WO2003035262A1

WO2003035262A1 - Stepped rotor

Info

Publication number: WO2003035262A1
Application number: PCT/NL2002/000677
Authority: WO
Inventors: Johannes Petrus Andreas Josephus Van Der Zanden
Original assignee: Van Der Zanden, Rosemarie, Johanna
Priority date: 2001-10-25
Filing date: 2002-10-24
Publication date: 2003-05-01

Abstract

The device according to the invention relates to a rotor that can be rotated in at least one direction of rotation about an axis of rotation, which rotor is provided with a rotor surface and with a receiving and distributing member, which receiving and distributing member is provided on the top with a receiving and distributing surface, the outer edge of which extends in a regular manner around the axis of rotation, such that the outer edge of the rotor surface is at least partially a greater radial distance away from said axis of rotation than the outer edge of said receiving and distributing surface, at least that part of the rotor surface that extends between the outer edge of the receiving and distributing member and the outer edge of the rotor surface being a greater distance away from the plane of movement than said outer edge of said receiving and distributing surface.

Description

STEPPED ROTOR

FIELD OF THE INVENTION

The invention relates to the field of the acceleration of material, in particular a stream of granular or particulate material, with the aid of centrifugal force, with, in particular, the aim of causing the accelerated grains or particles to collide with at least one rotating impact member at such a velocity that they break.

BACKGROUND TO THE INVENTION

According to a known technique the movement of a stream of material can be accelerated with the aid of centrifugal force. With this technique the material is fed onto the central part (the circular feed surface of a receiving and distributing member) of a rapidly rotating rotor and is then picked up by one or more accelerator members which are carried by said rotor with the aid of a support member and are provided with an acceleration surface that extends from the outer edge of said feed surface towards the outer edge of the rotor between the central feed and the take-off end of the accelerator member. The fed material is picked up from the receiving and distributing member by the central feed, then accelerated along the acceleration surface under the influence of centrifugal force and thereafter, when the accelerated material leaves the accelerator member at the location of the take-off end, propelled outwards at high velocity. Viewed from a stationary standpoint, after it leaves the accelerator member, the material moves at virtually constant velocity along a virtually straight stream that is directed forwards. Viewed from a standpoint moving with the accelerator member, after it leaves the accelerator member, the material moves in a spiral stream that is directed backwards, viewed in the direction of rotation; during this movement the (relative) velocity increases along said spiral path as the material moves further away from the axis of rotation.

The accelerated material can now be collected by a stationary impact member that is arranged in the straight stream that the material describes, with the aim of causing the material to break during the collision. The stationary impact member can, for example, be formed by an armoured ring that is arranged centrally around the rotor. The material strikes the stationary impact member at virtually the velocity that it has when it leaves the rotor. The comminution process takes place during this single impact, the equipment being referred to as a single impact crusher.

Instead of allowing the material to impinge directly on a stationary impact member, it is also possible first to allow the material to impinge on the impact surface of a co-rotating impact member associated with the accelerator member, which co-rotating impact member is carried by the rotor and is arranged a greater radial distance away from the axis of rotation than is the guide member, with the i pact surface oriented transversely to the spiral stream, with the aim of allowing the material to collide once before the material strikes the stationary impact member. The material strikes the co- rotating impact member (impact surface) at the (relative) velocity that the material develops along the spiral path, the material being simultaneously loaded and accelerated during the impact, with which velocity the material is then loaded for a second time when it strikes the stationary impact member. With this arrangement there is said to be a direct multiple impact crusher, which has a very much higher comminution intensity than a single impact crusher. A direct multiple impact crusher of this type is disclosed in PCT/NL97/00565, which was drawn up in the name of the Applicant. The rotor of the direct multiple impact crusher can also be of symmetrical construction, which makes it possible to allow the rotor to operate in both directions. A device of this type is disclosed in PCT/NL00/00668, which was drawn up in the name of the Applicant. Both devices are of particular importance with regard to the invention.

The known rotor has the advantage that the material is simultaneously loaded and accelerated during the impact on the co-rotating impact surface, which loading, moreover, takes place completely free from disturbance. The known rotor consequently has a high comminution intensity.

However, the known rotor also has disadvantages. For instance, intense wear occurs because the fed material scrapes over the rotor surface at high velocity - which rotor surface is of essentially straight construction in the known rotor - and this wear relates to [TJ intense guide wear along that section of the rotor surface that extends between the guide and the impact member over which the material moves along a spiral path, the velocity at which the material scrapes over this section of the rotor surface increasing progressively along said spiral path, [Uj intense guide and impact wear along the section of the rotor surface that extends along the front of the impact surface and [ITf] intense guide wear along the section of the rotor surface that extends between the impact surface and the location along the outer edge of the rotor where the material is propelled outwards from the rotor. This wear makes it necessary to protect the rotor surface with wear plates that have to be regularly replaced, whilst the movement along the spiral path can be disturbed by the scraping action along the rotor blade and the same applies for the impact of the material on the impact surface. This can result in the cornminution intensity or the probability of break being reduced. Another disadvantage of the known rotor is that this rotor - in a specific embodiment - can be used for only one - or at least a limited number of - applications: that is, with a specific configuration it is possible accurately to adjust the co-rotating impact velocity, but not the intensity behaviour of the impact. For other applications, for which a different configuration (intensity behaviour) is required or is more effective, a completely new rotor has to be installed. For example, if it is desired to allow impingement against the co-rotating impact to proceed autogenously (that is on a bed of own material) instead of on a metal impact surface, because the latter gives rise to impact behaviour that is too intensive. AJM OF THE INVENTION

The aim of the invention is, therefore, to provide a simple rotor as described above that do not have the said disadvantages, or at least display these to a lesser extent, that is to say that the wear on the section of the rotor blade between the guide member and the impact member, along the front of the impact member and between the impact member and the outer edge of the rotor is prevented or at least is reduced. To this end the invention provides a device for causing a stream of granular material that is moving along a plane of movement that is coincident with the plane of rotation to accelerate and to collide, comprising: - a rotor that can be rotated about an axis of rotation in at least one direction of rotation, which rotor is provided with a central part and on the top with a rotor surface, the outer edge of which extends regularly around the axis of rotation, such that the centre of the rotor surface is coincident with the axis of rotation, which rotor is supported on a shaft, the shaft axis of which is coincident with the axis of rotation; - a receiving and distributing member that is carried by the central part in such a way that the receiving and distributing member can be removed for replacement because of wear, which receiving and distributing member is provided on the top with a receiving and distributing surface, the outer edge of which extends in a regular manner around the axis of rotation in such a way that the central part of the receiving and distributing surface is coincident with the axis of rotation and in such a way that the outer edge of the rotor surface is at least partially a greater radial distance away from the axis of rotation than is the outer edge of the receiving and distributing surface, for receiving and distributing the material that is fed with the aid of a feed member onto the rotor at a location close to the axis of rotation;

- at least one guide member that is carried by the rotor in such a way that the guide member can be removed for replacement because of wear, which guide member is located some distance away from the axis of rotation and is provided with at least one guide surface that extends in the direction of the outer edge of the rotor, which guide surface is provided with a central feed and a release end, the outer edge of which receiving and distributing surface at least extends as far as the release end, for, respectively, picking up the fed material from the receiving and distributing surface by the central feed, guiding the picked-up material along the guide surface under the influence of centrifugal force, after which the guided material is directed, when it leaves the guide member at the location of the release end, into a spiral path directed backwards, viewed in the direction of rotation and viewed from a standpoint moving with the guide member, the material moving between the guide member and the impact member along or through a plane of movement that is essentially coincident with or runs parallel to the plane of rotation;

- at least one impact member that is carried by the rotor at a location between the outer edge of the receiving and distributing surface and the outer edge of the rotor surface, in such a way that the impact member can be removed for replacement because of wear, which impact member is provided with an impact surface that is associated with the guide member, in such a way that at least one impact part of the impact surface is oriented essentially transversely to the spiral path, viewed in the direction of rotation and viewed from a standpoint moving with the impact member for causing the material to collide, after which, when it leaves the impact member, the material that has collided once is directed into a straight path directed forwards, viewed in the direction of rotation and viewed from a stationary standpoint;

- the rotor rotating about a vertical or non-vertical (horizontal) axis of rotation and the spiral path moving along a plane of movement (disc) that is essentially coincident with (or runs parallel to) the plane of rotation, at least that part of the rotor surface that extends between the outer edge of the central part and the outer edge of the rotor surface being located a greater distance away from the plane of movement than the outer edge of the central part;

- or, if the rotor rotates about a vertical axis of rotation, at least that part of the rotor surface that extends between the outer edge of the central part and the outer edge of the rotor surface is located at a level below the outer edge of the central part;

- it can also be stated that at least that part of the rotor surface that extends between the outer edge of the central part and the outer edge of the rotor surface is located a greater distance away from the feed member than the outer edge of the central part. The rotor according to the invention is further described in the claims, to which reference is made here.

