Device for removing a textile from a printing plate

Abstract

The present invention relates to a device for releasing a textile from a printing plate, in particular in direct printing and / or screen printing and / or with several colors, comprising a lifting device which has a gripper for gripping a first end of the textile and a first axis of movement for lifting the gripper; and a release slide which can be inserted via a second axis of movement between the printing plate and the first end of the textile lifted by the lifting device in order to release the textile from the printing plate.

Description

The present invention relates to a device for detaching a textile from a printing plate, in particular in direct printing and / or screen printing and / or with multiple colors.In the textile printing industry, in particular in the field of direct printing / screen printing, multicolor complex printing patterns are frequently used. The textile must not slip between the individual printing stations on the printing plate, since otherwise the printed image is distorted or blurred in the print.To counteract this, a double-sided adhesive film is applied between the printing plate and the textile. This prevents the textile from slipping during printing, but has a disadvantageous effect on the removal of the textile and the transfer to the drying tunnel belt. Automatic stripping has not been possible in multicolor printing. Manual pulling is usually inconvenient and expensive for the operator due to the position of the printing plate. In addition, it involves the risk of damage to the still fresh printed image due to an uneven load on the textile during detachment.It is therefore an object of the present invention to provide an apparatus for releasing a textile from a printing plate which replaces the manual release practiced heretofore.This object is achieved by a device according to claim 1. Preferred embodiments of the present invention are the subject matter of the dependent claims.The present invention comprises an apparatus for releasing a textile from a printing plate, comprising a lifting device which has a gripper for gripping a first end of the textile and a first movement axis for lifting the gripper, and a detachment slide which can be pushed via a second movement axis between the printing plate and the first end of the textile lifted by the lifting device in order to detach the textile from the printing plate.The gripper engages and fixes the textile at the first, preferably lower end and "swabs" or lifts it to such an extent that the detachment slide can retract between textile and printing plate. In this case, it releases the textile uniformly from the adhesive film, so that in the next step the textile can be removed manually or automatically.The device according to the invention can be positioned at a suitable position with respect to the printing plate and thus on the one hand eliminates the poor accessibility provided in previous manual detachment. Furthermore, the textile is uniformly detached by the detachment slide, so that damage to the printed image is avoided.The device according to the invention can be combined with a device for automatically removing the textile from the printing plate and therefore allows such automatic removal even in multicolor prints by performing a detachment of the textile from the adhesive film / printing plate before removal. After the release of the textile, the automatic removal and transfer to a drying tunnel can then take place. The device according to the invention, however, also facilitates the removal of the textile by hand.The device according to the invention can be used in particular in direct printing and / or screen printing and / or in printing with a plurality of colors.Furthermore, the device according to the invention can be used in particular if the textile adheres to the printing plate during printing, and is fixed to the printing plate in particular via at least one adhesive layer and in particular a two-sided adhesive film.Furthermore, the device according to the invention can be used in particular for printing a textile which is drawn onto the printing plate with a lower opening and therefore surrounds the latter. The release slide is preferably inserted into this lower opening, the first end corresponding to the lower end of the textile.The device according to the invention can be used in particular for printing T shirts.According to a possible embodiment of the present invention, the gripper is a mechanical gripper with two clamping elements, between which the first end of the textile can be clamped. In particular, the clamping elements can be clamping strips.According to a possible embodiment of the present invention, the detachment slide comprises a push plate which can be moved linearly via a telescopic rail structure.According to a possible embodiment of the present invention, a front edge of the release slide, in particular of the push plate, has a bevel in order to lift and release the textile.According to a possible embodiment of the present invention, the device comprises a size adjustment by which the position of the lifting device is adjustable to the position of a first end of the textile. In this way, different textiles which end at different positions on the printing plate can be printed.According to a possible embodiment of the present invention, the position of the lifting device is adjustable via the size adjustment in a direction parallel to the extension direction of the second movement axis of the detachment slide.According to a possible embodiment of the present invention, the size adjustment comprises a third movement axis, by means of which the position of the lifting device can be adjusted in a direction transverse to the direction of the first movement axis. The third movement axis can be adjustable manually and / or by motor.According to a possible embodiment of the present invention, the position of the lifting device is adjusted with respect to an assembly which comprises the mounting of the detachment slide, wherein the mounting of the detachment slide is preferably not adjusted in its position. The adaptation of the movement of the detachment slide