ES2781702T3 - Disc sieve for the separation of solid materials - Google Patents

Abstract

Disc screen for solid waste separation, including: - a support structure (2); - a plurality of rotation shafts (3) parallel to each other and rotatably mounted on said support structure (2); - driving means (4) of said rotation shafts (3) to put them in rotation about their axis of longitudinal development (Y); - a plurality of disks (8) mounted axially in succession separated from each other on said rotation shafts (3), with two lateral faces (8A, 8B) orthogonal to the axis of longitudinal development (Y) of the corresponding rotation shafts ( 3) mentioned; - a plurality of sleeves (10) each of which includes a tubular body (11), and said tubular body (11) is externally loosely mounted on a corresponding rotation shaft (3) between two discs (8) in succession, and it has an inner surface (11A), directed towards said rotation shaft (3), and an outer surface (11B) directed in the opposite direction with respect to said inner surface (11A); wherein said disks (8), on the other hand, are variously mechanically rotatably coupled to said rotation shaft (3) to receive its rotation movement; the lateral faces (8A, 8B) of said disks (8) have a central circular depression (12); said disc screen is characterized in that each of said sleeves (10) has two annular supports (13), which are fixed at the ends of said tubular body (11), extending radially protruding from the outer surface (11B) of said tubular body (11) and are inserted inside the central depressions (12) of the lateral faces (8A, 8B) of said discs (8); where the annular supports (13) of each of the mentioned sleeves (10) are obtained with profiled metal plates.

Description

DESCRIPTION

Disc sieve for the separation of solid materials

Scope

The present invention relates to a disc screen for the separation of solid materials, according to the preamble of the independent main claim.

The disc sieve in question is intended for use, in a traditional way, for the separation of solid materials of different types, such as: urban solid waste, fluvial aggregates, products of organic fractions from differentiated collection, compost (for its refining), recycled wood, biomass, inert material, demolition material, soil recovery material and landfills, glass, plastic, scrap metal and other materials.

The disc screen according to the invention is therefore located in the industrial sector for the treatment of solid waste and is advantageously intended for installation at the end of the systems for crushing or grinding said waste.

Current state of the art

In the following, the term "waste" will indicate in an undifferentiated way and for brief exposition any solid material that needs to be separated into its parts according to its size or mass.

Different equipment intended for use for the separation of solid waste in various application sectors are known on the market, which also employ different construction and operating principles. Among such equipment we recall, for example: mesh screens, screw screens, disc screens, ballistic separating drum screens, fluidized bed separators, electrostatic separators, magnetic separators and other equipment.

The present invention relates to a disc-type screen, described for example in US patent 4972959. More in detail, disc screens generally include a support structure, which has numerous parallel, equidistant shafts rotatably mounted in succession between them and rotating in the same direction of rotation. A group of discs separated from each other by a distance less than the thickness of each of the discs is axially attached to each shaft, to allow the discs mounted on the adjacent shafts to be interposed so that each disc of any shaft is interposed. between two discs of the adjacent front and rear axles.

In the present field of the art, a measure that distinguishes the characteristics of the disc sieve is the sieving surface. The latter is defined as the area of the delimited openings between the discs and the rotating shafts and is indicative of the size of the waste separated by the sieve that falls by gravity below the sieving surface.

From the model DE 29711724 a screen is known in which the disks mounted on the rotating shafts are kept at a distance from each other by separating rollers directly connected to the disks and which therefore rotate together with them.

Disc screens of the known type described above have proven in practice not without drawbacks.

The main drawback is that the presence of threadlike elements among the residues to be screened, such as the presence of cables, tapes, rags, plastic bags and similar materials, affects the correct operation of the sieve. These filiform elements tend to get entangled around the screen discs and shafts and to obstruct the spaces between the discs, modifying the screening area and ultimately affecting screening operations.

Consequently, these screens often require repeated maintenance operations for cleaning interventions with the consequence of unwanted production stoppages.

In order to overcome these drawbacks, patent EP 1106264 in the name of the same applicant is known, a disc screen equipped with idle sleeves interposed between the discs with the function of avoiding or at least limiting clogging of the screening area.

In more detail, each sleeve is axially mounted on the shaft between two discs with an appropriate clearance to allow it to rotate freely on the shaft or in a tubular body provided on the outside of the shaft. From an operating point of view, the possible filiform elements that could become entangled on the outside of the idler sleeves until affecting the disks mounted on the adjacent shafts, would not alter the operation of the screen or could cause the stoppage since each sleeve, being loose with respect to the shaft on which it is mounted, it would be dragged in rotation without affecting the rotation of the shafts.

Furthermore, a sieve of the type described above is known from patent application WO-A-2011045656 in the name of the same applicant, according to the preamble of claim 1, wherein a stabilizing mass is located inside the idle sleeves to avoid or at least limit that during the operation of the screen the sleeves are dragged in their rotation by the threadlike elements causing them to become entangled.

