Field of the Invention

The present invention relates to an inner shell for a cone crusher, and a cone crusher comprising the inner shell. The invention also relates to a method of crushing materials such as ore, mineral and rock.

Background to the Invention

Cone (or gyratory) crushers are used for crushing and size reducing hard materials such as ore, mineral and rock. The crusher generally includes a crushing head mounted to a shaft, an inner crushing shell (referred to as an inner shell or mantle) mounted to the crushing head, and a second crushing shell (referred to as an outer shell or concave) is mounted to a frame so that a crushing chamber is defined between the inner shell and outer shell. A drive mechanism operatively connected to the shaft for rotation of the inner shell within the outer shell about an eccentric (gyratory) axis to crush material passed into the crushing chamber. Examples of cone crushers and inner shells for cone crushers are described in EP2818246, EP2774680 and EP1868726.

The inner shell of a some cone crushers have a conical profile and comprise a lower material crushing section (where the material is crushed), an upper material flow restriction section, and a material inlet section disposed between the lower material crushing section and the upper material flow restriction section. A known inner cone for a cone crusher (SANDVIK CH865i crusher - EF Mantle) is illustrated in Figure 1 (comparative). The upper material flow restriction section comprises a plurality of shoulders including a lower shoulder A disposed adjacent to the material inlet section B having a sidewall section C and an arcuate restriction plane section D to slow the entry of material into the material inlet. The inner shell diameter X1 across the sidewall section of the lower material collection shoulder is about 13% less than an inner shell diameter X2 across a top of the material inlet section, and the outer part E of the restriction plane section is arcuate and inclined at an angle of about 15° to the horizontal at its radially outward periphery where it meets the material inlet section.

For a normal given feed size, a cone crusher with this type of inner shell is often intake restricted, meaning that the crusher performance is driven by the size of the material intake section as opposed to the choke zone.

It is an object of the invention to overcome at least one of the above-referenced problems.

Summary of the Invention

The Applicant has discovered that the design of the inner shell above the intake zone is important to the efficiency of the operation of the machine, and that modification of restriction plane section to incorporate a planar (i.e. non-arcuate) outer section with a shallow incline allows the crusher to operate on a lower minimum setting (close side setting), producing a finer product with less recirculation of oversized material. While the gross capacity will be lower, the net production of relevant product fractions will be maintained or even increased.

In a first aspect, the invention provides an inner shell for a cone crusher of the type having an inner shell, an outer shell and a crushing chamber defined between the inner shell and the outer shell, and configured to crush material upon rotation of the inner shell relative to the outer shell, the inner shell having a conical profile and comprising a lower material crushing section, an upper material flow restriction section, and a material inlet section disposed between the lower material crushing section and the upper material flow restriction section, and in which the upper material flow restriction section comprises a lower shoulder section disposed adjacent to the material inlet section having a sidewall section and an arcuate restriction plane section, characterized in that the arcuate restriction plane section of the lower shoulder section has an arcuate inner transition section and an outer section that is inclined radially inwardly at an angle of less than 15° to the horizontal.

The shallow angle of the outer section provides for more efficient restriction of material’ allowing the crusher to operate on a lower minimum setting (close side setting), resulting in a finer product with less recirculation of oversized material. The angle may be varied according to the application and material being crushed and may vary from 0° in some embodiments up to less than 15° in other embodiments.

The outer section of the arcuate restriction plane section is some embodiments is planar (i.e. when viewed in section, it is not arcuate, but is planar (flat). This provides improved restriction of material compared with an arcuate outer section. In any embodiment, the outer section is inclined radially inwardly at an angle of less than 10° or 5° to the horizontal. These embodiments both provide for improved restriction of material in some crushing applications.

In any embodiment, the outer section is inclined radially inwardly at an angle of about 3° to 5° to the horizontal.

In any embodiment, the restriction plane section has a width D3 and the outer section has a width D4, in which D4 is at least 30% or 40% of D3. In any embodiment, D4 may be about 30% to 70% or 30% to 60% of D3. Thus, the width D4 of the planar outer section may be varied according to the application, and a width of at least 30% or 40% has been found to provide excellent flow restriction.

