JP5310277B2 - Offset printing method and apparatus - Google Patents

Description

  The present invention relates to an offset printing method and apparatus used for performing a fine print pattern on a print target with high printing accuracy as in the case of forming an electrode pattern on a substrate by printing.

  In recent years, as a method of forming an electrode pattern (conductive pattern) such as a liquid crystal display on a required substrate, a printing technique using a conductive paste as a printing ink instead of fine processing such as etching of a metal vapor deposition film, for example, A technique for printing and forming an electrode pattern on a substrate using an intaglio offset printing technique has been proposed (see, for example, Patent Document 1 and Patent Document 2).

  When the electrode pattern of the liquid crystal display or the like is formed on the substrate, an electrode width as fine as about 10 μm may be required, for example. Furthermore, a plurality of electrode patterns may be formed on the substrate in a superimposed manner. In this case, the electrode pattern is overprinted by replacing the plate, but the electrode pattern may be destroyed if the printing position is shifted. Therefore, although the required accuracy differs somewhat depending on the object, it may be necessary to suppress the overlay deviation to several μm in a fine electrode pattern in which the electrode width is about 10 μm.

  For this reason, printing of electrode patterns on the substrate requires extremely high printing accuracy compared to conventional general offset printing that prints characters and images on paper or the like. As an offset printing apparatus for printing, it is advantageous to use a flat plate printing apparatus of a type that uses a flat plate similar to a printing target as a plate.

  FIG. 6 shows a conventionally proposed offset printing apparatus using a flat plate. A guide rail 2 is provided on a base 1 and is driven by a servo motor 4 in parallel with the guide rail 2. A moving table 7 provided with a ball screw mechanism 3 so that a flat plate (master plate) 5 and a printing object (work plate) 6 can be fixed at a fixed interval is slidably attached to the guide rail 2. At the same time, the ball screw mechanism 3 can reciprocate.

  Further, a transfer provided with a blanket roll 9 extending in a direction perpendicular to the guide rail 2 and a roll driving servo motor 10 connected to one end of the blanket roll 9 in the axial direction at a required portion of the base 1. As a configuration in which the apparatus 8 is provided, the blanket roll 9 is rotated at a required speed by operating the servo motor 10 in the transfer apparatus 8, and the peripheral speed of the rotating blanket roll 9 and the plate 5 and the printing object 6 are held. When the plate 5 and the printing object 6 on the moving table 7 are passed directly under the rotating blanket roll 9 while synchronizing the moving speed of the moving table 7, the blanket roll 9 is moved with the plate 5. By sequentially contacting the surface of the printing object 6 with a required contact pressure (printing pressure), transfer (receiving) from the plate 5 to the blanket roll 9 is performed. ) And, to carry out the re-transfer (printing) from the blanket roll 9 to the print object 6 are also available implement offset printing (e.g., see Patent Document 3).

  Note that the peripheral speed of the rotating blanket roll 9 is the value per unit time of the amount of circumferential movement calculated as the product of the rotational angle and the rotational radius of the peripheral position, that is, the angular velocity that is the rotational angle per unit time. Therefore, in order to obtain the peripheral speed of the blanket roll 9, it is necessary to detect the rotation angle of the blanket roll 9.

  Therefore, conventionally, the rotation angle of the blanket roll 9 is detected based on a detection signal of the rotation amount of the servo motor 10 by an encoder (not shown) attached (built in) to the servo motor 10 that drives the blanket roll 9. Therefore, it is widely and generally performed to derive the peripheral speed of the blanket roll 9.

  Further, in a printing apparatus using a blanket roll, when the blanket roll is driven by a motor via a reduction gear (reduction gear), an encoder (rotary encoder) is attached to the driving motor. (For example, refer to Patent Document 4) When the rotation angle of the blanket roll is detected based on a detection signal of the rotation amount of the motor by the encoder, the reduction ratio of the reduction gear provided between the motor and the blanket roll It is considered that the resolution is improved according to the above.

Japanese Patent No. 2797567 Japanese Patent No. 3904433 JP-A-6-15809 JP 2006-243181 A

  However, in order to achieve a very high printing accuracy required when printing a fine print pattern such as the electrode pattern described above by offset printing, a print pattern transferred (accepted) from a plate to a blanket roll, In addition, it is necessary to further improve the reproducibility of both of the print patterns to be retransferred (printed) from the blanket roll to the printing target. For this purpose, the plate and the printing target on the peripheral wall of the rotating blanket roll are in contact with each other. Precise synchronization of the speed (circumferential speed) obtained as the amount of circumferential movement per unit time of the part and the speed (moving speed) obtained as the amount of movement per unit time of the plate or printing object contacting the blanket roll Is required.

