JP2002019080A - Offset printer, method for mounting blanket to offset printer and image forming apparatus manufactured by offset printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that uniformity of tensions applied to right and left ends of a blanket in a winding advancing direction cannot be guaranteed due to a difficulty of winding in a uniform thickness caused by a difficulty of accurately matching a winding amount of a cylinder to a feeding amount of a table in the case of winding the blanket on a blanket cylinder of an offset printer. SOLUTION: A tension applied to the blanket 207 is controlled in a rotation of the blanket cylinder 208 and a movement of the table 202 in a master and slave relationship so as to maintain a predetermined tension while monitoring the tension applied to the blanket 207 by a monitor 405. For example, the tension is finely regulated with the table 202 as the slave. When tension sensors 405 (401) are provided at right and left sides of a centerline of the winding direction (a direction Y) of the blanket, the tensions applied to the right and left sides can be made uniform. This printer can be accurately printed in a pattern even on a base having a large area to be adapted to manufacture the image forming apparatus.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-precision transfer of a circuit pattern or the like formed on a printing intaglio (hereinafter abbreviated as "plate") onto a substrate (hereinafter referred to as a "work") via a blanket. The present invention relates to an offset printing apparatus for forming a print, a blanket mounting method in the apparatus, and an image display apparatus using a circuit pattern transferred and formed by the apparatus.

[0002]

2. Description of the Related Art In recent years, a thin flat plate-shaped image forming apparatus has attracted attention as an image forming apparatus replacing a large and heavy cathode ray tube. Although a liquid crystal display device has been actively researched and developed as a flat plate image forming device, there still remain problems such as a dark image, a narrow viewing angle, and difficulty in increasing the screen size.

As a substitute for the liquid crystal display device, there is a self-luminous display, that is, a display using an electron-emitting device such as a plasma display, a fluorescent display tube, and a surface conduction electron-emitting device. A self-luminous display can obtain a brighter image and has a wider viewing angle than a liquid crystal display device. On the other hand, recently, a cathode ray tube having a screen display section of 30 inches or more has become common, and further increase in size is desired. However, it is hard to say that increasing the size of a CRT is appropriate due to the increase in installation area and weight. Therefore, a self-luminous flat display is suitable for realizing a bright image, a wide viewing angle equivalent to a CRT, and a reduction in installation area and weight as compared with a CRT.

The applicant of the present invention has proposed an image forming apparatus using electron-emitting devices, among self-luminous type flat plate image forming apparatuses, particularly an M.P. Elinson et al. [Radio. Eng. Electr
on. Phys. , 10, 1290, (1965)] Attention is paid to an image forming apparatus using a surface conduction electron-emitting device.

The surface conduction electron-emitting device emits electrons by passing a current through a small-area thin film formed on a substrate in parallel with the film surface. Examples of the surface conduction electron-emitting device include a device using an SnO ₂ thin film by Elinson et al. And a device using an Au thin film [G. Dittmer: T
Hin Solid Films, 9, 317 (197)
2)], an In ₂ O ₃ / SnO ₂ thin film [M. H
artwell and C.I. G. FIG. Fonstad: I
EEE Trans. ED Conf. , 519 (19
75)], using a carbon thin film [Hisashi Araki et al .: Vacuum,
26, No. 1, p. 22 (1983)].

As a typical example of these surface conduction electron-emitting devices, the above-mentioned M.S. Figure 11 shows the Hartwell device configuration.
Is shown schematically in FIG. In the figure, reference numeral 1101 denotes a substrate.
Reference numeral 1104 denotes a conductive thin film, which is formed of a metal oxide thin film or the like formed by sputtering in an H-shape. The device electrode interval L in the figure is 0.5 to 1 mm, W '
Is set at 0.1 mm.

[0007] Further, the present applicant has previously disclosed in US Pat.
No. 6,833, proposes a surface conduction electron-emitting device in which fine particles for emitting electrons are dispersed and arranged between a pair of device electrodes. This electron-emitting device can control the electron-emitting position more precisely than the conventional surface conduction electron-emitting device. FIG. 12 shows a typical configuration of the surface conduction electron-emitting device. FIG. 12A is a plan view of the device, and FIG.
(B) shows a sectional view. In the figure, reference numeral 1201 denotes an insulating substrate, 1202 and 1203 denote element electrodes for obtaining electrical connection, and 1104 denotes a conductive thin film made of finely divided conductive material. In this surface conduction electron-emitting device, the interval L between the device electrodes 1202 and 1203 is 0.01 μm.
-100 μm, electron emission portion 1105 of conductive thin film 1104
Is suitably 1 × 10 ⁻³ Ω / □ to 1 × 10 ⁻⁹ Ω / □. The element electrode has a thickness d of 20 to maintain electrical connection with the thin film 1104 made of fine particle conductive material.
It is desirable to form the thin film to 0 nm or less.

