WO2003035261A1

WO2003035261A1 - Symmetrical guide member

Info

Publication number: WO2003035261A1
Application number: PCT/NL2002/000676
Authority: WO
Inventors: Johannes Petrus Andreas Josephus Zanden Van Der
Original assignee: Zanden Van Der, 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 a vertical axis of rotation, which rotor is provided with at least one guide member and at least one impact member, the take-off location of which guide member is displaced, when wear occurs along the guide surface, in such a way that the material is directed from a said displaced take-off location into a spiral path that is oriented essentially transversely or remains oriented essentially transversely to the impact surface of the impact member that is associated with the guide member.

Description

SYMMETRICAL GUIDE MEMBER

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 lαiown 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 in the direction of 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, is 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 impact 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 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 and is of particular importance with regard to the invention. The known symmetrical rotor is provided with guide members which are symmetrical with respect to a radial plane from the axis of rotation of said rotor, each of which symmetrical guide member is provided with two guide surfaces, one for each direction of rotation, and each guide surface is associated with the impact surface of a co- rotating impact member.

The material that is fed onto the receiving and distributing member of the rotor is picked up from said receiving and distributing member by the central feed of the guide surface, accelerated along the guide surface under the influence of centrifugal force and, from the release end of the guide surface, is directed into a spiral path directed backwards, viewed from a standpoint moving with said guide member. The function of the guide member, which is carried by said rotor, is thus to bring the material into a spiral path directed backwards in such a way that the material strikes the impact member that is also carried by said rotor. To this end the impact surface of the impact member is arranged transversely (essentially synchronously) in the spiral path, there being said to be an impact member that is associated with the guide member. In the case of a mirror symmetrical guide member - that is provided with two guide surfaces - each of these guide surfaces is associated with an impact surface of an impact member. It is possible for the impact member also to be of symmetrical construction - thus also having two impact surfaces - each of which is associated with a guide surface (preferably of a mirror symmetrical guide member).

As has been stated, the known symmetrical guide member has the advantage that the rotor is operational in both directions. As a result the tool life is doubled and the wear material is used more effectively, whilst, as a result of the simple mounting, where use can be made of centrifugal force, the guide members can be replaced very easily and do not (necessarily) have to be secured. However, the known symmetrical guide members also have disadvantages. For instance, the location (release end) where the material leaves the guide member and is guided into the spiral path shifts gradually as wear occurs along the guide surface. This shift can be fairly large and takes place inwards, i.e. in the direction of the radial plane of symmetry. The consequence of this is that the spiral path along which the material moves is also displaced inwards or curves away more towards the inside, that is in the direction of the axis of rotation, and the result of this, in turn, is that the strike location where the material strikes the impact surface of the co-rotating impact member also moves, viewed from a standpoint moving with said guide member. Because not only the release end wears but the central feed and the guide surface also wear, it is possible that the guide surface acquires such a (worn) shape that the spiral path no longer moves outwards (that is away from the axis of rotation). However, it is in particular the position or shifted position of the central feed that determines the location of the spiral path; the influence of the wear along the guide surface or central feed is in general less but, as has been stated, can have a significant influence. Even if the co-rotating impact surface is arranged a short distance away from the release end there can be an inward shift ofthe strike location. In the majority of cases, however, there is an inward displacement ofthe spiral path, that is in the direction ofthe outer edge ofthe rotor. As wear occurs along the guide surface the material can start to strike the impact surface against the edge of the impact surface and even start to move past the impact surface in front or behind (on the inside or outside viewed from the axis of rotation). Such a shift in the spiral movement can therefore result in the probability of breakage decreasing as the impact surface starts to wear. Assuming an outward shift of the spiral path, it is possible to provide the impact surface with a strike surface that is continued a little towards the outside (in the direction of the axis of rotation). What is achieved by this means is that the material continues to strike the impact member, i.e. the impact surface, (for longer) when the spiral path moves (outwards) as a result of wear. However, the velocity at which the material strikes the impact surface increases progressively as the strike location becomes a greater radial distance away from the axis of rotation; the probability of breakage increases as a result and a finer product is obtained. Furthermore, the guide member and the impact member often wear at very different rates, as a result of which the guide member has to be replaced only after several impact members have been replaced. In order nevertheless to obtain a constant product it is then necessary to reduce the rotational velocity of the rotor. It is true that this saves additional energy, but the drive (electric motor) has to be provided with a (very expensive) frequency control for this purpose.

ATM OF THE INVENTION

The aim of the invention is, therefore, to provide an impact member as described above that does not have these disadvantages, or at least displays these to a lesser extent. Said aim is achieved with the aid of a guide member with which, when wear occurs along the guide surface, the take-off location is displaced in such a way that the material is guided from said displaced take-off location into a spiral path that is oriented essentially transversely or remains oriented transversely to the impact part, i.e. strike location, of the impact surface of the impact member that is associated with said guide member. To this end the invention provides a device for causing a stream of granular material to collide, comprising:

- a rotor that can be rotated about a vertical axis of rotation in both directions of rotation, which rotor consists of at least one part and is supported on a shaft;

- a receiving and distributing member that is carried by the rotor and is provided with a receiving and distributing surface, the outer edge of which extends in a regular manner around the axis of rotation, 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 with the aid of a support member in such a way that the guide member can be removed for replacement because of wear, which guide member is some distance away from the axis of rotation, which guide member is mirror symmetrical with respect to the radial plane of symmetry from the axis of rotation, which radial plane of symmetry divides the peripheral surface of the guide member into two identical side surfaces, each of which side surfaces extends in the direction of the outer edge of the rotor and is provided with a central feed, a guide surface and a release end for, respectively, picking up at least a portion of the fed material by the central feed, guiding the material picked up along the guide surface under the influence of centrifugal force, after which, when it leaves the guide member at the location of the release end, the guided material is directed into a spiral path directed backwards, viewed in the direction of rotation and viewed from a standpoint moving with the guide member; - at least one impact member that is carried by the rotor and is provided with at least one impact surface that is associated with the guide surface, 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; - the side surface being provided with an extended side surface section that extends from the release end further in the direction of the outer edge of the rotor as far as the outside end of the extended side surface section, which extended side surface section is located behind the radial line from the axis of rotation with the release end thereon, viewed in the direction of rotation, which outer end is located a greater radial distance away from the axis of rotation than the release end and a smaller radial distance away from the axis of rotation than the impact surface.

It is preferable that the extended side surface section is located behind the straight line with the release end thereon, which straight line is parallel to the radial plane of symmetry.