to the size of the textile is usually not necessary or can be effected by adaptation of the travel path of the detachment slide.According to a possible embodiment of the present invention, the position of the lifting device on a support arm which carries a bearing for the detachment slide can be adjusted by the size adjustment.According to a possible embodiment of the present invention, the size adjustment comprises a sensor which detects the position of the first end of the textile and a controller which adjusts the position of the lifting device to the position of the first end of the textile on the basis of the data of the sensor. In particular, the control system actuates an actuator of the size setting for this purpose.The sensor can be, in particular, a vision sensor and / or a camera recognition.According to a possible embodiment of the present invention, the size adjustment allows a manual specification of the position of the lifting device, in particular via a separate input element or an operating panel.According to a possible embodiment of the present invention, the size setting has a projector for projecting a marking, wherein the marking preferably displays the position at which the first end of the textile must be arranged in order to be able to be gripped with the current setting of the size setting. This allows in particular easier manual setting of the position.According to a possible embodiment of the present invention, the gripper comprises a gripping actuator, by means of which it is actuated by motor.According to one possible embodiment of the present invention, the first movement axis comprises an actuator, by means of which it is actuated by motor.According to one possible embodiment of the present invention, the second movement axis comprises an actuator, by means of which it is actuated by motor.According to one possible embodiment of the present invention, the third movement axis comprises an actuator, by means of which it is actuated by motor.The actuators can be, for example, in each case an electric, pneumatic and / or hydraulic actuator.According to one possible embodiment of the present invention, the device comprises a controller which actuates the actuators of the gripper and / or of the first and / or second and / or third movement axis.According to a possible embodiment of the present invention, the control is effected automatically.According to one possible embodiment of the present invention, the actuator or actuators are actuated in such a way that the device carries out the actions and / or method steps described above and below.According to a possible embodiment of the present invention, the controller has an interface for coupling to the controller of a printing press and / or a device for handling printing plates with textiles applied to the latter. In particular, the control of the device according to the invention can be controlled by such an interface.According to one possible embodiment of the present invention, the controller is designed such that the device performs, in particular automatically, the following method:gripping the first side of the textile via the gripper;raising the first side of the textile by moving the gripper by means of the first movement axis;inserting the detachment slide via a second movement axis between the pressure plate and the first end of the textile lifted by the lifting device and releasing the textile from the pressure plate.According to a possible embodiment of the present invention, the control is furthermore effected in such a way that after the pushing in of the detachment slide and detachment of the textile, the detachment slide is moved back via a second movement axis.The device according to the invention can be integrated into a device for handling printing plates or a printing press, in particular as a next-to-last station of such a handling device and / or printing press and / or after the last printing station and / or before the removal station.The present invention further comprises an apparatus for handling printing plates of a printing press, which apparatus comprises an apparatus for releasing a textile from a printing plate as has been described above.According to a possible embodiment of the present invention, the device for handling printing plates comprises a movement axis via which a printing plate can be moved into the region of the device for releasing a textile from the printing plate. Furthermore, the printing plate with the released textile can be moved further over the movement axis to a removal station.According to a possible embodiment of the present invention, the printing plate is movable by the device for handling to at least one printing station and preferably to a plurality of printing stations.In particular, the printing plate with the textile is movable through the device for handling printing plates to one or more printing stations and then to a station formed by the device for detaching the textile.The device for handling printing plates can in particular comprise a rotary table with a plurality of holders of printing plates, and the printing plates transport from one station to the next in a clocked manner.The present invention further comprises a printing press having an apparatus for handling printing plates and / or having an apparatus for releasing a textile as described above.The printing press can furthermore have a drying station on which the textiles are placed after removal from the printing plates.If, within the scope of the present invention, a movement axis is referred to, this means a mechanical guide which allows a movement in at least one direction and / or about at least one axis. However, an axis of movement can also enable more complex movements.In particular, a movement axis according to the present invention may comprise one or more linear axes and or rotational axes.In particular, the above-described axes of movement of the device according to the invention for detaching a textile are each formed by a linear axis.According to one possible embodiment of the present invention, the controller comprises a microprocessor and a nonvolatile memory, on which a program with commands is stored, which, when they