The present inventor is studying an increase in the area of an image forming apparatus in which a large number of the surface conduction electron-emitting devices are arranged on a substrate. Various methods are conceivable for producing an electron source substrate in which an electron-emitting device and a wiring are arranged on a substrate. One of the methods is to produce all of the device electrodes and the wiring by a photolithography method.

[0009] On the other hand, a method is conceivable in which the surface conduction electron-emitting device and the electron source substrate including the same are produced by using a printing technique such as screen printing or offset printing.
The printing method is suitable for forming a pattern on a large area,
By forming the device electrodes by a printing method, it becomes possible to form a large number of surface conduction electron-emitting devices on a substrate. It is also advantageous in terms of cost. In forming element electrodes by a printing method, an offset printing technique suitable for forming a thin film is suitable. An example in which the offset printing technique is applied to a circuit board is disclosed in Japanese Patent Application Laid-Open No. 4-290295. The substrate disclosed in this publication has a plurality of bonding electrodes connected to circuit components at different angles in order to eliminate bonding defects due to variations in electrode pitch dimensions due to pattern expansion and contraction during printing. . The publication describes that an electrode pattern is formed by offset printing.

Hereinafter, a general offset printing apparatus and a printing method for forming an electrode pattern, a color filter, and the like will be described. However, in order to make the description easy to understand, in this description, a printing plate is simply abbreviated as a plate and has the same meaning, and a printing material is synonymous with a work. The work is typically a glass plate.

FIG. 2 is a schematic configuration diagram of a flatbed proofing machine type offset printing apparatus. In this apparatus, printing proceeds in the following number order. The blanket cylinder 208 has a blanket 207 wound around the outer periphery thereof in advance and is mechanically fixed (the fixed portion is omitted in FIG. 2).
1 is rotated by the blanket cylinder drive servomotor 206 around the center. The amount of rotation is at least the blanket 207 over the entire area of the plate 203 and the work 213 described below.
Is in the contact area. The plate 203 and the work 213
It is assumed that when is passed under the blanket 207, the blanket 207 and the plate 203 and the work 213 have a height positional relationship where an appropriate pressure is applied.

(1) A plate surface table (hereinafter referred to as “table”) 202 fixedly disposed on a linear slider (not shown) that is freely controlled in the Y-axis direction by a slider drive motor (not shown). The plate 203 is installed with the end faces thereof aligned with the plate positioning portions 204 and 205, and fixed at a fixed position on the table 202 by, for example, a vacuum mechanism provided in the table 202.

(2) As shown in FIG. 3A, the table 202 is moved by the table driving motor 201 to a position where the plate 203 reaches the lower part of the inking mechanism 214 (a position just before the concave pattern), and the inking mechanism is moved there. An appropriate amount of ink 215 is discharged onto the plate 203 from 214. The inking mechanism 214 is normally moved linearly by a slider in the X-axis direction in FIG. 2 (parallel to the blanket cylinder shaft 211).

(3) As shown in FIG. 3 (b), the flat blade-shaped ink doctor 209 is turned around the ink doctor shaft 212 and stopped at a position where an appropriate pressure is applied to the plate 203. After that, when the plate 203 is moved by the slider drive motor 201, the ink is
3, the ink on the surface of the plate is scraped off by the ink doctor 209, so that the ink remains only in the concave portions of the plate 203.

(4) Next, as shown in FIG. 3C, the ink doctor 209 is returned to the standby position. Next, blanket cylinder 20
The control rotation is performed by the servo motors 206 and 201 so that the clockwise rotation of 8 and the movement of the plate 203 in the left (+ Y) direction are completely synchronized. The pressure of the contact surface generated at this time causes
The ink for the three concave portions is transferred to the blanket 207. This is called "acceptance", and the generated pressure is called "acceptance pressure". The reception is completed when the plate 203 has passed under the blanket cylinder 208, and the plate 203 is removed, and the table 202 and the blanket cylinder 208 are returned to the position shown in FIG.

