EP0620762A1

EP0620762A1 - Chopping device, and a chopper blade for such a device.

Info

Publication number: EP0620762A1
Application number: EP93901685A
Authority: EP
Inventors: Dieter Knauss
Original assignee: Individual
Current assignee: Individual
Priority date: 1992-01-15
Filing date: 1993-01-14
Publication date: 1994-10-26
Anticipated expiration: 2013-01-14
Also published as: DE59302112D1; EP0620762B1; WO1993013860A1; DE4200796A1

Abstract

Un broyeur (10) comprend un rotor cylindrique (18) pourvu d'éléments tranchants (28) et sert notamment à broyer des déchets de bois. Le rotor (18) présente une surface essentiellement lisse (26) et les éléments tranchants (28) ont un profil péripherique triangulaire dont un des côtés est situé à la surface (26) du rotor (18). Ce broyeur est très fiable, a une longue vie utile et permet d'obtenir un matériau broyé très homogène de manière très économique.A shredder (10) comprises a cylindrical rotor (18) provided with cutting elements (28) and is used in particular for shredding wood waste. The rotor (18) has a substantially smooth surface (26) and the cutting elements (28) have a triangular peripheral profile with one side located on the surface (26) of the rotor (18). This crusher is very reliable, has a long useful life and allows to obtain a very homogeneous ground material very economically.

Description

DESCRIPTION

Shredding device and knife element for a shredding device

TECHNICAL AREA

The present invention relates to a comminution device with means for supplying objects, in particular wood waste, to a drivable, cylindrical rotor device with knife elements for comminuting the wood waste, and in particular with a perforated screen device which surrounds the rotor device in some areas. The invention further relates to a knife element for a comminution device with a rotor device equipped with knife elements. Such crushing machines are able, for. B. Pallets, chisels, coated chipboard, etc. to process in compact firewood chips. In addition to a favorable price / performance ratio, high reliability and a long service life are expected from such devices.

STATE OF THE ART

In known wood shredding machines, for example, a hopper is filled with wood waste by machine or by hand by tipping over a storage container. An existing hydraulically controlled feed unit presses the filling material onto a slowly running profile rotor device. This profiled rotor device has, as knife elements, square plate elements which are offset in a rectangular groove provided in the form of a helix in the circumference of the rotor device, so that they run in the longitudinal direction of the rotor device in the form of a spiral. Such wood crushing machines have been used reliably for a long time. However, the manufacture of the rotor device is relatively complex since a helical rectangular groove on the Surface of the rotor device must be made. Furthermore, there is a relatively large distance between the counter-knife device of the comminuting device and the rotor device with knife elements, which has an unfavorable effect on the duration of the comminuting process. Because the knife elements are arranged in the form of a spiral on the rotor device, the wood waste to be shredded or parts thereof thereof are shifted to one side in the longitudinal direction of the rotor device as a result of the rotation of the rotor device, which has an adverse effect on the homogeneity the crushed wood waste mass. In addition, the noise pollution when operating such comminution devices is not insignificant.

PRESENTATION OF THE INVENTION

The invention is based on the technical problem of specifying a comminuting device which is improved compared to the prior art mentioned and which has a simple and robust structure, is economical to manufacture and, in addition to high reliability and a long service life, a great homogeneity of the comminuted wood material guaranteed. Furthermore, the invention is based on the problem of specifying an improved knife element with which the rotor device of a comminution device, in particular of the type mentioned at the beginning, can be equipped.

The shredding device according to the invention is given by the features of claim 1. The knife element according to the invention is given by the features of claim 9. Advantageous designs of the comminution device or the knife element are the subject of further subclaims.

