EP0009040A1

EP0009040A1 - Stationary enclosed cylindrical screen with rotating agitators

Info

Publication number: EP0009040A1
Application number: EP79900143A
Authority: EP
Inventors: Karl Viktor Ludwig Guth
Original assignee: Individual
Current assignee: Individual
Priority date: 1978-01-24
Filing date: 1979-08-28
Publication date: 1980-04-02
Also published as: IT1110848B; SU880238A3; DE2934889T1; GB2035848B; DE2934889C2; BR7800440A; FR2474401B1; ATA45379A; WO1979000547A1; IT7919556A0; AT361276B; AR218094A1; ES476973A1; FR2474401A1; GB2035848A

Abstract

Un ecran cylindrique fixe place dans une structure de support cylindrique (2) formee de portes demontables (2A) se compose d'une multitude de panneaux-ecrans demontables (3) pouvant avoir des mailles de grandeurs differentes; un arbre (16) (22) est monte dans l'ecran et possede des agitateurs rotatifs (17) dont on peut regler l'orientation. L'ecran a plusieurs fonctions-elevation, criblage, melange et extraction du produit - et elimine le besoin d'avoir des machines separees comme des transporteurs, des ecrans per se, des melangeurs et des dechargeurs pneumatiques; il est destine principalement au traitement des produits sous forme de grains.A fixed cylindrical screen placed in a cylindrical support structure (2) formed of removable doors (2A) consists of a multitude of removable screen panels (3) which may have meshes of different sizes; a shaft (16) (22) is mounted in the screen and has rotary agitators (17) whose orientation can be adjusted. The screen has several functions - elevating, screening, mixing and extracting product - and eliminates the need for separate machines like conveyors, per se screens, mixers and pneumatic unloaders; it is mainly intended for processing products in the form of grains.

Description

TITLE :

STATIONARY ENCLOSED CYLINDRICAL SCREEN WITH ROTATING AGITATORS

The need of a good screening in the processing of cereals represents a primary fact for obtaining final product and by-products. Cerals, such as wheat, rye, corn and others, require a processing of multiple sequential phases that lead to high purity final products, one seeking to obtain a maximum of flour extraction and a minimum of sub-products or byproducts, namely, bran.

To attain such results, very complex systems and processes are necessary, with the use of several types of machines each of which performing a specific operation with a consequent need of several phases for cereals processing. A general scheme, shown by the figure, depicts one of the possible phases to which the cereal to be transformed can be subject. Initially there are cylinders (A) through which the product enters and where the initial milling of the raw product is carried out. After the product is ground, it is carried by pneumatic raising assembly (B) which introduces said product into screens (C). These screens are composed of a series of several-mesh nylon screens through which the products sub-divide and reach new phase of processing. Such new phase begins in another cylinder going or not through intermediated blenders (D) the purpose of which is to prepare the product better for the following phase. The process will be repeated as many times as it is necessary until one obtains the maximum of extraction of the cereal to be transformed, it being pointed out that in many phases it is necessary to useremovers (E) the function of which is to eliminate possible scales that are formed during the milling.

It should be noted that such systems and processes are highly complex, requiring a very costly implantation. The solution for this problem would be a machine capable to carry out all such operations at the same time, that is: the product leaving tlie cylinder would cross the would-be machine and reach to final products and by-products, eliminating the pneumatic conveyor, the screening, the division, the removal, the intermediate blenders and simplifying the processing phases. Worrying about these facts, the applicant has developed the subject machine which carries out the operations of transport, several types of screening, division and removal. With the employment of this new concept, the pneumatic conveyor assembly and the respective cyclones, the removers, the several types of screens and intermediate blenders can be eliminated.

Another important item comprises utilizing such new concept in already-existing classic systems, processing entire phases, increasing the overall capability, not needing, therefore, a new system but using the existing one, the new machine being arranged at any point of the process.

The aims of the applicant in the subject patent refer to a new concept of cent ri f ug al screening through rotative blenders surrounded by a cylindrical screen jacket composed of multiple individually removable boards, which processes the screening of all the products of an entire phase of the industrialization process and that can be employed in all the phases. In any of such phases final products are obtained and the machine can simultaneously carried out the raising, screening, division and removal of the products.