(5) The work 213 is fixed at a fixed position on the table 202 in the same manner as in the case of the plate. Next, FIG.
As described above, the servo motors 206 and 201 control and drive the clockwise rotation of the blanket cylinder 208 and the movement of the work 213 in the left (+ Y) direction completely in the same manner as in the reception. The pressure of the contact surface generated at this time causes blanket 2
07 is transferred to the work 213. This is called "transition", and the generated pressure is called "transition pressure". The transfer is completed when the work 213 has passed below the blanket cylinder 208, and the offset printing is completed.

The ink can be appropriately selected depending on the function of the pattern to be produced. That is, an ink containing an organic Au compound called an Au resinate paste is mainly used for an electrode pattern such as a recording thermal head, and R, G, and B colors are used for a color filter used in a liquid crystal display device or the like. An ink in which a pigment is dispersed, an ink containing an organic dye, and the like are used.

[0018]

In general, there are the following problems in increasing the area of the screen of a flat panel display. In an electronic circuit processing process of a thin-film image forming device in a simple matrix liquid crystal display device (LCD), a thin film transistor liquid crystal display device (TFT / LCD), a multi-electron source flat CRT, and the like, a functional thin film is formed on a workpiece. Pattern processing is performed. For example,
After forming the AI material on the substrate, a wiring pattern is formed by photolithography and etching.

However, for example, when a fine pattern is manufactured on a large substrate of 40 cm square or more by photolithography, a large-sized apparatus including a large-sized exposure apparatus is required, and an enormous cost is required. Further, unlike an exposure apparatus for a silicon semiconductor, an exposure apparatus for a large area substrate has manufacturing problems such as a reduction in resolution and an increase in processing time per substrate. In addition, handling during a process step becomes difficult, and it is not easy to form an electron-emitting device and a wiring on a large-area substrate. Furthermore, performing high-precision photolithography on a large-area substrate of about 1 m has a disadvantage that it is difficult to increase the size of the manufacturing apparatus itself, and that the manufacturing cost becomes enormous.

On the other hand, in the process of processing an electronic circuit using a thick film such as a plasma display (PDP) display device, a conductive paste or an insulating paste is directly printed by pattern printing using a screen printing method, and then fired by electrode firing. A method of forming a pattern or an insulating layer has been adopted. Patterning by the printing method can be applied to a relatively large-area substrate, and the processing time per substrate is shorter than that of the photolithography technique.

However, when the resist ink, conductive paste, or insulating paste is transferred from the printing plate to the substrate, the screen plate is deformed, and the printed pattern is easily deformed.
There is a limit to the pattern accuracy.

The present inventors are studying a large area offset printing method in order to solve the above-mentioned problems of the apparatus cost, the manufacturing cost, and the wiring accuracy in order to increase the area of the screen of the flat panel image display apparatus. One of the important factors that determine the print quality of offset printing is the pressure during printing (printing pressure), that is, the receiving pressure and the transfer pressure described in the related art (hereinafter, referred to as the transfer pressure).
Accepting pressure and transition pressure are collectively referred to as "printing pressure").

However, as the area of the blanket 207 increases, the uniformity of the thickness of the blanket 207 is reduced by the tension applied to the blanket cylinder 208. And the print quality tends to deteriorate. Further, since the blanket 207 is a consumable part and needs to be periodically replaced, a blanket winding technique capable of realizing an arbitrary and constant blanket tension with high reproducibility has been demanded.

Conventionally, a blanket winding control method for a blanket cylinder is disclosed in Japanese Patent Application Laid-Open No. H11-010835. The outline of this prior art is based on the following procedure.

(1) Blanket 207 shown in FIG.
Is fixed to the fixing portion 103 of the blanket cylinder 208, and the other end of the blanket 207 is locked to the locking portion 102 of the table 202 having the tension detector 405.

(2) Referring to FIG.
The blanket 207 is moved in the Y direction to extend to a desired winding tension.

(3) From the state of FIG. 1B, the table 202 is controlled by the servomotor 201 and the servomotor 206.
The amount of movement of the blanket cylinder 208 and the amount of rotation of the blanket cylinder 208 are synchronized, and the blanket 207 is wound around the blanket cylinder 208 via the state of FIG.

