SYSTEM FOR APPLYING A PRODUCT BY ROLLER

Abstract

A system for applying a product (3) by roller is disclosed. The system has an applicator roller (1) for applying a product (3) on a substrate (4) and a first dosing roller (2) for dosing said product (3) on the surface of the applicator roller (1), wherein the system comprises at least one second dosing roller (2) configured to fine-tune the dosing performed by the first dosing roller (2), thereby adjusting the amount of product (3) dosed on the surface of the applicator roller (1).

Claims

1. A system for applying a product (3) by roller comprising an applicator roller (1) for applying a product (3) on a substrate (4) and a first dosing roller (2) for dosing said product (3) on the surface of the applicator roller (1), at least one second dosing roller (2) configured to fine-tune the dosing performed by the first dosing roller (2), thereby adjusting the amount of product (3) dosed on the surface of the applicator roller (1).

2. The system for applying a product (3) by roller according to claim 1, further comprising a movement subsystem, which enables the first dosing roller (2) and/or the second dosing roller (2) to move closer to and/or farther away from the applicator roller (1).

3. The system for applying a product (3) by roller according to claim 1, further comprising an independent motor for the applicator roller (1), for the first dosing roller (2) and for the at least one second dosing roller (2).

4. The system for applying a product (3) by roller according to claim 3, further comprising a regulation subsystem for the direction and the rotation speed of the first dosing roller (2) and of the at least one second dosing roller (2).

5. The system for applying a product (3) by roller according to claim 1 further comprising at least one dosing body (6), wherein the at least one dosing body (6) comprises the first dosing roller (2) and/or the at least one second dosing roller (2), wherein the dosing body (6) comprises one or more side walls (7), wherein the dosing body (6) defines, together with the applicator roller (1), a first product (3) collection chamber (9).

6. The system for applying a product (3) by roller according to claim 5, wherein the at least one dosing body (6) defines, together with the applicator roller (1), at least one second product (3) collection chamber (9).

7. The system for applying a product (3) by roller according to claim 5, further comprising a product (3) recirculation circuit, configured to recirculate the product (3) from the first product (3) collection chamber (9) and/or from the at least one second product (3) collection chamber (9).

8. The system for applying a product (3) by roller according to claim 5, further comprising product (3) level maintenance means in the first product (3) collection chamber (9) and/or in the at least one second product (3) collection chamber (9), in order to maintain a constant level of product (3) due to the extraction or introduction of product (3) into said chambers (9), (9).

9. The system for applying a product (3) by roller according to claim 5, wherein the first product (3) collection chamber (9) comprises an opening (13) defined by at least one side wall (7) of the dosing body (6) and by the applicator roller (1), wherein said opening (13) has a width such as to enable the passage towards the first product (3) collection chamber (9) of a layer of product (3) which has not been deposited on the substrate (4) and which returns adhered to the applicator roller (1).

10. The system for applying a product (3) by roller according to claim 5, wherein the at least one dosing body (6) comprises a product (3) collection tray (12) located underneath the first product (3) collection chamber (9) and/or underneath the at least one second product (3) collection chamber (9), wherein said product (3) collection tray (12) defines, together with the applicator roller (1) and/or together with at least one side wall (7) of the dosing body (6), a product (3) accumulation compartment (11), for accumulating product (3) dragged by the first dosing roller (2) and/or by the second dosing roller (2) and/or detached from the applicator roller (1).

11. The system for applying a product (3) by roller according to claim 5, further comprising at least one retainer (5) configured to retain and/or scrape product (3) dragged by the first dosing roller (2) and/or by the second dosing roller (2).

12. A method for applying a product (3) by roller comprising using the system for applying a product (3) by roller according to claim 1, comprising moving the first dosing roller (2) and/or the at least one second dosing roller (2) closer and/or farther away from the applicator roller (1), in order to reduce and/or increase, respectively, the amount of product (3) to be dosed on the surface of the applicator roller (1).

