JP4084682B2 - Rotating drum rotation control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a rotating drum rotation control device that controls a rotating operation of a rotating drum.
[0002]
[Prior art]
A sheet-shaped recording material, particularly a printing plate having a photosensitive layer on a support, is used, and the axis of the rotating drum is rotated while the printing plate is wound around the peripheral surface of the rotating drum (main scanning). A technique for recording an image with a laser beam or the like directly on the photosensitive layer (emulsion surface) of the printing plate by moving the recording head in the direction (sub-scanning) has been developed (printing plate exposure apparatus). With such a technique, it is possible to quickly record an image on a printing plate (see Patent Document 1). In addition to the printing plate that is generally used after being image-recorded in advance and wound around a printing drum, the printing plate is a printing material that directly records an image on a rotating drum (a long photosensitive film that is sequentially wound around the rotating drum). In addition, the concept of a photosensitive film layer that is repeatedly applied and removed, an engraved plate, and the like is also included.
[0003]
In this type of image recording apparatus, the end portions of the printing plate in the winding direction are held by the front end chuck and the rear end chuck, respectively, but the position of the rear end chuck varies depending on the length of the printing plate in the winding direction. For this reason, the relative position of the rotating drum and the trailing edge chuck is set based on the size information of the printing plate obtained in advance.
[0004]
After the image recording is completed, when the rotation of the rotating drum is stopped, the rear end chuck holding the printing plate is released first, the rotating drum is rotated in the reverse direction, and the printing plate wound around the circumferential surface is removed. The paper is sequentially sent to the discharge tray, the tip chuck is released, and the paper is discharged out of the image recording apparatus.
[0005]
The stop control of the rotary drum after the end of the image is such that the rear end of the printing plate wound around the rotary drum comes to the rear end chuck release position near the discharge tray.
[0006]
For this reason, a sensor for detecting the rotational position of the rotary drum is provided, and the rotational movement amount (number of pulses) after the stop instruction is calculated from the rotational position information by this sensor and the trailing edge position information of the printing plate, The rotating drum is stopped based on the calculation result.
[0007]
[Patent Document 1]
Japanese Patent No. 3179680
[0008]
[Problems to be solved by the invention]
However, in the conventional rotary drum rotation control device, the rotary drum is rotating even while the calculation is being performed. Therefore, the stop position is shifted by the time required for the calculation and the stop is accurately stopped at the rear end chuck release position. I couldn't.
[0009]
For this reason, it is necessary to correct the stop position while the rotational speed of the rotating drum is being reduced or after the rotating drum is stopped, resulting in complicated control of the rotating drum.
[0010]
An object of the present invention is to obtain a rotating drum rotation control device that takes the above fact into consideration and stops the rotating drum rotating at a predetermined position accurately and quickly.
[0011]
[Means for Solving the Problems]
The invention according to claim 1 is a rotating drum rotation control device for controlling the rotating operation of the rotating drum, wherein the rotating position detecting means detects at least one rotating unit of the rotating drum, and the rotation of the rotating drum is stopped. A stop control pulse generating means for detecting a first rotation position of the rotary drum after the input of a stop signal for instructing and calculating and generating a stop control pulse based on the first rotation position; and a stop control pulse generation A second rotation position of the subsequent rotating drum is detected, a correction means for correcting the stop control pulse from a position deviation from the first rotation position detected at the start of stop control pulse generation, and a correction stop corrected by the correction means Control means for controlling the stop of the drum based on the control pulse.
[0012]
The invention according to claim 2 is used in an image recording apparatus that rotates a rotating drum in a state in which a sheet-like recording material is wound around a peripheral surface of the rotating drum, and records an image on the sheet-like recording material, A rotating drum rotation control device for controlling the rotating operation of the rotating drum, the rotating position detecting means for detecting the rotating position in at least one rotation unit of the rotating drum, and a stop signal for instructing the rotation stop of the rotating drum A stop control pulse generating means for detecting a first rotation position of the rotating drum and calculating and generating a stop control pulse based on the first rotation position; and a second of the rotating drum after the generation of the stop control pulse. The correction position for detecting the rotation position of the motor and correcting the stop control pulse from the position deviation from the first rotation position detected at the start of the generation of the stop control pulse, and the correction stop control corrected by the correction means Based on the pulse has a control means for controlling the stopping of the drum, the.
[0013]
According to a third aspect of the present invention, there is provided an image recording method in which an image is recorded by moving a recording head in an axial direction of the rotating drum with respect to a rotating rotating drum in a state where a sheet-like recording material is wound around a peripheral surface A rotary drum rotation control device that is used in an apparatus and controls a rotation operation of the rotary drum, wherein the rotary position detection means detects a rotational position in units of at least one rotation of the rotary drum, and instructs to stop the rotation of the rotary drum. After the stop signal is input, stop control pulse generating means for detecting the first rotation position of the rotary drum and calculating and generating a stop control pulse based on the first rotation position, and the stop control pulse after the generation A second rotating position of the rotating drum is detected, and correction means for correcting the stop control pulse from the position deviation from the first rotating position detected at the start of generation of the stop control pulse is corrected by the correcting means. Based on the correction stop control pulse has a control means for controlling the stopping of the drum, the.