Here material is understood to be a fragment, grain or a particle, or a stream of fragments, grains or particles, i.e. irregularly shaped material, designated in general here as material.

What is achieved with the rotor according to the invention is that the accelerated material moves, i.e. flies, through the space between the outer edge of the receiving and distributing member and the impact surface - thus moves at a level above the rotor surface (peripheral surface) — as a result of which the material [1] does not scrape, or at least scrapes to a lesser extent, over this part of the rotor surface, so that less wear occurs on the part of the rotor surface that extends between the guide member and the impact member, (II) the movement of the material along the spiral path and the impact on the impact surface are not disturbed, or at least are disturbed to a lesser extent, by wear, [in] less wear occurs on the section of the rotor blade along the front of the impact surface and [IV] no wear, or at least less wear, occurs on the part of the rotor blade that extends between the impact surface and the location along the outer edge of the rotor from where the material is propelled outwards from the rotor. Assuming a vertical axis of rotation, the invention relates to a rotor, the receiving and distributing surface of which, which extends around the axis of rotation, is located at a level above that part of the rotor blade that extends around said receiving and distributing surface, or receiving and distributing member, i.e. is located above that part of the rotor blade that extends between the outer edge of the receiving and distributing surface and the outer edge of the rotor. This difference in height can be achieved by providing the rotor with a central part, the central part surface of which extends around the axis of rotation and is at a level above that part of the rotor surface that extends around said central part, which central part can form a whole with the rotor (optionally welded on) or consists of a separate (individual) part that is carried by the rotor (fixed in or bolted), which central part supports the receiving and distributing member, with or without the aid of an adjusting plate.

The difference in height (X) between the outer edge of the receiving and distributing member (or the receiving and distributing surface) and the peripheral surface that extends between the outer edge of the receiving and distributing surface and the outer edge of the rotor can be chosen to be so large that the impact member is reversible with respect to the plane of rotation. To this end the impact member is provided with two impact surfaces located one above the other, by which means the tool life is doubled and, moreover, it is made possible for a larger portion of the wear material to be used effectively, as a result of which the wear costs are reduced. In the same way the invention provides the option that the impact member is reversible with respect to a plane that runs parallel to the axis of rotation; to this end the impact member is provided with two impact surfaces located alongside one another, the impact surface that is the greatest radial distance away from the axis of rotation being oriented transversely to the spiral path. The invention also provides the option that the impact member is of V-shaped construction - with the point facing inwards or outwards - the impact member being provided with two impact surfaces for each direction of rotation, whilst each of these impact surfaces can, in turn, be provided with two impact surfaces, so that the V-shaped impact member is also reversible with respect to the plane of rotation. To this end the invention provides the option that the impact member is provided, along the side by means of which it is carried by the rotor or the support member, with a metal plate that has an appreciably higher tensile strength than the remainder of the impact member, i.e. the impact block, which metal plate acts as a reinforcing part that is firmly joined to the impact member, in this case impact block. Such a reinforcing plate makes it possible to subject the impact member to heavy loading, that is to allow coarse, hard material to impact at high velocity (for example to allow river gravel 100 mm in size to impact at a velocity of 60 m/sec). The high tensile strength of the metal plate furthermore makes it possible to provide this with a simple clamping construction for fixing to the support member, for example a hook. The reinforcing part (metal plate) can be oriented transversely to the direction of movement of the material along the spiral path, but can also run parallel to this direction of movement. In the latter case it is possible to construct the impact member in such a way that no damage to the metal plate can occur; this is discussed in more detail further below.

The invention also provides the option that the impact member is constructed with a self- rotating impact surface; with this arrangement it is preferable to support this self-rotating impact surface with the aid of a shaft at a level above that part of the rotor blade that extends around said receiving and distributing surface (peripheral surface), what is achieved by this means being that the forces on the shaft are limited. In a similar manner the invention provides the option that the guide member is constructed with a self-rotating guide surface, the location on the rotor where the central feed, the guide surface and the release end are located being determined, but this location shifting with the movement (rotation) of the guide surface.

The invention also provides the option that the impact member is constructed with an autogenous impact surface. To this end the impact member is provided with a cavity that extends along the impact surface in the direction of the outer edge of the rotor, in such a way that material is able to deposit in this cavity under the influence of centrifugal force. In a similar way the invention provides the option that the guide member is constructed with an autogenous guide surface.

To be really effective, the magnitude of the difference in height (X) is determined by, inter alia, [IJ the diameter of the grains that have to be accelerated (i.e. are transported through the space from the guide member to the impact member), [ITJ by the rotor diameter or [JTJ] the diameter of the receiving and distributing member, [TV] the number of guide members, [V] the capacity and [VI] the rotational velocity. It is therefore not possible to indicate an unambiguous difference in height; this difference can range from less than 5 mm to more than 200 mm. In any event the invention provides the option that the difference in height, i.e. the distance between the outer edge of the receiving and distributing surface and the rotor surface respectively, is at least 25 mm, 50 mm, 100 mm or 200 mm, but lower and higher values can be effective or optimum.

To limit wear, it is important that the distance (length) that the material travels over the receiving and distributing member is as small as possible. To this end the invention provides the option: - that the outer edge of the rotor surface is, all round, a greater radial distance away from the rotor axis than the outer edge of the receiving and distributing surface, the receiving and distributing surface being provided with a step (an upright edge) that extends between the outer edge of the receiving and distributing surface and the rotor surface;

- that (and this is preferred) the outer edge of the receiving and distributing surface extends along the central feed and from the central feed along at least part of the guide surface. With this arrangement the invention provides the option that the radius of the circle that the outer edge of the receiving and distributing surface describes is greater than the radial distance from the axis of rotation to the central feed, but the invention also provides the option that the radius of the circle that the outer edge of the receiving and distributing surface describes is less than the radial distance from the axis of rotation to the take-off end.

The invention provides the option that, when the rotor is equipped with a central part, the central surface of said central part describes a circle. The receiving and distributing surface usually describes an essentially identical outer edge as said central surface, but can also project completely or partially over the outer edge of the central part or can remain inside this. The decisive factor here is the effectiveness of the feed from the receiving and distributing member to the guides and the maximum possible limitation of wear and the quantity of structural material.

The invention also provides the option that the central surface describes a regular polygonal shape, the rotor being provided with a guide member at a location close to each of the corners of the polygon (what is achieved by this means being that the path that the material has to travel over the central part - i.e. receiving and distributing member - is limited, and thus the wear is limited, whilst less structural material is needed). For example, the central surface can describe an essentially square shape, the rotor being provided with four guide members which are arranged at a location close to the corners of the square-shaped central surface. The central surface can also describe an elongated shape, the rotor being provided with two guide members that are arranged at a location close to the ends of the central surface of elongated shape. For all cases the impact members here are of symmetrical construction, that is to say with two impact surfaces oriented forwards and backwards in the direction of rotation.

In the same way the invention provides the option that the rotor surface essentially describes a polygon, for example a square shape, the rotor being provided with four impact members that are arranged at a location close to the corners of the square-shaped rotor surface. In a similar manner the rotor surface can describe an elongated shape, the rotor being provided with two impact members that are arranged at a location close to the ends of the rotor surface of elongated shape. Usually the shape that the outer edge of the rotor describes will be identical to the shape that the outer edge of the receiving and distributing surface describes, but this is not essential. Here again, the effectiveness, the limitation of wear and the restriction in the quantity of structural material required are the determining factors for the choice of the shape. Certainly in the case of a symmetrical construction (that is to say with symmetrical guide and impact members) the points of the respective polygons will be coincident with the radial plane from the axis of rotation, but the points of the rotor can also lie precisely between the points of the receiving and distributing surface. The symmetry is the determining factor here, as will be explained below. The invention provides the option that the guide members are carried by the central part or by the receiving and distributing member. The invention also provides the option that the guide members can be removed individually, but can also be removed together (for example as a cassette) with the receiving and distributing member.

