WO2011128854A2

WO2011128854A2 - Vertical shaft impact crushers

Info

Publication number: WO2011128854A2
Application number: PCT/IB2011/051593
Authority: WO
Inventors: Gideon Wessels; John Leask Gates Firth
Original assignee: Eriogenix (Pty) Ltd
Priority date: 2010-04-14
Filing date: 2011-04-13
Publication date: 2011-10-20
Also published as: WO2011128854A3

Abstract

A vertical shaft impact crusher, crushing chamber, which includes a cylindrical outer wall, a substantially horizontal annular shaped floor and an outward-, downwardly slanted annular crushing chamber roof with a vertical shaft impact crusher rotor, which includes a blade mounting arrangement rotatable about a central rotation axis, the blade mounting arrangement having at least a bottom disk onto which a feed material is receivable and at least two rotor blades defining vanes mounted onto the bottom disk, the vanes running from a central portion of the rotor towards a periphery of the bottom disk, the rotor blades arranged on a segment of the bottom disk and defining an obtuse angle with the disk plane, mounted into the crushing chamber.

Description

VERTICAL SHAFT IMPACT CRUSHERS

This invention relates to vertical shaft impact crushers. In particular, the invention relates to a vertical shaft impact crusher crushing chamber, a vertical shaft impact crusher modification kit, a vertical shaft impact crusher, to a vertical shaft impact crusher rotor, and to a vertical shaft impact crusher rotor modification kit.

BACKGROUND OF THE INVENTION

The inventor is aware of inventions in the field of Vertical Shaft Impact (VSI) crushers. Vertical shaft impact crushers are used for breaking of rocks, ore, etc.

VSI crusher operates by feeding a feed material by force of gravity axially into a rotating rotor. The rotor has a central feeding section leading from a cone, a tube or the like into an ejection section, which contains openings through the wall of the rotor, with rotor blades disposed next to the openings for ejecting the feed material under centrifugal force outwardly into a crushing chamber.

The rotor is housed in a housing that defines an annular crushing chamber in which the ejection section of the rotor is located. In some VSI crushers, the crushing chamber is shaped to retain an amount of feed material along an outer peripheral wall, which lines the crushing chamber. In other crushers the crushing chamber is configured not to retain any build-up material on the outer peripheral wall of the crushing chamber, in order for the material to come in direct contact with the crusher chamber wall during crushing. In operation, feed material is ejected from the ejection section of the rotor and directed outwardly under centrifugal force by the rotor blades onto the lined crushing chamber wall. Upon hitting the lined or unlined crushing chamber, crushing of the feed material takes place. The build-up of crushed material against the outer peripheral wall of the crushing chamber is continuously disposed as processed material, which has a smaller average diameter as the feed material. The speed of material feed, the speed of disposal of processed material, the ejection speed, the rotational speed of the rotor and the blade configuration control the rate of processing of feed material and the size of processed material. Depending on the application, VSI crushers are used in various applications where the feed material is of different compositions and in applications where material is either dry or damp. However, the inventor found that the rotor blade orientation could be improved to reduce maintenance of the blades. Furthermore, the inventor found that the shape of the crushing chamber could be modified to improve efficiency of the VSI crusher for use with certain types of feed material.

The crushing chamber has a substantially cylindrical outer wall with a substantially horizontal annular crushing chamber roof and a substantially horizontal annular crushing chamber floor. Radially extending gussets are spaced along the peripheral outer wall.

The crushing process operates by creating a toroidal cloud of feed material between the rotating crusher blades and the lining of accumulated feed material along the outer crusher wall.

The crushing chamber roof is often not sealed, providing for the circulation of air and for the cascade feeding of feed material, into the rotor and directly into the crushing chamber.

The ejection sections of conventional rotors are defined by substantially horizontal annular rotor top walls and substantially horizontal circular rotor bottom walls. Substantially radially extending vanes are provided between the rotor top wall and the rotor bottom wall with the rotor blades provided at the outer ends of the vanes. Because of the friction on the vanes and the rotor blades, they are subject to wear. The inventor is aware of prior art related to the design of rotor blades to minimize wear and to control ejection patterns of feed material so as to optimize crushing of feed material.