In any embodiment, an inner shell diameter D1 across the sidewall section of the lower shoulder section is at least 15% less than an inner shell diameter D2 across a top of the material inlet section. The difference in D1 and D2 defines the radial width of the lower shoulder. The Applicant has discovered that a difference of at least 15% between D1 and D2 provides a shoulder section providing improved restriction of material flow compared with a difference of less than 15%.

In any embodiment, the inner shell diameter D1 is at least 20% less than an inner shell diameter D2 across a top of the material inlet section. In certain applications, a difference of at least 20% between D1 and D2 has been found to provide improved restriction of material flow compared with a difference of 15%.

In any embodiment, the inner shell diameter D1 is at least 25% less than an inner shell diameter D2 across a top of the material inlet section. In certain applications, a difference of at least 25% between D1 and D2 has been found to provide improved restriction of material flow compared with a difference of 20%. In any embodiment, the inner shell diameter D1 is at least 30% less than an inner shell diameter D2 across a top of the material inlet section. In certain applications, a difference of at least 30% between D1 and D2 has been found to provide improved restriction of material flow compared with a difference of 25%.

In any embodiment, the inner shell diameter D1 is at least 35% less than an inner shell diameter D2 across a top of the material inlet section. In certain applications, a difference of at least 35% between D1 and D2 has been found to provide improved restriction of material flow compared with a difference of 30%.

Generally, and depending on the application, a difference of 15% to 50%, 20% to 40%, or 20% to 35%, between D1 and D2 has been found to provide for improved flow restriction.

In any embodiment, the upper material flow restriction section comprises an upper shoulder section.

In any embodiment, the upper material flow restriction section comprises an upper shoulder section comprising a restriction plane section with a width D5, wherein a ratio of the width D3 of the restriction plane section of the lower shoulder section to the width D5 of the restriction plane section is at least 2:1.

In any embodiment, the ratio of the width D3 of the restriction plane section of the lower shoulder section to the width D5 of the restriction plane section of the upper shoulder section is at least 2.5:1.

In any embodiment, the sidewall section is substantially vertical. In any embodiment, the sidewall section of the lower shoulder section is inclined inwardly, typically at an angle 0’ of about 1 -5° to the vertical. In any embodiment, the sidewall section of the lower shoulder section is inclined inwardly at an angle 0’ of 2-4° or about 3° to the vertical.

In any embodiment, the inner shell has a second diameter D2 across the top of the material inlet section of 500mm to 2000mm, 850mm to 1500mm, or about 900mm to 1100mm.

In any embodiment, the lower shoulder section is fully annular. This embodiment is illustrated in Figure 2.

In any embodiment, the lower shoulder section comprises a plurality of spaced apart steps providing a plurality of interspaced second material crushing sections disposed above the material inlet section. One embodiment of this aspect of the invention is illustrated in Figure 7. The provision of a plurality of interspaced second material crushing sections disposed above the material inlet section has been found to reduce the wear on the material inlet section, and provide a more constant crushing performance over the lifetime of the inner shell or inner shell liner.

Each step generally has a top surface with a planar outer section and an inner arcuate transition section which provides a smooth transition from the outer section to the upright sidewall, side surfaces, and a radially outward facing surface that provides the second material crushing section. The radially outward facing surface is typically radially outwardly inclined so that it is typically substantially co-extensive with an upper region of the material crushing section. In any embodiment, the interspaced material crushing sections are rectangular. This is illustrated in Figure 7. Flowever, it will be appreciated that the spaced-apart steps may have any shape provided that they present second material crushing sections disposed above the material inlet section. Thus, the second material crushing sections may be polygonal, triangular or any other shape. In any embodiment, the spaced apart steps together cover about 25% to 50% of a circumference of the lower shoulder section. This has been found to provide excellent resistance to wear of the material inlet section.

In any embodiment, the shoulder section has 3 to 8 spaced apart steps, and preferably has 6 spaced apart steps. However, the shoulder section may also have 3, 4, 5, 7, 8, or more steps.

In another aspect, the invention provides a bottom shell assembly for a cone crusher comprising an inner shell according to the invention.

In another aspect, the invention provides a cone crusher comprising a bottom shell assembly according to the invention.