It is convenient to point out that the process is not similar to any other systems known heretofore, it having the quality of novelty constituting noticeable technological progress. It can have industrial application and its utilization will facilitate and simplify greatly the screening in the industrialization of cereals. Now this new concept will be explained in all of its details and for better illustration of the present specification, references will be made to the attached drawings which schematically represent:

FIGURE 1 - external view of the structure.

FIGURE 2 - internal view of FIGURE 1.

FIGURE 3 - general view of the cylindrical screens jacket composed of multiple semi-cylindrical boards that can be individually removed.

FIGURE 4 - view of the screen boards showing the semirims and angles supporting it.

FIGURE 5 - demonstration of how the screen is mounted on the structure.

FIGURE 6 - schematic view of the blenders shaft for great diameters.

FIGURE 7 - ditto Figure 6,demonstrat ing the screens, too. FIGURE 8 - schematic view of the blenders shaft, in a plan. FIGURE 9 - detail of attachment of the blenders to the shaft. FIGURE 10- schematic view of the blenders shaft for smaller diameters.

FIGURE 11- schematic view of the utilization of several machines for great lenghts. FIGURE 12 - schematic view of the classic systems and processes. The machine comprises two head assemblies connected by four "T-shaped" irons (1) locat ed ymmetrically forming a circular area and with the purpose to support the structure (2) of the machine which is formed by removable doors set and attached to the "T" irons (1) by means of simple snap locks allowing total access to the multiple semi-circular screens boards responsible for the penetration of the cereals.

The semi-circular screens boards (3) are attached by snap locks (4) to two intermediate irons (5), also in the form of a "T", which are, in turn, bolted to the interal ring (6) and welded to the head assemblies. The present invention is characterized by the plurality of individually removable boards that compose the cylindrical screens jacket, which, due to the plurality of boards, are subject to a scale as to the number of type of meshes suitable to the several mesh measurements. The cylindrical screens jacket can be composed of several meshes as shown in the divisions of Figure 3, as well as it improves a systems of frame of the screens in the respective boards. Each board, which forms a semi-circle, is composed of two longitudinal angles (7) united by two, three, four or more semi-rims (8) of flat irons welded to the angles (7). The boards are superposed usually in number of 4 or in greater number, it depending on the desired scaling, and they are attached by snap locks (4) to the intermediate T-shape irons (4) as previously described. For engagement in the superpositions, the boards will have in the upper part thereof an external ring (10) in sheet metal welded or riveted to the semi-rim coated with felt (11) to fixate the superposed board and seal the junction.

As pointed out previously, the system to assemble to the screens to the boards is totally new. For such the angles (7) and the semi-rims (8) of the boards ends are drilled (13) in convenient spaces through which drilled holes the screen is properly nailed to the external side of the board. This system easily allows the partial or total replacement of the screen in the place the machine is installed.

Finally, in order to prevent the break of the steel screen caused by the vibration caused by the impact of the product thereto, if the screen were stretched and attached directly to the frame, a polyester fabric strip having flexibility and proved durability is mended to the screen in the four ends and nailed to the frame absorbing the vibrations, and by its turn-the strip (14) being protected by the sheet metal ring absorbing the impact of the products said ring is bolted or revited on the internal side of the fabric strip on small shims that preserve the flexibility of the strip. Having thus described the type of structure and the screen board responsible for the screening of the product, the mechanism by means of which the product will cross the machine ent ire ly will be described.

Initially there is a central shaft (16) to shich the blenders (17) are bolted, said shaft (16) being supported on the lower head assembly by a snap bearing which oscillates and supports the weight of the shaft (18) and another ordinary bearing similar to that one of the head assembly. In order to assure the perfect running of the shaft (18) and provide proper stiffness to the shaft (16), four flat irons or angles (19) are bolted to all the blenders (17) so as to form solid structure, eliminating the need of an intermediate bearing.

The blenders (17) are made of resilient iron or similar material and are attached to the shaft in two parts, bolted to the shaft by two bolts (20) on each side of the shaft and superposed so as to form 90-degree angles with respect to each other. From the last attaching bolt to the end, said blenders (17) are twisted to the desired helical degree for advance or transport of the product and are drilled adjacent the ends where an iron plate (21) is bolted, in an elongate bore, for adjustment of the distance to the metallic screen, said plate being broader to eliminate any void between the superposed blenders.