  However, the detection of the rotation angle of the blanket roll based on the detection signal of the encoder (not shown) attached to the servo motor 10 for driving the blanket roll 9 shown in Patent Document 3 above, or the blanket roll shown in Patent Document 4 In the detection of the rotation angle of the blanket roll based on the detection signal of the encoder attached to the motor for driving the motor via the speed reducer, there is a concern that the detection accuracy may be insufficient.

  That is, when the rotation angle of the blanket roll is detected based on the detection signal of the encoder built in the servo motor that drives the blanket roll or the detection signal of the encoder attached to the motor connected to the blanket roll via a speed reducer The detection result includes an error due to torsional deformation of mechanical parts in the servo motor and the speed reducer, and an error due to gear backlash in the power transmission mechanism using the gear.

  For this reason, when printing with very high accuracy that is required to suppress the positional deviation of the printing position to several μm, as described above included in the detection result of the rotation angle of the blanket roll. The effects of errors caused by torsional deformation of mechanical parts and gear backlash cannot be ignored.

  However, even if there are errors due to torsional deformation of the machine parts and gear backlash as described above, it is possible to detect the blanket roll rotation angle to the extent required for conventional general offset printing. Since the accuracy was sufficient, in order to further improve the detection accuracy of the rotation angle of the blanket roll driven to rotate by the motor, there is no idea to install a new angle measuring device other than the encoder attached to the motor. The fact is that it has not been proposed in the past.

Also, regarding the rotational radius of the blanket roll circumferential position required for calculating the peripheral speed of the blanket roll, there is an eccentricity in the blanket roll due to manufacturing accuracy, etc., or the cross-sectional shape is true. When distorted from the circular shape, a change occurs in the apparent radius from the rotation center of the blanket roll to the circumferential position according to the rotation angle of the blanket roll, and due to the change in the apparent radius, in some predetermined rotational speed have rotated the blanket roll, the peripheral speed is the circumferential movement amount per since changes in the circumferential movement amount arising unit time in accordance with the rotation angle of the blanket roll The fact is that changes will occur.

  Therefore, conventionally, it is difficult to achieve precise synchronization between the peripheral speed of the blanket roll and the moving speed of the plate or the printing target. For this reason, it is required to suppress the positional deviation of the printing position to several μm. However, there is a problem that it is difficult to perform very high precision printing.

  Therefore, the present invention can measure the rotation angle of the blanket roll with higher accuracy, and the blanket roll has an apparent radius from the rotation center to the circumferential position according to the rotation angle due to eccentricity or the like. Even if there is a change in the speed, the circumferential movement amount of the blanket roll can be accurately detected, the speed (circumferential speed) obtained as the circumferential movement amount per unit time of the blanket roll, and the plate Offset that can achieve precise synchronization of the movement speed of the printing object and the printing object, so that it is possible to perform very high-precision printing that requires that the positional deviation of the printing position be suppressed to several μm. It is an object of the present invention to provide a printing method and apparatus.

  In order to solve the above-mentioned problems, the present invention, corresponding to claim 1, is held on a plate table running on a guide rail on a gantry in a state where a blanket roll is rotated by a drive motor for rotation. The plate is brought into contact with the plate from above, and then the rotated blanket roll is brought into contact with the printing object held on the printing object table running on the guide rail from above, so that the plate is transferred from the plate to the blanket roll. In the offset printing method in which transfer and re-transfer from the blanket roll to the printing object are performed, the correlation between the rotation angle of the blanket roll and the apparent radius from the rotation center of the blanket roll to the circumferential position is obtained. Preliminarily obtained and stored in the database, the plate and printing on the plate table with the blanket roll rotated When contacting each printing object on the elephant table, the apparent radius from the rotation center of the blanket roll from the rotation center of the blanket roll to the portion in contact with the plate or printing object is determined based on the information on the rotation angle of the blanket roll. Calling, the apparent rotational radius and the angular velocity of the rotating blanket roll, the peripheral speed of the blanket roll plate or the part in contact with the printing object, and the plate by running the plate table The offset printing method is configured to synchronize the moving speed and the moving speed of the printing target accompanying the traveling of the printing target table.

  In the above configuration, the rotation angle of the blanket roll is detected by an encoder directly connected to the end face of the rotation shaft opposite to the rotation shaft connected to the rotation drive motor among the rotation shafts at both ends of the blanket roll. Like that.