13. The method for applying a product (3) by roller according to claim 12, further comprising setting an angular speed for the first dosing roller (2) and/or at least one second dosing roller (2), such that if said angular speed has the same direction as the angular speed of the applicator roller (1), the amount of product (3) dosed on the surface of the applicator roller (1) decreases, and; if said angular speed has the direction inverse to the angular speed of the applicator roller (1), the amount of product (3) dosed on the surface of the applicator roller (1) increases.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0070] The following figures have been included as part of the description of at least one embodiment of the invention.

[0071] FIG. 1 shows a schematic representation of a conventional system for applying a product by roller.

[0072] FIG. 2 shows a schematic representation of a first embodiment of the present invention, wherein the system for applying a product by roller comprises a dosing body with a first product collection chamber, a first dosing roller, a second product collection chamber, a second dosing roller and a product collection tray.

[0073] FIG. 3 shows a schematic representation of a second embodiment of the present invention, wherein the system for applying a product by roller comprises two product collection chambers, a first dosing roller and a second dosing roller.

[0074] FIG. 4 shows a schematic representation of a third embodiment of the present invention, with a first dosing roller, a second dosing roller, and a blade or spike for scraping product dragged by the second dosing roller.

[0075] FIG. 5a shows a representation of a side view of the application of a product to a series of substrates which run on a conveyor belt.

[0076] FIG. 5b shows a representation of a top view corresponding to FIG. 5a.

[0077] FIG. 6a shows a schematic representation of a variant embodiment of the present invention, wherein the dosing body incorporates a support element for the dosing roller.

[0078] FIG. 6b shows the enlarged A-A cut of the schematic representation of FIG. 6a in order to better see the support element.

DETAILED DESCRIPTION

[0079] The present invention relates, as mentioned above, to a system for applying a product (3) by roller.

[0080] FIG. 1 shows a system for applying a product (3) by roller corresponding to the state of the art. An applicator roller (1) for applying a product (3) on a substrate (4) can be seen. A dosing roller (2) is also seen, for dosing or applying product (3) on the applicator roller (1). The figure shows a blade (5) which provides a scraping of the dosing roller (2) when it rotates in the counterclockwise direction during the operation thereof and a retention of the product (3), making said product (3) once again available for dosing or returning it to a recirculation circuit (not shown in the figures).

[0081] The system for applying a product (3) by roller object of the present invention comprises (like in conventional systems) an applicator roller (1) for applying a product (3) on a substrate (4) and a first dosing roller (2).

[0082] Said applicator roller (1) preferably comprises a rubber surface (8).

[0083] According to the present invention, the system for applying a product (3) by roller comprises at least one second dosing roller (2). By means of the first dosing roller (2) an initial (or thick) dosage of product (3) is achieved on the applicator roller (1). By means of the second dosing roller (2), the dosing of product (3) on the applicator roller (1) is able to be fine-tuned, adjusting the amount and/or thickness of the layer of product (3) dosed on the applicator roller (1) to a predefined value.

[0084] Each dosing roller (2, 2) preferably comprises a metal surface, typically made of chromed steel.

[0085] Said at least two dosing rollers (2, 2) can make up part of a single dosing body (6), or can be independent dosing bodies (6).

[0086] Optionally, each dosing body (6) can comprise one or more side walls (7).

[0087] Each dosing body (6) can define, together with the applicator roller (1), at least one product (3) collection chamber (9), (9). Said at least one product (3) collection chamber (9), (9) is used for collecting and recirculating said product (3) towards a pump, for pumping and new dosing on the applicator roller (1) and/or the collection chamber(s) (9), (9).

[0088] According to a first embodiment of the present invention, shown in FIG. 2, there is a single dosing body (6) comprising a first dosing roller (2) and a second dosing roller (2). In this embodiment, the dosing body (6) comprises several side walls (7). The dosing body (6) defines, together with the applicator roller (1), a first product (3) collection chamber (9) and a second product collection chamber (9), for receiving product (3) coming from the pump and for recirculating said product (3) towards the pump, for new circulation towards the product (3) collection chambers (9, 9). More specifically, in this first embodiment, the first product (3) collection chamber (9) is defined by the first dosing roller (2), at least one side wall (7) of the dosing body (6) and the applicator roller (1); the second product (3) collection chamber (9) is defined by the second dosing roller (2), at least one side wall (7) of the dosing body (6), the first dosing roller (2) and the applicator roller (1).