The comminution device according to the invention is accordingly characterized in that the rotor device essentially Chen has a smooth surface and the knife elements have a triangular peripheral contour, which are arranged with a triangle side directly on the surface of the rotor device. The knife elements are preferably designed as equilateral triangular plate elements. Due to the smooth surface of the rotor device, the additional incorporation of the right-angled helical grooves, as in the known woodworking devices, can be omitted. Because the cutting tip can be formed with an angle of less than 90 degrees due to the triangular contour of the knife element, there is a better wedge effect than with the cutting corners of the square knife elements with 90 degrees. With the 90-degree cutting tip of the known knife elements, the wood waste is squeezed more than sheared, which has an unfavorable effect on the homogeneity and the processing time for reducing the wood waste. Due to the relatively good wedge effect at smaller angles of the cutting tip of the comminution device according to the invention, very good results are achieved in terms of processing time and comminution quality. When using equilateral triangular plate elements, a total of six cutting edges are produced, which can be used in succession by rotating or turning the knife element for comminuting the wood material. At the same time, by arranging a triangular side of the knife element on the surface of the rotor device, the knife element itself is automatically locked by being placed on it.

In a structurally preferred embodiment of the comminution device according to the invention, the knife elements are arranged along two opposing screw lines in the circumferential direction on the rotor device. By means of these two opposing screw line arrangements, the wood material to be shredded in front of the rotor device is not displaced in one direction as in the known shredding devices. Rather, one is more or less permanently uniform distribution of the wood material present between the knife elements and the counter knife device is guaranteed. Each knife element is preferably assigned a knife carrier element fastened on the surface of the rotor device, which can be fastened in a simple manner by means of a welded connection on the rotor device. A particularly simple embodiment with regard to the replacement of the knife elements or the change in the position of the knife elements, in the event that a cutting edge has become blunt, is characterized in that the knife element has a recess with an internal thread and the associated knife carrier element Has recess, wherein both recesses are in alignment when the knife element is placed on the knife carrier element and the knife element is detachably fastened to the knife carrier element by a fastening screw which can be inserted from the recess of the knife carrier element.

In order to meet the relatively high loads and to ensure a long service life of the knife element, the knife element in the edge region of the recess has a cross-sectional reinforcement on at least one side, which is preferably conical. As a result of this cross-sectional reinforcement, the forces acting on the knife element during the comminution process are distributed over a larger cross-sectional area, so that lower stresses arise which reduce the stress on the knife element and increase its service life.

The knife carrier element preferably has a configuration which is designed in accordance with the cross-sectional reinforcement of the knife element and into which the cross-section reinforcement is introduced before the knife element is fastened, as a result of which a certain locking is achieved. Further embodiments and advantages of the invention result from the features further specified in the claims and from the exemplary embodiment given below. The features of the claims can be combined with one another in any way insofar as they are not obviously mutually exclusive.

BRIEF DESCRIPTION OF THE DRAWING The invention and an advantageous embodiment and development thereof are described and explained in more detail below with reference to the example shown in the drawing. The features to be gathered from the description and the drawing can be used individually or in combination in any combination. Show it:

1 shows a schematic perspective of an inventive shredding device with a rotor device with triangular knife elements in an overview,

2 shows a schematic perspective illustration of a rotor device with triangular, spirally arranged knife elements and a counter knife device,

3 front view of a triangular knife element,

Fig. 4 side view of a. 3,

5 side view of a knife element screwed to a knife carrier element according to FIG. 3,

6 is an exploded perspective view of a triangular knife element with associated knife support element and fastening screw and 7 shows a schematic illustration of the combing of the knife elements in the counter knife device, the rotor device and counter knife device being arranged at a distance from one another.

