUM> can be carried out during crushing.

As can be seen in <FIG>, the spacing between the mantle <NUM> and the concave ring <NUM> can also be adjusted via the adjustment mechanism <NUM>. By rotating the top shell assembly <NUM> with respect to the bottom shell assembly <NUM>, the top shell assembly <NUM> can be screwed towards or away from the bottom shell assembly <NUM>. In this way, both the axial and angular position of the top shell assembly <NUM> with respect to the crusher head assembly <NUM> can be adjusted.

By making this adjustment, the spacing between the concave ring <NUM>, which is carried by the top shell frame <NUM>, and the mantle <NUM>, which is carried by the crusher head <NUM>, can be adjusted. This adjustment can be used to determine the size of material that is produced by the crusher <NUM> by setting the closed side setting. In some cases, adjustment of the position of the top shell assembly <NUM> with respect to the bottom shell assembly <NUM> can be made to maintain a predetermined closed side setting to compensate for wear of the mantle <NUM> and/or the concave ring <NUM>.

In exemplary embodiments, the concave ring <NUM> is carried by the top shell frame <NUM> such that the concave ring <NUM> is fixed for movement with the top frame assembly <NUM>.

In the illustrated embodiment, the adjustment arrangement <NUM> is configured to adjust the axial position of the concave ring <NUM> with respect to the longitudinal axis X by distance "A", which can be up to <NUM>. In alternative embodiments the adjustment arrangement may be configured to adjust the axial position of the concave ring by up to <NUM>, for example by up to <NUM>, for example by up to <NUM>. It will be appreciated that an adjustment arrangement configured to adjust the axial position of the concave ring by any desired amount can be provided.

Since the spacing between the crush surfaces <NUM>, <NUM> can be set or maintained, at least in part, by positioning the concave ring <NUM> via the adjustment mechanism <NUM>, the extent to which the crusher head assembly <NUM> needs to travel axially can be reduced, whilst still achieving the same degree of control of the spacing between the crush surfaces <NUM>, <NUM>. In other words, since the adjustment arrangement <NUM> is configured to move the concave ring <NUM> towards and away from the mantle <NUM>, the extent to which the mantle <NUM> needs to be moveable towards and away from the concave ring <NUM> can be reduced, whilst still achieving the same degree of control of the closed side setting as for a corresponding crusher of the type shown in <FIG>.

Consequently, the distance through which the piston <NUM> needs to be moveable can be less in crushers disclosed herein as compared to a corresponding crusher of the type shown in <FIG>.

In the illustrated embodiment, the distance through which the piston <NUM> is configured to move is up to <NUM>. By comparison, for an equivalent crusher of the type shown in <FIG>, the piston must be able to move by up to <NUM> in order to achieve the same degree of control of the closed side setting.

Accordingly, the cylinder <NUM> can be of a shorter length as compared to an equivalent crusher of the type shown in <FIG>. In the illustrated embodiment in <FIG>, the cylinder <NUM> has an axial length of <NUM>. By comparison, a corresponding crusher of the type shown in <FIG> has a cylinder having an axial length of <NUM>.

These differences in the piston assembly <NUM> of the embodiment illustrated in <FIG> as compared to the piston assembly <NUM> of a corresponding crusher of the type shown in <FIG> leads to a reduction in the overall height of the crusher of <NUM>. In the illustrated embodiment, this reduction in overall height is achievable for a cone crusher having a mantle diameter of <NUM>. It will be appreciated that different height savings will be achievable for different crusher configurations and sizes. However, for any size of crusher, cone crushers disclosed herein will have a reduced height as compared to an equivalent cone crusher of the type illustrated in <FIG>.

Additionally, since the maximum travel distance of the main shaft <NUM> is reduced, a reduced clearance between an underside <NUM> of the central hub <NUM> of the spider assembly <NUM> and a top end of the main shaft <NUM> is required. This is illustrated by clearance "B" in <FIG>. The clearance required will correspond to the maximum movement of the piston and so for the embodiment of <FIG> will be <NUM>. The corresponding clearance for an equivalent crusher <NUM> of the type shown in <FIG> is <NUM> (i.e. the maximum travel distance of the shaft <NUM>).