run on the microprocessor, control the device and in particular control it such that it performs the activities described within the scope of the present application and / or has functions. Alternatively, the control can also be implemented by hardware or mechanically. The controller is preferably connected to the actuators and, if appropriate, sensors via signal lines.The present invention further comprises methods for operating a printing machine as just described, comprising the steps of:applying a textile to a printing plate, in particular to adhering the textile;printing of the textile, in particular by direct printing and / or screen printing and / or with a plurality of colors;gripping the first side of the textile via the gripper;raising the first side of the textile by moving the gripper by means of the first movement axis;inserting the release slide over a second movement axis between the pressure plate and the first end of the textile lifted by the lifting device and releasing the textile from the pressure plate; and preferably:retracting the detachment slide via a second movement axis.According to a possible embodiment of the present invention, the operation of the device for releasing a textile takes place automatically.The present invention will now be described in more detail with reference to an exemplary embodiment and drawings:The following are shown: FIG. 1 shows an exemplary embodiment of a device according to the invention for detaching a textile in a starting position in which the textile adheres to the printing plate, FIG. 2 shows the exemplary embodiment shown in FIG. 1 in an intermediate position in which the gripper receives the first end of the textile, and FIG. 3 shows the exemplary embodiment shown in FIGS. 1 and 2 in a working stroke in which the detachment slide is inserted between the textile and the pressure plate and releases the textile from the pressure plate.FIGS. 1 to 3 show an exemplary embodiment of a device 10 according to the invention for detaching a textile, which can be integrated into a printing machine, in particular in the area of direct printing / screen printing, for example as a next-to-last station before removal.Reference numeral 20 shows a part of a printing plate handling apparatus of the printing press, by which the printing plates are moved from one station to the next. For example, it can be a rotary table with a plurality of arms on which the pressure plates are arranged.To produce multicolor complex print patterns, the textile 32 must not slip between the individual printing stations on the printing plate 30, since otherwise the printed image is distorted or blurred in the print. To counteract this, a double-sided adhesive film 31 is applied between the printing plate 30 and the textile 32. This prevents the textile from slipping during printing.The device 10 serves to release the textile 32 from the printing plate 30 after printing. It comprises a lifting device with a gripper 11 and a movement axis 14 for lifting the gripper 11, the gripper 11 grips and fixes the textile 32 at the lower end 33. By lifting the gripper 11, it "picking" / lifts the lower end 33 of the textile to such an extent that the detachment slide 12 of the device can retract between the textile 32 and the pressure plate 30. In this case, it releases the textile 32 uniformly from the adhesive film 31, so that in the next step the textile can be removed manually or automatically.The device allows automated release of the textile from the adhesive film / printing plate and consequently subsequently automatic removal even in the case of multicolor prints. However, it can also be combined with manual removal. After removal of the textile, transfer to a drying tunnel belt can take place.In the exemplary embodiment, the gripper 11 comprises a pick-up and clamping / fixing of the textile 32 at the lower end 33 (usually on the side facing the printing press), which is strong enough to withstand the tensile force by the detachment slide 12. In the exemplary embodiment, this is a mechanical gripper with two clamping jaws or clamping strips 19, between which the lower end 33 is clamped. The movement axis 14 lifts the gripper in the exemplary embodiment perpendicularly to the extent of the pressure plate 30 and or the movement direction of the detachment slide. It is preferably driven by a motor.The release slide 12 comprises a push plate on a telescopic rail assembly 15 and is driven by an actuator (electric or pneumatic in nature) inserted between the pressure plate 30 and the textile 32. The pushing plate has a beveled edge 13 at the front to lift and release the textile while it is simultaneously held by the gripper 11. When the detachment slide 12 is pushed back, the textile is again deposited on the printing plate 30 with adhesive film 31, with the difference that this time no adhesion to the adhesive film 31 is built up due to the lack of contact pressure force.Subsequently, the printing plate 30 with the released textile is transported through the device 20 to a removal station, in particular by further turning of the device 20.The operation of the device is preferably automatic. For this purpose, a control, not shown, is provided, which correspondingly actuates the actuators of the device.In the exemplary embodiment, the device 10 for releasing the textile comprises a (preferably automatic) size adjustment 16, by means of which the gripper 10 of the lifting device is aligned with the lower edge 33 of the textile 32 to be printed.For example, in a T shirt, the elevator is moved depending on the size of the shirt. For this purpose, the lifting device in the exemplary embodiment is linearly movable along a support arm 17, in particular via an actuator 18.The position value for the adjustment axis can be preset either by a vision sensor / camera recognition or by a value manually adjustable by the operator (for example with laser line and encoder value or by means of employee input on the operator panel). Depending on the size / length of the textile, the size setting of the lifting and clamping mechanism is therefore adjusted.Furthermore, the travel path of the detachment slide can be adapted to the size of the textile.