(4) Blanket 207 in FIG.
Is fixed to the fixing portion 104 and the other end is removed from the locking portion 102 to complete the winding.

In the above prior art, the winding operation is performed while synchronizing the amount of movement of the table 202 and the amount of rotation of the blanket cylinder 208. However, in the actual winding operation, there are the following problems.

The outer peripheral distance of the blanket cylinder 208 differs between the calculated value on the desk and the actual value depending on the allowable processing accuracy of the blanket cylinder 208. This absolute difference amount becomes large due to the increase in the diameter of the blanket cylinder 208 accompanying the enlargement of the printing area.

In addition, with the increase in printing area, blanket 2
07 increases in size, and the required tension at the time of expanding the blanket increases in proportion to this. Due to an increase in the size of the apparatus for this purpose, an error in the mechanical precision error or an increase in the amount of mechanical deformation increases the error between the commanded movement amounts of the motors 201 and 206 and the absolute movement amounts of the blanket locking 102 position and the fixed 103 position.

In the above situation, since the blanket 207 is almost rigid in the extension direction, in order to maintain the tension at the time of FIG. 1B during the entire process up to FIG. The tuning position accuracy of less than 100 microns is required, but due to the enlargement of the device due to the enlargement of the printing area, the movement amount calculation coefficient of the mechanical system, the outer periphery processing accuracy of the cylinder, the ball screw pitch accuracy, the mechanical backlash and other factors It is difficult to match the amount of winding of the cylinder from the start of winding to the end with the amount of feeding of the table with high accuracy. That is, the tension cannot be guaranteed, and the blanket may be loosened or over-pulled. As a result, winding of a uniform thickness cannot be guaranteed. The fact that it is very difficult to achieve this is the first problem of the prior art.

In particular, when the winding of the blanket cylinder 208 is excessive, unless the abnormality is detected and stopped, the blanket 207 may be broken. Further, even if the operation is stopped after being detected as abnormal, the operation of calculating parameters such as coefficients becomes enormous in order to secure tuning accuracy.

Next, FIG. 5 shows a conceptual diagram of a tension vector during a blanking step of a conventional blanket 207 using one tension detector 405. At this time, [vector 501 = vector 502 + vector 503] holds, but [vector 5
02 = vector 503] does not always hold, and the uniformity of the tension at the left and right ends in the tension traveling direction of the substantially rigid blanket 207 is very likely to be impaired. The second problem of the prior art is that the winding operation is completed without detecting this abnormality, and the right and left winding tensions cannot be guaranteed in the winding progress direction.

[0035]

Means and Functions for Solving the Problems The present inventor has provided:
Either the control motor 201 of the table 202 or the control motor 206 of the blanket cylinder 208 is set as a main shaft and the other is set as a slave shaft. During winding work of the blanket 207, the slave shaft performs control to guarantee tension. It has been found that the first problem can be solved.

Also, at least one tension detecting mechanism is used on both sides with respect to the center line in the winding direction of the blanket 207, and the tension is constantly monitored during the tension applying and winding operations, and the operation is interrupted when an abnormality occurs. Has found that the second problem can be solved.

That is, according to the blanket mounting method of the present invention, there is provided an offset printing apparatus in which a plate and a work are slid in contact with a blanket mounted on an outer peripheral surface of a rotating blanket cylinder by moving a table on which the plate and the work are mounted. A method of mounting a blanket on a blanket cylinder, comprising: a first fixing step of fixing one end of the blanket to a first fixing portion of the blanket cylinder; and a locking step of locking the other end of the blanket to a locking portion of a table. When,
The blanket cylinder extends the blanket from its natural length to a length where a predetermined tension is applied by moving the table away from the blanket cylinder in a fixed state, and based on the output signal while monitoring the tension applied to the blanket during that time. Controlling the amount of movement of the table, a tension applying step, winding the blanket around the blanket cylinder by rotating the blanket cylinder and moving the table closer to the blanket cylinder,
A winding step of controlling the rotation of the blanket cylinder and the movement of the table in a master-slave relationship so as to maintain the predetermined tension applied based on the output signal while monitoring the tension applied to the blanket during the blanking; And fixing the vicinity of the other end to the second fixing portion of the blanket cylinder while maintaining the predetermined tension. Then, usually, after the second fixing step, a lock releasing step of removing the other end of the blanket from the locking portion of the table is performed.