What is achieved by this means is that, as wear occurs along the guide surface, the release end not only moves inwards, that is in the direction of the radial plane of symmetry, but at the same time also gradually moves outwards, essentially along said extended side surface section, with the consequence that the spiral path does not move inwards - or at least moves inwards to a much lesser extent - so that the material continues to strike the impact surface on virtually the same impact part.

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.

It is important that the outer end is a smaller radial distance away from the axis of rotation than the spiral path, viewed along the radial line from the axis of rotation having the outer end thereon, because otherwise the path is disturbed.

The invention provides the option that the shape of the extended side surface section can be so chosen that when wear occurs on the guide surface and, as a consequence, the release end moves outwards along the extended side surface section in the direction of the outer end and inwards in the direction ofthe radial plane of symmetry with the result that the material leaves the guide member at a take-off location along the extended side surface section, the material then moves along a displaced spiral path having thereon the impact surface or the impact part (i.e. strike location), viewed from a standpoint moving with the guide member.

It is important with this arrangement that the outer end is located a smaller radial distance away from the axis of rotation than the displaced spiral path, viewed along the radial line from the axis of rotation having the outer end thereon.

As far as the shape ofthe guide member is concerned, the invention provides the option that: - the release end is located a greater distance away from the radial plane of symmetry than the central feed, the extended side surface section being located behind the straight line having the release end thereon, which straight line is parallel to the radial plane of symmetry, viewed in the direction of rotation;

- the release end is located the same distance away from the radial plane of symmetry as the central feed, the extended side surface section being located behind the straight line having thereon the central feed and the release end, viewed in the direction of rotation;

- the release end is located a smaller distance away from the radial plane of symmetry than the central feed, the extended side surface section being located behind the straight line having thereon the central feed and the release end, viewed in the direction of rotation. Because the shape of the guide member (and the central feed) - and the shape that the guide member assumes under the influence of wear - has an influence on whether the location of the spiral path can shift, many embodiments ofthe guide member are conceivable or possible. The invention therefore provides, inter alia, the options:

- that the difference between the radial distance from the axis of rotation to the release end and the corresponding radial distance to the central feed is, respectively, equal to or greater or smaller than the difference between the radial distance from the axis of rotation to the outer end and the corresponding radial distance to the release end;

- that the guide surface extends in the direction of the outer edge of the rotor along, respectively, a straight surface, along a convex surface viewed from said radial plane of symmetry, it being possible for said convex surface to describe an arc, or along a concave surface viewed from said radial plane of symmetry;

- that the extended side surface section extends in the direction of the outer edge ofthe rotor, respectively, along a straight surface, along a convex surface viewed from said radial plane of symmetry, it being possible for the convex surface to describe an arc, or along a concave surface viewed from said radial plane of symmetry; - that at the location of the central feed the side surface is oriented transversely to the radial plane of symmetry or that at the location of the central feed the side surface is oriented essentially perpendicularly to the radial plane of symmetry and at the location of the release end the side surface is essentially parallel to the radial plane of symmetry or at the location of the outer end is oriented transversely to the radial plane of symmetry or at the location ofthe outer end is oriented essentially perpendicularly to the radial plane of symmetry;

The invention provides the option that the guide member is reversible with respect to the radial plane of symmetry or is reversible with respect to the plane of rotation.

A further (supplementary) option is the "delay" of wear, such that the spiral path displaces less rapidly. This can be achieved by, for example, making the release end of a material having a greater wear resistance.

To this end the invention provides, inter alia, the options:

- that, respectively, the receiving and distributing member, guide surface, the central feed, the release end and/or the extended side surface section is/are at least partially made of a hard metal;

- that, respectively, the guide surface, the central feed, the release end and/or the extended side surface section is/are at least partially made of a ceramic material.

Here 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 receiving and distributing member is also subject to wear and therefore has to be constructed with as small a diameter (circumference) as possible, but must be effective such that the material is fed to the central feed in a regular manner.

To this end the invention provides the option that the outer edge of the receiving and distributing surface extends at least as far as the central feed or (preferably) extends along the central feed and at least part ofthe guide surface.

To prevent or eliminate (cancel out) vibrations that result 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, and is at least partially filled with a fluid and contains at least three solid bodies which are able to move around freely in the tube, for reducing vibration of said rotor when this becomes unbalanced. The radial section ofthe 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 larger 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.

BRIEF 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. Figure 1 shows, diagrammatically, a plan view of a rotor to which the guide member according to the invention relates, according to Figure 2.

Figure 2 shows, diagrammatically, a cross-sectional section A-A of a rotor to which the guide member according to the invention relates, Figure 1.

Figure 3 shows, diagrammatically, the short and long spiral movement. Figure 4 shows a first diagrammatic rotor with velocity components.

Figure 5 shows the development ofthe velocity components according to Figure 4. Figure 6 shows a second diagrammatic rotor with velocity components.

Figure 7 shows the development ofthe velocity components according to Figure 6.

Figure 8 shows a third diagrammatic rotor with velocity components.

Figure 9 shows the development ofthe velocity components according to Figure 8. Figure 10 shows a fourth diagrammatic rotor.

Figure 11 shows the development ofthe velocity components according to Figure 10.

Figure 12 shows the fourth diagrammatic rotor from Figure 10 with various cylinder diameters.

Figure 13 shows, diagrammatically, a rotor with guide members oriented backwards. Figure 14 shows, diagrammatically, a rotor with guide members oriented radially.

Figure 15 shows, diagrammatically, a rotor with guide members oriented forwards.

Figure 16 shows, diagrammatically, a rotor with cylindrical guide members.

Figure 17 shows, diagrammatically, the influence that wear of the guide member has on the location ofthe spiral path. Figure 18 shows, diagrammatically, a first embodiment of a guide member according to the invention.

Figure 19 shows, diagrammatically, a second embodiment ofthe guide member according to the invention.

Figure 20 shows, diagrammatically, a third embodiment of the guide member according to the invention.

Figure 21 shows, diagrammatically, a fourth embodiment of the guide member according to the invention.

Figure 22 shows, diagrammatically, a fifth embodiment of the guide member according to the invention. Figure 23 shows, diagrammatically, a sixth embodiment of the guide member according to the invention.

Figure 24 shows, diagrammatically, a seventh embodiment ofthe guide member according to the invention.

Figure 25 shows, diagrammatically, an eighth embodiment ofthe guide member according to the invention.

Figure 26 shows, diagrammatically, a plan view B-B of a first embodiment of a support member, according to Figure 27.