In any embodiment, the cone crusher comprises: an inner shell of the invention mounted on a crushing head; an outer shell mounted to a frame; a crushing chamber defined between the inner shell and outer shell; and a drive mechanism operatively connected to the crushing head for rotation of the inner shell within the outer shell, typically about an eccentric axis, to crush material in the crushing chamber.

In another aspect, the invention provides a method of crushing material comprising the steps of: providing a cone crusher according to the invention; actuating the drive mechanism to rotate the inner shell within the outer shell; delivering material to be crushed from above into a gap between the inner shell and outer shell, whereby at least some of the material cascades over the lower shoulder section; and crushing the material between the outer shell and lower material crushing section of the inner shell. In any embodiment, the method is a method of fine crushing of material. In any embodiment, the material is selected from ore, mineral or rock.

Other aspects and preferred embodiments of the invention are defined and described in the other claims set out below.

Brief Description of the Figures

FIG. 1 (comparative) is a sectional view of an inner shell of a known cone crusher (SANDVIK CH865i crusher - EF Mantle).

FIG. 2 is a perspective view of an inner shell according to a first embodiment of the invention.

FIG.3 is a sectional view through the inner shell of Figure 2.

FIG. 4 is a detailed view of the upper material flow restriction section of the inner shell of Figure 3.

FIG. 5 is a further detailed view of the upper material flow restriction section of the inner shell of Figure 3.

FIG. 6 is a further detailed view of the upper material flow restriction section of the inner shell of Figure 3.

FIG. 7 is a perspective view of an inner shell according to a second embodiment of the invention in which the lower shoulder section comprises a plurality of spaced apart steps providing a plurality of interspaced second material crushing sections disposed above the material inlet section.

FIG. 8 is a sectional view of a cone crusher according to the invention including the inner shell of Figures 2 to 6.

Detailed Description of the Invention

All publications, patents, patent applications and other references mentioned herein are hereby incorporated by reference in their entireties for all purposes as if each individual publication, patent or patent application were specifically and individually indicated to be incorporated by reference and the content thereof recited in full.

Where used herein and unless specifically indicated otherwise, the following terms are intended to have the following meanings in addition to any broader (or narrower) meanings the terms might enjoy in the art:

Unless otherwise required by context, the use herein of the singular is to be read to include the plural and vice versa. The term "a" or "an" used in relation to an entity is to be read to refer to one or more of that entity. As such, the terms "a" (or "an"), "one or more," and "at least one" are used interchangeably herein.

As used herein, the term "comprise," or variations thereof such as "comprises" or "comprising," are to be read to indicate the inclusion of any recited integer (e.g. a feature, element, characteristic, property, method/process step or limitation) or group of integers (e.g. features, element, characteristics, properties, method/process steps or limitations) but not the exclusion of any other integer or group of integers. Thus, as used herein the term "comprising" is inclusive or open- ended and does not exclude additional, unrecited integers or method/process steps.

As used herein, the term “cone crusher” or “gyratory crusher” refers to machines designed for crushing and size reducing hard materials such as ore, mineral and rock. The crusher generally includes a crushing head mounted to a shaft, an inner crushing shell (referred to herein as an “inner shell” or “mantle”) mounted to the crushing head, and a second crushing shell (referred to as an outer shell or concave) is mounted to a frame so that a crushing chamber is defined between the inner shell and outer shell. A drive mechanism operatively connected to the shaft for rotation of the inner shell within the outer shell about an eccentric (gyratory) axis to crush material passed into the crushing chamber. Examples of cone crushers and inner shells for cone crushers are described in EP2818246, EP2774680 and EP1868726.

The term “arcuate restriction plane section” refers to a lower part of the lower shoulder section that has an upper sidewall section (that may be inclined inwardly at a shallow angle) and a lower part having an outer (generally planar) section and inner arcuate transition section. The outer planar section is inclined downwardly and radially outwardly at an angle 0 of less than 15° or 10° and in one embodiment, about 3-5°, to the horizontal. The term “to the horizontal” as applied to the angle 0 should be understood to mean that the angle 0 is defined between the outer section and a horizontal line orthogonal to the centre line of the inner shell.