As far as the symmetry is concerned, the invention provides the option that the guide member is mirror symmetrical with respect to the radial plane of symmetry from the axis of rotation, such that the guide member functions in both directions of rotation, that the impact member is mirror symmetrical with respect to a plane of symmetry, such that the impact surface, which essentially is of straight construction, is provided with an impact part on both sides of the plane of symmetry.

As far as reversibility of the impact members is concerned, the invention provides the option that [I] the impact member is mirror symmetrical with respect to a plane of symmetry that runs parallel to the plane of rotation, such that the impact member is reversible with respect to said rotational plane of symmetry, the distance between the outer edge of the receiving and distributing surface and the outer edge of the peripheral surface is chosen to be sufficiently large that the impact part that is furthest removed from the rotor is oriented essentially transversely to the spiral path, and that [IT] the impact member is mirror symmetrical in the longitudinal direction, i.e. with respect to the plane of symmetry is oriented transversely to the radial plane from the axis of rotation, such that the impact member is reversible with respect to said transverse plane of symmetry, the upper impact part being oriented essentially transversely to the spiral path. The options for allowing the rotor to rotate in two directions and making the impact members reversible together make the tool life, i.e. the time between replacement of the impact members because of wear, four times longer. As far as the impact member with a self-rotating impact surface is concerned, the invention provides the option that the self-rotating impact surface essentially describes a surface of revolution, the axis of revolution of which runs essentially parallel to the axis of rotation and is coincident with the axis of rotation of the self-rotating impact surface. It can, however, be preferable that the axis of revolution is oriented a few degrees (1-3°) inwards in the direction of the axis or rotation, so that the self-rotating impact member is able to anchor itself under the influence of centrifugal force.

The invention provides the option that the guide members are covered by an annular plate, what is achieved by this means being that the inlet pipe (bottom section of the feed member) does not wear out and the material is fed even better to the guide members. To this end the rotor can be provided with an annular plate, the outer edge of which extends in a regular manner around the axis of rotation and is at a level above the receiving and distributing surface, which annular plate is provided with a circular feed opening, the centre of which is coincident with the axis of rotation, and is supported by the guide member. The invention provides the option that the guide member can be removed together with the annular plate and also provides the option that the guide member can be removed together with the annular plate and/or together with the receiving and distributing member, in all cases optionally as a cassette.

The invention also provides the option that the rotor is equipped with more than one guide member, each of which is provided with a support member, which support members are joined to one another along the top with the aid of an annular member that extends in a regular manner around the axis of rotation, such that the centre of the annular member is coincident with the axis of rotation, it being possible for the annular member to be provided with a wear-resistant annular wall (disc) to protect the annular member from wear, which annular wall consists of at least one piece and can be P T/NL02/00677

- 9 - removed and is so constructed that the annular wall anchors itself against the annular member under the influence of centrifugal force. An annular member of this type strengthens the support members, which can now be of slimmer construction.

The invention provides the option that instead of being of open construction, that is to say with a rotor blade on which the guide members and impact members are arranged (or of semi-closed construction where the guide members are provided with an annular plate or annular member), the rotor can be of closed construction, that is in the form of a sandwich construction of two rotor blades, between which the guide members and impact members are arranged. To this end the rotor is provided with a first rotor blade and a second rotor blade, which first rotor blade is supported on the shaft and carries the receiving and distributing surface, which second rotor blade is some distance away from the first rotor blade, parallel to the first rotor blade, is carried by the first rotor blade and is provided with a circular feed opening, the circle centre of which is coincident with the axis of rotation for feeding the material onto the receiving and distributing surface, which first rotor blade is provided on the top with a first rotor surface and which second rotor blade is provided on the bottom with a second rotor surface, the outer edge of the second rotor surface describes a peripheral shape that is essentially identical to the peripheral shape of the second rotor blade. Here again, the effectiveness and the limitation of wear and the structural material are the determining factors for the choice of the construction (design). In this context the invention provides the option that the second rotor blade is provided on the bottom with a second step (upright edge) that divides the second rotor blade into a second central surface that extends between the outer edge of the feed opening and a second step and a second peripheral surface that extends between the second step and the outer edge of the second rotor surface, in such a way that the second peripheral surface is at a level above the outer edge of the second central surface or, in the case of a non-vertical axis of rotation, a greater distance away from the plane of movement than the second central surface. By this means, instead of a single stepped rotor, essentially a double stepped rotor is produced. Such a rotor can, in particular, be of interest - for limiting wear - when the shaft is not arranged in the vertical direction, specifically is arranged horizontally.

To increase (prolong) the tool life, the invention provides the option that parts of the rotor that are subject to (intense) wear are at least partially provided with a material or element having a greater wear resistance than the remainder.

To this end the invention provides the option that the impact member is provided with a metal impact surface or impact part, it being possible for the impact surface or impact part to be at least partially formed by hard metal or by ceramic material, whilst the impact surface or impact part can also consist entirely of hard metal or ceramic material. The invention also provides the option that the impact surface or impact part is at least partially formed by an autogenous bed of own material.

The invention provides the option that the central feed and/or the release end of the guide P T/NL02/00677

- 10 - member and, respectively, the guide surface is/are made of metal and optionally can partially consist of hard metal or ceramic material. The invention also provides the option that the guide surface is at least partially formed by an autogenous bed of own material.

The invention provides the option that the receiving and distributing surface is made of metal or the receiving and distributing member can be at least partially made of hard metal or ceramic material or at least partially formed by an autogenous bed of own material.

The invention provides the option that that part of the rotor surface that extends between the outer edge of the receiving and distributing member and the outer edge of the rotor is at least partially formed by an autogenous bed of own material and/or is at least partially formed by hard metal or ceramic material.

Hard metal is understood to be an alloy of at least one hard, wear-resistant constituent in the form of tungsten carbide or titanium carbide and at least one soft metal constituent in the form of cobalt, iron or nickel.

Here ceramic material is understood to be a material that at least partially consists of aluminium oxide (corundum - Al₂O₃) and/or at least partially consists of silicon oxide (SiO₂), but here ceramic material can also be understood to be materials such as carbides and silica sand.

The invention also provides the option that the guide member is associated with more than one impact member that are arranged, essentially one after the another, different radial distances away from the axis of rotation, such that the spiral path that the material describes when it leaves the first impact member is oriented transversely to the impact surface of the second impact member, viewed from a standpoint moving with said rotor. The material is thus accelerated on the rotor in two steps - with two strikes -, the impact velocity during the second impact being (much) greater than that during the first impact, by means of which a (very) high comminution intensity is achieved in a simple manner. The invention provides the option that the support member - for both the impact member and the guide member — is removable [T for replacement because of damage or wear and [H] for replacement by a support member that is able to support a different type of impact member or guide member. For example an autogenous member instead of a metal member, or a self-rotating member instead of an autogenous member, or a symmetrical member instead of a non-symmetrical member or member that is symmetrical in some other way, what is achieved by this means being that the rotor is universal and suitable for carrying several different types of members. The invention also provides the option of a universal support member that is able to support different types of impact members or guide members. To this end the support members are provided with the same mounting system for fixing to the rotor and the support members are so constructed that when a different type of impact member or guide member is fitted the impact part of the impact surface or the guide surface (in particular the release end) of the impact member or guide member are in the same position with P T/NL02/00677

- 11 - respect to the rotor.

The invention provides the option of a stationary collision member that is located a greater distance away from the axis of rotation than the outer edge of the rotor that is provided with a stationary collision surface that is oriented essentially transversely to the straight path that the material describes when it is propelled outwards from the rotor following the impact with the impact member, viewed from a stationary standpoint, for causing the material that has collided once (co- rotating) to collide for a second time (stationary). The collision surface is formed by a material having a hardness equal to or greater than the hardness of the material that has collided once, it being possible for the collision surface to be formed by a metal and to be at least partially formed by hard metal or ceramic material. The invention furthermore provides the option that the collision surface is formed by an autogenous bed of own material. The stationary collision surface can essentially describe a surface of revolution, the axis of revolution of which is coincident with the axis of rotation but does not have to encircle the rotor completely and can even describe a relatively small segment.

