PRINTING MACHINE AND PRINTING SYSTEM HAVING SCREEN MAGAZINE FOR PRINTING ON PLANAR SUBSTRATES

Abstract

The application relates to a printing machine for printing on planar substrates, in particular circuit boards, including: a printing table which extends in a horizontal plane and on which at least one substrate to be printed on can be arranged; at least one printing device assigned to the printing table, which printing device has a screen holder for an interchangeable printing screen and a doctor device assigned to the screen holder, wherein, by means of the doctor device, a printing material can be applied onto the substrate to be printed on through the printing screen; and a screen magazine assigned to the doctor device for storing at least one printing screen for the doctor device. According to the invention, the screen magazine has a housing with at least two drawers which are arranged in parallel to one another and are each designed to hold one printing screen, wherein the housing is pivotably arranged such that it can pivot between a first end position, in which the drawers are oriented parallel to the horizontal plane, and a second end position, in which the drawers are oriented at an angle to the horizontal plane, in particular vertical thereto.

Claims

1. A printing machine for printing on planar substrates, comprising: a printing table which extends in a horizontal plane and on which at least one substrate to be printed on can be arranged; at least one printing device assigned to the printing table, which printing device has a screen holder for an interchangeable printing screen and a doctor device assigned to the screen holder, wherein, by means of the doctor device, a printing material can be applied onto the substrate to be printed on through the printing screen; and a screen magazine assigned to the doctor device for storing at least one printing screen for the doctor wherein the screen magazine has a housing with at least two drawers which are arranged in parallel to one another and are each designed to hold one printing screen, wherein the housing is pivotably arranged such that it can pivot between a first end position, in which the drawers are oriented parallel to the horizontal plane, and a second end position, in which the drawers are oriented at an angle to the horizontal plane.

2. The printing machine according to claim 1, wherein the housing is oriented at least substantially vertically to the drawers in the second end position.

3. The printing machine according to claim 1, wherein the housing is mounted to be height-adjustable at least in the first end position.

4. The printing machine according to claim 1, comprising a device designed to insert a printing screen into one of the drawers and pull it out of the drawers.

5. The printing machine according to claim 1, wherein the device has a magnetically operated gripping device.

6. The printing machine according to claim 1, wherein the device is designed separately from the doctor device.

7. The printing machine according to claim 1, wherein the device is formed by the doctor device.

8. The printing machine according to claim 1, wherein the device is formed by a camera device movable across the printing table.

9. The printing machine according to claim 1, comprising a frame on which the printing table, the doctor device and the screen magazine are arranged.

10. The printing machine according to claim 1, wherein the housing is mounted on the frame such that it is displaceable in height.

11. The printing machine according to claim 1, wherein the housing is mounted on the frame by a linearly displaceable pivot joint.

12. The printing machine according to claim 1, wherein at least one controllable actuator for shifting and/or pivoting the screen magazine is assigned to the housing.

13. The printing machine according to claim 1, wherein the actuator is designed as an electric, hydraulic, or pneumatic actuator.

14. The printing machine according to claim 1, wherein the screen magazine is designed to hold differently sized printing screens.

15. The printing device according to claim 1, wherein the respective drawer is designed to hold the respective printing screens and a doctor tool, comprising a doctor blade, assigned to the respective printing screen.

16. The printing machine according to claim 1, wherein the screen magazine is retained interchangeably on the frame.

17. The printing machine according to claim 1, wherein the screen magazine has a means for pushing out and retracting printing screens out of and/or into one of the drawers.

18. A printing system for printing on planar surfaces, comprising: a printing machine according to claim 1; and at least one printing screen designed to be held in one of the drawers of the screen magazine.

19. The printing system according to claim 18, wherein the printing screen is designed to hold a doctor tool, comprising a doctor blade, and in that the respective drawer is designed to hold the printing screen together with the doctor tool.