[0014]
According to the first to third aspects of the invention, since the rotational position detecting means detects the rotational position at least in one rotation unit of the rotating drum, the rotational position of the rotating drum at the time of detection can be grasped. The first rotation position for detecting the first rotation position of the rotating drum after inputting the stop signal instructing the rotation stop of the rotating drum and stopping the rotating drum at the predetermined stop position by the stop control pulse generating means. A stop control pulse based on the above is calculated and generated, and the rotating drum is surely stopped at a predetermined stop position. Further, the second rotation position for executing the stop process is detected, the correction means corrects the stop control pulse from the positional deviation between the first rotation position and the second rotation position, and the control means based on the corrected stop control pulse. Thus, the stop of the rotating drum is controlled so that the stop position is not displaced by the time required for calculating and generating the stop control pulse.
[0015]
Therefore, in particular, the rotating drum that rotates at high speed can be stopped at a predetermined position accurately and quickly.
[0016]
The invention according to claim 4 is the invention according to any one of claims 1 to 3, The rotational position detecting means outputs one pulse every time the rotating drum makes one rotation, and the correcting means is a position deviation canceling process by replacing the first rotational position with the second rotational position. The calculation and generation of the stop control pulse is started when the relatively first rotation position is detected, and the rotation drum is stopped when the relatively second rotation position is detected. Start It is characterized by that.
[0017]
According to a fourth aspect of the present invention, the rotational position detecting means according to the first to third aspects is adapted to output one pulse during one rotation of the rotating drum, and the rotational position is determined in units of one rotation. Detected by To do. The correction means is a position deviation canceling process by replacing the first rotational position with the second rotational position, and calculates and generates a stop control pulse when detecting the first rotational position that is relatively preceding. Start and start the rotary drum stop control when detecting the second rotational position which is relatively later Therefore, there is no need to consider the rotation angle difference , Times It is possible to stop the rotating drum at a predetermined position accurately and quickly.
[0018]
According to a fifth aspect of the present invention, in the invention according to any one of the first to fourth aspects, the control means rotates after the stop signal is input and before the calculation of the stop control pulse generating means is started. Deceleration of the rotational speed of the drum is started, and when the stop control pulse can be calculated and generated during one rotation of the rotating drum, the deceleration is stopped and the first rotation position is detected. .
[0019]
According to the fifth aspect of the present invention, the control means according to any one of the first to fourth aspects determines the rotational speed of the rotary drum after the stop signal is input and before the stop control pulse generating means starts calculation. The rotation position detecting means detects the first rotation position after decelerating to a rotation speed at which a stop control pulse can be calculated and generated during one rotation, and immediately after the stop signal is input, Since the rotation speed is reduced, the time from the stop signal input to the rotation stop is shortened.
[0020]
The invention according to claim 6 is the invention according to any one of claims 1 to 3, wherein the rotational position detecting means outputs a plurality of pulses while the rotating drum makes one rotation, and the stop After the signal is input, the first rotation position is detected and the calculation and generation of the stop control pulse by the stop control pulse generating means is started. After the stop control pulse is generated, the second rotation position is detected and the first detection position is determined. It is characterized in that the stop control pulse is corrected by the correcting means by the rotation angle difference from the second detection position.
[0021]
According to the sixth aspect of the present invention, the rotational position detecting means of the first to third aspects outputs a plurality of pulses during one rotation of the rotating drum, and the rotational position of the rotating drum is determined. Since the rotation can be detected a plurality of times, the rotation position can be detected immediately regardless of the rotation position of the rotating drum. Further, after the stop signal is input, the first rotation position is detected, and the calculation and generation of the stop control pulse by the stop control pulse generating means is started. After the stop control pulse is generated, the second rotation position is detected and corrected. As a result, the stop control pulse is corrected by the rotation angle difference between the first detection position and the second detection position, so that the stop position can be promptly controlled without shifting the stop position for the time required for calculation and generation of the stop control pulse. Pulse correction can be performed.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment)
FIG. 1 shows an exposure unit 14 of the printing plate automatic exposure apparatus according to the present embodiment.
[0023]
The exposure unit 14 includes a rotating drum 16 that winds and holds the printing plate 12 around the peripheral surface, and the printing plate 12 is guided by a conveyance guide unit 18 and is tangential to the rotating drum 16. It comes to be sent from.
