The present invention relates to a booth of an improved type for applying powder paint, in particular for automatic plants for painting products.
As is known, plants for painting products dedicated to use of powder paints are provided with one or more booths in which the product undergoes one or more series of treatments, for example one or more painting stages and/or one or more stages of baking/cross-linking with IR or UV lamps or with hot air.
In particular in the case of electrostatic powder painting, booths normally have a structure that comprises a frame or framework, which supports a plurality of walls positioned in such a way that their internal surface will define a space designed to house one or more dispensers of painting material. Painting is carried out by causing the products to be treated to pass in the internal space of the booth in such a way that they are exposed to dispensing of the powder by purposely provided dispensers. The dispenser is in turn moved, for example along a vertical axis, so as to increase its working capacity.
The structure of the booth, and in particular of the walls, is intended to perform two fundamental functions. A first function regards the need to have deposition surfaces on which the powder that does not adhere to the product can be deposited so as to prevent its diffusion in the surrounding environment. A second function regards the need to remove the unused powder from the walls on which it has deposited in order to recover and reuse said powder, and above all in order to prevent, in subsequent painting operations, the powder from detaching and depositing on the products contaminating their final colouring.
For this purpose, known in the state of the art are different solutions that enable cleaning of the surfaces and of the internal space of the booths, which, however, although enabling an adequate removal and recover of the powders, present some disadvantages.
In particular, a first solution consists simply in the manual intervention by operators who remove the powder deposits from the walls and from the internal space of the booth. An alternative, which also requires manual intervention, involves instead removal and replacement of the sheets that form the walls at each colour change. It is, however, evident that said solutions, albeit effective, have a negative impact on the times and costs of production and force the operator to work in an unhealthy environment.
In order to avoid manual intervention, other solutions contemplate the use of walls provided with mobile sheets, generally made of deformable material, such as, for example, plastic sheets, which, through purposely provided actuation systems, are moved with respect to the system for removal of the painting powder. Said solution enables elimination of any manual intervention on the part of operators and relatively effective removal of the powder, but presents in any case some drawbacks.
For example, a manual intervention is in any case necessary for cleaning the internal space of the booth and the devices present therein, for example, paint guns or, in general, dispensers. In order to avoid manual intervention, other solutions contemplate use of walls made of rigid plastic material, with the possibility of automatic cleaning via purposely provided motor-driven apparatuses. This system limits the possibility of vertical development of the booth and moreover presents the drawback of being very costly.
A primary task of the present invention is to provide a paint booth, and in particular a paint booth for automatic plants for painting products, which will enable the problems referred to above to be overcome.
In the framework of the above task, a purpose of the present invention is to provide a paint booth that will not require, or in any case will minimize, manual cleaning interventions. Another purpose of the present invention is to provide a paint booth that will enable effective removal of the residue of painting material that is deposited on the walls of the booth.
A further purpose of the present invention is to provide a paint booth in which the paint-dispenser devices will be adequately protected from deposits of painting material.
Yet a further purpose of the present invention is to provide a paint booth that will enable an adequate cleaning not only of the walls but also of the space inside the booth, minimizing the risks of contamination between different painting lots.
Another purpose of the present invention is to provide a paint booth in which devices of actuation and movement of the sheets and/or of the devices for treatment of the products to be painted are simplified.
Not the least important purpose of the present invention is to provide a paint booth, and in particular a paint booth for automatic plants for painting products, which presents high reliability, and is relatively simple to produce at competitive costs.
This task, as well as the above and other purposes that will appear more clearly hereinafter, are achieved by a paint booth for plants for painting products that comprises: a supporting structure; one or more sheets, which define at least one portion of internal space of said booth; and means for surface treatment of said products. The booth according to the invention is characterized in that at least one of said sheets is mobile and has an opening through which said treatment means face within said portion of internal space. In addition, in the booth according to the invention at least one mobile sheet and/or at least one of said treatment means is connected to movement means that impart a reciprocating and simultaneous motion both on said mobile sheet and on said at least one treatment means.
For the purposes of the present invention, by the term “reciprocating motion” it is meant that the sheet and said treatment means are moved first in one direction and then in the opposite direction, traversing a certain stretch of the side surfaces of the internal space of the booth; by the term “simultaneous motion” it is meant that the sheet and said treatment means are moved in such way that their mutual position is always the same, i.e., in such a way that said treatment means is always in a position substantial corresponding to said opening of the sheet from which it faces the internal space of the booth.