To prevent or eliminate (cancel out) vibration that results from imbalance of the rotor the invention provides the option of a rotor construction that carries at least one annular balancing member, which balancing member is provided with a circular closed tube, the circle axis of which is coincident with the axis of rotation, which tube has an identical radial section all round, viewed from the direction of rotation, is at least partially filled with a fluid and contains at least three solid bodies that are able to move around freely in the tube, for reducing vibration of said rotor when this becomes unbalanced. The radial section of the tube can be made circular, but also square or rectangular. The solid bodies can have both different dimensions and different shapes. The solid body can describe a spherical shape or a disc shape. The shape of the solid bodies does not have to be identical and the dimensions of said solid bodies also do not have to be identical. The solid bodies can be made of a metal alloy, but also of a hard metal alloy or of ceramic material. The hollow balancing member is usually at least 75% filled with fluid, but can also be filled with a greater or smaller quantity of fluid, said fluid usually consisting of an oil-like substance, such that the solid bodies are not attacked or damaged or at least are attacked or damaged as little as possible. The balancing member does not have to be carried (directly) by said rotor but can also be carried by the shaft, which can be provided with a flange for this purpose.

BRTEF DESCRIPTION OF THE DRAWINGS

For better understanding, the aims, characteristics and advantages of the device of the invention which have been discussed, and other aims, characteristics and advantages of the device of the invention, are explained in the following detailed description of the device of the invention in relation to accompanying diagrammatic drawings. P T/NL02/00677

- 12 -

Figure 1 shows, diagrammatically, a plan view of the principle of the rotor according to the invention in a first embodiment, according to Figure 2.

Figure 2 shows, diagrammatically, a cross-sectional section A-A of the principle of the rotor according to the invention in a first embodiment according to Figure 1. Figure 3 shows, diagrammatically, the movement that the material describes on the rotor under the influence of centrifugal force.

Figure 4 shows, diagrammatically, a plan view of a second embodiment of the rotor according to the invention, according to Figure 5.

Figure 5 shows, diagrammatically, a cross-sectional section B-B of a second embodiment of the rotor according to the invention, according to Figure 4.

Figure 6 shows, diagrammatically, a plan view of a third embodiment of the rotor according to the invention, according to Figure 7.

Figure 7 shows, diagrammatically, a cross-sectional section C-C of a third embodiment of the rotor according to the invention, according to Figure 6. Figure 8 shows, diagrammatically, a plan view of a fourth embodiment of the rotor according to the invention, according to Figure 9.

Figure 9 shows, diagrammatically, a cross-sectional section D-D of a fourth embodiment of the rotor according to the invention, according to Figure 8.

Figure 10 shows, diagrammatically, a plan view of a fifth embodiment of the rotor according to the invention, according to Figure 11.

Figure 11 shows, diagrammatically, a cross-sectional section E-E of a fifth embodiment of the rotor according to the invention, according to Figure 10.

Figure 12 shows, diagrammatically, a plan view of a sixth embodiment of the rotor according to the invention, according to Figure 13. Figure 13 shows, diagrammatically, a cross-sectional section F-F of a sixth embodiment of the rotor according to the invention, according to Figure 12.

Figure 14 shows, diagrammatically, a plan view of a seventh embodiment of the rotor according to the invention, according to Figure 15.

Figure 15 shows, diagrammatically, a cross-sectional section G-G of a seventh embodiment of the rotor according to the invention, according to Figure 14.

Figure 16 shows, diagrammatically, an eighth embodiment of the rotor according to the invention.

Figure 17 shows, diagrammatically, a ninth embodiment of the rotor according to the invention.

Figure 18 shows, diagrammatically, a plan view of a tenth embodiment of the rotor according to the invention, according to Figure 19.

Figure 19 shows, diagrammatically, a cross-sectional section H-H of a tenth embodiment of the rotor according to the invention, according to Figure 18.

Figure 20 shows, diagrammatically, a plan view of an eleventh embodiment of the rotor according to the invention, according to Figure 21.

Figure 21 shows, diagrammatically, a cross-sectional section I-I of an eleventh embodiment of the rotor according to the invention, according to Figure 20.

Figure 22 shows, diagrammatically, a twelfth embodiment of the rotor according to the invention.

Figure 23, finally, shows, diagrammatically, a thirteenth embodiment of the rotor according to the invention. The drawings are not structural drawings but indicate diagrammatically - in sketch form - a number of possible embodiments and characteristics which are important or of essential importance for the description, the characterisation and the use of the rotor according to the invention. In the case of sections, shading is not always indicated and only the most important details are indicated by broken lines. Moreover, in sections only the components that are located on or close to these sections, i.e. of a section, are indicated and no items and members located further towards the rear.

BEST WAY OF IMPLEMENTING THE DEVICE OF THE INVENTION

A detailed reference to the preferred embodiments of the invention is given below. Examples thereof are shown in the appended drawings. Although the invention will be described together with the preferred embodiments, it must be clear that the embodiments described are not intended to restrict the invention to those specific embodiments. On the contrary, the intention of the invention is to comprise alternatives, modifications and equivalents which fit within the nature and scope of the invention as defined by appended claims. Figures 1 and 2 show, diagrammatically, the principle of the rotor (1) according to the invention in a first embodiment. The rotor (1) is of symmetrical construction and can be rotated (2) about a vertical axis of rotation (3) in at least one direction of rotation (both directions of rotation here) and here consists of two parts, a rotor blade (4) and a central part (5). The rotor (1) is provided on the top with a rotor surface (6) that is divided by said central part (5) into two parts, a rotor surface of the central part (central surface (7)) located at a high level and a rotor surface (peripheral surface (8)) of the rotor blade around it, located at a low level. The outer edges (9)(10) of, respectively, the central surface (7) and the peripheral surface (8) extend in a regular manner around the axis of rotation (3). Here both the central part (5) and the rotor blade (4) are of cylindrical construction, but the invention provides the option of other shapes. The rotor (1) is supported on a shaft (11), the shaft axis of which is coincident with the axis of rotation (3).

The central part (5) thus divides the rotor surface (6) into a central surface (7) and a peripheral 0677

- 14 - surface (8). The outer edge (10) of the rotor surface (6) is a greater radial distance away from the axis of rotation (3) than the outer edge (9) of the central surface (7). The peripheral surface (8) extends between the outer edge (9) of the central surface (7) and the outer edge (10) of the rotor surface (6) and is at a level below the outer edge (9) of the central surface (7). The central part (5) is provided with a step (an upright edge) (12) that extends between the outer edge (9) of the central surface (7) and the peripheral surface (8).

The rotor (1) is provided with a receiving and distributing member (13) that is carried by the rotor (1) in such a way that the receiving and distributing member (13) can be removed for replacement because of wear, which receiving and distributing member (13) is provided on the top with a receiving and distributing surface (14), the outer edge (15) of which extends in a regular manner around the axis of rotation (3) in such a way that the centre of the receiving and distributing surface (14) is coincident with the axis of rotation (3) and in such a way that the outer edge (10) of the rotor surface (6) is at least partially a greater radial distance away from the axis of rotation (3) than the outer edge (15) of the receiving and distributing surface (14), for receiving and distributing the material that is fed with the aid of a feed member (16) onto the rotor (1) at a location close to the axis of rotation (3). Here the receiving and distributing member (13) is constructed in an essentially square shape, by means of which there is a saving in weight and wear.

The rotor (1) is also provided with guide members (17), which here are carried by the rotor (1) with the aid of a support member (18), in such a way that the guide member (17) can be removed for replacement because of wear. The guide members (17) are some distance away from the axis of rotation (3) and are of mirror symmetrical construction with respect to the radial plane of symmetry (19) from the axis of rotation (3), in such a way that the guide member (17) functions in both directions of rotation (2). Here each guide member (17) is provided with two guide surfaces (20)(21) that extend in the direction of the outer edge (10) of the rotor (1). Each guide surface (20) is provided with a central feed (22) and a release end (23) and the outer edge (15) of the receiving and distributing surface (14) extends to beyond the central feed (22) and specifically does so in such a way that the outer edge (15) of the receiving and distributing surface (14) extends along the central feed (22) and, from the central feed (22), along at least part (24) of the guide surface (20) (here as far as approximately to the release end (23)) for, respectively, picking up the fed material from the receiving and distributing surface (14) by the central feed (22), guiding the picked-up material along the guide surface (20) under the influence of centrifugal force, after which the guided material is directed, when it leaves the guide member (17) at the location of the release end (23), into a spiral path (26) directed backwards, viewed in the direction of rotation (3) and viewed from a standpoint moving with the guide member (17), which spiral path (26) moves along a plane of movement (27) that is essentially coincident with or parallel to the plane of rotation (28).