Similarly, since the maximum travel distance of the main shaft <NUM> is reduced, a clearance between an uppermost surface of the crusher head <NUM> and a lowermost surface <NUM> of the central hub <NUM> and/or spider assembly <NUM> can also be reduced. In the illustrated embodiment in <FIG>, this is shown as clearance "C" and will also be <NUM>. The corresponding clearance for an equivalent crusher of the type shown in <FIG> is <NUM> (i.e. the maximum travel distance of the shaft <NUM>).

It will therefore be appreciated that a further reduction in the height of the crusher <NUM> is achieved. Accordingly, the total reduction in height of the crusher <NUM> as compared to an equivalent crusher of the type shown in <FIG> is <NUM>.

From the above it will be appreciated that, for a given reduction in the maximum distance through which the piston <NUM>/main shaft <NUM> can travel, a reduction in overall height of the crusher <NUM> equating to twice the reduction in the amount of piston travel is achievable. Further, an additional reduction in height is achievable where there is a reduction in axial length of the cylinder <NUM>.

The overall height of the crusher illustrated in <FIG> is <NUM>, whereas a corresponding crusher of the type shown in <FIG> is <NUM>. Accordingly, an <NUM>% reduction in the total height of the crusher is achievable. In some embodiments, the reduction in the total height of the crusher is in the range <NUM>% to <NUM>%, for example <NUM>% to <NUM>%. It will be appreciated that the illustrations in <FIG> and <FIG> are not to scale.

In the illustrated embodiment in <FIG>, the ratio of the mantle diameter (at its largest diameter) to overall height of the crusher is <NUM>:<NUM>. By way of comparison, an equivalent crusher of the type shown in <FIG> has a mantle diameter to overall machine height ratio of <NUM>:<NUM>. In some embodiments of crushers disclosed herein, this ratio is <NUM> to less than <NUM>, for example, in the range of <NUM>:<NUM> to <NUM>:<NUM>, for example <NUM>:<NUM>. In the illustrated embodiments the mantle diameter is <NUM>.

Again, it will be appreciated that the height savings achievable by crushers disclosed herein depend on the configuration and size of the crusher. However, for any size of crusher, cone crushers disclosed herein can have a reduced height as compared to an equivalent cone crusher of the type illustrated in <FIG>.

Further, adjustment of the position of the concave ring <NUM> via the adjustment arrangement <NUM> has the benefit of enabling adjustment of the angular position of the concave ring <NUM> with respect to the axis X to be achieved. This enables control of the wear of the concave ring <NUM> to avoid uneven wear, and so increases the life span of the concave ring <NUM>.

With reference to <FIG>, since the main shaft <NUM> of the illustrated embodiment is moveable through a reduced distance, the upper and lower bearings 136a, 136b, can be spaced closer together as compared to the corresponding arrangement of <FIG>. This allows for a reduction in component height, which may translate to a reduction in machine height. In embodiments comprising a single bearing between the eccentric <NUM> and the central hub <NUM>, a reduction in the height of the bearing may also be achieved.

Claim 1:
A cone crusher (<NUM>) comprising a frame (<NUM>) having a top shell assembly (<NUM>) and a bottom shell assembly (<NUM>), and a crusher main shaft (<NUM>) slidably supported by the frame (<NUM>); the top shell assembly (<NUM>) comprising a spider assembly (<NUM>) having a central hub (<NUM>) for receiving a top end of the main shaft (<NUM>) of the crusher (<NUM>); the bottom shell assembly (<NUM>) comprising a hydraulically operated piston assembly (<NUM>) configured to raise and/or lower the main shaft (<NUM>) with respect to the frame (<NUM>); the top shell assembly (<NUM>) further comprising a first crush surface (<NUM>); the crusher (<NUM>) further comprising a crusher head assembly (<NUM>) supported by the main shaft (<NUM>), the crusher head assembly (<NUM>) comprising a second crush surface (<NUM>), wherein the first (<NUM>) and second (<NUM>) crush surfaces define therebetween a crushing chamber (<NUM>) and an opening (<NUM>) through which material leaves the crushing chamber (<NUM>) when the crusher (<NUM>) is in use, characterized in that the crusher (<NUM>) further comprises an adjustment arrangement (<NUM>) configured to adjust the position of the first crush surface (<NUM>).