WAYS OF CARRYING OUT THE INVENTION

A comminution device 10 has a funnel-shaped container device 12 on the upper side. The container device 12 has a rectangular top opening for filling with wood waste, a transverse side of the container device 12 being arranged obliquely so that the wood waste to be filled can easily reach a plate level 14 on the underside. The wood waste located on the plate level 14 is pushed towards a rotor device 18 by means of a slide device 16. The slide device 16 is moved via a gimbal-mounted hydraulic cylinder, the drive and control elements of the hydraulic cylinder 20 not being shown in FIG. 1. The design of the drive and control elements is known to the person skilled in the art. The rotor device 18 is driven via a drive unit 22 by means of a V-belt 21 and rotates relatively slowly about its axis of rotation 23. The control devices for the drive unit 22 are not shown in FIG. 1 for the sake of clarity. On the side facing the viewer in FIG. 1, in the area of the rotor device, a perforated screen device 24 in the form of a circular section is arranged in regions around the rotor device 18, which has a hole pattern 25 with a predetermined spacing and diameter of the holes.

The cylindrical rotor device 18 has a smooth surface 26. The axis of rotation of the rotor device 18 is arranged substantially perpendicular to the sliding direction of the slide device 16. On the smooth surface 26 of the Rotor device 18 is arranged knife elements 28 which have the shape of equilateral triangular plate elements. Here, a triangle side lies directly on the smooth surface 26 of the rotor device 18. The anchoring of the knife elements 28 on the rotor device 18 is further described below.

The knife elements 28 are arranged in a spiral shape around the surface of the rotor device 18. The arrangement is selected such that the knife elements 28 form two opposing spirals (S1; S2) in the circumferential direction of the rotor device 18 (FIG. 2). At the level of the plate plane 14 there is a counter knife device 30 which, according to the outer contour of the knife elements 28, has triangular grooves 32 which form an angle of 60 degrees and are arranged in the transverse direction parallel to the axis of rotation 23. For reasons of clarity, the counter knife device 30 in FIG. 2 is spaced from the rotor device 18 and is shown in front of the rotor device 18. In the crushing device 10 according to FIG. 1, the counter knife device is located behind the rotor device, the grooves 32 facing the rotor device.

Below the perforated sieve device 24, a catch device 34 for the shredded wood material is shown schematically. The shredded wood material is removed to the outside from the catching device 34 by means of a transport screw (not shown). Alternatively, it is also possible for the comminuted wood material to be suctioned off.

The shredding process now proceeds as follows. After the wood waste has been filled into the container device 12, the wood waste is fed to the rotor device 18 by means of the slide device 16. As a result of the rotation of the rotor device 18, the wood waste becomes between the knife elements 28 of the rotor device 18 and the counter knife device 10 pressed through, the wood waste is crushed by shear and crushing forces. The perforated screen device 24 surrounding the rotor device 18 determines the size of the shredded wood chips falling into the catching device 34. Depending on the hole diameter of the perforated sieve device 24, the chips can have different dimensions. By arranging the knife elements 28 in the form of two opposing spirals on the surface of the rotor device, the wood material to be shredded is distributed relatively evenly over the entire width of the rotor device 18 at the shredding location between the counter knife device 30 and the knife elements 28. This ensures a relatively high homogeneity of the shredded wood material and also causes the knife elements 28 to be worn out relatively evenly, whereas this is not the case with the known shredding devices, since the knife elements are arranged in the form of a single spiral and as a result of the rotation of the rotor device the resulting wood material is shifted to one side of the rotor device depending on the inclination of the spiral and the knives arranged there are therefore subject to greater wear.

By arranging two counter-rotating spirals equipped with triangular knife elements 28, the double output is achieved with the same power requirement compared to the known shredding devices. The equalization of the comminution process over the entire width of the rotor device in the area of the counter-knife device 30 also results in significantly less noise during cutting than with the known devices.

This is due, among other things, to the fact that in a section transverse to the longitudinal axis of the rotor device 18 there are at least two knife elements 28 in the comminution device according to the invention, whereas only one knife in each case in the known comminution devices is present, so that even relatively high squeezing noises occur during the shredding process.

The comminution effect is also improved by the advantageous choice of equilateral triangular knife elements 28, since here the cutting edge 35 is only 60 degrees, whereas in the known comminution devices with the square plate knife elements the cutting edge is 90 degrees. In the case of the latter plate elements, the wood material obtained is more squeezed, while in the knife elements according to the invention, the comminution takes place primarily by means of a shearing process due to the relatively sharp cutting edge.