The inventor found that certain improvements to the rotor vanes and rotor blades could improve the ejection patterns of the feed material and reduce wear on rotor blades.

The inventor had particular difficulties with undesirable build-up of feed material in the crushing chamber related to the dampness of material and the clay content thereof. The present invention aims to address these shortcomings by providing an improved crushing chamber configuration and rotor configuration.

SUMMARY OF THE INVENTION According to one aspect of the invention, there is provided a vertical shaft impact crusher, crushing chamber, which includes

a cylindrical outer wall;

a substantially horizontal annular shaped floor; and

an outward-, downwardly slanted annular crushing chamber roof.

The chamber roof may be slanted to extend at least partly into the ejection path of ejected materials.

In one embodiment of the vertical shaft impact crusher, crushing chamber, the roof may comprise a number of annular roof segments, in combination to define a full annulus. The crushing chamber may include mounting means shaped and dimensioned to receive the annular roof segments.

The mounting means may include dampers for mounting the roof segments.

The dampers may include resilient mounting means. For example, the resilient mounting means may be in the form of elastomeric mountings, such as rubber mountings.

The mounting means may be in the form of cartridges having rubber mountings onto which an annular roof segment can be mounted. The mounting means may thus include a plurality of cartridges circumferentially arranged inside an outer wall of the cylindrical outer wall, the annular roof segments being mountable onto the cartridges.

The crushing chamber may be provided with an annular top seal disposed between a rotor head and the annular roof segments, for sealing the roof segments against the rotor.

In another embodiment of the vertical shaft impact crusher, crushing chamber, the crushing chamber may include moulded roof/sidewall segments, which, when inserted into the crushing chamber defines the outward-, downwardly slanted annular crushing chamber roof and a sidewall lining.

The moulded roof/sidewall segments may be provided with interlocking formations locating the segments in annular spaced relationship with each other.

In yet another embodiment of the vertical shaft impact crusher, crushing chamber, the outward-, downwardly slanted annular crushing chamber roof may be defined by a conically rolled or set bent metal sheet. The crushing chamber may include an annular ring lining a lower portion of the cylindrical outer wall, the ring defining a spacer between the substantially horizontal annular shaped floor and the sheet metal roof. According to another aspect of the invention, there is provided a vertical shaft impact crusher modification kit, which includes at least one outward-, downwardly slanted annular crushing chamber roof closure.

In one embodiment of the vertical shaft impact crusher modification kit, the kit may include a plurality of sectioned roof closures, which, in combination, define full annular crushing chamber roof.

The kit may include a roof closure mounting kit for mounting the sectioned roof closures onto the cylindrical outer wall.

The roof closure mounting kit may be in the form of cartridges having rubber mountings onto which an annular roof segment can be mounted. The mounting kit may thus include a plurality of cartridges operatively to be arranged circumferential ly inside an outer wall of the cylindrical outer wall, the annular roof segments being mountable onto the cartridges.

In another embodiment of the vertical shaft impact crusher modification kit, the kit may include moulded roof/sidewall segments, which, when inserted into the crushing chamber defines the outward-, downwardly slanted annular crushing chamber roof and a sidewall lining.

The moulded roof/sidewall segments may be provided with interlocking formations locating the segments in annular spaced relationship with each other. In another embodiment of the vertical shaft impact crusher modification kit, the kit may include a hot rolled metal sheet that defines the outward, downwardly slanted annular crushing chamber roof. The vertical shaft impact crusher modification kit may include an annular ring for lining a lower portion of the cylindrical outer wall, the ring defining a spacer between the substantially horizontal annular shaped floor and the sheet metal roof.

The vertical shaft impact crusher modification kit may include a rotor closing kit mountable onto a rotor.

The rotor closing kit may include a cylindrical closure, shaped and dimensioned to match a circular top wall of a vertical shaft impact crusher rotor.

The closure may be shaped on the vertical shaft impact crusher rotor top wall to engage an operative inner circumference defined by an inner edge of the annular roof, in which the closure is co-axial with the outer cylindrical wall of the crushing chamber.

The cylindrical closure may include mountings arranged to be mountable to a top wall/roof of a vertical shaft impact crusher rotor. The invention extends to a vertical shaft impact crusher onto which a modification kit has been mounted.