The rotor (1) is also provided with an impact member (29) that is carried by the rotor (1) (here 0677

- 15 - with the aid of a removable support member (30)) in a position between the outer edge (15) of the receiving and distributing surface (14) arid the outer edge (10) of the rotor surface (6), in such a way that the impact member (29) can be removed for replacement because of wear. The impact member (29) is of mirror symmetrical construction with respect to the radial plane of symmetry (31), such that there is an impact part (32)(33) on either side of said plane of symmetry. The impact member (29) is provided with two impact surfaces (34)(35), each of which is associated with a guide surface (36)(37) of a guide member (17), such that at least one impact part (38) of the impact surface (34)(35) is oriented essentially transversely to the spiral path (26), viewed in the direction of rotation (3) and viewed from a standpoint moving with the impact member (29), to cause the material to collide, after which, when it leaves the impact member (29), the material that has collided once is directed into a straight path (39) directed forwards, viewed in the direction of rotation (3) and viewed from a stationary standpoint.

Furthermore, the impact surface, (34)(35) is of symmetrical construction with respect to the plane of rotation (28), such that the impact member (29) is reversible with respect to the plane of rotation (28), the upper impact part (38) being oriented essentially transversely to the spiral path (26), which here is coincident with the plane having thereon the outer edge (15) of the receiving and distributing member (13) (plane of rotation here). This makes it possible to reverse the impact member (29) - after the top half has worn out - with respect to the plane of rotation (28) having thereon the outer edge (15) of the receiving and distributing member (13), by means of which the life, i.e. tool life, of the impact member (29) is doubled. Here the difference in height between the peripheral surface (8) and the receiving and distributing member (13) is indicated as (X) and the portion of the impact surface (34)(35) that protrudes above the receiving and distributing surface (13) (plane of rotation) as (X'); thus, here X = X'.

The rotor (1) according to the invention is characterised in that at least that part of the rotor surface (6) that extends between the outer edge (15) of the receiving and distributing member (13) and the outer edge (10) of the rotor surface (peripheral surface) (6) is a greater distance away from the plane of movement (27) than the outer edge (15) of the receiving and distributing surface (14). The rotor is thus a stepped rotor. Because the axis of rotation (3) is oriented vertically here, it can also be stated that at least that part of the rotor surface (6) that extends between the outer edge (15) of the receiving and distributing member (14) and the outer edge (10) of the rotor surface (peripheral surface) (6) is at a level below the outer edge (15) of the receiving and distributing surface (14). With this arrangement it can also be stated that at least that part of the rotor surface (6) that extends between the outer edge (15) of the receiving and distributing member (14) and the outer edge (10) of the rotor surface (peripheral surface) (6) is a greater distance away from the feed member (16) than the outer edge (15) of the receiving and distributing surface (14).

Figure 3 shows, diagrammatically, the movement that the material describes on the rotor (25) 02 00677

- 16 - under the influence of centrifugal force. The impact member (40) is associated with a guide member (41) in such a way that the material that is directed into a spiral path (42) with the aid of the guide member (41) strikes the impact surface (43) of the impact member (40); and it continues to strike the impact member (40) when the impact surface (43) or guide member (41) starts to wear. Viewed from a standpoint moving with the rotor (25), the material on the receiving and distributing surface (44) moves outwards along a short spiral path (45) until it is picked up by the central feed (46) of the guide member (41). The material then moves along the guide surface (47) - during which movement it is accelerated under the influence of centrifugal force - and from the release end (48) is directed into a long spiral path (42) directed backwards. The impact surface (43) of the impact member (40) is arranged in a transverse position in this spiral path (42). The movements of the material along the long spiral path (42) and the movement of the impact member (40) about the axis of rotation (49) are essentially synchronised and the position of the impact member (40) is therefore determined by the angle of synchronisation (θ) between the radial line (50) from the axis of rotation (49) having the release end (48) thereon and the radial line (51) from the axis of rotation (49) having thereon the position where the material strikes the impact surface (43).

Figures 4 & 5 show, diagrammatically, a second embodiment of the rotor (53) according to the invention essentially the same as the first embodiment from Figures 1 and 2. Here the receiving and distributing member (54) is likewise of rectangular construction, the outer edge (55) of the receiving and distributing member (54) extending from the central feed (56) along part of the guide surface (57). The central part (58) is also of rectangular construction, such that the outer edge (59) of the central part (58) is coincident with the outer edge (55) of the receiving and distributing member (54). The rotor is similarly of rectangular construction, the impact members (60) being located at the corners (61) of the rectangle.

What is achieved by means of this construction is that the rotor surface (= peripheral surface) (62) and the outer edge (63) of the rotor (53) - which are subject to (intense) wear - are restricted to a minimum, whilst less structural material is required for the rotor (53), and the structural material can be better utilised with a rectangular shape than with a round shape.

Figures 6 and 7 show, diagrammatically, a third embodiment of the rotor (64) according to the invention. Here the rotor (64) consists of one part, is of symmetrical construction and here is provided with five sets of guide members (65) and impact members (66) associated with these. By this means the tool life is increased by 25% compared with a rotor constructed with four sets of associated accelerator members. The receiving and distributing member (67) is of pentagonal construction, so that here the amount of wear material is restricted as far as possible. The guide members (65) are provided with an annular plate (68) that is provided with a circular feed opening (69), the centre of which is coincident with the axis of rotation (70), which annular plate (68) is supported by the support member (71) of the guide member (65). What is achieved by this means is that the bottom edge (72) of the feed member (73) (feed tube) is much less subject to wear, whilst the material is better guided in the spiral path (74) towards impact member (66).

The invention provides the option that [I] the annular plate (68) can be removed individually,

[H] the guide members (65) can be removed together with the annular plate (68) and [IU] the guide members (65) can be removed together with the annular plate (68) and the receiving and distributing member (67). In the case of [H] and [uTJ for example as a cassette, optionally in the form of a wear part.

Figures 8 and 9 show, diagrammatically, a fourth embodiment of the rotor (75) according to the invention. This rotor (75) consists of one part and here also is of symmetrical construction and equipped with four symmetrical impact members (76) and four symmetrically associated guide members (77). The central part (78) is of cylindrical construction and forms a whole with the rotor blade (79). The receiving and distributing member (80) is constructed in a rectangular shape, the outer edge at the location of the guide members (77) extending from the central feed (81) along part of the guide surface (82) (here approximately as far as the release end (83)). The receiving and distributing member (80) is supported by the central part (78) with the aid of an adjusting plate (84), which makes it possible accurately to set or to adjust the height of the receiving and distributing surface (85) when the receiving and distributing surface (85) wears. The impact members (76) are of symmetrical V-shaped construction with the point (86) facing outwards and here are provided on the bottom (87) with a reinforcing plate (88) that has an appreciably greater tensile strength than the impact block section (89) to which the reinforcing plate (88) is firmly joined. The reinforcing plate (88) is provided with a hook construction (90) by means of which the impact member (76) is joined to the support member (91) that is located below the impact member (76). The impact member (76) anchors itself firmly with the aid of the centrifugal force. This form of construction has the advantage that [IJ the support member (91) cannot be damaged if the impact block (89) partially wears through, [HJ it is much easier to replace the impact member (76) and [DTJ a maximum amount of the wear material is consumed. It is easily possible to switch the rotor (75) over to another direction of rotation (92) at the point in time when one side wears through because the comminution intensity then drops off and a coarse, i.e. (partially) uncrushed, product is produced.

Figures 10 and 11 show, diagrammatically, a fifth embodiment of the rotor (93) according to the invention. The rotor (93) is likewise of symmetrical construction and the impact members (94) are reversible in the longitudinal direction (95), that is with respect to a plane (96) oriented transversely to the radial plane (97) from the axis of rotation (98), i.e. a plane that runs parallel to the axis of rotation (98). Here the elongated impact surface (99) that extends in the direction of the outer edge (100) of the rotor (93) is essentially provided with two impact parts (101)(102) located alongside one another, the impact part (102) that is furthest removed from the axis of rotation (98) being oriented transversely to the spiral path (103). After the impact part (102) has worn out, the impact member (94) is turned round, and the other impact part (101) is used.

Figures 12 and 13 show, diagrammatically, a sixth embodiment of the rotor (104) according to the invention. This rotor (104) consists of two parts, a rotor blade (105) and a central part (106), and is of non-symmetrical construction and is therefore operational in one direction of rotation (107). The four guide members (108) are oriented backwards viewed in the direction of rotation (107); here the release end (109) is behind the radial line (110) from the axis of rotation (111) having the central feed (112) thereon, viewed from the direction of rotation (107). The guide surface (113) is thus in the extension of the short spiral path (114) that the material describes on the receiving and distributing member (115) (see Figure 3), as a result of which this is very effective, that is makes a high capacity possible and limits the wear on the guide member (108). A non-symmetrical embodiment limits (halves) the tool life but gives much greater freedom in design. In the case of a symmetrical embodiment, there is far greater restriction in the choice of the radial distances to the impact member. A non-symmetrical rotor is therefore often extremely suitable for crushing less abrasive material.