To attach the knife elements 28, each knife element 28 is assigned a knife carrier element 36 which has a substantially triangular cross-sectional shape. The cross-sectional dimensions of the knife carrier element 36 are selected to be somewhat smaller than those of the knife elements 28. The knife carrier element 36 is fastened to the surface 26 of the rotor device 18 via weld seams 38. In this case, the knife carrier element 36 has a larger dimension in its longitudinal direction than the knife element 28 itself. The underside of the knife carrier element 36 is adapted to the cylindrical surface shape of the rotor device 18. The measuring element 28 has a central recess 40 with an internal thread 42. Correspondingly, the knife carrier element 36 has a recess 44, the recess 44 and the recess 40 being in alignment when the knife element 28 is attached. To reinforce the knife element 28, an essentially conical cross-sectional reinforcement 46 is present in the edge region of the recess 40 on both sides of the knife element 28. Correspondingly, the recess 44 of the knife carrier element 36 has a conical recess 45 with a linearly variable radius in the area of the cross-sectional reinforcement 46 of the knife element 28. To attach the knife elements 28, this is now placed on the knife carrier element 36, as a result of which the cross-sectional reinforcement 46 designed as a centering cone engages in the recess 45 designed as a receiving cone, and from behind a fastening screw 48 is inserted into the recess 44, which is then inserted into the internal thread 42 of the recess 40 is screwed in. The knife element 28 acts like a screw nut. This simple type of attachment makes it possible to easily detach the connection between the knife carrier element and the knife element 28 if necessary, so that a worn cutting edge of the knife element 28 can be replaced by a sharp cutting edge by turning or turning the knife element. In addition, the screw can be temporarily secured against rotation by applying an adhesive to the internal thread. A total of six cutting edges are available in the knife element according to the invention, which can each be used in a simple manner if required.

The arrangement of the triangular knife elements shown on the smooth surface 26 of the rotor device 18 is only one of the many possible variants. In particular, the pitch of the spirals and the number of knife elements in the circumferential direction can be adapted to the particular conditions required. It is also possible according to the invention to provide a plurality of opposing spirals equipped with knife elements.

The knife elements, which are often referred to as indexable inserts, are made of a special steel, in particular

16 NmCr5, made and case-hardened in a known manner.

In contrast to the shredding device according to US Pat. No. 3,202,369, in the shredding device according to the invention there is a through hole with a receiving and centering cone (recess 45 or cross-sectional reinforcement 46). available. As a result, the sleeve present in the known device can be dispensed with, since the transverse forces are absorbed by the cross-sectional reinforcements according to the invention on the knife element and thus do not act on the screw thread. In contrast to the device according to US-A-

3,202,369, the knife support for securing against rotation is not present on the knife carrier element, but rather directly on the rotor, i. H. the outer surface of the rotor forms the contact surface and thus the anti-rotation device of the knife element. Nor is it

a screw head is present. According to the screw head is not countersunk, so that the effort for providing a countersink is not necessary. There is also no need to provide a sleeve in order to keep the thread free of transverse forces, since there is a cross-sectional reinforcement on the knife element.

In its basic form, the knife according to the invention preferably consists of an equilateral triangle. For the purpose of better service life, the triangle tips of the triangle are designed as surfaces, the width of which can be adapted to the respectively required conditions. By doing without the top. Formation of the triangle corner point, a longer service life of the device is achieved according to the invention.