In a preferred embodiment of the blanket mounting method of the present invention, the monitoring of the tension in the tension applying step or the winding step is performed at a plurality of points on the blanket, and the points are located on both sides of the center line in the winding direction of the blanket. At least one each. Then, an average value of the detection values by the monitor at the plurality of locations can be used as the tension applied to the blanket. Further, when the mutual difference between the detection values obtained by the monitors at the plurality of locations exceeds a predetermined allowable range, it is determined that there is an abnormality, and the tension applying step or the winding step can be interrupted.

As another abnormality detection, in the tension applying step, the total length of the blanket is automatically recognized, and when the recognized numerical value exceeds a preset allowable range, it is determined that there is an abnormality, and the step can be interrupted. . Further, in the tension applying step or the winding step, when the process time exceeds a preset allowable range, the process can be regarded as abnormal and the process can be interrupted.

An offset printing apparatus according to the present invention is an offset printing apparatus in which a plate and a work are slid in contact with a blanket mounted on an outer peripheral surface of a rotating blanket cylinder by moving a table on which the plate and the work are mounted. The blanket cylinder has a first fixing portion for fixing one end of the blanket at the time of mounting the blanket onto the cylinder and after the mounting is completed, and a second fixing portion for fixing the other end of the blanket after the blanket mounting is completed. The table has a locking portion for temporarily fixing the other end of the blanket during the operation of mounting the blanket on the blanket cylinder; the offset printing apparatus further comprises a first servomotor for rotating the blanket cylinder; Servo motor to move vertically with respect to the blanket mounting work A tension sensor for monitoring the tension applied to the blanket, and the rotation amount of the blanket cylinder and the movement amount of the table during the blanket mounting operation are instructed to the first servomotor and the second servomotor based on the output signal from the tension sensor. Control means for performing
The operations of the first servomotor and the second servomotor are characterized in that they have a master-slave relationship so that the tension applied to the blanket during the blanket mounting operation becomes a predetermined value.

In a preferred embodiment, the offset printing apparatus according to the present invention includes at least one tension sensor on each side of a center line of the blanket in the winding direction. Then, the average value of the detection values of the plurality of tension sensors can be used as the tension applied to the blanket.
Further, when the difference between the detection values of the plurality of tension sensors exceeds a preset allowable range, it is determined that there is an abnormality, and the blanket mounting operation can be interrupted.

An image forming apparatus according to the present invention is manufactured by the offset printing apparatus according to the present invention. For example, a large number of surface conduction electron-emitting device electrodes are formed on an insulating substrate by the printing apparatus, and an image forming apparatus is manufactured using the obtained electron source substrate.

[0043]

Embodiment 1 FIG. 6 shows a general flowchart of the blanket mounting method, and FIGS. 7 to 9 show detailed flowcharts of some of the steps. It should be noted that the specific numerical values in the flowchart are examples for making the description easy to understand, and may be changed as appropriate in an actual apparatus.

