Apparatus for applying products, such as liquids and/or fluid mixes, to surfaces of manufactured articles

Abstract

 The apparatus for applying products such as liquids and/or fluid mixes on surfaces of manufactured articles (P) which advance on a conveyance line (4) comprises a frame (2) for supporting at least one tray (3) which is arranged above the line (4), is connected to a circuit for supplying the product to be applied, and has a spillway (5) for the outflow of the product onto the advancing manufactured articles (P), at least one motorized roller (8) having a longitudinal axis (9) which is substantially parallel to the plane defined by the line (4) and is arranged in an upward region proximate to the spillway (5) and is actuated so as to turn about the axis (9) in the opposite direction with respect to the product outflow direction, and a bottom (10) for collecting the excess product falling from the manufactured articles (P) which is arranged substantially below the line (4).

Description

[0001] The present invention relates to an apparatus for applying products, such as liquids and/or fluid mixes, to surfaces of manufactured articles.

[0002] Several methods are known for applying products constituted by liquids and/or fluid mixes to the exposed surface of manufactured articles; such methods differ according to the type of surface to be obtained.

[0003] In the ceramic sector, for example, the so-called film methods are known for applying products constituted by liquids and/or fluid mixes such as aqueous solutions and/or glazes.

[0004] These film methods are used to produce uniform, regular and smooth surfaces on manufactured articles made of ceramic, natural stone or the like, such as tiles advancing on conveyance lines, and use several devices, including slot-nozzle devices and bell-type devices.

[0005] Slot-nozzle devices are constituted by a hopper which is arranged above the manufactured articles advancing on the conveyance line; the outlet of said hopper lies transversely to said line and is closed by a nozzle in which there is provided a longitudinal slot with adjustable aperture.

[0006] A supply circuit introduces the product to be applied, e.g. glaze, into the hopper, from where such product falls, passing through said slot, in the form of a continuous film lying transversely to the advancement direction of the manufactured articles.

[0007] Bell-type devices are instead constituted by a sort of spherical dome which is arranged above the manufactured articles that advance along the conveyance line with its concavity directed downward: a central duct feeds from above the product to be applied, which flows over the convex outer surface of said dome.

[0008] The bell is further provided with means which adjust and direct the outflow of the product which falls from the edges of the dome in the form of one or two mutually opposite continuous films which lie transversely to the advancement direction of the manufactured articles.

[0009] A continuous layer of product is deposited on the exposed surface of the manufactured articles that pass through said films.

[0010] These conventional devices are not devoid of drawbacks, including the fact that they do not allow to apply products, such as liquids and/or fluid mixes, in layers of uniform thickness on the whole exposed surface of the manufactured articles and do not allow to obtain manufactured articles having smooth, uniform and regular surfaces.

[0011] The layers of applied products in fact have defects, such as scoring, undulations and/or delimited regions without product, clearly evident in the finished manufactured articles, which must therefore be classified as second-choice or rejected, with a consequent economic damage for the manufacturer.

[0012] It is noted that the causes of these defects include impurities, such as air bubbles, thickenings and/or clots, which form in the products to be applied and accumulate proximate to the slot of the slot nozzle, to the edges of the dome or to the supply duct of the bell: such impurities cause the profile of the falling film to be irregular and/or interrupt the continuity of said film, forming gaps therein.

[0013] Eliminating these impurities entails the intervention of operators who periodically clean by hand, during production and by using sponges, blades or the like, the slot and the edges of the dome or of the duct.

[0014] Alternatively, production is halted and the operators wash the entire apparatus.

[0015] Accordingly, the manufactured articles that advance during cleaning are damaged, production times are slowed down, and costs are incurred for the labor used.