Figure 27 shows, diagrammatically, a side view C-C of a first embodiment of a support member, according to Figure 26. Figure 28 shows, diagrammatically, a plan view D-D of a second embodiment of a support member, according to Figure 29. Figure 29 shows, diagrammatically, a side view E-E of a second embodiment of a support member, according to Figure 28.

Figure 30 shows, diagrammatically, a plan view F-F of a third embodiment of a support member, according to Figure 31. Figure 31 shows, diagrammatically, a side view of a third embodiment of a support member, according to Figure 28.

Figure 32 shows, diagrammatically, a plan view of a rotor according to Figure 33.

Figure 33 shows, diagrammatically, a cross-sectional section H-H ofthe plan view in Figure 32. Figure 34 shows, diagrammatically, a guide member that is provided with an attachment.

The drawings are not structural drawings but indicate diagrammatically - in sketch form - a number of possible embodiments and characteristics that are important or of essential importance for the description, the characterisation and the use of the guide member according to the invention. In the case of sections, shadings are not always indicated and only the most important details are indicated by broken lines. Moreover, in sections only the components which are located on or close to the sections, i.e. of a section, are indicated and no articles 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 the scope ofthe invention as defined by appended claims.

Figures 1 and 2 show, diagrammatically, in the general sense a rotor (1) to which the guide member (2) according to the invention relates. The invention relates to a rotor (1) that is provided with guide members (2) and impact members (3) associated therewith. In the general sense it relates to a symmetrical rotor that can be rotated about a vertical axis of rotation (4) in both directions of rotation (203), which rotor (1) here consists of one part (5) (but can also consist of several parts) and is supported on a shaft (6). The rotor (1) is provided with a receiving and distributing member (7) that is carried by the rotor (1) and is provided with a receiving and distributing surface (8), the outer edge (9) of which extends in a regular manner around the axis of rotation (4), for receiving and distributing the material that is fed with the aid of a feed member (not shown here) onto the rotor (1) at a location close to the axis of rotation (4). The rotor (1) is furthermore provided with four guide members (2) which here are each carried by the rotor (1) with the aid of a support member (10), in such a way that the guide member (2) can be removed for replacement because of wear, which guide member (2) is located some distance away from the axis of rotation (4), which guide member (2) is mirror symmetrical with respect to the radial plane of symmetry (11) from the axis of rotation (4), which radial plane of symmetry (11) divides the peripheral surface of said guide member (2) into two identical side surfaces (13)(14), which side surface (13) extends in the direction of the outer edge (15) of the rotor (1) and is provided with a central feed (16), a guide surface (17) and a release end (18), for, respectively, picking up at least a portion of the fed material by the central feed (16), guiding the picked-up material along the guide surface (17) under the influence of centrifugal force, after which, when it leaves the guide member (2) at the location of the release end (18), the guided material is directed into a spiral path (19) directed backwards, viewed in the direction of rotation (203) and viewed from a standpoint moving with the guide member (2), the release end (18) of which side surface (13) is here the greatest distance away from the radial plane of symmetry (11). The rotor (1) is also provided with four symmetrical impact members (3) that are carried by the rotor (1), and are each provided with two impact parts (20)(21) that are each provided with an impact surface (22)(23) that are each associated with a guide surface (24)(25), such that at least one impact part of the impact surface (22)(23) is oriented essentially transversely to the spiral path (19), viewed in the direction of rotation and viewed from a standpoint moving with the impact member (3), for causing said material to collide. When the material leaves the impact member (3) it is propelled outwards from the rotor (1) at high velocity and directed into a straight path (26).

Figure 3 shows, diagrammatically, the movement that the material describes on the rotor (27) under the influence of centrifugal force. The impact member (28) is associated with the guide member (29) in such a way that the material that is directed into a spiral path (30) with the aid of the guide member (29) strikes the impact surface (31) of the impact member (28); and it continues to strike the impact member (28) when the guide member (29) starts to wear.

Viewed from a standpoint moving with the rotor (27), the material on the receiving and distributing surface (32) moves outwards along a short spiral path (33) until it is picked up by the central feed (34) ofthe guide member (29). The material then moves along the guide surface (35) - during which movement it is accelerated under the influence of centrifugal force - and from the release end (36) is directed into a long spiral path (30) directed backwards. The impact surface (31) of the impact member (28) is arranged in a location transversely in this long spiral path (30). The movements ofthe material along the spiral path (30) and the movement ofthe impact member (28) around the axis of rotation (37) are essentially synchronised and the position of the impact member (28) is therefore determined by the synchronisation angle (θ) between the radial line (38) from the axis of rotation (37) with the release end (36) thereon and the radial line (40) from the axis of rotation (38) having thereon the location (41) where the material strikes the impact surface (31).

Figure 4 shows a first diagrammatic rotor (42) that rotates at a rotational velocity (Ω) around an axis of rotation (43), which rotor (42) is provided with a central surface (44) that acts as feed location, and a guide member (45) that is provided with a central feed (46), a guide surface (47) and a release end (48). The material is picked up by the central feed (46) and then accelerated along the guide surface (47), which here is oriented forwards, viewed in the direction of rotation (49), under the influence of centrifugal force, the material building up a radial (Vr) and a transverse (Vt) velocity component. The accelerated material is then propelled outwards from said release end (48) at an absolute take-off velocity (Vabs) along a straight path (50) directed forwards, viewed in the direction of rotation (49) and viewed from a stationary standpoint. The absolute take-off velocity (Vabs) and the absolute take-off angle (α) are determined by the magnitudes of the radial (Vr) and transverse (Vt) velocity components. As well as by the length and angle at which the guide surface (47) is arranged, the precise magnitudes of the radial and transverse velocities are determined by the friction to which the material is subjected during the movement along the guide surface (47). This is disregarded here. Viewed from a standpoint moving with the guide member (45), after it leaves the guide member (45), the material moves into a spiral path (53) directed backwards and is - in the relative sense — accelerated along this path. Figure 5 shows, for Figure 4, the development ofthe radial (Vr) and transverse (Vt) velocity components and the absolute velocity (Vabs) and relative velocity (Vrel) of the material when it moves along the guide surface (47) and is then propelled outwards from said release end (48). At the take-off location (= release end (48)) the radial (Vr) velocity component is (much) smaller than the transverse (Vt) velocity component, with the consequence that the take-off angle (α) is less than 45° (when the transverse (Vt) and radial (Vr) velocity components are identical the take-off angle (α) is 45°). From the take-off location (48) the material moves at a constant take-off velocity (Vabs) along said straight path (50), the radial (Vr) velocity component increasing and the transverse (Vt) velocity component decreasing as the material moves further away from the axis of rotation (43). At the point in time when the material leaves the guide member (45), the relative velocity

(Vrel) is (much) lower than the absolute velocity (Vabs), but the relative velocity (Vrel) then increases substantially when the material moves along the spiral path (53), whilst the absolute velocity (Vabs) ofthe material moving along the straight path (50) remains constant.