First, the steps from the step of fixing and locking the blanket end to the step of applying tension (the step of applying an initial tension to the blanket 207) will be described with reference to FIG. (1) Set the fine tension correction pitch P2. Pitch P2
Is used for fine adjustment of tension at the end of the tension applying step, as described later. (2) One end of the blanket 207 is fixed to the fixing portion 103 of the blanket cylinder 208 and the other end is locked to the locking portion 102 of the member 101 of the table 202 as shown in FIG.
The movement of the member 101 in the + Y direction causes the tension detector 405 to move.
And 401 (load cell etc.) in FIG. 4 function. The fixing portion 103 and the locking portion 102 have a structure in which each end of the blanket 207 is pressed by an area in a direction perpendicular to the direction in which the blanket 207 is wound. (3) Blanket 2 immediately before the position shown in FIG.
Table 20 to the teaching point where 07 was a little loose
2 at the speed VS. (4) The table 202 is further moved at the speed V0 (VS >> V0) in the tensioning direction (-Y), and the blanket 20 is moved.
7 is gradually tensioned. During this time, the following (5) to (8) are checked. (5) Check the degree of unbalance of the tension values measured by tension detectors that are present on the left and right of the blanket 207 as shown by 405 and 401 in FIG.
If the difference exceeds a preset allowable value, it is determined that there is an abnormality, and the tension applying step ends. (6) The tension application time is checked, and if it exceeds a preset allowable value, it is determined that there is an abnormality, and the tension application process ends. (7) If the average value of the tension detected by the tension detectors 405 and 401 exceeds a preset allowable value, it is determined that there is an abnormality, and the tension applying step ends. (8) If the average tension value of the tension detectors 405 and 401 does not finally reach within the allowable range set for the target tension, the table 202 is moved in the further tension direction (−Y) of (4). At the speed V0 (VS >> V0). "
It returns to the operation and operates in a loop. If it reaches the allowable range, the movement of the table is stopped. (9) Proceed to the tension minute correction routine (see FIG. 9 for details). First, the start time of the minute tension correction routine is stored. (10) The average value Ta of the tension detectors 405 and 401 is obtained. (11) The table 202 is moved back and forth by only the pitch P2 (absolute amount) in the Y direction according to the comparison result of the average value Ta and the target tension value Tb. (12) Confirm completion of movement. (13) If the difference between the average value Ta and the target tension value Tb is not within the preset allowable range, the operation returns to the above-described operation (10) of “calculating the average value Ta of the tension detectors 405 and 401” and looping. Works like In the process of the loop, the abnormalities of the left and right tension imbalance, the tension application time over, the tension underage, and the tension excess are checked, and if an abnormality occurs, the tension application process is interrupted and terminated. If it is within the allowable range, the process proceeds to the next step and returns to FIG. (14) Since the length of the blanket 207 is known, if the absolute stop position of the table is not within a predetermined fixed narrow area at this time, the blanket is excessively long or short. If it is within the above range, the tension applying step is normally terminated.

Next, the winding step will be described. In the present invention, the servomotor 2 for driving the blanket cylinder 208 is used.
06 and the servomotor 201 for driving the table 202
Is a master-slave relationship, but either may be the master. In this example, the servo motor 206 is mainly used for convenience. Motor 2
01 finely adjusts the tension accordingly.

The outline of the blanket winding operation is as follows. (1) Both servomotors 206 and 201 are position-controlled, and at the time of simultaneous movement, regardless of the amount of movement of the motor shaft, start and stop are at the same time, ie, two-axis linear interpolation.
Although there is a possibility that one of the servo motors performs torque control, this embodiment will be described in a second embodiment. (2) Winding is performed gradually at a predetermined pitch. Here, the winding pitch amount (relative movement amount) from the winding start position to the winding end position was large at the start and small before the end, and the pitch amount during that period was changed linearly. First, the blanket 207 is wound up by the servo motor 206 by the first pitch, and the servo motor 201 sends it out. The winding and feeding are linearly interpolated. (3) Next, the main servo motor 206 is stopped, and the sub servo motor 201 is slightly moved back and forth on the Y axis so that the winding tension falls within the desired accuracy. (4) If the linear interpolation and the minute correction are repeated for each pitch and sequentially wound, the winding tension is assured as a result.

The reason why the pitch is wide near the winding start position and becomes narrower toward the winding end position is that if the entire length is narrow, the tact becomes longer, and the winding amount of the blanket cylinder 208 is within the pitch.
If the feed rate is too large, the blanket will have a large margin near the winding start position, and the blanket can be expected to grow slightly, even in the micron order, and this can not be expected near the winding end position. This is a safety measure to avoid. For the same reason, the winding speed is high near the winding start position and is gradually reduced toward the winding end position.

Next, an actual winding operation example will be described with reference to the flowchart of the winding main operation example of FIG. The numerical values are examples. (1) The number of blanket divisions (the number of pitches) N, the winding start speed Vs, and the tension correction pitch P of the slave shaft
2 and the tension correction speed V2 of the slave shaft are set. (2) The current pitch Pn that changes according to the remaining winding amount and the moving speed Vn thereof are obtained. Here, a calculation example will be specifically described.

The total distance of the winding blanket (FIG. 1D)
D) = 820 mm and the number of pitch divisions N = 40. Assuming that a pitch reduction amount that is equally reduced every pitch from the winding start pitch Ps is Pd, and an n-th winding pitch amount in the pitch division number N is Pn.

[0050]

(Equation 1) The winding speed Vn at the n-th pitch is calculated by the same method. Winding start speed Vs = 30 mm /
s.

