Sleeve exchange system

Abstract

A system for replacement of sleeves that can be slipped on arbors of Wei y transfer rollers of a printing machine has a storage device, in which the sleeves, which are not used in cl current ink transfer, can be stored, and transport devices, with which several sleeves can be transported to the printing machine, Devices for the transfer of the sleeves with which the sleeves can be transported between the storage device, the transport devices, an, the arbors of the ink transfer rollers include devices for receiving the sleeves, which are associated with a robotic arm such that the devices for receiving the sleeves have three degrees of freedom for translation and are rotatable about at least two axes of rotation.

Claims

1. A system that exchanges sleeves on arbors of ink transfer rollers of a printing machine, said system comprising: a storage device, in which the sleeves which are not used in a current ink transfer are stored; transport devices, with which a plurality of the sleeves are individually transported to the printing machine; devices that transfer the sleeves, with which the sleeves are at least one of transferred to the arbors and transferred from the arbors, the devices that transfer of the sleeves including an arbor-shaped support element that receives thereon the sleeve to a length that is less than a full length of the sleeve, the support element having an external diameter that is variable so as to provide for secured frictional engagement with a corresponding internal diameter of the sleeve during positioning to an initial position of the sleeve on the arbor, and for subsequent disengagement therefrom once the sleeve is positioned at the initial position on the arbor, a slider that is displaceable relative to the device for transfer of the sleeves, so that the sleeves are displaced along a sleeve axis, and a robotic arm having three degrees of freedom for translation, the robotic arm being rotatable about at least two axes of rotation, and having a first joint that provides for coaxial alignment of the sleeve axis with an axis of the arbor, and a second joint that provides for circumferential alignment of the sleeve with the arbor before or during the receipt of the sleeve by the arbor; and sensors, with which a relative angular position of the sleeve to the support element, with respect to a line of alignment with an axis of the ink transfer roller, is determined and communicated, so as to provide for the coaxial alignment of the sleeve axis with the axis of the arbor.

2. The system according to claim 1, wherein the support element projects at least in part into an interior of the sleeves.

3. The system according to claim 1, further comprising a computing and control unit which controls driving devices fOr driving the devices for the transfer of the sleeves in such a manner that the support element can be placed in positions in which a transfer of the sleeves therefrom onto the arbor of the ink transfer rollers, into the storage device, or the inverse, can be carried out.

4. The system according to claim 3, wherein positions of the arbors of the ink transfer rollers, in which a replacement of a sleeves is to be done, and respective target positions and current positions of the sleeves in the printing machine, in the transport devices, and in the storage device are known to the computing and control unit.

5. The system according to claim 3, wherein based on the relative angular positions of the sleeve on the support element with respect to the line of alignment with the axis of the arbor of the ink transfer roller, as determined by the sensors, as well as the target values, the computing and control unit transmits signals to the devices for transfer of the sleeves, until the support element is so positioned that the axis of the arbor of the ink transfer roller is aligned with the axis of the sleeve, if the latter was received by the device for receiving the sleeves.

6. The system according to claim 3, wherein the devices for the transport include a traversable carriage, which assumes a defined position relative to the printing machine for the replacement of the sleeves with the position of the traversable carriage being known to the computing and control unit.

7. A method for replacement of printing sleeves with a system according to claim 3, wherein the computing and control unit determines an arrangement of the sleeves, which are to be replaced, in the transport devices, with one position for receiving at least one more sleeve remaining free in the transport devices.

8. The method according to claim 7, wherein the device for the transfer removes a sleeve from an arbor of an ink transfer roller, and delivers the sleeve to the free position, and the device for the transfer takes a different sleeve from the transport devices, and delivers the different sleeve to the arbor from which the sleeve had been removed.

9. The method according to claim 8, wherein the free position in the transport devices, to which a sleeve, removed from an arbor of the ink transfer roller, is delivered, and the position, from which a next sleeve is taken, are directly adjacent.

10. The system according to claim 1, wherein the robotic arm is configured to at least rotate and tilt the sleeves.

11. The system according to claim 1, wherein the printing machine includes pushing devices, with which the sleeves can be pushed along their axis.

12. The system according to claim 1, wherein the support elements can be coupled and uncoupled with the devices for transfer of the sleeves.

13. A system that exchanges a sleeve with an arbor of an ink transfer roller of a printing machine, said system comprising: a storage device, in which the sleeve, if not used in a current ink transfer, is stored; a transport device, with which the sleeve is transported from the storage device to the printing machine; a device that exchanges the sleeve with the arbor, the device that exchanges the sleeve including an arbor-shaped support element that receives thereon the sleeve to a length that is less than a full length of the sleeve, the support element having an external diameter that is variable so as to provide for secured frictional engagement with a corresponding internal diameter of the sleeve during positioning to an initial position of the sleeve on the arbor, and for subsequent disengagement therefrom once the sleeve is positioned at the initial position on the arbor, and a robotic arm having three degrees of freedom for translation, the robotic arm being rotatable about at least two axes of rotation, and having a first joint that provides for coaxial alignment of an axis of the sleeve with an axis of the arbor, and a second joint that provides for circumferential alignment of the sleeve with the arbor before or during the receipt of the sleeve by the arbor; and a sensor, with which a relative angular position of the sleeve to the support element, with respect to a line of alignment with an axis of the ink transfer roller, is determined and communicated so as to provide for the coaxial alignment of the sleeve axis with the axis of the arbor.