  Further, according to claim 3, a plate table and a printing target table that run on the guide rail on the gantry, the plate held on the plate table, and the printing target held on the printing target table, The blanket roll that is moved up and down by the lift drive mechanism is sequentially contacted from above in the state of being rotated by the drive motor for rotation, so that the transfer from the plate to the blanket roll and the retransfer from the blanket roll to the printing target are performed. In the offset printing apparatus, a displacement meter for measuring a distance from the outer peripheral surface of the blanket roll is provided at a required position away from the outer periphery of the blanket roll, and an encoder for detecting the rotation angle of the rotating blanket roll Further, based on the signals input from the displacement meter and the encoder, A function of preliminarily obtaining the correlation between the rotation angle of the lanquet roll and the apparent radius from the rotation center of the blanket roll to the circumferential position and storing it as data; and a plate on the plate table in a state where the blanket roll is rotated, and Based on the information about the rotation angle of the blanket roll input from the encoder when contacting each print target on the print target table, the stored data is used to convert the blanket roll from the rotation center to the plate or print target. The apparent radius to the contacted part is called, and the blanket roll plate or print is the product of the called apparent radius and the angular velocity of the blanket roll detected based on the signal input from the encoder. The function to determine the peripheral speed of the part in contact with the object, and the calculated peripheral speed of the blanket roll An offset printing device having a structure comprising a control unit having a function to synchronize the movement speed of the printing by the running of the plate table and the moving speed of the print target by the running of the printing target table, respectively.

  Further, in the above configuration, the encoder for detecting the rotation angle of the blanket roll is directly connected to the end face of the rotation shaft opposite to the rotation shaft connected to the rotation drive motor among the rotation shafts at both ends of the blanket roll. It is set as the structure made to provide.

According to the present invention, the following excellent effects are exhibited.
(1) In a state where the blanket roll is rotated by a driving motor for rotation, the blanket roll is brought into contact with the plate held on the plate table running on the guide rail on the gantry from above, and then the rotated blanket roll is The printing object held on the printing object table running on the guide rail is brought into contact from above so that the transfer from the plate to the blanket roll and the re-transfer from the blanket roll to the printing object are performed. In the offset printing method, the correlation between the rotation angle of the blanket roll and the apparent radius from the rotation center to the circumferential position of the blanket roll is obtained in advance and stored in a database, and the blanket roll is rotated. When contacting the plate on the plate table and the print target on the print target table, respectively Based on the information on the rotation angle of the blanket roll, the apparent radius from the rotation center of the blanket roll to the portion in contact with the plate or the printing object is called from the database, the apparent rotation radius called The blanket roll plate guided by the product of the angular velocity of the rotating blanket roll and the peripheral speed of the portion in contact with the printing object, the movement speed of the plate by the traveling of the plate table, and the traveling of the printing object table Since the offset printing method and apparatus are configured to synchronize the movement speed of the printing object, the blanket roll is used when the rotating blanket roll is brought into contact with the plate on the plate table or the printing object on the printing object table. The peripheral speed of the contact portion of the outer peripheral surface of the plate and the printing target, and the plate or printing target It is possible to perform precise synchronization of the moving speed. Therefore, even if the apparent radius from the rotation center to the circumferential position is uneven due to the eccentricity or the like, the blanket roll prints the printing pattern of the plate on the printing target with high reproducibility. Therefore, it is possible to perform high-precision printing of a very fine print pattern that is required to suppress the positional deviation of the print position to several μm, such as an electrode pattern.
(2) The rotation angle of the blanket roll is detected by an encoder directly connected to the end surface of the rotation shaft opposite to the rotation shaft connected to the rotation drive motor among the rotation shafts at both ends of the blanket roll. Thus, the rotation angle of the blanket roll can be accurately measured in a state that does not include errors due to torsional deformation of machine parts and errors due to gear backlash. Further, since the angular velocity of the rotating blanket roll can be detected with high accuracy based on the signal of the encoder, the peripheral speed of the contact portion with respect to the plate or the printing target on the outer peripheral surface of the blanket roll, the plate or the printing target Since the movement speed of the image can be more precisely synchronized, the printing accuracy can be further improved.

It is a schematic side view which shows one Embodiment of the offset printing method and apparatus of this invention. It is a side view which expands and shows the transfer mechanism part in the offset printing apparatus of FIG. It is an AA direction arrow line view of FIG. It is a schematic diagram which shows the control structure of the controller with which the offset printing apparatus of FIG. 1 is equipped. FIG. 10 is a cut-away side view of a transfer mechanism unit according to another embodiment of the present invention. It is a perspective view which shows the outline | summary of the offset printing apparatus using the flat plate conventionally proposed.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  1 to 4 show an embodiment of an offset printing method and apparatus according to the present invention, which is as follows.

  That is, a guide rail 12 extending in one direction (X-axis direction), for example, a set of two guide rails 12 is provided on the upper side of the horizontal frame 11, and a plate 13 such as an intaglio is provided on the upper surface of the guide rail 12. A plate table 14 that is attached to and held on the top surface and a printing target table 16 that is attached and held on the upper surface portion of the printing target 15 such as a substrate are arranged in order from one end side in the longitudinal direction of the guide rail 12 (left side in FIG. 1). In this state, they are slidably attached via the individual guide blocks 12a.

