Patent Application
20240025195
The object of the present invention, as stated in its title, is a glass-printing machine with continuous transportation of the glass comprising means for positioning with a precision of less than 0.1 mm.
The present invention is characterised by the special design and configuration of each and every element of a glass printing machine that combines the advantages of a rotary drive with those of a drive based on linear technology. A system of glass transport carriages for digital printing is created, where the carriages move linearly in an “endless” or continuous system, so that the advantages of both systems are obtained:
Therefore, the present invention belongs to the scope of glass printing systems.
Machines with linear drives with limited loads and precisions are known in the state of the art, but none of the linear drives are used for glass printing.
On one hand, linear drives have a load limit of less than 20 Kg: on the other hand, the precision they achieve can be improved.
Moreover, in glass printing, due to the size of the product to be moved, i.e. the glass panes, the machine must turn the printing table 180°, which complicates the operation of the machine and also limits the dimensions of the machine itself and of the products to be moved.
Therefore, the aim of the present invention is to develop a printing machine or system that allows higher loads than those used hitherto, where the precision is higher than 0.08 mm and where the rotation of the printing table is solved, developing a machine such as the one described below, the essence of which is described in the first claim.
The object of the present invention is a glass-printing machine with continuous transportation of the glass, i.e., there are no interruptions in the glass transport process.
The printing machine comprises a loading station where the glass panes to be printed are received, followed by mechanical means for attaching the glass pane, and then a viewing or mechanical positioning system followed by a printing system, and finally an unloading station, with the carriages running between an upper level along the above elements and returning to the starting point via a lower level, the change of level at the loading and unloading station being carried out by means of lifting and lowering drives.
Preferably but not limited to, at the time of printing the carriages are transported with a drive that has an optical linear encoder with a resolution of less than 4 microns.
The continuous movement of the carriages can be carried out in different ways depending on the number of carriages running in the printing machine.
In the case that the machine has two carriages, each one has its own linear drive and a lifting and lowering drive integrated, so that the shifting from the loading station to the unloading station takes place on the upper level thanks to the linear motor integrated in the carriage itself and, upon arrival at the unloading station, the carriage is lowered by means of another drive, returning to the loading station on a lower level but using the same linear drive to finally lift the carriage by means of the lifting and lowering drive.
If the machine has more than two carriages, the carriages are moved by drives independent of the carriages, the carriages returning to the starting point of the machine, once lowered, driven by a system of belts, racks, spindles, pneumatic, but totally independent of the linear movement of the upper level.
The number of carriages and linear motors to drive them will depend on the maximum length of glass to be processed and on the required cycle times.
Each carriage at the inlet of the machine is able to pick up a glass pane with the vertical movement, if available at the loading station.
Each carriage at the outlet of the machine is capable of leaving a glass pane with the vertical movement, if available at the unloading station.
Each carriage has a mechanical fixing system that is activated after receiving the glass. The fixing system consists of stops made of plastic material that can be actuated by a pneumatic cylinder along a guide so that said stops always push on the same position and, therefore, the scanner only has to measure the glass a first time until the glass format is changed again.
By interposing the glass fixing system between the reception of the glass and the viewing means, it is possible to improve the tolerance from a tolerance in a printing system without glass fixing means of +/−0.1 mm to a tolerance of +/−0.08 mm.
The position correction to achieve a tolerance of +/−0.08 can be done in two ways:
The fact that the printing machine has a glass fixing system allows:
Each carriage can be slotted to be integrated and coupled with a loading or unloading belt system for smooth transfer of the glass, or instead the carriage itself can have an integrated roller, belt, or band conveyor.
On the upper level, after the loading station, a vision system can be provided to know the position of each glass, thereby avoiding the installation of the mechanical system.
The installation of a mechanical positioning system or a vision system will depend on the type of glass of the customer and the positioning accuracy, the mechanical system being the most accurate.
The printing machine can be equipped with a cleaning station to clean the carriages after the painted glass has been deposited. In case ink has been spilled on the plane, so that the next glass is not stained.
Alternatively but not exclusively, supports can be placed on each plane, raised above the plane and with quick coupling to configure the machine according to the type of glass. In this way the glass does not touch the table, and the supports are always under the glass to avoid ink stains.
The logical thing to do would be to install either a carriage cleaning station or supports that raise the glass and prevent it from touching the table.
The use of cleaning rollers allows for greater automation of the process, but requires more maintenance and would make the machine more expensive.
The use of raised supports requires an adjustment when changing the type of glass.
The features described above allow a glass printing system with continuous transport to be obtained, with a precision of less than 0.1 mm and allows the handling of large loads, which to all intents and purposes is a major advance in the efficiency and versatility of the machine compared to machines of the state of the art.
Unless indicated otherwise, all the technical and scientific elements used in this specification have the meaning usually understood by a person skilled in the art to which this invention belongs. In the practice of this invention, methods and materials similar or equivalent to those described in the specification may be used.
In the description and claims, the word “comprises” and its variants do not intend to exclude other technical characteristics, additives, components or steps. For persons skilled in the art, other objects, advantages and characteristics of the invention will be partly inferred from the description and partly from the practice of the invention.
In order to complement the description being made herein, and with the object of aiding the better understanding of the characteristics of the invention, in accordance with a preferred practical embodiment thereof, said description is accompanied, as an integral part thereof, by a set of drawings where, in an illustrative and non-limiting manner, the following has been represented:
In view of the figures, a preferred embodiment of the proposed invention is described below.
Wherein the machine comprises an upper level (9) arranged on a lower level (10), a series of carriages (11) running continuously in one direction on the upper level (9) and in the opposite direction on the lower level (10), having means to achieve the lifting and lowering of the carriages between the upper level (9) and the lower level (10).
In a first embodiment, when the machine has more than two carriages to achieve this change of direction, the machine comprises a first vertical drive (7) at the loading station (1) that lifts the carriages (11) from the lower level (10) to the upper level (9) and a second vertical drive (8) at the unloading station (4) that lowers the carriages (11) from the upper level (9) to the lower level (10).
The first and second vertical drives (7) and (8) can be pneumatic, electric, or hydraulic, or driven by linear motors.
On the first level the carriages (11) are driven by linear motors (6), where the number of carriages and linear motors will depend on the maximum length of the glass panes to be processed and the time required.
In this first embodiment the shifting of the carriages is carried out by the linear motors (6) which are independent of the carriages themselves.
In this embodiment, each carriage (11) has a linear drive (18) and a lifting and lowering drive integrated, so that the linear drive (18) allows moving from the loading station to the unloading station at the upper level and back from the unloading station to the loading station at the lower level, while the lifting and lowering drive (19) lowers the carriage (11) from the upper level to the lower level when the carriage is at the unloading station and lifts it from the lower level to the upper level when the carriage is at the loading station.
Having sufficiently described the nature of the present invention, in addition to the manner in which to put it into practice, it is hereby stated that, in its essence, it may be put into practice in other embodiments that differ in detail from that indicated by way of example, and to which the protection equally applies, provided that its main principle is not altered, changed or modified.
| Number | Date | Country | Kind |
|---|---|---|---|
| P202030963 | Sep 2020 | ES | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/ES2021/070680 | 9/20/2021 | WO |
