WO2003061833A1

WO2003061833A1 - Disc for disc rotor of a shredding apparatus

Info

Publication number: WO2003061833A1
Application number: PCT/EP2002/012986
Authority: WO
Inventors: Fabio Rota
Original assignee: Satrind Srl
Priority date: 2002-01-23
Filing date: 2002-11-20
Publication date: 2003-07-31
Also published as: ITMI20020117A1; ITMI20020117A0

Abstract

A rotor is of the type consisting of a plurality of discs keyed on a rotating shaft, and each disc comprises seats (22) for tools (20) on the periphery thereof alternating with seats (24) for flow regulating fittings. According to the invention, the flow regulating fittings (14) are interchangeable on each disc, for example, according to the material to be processed.

Description

DISC FOR DISC ROTOR OF A SHREDDING APPARATUS

DESCRIPTION

The present invention refers to the field of shredding or chopping devices which are used to reduce various materials to small fragments.

The shredding devices of the prior art essentially comprise one or more rotating rollers or rotors, each of which carries a plurality of blades or knives, which cooperate with a counterblade or fixed knife. More in particular, the state of the art comprises, among many other types of rotors for shredders, rotors composed of a plurality of discs keyed side by side on a rotating shaft, each disc being shaped so as to provide peripheral housings to receive and clamp cutting tools or knives.

The state of the art also comprises cylindrical monobloc rotors having peripheral ribs protruding circumferentially and placed side by side in the axial direction of the rotor, said ribs serving the purpose of facilitating the flow of material between the rotor and the counterblade. The optimal shape and protrusion of these ribs vary according to the material to be subjected to shredding.

Thus, should it is subsequently desired to use the shredding apparatus for different materials, or should the ribs be excessively worn, it is necessary to replace the rotor. This operation involves significant times and costs, and the need to keep the different rotors required in stock.

An object of this invention is to facilitate the change of use of a shredding device from one material to another. Another object is to allow re-use of a rotor that has worn ribs.

A further object is to reduce the costs and times necessary for adaptation and to reduce storage costs and space.

These objects have been achieved with a disc for a shredding device as disclosed in claim 1. Further advantageous characteristics are disclosed in the dependent claims.

In other words, according to the invention, a disc rotor for a shredding apparatus comprises a plurality of rotor discs placed side by side. One disc o each disc is formed with peripheral housing for cutting tools and has, alternating with said housings for the cutting tools, seats and/or engagement means for flow regulating fittings. It further comprises a plurality of flow regulating fittings provided with engagement means to engage said seats, so that said discs can be completed with flow regulating fittings with different shapes according to the material to be shredded, and/or worn flow regulating fittings can be removed therefrom and intact fittings can be mounted.

The new apparatus achieves the aforementioned objects. In particular it can be adapted to operate on different materials simply by changing the flow regulator fittings on the discs, thus with a relatively fast and simple operation, and it can be used for a long time simply by replacing the worn parts thereon. Furthermore it allows a reduction of the space and cost of storing parts, with respect to known devices.

Purely exemplary non-limiting embodiments of the invention will be described hereunder with reference to the appended figures, wherein:

Figure 1 is a side view on a reduced scale of a rotor disc for a shredding device according to a preferred embodiment;

Figure 2 is a front view from the left of the disc of Figure 1;

Figure 3 is a sectional view along the sectional plane 3-3 of Figure 1;

Figure 4 is a side view of the body of the disc of Figure 1;

Figure 5 is a sectional view along the sectional plane 5-5 of Figure 4;

Figure 6 is a side view of a flow-regulating element of the disc of Figure 1;

Figure 7 is a sectional view along the sectional plane indicated by 7-7 in Figure 6;

Figure 8 is a perspective view of a cutting tool with a filling element, enlarged with respect to the preceding figure;

Figure 9 is a side view on a reduced scale of a variant of the shredding disc according to the invention;

Figure 10 is a side view of the body of the disc of Figure 9.

With reference first to Figures 1-8, a disc element of a shredding rotor according to the invention is denoted as a whole by reference numeral 10 and comprises a body 12, flow regulating fittings 14, and filling elements 16. Shredding tools or cutting knives mounted on the disc are denoted with reference numeral 20. The body 12 is generally a moulded piece of relatively rigid material, is defined externally by a cylindrical surface 18 around the axis a, and has an axial through hole 19. The through hole, in the exemplary embodiment, is hexagonal to allow keying of the disc 10 on a shaft, for example, also hexagonal (not illustrated).

The body 12 has housings 22 for tools 20 and seats 24 for the fittings 14, alternating in an orderly fashion along the circumference thereof.

Each seat or housing 22 is formed with a cavity defined on three sides by surfaces disposed like the walls of a parallelepiped, one of which, denoted by 26, extends on a fastening projection 28. The body comprises three tool-fastening projections in proximity to the three seats 22, and each projection is defined by a cusp-shaped surface, as can be seen in Figure 5. Each projection is part of the body or integral therewith and has a through hole 29 for fastening of the tool.