The invention extends further to a vertical shaft impact crusher rotor, which includes

a blade mounting arrangement rotatable about a central rotation axis; and at least two roughly planar rotor blades mounted onto the blade mounting arrangement, in operation to define a circular rotation path about the central rotation axis, the roughly planar rotor blades located proximate a circumference of the circular rotation path, the rotor blades defining leading edges and trailing edges, the leading edges of the rotor blades and their respective trailing edges defining acute inscribed angles relative a radius of the rotation path. The rotor may include feeding vanes extending from a central region of the blade mounting arrangement outwardly towards the rotor blades, the feeding vanes each having a feed-in side and a feed-off side. The feeding vanes may be concave.

The feeding vanes may include at least one transversely extending shoulder at their feed-in sides. The feeding vanes may include at least one transversely extending shoulder, orientated roughly radially from the rotation axis.

At least one transversely extending shoulder located towards a feed-off side of the rotor may be rearwardly slanted. In use, the rearwardly slanted leading edges of the rotor blades will eject feeding material in a slightly upward direction. Advantageously, in the embodiment where the blades are concave, the feed material will be focussed onto the slanted roof.

According to yet another aspect of the invention, there is provided a vertical shaft impact crusher rotor, which includes

a blade mounting arrangement rotatable about a central rotation axis, the blade mounting arrangement having at least a bottom disk onto which a feed material is receivable; and

at least two rotor blades defining vanes mounted onto the bottom disk, the vanes running from a central portion of the rotor towards a periphery of the bottom disk, the rotor blades arranged on a segment of the bottom disk and defining an obtuse angle with the disk plane.

The rotor blades may define a stepped surface between its leading edge and its trailing edge. The feeding vanes may define a feed-in side and a feed-off side. The feeding vanes may include transversely extending shoulders at their feed-in sides. According to another aspect of the invention, there is provided a vertical shaft impact crusher rotor modification kit, which includes

a mounting kit for mounting to a vertical shaft impact crusher rotor between a parallel spaced top- and bottom walls of the rotor; and

at least two roughly planar rotor blades attachable to the mounting kit, the rotor blades mountable between the spaced top- and bottom walls of the rotor proximate a circumference of the disks, with leading edges of the rotor blades and their respective trailing edges defining acute inscribed angles relative a radius of the disk, when mounted onto the rotor.

According to yet another aspect of the invention, there is provided a vertical shaft impact crusher rotor modification kit, which includes

at least two rotor blades attachable to the mounting kit, the rotor blades defining vanes mounted onto the bottom disk, the vanes running from a central portion of the rotor towards a periphery of the bottom disk, the rotor blades arranged on a segment of the bottom disk and defining an obtuse angle with the disk plane. Selected embodiment of the invention will now be described, by way of example only with reference to the following drawing(s):

DRAWING(S) In the drawing(s):

Figure 1 shows a partial sectioned three-dimensional view of a vertical shaft impact crusher crushing chamber and the components of a modification kit, in accordance with an aspect of the invention;

Figure 2 shows a partially sectioned, three dimensional view of a closing kit forming part of the modification kit of Figure 1 ;

Figure 3 shows a sectioned three-dimensional view of a rotor in accordance with an aspect of the invention;

Figure 4 shows a top plan view of the rotor of Figure 3; Figure 5 shows a sectioned three-dimensional view of a rotor in accordance with an aspect of the invention;

Figure 6 shows a top plan view of the rotor of Figure 5;

Figure 7 shows a partial sectioned three-dimensional view of a vertical shaft impact crusher crushing chamber and the components of a modification kit, in accordance with an aspect of the invention;

Figure 8 shows a three-dimensional view of a moulded roof/sidewall segment of the crushing chamber shown in Figure 7;

Figure 9 shows a partial sectioned three-dimensional view of a vertical shaft impact crusher crushing chamber and the components of a modification kit in accordance with an aspect of the invention;

Figure 10 shows a sectioned three-dimensional view of a rotor in accordance with an aspect of the invention; and

Figure 1 1 shows a top plan view of the rotor of Figure 10.

EMBODIMENT OF THE INVENTION

In Figure 1 , there is provided a vertical shaft impact crusher, crushing chamber 10, modified with a modification kit in accordance with the invention.