Patent DE 102007027846 describes another example of a disc screen of the known type, which is equipped with a plurality of sleeves and each of them includes a tubular body mounted loosely on a corresponding rotating shaft between two discs in succession. Each lateral face of the discs has a central depression of circular shape intended to receive in contact the end edge of the tubular body of the corresponding sleeve.

In practice, disk sieves with idler sleeves of the known type described above have the drawback of allowing small size material, such as sand, dust, etc., to enter the gap between the idler sleeves. and the spliced discs on the shafts, thus creating a mechanical connection between the rotating shafts and the sleeves and dragging the sleeves in their rotation to the detriment of their action to avoid entanglement.

Presentation of the invention

In this situation, the problem underlying the present invention is that of eliminating the drawbacks of the aforementioned technique, making available a disc screen according to claim 1 for the separation of solid materials, the operation of which be completely reliable over time.

Another purpose of the present invention is to make available a disc screen for the separation of solid materials, which avoids the repetition of maintenance operations due to the presence of tangled threadlike elements.

Another purpose of the present invention is to provide a disk screen for the separation of solid materials, which is able to maintain the idle rotation of the sleeves provided mounted on rotating shafts.

Another purpose of the present invention is to provide a disc screen for the separation of solid materials, which is simple and inexpensive to make and completely reliable from the point of view of operation.

Another purpose of the present invention is to provide a disc screen for the separation of solid materials, which can be used in a versatile way in different fields of application.

Brief description of the plans

The technical characteristics of the finding, according to the aforementioned purposes, can be clearly seen in the content of the claims detailed below, and the advantage thereof will be more evident in the detailed description that follows, made in relation to the attached drawings, which represent an embodiment by way of example, but not exclusively, where:

figure 1 shows a perspective image of the disc screen for the separation of solid materials, according to the present invention;

figure 2 shows an enlarged detail of the screen of figure 1 in a plan view and referred to some rotation shafts with a plurality of mounted discs;

figure 3 shows the detail of figure 2 in a side view;

figure 4 shows a sectional view made on line IV-IV of figure 2;

figure 5 shows an enlarged detail of the screen of figure 1 referring to a disk with an associated sleeve in a perspective view;

Figure 6 shows an enlarged detail of the screen of Figure 1 referring to a disk with a separator and a part of the associated rotation shaft and the exploded representation of the sleeve of Figure 5.

Detailed description of a preferred embodiment example

In relation to the attached drawings, a disk screen for the separation of solid materials object of the present invention was indicated as a whole with the number 1.

The sieve 1 according to the invention lends itself to being used to separate solid materials of different types, such as: urban solid waste, fluvial aggregates, products of organic fractions from differentiated collection, compost (for refining), recycled wood, biomass, inert material, demolition material, soil and landfill recovery material, glass, plastic, scrap metal and other materials.

The disc screen 1, as schematically represented in the attached figures, includes a support structure 2, intended to be supported on the ground, and on which a plurality of rotation shafts 3 parallel and spaced apart are rotatably mounted. yes, as can be seen in the detail of the image in figure 2 that represents a plan view of the sieve.

The rotation shafts 3 have longitudinal axes of development, indicated with Y, which define a preferably horizontal position, as illustrated in the drawings, but which may also have an inclination without thereby leaving the scope of protection of the present patent.

Appropriate drive means 4 are provided to rotate the shafts 3 in the direction of rotation indicated by the arrow and bearing the reference R.

The shafts 3 all rotate in the same direction R to move the debris between an entrance door and an exit door in a completely traditional way and therefore not described in greater detail. According to a preferred embodiment of the invention illustrated in Figures 2 and 3, the drive means 4 includes an electric motor 4a and movement transmission means 5 mechanically connected to the electric motor 4a. Said transmission means 5 in turn include a chain 6 wrapped in a closed ring and coupled to a pinion 7 fixed to the motor shaft 4a and to toothed wheels 70 connected to each of the rotation shafts 3.

The screen 1 also includes a plurality of discs 8, which are axially mounted in succession on the rotation shafts 3 to receive the rotation movement therefrom.

More in detail, on each rotation shaft 3 there is mounted a group of discs 8 which, for example, according to the attached figure 2, may be formed by nine and ten discs on adjacent shafts 3 in succession.

The discs 8 of each group of discs are mounted spaced apart from each other on the development of the longitudinal axis Y of the rotation shaft 3.

The screen 1 is also equipped with a plurality of sleeves 10, each of which has a tubular body 11, which is mounted loosely on the outside on a respective rotation shaft 3 between two discs 8 in succession and has an inner surface 11A, directed towards the rotation shaft 3, and with an outer surface 11B directed in the opposite direction with respect to the inner surface 11A.