[0016] The aim of the present invention is to eliminate the above-noted drawbacks of conventional devices by providing an apparatus for applying products such as liquids and/or fluid mixes on surfaces of manufactured articles which allows to apply the products in layers of uniform thickness, without producing accumulations at the center or at the edges of the surfaces of the manufactured articles on which they are deposited, and allows to obtain surfaces which are uniform, even, smooth and free from defects such as scoring or undulations, with a consequent increase in the aesthetic quality of said manufactured articles and a reduction in second-choice articles and rejects.

[0017] An object of the present invention is to limit operator interventions, reducing labor costs and ensuring a continuous production of high and constant quality.

[0018] Within the scope of this aim, a further object of the present invention is to provide an apparatus which is simple, relatively easy to provide in practice, safe in use, effective in operation and relatively low in cost.

[0019] This aim and these and other objects which will become better apparent are achieved by the present apparatus for applying products such as liquids and/or fluid mixes on surfaces of manufactured articles which advance on a conveyance line, characterized in that it comprises: a frame for supporting at least one tray which is arranged above said line, is connected to a circuit for supplying the product to be applied, and has a spillway for the outflow of said product onto the advancing manufactured articles; at least one motorized roller having a longitudinal axis which is substantially parallel to the plane defined by said line and is arranged in an upward region proximate to said spillway and is actuated so as to turn about said axis in the opposite direction with respect to the product outflow direction; and a bottom for collecting the excess product that falls from said manufactured articles, said bottom being arranged substantially below said line.

[0020] Further characteristics and advantages of the present invention will become better apparent from the detailed description of a preferred but not exclusive embodiment of an apparatus for applying products, such as liquids and/or fluid mixes on surfaces of manufactured articles, illustrated only by way of non-limitative example in the accompanying drawings, wherein:

Figure 1 is a perspective view of an apparatus according to the invention;

Figure 2 is a schematic side sectional view of a portion of the apparatus of Figure 1;

Figure 3 is a schematic top view of a portion of the apparatus of Figure 1.

[0021] With reference to the figures, 1 generally designates an apparatus for applying products such as liquids and/or fluid mixes on surfaces of manufactured articles.

[0022] In the ceramics sector, for example, the manufactured articles can be constituted by tiles P or the like and can be made of ceramic material, natural stone or the like.

[0023] The apparatus 1 comprises a frame 2 for supporting a tray 3 being arranged above a line 4 for conveying the tiles P which is connected to a circuit for supplying the product to be applied; said tray has a spillway 5 which draws from the filling level of said tray 3 and from which the product flows out, pouring onto the advancing tiles P.

[0024] The product to be applied is of the liquid and/or fluid mix type, such as for example ceramic glazes and/or aqueous solutions of coloring salts.

[0025] The line 4 is of the type with belts 6 which are closed in a loop and are wound around pulleys and/or drums 7; the product supply circuit instead is not shown, since it is of a conventional type.

[0026] The apparatus 1 further comprises a motorized roller 8, which is arranged proximate to and above the spillway 5 so that its own longitudinal axis 9 is substantially parallel to the plane traced by the line 4, and a bottom 10 for collecting the excess product which falls from the tiles P, said bottom being arranged substantially below the line 4.

[0027] The roller 8 is rotatably supported by a supporting profiled element 11 which is associated with the frame 2 and is rotatably actuated about its own axis 9 by the motor 12 in the opposite direction with respect to the product outflow direction; the roller 8 therefore contrasts the advancement of the product.

[0028] The tray 3 is constituted by an upper basin 13 and a lower basin 14 which are arranged one after the other and are connected one another by an inclined plane 15.

[0029] The upper basin 13 is associated with the product supply circuit by means of one or more ports 16 formed in its bottom and is provided with an overflow 17 which pours the fed product onto the inclined plane 15.

[0030] The lower basin 14 is fed with the product flowing on the inclined plane 15 and from there the product is poured onto the tiles P through the spillway 5, being formed at the outer edge of the lower basin 14 which is directed towards the line 4.

[0031] Conveniently, the surface of the inclined plane 15 on which the product flows is undulated and/or provided with such uneven regions as to facilitate the mixing and homogenization of said product; the shape of the tray 3 therefore allows to homogenize the falling product.