The crushing chamber 10 includes a cylindrical outer wall 12 surrounding an outward-, downwardly slanted annular crushing chamber roof, generally indicated by reference numeral 14, and a substantially horizontal annular crushing chamber floor 16. The crushing chamber 10 also includes radially extending gussets, which are not shown in the drawing for sake of clarity.

In this example, the roof comprises a number of annular roof segments 14.1 to 14.8 (only 14.1 to 14.5 shown), circumferentially arranged inside the cylindrical outer wall 12, in combination to define a full annulus.

The crushing chamber 10 includes mounting means in the form of cartridges 18.1 to 18.8 (only 18.2 to 18.5 shown) onto which the annular roof segments 14.1 to 14.8 are mounted. The cartridges have slots (not shown) into which the roof segments are slideably receivable.

The cartridges have dampers (not shown) in the form of rubber mat segments lining the slots into which the annular roof segments 14.1 to 14.8 are receivable. The dampers facilitate the vibratory movement of the annular roof segments 14.1 to 14.8.

As can be seen in Figure 1 , a rotor 20 is provided co-axial to the annulus formed by the annular roof segments 14.1 to 14.8. The rotor will be described in more detail with reference to Figures 3 to 6.

An annular top seal 30 of the rotor 20 is described with reference to Figure 2. The top seal 30 is provided on a circular rotor top wall 32. The top wall includes an upright circular steel ridge 33 rigidly attached onto the top wall 32. An inside face and an outside face of the ridge 33 are then lined with rubber strips 34, 36. The rubber strips 34, 36 are attached to the ridge 33 by means of nut and bolt sets 38.1 to 38.6 extending through the rubber strips 34, 36 and through apertures in the ridge 33. The ridge 33 and the rubber strips 34, 36 are partially sectioned for illustration purposes.

In use, the annular top seal 30 seals the top rotor top wall 32 against the inside circular edge of the annular roof segments 14.1 to 14.8. Figures 3 to 6 and 10 to 1 1 show three embodiments of vertical shaft impact crusher rotors 50, 80, respectively.

In Figure 3 one embodiment of a vertical shaft impact crusher rotor 50 is shown. The rotor 50 comprises two parallel spaced circular disks defining a blade mounting arrangement comprising an operative top wall 52 (shown in broken line) and an operative bottom wall 54 respectively. The operative top wall 52 has a centrally located open circular feeding port 56 (shown in broken line). Three rotor blades 58, 60, 62 extend between the spaced parallel circular walls 52, 54. The rotor blades 58, 60, 62 have roughly planar feeding surfaces defining feeding vanes 58.1 , 60.1 , 62.1 , each of which defines feed-in ends proximate the feeding port 56 and feed-off ends proximate the circumference of the disks 52, 54. The circumference of the disks 52, 54 define rotation paths. The feeding vanes 58.1 , 60.1 , 62.1 each have a transversely extending shoulder 58.2,

60.2, 62.2, respectively, at its feed-in end, and a transversely extending rotor blade

58.3, 60.3, 62.3, respectively at its feed-off end. As can be seen in Figure 3, the rotor blades 58.3, 60.3, 62.3 each have rearward slanted leading edges 58.3.1 , 60.3.1 , 62.3.1 , in operation to eject feeding material in a slightly upward direction.

In Figure 4, the vertical shaft impact crusher rotor 50 of Figure 3 is shown in plan view with the top wall 52 removed. Same numerals refer to same components. Importantly, the leading edges 58.3.1 , 60.3.1 , 62.3.1 of the rotor blades 58.3, 60.3, 62.3 and their respective trailing edges define acute inscribed angles relative a radius of the disk as indicated by reference numeral 64.

In Figure 5 another embodiment of a vertical shaft impact crusher rotor 80 is shown. The rotor 80 also comprises two parallel spaced circular disks defining an operative top wall 82 (shown in broken line) and an operative bottom wall 84 respectively. The operative top wall 82 has a centrally located open circular feeding port 86 (shown in broken line).