Description

[0025] The invention will be explained in more detail below with reference to the drawings. Therein,

[0026] FIG. 1 shows a perspective representation of an advantageous printing machine,

[0027] FIGS. 2A and 2B show the printing machine in different operating states, each in a side view, and

[0028] FIG. 3 shows a detailed perspective view of the printing machine.

[0029] FIG. 1 shows a perspective representation of an advantageous printing machine 1 designed to print on planar substrates with a, in particular electrically conductive, printing material or paste to produce circuit boards, for example. As such, printing machine 1 has a frame 2, carrying a housing 3 which protects the components of printing machine 1 located on the inside of housing 3 from external influences. In housing 3, a printing table 4 is arranged, having a support surface 5 extending horizontally for supporting one or more substrates to be printed on. Preferably, printing table 4 is movable in height, as shown by a double arrow 6, to ensure an optimum height position of a substrate to be printed on. Above printing table 4, i.e., opposite support surface 5, printing machine 1 also has a doctor device 7. Doctor device 7 has a first carriage 8 displaceable across printing table 4 along a rail guide 9 extending horizontally, and a second carriage 10 mounted on first carriage 8 so as to be displaceable transversely to the pushing direction of rail guide 9. A doctor blade mount 11 is arranged on second carriage 10 and designed to hold and actuate a doctor tool, in particular a doctor blade 36.

[0030] A screen holder 12 is arranged vertically between printing table 4 and carriage 9, 8. Advantageously, screen holder 12 has a drawer-type rail guide 13, extending in parallel to rail guide 9 and having, just like rail guide 9, guide rails 13_1, 13_2, e.g., screen or stencil support strips, arranged on either side of printing table 4 in parallel to one another. Rail guide 13 is designed to guide or carry a printing screen on the edges, so that a printing material is able to be applied to the printing screen and is printable on a substrate supported on printing table 4 through the printing screen by means of a doctor blade arranged on doctor blade mount 11.

[0031] Furthermore, printing machine 1 has a camera device 14, having a camera 15 which is arranged to be movable vertically between doctor device 7 and printing table 4. For this purpose, camera 15, just like doctor blade mount 11, is retained on a carriage 16 mounted on a carriage 17 to be displaceable longitudinally, wherein carriage 17 is displaceable longitudinally in parallel to rail guide 9 of doctor device 7 above printing table 4 and displaceable below doctor device 7. This allows to move camera 15 across the entire printing table 4. Preferably, in this case, camera 15 is arranged or designed such that it is assigned to printing table 4 and/or doctor device 7, in particular screen holder 12, to check the position of a substrate supported on printing table 4 and/or the position of a printing screen held in rail guide 13 or screen holder 12 before a printing process is carried out. For example, if a deviation of a current actual position of a printing substrate or printing screen from a target position is detected, then either an automated adjustment is performed or the operator of printing machine 1 is advised to align the substrate and/or the screen correctly.

[0032] Furthermore, printing machine 1 has an advantageous screen magazine 18 operable to simplify, in particular automate, conversion of printing machine 1 for the printing process with another printing screen than the one used before.

[0033] According to the present exemplary embodiment, screen magazine 18 has two drawers 20, 21 arranged in parallel to one another in a housing 19. Each drawer 20, 21 is operable to hold at least one printing screen, wherein a printing screen 22 is arranged in drawer 20 and a printing screen 23 is arranged in drawer 21 according to the present exemplary embodiment. Preferably, the printing screens have different printing structures.

[0034] FIG. 2A shows a side view of printing machine 1 in the state also shown in FIG. 1. Here, screen magazine 18 is oriented vertically, so that printing screens 22, 23 located therein are arranged standing vertically next to each other, as indicated by dashed lines in FIG. 2A, and thus at an angle of almost or exactly 90° to the plane along which support surface 5 of printing table 4 or screen holder 12 extends, as also indicated by a dashed line in FIG. 2A.

[0035] Due to housing 19 being designed with only two drawers 20, 21 to hold two printing screens 22, 23, housing 19 only slightly protrudes laterally from housing 3 of printing machine 1 in the vertical end position. As such, the space next to printing machine 1 in the region of screen magazine 18 can be used for something else. As an example, the space next to printing machine 1 is a corridor or path 24 adjacent a production line in the production hall.