The upper sidewall section may be vertical or inclined radially inwardly at an angle 0’ to the vertical. The term “to the vertical” as applied to the angle 0’ should be understood to mean that the angle 0’ is defined between the upper sidewall section and a vertical line parallel to the centreline.

The term “fully annular” as applied to the lower shoulder section means that the arcuate restriction plane section extends fully around the inner shell, as illustrated in Figure 2 In another embodiment, illustrated in Figure 7 the arcuate restriction plane is not fully annular, but is interrupted by spaced-apart steps that provide a plurality of interspaced second material crushing sections (5A) disposed above the material inlet section (7).

The term “crushing” as used herein refers to all types of crushing, including primary, secondary, tertiary, and quaternary crushing, pebble and fine crushing, crushing employed in the manufacture of abrasive and non-abrasive sand, cubicising material, and crushing ferro alloys.

Exemplification

The invention will now be described with reference to specific Examples. These are merely exemplary and for illustrative purposes only: they are not intended to be limiting in any way to the scope of the monopoly claimed or to the invention described. These examples constitute the best mode currently contemplated for practicing the invention.

Referring to the drawings, and initially to Figure 1 (comparative) which illustrates a known inner shell (EF mantle) for a Sandvik CH865i crusher. The upper material flow restriction section comprises a plurality of shoulders including a lower shoulder A disposed adjacent to the material inlet section B having a sidewall section C and an arcuate restriction plane section D to slow the entry of material into the material inlet. The outer part E of the restriction plane section is arcuate and radially outwardly inclined at an angle of about 15% to the horizontal when the inner cone is mounted in a cone crusher machine. In addition, the inner shell diameter X1 across the sidewall section of the lower material collection shoulder is about 13% less than an inner shell diameter X2 cross a top of the material inlet section. Referring to Figures 2 to 6, an inner shell according to a first embodiment of the invention, is illustrated, and indicated generally the reference numeral 1. The inner shell is hollow and has a conical profile with a centre line CL that upon assembly is disposed vertically, and comprises a lower material crushing section 5, an upper material flow restriction section 6, and a material inlet section 7 disposed between the lower material crushing section and the upper material flow restriction section. The upper material flow restriction section 6 is designed to restrict the flow of material into the material inlet section and comprises a lower shoulder section 8 disposed adjacent to the material inlet section and an upper shoulder section 13 disposed above the lower shoulder section 8. It will be appreciated that in some embodiments, the inner shell according to the invention will not incorporate an upper shoulder section, or in some embodiments it may include a plurality of stepped upper shoulder section.

Referring to Figures 3 and 4, the lower shoulder section 8 has an annular upright sidewall section 9 and an annular arcuate restriction plane section 10 defined by an arcuate inner transition section 10A and an outer planar section 11 . Referring specifically to Figure 4, the outer planar section 11 of the arcuate restriction plane section 10 is inclined downwardly and outwardly at an angle (0) of about 3° to the horizontal when the inner shell is mounted in a cone crusher. It will be appreciated that the outer planar section may in one embodiment be horizontal, although a shallow incline of less than about 15°, or less than 10°, is preferable. This shallow slope of the shoulder serves to restrict the flow of material into the material inlet section and combined with the area of the shoulder allows the crusher to operate on a smaller minimum setting (close side setting), producing a finer product with less recirculation of oversized material.

The inner transition section 10A curves radially inwardly and upwardly defining a smooth upwardly curved transition between the outer planar section 10 and sidewall section 9. As illustrated in Figures 4 and 5, the restriction plane section has a diameter of D3 (which is combination of the outer planar section 11 and inner transition section 10A as shown in Fig. 4 and the outer planar section 10 has a diameter D4 (as shown in Figure 4). In the embodiment shown, the diameter of the outer planar section D4 is about 40% of the diameter of the entire restriction plane section D3. This relationship between D3 and D4 may vary, and D3 is generally at least 30% of D4 and optionally up to 60% of D4.

Referring to Figure 3, the inner shell diameter D1 across the top of the sidewall sections 9 of the lower shoulder section 8 is 36% less than an inner shell diameter D2 across a top of the material inlet section 7. This provides the lower shoulder section with a greater area for restricting the flow of material into the material inlet section.