  Further, the plate table 14 and the printing target table 16 are allowed to move (run) independently along the guide rail 12 by an individual table driving device 17 such as a linear motor. A linear scale 18 is provided on the gantry 1 so as to be parallel to the guide rail 12, and the linear scale 18 is used to position the plate table 14 and the printing target table 16 along the longitudinal direction of the guide rail 12; That is, the absolute position in the X-axis direction with reference to a required point in the X-axis direction can be detected together.

  At a position corresponding to the longitudinal direction intermediate portion of the guide rail 12 on the gantry 11, it is disposed above the guide rail 12 so as to extend in a direction perpendicular to the longitudinal direction of the guide rail 12 (Y-axis direction). A blanket roll 20, a roll support frame 22 that rotatably holds the rotation shafts 21 a and 21 b at both left and right ends of the blanket roll 20, and one rotation shaft 21 a of the blanket roll 20 for rotationally driving the blanket roll 20. A rotation drive motor 23 connected to the blanket roll 20, an encoder 24 directly connected to the other rotary shaft 21b of the blanket roll 20 for detecting the rotation angle of the blanket roll 20, and the blanket roll 20 integrally with the roll support frame 22. Transfer mechanism section provided with a lift drive mechanism 25 for driving the lift 9 is provided.

  Further, the blanket roll 20 is temporarily installed in a position near the outer peripheral surface of the circumferentially required portion in a posture toward the rotation center of the blanket roll 20 and at a predetermined distance from the rotation center of the blanket roll 20. An electrostatic capacity displacement meter 26 serving as a displacement meter for the operation, and the linear scale 18, an encoder 24 directly connected to the other rotating shaft 21 b of the blanket roll 20, and the electrostatic capacity displacement meter 26. The offset printing apparatus according to the present invention is provided with a controller 27 for giving a command to the drive device 17 for the plate table 14 and the printing object table 16 and the rotation drive motor 23 for the blanket roll 20 based on the input signal. Configure.

  More specifically, as shown in FIGS. 2 and 3, the transfer mechanism section 19 includes columns 29 having required height dimensions on both the left and right outer sides of the intermediate portion in the longitudinal direction of the guide rail 12, respectively. Two beam members 30 are provided in the longitudinal direction (X-axis direction) 12 at predetermined intervals, and the tops of the columns 29 are integrally formed by beam members 30 arranged so as to cross above the required dimensions of the guide rail 12. A gate-shaped frame 28 is provided.

  Further, the roll support frame 22 is configured by integrally connecting a pair of left and right bearing housings 31a and 31b with a connecting member 32 extending in the left and right direction, and the left and right bearing housings 31a and 31b are connected to the blanket roll 20. The left and right bearing housings 31a and 31b are respectively arranged on the left and right outer sides of the guide rail 12 in the frame 28. It is arranged between two columns 29 arranged at positions along the X-axis direction, and is attached to each column 29 via a linear guide 34 in the vertical direction so as to be movable in the vertical direction.

  Further, as an elevating drive mechanism 25 for elevating and driving the blanket roll 20 integrally with the roll support frame 22, the beam members 30 of the frame 28 are directly above the left and right bearing housings 31a and 31b of the roll support frame 22. The following ball screw mechanisms 25 (for the sake of convenience, the same reference numerals as those of the elevating drive mechanism 25 are provided) are provided respectively.

  Specifically, each of the ball screw mechanisms 25 is capable of rotating a portion near the upper end via a bearing 36 at a position directly above the left and right bearing housings 31a and 31b of the roll support frame 22 in the beam member 30. An individual gear box 37 connected to the held screw shaft 35 in the vertical direction and a projecting end portion provided at a required position on the upper side of the beam member 30 and projecting upward from the bearing 36 of each screw shaft 35. And a lift drive motor 38 such as a servo motor connected to each gear box 37, and an individual nut member 39 screwed into the lower part of each screw shaft 35. Further, each nut member 39 of each ball screw mechanism 25 is configured to be attached to the upper side of each bearing housing 31a, 31b of the roll support frame 22 via a required mounting member 40. As a result, each screw shaft 35 is rotationally driven through each gear box 37 by the operation of each lifting drive motor 38, thereby lifting and lowering the roll support frame 22 integral with each nut member 39, The blanket roll 20 held on the roll support frame 22 can be moved up and down.

  Each bearing 36 can be supported by receiving a thrust load acting on each screw shaft 35 from the roll support frame 22 via each nut member 39 screwed to the lower portion of each screw shaft 35. It shall be.