In case of utilization of small diameters and great lenghts of the machine, a new type of shaft has been envisaged which shaft presents the same characteristics and functional principles as the old one, but in this case the shaft (22) of the shaft or spindle (23) is made of seamless steel tube, and the blenders(24) have triple adjustment, that is: the tube (22) is drilled throughly as shown in Figure 10 in symmetric distances, a threaded circular iron bar (25) being passed from the edge of the tube to the end, which bar is tightened, for attachment, by a nut (26) on each side of the tube (22). To attach the blender (24), which is welded to a square nut (27), the iron bar (25) is followed by another nut (28) of each side of the blender for adjustment of the distance from the end of the blener to the screen (3) and also to adjust the vertical advance inclination. The inclination of the blender (24) which directs the product towards the screen, is made by the bolt (29) and lock nut (30). In the case that the machine processes a production phase requiring several divisions, a gutter-shaped sheet-metal, felt-or rubber¬-sealed collar (9) is mounted around the screen (3) and leaned to the external door, the collar having a 30º to 50º slope that crosses the door for ejection of the product; next, the section that carries out the division of the product can be mounted horizontally, this option further facilitating the approach of the product to the next machine in the processing.

The entrance (12) of the product to be screened is in the lower part of the machine, the fine product being screened first, then going through the screen and falling into the void (15) existing between the structure (2) and the cylindrical jacket composed of multiple screen boards (3) of s emi- c i r cu l ar shape, crossing the openings in the lower head assembly of the machine, reaching the funnel (31). The product of greater mesh size that did not crossed the screen is ejected from the upper part (32) of the machine.

However, in the cases that divisions are concerned, the products of the subsequent mesh sizes, in accordance with the sizes of the screens, are ejected from the gutter-shaped collars (9) and from the upper exit of the machine.

One can further invert the procedure , , , that is, the product is admitted by the upper head assembly (34) and ejected from the lower head assembly by simply inverting the rotation of the blenders shaft or, further by inversely twisting the blenders. The machine can als o be mounted horizontally.

The raising beyond six meters, although it can be made by one single machine with connected shafts and intermediate internal bearings, is preferably carried out in two, three, or four steps as shown in Figure 11, thus avoiding connected shafts and internal bearings, each part having only one rolling bearing in each head assembly, and a snap bearing in the lower head assembly, all of them being duly sized and easily reacheable. The driving is individual by means of electric motor, through belt in the upper head assembly. The upper exit (32) of the machine is provided with an oppening covered by a sheet metal cover held on the upper part with a shaft or two pins that can rotate easily in case of clogging in the product flow beyond the machine. The machines, which are supplied in modules in order to provide great lenght, have their structures reinforced by an iron arc divided into four parts bolted to the *T* irons at symmetric distances. The attachment of the machine is made by means of bolts that hold it on angles welded to the floor and walls at proper distances.

The versatility of the present invention must be pointed out for besides being capable to be utilized in all phases of the industrialization process including the first phase, allways obtaining final products and alleviating noticeably the subsequent phases of the processing, the machine being capable to be made in several different sizes, so that it is being possible to suit it to the availability of space in already-existi installations, and with the characteristic that it can be mounted verticaly and horizontally.

The new concept and great advantage of the present invention are in the fact that it can carry out simultaneously, besides screening, the raising, division and removal of the product in one single machine consequently eliminating the utilization of the machines utilized in the classic schemes of industrialization, it being also characterized by the simplicity and lightmess of the structure supporting it, by the easily and totally removable external doors by simply handling the snap locks permiting, total access to the screens jacket; by the innovation of the composition of the screens jackets constituted of multiple boards and removable by simple snap locks; by the innovation of the new concepts or blenders-shafts; as well as by the idealization of a systems of several exists of products by gutter-shaped collars.

Claims

T H E C L A I M S 19) "NEW CONCEPT OF CENTRIFUGAL SCREENING" characterized by the fact that the machine is constituted of two head assemblies connected by four irons in the form of "T" (1) located symmetrically forming a circular are and having the purpose of supporting the structure (2) of the machine, which structure is formed by removable doors laid and attached to the T irons (1) by simple snap locks, permitting total access to the multiple semi-circular screen boards (3) responsible for the screening of the cereals.