[0024]
A puncher 24 that forms a notch for positioning at the front end of the printing plate 12 is disposed at the top of the rotary drum 16 in FIG.
[0025]
The conveyance guide unit 18 includes a plate supply guide 20 and a plate discharge guide 22, and the plate feed guide 20 and the plate discharge guide 22 of the conveyance guide unit 18 are in a horizontal V-shape with respect to each other. As a center on the right end side in FIG. By this rotation, the plate supply guide 20 and the plate discharge guide 22 can be selectively made to correspond to the rotating drum 16 or the puncher 24.
[0026]
After forming a notch for positioning on the printing plate 12 with the puncher 24, the printing plate 12 is once returned to the plate feeding guide 20, and the conveyance guide unit 18 is rotated to correspond to the rotating drum 16.
[0027]
The rotating drum 16 is driven by a driving means (not shown) in the mounting exposure direction of the printing plate 12 (in the direction of arrow A in FIG. 1) and in the removal direction of the printing plate 12 opposite to the mounting exposure direction (in the direction of arrow B in FIG. 1). It is rotated.
[0028]
A tip chuck 26 is attached to the rotary drum 16 provided in the exposure unit 14 at a predetermined position on the outer peripheral surface. In the exposure unit 14, when the printing plate 12 is mounted on the rotating drum 16, first, the front end chuck 26 is opposed to the front end of the printing plate 12 fed by the plate supply guide 20 of the conveyance guide unit 18 (printing plate). The rotating drum 16 is stopped at the mounting position).
[0029]
The exposure unit 22 is provided with a mounting unit 28 facing the front end chuck 26 at the printing plate mounting position. The front end chuck 26 allows the printing plate 12 to be inserted between the front end chuck 26 and the peripheral surface of the rotary drum 16 when the telescopic rod 28A of the mounting unit 28 extends and is pressed on one end side.
[0030]
In the exposure unit 14, in a state where the front end of the printing plate 12 is inserted between the front end chuck 26 and the rotary drum 16, the expansion rod 28 </ b> A of the mounting unit 28 is pulled back to release the pressure on the front end chuck 26, thereby printing. The front end of the plate 12 is sandwiched and held between the front end chuck 26 and the peripheral surface of the rotary drum 16.
[0031]
At this time, the printing plate 12 is positioned by being abutted against a positioning pin (not shown) provided on the rotary drum 16.
[0032]
In the exposure unit 14, when the leading end of the printing plate 12 is fixed to the rotary drum 16, the rotary drum 16 is rotated in the mounting exposure direction. Thereby, the printing plate 12 fed from the plate supply guide 20 of the conveyance guide unit 18 is wound around the circumferential surface of the rotary drum 16.
[0033]
A squeeze roller 30 is disposed in the vicinity of the peripheral surface of the rotary drum 16 on the downstream side in the mounting exposure direction from the printing plate mounting position. The squeeze roller 30 moves toward the rotating drum 16 to press the printing plate 12 wound around the rotating drum 16 toward the rotating drum 16, thereby bringing the printing plate 12 into close contact with the peripheral surface of the rotating drum 16.
[0034]
Further, a rear end chuck attaching / detaching unit 32 is disposed in the exposure unit 14 upstream of the squeeze roller 30 in the mounting exposure direction of the rotary drum 16 (further upstream than the front end chuck 26). In the rear end chuck attaching / detaching unit 32, a rear end chuck 36 is attached to the front end of the shaft 34 protruding toward the rotary drum 16.
[0035]
In the exposure unit 14, when the rear end of the printing plate 12 wound around the rotary drum 16 faces the rear end chuck attaching / detaching unit 32, the shaft 34 is protruded and the rear end chuck 36 is mounted at a predetermined position on the rotary drum 16. . Thereby, the rear end of the printing plate which is different for each printing plate can be sandwiched and held between the rear end chuck 36 and the rotary drum 16.
[0036]
In the exposure unit 14, the squeeze roller 30 is separated when the front end and the rear end of the printing plate 12 are held by the rotary drum 16.
[0037]
FIG. 2 shows a control system for rotation of the rotary drum 16, movement of the recording head 37, and image recording by the recording head 37 based on the image signal.
[0038]
The controller 50 that controls the entire apparatus includes an image processing system control unit 52 that controls image processing and transmission of image data, and a drive system control unit 54 that controls the operation of each unit.
[0039]
The rotating drum 16 is rotated by the driving force of the servo motor 64, and the rotation speed of the servo motor 64 is controlled based on the driving pulse from the rotating drum drive control unit 58 of the drive system control unit 54. .
[0040]
A rotary encoder 44 that is coaxial with the rotary drum 16 is provided at the shaft portion at one axial end of the rotary drum 16 so as to generate a pulse signal corresponding to the rotational speed of the rotary drum 16. .
[0041]
This pulse signal is a basic pulse at the timing of sending image data when the image processing system controller 52 scans and exposes an image with the recording head 37.