Figures 14 to 15 show, diagrammatically, a seventh embodiment of the rotor (116) according to the invention. This rotor (116) consists of two parts, a rotor blade (117) and a central part (118), is of symmetrical construction and is provided with five sets of symmetrical impact members (119) (which are reversible with respect to the plane of rotation (120)) and five associated symmetrical guide members (121). The rotor (116) is provided with a second rotor blade (122) that is supported by the impact members (119) (support members (123) of the impact members (119)). The second rotor blade (122) is provided in the centre with an opening (124) for feeding the material onto the receiving and distributing member. This rotor construction (116) has the advantage that [I] the material is propelled outwards from the rotor (116) in an even more accurate manner and [JTJ no material is able to fly out upwards as can be the case with the open rotors. This makes it possible to produce an (even) more constant product with less oversize. On the other hand, the second rotor blade (122) is subject to (intense) wear along the underside (125) and must be provided with a protective covering (not indicated here) that has to be regularly replaced. The impact members (119) extend between the two rotor blades (117)(122) (peripheral surfaces), but the guide member (121) does not extend as far as the second rotor blade (122), as a result of which there is a saving in (wear) material.

Figure 16 shows, diagrammatically, an eighth embodiment of the rotor (126) according to the invention. This rotor (126) is essentially the same as the rotor (116) according to the seventh embodiment (Figures 15 and 16), rotates about a vertical axis (113), but the second rotor blade (127) here is also of stepped (128) construction; the part that extends beyond the guide member (129) is a greater distance away from the plane of rotation (130) than the central surface (131) of the second rotor blade (127). What is achieved by this means is that the wear along the top peripheral surface (132) is restricted or at least appreciably reduced. Such a rotor is also suitable for rotation about a horizontal axis (134), as is indicated in Figure 17 that shows, diagrammatically, a ninth embodiment of the rotor (135) according to the invention. In this context it is pointed out that the invention provides the option that essentially each of the forms of stepped rotor constructions discussed (and other conceivable forms of stepped rotor constructions) can rotate — as well as about a vertical axis - about an axis arranged non-vertically and (provided with a second rotor blade (137)) about a horizontal axis (134). For which purpose, of course, some modifications to the construction can be needed as far as the input (136) is concerned.

Figures 18 and 19 show, diagrammatically, a tenth embodiment of the rotor (138) according to the invention. The rotor (138) consists of two parts, a central part (139) and a rotor blade (140), and is of symmetrical construction and the symmetrical impact members (141) are constructed with autogenous impact surfaces (142)(143). To this end the impact member (141) is provided along the impact surface (142)(143) with a cavity (144) that (at least partially) extends in the direction of the outer edge (145) of the rotor (138), in such a way that own material (146) is able to deposit in this cavity (144) under the influence of centrifugal force. Here the cavity (144) is located between the central feed (147) and the release end (148) (i.e. tips). Such an autogenous impact member (141)(142)(143) has the advantage that much less wear occurs on the impact member (141); the impact intensity - and thus the comminution intensity - is, however, significantly lower. This can (partially) be eliminated by making the rotor (138) rotate more rapidly, as a result of which the material strikes the autogenous impact surface (142)(143) at higher velocity. Such an autogenous rotor (138) is extremely suitable for processing less hard material. Here the autogenous impact members (141) (cavities (144)) are provided with a cover plate

(149), as a result of which a bowl-shaped space is produced in which the material is better able to deposit.

Figures 20 and 21 show, diagrammatically, an eleventh embodiment of the rotor (150) according to the invention. The rotor (150) consists of one part, is of symmetrical construction and equipped with impact members (151) that are provided with a self-rotating impact surface (152). This makes it possible for the impact surface (152) to wear regularly all round, which makes it possible [I] to consume a maximum amount of the wear material, [H] appreciably to prolong the tool life, whilst [JH] the comminution intensity remains even more constant (more uniform) and, moreover, is higher (more intense) because the material is not impeded by an adjacent impact surface during crushing, when a cavity starts to form under the influence of wear, as is the case in the case of a non-moving (rotating) impact surface.

The stepped rotor construction (153) has the advantage that the rotating part can be arranged "free" above the rotor surface (154) (peripheral surface), so that there is less risk that material becomes trapped between (155) the rotor surface (154) and the bottom edge (156) of the rotating part and impedes rotation. Here the impact member (151) rotates (158) about a vertical axis (157). The invention provides the option that the self-rotation takes place "automatically" in that the centre of gravity shifts under the influence of wear, and provides the option that the self-rotation is enforced, that is to say is driven with the aid of, for example, an electric motor that is carried by the rotor (not shown here).

The invention furthermore provides the option that the guide members (159) are provided with a self-rotating guide surface (160), essentially similar to the self-rotating impact surface (152) (not indicated here). Self-rotation is possible both in symmetrical construction and in non-symmetrical construction.

Figure 22 shows, diagrammatically, a twelfth embodiment of the rotor (161) according to the invention that is constructed with both autogenous impact members (162) and autogenous guide members (163). This makes it possible to restrict the wear costs to a minimum, certainly if such a rotor is combined with an autogenous stationary impact member (not shown here).

Finally, Figure 23 shows, diagrammatically, a thirteenth embodiment of the rotor (164) according to the invention. Here the rotor (164) is of universal construction and can be provided with different types of guide members (here non-symmetrical (165), symmetrical (166), autogenous (167) and self-rotating (168)) and impact members (non-symmetrical (169), symmetrical (170), autogenous (171) and self-rotating (172)) which have been discussed above, but also other conceivable members can be installed.

To this end the invention provides the option that the support members for the guide members (165)(166)(167)(168) or impact members (169)(170)(171)(172) are removable and can be replaced by a support member that is able to support a different type of impact or guide member. On the other hand, the invention provides the option that the support member and the joint construction with the impact or guide member are to be made universal, such that at least two different impact and/or guide members can be installed (support members not indicated here).

Finally, the invention provides the option of a balancing member (172) that is indicated diagrammatically in Figures 1 and 2. To prevent or eliminate (cancel out) vibrations that result from imbalance of the rotor (1), the invention provides the option of a rotor construction that carries at least one annular balancing member (172), which balancing member (172) is provided with a circular closed tube (173), the circle axis of which is coincident with the axis of rotation (3), which tube (173) has an identical radial section all round, square in this case, viewed from the axis of rotation (3), is at least partially filled with a fluid and contains at least three solid bodies (174) which are able to move around freely in the tube (173), to reduce vibration of said rotor (1) when this becomes unbalanced. The radial section of the tube (173) can be made circular, but also square or rectangular. The solid bodies can have both different dimensions and different shapes. The solid body can describe a spherical shape or a disc shape. The shape of the solid bodies does not have to be the same and the dimensions of the solid bodies also do not have to be the same. The solid bodies can be made of a metal alloy, but also of a hard metal alloy or of ceramic material. The hollow balancing member is usually at least 75% filled with fluid, but can also be filled with a larger or smaller quantity of fluid, said fluid usually consisting of an oil-like substance, in such a way that the solid bodies are not attacked or damaged or at least are attacked or damaged as little as possible. The balancing member does not have to be carried (directly) by said rotor but can also be carried by the shaft which can be provided with a flange for this purpose.

The above descriptions of specific embodiments of the present invention have been given with a view to illustrative and descriptive purposes. They are not intended to be an exhaustive list or to restrict the invention to the precise forms given, and having due regard for the above explanation, many modifications and variations are, of course, possible. The embodiments have been selected and described in order to describe the principles of the invention and the practical application possibilities thereof in the best possible way in order thus to enable others skilled in the art to make use in an optimum manner of the invention and the diverse embodiments with the various modifications suitable for the specific intended use. The intention is that the scope of the invention is defined by the appended claims according to reading and interpretation in accordance with generally accepted legal principles, such as the principle of equivalents and the revision of components.