Instead of the smooth through bore within the knife (knife element) disclosed in US Pat. No. 3,202,369, a thread is attached according to the invention. The knife is thus releasably attached to the knife carrier element. It is not necessary to provide a mother. A security of the screw against loosening is provided according to the invention in that either a locking washer is arranged between the knife and knife carrier element, which claws between the knife carrier and the knife element when the screw is tightened and / or an adhesive is provided within the thread. According to the invention, the arrangement of the knife elements on the rotor consists of two opposing screw lines. At the same time, however, it has proven to be advantageous that the

05 Principle V-shaped knife-free areas to be filled with other knives. This results in further helical lines provided with knives. The distance from knife to knife on the circumference is determined by surface lines which have a distance from one another that can be divided in the circumference of the rotor. With this one

10 division, the knife carrier elements with the rotor already welded on, that the counter knife mesh.

According to the invention, the counter knife consists of one or more flat steel pieces with corresponding lengths. On . one of the two long sides, the blades are milled in the form of serrations so that there is a sharp corner that can be used for cutting on the upper and lower sides.

20 The counter knife is screwed onto the knife carrier, which is fastened in the frame, preferably by means of countersunk screws. The counter knife is fixed in position with the countersunk head of the screw. When turning or when replacing the counter knife, this is caused by the countersink and the countersunk screws

25 always brought into the original position.

In the exemplary embodiment according to the invention shown schematically in FIG. 7, the knife carrier elements fastened to the welded on the rotor device 18 mesh

30 knife elements 60 only in the area of their tip in the corresponding recess 62 of the counter knife device 64. This is because the width of the knife elements 60 arranged on the rotor side is greater than the width of the recesses 62. In this case, between the rotor device 18 and the counter knife

35 device 64, a gap 66 is present. On the one hand, this has the consequence that in the area of the tip of a prong 68 the an additional crushing edge is created, which has a favorable effect on the crushing of the filled, inhomogeneous material. In addition, it is ensured that elements which are not suitable for comminution can fall through the gap 66, such as in particular

Nails that are hammered into the waste wood that is fed in and as a result the cutting edges of the knife elements 60 or the counter device 64 are not exposed to any great wear.

Claims

EXPECTATIONS

01) Comminution device (10) for material of all kinds, in particular wood, with a drivable, essentially cylindrical rotor device (18) with knife elements, to which objects for comminution are fed, characterized in that the rotor device - (- 18) essentially has a smooth surface ( 26), the knife elements (28) have an essentially triangular peripheral contour and are arranged with a triangular side directly on the surface (26) of the rotor device (18).

02) Shredding device according to claim 1, characterized in that the knife elements (28) are designed as equilateral Dreieckplatten¬ elements. - ^• • - ^•

03) Comminution device according to claim 1 or 2, so that the knife elements (28) are arranged in the circumferential direction on the rotor device (18) along at least two opposing screw lines (S1, S2).

04) comminution device according to one or more of claims 1 to 3, d a d u r c h g e k e n e z e i c h n e t that each knife element (28) on a surface (26) of the rotor device (18) attached to the knife carrier element (36) can be attached.

05) Shredding device according to claim 4, characterized in that the knife element (28) has a recess (40) with internal thread (42) and the associated knife carrier element (36) has a recess (44), both recesses (40; 44) are in alignment when the knife element (28) is placed on the knife carrier element (36) and the knife element (28) is fastened by a fastening screw (48) which can be inserted from the recess (42) of the knife carrier element (36). is releasably attachable to the knife carrier element (36).

06) Comminution device according to claim 5, so that the knife element (28) in the edge region of the recess (40) has a cross-sectional reinforcement (46) at least on one side.

07) Comminution device according to claim 5, so that the knife carrier elements (36) are fastened to the rotor device (18) by means of a welded connection (38).

08) Comminution device according to claim 6, so that the knife carrier element (36) has a shape (44) shaped according to the cross-sectional strengthening (46) of the knife element (28).

09) knife element (28) for a comminution device in particular according to one or more of claims 1 to 8, wherein the knife element (28) is designed as a triangular plate element, characterized in that the knife element (28) has a recess (40) with an internal thread (42).

10) Knife element (28) according to claim 9, so that the knife element (28) in the edge region of the recess (40) has a cross-sectional reinforcement (46) at least on one side.