_{* * * * *}

The invention concerns the building industry machines. In particular the invention relates to a machine for crushing and recovering waste materials from the demolition of buildings.

From researches carried out at national level, it has emerged that every year in Italy an average of 34 million tons of inert waste derive from building demolition work. 92% of said waste comes from small- scale demolition work. The current regulations require disposal of this inert waste in landfills; however, considerable quantities of these materials are illegally abandoned in an uncontrolled manner on public and private land, causing widespread disfigurement of the outskirts of towns which are invaded by heaps of waste. At the same time it is becoming more and more difficult to find quarry materials, as many city councils are adopting increasingly restrictive measures with regard to quarrying activity in order to protect their territory.

In recent years the development of systems for the treatment of inert residues directly on site has been given a substantial boost, due to the increased costs of transport to and disposal at the landfill: inert building materials can now be processed by movable crushing units, more commonly known as grinders, which reduce the volume of the debris directly on site and, at the end of the treatment, produce a material with a specific granulomere assortment. Such a type of system also offers the substantial advantage of complete elimination of transport costs if the crushed material is re-used directly in situ.

The grinders used for said purposes generally consist of a grinding chamber connected to an inlet hopper for the waste to be ground and to an outlet for the ground waste. The rubble grinding operation is performed by a rotor, positioned in the processing chamber and driven by suitable motor means, on which a plurality of blades consisting of steel blocks are arranged, suitable for cooperating with one or more counter blades. Near the grinding chamber screen means, or sieves, with fixed aperture are generally positioned to select the granulometry of said crushed waste and allow expulsion from the outlet only of the waste having a dimension smaller than or equal to the size determined by the screen openings, ready to be re-used for other purposes or more easily transported and disposed of. These traditional grinders have some limits and drawbacks.

The conformation and arrangement on the rotor of the blades used in the traditional grinders often requires a high-powered machine motor, with considerable consumption of energy, sometimes making it impossible to use the domestic electrical supply. A further drawback is represented by the impossibility of obtaining materials with different granulometries according to the site requirements without having to carry out long and laborious operations on the grinder sieves or in any case without stopping the machine and partially brake it down. These traditional grinders furthermore produce large quantities of more or less fine dust which, when emitted from the machine, can saturate and foul the surrounding environment, also damaging the respiratory tract of the operators employed on the site, who are in any case obliged to wear bothersome masks. Further disadvantages concern the high noisiness of these grinders, which disturbs anyone near the workplace, making their use inconvenient on sites within inhabited buildings.

The aim of the invention is to overcome these limits.

The aim of the invention is to produce a machine for crushing and recovering waste materials from the demolition of buildings that requires a reduced power of the motor and that makes it easy to produce material of different granulometries, adjusting the screening system also during the machine working.

Further aims of the invention are reduction of the power supply energy costs, reduction of dust emission, soundproofing of the machine and easy transportability thereof.

The aims are achieved by a machine for crushing and recovering waste materials from the demolition of buildings comprising:

- a frame closed by panels; - an inlet hopper for the waste to be crushed;

- an outlet for the crushed waste;

- a grinding chamber delimited by a casing and connected to said inlet hopper;

- a rotor provided with a plurality of blades consisting of steel blocks; - at least one counter blade permanently combined with said grinding chamber;

- first screen means, to select the granulometry of said crushed waste, connected to said treatment chamber; - motor means arranged for driving said rotor;

- an electrical control panel; characterized in that said steel blocks are arranged on the rotor in a discontinuous manner both longitudinally and transversally, thus partially occupying the rotor itself and so that along generic cross sections of the rotor the same number of blocks are positioned, arranged at the same angles, and in the following cross sections of the rotor the blocks are staggered from one another at a set angle.

According to a preferred embodiment of the invention, said first screen means comprise two overlapped plates, combined in a sliding manner and provided with corresponding openings for the passage of said crushed materials, in which at least one of said plates is combined with adjustment means available to the operator from the outside of the panels of said machine, arranged for allowing variation of the reciprocal position of said openings belonging to the two plates, to modify the width of the openings of the first screen means.

According to further preferred embodiments of the invention, the machine comprises second screen means comprising a first chute connected to the outlet for the crushed material. In particular, said first chute is arranged for collecting the crushed material coming out of the openings of the two plates and is provided in turn with a portion having holes for the finer fraction of said crushed material and a solid portion connected to the outlet for the coarser fraction of said crushed material.

Advantageously said machine comprises a second outlet for the finer fraction of the crushed material which passes through the holes of the first chute and drops onto suitable collection means of said second screen means, comprising a second chute connected to said second outlet.