Claims

CLAΓMS

1. Device for causing a stream of granular material to collide, comprising:

- a rotor (1) that can be rotated about an axis of rotation (3) in at least one direction of rotation (2), which rotor (1) is provided with a central part (5) and on the top with a rotor surface (6), the outer edge (10) of which extends regularly around said axis of rotation (3), such that the centre of said rotor surface (6) is coincident with said axis of rotation (3), which rotor (1) is supported on a shaft (11), the shaft axis of which is coincident with said axis of rotation (3);

- a receiving and distributing member (13) that is carried by said central part (5) in such a way that said receiving and distributing member (13) can be removed for replacement because of wear, which receiving and distributing member (13) is provided on the top with a receiving and distributing surface (14), the outer edge (15) of which extends in a regular manner around said axis of rotation (3) in such a way that the midpoint of said receiving and distributing surface (14) is coincident with said axis of rotation (3) and in such a way that said outer edge (10) of said rotor surface (6) is at least partially a greater radial distance away from said axis of rotation (3) than is said outer edge (15) of said receiving and distributing surface (14), for receiving and distributing said material that is fed with the aid of a feed member (16) onto said rotor (1) at a location close to said axis of rotation (3);

- at least one guide member (17) that is carried by said rotor (1) in such a way that said guide member (17) can be removed for replacement because of wear, which guide member (17) is located some distance away from said axis of rotation (3) and is provided with at least one guide surface (20) that extends in the direction of the outer edge (10) of said rotor (1), which guide surface (20) is provided with a central feed (22) and a release end (23), the outer edge (15) of which receiving and distributing surface (14) at least extends as far as said release end (23), for, respectively, picking up said fed material from said receiving and distributing surface (14) by said central feed (22), guiding said picked-up material along said guide surface (20) under the influence of centrifugal force, after which said guided material is directed, when it leaves said guide member (17) at the location of said release end (23), into a spiral path (26) directed backwards, viewed in the direction of rotation (3) and viewed from a standpoint moving with said guide member (17), said material moving between said guide member (17) and an impact member (29) along a plane of movement (27) that is essentially coincident with the plane of rotation (3);

- at least one impact member (29) that is carried by said rotor (1) at a location between the outer edge (15) of said receiving and distributing surface (14) and the outer edge (10) of said rotor surface (6), in such a way that said impact member (29) can be removed for replacement because of wear, which impact member (29) is provided with an impact surface (34) that is associated with said guide member (17), in such a way that at least one impact part (38) of said impact surface (34) is oriented essentially transversely to said spiral path (26), viewed in the direction of rotation (3) and viewed from a standpoint moving with said impact member (29) for causing said material to collide, after which, when it leaves said impact member (29), said material that has collided once is directed into a straight path (39) directed forwards, viewed in the direction of rotation (3) and viewed from a stationary standpoint; - characterised in that

- at least that part of said rotor surface (6) that extends between said outer edge (9) of said central part (5) and the outer edge (10) of said rotor surface (6) is located a greater distance away from said plane of movement (27) than said outer edge (9) of said central part (5).

2. Device according to Claim 1, wherein said axis of rotation is oriented vertically and at least that part of said rotor surface that extends between said outer edge of said central part and the outer edge of said rotor surface is at a level below said outer edge of said central part.

3. Device according to Claim 1, wherein at least that part of said rotor surface that extends between said outer edge of said central part and the outer edge of said rotor surface is a greater distance away from said feed member than said outer edge of said cenfral part.

4. Device according to Claim 1, wherein said outer edge of said rotor surface is, all round, a greater radial distance away from said axis of rotation than said outer edge of said central part.

5. Device according to Claim 1, wherein said central part is provided with a step that extends between said outer edge of said central part and said rotor surface.

6. Device according to Claim 1, wherein said outer edge of said receiving and distributing surface extends along said central feed and, from said central feed, along at least part of said guide surface.

7. Device according to Claim 1, wherein the radius of the circle that said outer edge of said receiving and distributing surface describes is greater than the radial distance from said axis of rotation to said central feed.

8. Device according to Claim 1, wherein the radius of the circle that said outer edge of said receiving and distributing surface describes is less than the radial distance from said axis of rotation to said release end.

9. Device according to Claim 1, wherein said rotor is provided with a central part that divides said rotor surface into a central surface and a peripheral surface, the outer edge of which central surface extends in a regular manner around said axis of rotation, such that the centre of said central surface is coincident with said axis of rotation, the outer edge of which rotor surface is at least partially a greater radial distance away from said axis of rotation than the outer edge of said central part, which peripheral surface, which extends between said outer edge of said central surface and the outer edge of said rotor surface, is at a level below said outer edge of said central surface, which central part is provided with a step that extends between said outer edge of said central surface and said peripheral surface, with the aid of which central part said receiving and distributing member is carried by said rotor.

10. Device according to Claim 9, wherein said central part forms part of said rotor such that said central part and said rotor constitute a whole.

11. Device according to Claim 9, wherein said central part constitutes a separate part.

12. Device according to Claim 11, wherein said separate central part is firmly fixed to said rotor.

13. Device according to Claim 12, wherein said separate cenfral part is firmly bolted to said rotor.

14. Device according to Claim 9, wherein said central surface describes a circular shape.

15. Device according to Claim 9, wherein said cenfral surface describes a regular polygonal shape and said rotor is provided with a guide member at a location close to each of the corners of said polygon.

16. Device according to Claim 9, wherein said outer edge of said central surface describes an essentially square shape and said rotor is provided with four guide members that are arranged at a location close to the corners of said square-shaped central surface.

17. Device according to Claim 9, wherein said central surface describes an elongated shape and said rotor is provided with two guide members that are arranged at a location close to the ends of said central surface of elongated shape.

18. Device according to Claim 9, wherein said receiving and distributing surface describes essentially the same shape as said central surface.

19. Device according to Claim 1, wherein said outer edge of said rotor surface essentially describes a square shape and said rotor is provided with four impact members that are arranged at a location close to the corners of said square-shaped rotor surface.

20. Device according to Claim 1, wherein said rotor surface describes an elongated shape and said rotor is provided with two impact members that are arranged at a location close to the ends of said rotor surface of elongated shape.

21. Device according to Claim 1, wherein said receiving and distributing member is carried with the aid of an adjusting plate in such a way that the height of said receiving and distributing surface is adjustable along said axis of rotation by means of the choice of the thickness of said adjusting plate.

22. Device according to Claim 9, wherein said guide member is carried by said central part.

23. Device according to Claim 1, wherein said guide member is carried by said receiving and distributing member.

24. Device according to Claim 1, wherein said impact member is carried by said rotor with the aid of a support member.

25. Device according to Claim 1, wherein said guide member is carried by said rotor with the aid of a support member.

26. Device according to one of Claims 24 and 25, wherein said support member can be removed for replacement because of wear.

27. Device according to one of Claims 24 and 25, wherein said support member can be removed for replacement by a different type of support member, suitable for supporting a different type of impact member or guide member.

28. Device according to one of Claims 24 and 25, wherein at least two different types of impact members or guide members can be supported by said support member.

29. Device according to Claim 9, wherein said support member for said guide member is a greater radial distance away from said axis of rotation than the outer edge of said central surface.

30. Device according to Claim 1, wherein said guide member is mirror symmetrical with respect to the radial plane of symmetry from said axis of rotation, such that said guide member functions in both directions of rotation.

31. Device according to Claim 1, wherein said impact member is of mirror symmetrical construction with respect to a plane of symmetry, such that said impact surface, which essentially is of sfraight construction, is provided with an impact part on either side of said plane of symmetry.

32. Device according to Claim 31, wherein said plane of symmetry runs parallel to the plane of rotation, such that said impact member is reversible with respect to said rotational plane of symmetry, the distance between said outer edge of said receiving and distributing surface and said outer edge of said peripheral surface being chosen to be sufficiently large that said impact part that is furthest removed from said peripheral surface is oriented essentially transversely to said spiral path.

33. Device according to Claim 31, wherein said plane of symmetry is coincident with a plane that is oriented transversely to the radial plane from said axis of rotation, such that said impact member is reversible with respect to said radial plane of symmetry, said impact part that is furthest removed from said axis of rotation being oriented essentially transversely to said spiral path.

34. Device according to Claim 1, wherein said impact member is mirror symmetrical with respect to the radial plane of symmetry from said axis of rotation, such that said impact member functions in both directions of rotation.

35. Device according to Claim 1, wherein said impact member is provided with a self-rotating impact surface that essentially describes a surface of revolution, the axis of revolution of which runs essentially parallel to said axis of rotation and is coincident with the axis of rotation of said self- rotating impact surface.

