This application claims benefit of Italian patent application number 102017000130571, filed Nov. 15, 2017 which is herein incorporated by reference.
The present invention relates in general to textile printers for digital printing on fabrics.
More particularly, the invention relates to a unit for thermosetting the colors (inks) onto the fabrics.
In digital printing on fabrics, thermosetting of the inks on the fabric may be necessary. In these cases, it is common to use a thermosetting unit comprising a heated roller, rotatable about a rotation axis and having a cylindrical outer surface on which the moving fabric is wound with a predetermined winding angle. The thermosetting unit can be integrated into the textile printer (in-line thermosetting) or it can be a stand-alone unit separate from the textile printer. The working temperature on the outer surface of the heated roller in contact with the fabric can be between 100-200° C. Heating of the heated roller can be obtained by means of diathermic oil circulating inside the heated roller in contact with the outer surface, or by means of an infrared lamp located inside the heated roller.
The fabric for thermosetting almost completely wraps the outer surface of the heated roller and moves at a speed equal to the peripheral speed of the heated roller.
In solutions according to the prior art, the contact angle between the fabric and the heated roller is fixed. To improve the quality of the thermosetting process, especially in the case of in-line thermosetting (printing on textile support and immediate thermosetting), it would be desirable to provide a system that allows varying of the winding angle of the fabric on the heated roller, for example as a function of printing speed, print resolution, type of material used, operating temperature, inks used, etc.
The document JP 3 810852 B2 describes a unit comprising a heated roller rotating about a rotation axis, and a fabric guiding device comprising two rollers which guide the fabric in contact with the outer surface of the heated roller, wherein the rollers of the guiding device are movable to adjust the winding angle of the fabric around the heated roller.
The present invention aims to provide a unit for thermosetting printed fabrics which enables the aforementioned requirement to be satisfied.
According to the present invention, this object is achieved by a thermosetting unit having the characteristics described herein.
The claims form an integral part of the disclosure provided here in relation to the invention.
The present invention will now be described in detail with reference to the attached drawings, given purely by way of non-limiting example, wherein:
It will be appreciated that, for clarity and simplicity of illustration, the various figures may not be reproduced on the same scale.
With reference to
The thermosetting unit 10 comprises a stationary supporting structure 12 including two sides 14 formed by two vertical walls parallel to each other.
The thermosetting unit 10 comprises a heated roller 16 having a cylindrical outer surface and carried in a rotatable manner about a rotation axis A by two side supports 18 fixed to the sides 14 of the stationary supporting structure 12. The heated roller 16 is rotated about the axis A by means of an electric motor 20 which can be carried by one of the sides 14 of the stationary supporting structure 12 (
With reference in particular to
With reference to
With reference to
The adjusting device 40 comprises a shaft 46 parallel to the rotation axis A, rotatably carried by the sides 14 of the stationary supporting structure 12. The shaft 46 is rotatable about its own axis and is in a fixed position with respect to the stationary supporting structure 12. Two toothed sprockets 48 are fixed on the shaft 46, which engage with the respective gears 42. The shaft 46 is rotated about its axis by a motor 50 carried by one of the sides 14 of the stationary supporting structure 12. The motor 50 controls the joint rotation of the two gears 42 about the axis A. Thus, the motor 50 can adjust the angular position of the first guiding device 22 about the heated roller 16.
With reference to
The thermosetting unit according to the present invention allows variation of the contact angle α of the fabric 86 with the heated outer surface of the heated roller 16. Adjusting the contact angle allows the contact time between the fabric and the heated roller to be varied. Therefore, a different contact time can be set according to the type of fabric (elastic, light, or heavy, of different weft and warp, fabric or non-woven fabric or of different weights).
Adjusting the contact angle α is obtained by adjusting the angular position of the first guiding element 22 about the axis A by means of the adjusting device 40. The contact angle α can be adjusted according to operating parameters such as: print speed, print resolution, type of fabric, operating temperature, inks used, etc.
The possibility of adjusting the contact time between the fabric and the outer surface of the heated roller 16 allows improvement of the quality of the thermosetting process, especially in the case where the thermosetting is carried out immediately after the printing step as in the case of a thermosetting unit arranged in-line with the textile printer.
When the printing or movement of the fabric stops (for example, for a cleaning operation, due to an error, while waiting for a subsequent print, or due to an emergency), it is possible to detach the fabric from contact with the heated roller to prevent any thermosetting defects. When the problem that caused the printer to stop is resolved, the adjusting device automatically returns the fabric so that it is in contact with the heated roller at the set winding angle.
The solution according to the present invention also allows suction of the fumes formed during the thermosetting process. Suction of the fumes takes place inside the guiding elements 22, 24 and does not require other elements for extracting the fumes.
Furthermore, the solution according to the invention allows simplification and speeding up of the insertion operations of the fabric.
Of course, without prejudice to the principle of the invention, the details of construction and the embodiments may be widely varied with respect to those described and illustrated, without thereby departing from the scope of the invention as defined by the claims that follow.
Number | Date | Country | Kind |
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102017000130571 | Nov 2017 | IT | national |
Number | Name | Date | Kind |
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20090322824 | Hori | Dec 2009 | A1 |
20160070227 | Wada | Mar 2016 | A1 |
20190143718 | Martellono | May 2019 | A1 |
Number | Date | Country |
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0464616 | Jan 1992 | EP |
08002760 | Jan 1996 | JP |
H082760 | Jan 1996 | JP |
3810852 | Aug 2006 | JP |
Entry |
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Italian Search Report and Written Opinion dated Jul. 5, 2018 for Application No. IT201700130571. |
Number | Date | Country | |
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20190144228 A1 | May 2019 | US |