Said second screen means are combined with a vibrating system driven by said motor means, to aid descent of the material towards the outlets.

According to a preferred embodiment, said machine is provided with a suction system connected to said grinding chamber, comprising a suction pump arranged for creating a vacuum in said chamber and filtering means for the dust arranged for emitting the treated air to the outside of the machine. In particular said filtering means comprise a cartridge filter inside the frame and a filter made of non-woven material arranged on a closing panel of the machine.

According to other embodiments of the machine, the closing panels are combined with the frame with the interposition of sound- absorption gasket elements, and the machine itself comprises wheels to facilitate horizontal and vertical movement. The advantages of the invention are evident. The discontinuous positioning of the blades on the rotor, their positioning angularly staggered between adjacent sections of the rotor itself and the fact that the rotor operates by impact of the material to be crushed against the same partially crushed material which, as long as it is still partially refined, remains on the fixed blades of the grinding body and on the first screen means, increases the production of crushed materials compared to the traditional grinders, reducing the consumption of energy per kg of product; furthermore, when larger pieces are placed in the feed hopper, machine standstills due to clogging of the rotor are avoided.

The adjustment means that allow staggering of the openings of the first screen means by means of a handle integral with the machine panel, allow the production of materials with various intermediate granulometries, without stopping the machine, without wasting time and without employing more workers, reducing all working costs.

The presence of second screen means allows the simultaneous production of material with two different granulometries according to bricklayers' needs: a larger granulometry, like crushed stone, for closing chases and other coarse work, and a finer granulometry, like sand, for the finishes.

Thanks to the 220V single-phase power supply, the invention can be used in any place of work, with connection also to the domestic electrical supply and the rationed power of the machine allows crushing of all types of building material: granites, marbles, perforated bricks and large perforated blocks, roofing, bricks, cement and plasters, synthetic materials, ceramic sanitary fittings, all types of coverings and floorings. Even more advantageously the machine can also easily crush any small ferrous objects that may be mixed with the rubble (e.g. nails, wire, etc. ...). The machine automatically stops in case of large ferrous materials in order to allow their easy removal and the machine restart without any damage to blades and rotor. The suction means with double filtering system that prevent emission of dust into the atmosphere furthermore allow the operators to work in closed environments without having to wear bothersome masks.

During operation of the machine, the vibrations are absorbed by elastic sound absorbing means that prevent transmission of the vibrations to the frame and body, minimizing noise.

Lastly, the invention can be easily transported and moved as it is provided with a system of wheels that allow for convenient transport and movement by the operator within the site, even on very steep slopes, it has compact dimensions and is relatively lightweight.

These and further advantages will be more evident in the following description which illustrates a preferred embodiment of the invention, by way of non-limiting example, and with the help of the figures in which: Fig. 1 shows, in a partially sectioned schematic lateral view, the inside of a machine for crushing and recovering waste materials from building demolition according to the invention;

Fig. 2 shows the grinder in cross section;

Fig. 3 shows an axonometric exploded view of some of the main components of the machine of Fig. 1 ; Fig. 4 shows a lateral view of the machine according to the invention;

Fig. 5 shows an axonometric view of the machine according to the invention. With reference to the Figures, a machine 1 is illustrated for crushing and recovering waste materials from the demolition of buildings consisting of a metal frame 2, closed by panels 3 with the interposition of rubber sound absorption gaskets 18, and provided with an inlet hopper 4 for the waste to be crushed and two outlets 5, 5' for the crushed waste.

Said inlet hopper 4 is connected to a grinding chamber 6, delimited by a casing 70, in which the waste is crushed. In said chamber 6 a rotor 7 is positioned, driven by suitable motor means 11 by means of a pulley 60 and a driving V belt 61. On said rotor 7, fixed by means of thrust stocks 22 screwed by means of clamping screws 23, blades consisting of steel blocks 8 are provided, arranged on the rotor itself so as not to entirely occupy its length in the direction parallel to the axis of rotation and so that along cross sections of the rotor 7 the same number of blocks 8 are arranged at the same angles, but along following sections the blocks are staggered from one another by an angle α, as it is particularly evident in Figs. 1 and 2.

In other words, the steel blocks 8 are arranged on the rotor 7 in a discontinuous manner both longitudinally and transversally, thus partially occupying the rotor itself and so that along cross sections of the rotor the same number of blocks 8 are arranged at the same angle, and in the following cross sections of the rotor the blocks are staggered from one another by a set angle α.

Preferably the blocks 8 are substantially in the shape of a parallelepiped with square base, so that they can be rotated four times before all the edges wore out and so that the side of the base of the blocks represents the thickness of said cross sections into which the rotor can be imaginarily divided.