Figures 6 and 7 describe a second diagrammatic rotor (54) similar to the rotor (42) from Figures 4 aud 5, the guide surface (55) being oriented radially (51). As a result of the radial orientation of the guide surface (55) the transverse (Vt) velocity component decreases (in comparison with a guide surface (45) oriented forwards (Figures 4 and 5)), with the result that the absolute take-off angle (α) is less than 45°, whilst the take-off velocity (Vabs) also decreases, compared with an arrangement oriented forwards (56). As a result the relative velocity (Vrel) also decreases at the point in time when the material leaves the guide surface (55) and then increases less rapidly along the spiral path (57) than in the case of a guide surface (56) oriented forwards.

Figures 8 and 9 describe a third diagrammatic rotor (58) similar to the rotor (42) from Figures 4 and 5, the guide surface (59) being oriented obliquely (52) backwards, viewed in the direction of rotation (60). The radial (Vr) velocity component predominates, as a result of which the absolute take-off angle (α) increases and is greater than 45°, whilst the take-off velocity (Vabs) decreases, compared with a radial arrangement (55). The relative take-off velocity (Vrel) increases somewhat (compared with a guide member (55) oriented radially) and then increases somewhat less rapidly.

It is thus possible substantially to influence the take-off angle (α) and the take-off velocity (Vabs) with the aid of the positioning of the guide member. The absolute take-off velocity (Vabs) increases and the absolute take-off angle ( ) decreases the more the guide surface is oriented forwards (56). The absolute take-off angle (α) increases and the absolute take-off velocity (Vabs) decreases the more the guide surface is oriented backwards (55). In the relative sense the relative take-off velocity (Vrel) increases the more the guide surface is oriented backwards (59), whilst the acceleration along the spiral path (61) decreases somewhat. It is very important that the length of the long spiral path, required to reach a point a radial distance (r) away from said axis of rotation, increases the further backwards (59) the guide member is arranged, as a result of which the radiality (γ) also increases. This radiality is defined as the angle between the radial line (r) from said axis of rotation (43) having thereon the location where the long spiral path (53) is located a radial distance \r) away from said axis of rotation (43) and the contact line (62) along said spiral path (53) at the location (63) along said spiral path (53) that is a radial distance (r) away from said axis of rotation (43).

As is indicated diagrammatically in Figures 10 and 11, the guide member (39) can also be of cylindrical construction, where there is a curved (convex) guide surface (64) oriented forwards, which also has the advantage that it is symmetrical. As is indicated in Figure 12, the cylindrical shape also has the advantage that the position ofthe spiral path (66) can be accurately determined or moved by changing the diameter of the guide cylinder (65), said spiral path (66) here being displaced outwards as the diameter of the guide cylinder (65) increases, viewed from said axis of rotation.

Figures 13 to 16 now show, diagrammatically, four essentially identical rotors (67)(68)(69)(70) which can be rotated in one direction and are each equipped with four (autogenous) impact members (71)(72)(73)(74) constructed as chamber members, but with different guide members (75)(76)(77)(78), that is to say, respectively, guide surfaces oriented backwards (75) (Figure 13), guide surfaces oriented radially (76) (Figure 14), guide surfaces oriented forwards (77) (Figure 15) and cylindrical (78) guide surfaces (Figure 16), which latter guide surfaces essentially represent guide surfaces curved forwards. The spiral paths (79)(80)(81)(82) that the streams of material describe after they leave the respective guide members (75)(76)(77)(78) differ substantially (as described in Figures 4 to 12). Thus, the length ofthe spiral path (81) decreases the further forwards the guide member (77) is oriented, whilst the relative impact velocity the same radial distance (r) away from the axis of rotation does not differ a great deal. Here a shorter spiral path (81) has the advantage that the radiality (γ) a specific distance away from the axis of rotation is greater compared with a longer spiral path. The impact on the autogenous impact member (73) consequently takes place at a more open (i.e. more perpendicular) angle, what is achieved by this means being that the impact yields a higher comminution intensity, whilst the stream of material has to change direction less in order to be guided along the autogenous chamber bed towards the release end (30). On the other hand, however, the material is picked up much easier (more naturally) from the central surface (83) by a guide member (75) oriented backwards, as a result of which there is a saving in both energy and wear and a greater capacity can be achieved. A cylindrical (at least semi-cylindrical) guide member that combines the advantages of guide members oriented forwards and guide members oriented backwards as well as possible and also makes a symmetrical construction possible provides a compromise. As explained above, the problem is the wear and in particular - under the influence of this wear - the displacement ofthe long spiral path.

Figure 17 shows, diagrammatically, the influence that wear ofthe guide member (84) has on the location of the spiral path (85)(86), for a circular guide member (84) here. The spiral paths (85)(86) intersect one another a specific radial distance (r_x) away from the axis of rotation (26), that is the spiral paths (85)(86) that are achieved with, respectively, unworn (87) and worn (88) guide members (84). At a distance smaller than (r_x) the spiral path (86) moves inwards, viewed in the direction of rotation, and at a distance greater than (r_x) moves outwards. Thus, when the impact member (89) is a distance away from the axis of rotation (26) that is greater than (r_x), the location (90) where the material strikes the impact surface (91) moves outwards, and vice versa in the case where the impact surface is a distance away from the axis of rotation (26) that is less (92) than (r_x).

In practice the radial distance from the axis of rotation to the impact surface is determined by a large number of factors, inter alia symmetry, maximum achievable or desired rotational velocity and the like. As explained above, a shift in the location of impact on the impact member is frequently not desired. In order nevertheless to maintain a reasonably constant impact location as the guide member wears, the shape ofthe guide member must be adapted.

For this purpose the invention provides a guide member that is of mirror symmetrical construction - as described above - where the side surface is provided with an extended side surface section that extends further from the release end in the direction of the outer edge of the rotor as far as the outer end of the extended side surface section, which extended side surface section is located behind the radial line from the axis of rotation having the release end thereon, a smaller distance away from the radial plane of symmetry than the release end, which outer end is located a greater radial distance away from the axis of rotation than the release end and a smaller radial distance away from the axis of rotation than the impact part.