Further characteristics and advantages of the present invention will emerge more clearly from the description of preferred, but non-exclusive, embodiments of a paint booth according to the invention, illustrated in the attached plate of drawings, in which:
The invention will be now described with reference to the annexed figures, in which the same reference numbers designate elements that are the same as one another, without wishing in any way to limit the sphere of application.
With reference to the figures referred to above, the paint booth according to the invention 1, 2, 3, 4, 5, 6, 7, 8 and 9 comprises a supporting structure constituted, for example, by a supporting framework. The booth further comprises one or more sheets, which define a portion of internal space 12, 22, 32, 42, 52, 62, 72, 82, 92 and 102 of the booth itself, and means 13, 23, 43, 53, 103, 631, 632, 731, 732, 931, 932 for surface treatment of said products.
The peculiarity of the booth according to the invention lies in the fact that at least one of said sheets 11, 21, 31, 41, 51, 61, 71, 81, 91 and 110 is mobile and has an opening 14, 24, 34, 44, 54, 641, 642, 104 and 106 through which said treatment means face within said portion of internal space. Said mobile sheet and/or at least one of the treatment means is connected to movement means 15, 25, 35, 45, 6575 and 95, which impart a reciprocating and simultaneous motion both on the mobile sheet and on said treatment means. The mobile sheet can be generally constituted by any material designed to define a portion of internal space of the booth, resistant to the treatments to which the products are subjected within said booth and sufficiently flexible to enable its bending or rolling and unrolling during movement thereof via said movement means. The opening 14, 24, 34, 44, 54, 641, 642, 104 and 106 can also be made in at least one rigid or semirigid longitudinal cross member.
The sheet and the treatment means can be connected to the movement means independently of one another. Actuation of the movement means, and consequent movement of the sheet and of the treatment means is in this case synchronized in such a way that said treatment means is always in said opening of the sheet from which it faces the internal space of the booth.
According to a preferred embodiment, said at least one sheet and at least one treatment means are connected to one another so as to guarantee mutual transmission of motion. In this case, the movement means can be connected to said sheet or else can be connected to said treatment means in such a way that, in the former case, the movement of the sheet will be transmitted to the treatment means and, in the latter case, the movement of the treatment means will be transmitted to the sheet.
With reference to
Alternatively (see
Another possible embodiment, described in
With reference to
Likewise, in the case where the booth requires the side and top walls and does not require a bottom wall, a possible embodiment, described in
The treatment means 13, 23, 43, 53, 103, 631, 632, 731, 732, 931 and 932 can be of various types, according to the type of product 100 to be treated and to the type of treatment which it is to undergo. For example, the treatment means can be formed by spray guns or else by powder-paint guns, or else by powder-paint blades, or in general by powder-paint ejection means, or else again by UV lamps or IR lamps. In the case where the treatment booth is constituted by an IR jellying oven or a UV cross-linking oven, the sheet may be constituted by a metal strip with reflecting surface (for example, chrome-plated or aluminium-plated) and also coated or shaped in such a way that it will present reliefs (for example, having a conical or pyramidal shape with a square or polygonal base), designed to maximize the refraction of the UV or IR radiation in all directions so as to enable it to reach every recess of the object to be treated thus enabling optimal jellying or cross-linking of its entire surface.
Except in the cases where the paint booth according to the invention is designed for use as UV or IR oven, it can moreover comprise means for cleaning the internal surface of said sheet 11, 21, 31, 41, 51, 61, 71, 81, 91, 110 and said internal space of the booth itself. For example, said cleaning means can be formed by one or more suction manifolds positioned longitudinally in the internal space of the booth. The suction manifold has preferably at least one slit, which extends in a longitudinal direction, an edge of said slit being substantially in contact with the internal surface of the sheet. Preferably, the suction manifold is positioned in at least one of the top or bottom ends of the internal space 12, 22, 32, 42, 52, 62, 72, 82, 92 and 102 of the booth.
An example of an embodiment of the booth according to the invention that envisages use of suction manifolds is illustrated in
The products to be treated 100 enter the internal space 62, for example hanging from an overhead conveyor 101, and undergo throughout their length the specific treatment for which the treatment means 631 and 632 are provided, for example a powder-paint treatment. This is made possible by the fact that the treatment means 631 and 632 move in a vertical direction and with a reciprocating motion during passage of the products 100 within the booth 6. The treatment means 631 and 632 are positioned in a substantially symmetrical way with respect to the transverse axis of the internal space of the booth, and their travel is adjusted in such a way that the entire surface of the product 100 will be treated.