36. Device according to Claim 1, wherein the distance between said outer edge of said receiving and distributing surface and said rotor surface is at least 25 mm.

37. Device according to Claim 1, wherein the distance between said outer edge of said receiving and distributing surface and said rotor surface is at least 50 mm.

38. Device according to Claim 1 , wherein the distance between said outer edge of said receiving and distributing surface and said rotor surface is at least 100 mm.

39. Device according to Claim 1, wherein the distance between said outer edge of said receiving and distributing surface and said rotor surface is at least 200 mm.

40. Device according to Claim 1, wherein said receiving and distributing member can be removed together with said guide member.

41. Device according to Claim 1, wherein said rotor is provided with an annular plate, the outer edge of which extends in a regular manner around said axis of rotation and is at a level above said receiving and distributing surface, which annular plate is provided with a circular feed opening, the centre of which is coincident with said axis of rotation, which annular plate is supported by said guide member.

42. Device according to Claim 41, wherein said guide member can be removed together with said annular plate.

43. Device according to Claim 41, wherein said guide member can be removed together with said annular plate and said receiving and distributing member.

44. Device according to Claim 1, wherein said rotor is equipped with more than one guide member, each of which is provided with a support member, which support members are joined to one another along the top with the aid of an annular member that extends in a regular manner around said axis of rotation, such that the centre of said annular member is coincident with said axis of rotation.

45. Device according to Claim 44, wherein said annular member is provided with a wear- resistant annular wall to protect said annular member from wear, which annular wall consists of at least one piece and can be removed and is so constructed that said annular wall anchors itself against said annular member under the influence of centrifugal force.

46. Device according to Claim 1, wherein said rotor is provided with a first rotor blade and a second rotor blade, which first rotor blade is supported on said shaft and carries said receiving and distributing surface, which second rotor blade is located some distance away from said first rotor blade, parallel to said first rotor blade, is carried by said first rotor blade and is provided with a circular feed opening, the circle centre of which is coincident with said axis of rotation for feeding said material onto said receiving and distributing surface, which first rotor blade is provided on the top with a first rotor surface and which second rotor blade is provided on the bottom with a second rotor surface.

47. Device according to Claim 46, wherein the outer edge of said second rotor surface describes a peripheral shape that is essentially the same as the peripheral shape of said second rotor surface.

48. Device according to Claim 47, wherein said second rotor blade is provided on the side oriented towards said first rotor blade with a second step that divides said second rotor blade into a second central surface, that extends between said outer edge of said feed opening and said second step, and a second peripheral surface, that extends between said second step and the outer edge of said second rotor surface, such that said second peripheral surface is at a level that is further removed from said first rotor blade than said outer edge of said second central surface.

49. Device according to Claim 1, wherein said impact part is located a greater radial distance away from said axis of rotation than said release end and behind the radial line from said axis of rotation having said release end thereon.

50. Device according to Claim 1, wherein the position of said impact part is determined by the angle (θ) between the radial line having said release end thereon and the radial line having thereon the location where said spiral path and the path that said impact part describes intersect one another, to be so selected that the arrival of said material moving along said spiral path at said location where said paths intersect one another is synchronised with the arrival of said impact part at said location.

51. Device according to Claim 1, wherein said impact member is provided with a metal impact surface.

52. Device according to Claim 1, wherein said impact member is at least partially formed by hard metal.

53. Device according to Claim 1, wherein said impact member is at least partially formed by ceramic material.

54. Device according to Claim 1, wherein said impact surface is at least partially formed by an autogenous bed of own material.

55. Device according to Claim 1, wherein said guide member is provided with a self-rotating guide surface.

56. Device according to Claim 1, wherein said guide surface is made of metal.

57. Device according to Claim 1, wherein said guide surface at least partially consists of hard metal.

58. Device according to Claim 1, wherein said central feed is at least partially made of hard metal.

59. Device according to Claim 1, wherein said central feed is at least partially made of ceramic material.

60. Device according to Claim 1, wherein said release end is at least partially made of hard metal.

61. Device according to Claim 1, wherein said release end is at least partially made of ceramic material.

62. Device according to Claim 1, wherein said guide surface is at least partially formed by an autogenous bed of own material.

63. Device according to one of Claims 35 and 55, wherein the self-rotation is generated under the influence of centrifugal force.

64. Device according to one of Claims 35 and 55, wherein the self-rotation is forcibly generated with the aid of a drive mechanism.

65. Device according to Claim 1, wherein said impact member or the guide member is carried by said rotor with the aid of a support member.

66. Device according to Claim 65, wherein said support member can be removed for replacement because of wear or damage.

67. Device according to Claim 65, wherein said support member can be removed for replacement by a different type of support member, for supporting a different type of impact or support member.

68. Device according to Claim 65, wherein said support member is able to support several types of impact members or guide members.

69. Device according to Claim 1, wherein said receiving and distributing surface is made of metal.

70. Device according to Claim 1, wherein said receiving and distributing member is at least partially made of hard metal.

71. Device according to Claim 1, wherein said receiving and distributing member is at least partially made of ceramic material.

72. Device according to Claim 1, wherein said receiving and distributing surface is at least partially formed by an autogenous bed of own material.

73. Device according to Claim 1, wherein that part of said rotor surface that extends between the outer edge of said receiving and distributing member and the outer edge of said rotor is at least partially formed by an autogenous bed of own material.

74. Device according to Claim 1, wherein that part of said rotor surface that extends between the outer edge of said receiving and distributing member and the outer edge of said rotor is at least partially formed by hard metal.

75. Device according to Claim 1, wherein that part of said rotor surface that extends between the outer edge of said receiving and distributing member and the outer edge of said rotor is at least partially formed by ceramic material.

76. Device according to Claim 1, wherein at least one stationary collision member is provided with a stationary collision surface that is oriented essentially transversely to said straight path, viewed from a stationary standpoint, for causing said material that has collided once to collide for a second time.

77. Device according to Claim 76, wherein said collision surface is formed by a material having a hardness equal to or greater than the hardness of said material that has collided once.

78. Device according to Claim 77, wherein said collision surface is formed by a metal.

79. Device according to Claim 77, wherein said collision surface is at least partially formed by hard metal.

80. Device according to Claim 77, wherein said collision surface is at least partially formed by ceramic material.

81. Device according to Claim 77, wherein said collision surface is formed by an autogenous bed of own material.

82. Device according to one of Claims 1 to 81, wherein hard metal is understood to be an alloy of at least one hard, wear-resistant constituent in the from of tungsten carbide or titanium carbide and at least one soft metal constituent in the form of cobalt, iron or nickel.

83. Device according to one of Claims 1 to 81, wherein ceramic material is understood to be a material that at least partially consists of aluminium oxide (AI2O3).

84. Device according to one of Claims 1 to 81, wherein ceramic material is understood to be a material that at least partially consists of silicon oxide (SiO₂).

85. Device according to Claim 76, wherein said stationary collision surface describes a surface of revolution, the axis of revolution of which is coincident with said axis of rotation.

86. Device according to Claim 1, wherein said rotor construction carries at least one annular balancing member, which balancing member is provided with a circular closed tube, the circle axis of which is coincident with said axis of rotation, which tube has an identical radial section all round, viewed from said axis of rotation, is at least partially filled with a fluid and contains at least three solid bodies that are able to move around freely in said tube, for reducing vibration of said rotor when this becomes unbalanced.

87. Device according to Claim 86, wherein the radial section of said tube is made circular.

88. Device according to Claim 86, wherein the radial section of said tube is made square.

89. Device according to Claim 86, wherein the radial section of said tube is made rectangular.

90. Device according to Claim 86, wherein said solid body does not describes a spherical shape.

91. Device according to Claim 86, wherein said solid body describes a disc shape.

92. Device according to Claim 86, wherein the shape of said solid bodies is not identical.

93. Device according to Claim 86, wherein the dimensions of said solid bodies are not identical.

94. Device according to Claim 86, wherein said solid body is made of a metal alloy.

95. Device according to Claim 86, wherein said solid body is made of a hard metal alloy.

96. Device according to Claim 86, wherein said solid body is made of a ceramic material.

97. Device according to Claim 86, wherein said hollow balancing member is at least 75% filled with fluid.

98. Device according to Claim 86, wherein said fluid consists of an oil-like substance.

99. Device according to Claim 86, wherein said balancing member is not carried by said rotor.

100. Device according to Claim 99, wherein said shaft is provided with a flange, which flange carries said balancing member.