Referring to Figure 4 and 5, the inner shell 1 also has an upper shoulder section 13 comprising a restriction plane section 14, wherein a ratio of the width D3 of the restriction plane section 10 of the lower shoulder section 8 to the width D5 of the restriction plane section 14 of the upper shoulder section 13 is at least 2:1 , and ideally about 2.5:1 . Referring to Figure 6, the sidewall section 9 of the lower shoulder section 8 is inclined inwardly slightly, by about 3° to the vertical when the inner shell is mounted in a cone crusher.

Referring to Figure 8, a cone crusher according to the invention and incorporating the inner shell 1 of Figures 2 to 6 is described in which parts described with reference to the Figures 2 to 6 are assigned the same reference numerals. The cone crusher, indicated generally, by the reference numeral 2, comprises an inner shell 1 as described previously mounted on a shaft with a crushing head 15, an outer shell 3 mounted to a frame around the inner shell 1 to provide a crushing chamber 4 between the inner shell 1 and outer shell 3. A drive mechanism 17 is operatively connected to the crushing head 15 for rotation of the inner shell 1 within the outer shell 3 about an eccentric axis to crush material in the crushing chamber. In use, material to be crushed is delivered from above into the crushing gap 4 between the inner shell 1 and outer shell 3, where the gyratory action of the inner shell, and in particular the lower material crushing section, relative to the outer shell will crush the material to a pre-determined size. At least some of the material being delivered into the cone crusher will fall on to the upper material flow restriction section, including the lower shoulder section, which will restrict the flow of material into the material intake allowing the crusher to operate on a smaller minimum setting (close side setting), producing a finer product with less recirculation of oversized material. The construction and operation of cone crushers is described in detail in EP1868726 and EP2818246, the relevant contents of which are incorporated herein by reference, and will not be described in more detail herein.

Referring to Figure 7, an inner shell (for a cone crusher) according to an alternative embodiment of the invention, and indicated generally by the reference numeral 20, is described in which parts described with reference to the previous embodiments are assigned the same reference numerals. In this embodiment, the inner shell 20 has the same basic design as the inner shell 1 described previously, except that the lower shoulder 8 incorporates six spaced apart steps 21 providing a plurality of radially outwardly facing second material crushing sections 5A disposed above the material inlet section 7 interspaced around the lower shoulder 8. Each step generally has a top surface with a planar outer section and an inner arcuate transition section which provides a smooth transition from the outer section to the upright sidewall, side surfaces, and a radially outward facing surface that provides the second material crushing section 5A. The radially outward facing surface is typically radially outwardly inclined so that it is typically substantially co-extensive with an upper region of the material crushing section 5. In the embodiment shown, the steps are shaped to provide rectangular second material crushing sections 5A, although it will be appreciated that the steps may be of any shape as long as they provide material crushing sections that are raised above the primary material crushing section 5. The provision of a plurality of interspaced second material crushing sections disposed above the material inlet section has been found to reduce the wear on the material inlet section, and provide a more constant crushing performance over the lifetime of the inner shell or inner shell liner.

The inner shell of the invention provides a technical advantage of known inner shells by being designed to allow the crusher to operate on a smaller minimum setting (close side setting), producing a finer product with less recirculation of oversized material. This has been achieved by changing the configuration of the lower shoulder section adjacent to the material inlet section to incorporate a shallow inclined outer profile that has an angle of less than 15°, and preferably less than 10°, to the horizontal. In particular, the provision of the arcuate restriction plane section in the form of an inner arcuate transition section and an outer planar section has been found to allow the crusher to operate on a smaller minimum setting (close side setting) compared with cone crushers with inner cones of know design. The Applicant has also discovered that increasing the material flow restriction area by providing a shoulder with a greater width improves the performance of the crusher in the context of a smaller minimum setting.

Although the inner shell of the invention is described primarily with reference to use with cone (gyratory) crushers, it will be appreciated that the inner shell may be used with other types of material crushers that employ crushing shells.

Equivalents

The foregoing description details presently preferred embodiments of the present invention. Numerous modifications and variations in practice thereof are expected to occur to those skilled in the art upon consideration of these descriptions. Those modifications and variations are intended to be encompassed within the claims appended hereto.