In practice, as may be seen from
Said manifolds are arranged longitudinally in the internal space 62 of the booth 6, for example, at the bottom end of said internal space 62. In this way, the excess powder ejected by the guns is collected by the suction manifolds 661 and 662 and sent, for example, into purposely provided recovery cyclones (not illustrated in the figure). At the same time, since the guns 631 and 632 are positioned substantially on the outside of the space defined by the half-sheets 611 and 612, they are protected from any possible deposits of powder on them as well as on the corresponding accessory parts (cables, pipes, etc.).
A particular embodiment (not illustrated in the figures), envisages that the booth according to the invention will comprise first suction means set in a position corresponding to one or more openings of said mobile sheet 11, 21, 31, 41, 51, 61, 71, 81, 91 and 110, said first suction means moving simultaneously with said mobile sheet. In practice, in addition to the treatment means, the booth according to the invention can comprise suction means that face the internal space of the booth and move simultaneously to the treatment means and to the sheet so as to contribute to cleaning of the internal space of the booth and of the sheet itself. Said configuration can be applied in particular in the embodiment of booth provided in
The booth according to the invention can moreover comprise also second suction means positioned at the front and/or rear portion of said internal space. An embodiment of this type is illustrated in
The booth 7 further comprises second suction means formed, for example, by the suction manifolds 765, 766, 767 and 768 positioned vertically in the front and rear portion of the internal space 72. The suction manifolds 765, 766, 767 and 768 have a slit, which extends in a vertical direction in the proximity of the internal surface of the mobile sheet 71 and contribute to cleaning of the sheet 71 and of the internal space 72 of the booth. Both the horizontal manifolds 761, 762, 763, 764 and the vertical manifolds 765, 766, 767, 768 are appropriately connected to the cyclones 77 in which recovery of the powder sucked in occurs.
With reference to
Alternatively, with reference to
A particularly preferred embodiment envisages that the mobile sheet is substantially self-bearing. This can be made using a flexible material provided with a sufficient rigidity to obtain the mobile sheet. With reference to
The use of sheets made of materials that present a particularly high level of performance from the standpoint of elasticity may also enable self-bearing booths to be provided, which do not need any containment either for the thrusts outwards (e.g., rollers) or for the thrusts inwards (claws, rails, scrapers or brushes).
It may be seen how the paint booth according to the invention will enable the pre-set task and purposes to be fully achieved. Appropriate positioning of the treatment means at the openings of the mobile sheet enables said treatment means to be protected and their dirtying by the painting material to be prevented or minimized. At the same time, the movement of the sheet, combined with the presence and the appropriate positioning of cleaning means (suction means, scraper/brush or combinations of the two) enables effective removal of the residue of painting material from the sheets themselves and from the internal space of the booth.
Another important result that is achieved by the booth according to the present invention, is the optimization of the movement means of the mobile sheet and of the treatment means. Unlike booths of a known type that require at least two movement devices for moving separately the sheet and the treatment means, the booth according to the invention enables a mechanical connection with consequent transmission of motion between the mobile sheet and the treatment means. The result is that, as illustrated in some examples of embodiment of the booth according to the invention, it is sufficient to have a single moving device, which controls either the treatment means or the mobile sheet; in the former case, the mobile sheet will be driven in motion by the treatment means, whereas in the latter case the treatment means will be will be driven in motion by the mobile sheet. This enables reduction in the mechanical complexity of the booth and reduction in the costs of installation and maintenance of the booth itself and of the plant associated thereto.
Furthermore, according to a preferred embodiment, the mobile sheet can be provided so as to be substantially self-bearing, with consequent further constructional simplification and reduction in the installation costs.
The booth according to the present invention may be conveniently applied to plants for painting products. Plants for painting products, and in particular automatic painting plants that comprise one or more booths according to what has been described previously, constitute a further aspect of the present invention.
On the basis of the foregoing description, other characteristics, modifications or improvements are possible and evident to the average person skilled in the branch. Said characteristics, modifications and improvements are hence to be considered as forming part of the present invention. In practice, the materials used as well as the contingent dimensions and shapes, may be any whatsoever according to the requirements and the state of the art.
Number | Date | Country | Kind |
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BG 2005 A 000040 | Jul 2005 | IT | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/EP06/63816 | 7/3/2006 | WO | 00 | 1/29/2008 |