Each seat 24 for a flow-regulating fitting, in the example of the figures, is defined by a core 30 or engagement part, which has a substantially cylindrical circumferential surface 31, with a radius somewhat smaller than the radius of the surface 18 of the body and two radial faces 32. The radial or side surfaces or faces each have a protruding engagement peg 34, preferably in proximity to one end thereof. Only the peg 34 on one face can be seen in the figures.

Each flow-regulating fitting 14 is shaped as an arc of a circle in a side view and is substantially U-shaped in section along an axial plane, as can be seen in Figure 7, with parts 41, 42 of the U and a back 45 of the U. The cavity defined by the U shape substantially corresponds to the shape of the engagement parts 30 of the disc and in any case is suitable to receive such a part. The walls 41, 42 of the U have recesses 43 to engage the pegs 34, in proximity to one end, and have engagement teeth 44 at the other end. The back 45 of the U has a ridge 46 extending circumferentially, with a radially tapered shape that varies with the material to be shredded.

Each flow regulating fitting is mounted in position by first inserting the recess 43 on the respective peg 34, then blocking the tooth 44 with the respective filling element 16. The filling element 16 has a substantially parallelepiped shape corresponding to the seat 22 and has an offset 47 to receive and block the teeth 44. The filling element further has a N-shaped niche 48 to receive the tool.

The tool 20 is of a per se known type, with a quadrangular face with raised edges, and has a central hole to receive the screw for fastening to the projection 28.

From what has been described it can be appreciated that the invention allows flow- regulating fittings 14 of materials different from the material of the basic disc to be mounted, for example with a different resistance to wear. It also allows flow regulators with a different shape to be mounted at successive times on the same basic disc, to adapt same to form rotors to shred different materials, or to remedy wear due to prolonged use.

In Figures 9 and 10 a variant 110 of the invention is illustrated. The body 112 of the disc 110 has a substantially cylindrical outer surface 118 around the axis a of the hole 119, and the cylindrical surface is interrupted by first housings 122 evenly spaced along the periphery of the disc. The housings 122 can be of any shape suitable for the purpose, preferably, as illustrated, a shape with a rectangular profile, open to the cylindrical surface of the disc. The first housings 122 will hereunder also be called blade-holding or tool-holding housings or seats. On the side downstream of each housing the disc 110 has a projection 128 in one piece with the body of the disc. The projection 128 has a shape and dimensions correlated with the shape and dimensions of the tools 120 which must be mounted on the disc and has a through hole 129 for a tool-fastening means, generally a screw.

The tool or blade is denoted by 120 in the figures and is of a conventional type, that is to say, for example, it has a square shape in a front view with the edges raised and a central fastening hole. A filling element 116 is placed in each tool-holding housing 122 in front of the blade 120, and can have any suitable shape.

The shredding disc 110 has further housings or seats 124 spaced along the circumference thereof and alternating with the first housings 122. It further comprises a plurality of flow-regulating fittings 114. Each fitting element 114 comprises a rib-shaped body 115 and a fastening tang 117. The body has a base surface shaped as a portion of a cylinder, with the curvature substantially corresponding to the curvature of the surface of the disc, and has the ends chamfered. The tang is of such a shape and size as to be able to be received in one of the further housings 124, and is removably fixed therein with any means accessible to a person skilled in the art.

The back of the fitting 114 is tapered and has a more or less raised shape according to the material to be shredded.

The invention comprises the variants on what is described that are accessible to a person skilled in the art of normal experience, within the scope of the claims.

Claims

1. A shredder disc for a disc rotor of a shredding apparatus, said rotor being of the type that comprises a plurality of shredder discs mounted side by side on a rotating shaft and carrying shredding tools, said disc being characterised in that it comprises a body (12; 112), first housings (22; 122) for shredding tools spaced out circumferentially along the periphery of the body, further housings (24; 124) alternating with the first housings on the periphery of the body, and flow-regulating fittings (14, 114) for engagement in said further housings.

2. A disc according to claim 1, characterised in that said flow-regulating fittings (14; 114) are removably mounted on the rotor, so that they can be changed to adapt the rotor to operate on different materials.

3. A disc according to claim 1, wherein the body of the disc has protuberances (28; 128) on the periphery, adjacent the housings (22, 122) for tools.

4. A disc according to claim 3, characterised in that a tool (20) and a filling means (16) are received in each tool housing.

5. A disc according to claim 1, characterised in that the body of the disc has, in the seats for the flow regulating fittings, engagement portions (30) extending for an arc of circumference and the flow regulating fittings (14) are U-shaped in section to engage said engagement portions, the U shape comprising a back (45) with a circumferential ridge (46) and walls (41, 42).

6. A disc according to claim 5, wherein the engagement portions have lateral engagement pegs (34) protruding in proximity to one end of the respective seat and the walls of the U have recesses (43) at one end to engage said pegs.

7. A disc according to claim 6 wherein the flow-regulating fittings, at the opposite ends to that provided with a recess, have locking teeth (44), and said filling means (16) have corresponding locking offsets (47) for locking said fittings.

8. A disc according to claim 1, characterised in that the flow-regulating fittings (114) are arc-shaped and have an engagement tang (117).

9. A disc rotor for a shredding device comprising discs according to any one of the preceding claims.