29) "NEW CONCEPT OF CENTRIFUGAL SCREENING" characterized by the fact that the semicircular screens boards (3) are attached by snap locks (4) to two intermediate irons (5) also in the form of "T" which turn are bolted to the internal ring (6) and welded to the head assemblies; and by the plurality of individually removable boards that compose the cylindrical screens jacket (3), that by the plurality of boards, are totally adjustable as to the number or type of meshes suitable to the several mesh sizes, the cylindrical screens jacket being composed of different meshes as well as innovating a system of frame of the screens in the respective boards; each board forming a semi-circular, constituting two longitudinal angles(7) united by two, three, four or more semi-rings (8) of flat iron welded to the angles (7) ; said boards being superposed and attached by snap locks (4) to the intermediate "T" irons (5) ; for engagement on the super¬

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A W:PO positions, the boards will have in the upper part a sheet metal external ring (10) welded or revited to said semi-rim, felt-coated (11), to attach the superposed board and seal the junction; to mount the screens on the boards, the angles (7) and the semi-rims (8) of the boards ends are drilled in convenient spaces through which drilled holes the screen is nailed with proper nails to the external side of the board, this system permitting easily the partial or total replacement of the screens at the site of the machine; to avoid the break of the steel screen, a flexible, polyester fabric strip is mended to the screen on the four ends, which strip is nailed to the frame, absorbing the vibration and in turn the atrip is protected by a sheet metalring (14) that absorbs the impact of the product, said ring being bolted or revited on the internal side to the fabric strip on small suitable shims that preserve the flexibility of the strip.

39) "NEW CONCEPT OF CENTRIFUGAL SCREENING" characterized by the fact that the mechanism in which the product will cross the machine is provided with a central shaft (16) to which the blenders (17) are bolted, said shaft (16) being supported on the lower head assembly by an oscillating snap bearing that supports the weight of the shaft (18) and another or-dinary bearing identical to that of the upper head assembly and to assure the perfect running of the shaft (18) and to provide proper stiffness to the shaft (16) four flat irons (19) or angles are bolted to all the blenders (17) in order to form a solid structure, eliminating the need of intermediate bearing; said blenders (17) being attached to the shaft in two parts, bolted to the shaft by two bolts (20) on each side of the shaft and superposed so as to form 909 angles between each other; from the last lock bolt to the extremity, the blenders (17) are twisted to the desired helical degree for advance or transport of the product and they are drilled adjacent the ends where an iron plate (21) is bolted, with an elongate hole for adjustment of the distance to the screens boards, said plate being broader for eliminating any void among the superposed blenders.

49) "NEW CONCEPT OF CENTRIFUGAL SCREENING" characterized in accordance with the prevfaus claims by new type of shaft, with the same functional characteristics as that claimed previously in the case of utilization of small diameters, the shaft (22) of the shaft or s p i nd l e (23) being a steel tube, the blenders (24) having triple adjustment, that is, the tube (22) is throughly drilled at symmetrical distances, wherein threaded circular iron bars (25) cross the tube from the edge thereof to the extremity which is pressed to be attached by nut (26) on each side of the tube (22) ; to attach the blender (24) which is welded to a square nut (27) to the iron bar there is another nut (28) on each side of the blender to adjust the distance of the extremity thereof to the screen (3) and .also to adjust the advance vertical inclination; the inclination of the blender (24) that directs the product towards the screen being made by bolt (29) and lock nut (30).

59) "NEW CONCEPT OF CENTRIFUGAL SCREENING" characterized by the entrance of the product to be screened, which entrance will be in the lower part of the machine, the fine product being screened first, ranspassing the screen and falling into the existing gaps (33) between the structure and the cylindrical jacket composed of multiple screened boards (3) of semicircular shape, crossing the openings existing in the lower head assembly of the machine, reaching the funnel (31); and the bigger mesh size product, which did not cross the screen, is ejected from the upper part (32) of the machine; one can further do it reversely, that is, entrance of the product through the upper head assembly (34) and exit through the lower head assembly by simply inverting the rotation of the blenders shaft of further by the inverse torsion of the blenders; the horizontal mounting of the machine being possible; and for great raisings the utilization of several machines is possible containing just one bearing in each head assembly and a snap bearing in the lower head.

69) "NEW CONCEPT OF CENTRIFUGAL SCREENING" characterized by the exit of products through gutter-shaped, sheet-metal collars (9) mounted around the screen(3) and leanded against the external door, the collars being sealed with felt or rubber, with a slope, crossing the external door for ejection of the product.