[0036] Screen magazine 18 is mounted pivotably particularly on frame 2, so that it is pivotable from the vertical end position shown in FIG. 2A into the horizontally oriented end position shown in FIG. 2B, as indicated by an arrow 25. For this purpose, screen magazine 18 is secured on frame 2 by a swivel or pivot joint 26. As such, pivot joint 26 or the axis of rotation formed by pivot joint 26 is conveniently arranged on the upper end of housing 19 or screen magazine 18 in the vertical orientation. In this way, free end 27 of screen magazine 18, located at the bottom in FIG. 2A, is pivotable around the axis of rotation of pivot joint 26, at least until screen magazine 18 reaches the horizontal orientation, as shown in FIG. 2B. In this state, printing screens 22, 23 located in drawers 20, 21 are then located parallel to one another and are oriented horizontally on top of each other, wherein printing screen 23 is located above printing screen 22 according to the present exemplary embodiment. In the horizontal end position, as shown in FIG. 2B, at least one of drawers 20, 21 is located at the height of rail guide 13, so that by simply displacing the printing screen located in this drawer, it is shiftable into the printing position from housing 19 of screen magazine 18 on rail guide 13 of screen holder 12. In FIG. 2B, a respective example of rail guide 13 is shown by a dashed line. In order for second drawer 20 also being able to be assigned to rail guide 13, pivot joint 26 is preferably mounted on frame 2 to be displaceable in height, as shown by a double arrow 28 in FIG. 2B. With this displacement in height, the one or the other drawer 20, 21 can be assigned to rail guide 13 and hence the one or the other printing screen is able to be pushed out of housing 19 or inserted into housing 19. Alternatively or additionally, screen holder 12 or rail guide 13 is shiftable or displaceable in height by means of a controllable actuator according to double arrow 28 to move screen holder 12 and desired drawer 20 or 21 in a common plane.

[0037] According to an advantageous exemplary embodiment of printing machine 1, a gripping device 29 is arranged on carriage 16 of camera device 14, as shown in FIG. 1, by which printing screens 22, 23 are displaceable. As a result, camera device 14 also forms a device 30 which inserts a printing screen into one of drawers 20, 21 and pulls it out of one of drawers 20, 21 and into screen holder 12 as needed. In this case, gripping device 29 is designed as a transport pin, for example, to mechanically engage behind and displace a printing screen, or as a magnetic gripper generating a magnetic field, in particular by electrification, cooperating with respective printing screen 22, 23 to displace the same. For this purpose, printing screens 22, 23 are correspondingly made from a material or have a material in at least parts thereof, which cooperates with the magnetic gripper.

[0038] As an example, a conversion process of printing machine 1 takes place as follows. A printing screen, e.g., printing screen 23, is already located on guide rails 13_1, 13_2 of screen holder 12, and a printing process has already been carried out by means of printing screen 22. Now, another printing process is to be accomplished, requiring another print pattern, so that an exchange of printing screen 22 with printing screen 23 is necessary. First, existing printing screen 22 is inserted into the free drawer, e.g., drawer 21, by camera device 14 or gripping device 30 along rail guide 13. For this purpose, screen magazine 18 is shifted from the vertical end position into the horizontal end position in advance, as shown in FIG. 2B, and adjusted in height as needed, so that drawer 20 is located at the height of rail guide 13. This ensures easy insertion of printing screen 22 into screen magazine 18. Then, screen magazine 18 is adjusted in height, so that the other drawer with printing screen 23 located therein is at the height of rail guide 13. Now, gripping device 30 grips printing screen 23 assigned to rail guide 13, e.g., magnetically, and pulls it out of drawer 21 onto the rail guide and up to the desired position above printing table 4, so that a printing process is able to be performed by means of printing screen 23. In this way, the conversion is particularly performed in a fully automated manner and in a short time. During the printing process or multiple printing processes in which the same printing screen 23 is employed, housing 19 is conveniently adjusted to the vertical end position, as shown in FIG. 2A, so that the passage along path 24 is cleared. Housing 19 of screen magazine 18 protrudes into and may block path 24 only in the horizontally oriented end position. Screen magazine 18 thus serves as a changing device or conversion device for printing machine 1.