14. The system according to claim 13, wherein the coaxial alignment of the axis of the sleeve with the axis of the arbor is with respect to a substantially vertical direction.

15. A system that exchanges sleeves on arbors of ink transfer rollers of a printing machine, said system comprising: a storage device, in which the sleeves not being used in an ink transfer are stored; transport devices, with which a plurality of the sleeves are individually transported to the printing machine; devices that transfer the sleeves, with which the sleeves are at least one of transferred to the arbors and transferred from the arbors, the devices that transfer the sleeves including an arbor-shaped support element that receives thereon the sleeve to a length that is less than a full length of the sleeve, the support element having an external diameter that is variable so as to provide for secured frictional engagement with a corresponding internal diameter of the sleeve during positioning to an initial position of the sleeve on the arbor, and for subsequent disengagement therefrom once the sleeve is positioned at the initial position on the arbor, and a slider that is displaceable relative to the device for transfer of the sleeves, so that the sleeves are displaced along a sleeve axis; a sensor, with which a relative angular position of the sleeve to the support element, with respect to a line of alignment with an axis of the ink transfer roller, is continuously determined and communicated, so as to provide for the coaxial alignment of the sleeve axis with the axis of the arbor; and a computing and control unit that controls driving devices to drive the devices for the transfer of the sleeves such that the support element is placed in positions in which the transfer of the sleeves therefrom onto the arbor of the ink transfer rollers, into the storage device, or the inverse, is effected, with positions of the arbors of the ink transfer rollers, in which a replacement of a sleeve is to be effected, and respective target positions and current positions of the sleeves in the printing machine, in the transport device, and in the storage device being processed by the computing and control unit so as to effect the transfer.

16. The system according to claim 15, wherein the relative angular position determined by the sensor is communicated to the computing and control unit, which transmits a signal to actuators of the transport devices of the sleeves until the devices for receiving the sleeves are positioned such that the axis of the arbor of the ink transfer roller is aligned with the axis of the sleeve.

17. The system according to claim 15, further comprising a robotic arm having three degrees of freedom for translation, the robotic arm being rotatable about at least two axes of rotation, and having a first joint that provides for coaxial alignment of the sleeve axis with an axis of the arbor, and a second joint that provides for circumferential alignment of the sleeve with the arbor before or during the receipt of the sleeve by the arbor.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The individual figures show:

(2) FIG. 1 A system for replacement of sleeves

(3) FIG. 2 View II-II according to FIG. 1

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(4) Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

(5) FIG. 1 shows a printing machine 1, which comprises the side frames 2 and 3. The ink transfer rollers 4 are supported, turned inwards, on pillow blocks not shown here. The pillow blocks are on guide rails, also not shown, which are mounted on side frame 2 displaceably relative to the side frames. Thus the ink transfer rollers 4 can be adjusted against the counterpressure cylinder, also not shown here, or against each other, so as to ensure the transfer of the ink on the substrate for printing, which is guided by means of the counterpressure cylinder. In the side frame 3, pillow blocks are also mounted displaceably on rails. These pillow blocks are provided with supports, which are movable relative to the pillow blocks, so that the arbor 5 of the ink transfer roller 4 can be optionally supported or released. The sleeves 6, which can be slipped on in the direction z of the arbor 5, can impinge on the ink transfer rollers 4.

(6) To replace the sleeves 6, the pillow blocks in the side frame 3 are first removed from the corresponding ink transfer rollers 4. Then the sleeve can be taken off from the arbor 5 opposite to the direction z and thereafter a new sleeve 6 can be slipped on the arbor. The printing unit 7 illustrates the situation in which the sleeve 6a is taken off from the arbor 5a.

(7) For the delivery or the transport of the sleeves 6, a transport device 8 is provided, which can be moved relative to the printing machine 1. This transport device 8 can be embodied as a palette. In the example shown, the transport device 8 contains a new sleeve 6, which is to be delivered to the arbor 5a of the printing unit 7 that just became free. However, in order to accommodate the sleeve 6a just taken out in the direction of transport 8, it has a free position, which is embodied as a vertically projecting retainer arbor 9.

(8) For the transfer of the sleeves 6 and 6a between tree printing machine 1 and the transport device 8, a transfer device 10 is provided. To convey the sleeves 6, 6a, a support element 11 is provided, which is embodied with an arbor-like shape and projects, for instance, into one third of the interior of the sleeve 6a.

(9) The transfer device 10 is, as one can see in FIGS. 1 and 2, suspended on the rails 13, 14. This suspension enables displacement of the transfer device 10 along a horizontal plane spanned by the direction arrows x and z. For that, driving motors, not shown here, are provided. The transport device exhibits, in addition, two swivel joints 15 and 16, whose axes of rotation extend parallel to the direction arrow x. The swivel joints 15, 16 enable adjustment of the heights of the sleeves 6, 6a in direction y. However, the sleeves 6, 6a can also be tilted so that these 6, 6a can be brought from a vertical position into a horizontal position. The swivel joints are driven by driving motors such as, for example, electromotors.