  The range of the blanket roll 20 that is raised and lowered by the ball screw mechanism 25 via the roll support frame 22 is such that the lower end of the outer peripheral surface of the blanket roll 20 extends along the guide rail 12 on the gantry 11. The outer periphery of the blanket roll 20 from the retreat height position where the plate 13 held on the traveling plate table 14 and the surface of the printing target 15 held on the printing target table 16 are separated from the surface by a required dimension. The lower end of the surface has a range up to a height position slightly below the position where the lower surface of the plate 13 held on the plate table 14 or the surface of the printing target 15 held on the printing target table 16 contacts. It is assumed that it is set as follows.

  A reduction gear 41 connected to the rotation drive motor 23 is attached to the outside of one bearing housing 31a of the roll support frame 22, and an output shaft (not shown) of the reduction gear 41 is connected to the one bearing housing 31a. It is connected to one rotating shaft 21a of the held blanket roll 20.

  Further, the encoder 24 is attached to the outside of the other bearing housing 31b of the roll support frame 22, and the unillustrated input shaft of the encoder 24 holds the blanket roll 20 held by the other bearing housing 31b. The other rotary shaft 21b is connected directly and integrally to the end axial center position. As a result, the blanket roll 20 can be driven to rotate at a required rotational speed via the speed reducer 41 by the operation of the rotation drive motor 23. At this time, the encoder 24 causes the blanket roll 20 to rotate. The rotation angle with respect to a certain position in the circumferential direction can be accurately measured in a state that does not include errors due to torsional deformation of mechanical parts and errors due to gear backlash. Therefore, the angular velocity of the rotating blanket roll 20 can be detected with high accuracy based on the signal from the encoder 24.

  The capacitance displacement meter 26 is, for example, in the vicinity of the lower end portion of the outer peripheral surface of the blanket roll 20 that is directly below the rotation center of the blanket roll 20, the direction of the rotation center of the blanket roll 20, That is, it is arranged directly above, and in this state, it is detachably attached to a required portion of the roll support frame 22 via a temporary attachment member 42. As a result, in a state where the capacitance displacement meter 26 is attached to the roll support frame 22 via the temporary attachment member 42, the capacitance displacement meter 26 is held by the roll support frame 22. The blanket roll 20 can be fixed at a position separated from the rotational center of the blanket roll 20 by a certain distance L, and the capacitance-type displacement meter 26 can be used to remove the blanket from the capacitance-type displacement meter 26. The distance m to the portion immediately below the center of rotation on the outer peripheral surface of the roll 20 can be measured.

  On the other hand, by removing the temporary attachment member 42 from the roll support frame 22, the capacitive displacement meter 26 can be removed together and removed.

  As shown in FIG. 4, the controller 27 outputs detection signals for the table positions in the X-axis direction of the plate table 14 and the printing target table 16 input from the linear scale 18 provided on the gantry 11. Based on this, a command is given to the individual drive devices 17 of the plate table 14 and the printing target table 16, and the position, the moving direction (traveling direction) of each of the tables 14, 16 and the moving speed as the moving amount per unit time. A detection signal of the rotational angle of the blanket roll 20 input from the table traveling control unit 27a capable of controlling (traveling speed) and the encoder 24 directly connected to the other rotation shaft 21b of the blanket roll 20 in the transfer mechanism unit 19. On the basis of the angular velocity (rotation) of the blanket roll 20 by giving a command to the drive motor 23 for rotation of the blanket roll 20. And a roll rotation controller 27b which is adapted degrees) and can control the angle and orientation, it is constituted that can be controlled synchronously above, the table travel control unit 27a and the roll rotation controller 27b.

  Further, the controller 27 is rotated by the function of the roll rotation control unit 27b when the capacitive displacement meter 26 is attached to the roll support frame 22 via the temporary attachment member 42. The blanket roll 20 can be rotated by giving a command to the drive motor 23. In this state, the rotation angle detection signal of the blanket roll 20 input from the encoder 24 and the capacitance type The blanket roll 20 is provided on the basis of a measurement signal of a distance m from the capacitance type displacement gauge 26 input from the displacement gauge 26 to a portion immediately below the rotation center on the outer peripheral surface of the blanket roll 20. The value of the distance m input from the capacitance displacement meter 26 when the rotation angle is reached is the same as described above. By subtracting from the value of the distance L from the rotation center of the ballet roll 20 to the capacitance type displacement meter 26, the blanket roll 20 is rotated from the rotation center of the blanket roll 20 to the outer peripheral surface when the blanket roll 20 has the certain rotation angle. An apparent radius r up to a portion immediately below the center of rotation can be calculated. Further, the calculated apparent radius r from the center of rotation of the blanket roll 20 to a peripheral position immediately below the calculated radius r is calculated as described above. A function of temporarily storing the blanket roll 20 in a database (not shown) in association with the rotation angle of the blanket roll 20 is provided.