It is preferable that the extended side surface section is located behind the straight line having the release end thereon, which straight line is parallel to the radial plane of symmetry. What is achieved by this means is that as wear occurs along the guide surface the release end not only moves inwards, that is in the direction of the radial plane of symmetry, but at the same time also gradually moves outwards, essentially along said extended side surface section, with the consequence that the spiral path does not move inwards - or at least moves inwards to a much lesser extent - so that the material continues to strike the impact surface on virtually the same impact part.

Figure 18 shows, diagrammatically a first embodiment of a guide member (93) according to the invention. Here the original guide member (93) is of mirror symmetrical construction with respect to the radial plane (94) from the axis of rotation (95) and has two essentially identical side surfaces (96)(97). Each side surface (96)(97) extends between a central feed (98), where the material is picked up from the receiving and distributing member (not indicated here), and a release end (99), where the material leaves the guide member (93) and is directed into a spiral path (100) directed backwards, viewed in the direction of rotation (101) and viewed from a standpoint moving with the guide member (93). The guide surface (102), along which the material moves outwards and is accelerated under the influence of centrifugal force, extends between the central feed (98) and the release end (99). The guide member (93) is provided with an extended side surface section (103); that is the side surface (96) extends further from the release end (99) in the direction of the outer edge (104) of the rotor (105) as far as the outer end (106) of the extended side surface section (103). The extended side surface section (103) is located behind the radial line (202) from the axis of rotation (95) having the release end (99) thereon. The outer end (106) is located a greater radial distance away from the axis of rotation (95) than said release end (99) and a smaller radial distance away from said axis of rotation (95) than the strike location where the material strikes the impact surface (111). When the guide member (93) starts to wear - the typical wear pattern that is produced is indicated in three stages (107)(108)(109) - the central feed (98) and the guide surface (102) both move and the release end (99) moves along the extended side surface section (103), that is in the direction of the radial plane (94) of symmetry and in the direction of the outer edge (104) ofthe rotor (105). As explained above, the shape of the extended side surface section (103) can be so chosen that the spiral paths (100)(107)(108)(109) - the position of which is displaced as the guide surface (102) wears - continue to intersect one another at a strike location (110) a pre-indicated radial distance (r_x) away from the axis of rotation (95), i.e. the strike location (110) where the material continues to strike the impact surface (111). As explained above, the course of the spiral path (100)(107)(108)(109) or stream is influenced by a large number of parameters and under practical conditions the strike location (110) describes a certain plane that under normal circumstances is, however, limited as far as the periphery is concerned. Under practical conditions the respective impacts take place very accurately, as can be seen from the wear patterns, and the wear pattern (impact surface) moves essentially only when the guide member wears (assuming a reasonably constant grain diameter).

It is clear that it is not possible to indicate a universal shape for the extended side surface section; after all, the spiral path must move - as the guide member wears - in such a way that the grains continue to strike the impact part of the impact surface. The location of the spiral path is determined in the first instance by the position of the impact member or impact surface of the impact member and furthermore by |TJ the shape and dimensions of the guide member and [H] the shape and dimensions that are produced under the influence of wear. Furthermore, the grain diameter plays an important role because larger grains are retained longer by the guide member and consequently usually move along a spiral path that is located further outwards than the spiral path that grains of a smaller diameter describe (viewed from the axis of rotation). Furthermore, it is important that the rotational velocity does not have an influence on the location (position) of the spiral path.

The shape of the extended side surface section that has the effect that the strike location remains reasonably constant - that is to say does not move too far inwards or outwards - can differ substantially depending on said parameters, the shape of the original impact member, the shape of the wear pattern that develops and the radial distance from the axis of rotation to the strike location. In any event, the shape of the extended side surface section must comply with a number of requirements.

In the general sense, the shape of the extended side surface section is so chosen that when wear occurs on the guide surface and consequently the release end moves outwards along the extended side surface section in the direction of the outer end and inwards in the direction of the radial plane of symmetry, with the result that the material leaves the guide member at a take-off location along the extended side surface section, the material then moves along a displaced spiral path having the impact surface thereon, viewed from a standpoint moving with the guide member. It is important that the outer end is located or continues to be located a smaller radial distance away form the axis of rotation than the spiral path or the displaced spiral path. More specifically: - when the release end is located a greater distance away from the radial plane of symmetry than the central feed, the extended side surface section is located behind the straight line having the release end thereon, which straight line is parallel to the radial plane of symmetry, viewed in the direction of rotation; - when the release end is the same distance away from the radial plane of symmetry as the central feed, the extended side surface section is located behind the straight line having thereon the central feed and the release end, viewed in the direction of rotation;

- when the release end is located a smaller distance away from the radial plane of symmetry than the central feed, the extended side surface section is located behind the straight line having thereon the central feed and the release end, viewed in the direction of rotation. The outer end must in any event be:

- a greater radial distance away from the axis of rotation than the release end;

- a smaller radial distance away from the axis of rotation than the strike location. Depending on the shape ofthe original side surface section, the outer end can be in a location where:

- the difference between the radial distance from the axis of rotation to the release end and the corresponding radial distance to the central feed is equal to the difference between the radial distance from the axis of rotation to the outer end and the corresponding radial distance to the release end; - the difference between the radial distance from the axis of rotation to the release end and the corresponding radial distance to the central feed is greater than the difference between the radial distance from the axis of rotation to the outer end and the corresponding radial distance to the release end;

- the difference between the radial distance from the axis of rotation to the release end and the corresponding radial distance to the central feed is less than the difference between the radial distance from the axis of rotation to the outer end and the corresponding radial distance to the release end.

Furthermore, the outer end can be coincident with the radial plane of symmetry, but can also be some distance away from the radial plane of symmetry. As far as the shape of the guide surface is concerned, the invention provides, inter alia, the options that:

- the central feed is coincident with the radial plane of symmetry;

- the central feed is located some distance away from the radial plane of symmetry;

- the release end is a greater radial distance away from the radial plane of symmetry than the central feed;

- the release end is located the same radial distance away from the radial plane of symmetry as the central feed;

- the release end is located a smaller radial distance away from the radial plane of symmetry than the central feed;

- the guide surface extends in the direction of the outer edge of the rotor along a straight surface;

- the guide surface extends in the direction of the outer edge of the rotor along a convex surface, viewed from said radial plane of symmetry, it being possible, for example, for the convex surface to describe an arc;

- the guide surface extends in the direction of the outer edge of the rotor along a concave surface, viewed from the radial plane of symmetry;

- the extended side surface section extends in the direction of the outer edge of the rotor along a straight surface;

- the extended side surface section extends in the direction of the outer edge of the rotor along a convex surface, viewed from the radial plane of symmetry, it being possible, for example, for said convex surface to describe an arc;

- the extended side surface section extends in the direction of the outer edge of the rotor along a concave surface, viewed from the radial plane of symmetry;

- the outer end is coincident with the radial plane of symmetry;

- the outer end is located some distance away from the radial plane of symmetry; - at the location ofthe central feed, the side surface is oriented transversely to the radial plane of symmetry;

- at the location ofthe central feed, the side surface is oriented essentially perpendicularly to the radial plane of symmetry;

- at the location ofthe release end, the side surface runs essentially parallel to the radial plane of symmetry;

- at the location ofthe outer end, the extended side surface section is oriented transversely to the radial plane of symmetry;

- at the location of the outer end, the extended side surface section is oriented essentially perpendicularly to the radial plane of symmetry. Figures 19 to 22 show a number of examples of shapes of guide members. The invention is, however, not restricted to these shapes but, on the contrary, encompasses to any other shape or combination that have the effect that the spiral path moves under the influence of wear in such a way that this continues to intersect the strike location reasonably accurately.