Three rotor blades 88, 90, 92 extend between the spaced parallel circular walls 82, 84. The rotor blades 88, 90, 92 have roughly planar feeding surfaces defining feeding vanes 88.1 , 90.1 , 92.1 , each of which defines feed-in ends proximate the feeding port 86 and feed-off ends proximate the circumference. The feeding vanes 88.1 , 90.1 , 92.1 each have a trailing vane 88.2, 90.2, 92.2, respectively, extending beyond its feed-in end, and a transversely extending rotor blade 88.3, 90.3, 92.3, respectively at its feed-off end. The rotor blades 88.3, 90.3, 92.3 are each removably mounted in a cartridge 94, 96, 98, each defined by two parallel spaced panels. In Figure 6, the vertical shaft impact crusher rotor 80 of Figure 5 is shown in plan view with the top wall 82 removed. Same numerals refer to same components. Importantly, the leading edges 88.3.1 , 90.3.1 , 92.3.1 of the rotor blades 88.3, 90.3, 92.3 and their respective trailing edges define acute inscribed angles relative a radius of the disk as generally indicated by reference numeral 100.

In Figure 10 yet another embodiment of a vertical shaft impact crusher rotor 100 is shown. The rotor 100 also comprises two parallel spaced circular disks defining an operative top wall 102 (shown in broken line) and an operative bottom wall 104 respectively. The operative top wall 82 has a centrally located open circular feeding port 106 (shown in broken line).

Three rotor blades 108, 1 10, 1 12 extend between the spaced parallel circular walls 102, 104. The rotor blades 108, 1 10, 1 12 have stepped feeding surfaces defining feeding vanes 108.1 , 1 10.1 , 1 12.1 , each of which defines feed-in ends proximate the feeding port 106 and feed-off ends proximate the circumference. The feeding vanes 108.1 , 1 10.1 , 1 12.1 each have a trailing vane 108.2, 1 10.2, 1 12.2, respectively, extending beyond its feed-in end. The feeding vanes have stepped linings 108.3, 1 10.3 and 1 12.3.

In Figure 1 1 , the vertical shaft impact crusher rotor 100 of Figure 10 is shown in plan view with the top wall 102 removed. Same numerals refer to same components. Importantly, as can be seen in top view, the feeding vanes 108.1 , 1 10.1 , 1 12.1 defined by the rotor blades 108, 1 10, 1 12 that are mounted on the bottom disk, are at obtuse angles with the disk 104 plane on which they are mounted.

In use, the obtuse angle of the rotor blades 108, 1 10, 1 12 will eject feeding material in a slightly upward direction.

In Figure 7 a vertical shaft impact crusher crushing chamber 120 and the components of a modification kit is shown. The crushing chamber 120 includes a cylindrical outer wall 122 surrounding an outward-, downwardly slanted annular crushing chamber roof, generally indicated by reference numeral 124, and a substantially horizontal annular crushing chamber floor (not shown).

In this example, the roof comprises a number of moulded annular roof/sidewall segments 124.1 to 124.8 (only 124.1 to 124.6 shown), circumferentially arranged inside the cylindrical outer wall 122, in combination to define a full annular roof and a complete sidewall lining.

As can be seen in Figure 8, one moulded annular segment 124.6 includes a roof portion 124.6.1 and a sidewall lining section 124.6.2 with interlocking formations 124.6.3, 124.6.4 which fit into adjacent interlocking formations to locate the annular segments 124 into the chamber 120.

As can be seen in Figure 7, a rotor 100 is provided co-axial to the annulus formed by the annular roof segments 124.1 to 124.8.

In Figure 9 a vertical shaft impact crusher, crushing chamber 130 and the components of a modification kit in accordance with another aspect of the invention is shown.

The crushing chamber 130 includes a cylindrical outer wall 132 surrounding an outward-, downwardly slanted annular crushing chamber roof, generally indicated by reference numeral 134, and a substantially horizontal annular crushing chamber floor (not shown).

The roof 134 rests on a circular ring 136 mounted inside the outer wall

132.

In this example, the roof 134 is of a single hot rolled metal plate, which is outward-, downwardly slanted, and which rests on the annular ring 136. Although not illustrated in these examples, the annular roof components, the annular top seal of the rotor and the rotor blades can be supplied in a kit form, used to modify existing vertical shaft impact crushers. Some of the components can also be provided as replacement parts in event of component wear.