[0032] The spillway 5 is constituted by a lip 18 folded with a substantially convex profile and whose longitudinal extension lies substantially transversely to the line 4: the outflowing product thus falls as a continuous film.

[0033] The roller 8 is arranged above the lip 18, substantially in contact with the free surface of the outflowing product, and so that its axis 9 is oblique with respect to the spillway 5 and to the line 4.

[0034] The spillway 5 and the roller 8 are both longer than the dimension of the tiles P at right angles to the line 4, while the roller 8 is advantageously shorter than the spillway 5.

[0035] The apparatus 1 further comprises means 19 for adjusting the height of the roller 8 with respect to the spillway 5; the control handwheels 20 of said means have been illustrated schematically, since they are in any case of a conventional type, and allow to position the roller 8 at different heights with respect to the spillway 5, thus allowing to determine the thickness of the falling film.

[0036] The roller 8, by rotating in the opposite direction with respect to the product outflow direction, performs two functions: determining and evening out the thickness of the film that falls onto the tiles P, and retaining and removing the impurities present in the product upstream of the spillway 5, thus preventing them from falling onto the tiles P.

[0037] It is in fact noted that any impurities present in the product, such as for example clots and/or air bubbles, rise to its surface and are retained upstream of the spillway 5 by the roller 8, against which they accumulate; the oblique arrangement of the axis 9 allows to transfer the accumulated impurities towards the end of the roller 8 which is arranged substantially downstream of the spillway 5.

[0038] In this manner, thanks to the relative dimensions of the roller 8, of the spillway 5 and of the tiles P, the product falling outside the tiles P at the downstream end of the roller 8 entrains with it the impurities, which are discharged into the bottom 10, which is provided with an outlet 21.

[0039] Conveniently, the apparatus 1 is provided with means for cleaning the roller 8 being constituted by a doctor 22 which can be orientated, is supported by a bar 23 associated with the profiled element 11 and is provided with means 24 for varying its inclination with respect to the roller 8; the doctor 22 is tangent to the outer surface of said roller 8, from which it scrapes and eliminate the product and the impurities that adhere to it.

[0040] Alternatively, the doctor 22 can be arranged at a predefined distance from the outer surface of the roller 8, so that a continuous layer of product is formed on said surface, its thickness depending on the physical and rheological characteristics of the product, which facilitates an even and uniform distribution of the product falling onto the surface of the tiles P.

[0041] Finally, the apparatus 1 comprises means 25 for adjusting its height and means 26 for adjusting the inclination of the tray 3 with respect to the plane formed by the line 4.

[0042] The means 25 for adjusting the height of the tray 3 are constituted by two substantially vertical columns 27 which are fixed to the frame 2 at the mutually opposite sides 28 of the tray 3; each column is slidingly coupled to a respective tab 29 which is formed at the sides 28 and is provided with fixing means 30 and actuation means 31.

[0043] The inclination adjustment means 26 are constituted by two pivots 32 which are substantially parallel to the plane traced by the line 4, are perpendicular thereto, are associated with the frame 2 and are mutually coaxial.

[0044] Each pivot 32 is rotationally coupled respectively to one of the sides 28 of the tray 3 by way of flanges 33 which are provided with means 34 for locking said rotation.

[0045] It is thus possible to adjust the position of the tray 3 according to the physical characteristics and outflow speed of the product.

[0046] In practice it has been observed that the above-described invention achieves the intended aim and objects, i.e. to apply products such as liquids and/or fluid mixes, such as aqueous solutions or ceramic glazes, to the exposed surface of manufactured articles, such as tiles, in uniform layers which are devoid of impurities, scoring, undulations and/or air bubbles, obtaining smooth and uniform surfaces.

[0047] The invention thus conceived is susceptible of numerous modifications and variations, all of which are within the scope of the appended claims.

[0048] All the details may further be replaced with other technically equivalent ones.