Figure 19 shows, diagrammatically, a second embodiment of the guide member (112) according to the invention. Here the central feed (113) is a greater distance away from the radial plane of symmetry (114) than the release end (115). The guide surface (116) is of straight construction and thus oriented backwards, viewed in the direction of rotation (117). The extended side surface section (118) describes essentially an equilateral triangle.

Figure 20 shows, diagrammatically, a third embodiment of the guide member (119) according to the invention. Here the central feed (120) is located the same distance away from the radial plane of symmetry (121) as the release end (122) and the guide surface (123), which is of straight construction, thus runs parallel to said radial plane (121). The extended side surface section (124) is of straight construction and the outer end (125) is some distance away from the radial plane of symmetry (121).

Figure 21 shows, diagrammatically, a fourth embodiment of the guide member (126) according to the invention. Here the central feed (127) is some distance away from the radial plane of symmetry (128) and the release end (129) is a greater distance away from said radial plane of symmetry (128) than the central feed (127). The guide surface (130) is of concave construction, viewed from the radial plane of symmetry (128). The extended side surface section (131) is of straight construction and the outer end (132) is located some distance away from said plane of symmetry (128).

Figure 22 shows, diagrammatically, a fifth embodiment ofthe guide member (133) according to the invention. Here the guide section (134) is the same as that of the fourth embodiment from Figure 21. However, the extended side surface section (135) here is of convex construction and the outer end (136) is located some distance away from the radial plane of symmetry (137), what is achieved by this means being that the strike point (138) where the spiral paths (139)(140) continue to intersect one another is further remote from the axis of rotation (141).

Figure 23 shows, diagrammatically, a sixth embodiment of the guide member (142) according to the invention. The central feed (143) is located some distance away from the radial plane of symmetry (144) and the release end (145) is a greater distance away from said radial plane of symmetry (144) than the central feed (143). The guide surface (146) is of concave construction with respect to the radial plane of symmetry (144) and the outer end (147) is located some distance away from said radial plane of symmetry (144) and the extended side surface section (148) is likewise of concave construction. With this structural form the point of intersection is fairly close to the outer end. Figure 24 shows, diagrammatically, a seventh embodiment of the guide member (149) according to the invention. The central feed (150) is located some distance away from the radial plane of symmetry (151) and the release end (152) is a greater distance away from said radial plane of symmetry (151) than the central feed (150). The guide surface (153) is of straight construction. The extended side surface section (154) is also of straight construction. The outer end (155) is the same radial distance away from the said radial plane of symmetry (151) as the release end (152) and as a result the extended side surface section (154) is parallel to said radial plane of symmetry (151).

Figure 25 shows, diagrammatically, an eighth embodiment of the guide member (156) according to the invention. The central feed (157) is some distance away from the radial plane of symmetry (158), the guide surface (159) is of concave construction, viewed from said radial plane of symmetry (158), and the release end (160) is a greater distance away from said radial plane of symmetry (158) than the central feed (157). The outer end (161) is located a greater distance away from said radial plane of symmetry (158) than the release end (160) and the extended side surface section (162) is of straight construction and is located behind the radial line (163) from the axis of rotation (164) having the release end (160) thereon. The choice ofthe shape ofthe guide members, in particular the extended side surface section, is determined by cost price of the wear part (or to put it more accurately cost price per tonne crushed material), the requisite tool life and the radial distance at which the impact member is arranged (this is determined by the shape of the original guide member). In practice, the shape can be determined on the basis of experience and trials, whilst computer simulation is an important aid. The guide member is usually carried by the rotor with the aid of a support member, it being preferable that the guide member is provided along the outside (that is facing the outer edge ofthe rotor) with an opening - for example a slot - by means of which the guide member can be pushed over or against the support member in such a way that it anchors itself firmly under the influence of centrifugal force. Figures 26 and 27 show a first embodiment (plan view and side view, respectively) of a support member (165), the support member (165) being provided with a support plate (166) that extends mirror symmetrically along the radial plane of symmetry (167), and the guide member (168) being provided with a slot-shaped opening (169) which, from a position in the guide member (168), extends mirror symmetrically widening along the radial plane of symmetry (167) in the direction of the outer edge of the rotor (not indicated here), in such a way that the guide member (168) can be pushed with the aid of the slot-shaped opening (169) over the support plate (166) and anchors itself against the support plate (166) under the influence of centrifugal force. Here the side walls (170)(171) of the slot-shaped opening (167) diverge in the direction of the outer edge of the rotor, as a result of which the guide member (168) can be removed very easily. Along the inside (172), the support member (165) is provided with a protruding ridge (173) that fits in an opening (174) in the guide member (168), by which means the guide member (168) is prevented from being able to shift upwards under the influence of centrifugal force.

The support member can also be constructed with side walls that run parallel to the radial plane of symmetry and, instead of the support member, the guide member can be provided with a protruding ridge.

It is possible to adjust the position of the spiral path with the aid of an adjusting plate, which is pushed or positioned (not indicated here) between the support member and the guide member.

Figures 28 and 29 show, diagrammatically, a second embodiment (plan view and side view, respectively) of a support member (175) essentially the same as the first embodiment (165) from Figures 26 and 27, the slot-shaped opening in the guide member (177) not being continued upwards (179). What is achieved by this means is [IJ that no material deposits in the slot-shaped opening (176) between the guide member (177) and the support member (178), which can make replacement more difficult, and [H] that the support member (175) cannot become damaged at the top (178).