The grinding chamber 6 is combined, by means of shoulder blocks 62, with two counter-blades 9 arranged for cooperating with the steel blocks 8 for crushing the waste.

The grinding chamber 6 is furthermore combined with first screen means 10, to select the granulometry of the crushed waste and set the maximum piece size of the crushed waste coming out of the chamber.

In particular, said first screen means 10 comprise two overlapped metal plates 20, 30 in the shape of a semi-cylindrical shell and combined in a sliding manner. Said plates 20, 30 are provided with holes 21 , 31 to allow transfer of the crushed materials from the treatment chamber 6 to second screen means 40, 50 and outlets 5, 5'. One of said plates 20, 30 is combined with adjustments means 12, substantially by means of screw 66 and nut screw 67, available to the operator from the outside of the panels 3 of the machine 1 by means of a crank 68, arranged for allowing reciprocal movement of the two plates in order to centre, or decentralize, their respective holes 21 , 31 and thus adjust the granulometry of the crushed waste passing through them.

The second screen means with which the machine illustrated is provided essentially comprise two chutes 40, 50 positioned below the two plates 20, 30.

A first chute 40 comprises a portion 41 provided with holes 42 for the finer fraction of said crushed materials, arranged so as to collect the crushed material coming out of the holes 21 , 31 of the two plates 20, 30 and a solid portion 43 connected to the first outlet 5 for conveying the coarser part of said crushed material towards the outside of the machine.

The second chute 50 is arranged to collected the crushed material coming out of the holes 42 and is connected to a second outlet 5' to convey the remaining finer part of said crushed material to the outside of the machine.

Said second screen means are combined with a vibrating system essentially comprising a pulley 13 combined with the rotor 7, connected to an eccentric 63 by means of a belt 64 and elastic supports 65. The machine 1 is provided with a suction system 14, connected to said grinding chamber 6, arranged for considerably reducing the dust produced by the crushing of the rubble. Said suction system 14 comprises a pump 15 arranged for creating a vacuum in the chamber 6 to which it is directly connected, extracting dusty air. Said dusty air is conveyed towards two filtering means 16, 17 connected to the outside of the machine 1. A first filtering element consists of a cartridge filter 16, positioned inside the frame 2. A second filtering element consists of a filter made of non-woven fabric 17, arranged on one of the closing panels 3 of the machine 1 , as illustrated in Fig. 4. With particular reference to Fig. 4 and 5, the machine comprises wheels 19, 19' combined with the frame 2, useful for manual transport of the machine by the operator, also assisted by a telescopic handle 25. The smaller wheels 19 are used to facilitate horizontal movements of the machine 1 , while a three wheels system 19' is used to facilitate the vertical movements of the machine 1 itself, making it possible to overcome architectural barriers.

An electrical control panel 100 supervises working of the components and accessory systems of the machine 1. Working of the machine 1 is illustrated below. The rubble put by the operator into the feed hopper 4 of the machine 1 is conveyed into the grinding chamber 6, where it is impacted by the steel blocks 8, provided on the rotor 7, and pushed onto the counter-blades 9 for grinding. The ground material falls onto the bottom of the grinding chamber 6 and, when it reaches the correct dimension, passes inside the holes 21 , 31 provided on the first screen means 10. The crushed material, once it has passed the first granulometric selection of the plates 20, 30, drops onto the second screen means, comprising a first chute 40 inclined towards the first outlet 5. The fraction with largest granulometry stops on the perforated portion of chute 41 and is moved, by means of the vibrating system 13, 63, 64, 65, towards the solid portion 43 of the chute 40, down to the first outlet 5. The fraction with finer granulometry, coming out of the holes 21 , 31 of the plates 20, 30, also passes through the holes 42 of the perforated portion 41 of the chute 40 and drops onto collecting means 50 also consisting of a chute, with inclination opposite to that of the first chute 40, until it reaches a second outlet 5'.

During working of the machine 1 , the operator can increase or reduce the granulometry of the material which passes through the first screen means 20, 30 by acting on the crank 68 to stagger or centre the holes 21 and 31.

Lastly, the suction system 14, by means of a pump 15, sucks the air saturated with dust from the grinding chamber 6 and conveys it towards a first cartridge filter 16 and towards a second filter made of non-woven fabric 17 positioned on one of the external panels 3 of the machine 1 , thus emitting it, completely clean, into the surrounding environment.

The invention, as described and illustrated, allow to achieve the set aims and objects.

In practice, it is clear that all the construction details can be replaced by others that are technically equivalent, likewise the materials, forms and dimensions can vary according to the needs, without departing from the protective objects of the claims.