  Furthermore, the controller 27 is a plate held on the plate table 14 on which the transfer mechanism unit 19 travels along the guide rail 12 in a state in which the capacitive displacement meter 26 is removed together with the temporary attachment member 42. 13 and the printing object 15 held on the printing object table 16 are sequentially brought into contact with the blanket roll 20 from above while rotating the blanket roll 20 to transfer (accept) from the plate 13 to the blanket roll 20, and from the blanket roll 20 When a rotation angle detection signal of the blanket roll 20 input from the encoder 24 is input when performing retransfer (printing) to the printing object 15, the rotation angle is determined according to the detected rotation angle. The apparent value of the radius r from the rotation center of the blanket roll 20 to the circumferential position immediately below it is obtained from the above database. The value of the apparent radius r at the rotation angle and the product of the angular velocity of the blanket roll 20 detected based on the signal input from the encoder 24 are directly below the rotation center of the blanket roll 20. , That is, the amount of circumferential movement per unit time at the lower end of the outer peripheral surface of the blanket roll 20 that is in contact with the surface of the plate 13 on the plate table 14 or the surface of the printing target 15 on the printing target table 16 Is calculated, and the calculated peripheral speed is synchronized with the movement speed, which is the movement amount per unit time of the plate 13 and the printing target 15 as the plate table 14 and the printing target table 16 travel. As described above, a command for correcting the drive amount is given to one or both of the drive motor for rotation 23 of the blanket roll 20 and the drive device 17 of the tables 14 and 16. Some as having the function.

  The offset printing apparatus according to the present invention requires one end in the longitudinal direction of the guide rail 12 at a position corresponding to one end in the longitudinal direction of the guide rail 12 on the mount 11 as shown in FIG. A plate table standby area 43 is provided, which allows the plate table 14 to be moved to a certain level and waits, and the plate 13 held on the plate table 14 to be exchanged, and the plate table standby on the gantry 11 is provided. An inking device 44 for inking the plate 13 held on the plate table 14 is provided between the area 43 and the transfer mechanism unit 19, and the guide rail on the mount 11 is further provided. The table to be printed 16 is moved to the other end in the longitudinal direction of the guide rail 12 at a position corresponding to the other end in the longitudinal direction of the guide 12 and waits. In the state, it is assumed that a constitution comprising a printed installation area 45 for performing the removal of printed 15 after printing and mounting of a new printing target 15 relative to the print target table 16.

  When performing offset printing using the offset printing apparatus of the present invention having the above-described configuration, first, before starting the printing operation, the capacitance displacement meter 26 is temporarily installed on the roll support frame 22. With the attachment member 42 attached, the blanket roll 20 is rotated as described above, and the controller 27 causes the rotation angle of the blanket roll 20 and the rotation center of the blanket roll 20 to be directly below the rotation center. Data relating to the correlation with the apparent radius r up to the circumferential position is temporarily stored in the database.

  Subsequently, the electrostatic capacitance type displacement meter 26 and the temporary attachment member 42 are removed, and then the plate table 14 holding the plate 13 inked by the inking device 44 is sent to the transfer mechanism unit 19 and rotated. The blanket roll 20 is brought into contact with the plate 13 on the traveling plate table 14. At this time, according to the rotation angle of the blanket roll 20 detected by the encoder 24 by the controller 27, the appearance from the rotation center of the blanket roll 20 to the lower end of the outer peripheral surface in contact with the plate 13 is apparent. The peripheral speed of the lower end portion of the outer peripheral surface of the blanket roll 20 is calculated by the product of the upper radius r and the angular velocity of the blanket roll 20 detected based on the signal input from the encoder 24. One or both of the rotational speed of the blanket roll 20 and the moving speed of the plate 13 on the plate table 14 are controlled so that the peripheral speed and the moving speed of the plate 13 on the plate table 14 are synchronized. become. As a result, the peripheral speed of the blanket roll 20 and the moving speed of the plate 13 are precisely synchronized, so that the printing pattern is transferred from the plate 13 to the blanket roll 20 with high accuracy. It comes to be.

  Thereafter, the printing object table 16 holding the printing object 15 is sent to the transfer mechanism 19, and printing on the printing object table 16 is caused to run in the same direction as the plate table 14 is passed during the transfer process. The rotating blanket roll 20 is brought into contact with the object 15. At this time, similarly to the transfer step, the controller 27 contacts the printing object 15 from the rotation center of the blanket roll 20 according to the rotation angle of the blanket roll 20 detected by the encoder 24. The peripheral speed of the lower end portion of the outer peripheral surface of the blanket roll 20 is determined by the product of the apparent radius r to the lower end portion of the outer peripheral surface and the angular velocity of the blanket roll 20 detected based on the signal input from the encoder 24. The rotational speed of the blanket roll 20 and the print target 15 on the print target table 16 are synchronized so that the calculated peripheral speed and the movement speed of the print target 15 on the print target table 16 are synchronized. One or both of the movement speeds are controlled. As a result, since the peripheral speed of the blanket roll 20 and the moving speed of the printing object 15 are precisely synchronized, the printing pattern is transferred from the blanket roll 20 to the printing object 15 with high accuracy. To be done.