Figures 30 and 31 show, diagrammatically, a third embodiment (plan view and side view, respectively) of a support member (180), the guide member (181) being provided with an opening (182) that extends upwards from the underside (183), with the aid of which opening (182) the guide member (181) can be pushed over a rod (184) that acts as support member. To prevent the guide member (181) flying out upwards under the influence of centrifugal force, it is preferable to orient the rod (184) somewhat towards the inside, that is at an angle (α) of 1° to 3° in the direction ofthe axis of rotation.

Figures 32 and 33 show, diagrammatically, a rotor (185) that is made up of two parallel rotor blades (186)(187), between which the guide member (188) and the impact member (189) extend. The upper rotor blade (187) is supported by the support members (190) of the impact members (189). The two rotor blades (186)(187) are provided along each of the sides (192)(193) facing one another with a projection (194)(195), by means of which the guide member (188) is firmly held between the rotor blades (186)(187).

Figure 34 shows, diagrammatically, a guide member (196) that is provided with an attachment (197). Such an attachment (197) has the effect that the bottom edge (198) of the feed member (199) (feed tube) can wear down a little before this leads to disruption of the feed of the material to the guide members (196). Such an attachment (197) can be made of metal or hard metal but also of rlastic and can be fixed by means of a screw (201), but also by means of an anchoring construction under the influence of centrifugal force (or fixed in some other way). Because the attachment is not subject to major wear - this is concentrated below it (200) - the attachment (197) can be re-used. Finally, the invention provides the option of a balancing member (204) 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 (204), which balancing member (204) is provided with a circular closed tube (205), the circle axis of which is coincident with the axis of rotation (4), which tube (205) has an identical radial section all round, square in this case, viewed from the axis of rotation (4), is at least partially filled with a fluid and contains at least three solid bodies (206) which are able to move around freely in the tube (205), for reducing vibration of said rotor (1) when this become unbalanced. The radial section of the tube (205) 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 said 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 inteφretation in accordance with generally accepted legal principles, such as the principle of equivalents and the revision of components.

Claims

CLALMS

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

- a rotor (1) that can be rotated about a vertical axis of rotation (4) in both directions of rotation (203), which rotor (1) consists of at least one part and is supported on a shaft (6);

- a receiving and distributing member (7) that is carried by said rotor (1) and is provided with a receiving and distributing surface (8), the outer edge (9) of which extends in a regular manner around said axis of rotation (4), for receiving and distributing said material that is fed with the aid of a feed member onto said rotor (1) at a location close to said axis of rotation (4); - at least one guide member (2) that is carried by said rotor (1) in such a way that said guide member (2) can be removed for replacement because of wear, which guide member (2) is some distance away from said axis of rotation (4), which guide member (2) is mirror symmetrical with respect to the radial plane of symmetry (11) from said axis of rotation (4), which radial plane of symmetry (11) divides the peripheral surface (12) of said guide member (2) into two identical side surfaces (13)(14), which side surface (13) extends in the direction of the outer edge (15) of said rotor (1) and is provided with a central feed (16), a guide surface (17) and a release end (18) for, respectively, picking up at least a portion of said fed material by said central feed (16), guiding said material picked up along said guide surface (17) under the influence of centrifugal force, after which, when it leaves said guide member (2) at the location of said release end (18), said guided material is directed into a spiral path (19) directed backwards, viewed in the direction of rotation and viewed from a standpoint moving with said guide member (2);

- at least one impact member (3) that is carried by said rotor (1) and is provided with at least one impact surface (22) that is associated with said guide surface (24), in such a way that at least one impact part of said impact surface (22) is oriented essentially transversely to said spiral path (19), viewed in the direction of rotation (203) and viewed from a standpoint moving with said impact member (3), for causing the material to collide;

- characterised in that

- said side surface (96) is provided with an extended side surface section (103) that extends from said release end (99) further in the direction of the outer edge (104) of said rotor (105) as far as the outside end (106) of said extended side surface section (103), which extended side surface section (103) is located behind the radial line (202) from said axis of rotation (95) with said release end (99) thereon, viewed in the direction of rotation (101), which outer end (106) is located a greater radial distance away from said axis of rotation (95) than said release end (99) and a smaller radial distance away from said axis of rotation (95) than said impact surface (111).

2. Device according to Claim 1, wherein said extended side surface section is located behind the straight line with said release end thereon, which straight line is parallel to said radial plane of symmetry, viewed in the direction of rotation.

3. Device according to Claim 1, wherein said release end is located a greater distance away from said radial plane of symmetry than said central feed.

4. Device according to Claim 3, wherein said extended side surface section is located behind the straight line having said release end thereon, which straight line is parallel to said radial plane of symmetry, viewed in the direction of rotation.

5. Device according to Claim 1, wherein said release end is located the same distance away from said radial plane of symmetry as said central feed.

6. Device according to Claim 5, wherein said extended side surface section is located behind the straight line having thereon said central feed and said release end, viewed in the direction of rotation.

7. Device according to Claim 1, wherein said release end is located a smaller distance away from said radial plane of symmetry than said central feed.

8. Device according to Claim 7, wherein said extended side surface section is located behind the straight line having thereon said central feed and said release end, viewed in the direction of rotation.

9. Device according to Claim 1, wherein said outer end is located a smaller radial distance away from said axis of rotation than said spiral path, viewed along the radial line from said axis of rotation having said outer end thereon and viewed from a standpoint moving with said guide member.

10. Device according to Claim 1, wherein the shape of said extended side surface section is so chosen that when wear occurs on the guide surface and, as a consequence, said release end moves outwards along said extended side surface section in the direction of said outer end and inwards in the direction of said radial plane of symmetry, with the result that the material leaves said guide member at a take-off location along said extended side surface section, said material then moves along a displaced spiral path having said impact surface thereon, viewed from a standpoint moving with said guide member.

11. Device according to Claim 1, wherein the shape of said extended side surface section is so chosen that when wear occurs on the guide surface and, as a consequence, said release end moves outwards along said extended side surface section in the direction of said outer end and inwards in the direction of said radial plane of symmetry, with the result that the material leaves said guide member at a take-off location along said extended side surface section, said material then moves along a displaced spiral path having said impact part thereon, viewed from a standpoint moving with said guide member.

12. Device according to Claim 11, wherein said outer end is located a smaller radial distance away from said axis of rotation than said displaced spiral path, viewed along the radial line from said axis of rotation having said outer end thereon and viewed from a standpoint moving with said guide member.

13. Device according to Claim 1, wherein said outer end is located some distance away from said radial plane of symmetry.

14. Device according to Claim 1, wherein the difference between the radial distance from said axis of rotation to said release end and the corresponding radial distance to said central feed is equal to the difference between the radial distance from said axis of rotation to said outer end and the corresponding radial distance to said release end.

