WO1993024276A1

WO1993024276A1 - Portable machine for the abrasive treatment of floors, roads and the like, provided with a straight duct for the recovery of the abrasive material

Info

Publication number: WO1993024276A1
Application number: PCT/IT1993/000054
Authority: WO
Inventors: Berengario Gaboardi
Original assignee: TRIMMER Srl
Current assignee: TRIMMER Srl
Priority date: 1992-05-27
Filing date: 1993-05-24
Publication date: 1993-12-09
Anticipated expiration: 1994-11-27
Also published as: ITMI921302A1; ITMI921302A0

Abstract

A portable machine for the abrasive treatment of floors, roads and the like provided with a straight duct (8) for the recovery of the reusable abrasive material.

Description

"PORTABLE MACHTWK FOR THE ABRASTVE TREATMENT OF FLOORS, ROADS AND THE T.IKE, PROVIDED WTTH A STRATfiHT DUCT FOR THE RECOVERY OF THE ABRASTVE MATERIAL"

The present invention concerns the portable machines for the treatment of surfaces with abrasive particles ejected at high speed against the treated surface, and in particular refers to a portable machine for the abrasive treatment of floors, roads and the like, provided with a straight duct for the recovery of the abrasive material.

Various types of portable machines are known for the cleaning, or similar treatment by abrasion, of surfaces such as floors, roads, tracks or the like, achieved through the centrifugal high-speed throwing of small solid bodies such as steel pellets, grit and so on against said surfaces. A typical machine of this type is described in the german patent N.2.708.528.

These known portable machines are provided with a duct for the recovery of the reusable abrasive material which is conveyed towards an air-washing separator wherein the abrasive particles are divided from the dust and the scraps.

In general, this recovery duct has a decreasing cross section in the direction of the materials flow to favour their going up towards the separator.

The second fundamental characteristic common to the abrasive material recovery ducts mounted on the machines of known type is that said ducts are continuously curved, since it is believed that this shape further favours the going up motion of the materials inside the ducts. In fact, it is believed that the presence of discontinuities in the curvature of the recovery duct involves greater difficulties in going up for the materials, due to the impacts on the different segments of the duct and the consequent losses of kinetic energy of the particles.

These known ducts are usually made of manganese steel, or, in any case, of materials characterized by a particular hardness, therefore the working of each piece, and especially its curving, results long and expensive, with consequent effects on the production costs of the machines. The object of the present invention is therefore to provide a machine of the above-mentioned type wherein the recovery duct mantains unchanged the characteristic of the decreasing of the cross section in the direction of the flow of abrasive material, but whose construction results much easier and cheaper than that of the recovery ducts of known type.

This object is achieved by means of a portable machine for the abrasive treatment of surfaces provided with a duct for the recovery of the abrasive material, wherein said duct is straight.

Unlike previously believed, the recovery through a straight duct has no particular drawbacks and results as efficient as in the known type machines.

The use of said straight duct also makes available, as will be explained hereafter, more room in the upper part of the machine, so that a portable machine according to the present invention has the advantage of mounting a larger feed hopper, for the feeding of the abrasive material, compared to those which equip the known machines. Since in this type of working a fair amount of abrasive particles is wasted, a machine according to the present invention, which can be supplied with a larger volume of abrasive material, has the great advantage of a longer working endurance compared to the conventional machines.

Finally, a greater availability of room allows to use a larger volume for the separation of dust and scraps from the abrasive particles to be recycled, so that this separation results more complete and effective. Consequently, also the effectiveness of the machine is improved, said machine being fed with recycled abrasive material having a very good degree of pureness.

These and other advantages of the portable machine for the abrasive treatment of surfaces provided with a straight duct for the recovery of the abrasive material will be apparent from the following detailed description of a preferred embodiment thereof, referring to the annexed drawing which shows a schematic side view thereof.

From this figure it can be seen that the abrasive material in particles, represented by white arrows, gathered in a hopper 1 reaches, through a feed duct 2, a centrifugal wheel or rotor 3 driven in a known way by a motor 4. The abrasive material is then thrown at high speed through a throwing duct 5 and hits the surface 6 to be treated, removing an upper layer 7 which, being reduced to shivers and dust, is schematized by the dark arrows. After the impact with the surface 6, the abrasive particles go back up, mixed to the removed material 7, along a straight recovery duct 8 until they reach a chamber which forms an air washing separator 9 in its upper part, while its lower part forms the said hopper 1. The upward motion of the above-described mixture of materials inside the recovery duct 8 is favoured, besides by the kinetic energy of the materials, by an air flow directed in the same direction and generated by an aspirator (not shown) located downstream a collector 10 which collects the dust coming out from the separator 9. Inside the separator, the abrasive particles tend to fall down by gravity into the hopper 1, while the dust and scraps, being lighter, continue their travel inside the separator 9 towards the dust collector 10.

The duct 8 has converging walls in order to favour the upward motion of the materials therein. This effect may be obtained both with a continuous convergence for the whole length of the duct, as shown in the drawing, and with a duct with the initial part of constant cross section.

An accurate test has demonstrated that the use of a straight recovery duct does not compromise the effectiveness of the machine neither involves a particular wear of its components.

The figure also schematically shows with a hatched line the recovery duct 8' and the hopper 1' of a machine according to the prior art. Therefore, it is apparent that, compared to said art, the area where the separation of the abrasive particles to be recycled from the scraps takes place is much greater in the machine according to the present invention, so that the air cleaning operation of the abrasive material is more effective.

From the figure it is also apparent as much that the hopper 1 has a greater capacity than the hopper 1' of the machines according to the prior art, so that the machine according to the present invention may be supplied with a greater amount of abrasive material. Since some of said material is dispersed on the treated surface and some more is lost together with the dust and scraps, it is clear that a more capacious hopper assures a greater endurance to the machine according to the present invention.

Finally, it should be clear that, besides the straight recovery duct 8, all the elements of this machine may be of any different type suitable for the purpose.

Claims

1. A portable machine for the abrasive treatment of surfaces provided with a duct (8) for the recovery of the abrasive material, characterized in that said duct (8) is straight.

2. A machine according to claim 1, characterized in that said duct (8) has a decreasing cross section in the direction of the material flowing therein.

3. A machine according to claim 1, characterized in that said duct (8) has a constant cross section in an initial part thereof and a continuously decreasing cross section for the rest of the length, in the direction of the material flowing therein.

4. A portable machine for the abrasive treatment of floors, roads and the like provided with a straight duct for the recovery of the abrasive material, substantially as above described and illustrated in the annexed drawing.