(10) Due to the aforementioned possibilities of the movement of the transfer device 10, it is now possible to bring a sleeve 6, 6a before an arbor 5, 5a in such a manner that the principal axis of inertia of the sleeve 6, 6a is aligned with the axis of that arbor 5, 5a. Due to the play of the swivel joints 15, 16, as well as also due to the small pitching movement of the arbor 5 during the release of the ends in the area of the side frame 3, it can happen in practice that the named axes are not aligned, but extend away from each other in direction z. In order to counteract against this effect, the transfer device 10 comprises a swivel joint for justification 18, whose axis of rotation also extends in the direction x. By means of sensors not shown, it can be determined whether the axes are aligned or not. If the justification of the axes is complete and the axes extend coaxially, the transfer device 10 as a whole can be displaced in direction z, until the support element 11 touches the arbor 5, 5a. When that is the case, major part of the sleeve 6, 6a is already slipped on the arbor 5, 5a. In order to slip on the sleeves 6, 6a completely on the arbor, the slider 12 is displaceable relative to the transfer device 10 in the direction z. The slider 12 acts thereby on the front side of the sleeve 6, 6a facing the lower support arm 17.

(11) Frequently the arbors 5, 5a of ink transfer rollers have 4 small pins. The sleeves 6, 6a then have complementary grooves, so that when the sleeves are fully slipped on the arbor, the groove surrounds the pin. After the slipping on of the sleeve 6, 6a, it is thus automatically adjusted with respect to its longitudinal axis, as well also in the circumferential direction relative to the arbor. In order that the groove can surround the pin, the transfer device comprises another swivel joint 19, whose axis of rotation extends concentrically to the axis of the sleeve, so that a rotation of the sleeve 6, 6a relative to the arbor 5, 5a before or during the process of slipping on is possible, so that the pin and the groove can be brought in mutual engagement.

(12) If a sleeve 6, 6a is taken off from an arbor 5, 5a, the axes of the corresponding arbor 5, 5a and the support element 11 are adjusted in alignment, so that the axis of the sleeve is also aligned with the axis of the arbor, if the sleeve is slipped on the support element 11, even when it suntil stands in partial contact with the arbor. After the alignment of the orientations, a pushing device 20 pushes the sleeve away from the arbor 5, 5a. Such a pushing device 20 can be provided on each arbor, however, it is shown only for the printing unit 7 for the sake of simplicity. After the process of pushing, the sleeve 6, 6a surrounds the support element 11 completely. It is of advantage if the external diameter of the support element 11 is variable, so that frictional engagement between the support element 11 and the sleeve 6, 6a can be established. After that, the sleeve 6, 6a can be taken off completely from the arbor 5, 5a by the transfer device.

(13) In printing machine 1, the sleeves 6, 6a with different internal diameters can be used. It is especially then the case, if an adapter sleeve is slipped on the arbor 5, 5a at first and thereafter a sleeve 6, 6a is slipped on the adapter sleeve. In order that all the sleeves 6, 6a can remain in frictional engagement with the support element from within, the support elements 11, 11a, 11b are provided with different external diameters. For each of the internal diameter of the sleeve 6, 6a that can be used in printing machine 1, a support element can be provided. Due to the degrees of freedom of the transfer device 10, it can automatically replace the support elements 11, 11a, 11b. For that, the transfer device 10 is provided with a coupling 21, which establishes or interrupts compressed air and/or current connection between the transfer device 10 and the support element.

(14) FIG. 2 shows the view II-II according to FIG. 1. The side frame 3 has the recesses 22 in the area of the individual inking units, through which the ink transfer rollers 4 can be reached in such a manner that the sleeves 6, 6a can be taken off from the arbors 5, 5a through the recesses 22. For the sake of simplicity, of each inking unit, only one ink transfer roller 4 is shown. In general, for instance in flexographic printing machines, there are two ink transfer rollers 4 per inking unit, namely an anilox roller and a printing roller. In particular, both the swivel joints 15, 16 of the transfer device 10 are shown. The rails 14 serve the purpose of moving the transfer device 10 parallel to the frontage of the side frame 3. In order that maximum possible room for movement is available for the transfer device 10, the side frame 3 is devoid of front structures or elevations.

(15) The invention being thus described, it will be apparent that the same may be varied in many ways, Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be recognized by one skilled in the art are intended to be included within the scope of the following claims.

(16) TABLE-US-00001 List of Reference Symbols 1 Printing machine 2 Side frame 3 Side frame 4 Ink transfer roller 5, 5a Arbor 6, 6a Sleeves 7 Printing unit 8 Transport device 9 Retainer arbor 10 Transfer device 11, 11a, b Support element 12 Slider 13 Rails 14 Rails 15 Swivel joint 16 Swivel joint 17 Lower support arm 18 Swivel joint for justification 19 Swivel joint 20 Pushing device 21 Coupling 22 Recess 23 24