[0089] According to the embodiment shown in FIG. 2, a retainer (5) is arranged in a joint area between the dosing roller (2, 2) and the dosing body (6), both in the upper portion and in the lower portion of the dosing roller (2, 2), providing the function of retaining and/or scraping product (3) adhered to the dosing rollers (2, 2).

[0090] FIG. 3 shows a second embodiment of the system for applying a product (3) by roller, object of the present invention, wherein a first dosing body (6) comprises a first dosing roller (2) and at least one side wall (7). Said first dosing body (6) defines, together with the applicator roller (1), a first product (3) collection chamber (9). The product (3) dosed by the first dosing roller (2) from the first product (3) collection chamber (9) is directed, by the surface of the applicator roller (1), towards the second dosing roller (2) (which forms, by itself, a second dosing body (6)). In this embodiment, the system for applying a product (3) by roller comprises a collection module (10) equipped with retainers (5); said product collection module (10) defines, together with the second dosing roller (2), a second product (3) collection chamber (9), for accumulating excess product (3) from the dosage, dragged by the second dosing roller (2). The second product collection chamber (9) has an outlet which is directed towards the recirculation circuit. As seen, the embodiment shown in FIG. 3 differs from the embodiment shown in FIG. 2 in the arrangement of the second product collection chamber (9).

[0091] According to the embodiment shown in FIG. 3, a retainer (5) is arranged in a joint area between the dosing roller (2) and the dosing body (6), both in an upper area and in a lower area, providing the function of retaining and/or scraping product (3) adhered to the dosing roller (2). Likewise, the collection module (10) incorporates a retainer (5) in the lower portion thereof.

[0092] FIG. 4 shows a third embodiment of the system for applying a product (3) by roller, object of the present invention. In this embodiment, which is simpler than the previous ones, there is a first dosing roller (2) and a second dosing roller (2). Each dosing roller (2, 2) constitutes, by itself, an independent dosing body (6). There is a spike or blade (5) for scraping the excess product (3) dragged by the second dosing roller (2), which has not been dosed on the applicator roller (1).

[0093] Preferably, each product (3) collection chamber (9), (9) is closed on the side by means of closing seals or side sealing plates (not shown in the figures) against the very sides of the applicator roller (1), thereby guaranteeing that there is no product (3) lost which comes out of the product (3) collection chambers (9), (9).

[0094] In any of the embodiments, there is a pumping circuit which is directed from a pump towards the first product (3) collection chamber (9) and/or towards the second product (3) collection chamber (9) and/or towards the surface of the applicator roller (1). Neither the pumping circuit nor the pump are represented in the figures.

[0095] When the product (3) arrives from the pumping circuit to the first product (3) collection chamber (9) and/or to the second product (3) collection chamber (9) and/or to the surface of the applicator roller (1), the product (3) is dosed by the corresponding dosing roller (2, 2) on the applicator roller (1).

[0096] In those embodiments wherein there is at least one product (3) collection chamber (9), (9), the first product (3) collection chamber (9) and, if appropriate, the second product (3) collection chamber (9), comprise valves (not shown in the figures) for the passage of product (3) towards the recirculation circuit (not shown in the figures) which is directed towards the pump and once again towards the pumping circuit. For the opening of the valve of the first chamber (9) and/or of the second chamber (9), there is a level sensor (not shown in the figures) in each chamber (9), (9), such that when a predetermined product (3) level is reached in each of said chambers (9), (9), the valve is opened to recirculate the product (3), until the level of product (3) in each of said chambers (9), (9) falls once again below said predetermined level. In an alternative or complementary manner, the product (3) collection chamber(s) (9), (9) can have an overflow (not shown) with an overflow opening for the product (3) arranged in a side wall of the corresponding collection chamber (9), (9).