[0039] In the vertical end position, as shown in FIG. 2A and also in FIG. 1, screen magazine 18 can be equipped with printing screens by an operator or in an automated manner. As a result, a conversion process of printing machine 1 can be prepared while a printing process is being carried out and without screen magazine 18 taking up a lot of installation space next to printing machine 1, in particular in the region of path 24.

[0040] For shifting and pivoting screen magazine 18, at least one actuator 31 is preferably present, which is designed as an electromotively, pneumatically or hydraulically operated actuator 31, for example, and pivots and/or adjusts screen magazine 18 in height. To achieve the latter, for example, pivot joint 26 is displaceably mounted on a rail guide on frame 2 and displaceable by actuator 31 or another actuator.

[0041] Optionally, screen magazine 18 is releasably or interchangeably retained particularly on frame 2, so that it can be removed from printing machine 1 by an operator or a robot, in particular a material handling tool, and moved to another location, for example for equipment with further or other printing screens as needed. Alternatively, screen magazine 18 is particularly secured on the frame in a permanent or fixed manner.

[0042] FIG. 3 shows a further perspective representation of an enlarged detailed view of printing machine 1 in the region of screen magazine 18, in which housing 19 of screen magazine 18 is removed to show the internal structure of screen magazine 18.

[0043] As an example, drawers 20, 21 are formed by guide rails 32 arranged laterally or by plate-like supports. As such, drawers 20, 21 are designed sufficiently high to hold one printing screen 22, 23 each. In the exemplary embodiment shown in FIG. 1 and FIG. 3, printing screens 22, 23 are arranged in drawers 20, 21. In contrast to FIG. 1, FIG. 3 shows screen magazine 18 in the horizontal end position.

[0044] Each of the respective printing screens 22, 23 has a screen frame 33 on which a screen 34 is retained, in particular clamped. The screen may be a printing stencil or a printing mask. In addition, a retaining device 35 for holding a doctor tool, in particular a doctor blade 36, is arranged on respective frame 33. As such, retaining device 35 is firmly connected to frame 33, so that a doctor blade 36 is able to be carried along with the respective printing screen 22, 23.

[0045] This improves the conversion of printing machine 1 in that not only a printing screen, but also a doctor blade to be used with the printing screen can be exchanged or converted in an automated manner. It is thereby achieved, for example, that printing screens 22, 23 can be loaded with different printing materials and processed with different doctor blades without requiring a doctor blade to be exchanged or in particular cleaned during conversion of printing machine 1.

[0046] According to a further exemplary embodiment, gripping device 30 is not formed by camera device 14 but by doctor device 7. For this purpose, carriage 10 has gripper 15, for example. Alternatively, doctor blade mount 11 is designed to grip doctor blade 36 automatically. As soon as it grips doctor blade 36 of a printing screen 23 arranged in screen magazine 18, it can move printing screen 23 as a whole by moving doctor blade 36. As a result, printing screens 22, 23 in printing machine 1 are converted by doctor device 7 without requiring additional gripping devices or the like. Optionally, screen magazine 18 has a means 37, in particular a pusher, assigned to respective drawer 20, 21, as shown in FIG. 2B as an example, by which at least a part of printing screen 22, 23 respectively located in drawer 20, 21 can be pushed out of housing 18 in the direction of screen holder 12, so that gripping respective printing screen 22, 23 by device 30, in particular by doctor device 7, is simplified. Together with printing screens 22, 23 and in particular with further printing screens not shown herein, having different print patterns, for example, and in particular designed to be held in drawers 20, 21 and in screen holder 12, printing machine 1 forms an advantageous printing system.