[0049] In practice, the materials used, as well as the shapes and the dimensions, may be any according to requirements without thereby abandoning the scope of the protection of the appended claims.

[0050] The disclosures in Italian Patent Application No. MO2000A000068 from which this application claims priority are incorporated herein by reference.

[0051] Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly, such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.

Claims

1. An apparatus for applying products such as liquids and/or fluid mixes on surfaces of manufactured articles (P) which advance on a conveyance line (4), characterized in that it comprises a frame (2) for supporting at least one tray (3) which is arranged above said line (4), is connected to a circuit for supplying the product to be applied, and has a spillway (5) for the outflow of said product onto the advancing manufactured articles (P), at least one motorized roller (8) having a longitudinal axis (9) which is substantially parallel to the plane defined by said line (4) and is arranged in an upward region proximate to said spillway (5) and is actuated so as to turn about said axis (9) in the opposite direction with respect to the product outflow direction, and a bottom (10) for collecting the excess product that falls from said manufactured articles (P), said bottom (10) being arranged substantially below said line (4).

2. The apparatus according to claim 1, characterized in that said tray (3) is constituted by at least one upper basin (13) and one lower basin (14) which are arranged one after the other and are mutually connected by an inclined plane (15), said upper basin (13) being associated with said supply circuit and being provided with an overflow (17) which is adapted to pour the product onto said inclined plane (15), said spillway (5) being formed at the outer edge of said lower basin (14).

3. The apparatus according to one or more of the preceding claims, characterized in that said inclined plane (15) has an undulated surface.

4. The apparatus according to one or more of the preceding claims, characterized in that said spillway (5) is constituted by a folded lip (18) which has a substantially convex profile and a longitudinal extension lying substantially transversely to said line (4).

5. The apparatus according to one or more of the preceding claims, characterized in that said roller (8) is arranged so that its longitudinal axis (9) is substantially oblique with respect to said spillway (5).

6. The apparatus according to one or more of the preceding claims, characterized in that the extension of said spillway (5) is substantially greater than the dimension of the manufactured articles (P) lying transversely to said line (4).

7. The apparatus according to one or more of the preceding claims, characterized in that the extension of said roller (8) is substantially greater than the dimension of the manufactured articles (P) lying transversely to said line (4).

8. The apparatus according to one or more of the preceding claims, characterized in that the extension of said roller (8) is substantially smaller than the extension of said spillway (5).

9. The apparatus according to one or more of the preceding claims, characterized in that it comprises means (25) for adjusting the height of said tray (3) with respect to the plane traced by said line (4).

10. The apparatus according to one or more of the preceding claims, characterized in that it comprises means (26) for adjusting the inclination of said tray (3) with respect to the plane traced by said line (4).

11. The apparatus according to one or more of the preceding claims, characterized in that it comprises means (19) for adjusting the height of said roller (8) with respect to said spillway (5).

12. The apparatus according to one or more of the preceding claims, characterized in that it comprises means (22) for cleaning said roller (8) which are adapted to eliminate the accumulated product from its surface.

13. The apparatus according to one or more of the preceding claims, characterized in that said means (25) for adjusting the height of said tray (3) are constituted by two substantially vertical columns (27) which are fixed to said frame (2) at the mutually opposite sides of the tray (3), each column (27) being slidingly coupled to a respective tab (29) formed in said sides (28) and provided with fixing means (30).

14. The apparatus according to one or more of the preceding claims,
characterized in that said means (26) for adjusting the inclination of said tray (3) are constituted by two pivots (32) which are substantially parallel to said plane, are associated with said frame (2), are mutually coaxial, and are each rotationally coupled respectively to one of said sides (28) of the tray (3), said sides (28) being provided with rotation locking means (34).

15. The apparatus according to one or more of the preceding claims, characterized in that said cleaning means are constituted by a doctor (22) which can be orientated and is tangent to the outer surface of said roller (8).

Drawing