15. Device according to Claim 1, wherein the difference between the radial distance from said axis of rotation to said release end and the corresponding radial distance to said central feed is greater than the difference between the radial distance from said axis of rotation to said outer end and the corresponding radial distance to said release end.

16. Device according to Claim 1, wherein the difference between the radial distance from said axis of rotation to said release end and the corresponding radial distance to said central feed is smaller than the difference between the radial distance from said axis of rotation to said outer end and the corresponding radial distance to said release end.

17. Device according to Claim 1, wherein said guide surface extends in the direction of the outer edge of said rotor along a straight surface.

18. Device according to Claim 1, wherein said guide surface extends in the direction of the outer edge of said rotor along a convex surface, viewed from said radial plane of symmetry.

19. Device according to Claim 18, wherein said convex surface describes an arc.

20. Device according to Claim 1, wherein said guide surface extends in the direction of the outer edge of said rotor along a concave surface, viewed from said radial plane of symmetry.

21. Device according to Claim 1, wherein said extended side surface section extends in the direction of the outer edge of said rotor along a straight surface.

22. Device according to Claim 1, wherein said extended side surface section extends in the direction of the outer edge of said rotor along a convex surface, viewed from said radial plane of symmetry.

23. Device according to Claim 22, wherein said convex surface describes an arc.

24. Device according to Claim 1, wherein said extended side surface section extends in the direction of the outer edge of said rotor along a concave surface, viewed from said radial plane of symmetry.

25. Device according to Claim 1, wherein at the location of said central feed said side surface is oriented transversely to said radial plane of symmetry.

26. Device according to Claim 1, wherein at the location of said central feed said side surface is oriented essentially perpendicularly to said radial plane of symmetry.

27. Device according to Claim 1, wherein at the location of said release end said side surface is essentially parallel to said radial plane of symmetry.

28. Device according to Claim 1, wherein at the location of said outer end said extended side surface section is oriented transversely to said radial plane of symmetry.

29. Device according to Claim 1, wherein at the location of said outer end said extended side surface section is oriented essentially perpendicularly to said radial plane of symmetry.

30. Device according to Claim 1, wherein said guide member is reversible with respect to said radial plane of symmetry.

31. Device according to Claim 1, wherein said guide member is reversible with respect to the plane of rotation.

32. Device according to Claim 1, wherein said guide surface is at least partially made of a hard metal.

33. Device according to Claim 1, wherein said guide surface is at least partially made of a ceramic material.

34. Device according to Claim 1, wherein at the location of said central feed said guide member is at least partially made of a hard metal.

35. Device according to Claim 1, wherein at the location of said central feed said guide member is at least partially made of a ceramic material.

36. Device according to Claim 1, wherein said hard metal section extends along the central feed of both guide surfaces as a common central feed.

37. Device according to Claim 1, wherein at the location of said release end said guide member is at least partially made of a hard metal.

38. Device according to Claim 1, wherein at the location of said release end said guide member is at least partially made of a ceramic material.

39. Device according to Claim 1, wherein said extended side surface section is at least partially made of a hard metal.

40. Device according to Claim 1, wherein said extended side surface section is at least partially made of ceramic material.

41. Device according to Claim 1, wherein said support member is provided with a support plate that extends mirror symmetrically along said radial plane of symmetry and said guide member is provided with a slot-shaped opening that extends mirror symmetrically from a location in said guide member along said radial plane of symmetry in the direction ofthe outer edge of said rotor, in such a way that said guide member can be pushed over said support plate with the aid of said slot-shaped opening and anchors itself against said support plate under the influence of centrifugal force.

42. Device according to Claim 41, wherein the side walls of said slot-shaped opening run parallel to said radial plane of symmetry.

43. Device according to Claim 41, wherein the side walls of said slot-shaped opening diverge in the direction of said outer edge of said rotor.

44. Device according to one of Claims 41 to 43, wherein said slot-shaped opening is not open along the top of said guide member.

45. Device according to Claim 41, wherein said support plate is provided, along the upright edge facing said axis of rotation, with at least one notch and said guide member is provided, along said inside edge of said slot facing said axis of rotation, with at least one ridge, with the aid of which notch said guide member can be placed over said ridge in such a way that said guide member is not able to move upwards along said plate member under the influence of centrifugal force.

46. Device according to Claim 1, wherein the outer edge of said receiving and distributing surface extends at least as far as said central feed.

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

48. Device according to Claim 1, wherein the radial distance from said axis of rotation to said guide member is adjustable along the radial plane of symmetry with the aid of said support member.

49. Device according to Claim 1, wherein the radial distance from said axis of rotation to said guide member is adjustable with the aid of an adjusting plate in said slot between said upright edge of said support plate and said inside edge of said slot.

50. Device according to Claim 1, wherein said support member is provided with an opening, which guide member is provided with a support part, with the aid of which support part said guide member is pushed into said opening, in such a way that said guide member anchors itself in said opening under the influence of centrifugal force.

51. Device according to Claim 1, wherein said support member is provided with a pin that projects upwards from said rotor, which guide member is provided with a cavity, with the aid of which cavity said guide member is pushed over said pin, in such a way that said guide member anchors itself in said opening under the influence of centrifugal force.

52. Device according to Claim 1, wherein said guide member is provided with an attachment at the top.

53. Device according to Claim 52, wherein said attachment is removable.

54. Device according to Claim 52, wherein said attachment is at least partially made of plastic.

55. Device according to Claim 52, wherein said attachment is at least partially made of hard metal.

56. Device according to Claim 52, wherein said attachment is at least partially made of ceramic material.

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

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

59. Device according to one of Claims 1 to 58, wherein 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.

60. Device according to one of Claims 1 to 58, wherein ceramic material is understood to be a material that at least partially consists of aluminium oxide (AI2O3).

61. Device according to one of Claims 1 to 58, wherein ceramic material is understood to be a material that consists at least partially of silicon oxide (SiO₂).

62. 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 the same radial section all round, is at least partially filled with an oil-like substance and contains at least three solid bodies which are able to move around freely in said tube, for reducing vibration of said rotor when this becomes unbalanced.

63. Device according to Claim 1, wherein the position of said impact part is determined by the angle (θ) between the radial line from said axis of rotation 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 chosen 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 that location.

64. Device according to Claim 63, wherein the position of said impact part is determined by the angle (θ') between the radial line from said axis of rotation having said take-off location thereon and the radial line having thereon the location where said displaced spiral path and the path said impact part describes intersect one another, to be so chosen that the arrival of said material moving along said displaced spiral path at said location where said paths intersect one another is synchronised with the arrival of said impact part at that location.