[0097] As shown in FIG. 2, the dosing body (6) can comprise a product (3) collection tray (12). Said collection tray (12) defines, together with at least one side wall (7) of the dosing body (6) and together with the applicator roller (1), a product (3) accumulation compartment (11), for accumulating product (3) dragged by the second dosing roller (2) and/or detached from the applicator roller (1).

[0098] The area of the dosing body (6) located in correspondence with the bottom of the product (3) collection tray (12) comprises a drain (not shown in FIG. 2) for removing product (3) towards a waste duct or towards the recirculation circuit. This drain of the collection tray (12) facilitates the cleaning of the accumulation compartment (11).

[0099] The product collection tray (12) facilitates the cleaning of the application system by means of a cleaning product supplied to the application system instead of the application product (3). For cleaning, the cleaning product crosses through the first dosing roller (2) and/or the second dosing roller (2), dragging the excess application product (3) along with the cleaning product to the accumulation compartment (11), wherein said products accumulate and from where they can be removed by means of a drain. The cleaning can be performed by means of the combination of pumping cleaning product with different arrangements of the accumulation compartment (11) and rotations of the dosing rollers (2, 2). For the cleaning, the rotation of the dosing roller (2) can be performed in the clockwise direction.

[0100] According to a possible embodiment, the first product (3) collection chamber (9) comprises an opening (13), defined by at least one side wall (7) of the dosing body (6) and the applicator roller (1). Said opening (13) is wide enough to enable the passage of the product (3) which has not been deposited on the substrate (4) and which returns adhered to the applicator roller (1), once again towards the first product (3) chamber (9).

[0101] It is possible that, after applying/dosing the product (3) on the applicator roller (1), said product (3) does not adhere to the substrate (4) (see FIG. 5a and FIG. 5b), either due to it being applied on an area of the conveyor belt corresponding to an intermediate space (14) between two consecutive substrates (4), or due to it being applied on an area of the conveyor belt corresponding to a side space (15) to the right and/or left of the substrate (4), outside of the substrate (4).

[0102] Preferably, the system for applying a product (3) by roller, object of the present invention, comprises a movement subsystem, which enables the first dosing roller (2) and/or the second dosing roller (2) to move closer to and/or farther away from the applicator roller (1). This can be done by moving the dosing body or bodies (6) closer to/farther away from each other respectively towards the applicator roller (1) or in the direction opposite from the applicator roller (1). It can also be achieved by making the dosing body or bodies (6) pivot with respect to the applicator roller (1).

[0103] Also preferably, the system for applying a product (3) by roller comprises a motor of the first dosing roller (2) and/or of the second dosing roller (2) which is/are independent from the motor of the applicator roller (1).

[0104] By controlling the distance of the first dosing roller (2) and/or of the second dosing roller (2) with respect to the applicator roller (1), the thickness of the layer of product (3) to be dosed on the applicator roller (1) and, therefore, the gram mage of the layer of product (3) to be applied on the substrate (4) can be determined. The greater the distance between the dosing roller (2, 2) and the applicator roller (1), the greater the amount of product (3) dosed.

[0105] However, in the first embodiment shown in FIG. 2, if the distance between the first dosing roller (2) and the applicator roller (1) increases above a threshold value, product (3) ceases to be dosed, and the product (3) that could be dragged by the first dosing roller (2) towards the outside of the first chamber (9) falls in the second chamber (9) or in the collection tray (12). Likewise, if the distance between the second dosing roller (2) and the applicator roller (1) increases above a threshold value, product (3) ceases to be dosed, and the product (3) that could be dragged by the second dosing roller (2) towards the inside of the second chamber (9).

[0106] Additionally, by controlling the speed of the first dosing roller (2) and/or of the second dosing roller (2), the amount of product (3) to be dosed on the applicator roller (1) and, therefore, the amount of product (3) to be applied on the substrate (4) can also be controlled.