The inventor believes that the invention, as described and illustrated provides a new vertical shaft impact crusher crushing chamber, a vertical shaft impact crusher modification kit, a vertical shaft impact crusher, a vertical shaft impact crusher rotor, and a vertical shaft impact crusher rotor modification kit. The modifications are of particular use in circumstances where the feed material is damp and where the feed material has high clay content. The annular roof segments, mounted on dampers facilitate the reduction of feed material build-up. The modifications to the rotor blades reduce wear on the blades and the closing kit reduces clogging of feed material due to re-introduction of feed material into the rotor.

Claims

CLAIMS:

1 . A vertical shaft impact crusher, crushing chamber, which includes

a cylindrical outer wall;

a substantially horizontal annular shaped floor; and

an outward-, downwardly slanted annular crushing chamber roof.

2. A crushing chamber as claimed in claim 1 , in which the chamber roof is slanted to extend at least partly into the ejection path of ejected materials.

3. A crushing chamber as claimed in claim 1 , in which the roof comprise a number of annular roof segments, in combination to define a full annulus.

4. A crushing chamber as claimed in claim 3, which includes mounting means shaped and dimensioned to receive the annular roof segments.

5. A crushing chamber as claimed in claim 4, in which the mounting means include dampers for mounting the roof segments.

6. A crushing chamber as claimed in claim 5, in which the dampers include resilient mounting means.

7. A crushing chamber as claimed in claim 6, in which the mounting means is in the form of cartridges having rubber mountings onto which an annular roof segment can be mounted.

8. A crushing chamber as claimed in claim 3, which is provided with an annular top seal disposed between a rotor head and the annular roof segments, for sealing the roof segments against the rotor.

9. A crushing chamber as claimed in claim 1 , which includes moulded roof/sidewall segments, which, when inserted into the crushing chamber, define the outward-, downwardly slanted annular crushing chamber roof and a sidewall lining.

10. A crushing chamber as claimed in claim 9, in which the moulded roof/sidewall segments are provided with interlocking formations locating the segments in annular spaced relationship with each other.

1 1 . A crushing chamber as claimed in claim 1 , in which the outward, downwardly slanted annular crushing chamber roof is defined by a conically rolled or set bent metal sheet.

12. A crushing chamber as claimed in claim 1 1 , which includes an annular ring lining a lower portion of the cylindrical outer wall, the ring defining a spacer between the substantially horizontal annular shaped floor and the sheet metal roof.

13. A vertical shaft impact crusher modification kit, which includes at least one outward-, downwardly slanted annular crushing chamber roof closure.

14. A vertical shaft impact crusher modification kit as claimed in claim 13, which includes a plurality of sectioned roof closures, which, in combination, define a full annular crushing chamber roof.

15. A vertical shaft impact crusher modification kit as claimed in claim 14, which includes a roof closure mounting kit for mounting the sectioned roof closures onto the cylindrical outer wall.

16. A vertical shaft impact crusher modification kit as claimed in claim 15, in which the roof closure mounting kit is in the form of cartridges having rubber mountings onto which an annular roof segment can be mounted.

17. A vertical shaft impact crusher modification kit as claimed in claim 13, which includes moulded roof/sidewall segments, which, when inserted into the crushing chamber, define the outward-, downwardly slanted annular crushing chamber roof and a sidewall lining.

18. A vertical shaft impact crusher modification kit as claimed in claim 17, in which the moulded roof/sidewall segments are provided with interlocking formations locating the segments in annular spaced relationship with each other.

19. A vertical shaft impact crusher modification kit as claimed in claim 13, which includes a conically rolled or set bent metal sheet that defines the outward-, downwardly slanted annular crushing chamber roof.

20. A vertical shaft impact crusher modification kit as claimed in claim 19, which includes an annular ring for lining a lower portion of the cylindrical outer wall, the ring defining a spacer between the substantially horizontal annular shaped floor and the sheet metal roof.

21 . A vertical shaft impact crusher modification kit as claimed in claim 13, which includes a rotor closing kit mountable to a rotor.

22. A vertical shaft impact crusher modification kit as claimed in claim 21 , in which the rotor closing kit includes a cylindrical closure, shaped and dimensioned to match a circular top wall of a vertical shaft impact crusher rotor.