  Therefore, even if the blanket roll 20 has a non-uniform apparent radius from the rotation center to the circumferential position due to eccentricity or the like, the printing pattern of the plate 13 can be highly reproducible to the printing object 15. Can be printed. Therefore, it is possible to perform high-precision printing for a very fine print pattern that is required to suppress the positional deviation of the print position to several μm, such as an electrode pattern.

  Next, FIG. 5 shows another embodiment of the present invention. In the same configuration as that shown in FIGS. 1 to 4, the capacitance type displacement meter 26 is placed at the center of rotation of the blanket roll 20. Instead of a configuration in which the blanket roll 20 is disposed immediately below the lower end of the outer peripheral surface of the blanket roll 20 and is detachably attached to the roll support frame 22 via a temporary attachment member 42, a capacitance type A required position where the displacement meter 26 does not interfere when the blanket roll 20 is brought into contact with the plate 13 on the plate table 14 or the printing target 15 on the printing target table 16, for example, near the outer peripheral surface of the side portion of the blanket roll 20. At the position, the blanket roll 20 is arranged in the direction of the center of rotation of the blanket roll 20, and the capacitance type displacement meter 26 is attached to the required number of the roll support frame 22 via the mounting member 46. It is obtained as attached to.

  As described above, the capacitance type displacement meter 26 is disposed in the vicinity of the outer peripheral surface of the side portion of the blanket roll 20, so that the distance between the capacitance type displacement meter 26 and the center of rotation of the blanket roll 20. L is a constant value. The capacitance displacement meter 26 measures the distance m to the outer peripheral surface of the blanket roll 20 along a straight line connecting the capacitance displacement meter 26 and the rotation center of the blanket roll 20. It becomes like this.

  Therefore, the distance m from the distance L between the capacitance type displacement meter 26 and the rotation center of the blanket roll 20 to the outer peripheral surface of the blanket roll 20 measured by the capacitance type displacement meter 26 by the controller 27. , The apparent radius r of the blanket roll 20 at the circumferential position along the straight line connecting the capacitance displacement meter 26 and the rotation center of the blanket roll 20 is calculated.

  In view of this, in the present embodiment, the controller 27 detects the rotation angle of the blanket roll 20 input from the encoder 24 while the blanket roll 20 is rotated by the function of the roll rotation control unit 27b. Based on the signal and the measurement signal of the distance m to the predetermined location on the outer peripheral surface of the blanket roll 20 input from the capacitance displacement gauge 26, the rotation of the capacitance displacement gauge 26 and the blanket roll 20 is performed. The apparent radius r of the blanket roll 20 at the circumferential position along the straight line connecting the center is calculated, and the calculated apparent radius r is associated with the rotation angle of the blanket roll 20 at that time. And once stored in a database (not shown), and then, as the blanket roll 20 rotates, the blanket roll 20 A signal inputted from the encoder 24 that a portion arranged on a straight line connecting the capacitance type displacement meter 26 and the rotation center of the blanket roll 20 on the peripheral surface reaches the lower end of the blanket roll 20. , The controller 27 calls the apparent radius r once stored in the database, and detects it based on the apparent radius r and a signal input from the encoder 24. By calculating the product of the angular velocity of the blanket roll 20 and calculating the peripheral speed, which is the circumferential movement amount per unit time of the lower end of the outer peripheral surface of the blanket roll 20, the calculated peripheral speed and the plate table 14 or The blanket roll 20 so that the movement speed, which is the movement amount per unit time, of the plate 13 and the printing object 15 accompanying the traveling of the printing object table 16 is synchronized. A rotation drive motor 23, there as having a function of providing an instruction to correct the driving amount to one or both of the drive unit 17 of the respective tables 14, 16.

  Other configurations are the same as those shown in FIGS. 1 to 4, and the same components are denoted by the same reference numerals.

  According to the present embodiment, when the rotating blanket roll 20 is brought into contact with the plate 13 on the plate table 14 or the printing target 15 on the printing target table 16 in the transfer mechanism unit 19, A blanket roll 20 at a circumferential position at a certain position on the outer peripheral surface passes through a portion where the capacitance displacement meter 26 is installed before a time required to come into contact with the plate 13 or the printing object 15. The apparent radius r from the rotation center of the sheet can be obtained in advance, and when the portion contacts the plate 13 or the printing object 15, the apparent radius r obtained in advance with respect to the circumferential position of the portion The rotational speed of the blanket roll 20 so that the peripheral speed derived from the product of the angular speed of the blanket roll 20 and the moving speed of the plate 13 or the printing object 15 are synchronized. By controlling one or both of the moving speeds of the plate 13 on the plate table 14, the peripheral speed of the blanket roll 20 and the moving speed of the plate 13 and the printing object 15 are precisely synchronized. Therefore, the printing pattern can be transferred from the plate 13 to the blanket roll 20 with high accuracy, and the printing pattern can be transferred from the blanket roll 20 to the printing object 15 with high accuracy. it can.