[0051]

(Equation 2) (3) Based on the above result, the table 202 and the blanket cylinder 208 are linearly interpolated and moved at the speed Vn with the table moving amount = Pn and the blanket peripheral rotation amount = Pn, and the blanket 207 is wound by Pn. (4) Wait for the movement of the servo motors 206 and 201 to be completed. (5) The average value Ta of the tension detectors 405 and 401 is obtained. (6) The degree of tension imbalance is checked, and if it exceeds a preset allowable value, the process ends abnormally. (7) The average value Ta is compared with the target tension value Tb, and if the average value Ta is within a preset allowable value, the winding of the pitch ends. If the value is outside the allowable range, a correction operation based on the master-slave relationship shown in FIG. 9 is performed. The description has been given in the section of the tension applying step, and thus the description is omitted here. (8) If the current position of the blanket cylinder 208 has not reached the winding completion position, the process returns to step (2) for calculating the “current moving pitch Pn and its moving speed Vn”, and repeats the operation. During this time, the state is as shown in FIG. When the current position of the blanket cylinder 208 is equal to or exceeds the winding completion position, the winding is completed, the blanket 207 is fixed to the blanket fixing portion 104 of the blanket cylinder 208, the blanket locking portion 102 is removed, and the blanket 207 is mounted. Complete.

Embodiment 2 In Embodiment 1 described above, the position of the slave shaft is controlled. However, by controlling the current of the slave shaft, the blanket 207 can be continuously wound. That is, from the position of FIG.
Until the position (d), the blanket cylinder 208, which is the main shaft, is continuously operated by position control without stopping. During this time, the table 202, which is the slave axis, has the tension detectors 405, 4
The average value Ta of 01 is fed back to perform torque control such that the target tension Tb is realized.

As a matter of course, the relationship between the master and the slave can be reversed, and the process relating to the abnormality monitoring conforms to the first embodiment.

[0054]

According to the offset printing apparatus and the blanket mounting method of the present invention, since the tension applied to the blanket can be controlled almost completely over the entire winding surface of the blanket cylinder, a uniform thickness of the blanket is realized, It greatly contributes to increasing the area of printing.

The safety of the large-size offset printing machine was improved by detecting the application of abnormal tension to the blanket and interrupting the mounting operation.

Further, in the first embodiment, any NC that has a commercially available position control interpolation function can be used.
High versatility.

[Brief description of the drawings]

FIG. 1 is a partial sectional view of a blanket winding process.

FIG. 2 is a schematic basic configuration diagram of an offset printing apparatus.

FIG. 3 is a diagram illustrating the principle of image formation by offset printing.

FIG. 4 is a vector conceptual diagram of an upper surface of blanket tension application by two-point pull according to the present invention.

FIG. 5 is a vector conceptual diagram of the upper surface of blanket tension application by one-point pull according to the related art.

FIG. 6 is a main flowchart of the blanket mounting method of the present invention.

FIG. 7 is a detailed flowchart of an “initial tension application” step in FIG. 6;

FIG. 8 is a detailed flowchart of a [wrapping] step in FIG. 6;

FIG. 9 is a detailed flowchart of a [tension minute correction routine] in FIGS.

FIG. 10 is an electric control configuration according to the present invention.

FIG. FIG. 2 is a top view showing a surface conduction electron-emitting device using a heart well.

FIG. 12 is a top view showing a surface conduction electron-emitting device according to the present applicant.

[Explanation of symbols]

101: A member that locks the load cell on the table side and transmits pressure to the pressure detector, 102: Locking portion, 103: First fixing portion, 104: Second fixing portion, 201: Servo motor for driving the table 202, 202: Table, 203: printing plate, 204: X-direction positioning portion of printing plate or printing medium, 205: Y-direction positioning portion, 206: servo motor for driving blanket cylinder 208, 207: blanket, 208: blanket, 209: doctor, 21
0: Stand, 211: Revolving axis of blanket cylinder, 212:
Doctor's swivel axis, 213: Printed object, 214: Inking mechanism, 215: Ink, 401, 405: Tension detector, 402: Mechanical fulcrum of tension generation on the blanket cylinder side, 40
3,502: vector at the right end when the blanket 207 is pulled by the table, 404, 503: vector at the left end when the blanket 207 is pulled by the table, 5
01: vector at the time of pulling the blanket 207 by the table, 1101: substrate, 1104: conductive thin film, 1
105: electron emitting portion, 1201: insulating substrate, 120
2,1203: Electrode.