Instead, the discs 8 are mechanically and rotatably coupled in another way to the rotation shaft 3 to receive its rotational movement.

To this end, for example, the rotation shaft 3 has a male molded profile 30, defined by the shape of its outer surface and, in particular, of its cross section, and the disk 8 has a female molded profile 80 attached to said male molded profile 30, and defined in particular by a through hole suitable for receiving said male molded profile 30.

In more detail, the male molded profile 30 has a polygonal (for example, hexagonal) cross section and the discs 8 have a female molded profile 80 defined by a through hole 80 of the same polygonal shape and traversed to measure by the rotation shaft 3 which, thanks to the aforementioned form coupling, can thus rotate the disk group 8.

Preferably, each disk 8 is in the shape of a hexagonal polygonal prism with six flat faces 8C that favor the advance of the residues to be sieved during the rotation of the shafts 2. In other embodiments of the present invention, the discs 8 may also have exterior profiles of different advantageous shape suitable to favor the advance of the residues between the door of input and output.

From a functional point of view, when the sieve 1 is in operation, the motor 4a by means of the chain 6 wrapped in a ring on the pinion 7 of the crankshaft and on the toothed wheels 70 of the rotation shafts 3, rotates the rotation shafts 3 in the same direction indicated with R, and the flat-faced hexagonal profile 8C of the discs 8 collides with the waste, favoring its advance by pushing on the sieving plane in the direction of advance indicated with A in figure 1.

During this advance of the waste, those of a size smaller than that of the openings defined between the discs 8 and the sleeves 10 fall by gravity below the sieving plane, obtaining the selection of materials according to their size.

During sieving, the presence of the sleeves 10 prevents, or at least limits, the filiform residues from entangling around the rotation shafts 3. Indeed, the sleeves 10 do not follow the rotation shafts 3 during their rotation and do not they move entirely with the waste.

Each disc 8 has two lateral faces 8A and 8B orthogonal with respect to the longitudinal axis Y of the respective rotation shafts 3.

Said faces 8A and 8B are preferably substantially parallel and are oriented in different directions. According to the present invention, each of the lateral faces 8A and 8B of the discs 8 has a central depression 12 of circular shape and each sleeve 10 in turn includes two annular supports 13 that are fixed at the ends of the tubular body 11 and are they extend in a radial direction projecting from the outer surface 11B of said tubular body 11.

In particular, each annular support 13 has an outer section 13 'that extends projecting from the outer surface 11B of the tubular body 11 of the corresponding sleeve 10, extending to the outside of said tubular body 11, and developing especially substantially orthogonal to the outer surface 11B of the tubular body 11.

Each annular support 13 is inserted, preferably substantially custom-made, into the central depression 12 of the corresponding lateral face 8A, 8B of the disc 8.

Advantageously, the annular supports 13 of each sleeve 10 are fixed at the ends of the tubular body 11 through fixing means such as welds or screw means.

While the discs 8 rotate driven by the rotation shaft 3, the sleeves 10 with their annular bearings 13 remain practically stopped as they are mounted loosely on the rotation shafts 3.

The provision, object of the invention, of introducing the annular supports 13 into the central depressions 12 makes it possible to obtain the necessary clearance between the two moving parts in coincidence with a position in which the introduction of unwanted material is unlikely to occur, which would lead to connecting the sleeve 10 with the disk 8 and the rotation shaft 3 by also rotating the sleeve 10 as if it were not mounted loosely.

Otherwise, in known-type sieves, the clearance between the sleeve and the discs is obtained in the tubular body, that is, at the bottom of the space enclosed between the discs, and involves the unwanted penetration of material with the consequent formation of a joint of mechanical drag between sleeves and discs leading to tangled filiform material.

As can be seen in the attached figures 4, 5 and 6, the depressions 12 are located on a plane with a more retracted and interior position of the disk 8 with respect to the plane defined by the remaining annular parts 9 of the lateral faces 8A, 8B and in where the depressions 12 are buttressed by a recessed edge 120. Said recessed edge 120 delimits the perimeter of the depressions 12 and thus extends with an axial component within the thickness of the disc 8.

Advantageously, the sunken edge 120 of the depression 12 of each lateral face 8A, 8B of each disc 8 faces, preferably to measure, the circumferential profile 113 of the corresponding annular support 13 inserted in said depression 12.

In particular, with the term "made to measure" it is considered that the sunken edge 120 of each depression 12 faces the circumferential profile 113 of the corresponding annular support 13 with a clearance (considered as the distance between the circumferential profile 113 and the sunken edge 120) about 1-5 centimeters and preferably about 3-4 centimeters.

As a consequence, the lateral areas of the annular supports 13, that is to say the outermost faces directed towards the opposite support 13 of the same sleeve 10, are sunk within the central depressions 12 that is to say that they are slightly recessed in the disk 8 by a thickness S illustrated in figure 4.