[0107] When the direction of the linear speed of the first dosing roller (2) and/or of the second dosing roller (2) coincides with the direction of the linear speed of the applicator roller (1) in the area wherein said first dosing roller (2) and/or second dosing roller (2) is/are closer to the applicator roller (1) (i.e., when the angular speed(s) of the first dosing roller (2) and/or of the second dosing roller (2) has/have a direction opposite from the angular speed of the applicator roller (1)), the dosing of product (3) on the applicator roller (1) is favoured. In this situation, as already mentioned above, when the magnitude of the speed of the first dosing roller (2) and/or of the second dosing roller (2) increases, the amount of product (3) dosed on the applicator roller (1) increases.

[0108] Referring to FIGS. 2 to 4, in order to reduce the amount of product (3) applied, i.e. the grammage thereof, and therefore in order to remove product from the applicator roller (1), the dosing rollers (2, 2) rotate in the counterclockwise direction. In this manner, the dosing roller (2) provides the additional reduction of the amount of the product (3) applied on the substrate (4) according to the invention.

[0109] Also, as shown in FIG. 2, if the product (3) dosed by the second dosing roller (2) is excessive, a portion of the product (3) can fall into the collection tray (12); moreover, it is possible for a portion of the product (3) dosed excessively by the second dosing roller (2) to stay adhered to the second dosing roller (2). In this case, a retainer (5) located beneath the second dosing roller (2), and in a position flush with the second dosing roller (2), scrapes or lifts said excess product (3), causing this excess product (3) to fall into the collection tray (12).

[0110] Moreover, when the direction of the linear speed of the first dosing roller (2) and/or of the second dosing roller (2) is opposite from the direction of the linear speed of the applicator roller (1) in the area wherein said first dosing roller (2) and/or second dosing roller (2) is/are closer to the applicator roller (1) (i.e., when the angular speed(s) of the first dosing roller (2) and/or of the second dosing roller (2) has/have the same direction as the angular speed of the applicator roller (1)), the dosing of product (3) on the applicator roller (1) is blocked or hindered. In this situation, as already mentioned above, when the magnitude of the speed of the first dosing roller (2) and/or of the second dosing roller (2) increases, the amount of product (3) dosed on the applicator roller (1) decreases.

[0111] According to one advantage of the invention, it is possible to make the dosing rollers (2, 2) of the invention with a reduced diameter with respect to conventional dosing rollers (2), which enables a dosing body (6) having smaller dimensions and a more compact system to be obtained. This reduced size can lead to a reduction in the flexural rigidity of the dosing roller (2), (2) and of the dosing body (6) as a consequence of the lower inertia of the dosing roller (2), (2), which may cause bending or deformations in the dosing roller (2), (2) which tends to separate the dosing roller (2), (2) from the applicator roller (1) during the operation of the system when, for example, the dosing roller (2), (2) is arranged supported on both ends thereof against the dosing body (6). A bending of the dosing roller (2), (2) would lead to the problem of an incorrect dosing of the product (3).

[0112] In order to solve this problem, as seen in FIGS. 6a and 6b, in an embodiment according to the invention, it is foreseen that the dosing body (6) comprises a support element (16) for the dosing roller (2), (2), which extends at least partially along the length of the dosing roller (2), (2), enabling the bending or deformation of the dosing roller (2), (2) against the dosing body (6) to be compensated for. This support element (16) retains the dosing roller (2), (2) in the dosing position thereof, forcing the contact of the dosing roller (2), (2) with the applicator roller (1) during the operation of the system. In the variant embodiment shown in FIGS. 6a and 6b, the support element (16) is formed by an expandable or inflatable rubber, such that when the support element (16) is expanded or inflated, it retains the dosing roller (2), (2) against the applicator roller (1) during the operation of the system. As shown in FIG. 6b, a sliding element (17) can be arranged between the support element (16) and the dosing roller (2), (2) in order to prevent friction between the support element (16) and the dosing roller (2), (2).