23. A vertical shaft impact crusher modification kit as claimed in claim 22, in which the closure is mounted onto the vertical shaft impact crusher rotor top wall to engage an operative inner circumference defined by an inner edge of the annular roof closures, in which the closure is co-axial with the outer cylindrical wall of the crushing chamber.

24. A vertical shaft impact crusher modification kit as claimed in claim 23, in which the cylindrical closure includes mountings arranged to be mountable to a top wall/roof of a VSI crusher rotor.

25. A vertical shaft impact crusher onto which a modification kit as claimed in any one of claims 13 to 24 has been mounted.

26. A vertical shaft impact crusher rotor, which includes

a blade mounting arrangement rotatable about a central rotation axis; and at least two roughly planar rotor blades mounted onto the blade mounting arrangement, in operation to define a circular rotation path about the central rotation axis, the roughly planar rotor blades located proximate a circumference of the circular rotation path, the rotor blades defining leading edges and trailing edges, the leading edges of the rotor blades and their respective trailing edges defining acute inscribed angles relative a radius of the rotation path.

27. A vertical shaft impact crusher rotor as claimed in claim 26, which includes feeding vanes extending from a central region of the blade mounting arrangement outwardly towards the rotor blades, the feeding vanes each having a feed-in side and a feed-off side.

28. A vertical shaft impact crusher rotor as claimed in claim 27, in which the feeding vanes include transversely extending shoulders at their feed-in sides.

29. A vertical shaft impact crusher rotor as claimed in claim 28, in which each of the feeding vanes includes at least one transversely extending shoulder, arranged roughly radially from the rotation axis.

30. A vertical shaft impact crusher rotor as claimed in claim 29, in which a transversely extending shoulder located towards a feed-off side of the rotor vane is rearwardly slanted.

31 . A vertical shaft impact crusher rotor as claimed in claim 27, in which the feeding vanes are concave.

32. A vertical shaft impact crusher rotor, which includes

a blade mounting arrangement rotatable about a central rotation axis, the blade mounting arrangement having at least a bottom disk onto which a feed material is receivable; and at least two rotor blades defining vanes mounted onto the bottom disk, the vanes running from a central portion of the rotor towards a periphery of the bottom disk, the rotor blades arranged on a segment of the bottom disk and defining an obtuse angle with the disk plane.

33. A vertical shaft impact crusher rotor as claimed in claim 32, in which the rotor blades define a stepped surface between its leading edge and its trailing edge.

34. A vertical shaft impact crusher rotor as claimed in claim 32, in which the feeding vanes define a feed-in side and a feed-off side.

35. A vertical shaft impact crusher rotor as claimed in claim 34, in which the feeding vanes include transversely extending shoulders at their feed-in sides.

36. A vertical shaft impact crusher rotor as claimed in claim 32, in which the vanes are concave.

37. A vertical shaft impact crusher rotor modification kit, which includes a mounting kit for mounting to a vertical shaft impact crusher rotor between a parallel spaced top- and bottom walls of the rotor; and

38. A vertical shaft impact crusher rotor modification kit, which includes a mounting kit for mounting to a vertical shaft impact crusher rotor between a parallel spaced top- and bottom walls of the rotor; and

at least two rotor blades attachable to the mounting kit, the rotor blades defining vanes mounted onto the bottom disk, the vanes running from a central portion of the rotor towards a periphery of the bottom disk, the rotor blades arranged on a segment of the bottom disk and defining an obtuse angle with the disk plane.

39. A vertical shaft impact crusher rotor as claimed in claim 38, in which the feeding vanes are concave.

40. A vertical shaft impact crusher as claimed in any one of claims 1 and 25, substantially as herein described and illustrated.

41 . A vertical shaft impact crusher modification kit as claimed in claim 13, substantially as herein described and illustrated.

42. A vertical shaft impact crusher rotor as claimed in any one of claims 26 and 32, substantially as herein described and illustrated.

43. A vertical shaft impact crusher rotor modification kit as claimed in any one of claims 37 and 38, substantially as herein described and illustrated.

44. A new vertical shaft impact crusher, a new vertical shaft impact crusher modification kit, a new vertical shaft impact crusher rotor and a new vertical shaft impact crusher rotor modification kit, substantially as herein described.