Furthermore, advantageously the annular supports 13 of each sleeve 10 extend radially in an inner section 23 towards the longitudinal axis Y of the rotation shaft 3 and each have a through hole 130 traversed by said rotation shaft 3.

In particular, the inner section 23 of each annular support 13 extends projecting from the inner surface 11A of the tubular body 11 of the corresponding sleeve 10, and preferably has an inner edge that defines said through hole 130.

According to a preferred embodiment of the present invention, the annular supports 13 of each sleeve 10, obtained with profiled metal plates, are annular in shape, having in their center the through hole 130 so that they pass through the rotation shaft 3.

The screen 1 also preferably includes a plurality of spacer tubular bodies 14, each of which is mounted on the outside of the rotation shaft 3 and is interposed and in contact between the side faces 8A and 8B of two discs 8 in succession. Therefore, the discs 8 are introduced in succession into the rotation shaft 3 alternating them with the separating tubular bodies 14 which, pressed between the adjacent discs, rotate together with them.

Furthermore, a corresponding sleeve 10 is loosely mounted on the outside of each spacer tubular body 14.

Therefore, the longitudinal measurement D of each separating tubular body 14 defines the distance between each pair of discs 8 in succession and is slightly greater than the longitudinal measurement d of each sleeve 10, to guarantee axial clearance between the pair of discs 8 among which it is located.

In this way, each sleeve 10 can have free rotational movement around the corresponding spacer tubular body 14 in which it is mounted.

To allow a completely free rotation of the sleeves 10 in the separating tubular bodies 14, a radial clearance G is provided between them, illustrated by way of example in FIG. 4, and defined in particular between the inner edge of the inner section 23 of each bearing. annular 13 and the outer lateral surface of the corresponding spacer tubular body 14.

The discovery conceived in this way thus achieves its intended purposes.

Claims (8)

1. Disc sieve for the separation of solid waste, which includes: - a support structure (2); - a plurality of rotation shafts (3) parallel to each other and rotatably mounted on said support structure (2); - drive means (4) of said rotation shafts (3) to put them in rotation around their longitudinal development axis (Y); - a plurality of disks (8) mounted axially in succession spaced apart on said rotation shafts (3), with two lateral faces (8A, 8B) orthogonal with respect to the longitudinal development axis (Y) of the corresponding rotation shafts ( 3) mentioned; - a plurality of sleeves (10) each of which includes a tubular body (11), and said tubular body (11) is externally mounted loosely on a corresponding rotating shaft (3) between two discs (8) in succession, and has an inner surface (11A), directed towards said rotation shaft (3), and with an outer surface (11B) directed in the opposite direction with respect to said inner surface (11A); wherein said discs (8), on the other hand, are variously mechanically rotatably coupled to said rotation shaft (3) to receive their rotational movement; the lateral faces (8A, 8B) of said discs (8) present a central depression (12) of circular shape; said disk screen is characterized in that each of the mentioned sleeves (10) has two annular supports (13), which are fixed at the ends of said tubular body (11), extending radially projecting from the outer surface (11B) of said tubular body (11) and are inserted inside the central recesses (12) of the side faces (8, 8B) of said disks (8); wherein the annular supports (13) of each of the mentioned sleeves (10) are obtained with profiled metal plates. 2. Sieve disc for separating solid waste according to claim 1, wherein said depressions (12) are delimited at its perimeter by a sunk edge (120) facing measure the circumferential profile (113) of said annular support ( 13). 3. Disc screen for the separation of solid waste according to claim 1, characterized in that the lateral areas of said annular supports (13) are sunk within said central depressions (12). 4. Disc screen for the separation of solid waste according to claim 1, characterized in that the annular supports (13) of each of said sleeves (10) extend radially towards the axis (Y) of said rotation shaft (3 ) and each one of them is provided with a through hole (130) crossed by said rotation shaft (3) to allow free rotation of said sleeve (10) on said rotation shaft (3). 5. Disc sieve for the separation of solid waste according to claim 1, characterized in that the annular supports (13) of each of said sleeves (10) are fixed at the ends of said tubular body (11) through means Fixing. 6. Disc screen for the separation of solid waste according to claim 1, characterized in that it includes a plurality of separating tubular bodies (14), each of which is externally mounted on one of the mentioned corresponding rotation shafts (3), it is interposed and in contact between the lateral faces (8A, 8B) of two discs (8) in succession, and has a corresponding sleeve (10) externally mounted loosely. 7. Disk screen for the separation of solid waste according to claim 6, characterized in that the longitudinal measure (D) of said separating tubular bodies (14) is greater than the longitudinal measure (d) of said sleeves (10). 8. Disc screen for the separation of solid waste according to claim 6, characterized in that between said separating tubular bodies (14) and said sleeves (10) there is a radial clearance (G).