Claims (12)

[Claims] 1. A method of mounting a blanket on a blanket cylinder in an offset printing apparatus in which a plate and a workpiece are brought into contact with a blanket mounted on the outer peripheral surface of a rotating blanket cylinder by sliding movement of a table on which the plate and the workpiece are mounted. A first fixing step of fixing one end of the blanket to a first fixing part of the blanket cylinder, a locking step of locking the other end of the blanket to a locking part of the table, and a state in which the blanket cylinder is fixed. The table is moved away from the blanket cylinder by extending the blanket from its natural length to a length to which a predetermined tension is applied. During this time, the amount of movement of the table based on the output signal while monitoring the tension applied to the blanket is monitored. Tensioning process, rotating the blanket cylinder and The blanket is wrapped around the blanket cylinder by moving the bull close to the blanket cylinder, and while the tension applied to the blanket cylinder is monitored, the rotation of the blanket cylinder and the rotation of the blanket cylinder are performed based on the output signal while maintaining the predetermined tension. A winding step of controlling the movement of the table in a master-slave relationship, and a second fixing step of fixing the vicinity of the other end of the blanket to the second fixing portion of the blanket cylinder while maintaining the predetermined tension. How to attach a blanket. 2. The method according to claim 1, wherein the monitoring of the tension in the tension applying step or the winding step is performed at a plurality of locations on the blanket, and the locations are at least one location on both sides of the center line in the winding direction of the blanket. The blanket mounting method according to claim 1, wherein 3. The blanket mounting method according to claim 2, wherein an average value of the detection values of the monitors at the plurality of locations is defined as a tension applied to the blanket. 4. The tension applying step or the winding step is interrupted when the mutual difference between the detection values by the monitor at the plurality of locations exceeds a preset allowable range, and the tension applying step or the winding step is interrupted. 3. The blanket mounting method according to 3. 5. The tension applying step, wherein the total length of the blanket is automatically recognized, and when the recognized numerical value exceeds a preset allowable range, the step is regarded as abnormal and the step is interrupted. 5. The blanket mounting method according to any one of items 1 to 4. 6. The method according to claim 1, wherein in the tension applying step or the winding step, when the process time exceeds a predetermined allowable range, the process is regarded as abnormal and the process is interrupted. Blanket mounting method. 7. The blanket mounting method according to claim 1, further comprising a step of releasing the other end of the blanket from the locking portion of the table after the second fixing step. 8. A contact sliding of a plate and a workpiece with respect to a blanket mounted on an outer peripheral surface of a rotating blanket cylinder,
An offset printing apparatus which is performed by moving a table on which a plate and a work are mounted, wherein a blanket cylinder is provided with a first fixing portion for fixing one end of the blanket during a blanket mounting operation to the cylinder and after the mounting, and a blanket mounting. After the completion, a second fixing portion for fixing the other end of the blanket, the table has a locking portion for temporarily fixing the other end of the blanket at the time of blanket mounting work on the blanket cylinder, Further, a first servomotor for rotating the blanket cylinder, a second servomotor for moving the table in a direction perpendicular to the axis of the blanket cylinder, a tension sensor for monitoring the tension applied to the blanket during blanket mounting work, and a tension sensor Based on the output signal, The first servomotor and the second servomotor are provided with control means for instructing the rotation amount of the cut cylinder and the movement amount of the table to the first servomotor and the second servomotor. The operation of the first servomotor and the second servomotor is performed during blanket mounting work. An offset printing apparatus having a master-slave relationship so that a tension applied to a blanket has a predetermined value. 9. The offset printing apparatus according to claim 8, wherein at least one tension sensor is provided on each of both sides of the center line of the blanket in the winding direction. 10. The offset printing apparatus according to claim 9, wherein an average value of the detection values of the plurality of tension sensors is used as a tension applied to a blanket. 11. The blanket mounting operation is interrupted when the difference between the detected values of the plurality of tension sensors exceeds a preset allowable range, which is regarded as abnormal. Offset printing equipment. 12. An image forming apparatus manufactured by the offset printing apparatus according to claim 8.