  Therefore, the effect similar to the said embodiment can be acquired also by this Embodiment.

  Note that the present invention is not limited to the above-described embodiment, and as the displacement meter, it is preferable to use the capacitive displacement meter 26 from the viewpoint of resolution. Any type of displacement meter may be used as long as it can detect the distance.

  The location where the displacement meter is installed may be changed as appropriate as long as the distance from the outer peripheral surface of the blanket roll 20 can be measured.

  As the raising / lowering drive mechanism of the blanket roll 20 in the transfer mechanism unit 19, a mechanism other than the ball screw mechanism 25 may be used.

  The inking device 44 may use any type of inking device 44 as long as appropriate inking can be performed on the plate 13 held on the plate table 14.

  The offset printing apparatus of the present invention may be applied to perform printing on any print target 15 other than the substrate.

  Of course, various modifications can be made without departing from the scope of the present invention.

DESCRIPTION OF SYMBOLS 11 Base 12 Guide rail 13 Plate 14 Plate table 15 Print target 16 Print target table 20 Blanket roll 21a, 21b Rotating shaft 23 Rotation drive motor 24 Encoder 26 Capacitive displacement meter (displacement meter)
27 Controller r Apparent radius

Claims (4)

  While the blanket roll is rotated by the drive motor for rotation, the blanket roll is brought into contact with the plate held on the plate table running on the guide rail on the gantry from above, and then the rotated blanket roll is moved to the guide rail. Offset printing that causes the printing object held on the printing object table running above to contact the printing object from above so that transfer from the plate to the blanket roll and retransfer from the blanket roll to the printing object are performed. In the method, the correlation between the rotation angle of the blanket roll and the apparent radius from the rotation center to the circumferential position of the blanket roll is obtained in advance and stored in a database, and the blanket roll is rotated on the plate table. When making contact with the printing object on the printing plate and the printing object table, Based on the information on the rotation angle of the ket roll, the apparent radius from the rotation center of the blanket roll to the portion in contact with the plate or the printing object is called from the database, and the called apparent rotation radius and the above The blanket roll plate guided by the product of the angular velocity of the rotating blanket roll and the peripheral speed of the portion in contact with the printing object, the movement speed of the plate by the traveling of the plate table, and the traveling of the printing object table An offset printing method characterized by synchronizing the movement speeds of printing objects.   The rotation angle of the blanket roll is detected by an encoder directly connected to an end face of a rotation shaft opposite to a rotation shaft connected to a rotation drive motor among rotation shafts at both ends of the blanket roll. The offset printing method described.   A plate table and a printing target table that run on the guide rails on the gantry are provided, and a plate held on the plate table and a blanket roll that is lifted and lowered by a lifting drive mechanism are rotated on the printing target held on the printing table. In the offset printing apparatus in which the transfer from the plate to the blanket roll and the retransfer from the blanket roll to the printing object are performed by sequentially contacting from above while being rotated by the drive motor for the blanket. A displacement meter for measuring the distance from the outer peripheral surface of the blanket roll is provided at a required location away from the outer periphery of the roll, and an encoder for detecting the rotation angle of the rotating blanket roll is provided. Based on the signal input from the encoder, the rotation angle of the blanket roll And a function of preliminarily obtaining a correlation between the apparent radius from the rotation center of the blanket roll to the circumferential position and storing it as data, and a plate on the printing table and a printing target table in a state where the blanket roll is rotated. Based on the information about the rotation angle of the blanket roll input from the encoder when contacting each printing object, from the stored data to the part in contact with the plate or printing object from the rotation center of the blanket roll The blanket roll plate and the printing object are in contact with the product of the called apparent radius and the angular velocity of the blanket roll detected based on the signal input from the encoder. Function for obtaining the peripheral speed of the part, the obtained peripheral speed of the blanket roll and the plate by running the plate table Offset printing apparatus characterized by having a configuration in which the moving speed of the moving speed and printed by the running of the printing medium table comprising a control unit having a function to synchronize respectively.   An encoder for detecting the rotation angle of the blanket roll is provided by being directly connected to the end surface of the rotation shaft opposite to the rotation shaft connected to the rotation drive motor among the rotation shafts at both ends of the blanket roll. Item 4. The offset printing apparatus according to Item 3.

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