Claims

Device for releasing a textile (32) from a printing plate (30), in particular during direct printing and / or screen printing and / or with a plurality of colors, comprising: a lifting device which has a gripper (11) for gripping a first end (33) of the textile (32) and a first movement axis (14) for lifting the gripper (11); and a release slide (12) which can be pushed via a second movement axis between the printing plate (30) and the first end (33) of the textile (32) lifted by the lifting device in order to release the textile (32) from the printing plate (30).Device according to claim 1, wherein the gripper (11) is a mechanical gripper with two clamping elements (19), between which the first end (33) of the textile (32) can be clamped.The device according to claim 1 or 2, wherein the detachment slide (12) comprises a push plate which is linearly movable via a telescopic rail structure (15).The apparatus of any preceding claim, wherein a front edge (13) of the release slide (12) has a chamfer to lift and release the textile.The device according to any one of the preceding claims, comprising a size adjustment (16) by which the position of the lifting device is adjustable to the position of the first end (33) of the textile (32), wherein the position of the lifting device is preferably adjustable in a direction parallel to the extension direction of the second movement axis of the detachment slide (12).Device according to claim 5, wherein the position of the lifting device on a support arm (17) which carries a bearing for the detachment slide (12) is adjustable by the size adjustment (16).The device according to claim 5 or 6, wherein the size adjustment (16) comprises a sensor which detects the position of the first end (33) of the textile (32), and a controller which adjusts the position of the lifting device to the position of the first end (33) of the textile (32) based on the data of the sensor, wherein the sensor is preferably a vision sensor and / or a camera recognition.The device according to any one of claims 5 to 7, wherein the size setting (16) allows a manual specification of the position of the lifting device, in particular via a separate input element or an operating panel and / or wherein the size setting (16) has a projector for projecting a marking, wherein the marking preferably displays the position at which the first end (33) of the textile (32) must be arranged in order to be able to be gripped with the current setting of the size setting.Device according to one of the preceding claims, wherein the gripper (11) comprises a gripping actuator via which it is actuated, and / or wherein the first and / or the second movement axis comprise an actuator via which they are actuated.Device according to one of the preceding claims, having a controller which actuates, in particular automatically actuates, actuators of the gripper (11) and / or of the first and / or second movement axis, wherein the controller preferably comprises an interface for coupling to the controller of a printing press and / or a device for handling printing plates having textiles applied to the latter.The device according to claim 10, wherein the controller is configured to perform the following method: - gripping the first side (33) of the textile (32) via the gripper (11); - lifting the first side (33) of the textile (32) by moving the gripper (11) by means of the first movement axis; - inserting the detachment slide (12) via a second movement axis between the pressure plate (30) and the first end (33) of the textile (32) lifted by the lifting device and detaching the textile (32) from the pressure plate (30); and preferably: - retracting the detachment slide (12) via a second movement axis.Device (20) for handling printing plates of a printing press having a device (10) for releasing a textile (32) from a printing plate (30) according to one of the preceding claims, wherein the device (20) for handling printing plates (30) preferably comprises a movement axis via which a printing plate (30) can be moved into the region of the device (10) for releasing a textile (32) from the printing plate (30), wherein the printing plate (30) can be moved by the device (20) for handling preferably to at least one printing station and preferably to a plurality of printing stations.Printing machine having a device (20) for handling printing plates according to Claim 12 and / or having a device for releasing a textile according to one of Claims 1 to 11.Method for operating a printing press according to claim 13, with the steps: - applying a textile (32) to a printing plate (30); - printing the textile (32), in particular by direct printing and / or screen printing and / or with a plurality of colors; - gripping the first side (33) of the textile (32) via the gripper (11); - lifting the first side (33) of the textile (31) by moving the gripper (11) by means of the first movement axis; - pushing the detachment slide (12) via a second movement axis between the printing plate (30) and the first end (33) of the textile (32) lifted by the lifting device and detaching the textile (32) from the printing plate (30); and preferably: - retracting the detachment slide (12) via a second movement axis.The method of claim 14, wherein the operation of the textile release device is automatic.

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