[0042]
Further, the rotary encoder 44 is marked with an arbitrary position which is a circumferential reference from the axis of the rotary drum 16 and serves as a reference for rotation, and is set as the rotation reference position 40, and a rotation position for detecting the rotation reference position 40. A sensor 42 is provided so as to face the rotating drum 16, and the rotation reference position 40 is detected every time the rotating drum 16 makes one rotation.
[0043]
The recording head 37 is supported by a support shaft 38 and emits light input from each light source of a light source unit 48 provided with a plurality of light sources (LD, etc.) as a light beam. It moves on the support shaft 38 in the axial direction of the rotary drum 16 by the driving force.
[0044]
Here, the recording head drive unit 60 that drives the motor 62 controls the rotational speed of the motor 62 so that the recording head 37 moves on the support shaft 38 in accordance with the rotational speed of the rotary drum 16.
[0045]
As a result, the recording head body 37 moves (sub-scans) along the support shaft 38 in accordance with the rotation (main scanning) of the rotary drum 16, so that the image based on the image data is scanned and exposed on the printing plate 12. The
[0046]
In the exposure unit 14, when the scanning exposure to the printing plate 12 is completed, the rear end chuck 36 holding the rear end of the printing plate 12 is at a position facing the rear end chuck attaching / detaching unit 32 (rear end chuck attaching / detaching position). The rotary drum 16 is stopped, and the rear end chuck 36 is removed from the rotary drum 16. Thereby, the rear end of the printing plate 12 is opened.
[0047]
In the present embodiment, since the rear end chuck attaching / detaching position varies depending on the winding direction length of the printing plate 12 wound around the rotating drum 16, in order to reliably stop the rotating drum 16 at the rear end chuck attaching / detaching position, A stop position calculation processing unit 56 for calculating the stop position of the rotary drum 16 is provided.
[0048]
As shown in FIG. 3, the stop position calculation processing unit 56 includes a rotation position pulse capturing unit 72 that captures the rotation position of the rotation position sensor 42, a calculation unit 74 that calculates and generates a stop control pulse, and a stop operation. And a stop operation starting unit 76 for instructing the start.
[0049]
In the stop position calculation processing unit 56, when the stop instruction signal 70 is input, the rotational position pulse capturing unit 72 captures the rotational position detection pulse from the rotational position sensor 42.
[0050]
The calculation unit 74 obtains the position of the rear end chuck 36 from the printing plate size information using the stop instruction signal and the rotation position pulse as a trigger, and stops the rotary drum 16 at the rear end chuck attaching / detaching position based on the rotation reference position 40. The calculation of the stop control pulse is started, and the calculated stop control pulse is temporarily stored in the rotary drum driving unit 58.
[0051]
After the calculation of the stop control pulse is completed, the rotation position detection pulse from the rotation position sensor 42 is taken into the stop operation starting unit 76, and the stop operation starting unit 76 is configured so that the rotation reference position 40 is set by the rotation position sensor 42. When detected, it serves to send a stop operation start signal for starting the stop operation to the rotary drum drive unit 58.
[0052]
The operation of the present embodiment will be described below.
[0053]
First, the rotary drum 16 is stopped so that the front end chuck 26 comes to the printing plate mounting position, the printing plate 12 is opposed to the puncher 24 by the plate feeding guide 20, and a positioning notch is formed at the front end of the printing plate 12. The printing plate 12 is once returned to the plate supply guide 20.
[0054]
The printing plate 12 is transported from the tangential direction of the rotary drum 16 to the peripheral surface of the rotary drum 16 by the plate feed guide 20, positioned by bringing the positioning notch of the printing plate 12 into contact with the positioning pin, and rotated with the tip chuck 26. The front end of the printing plate 12 is sandwiched and held by the peripheral surface of the drum 16.
[0055]
The rotary drum 16 is rotated to wind the printing plate 12 around the peripheral surface. When the rear end of the printing plate 12 faces the rear end chuck 36, the printing plate 12 is sandwiched and held by the rear end chuck 36 for exposure. Preparation is complete.
[0056]
Next, image data is read, and an exposure process is started by a light beam from the recording head unit 37. The exposure process is so-called scanning exposure in which the recording head unit 37 is moved in the axial direction of the rotating drum 16 while rotating the rotating drum 16 at high speed (main scanning).
[0057]
When the exposure process is completed, the controller 50 performs a rotation stop process. Hereinafter, the rotation stop process executed by the controller 50 will be described with reference to the time chart of FIG.
[0058]
In FIG. 4, “rotational position sensor” indicates the state of the detection pulse of the rotational position sensor 42. The detection pulse is “1” when the rotation reference position 40 is detected, and when it is not detected. “0”. “Exposure processing” indicates that exposure processing is in progress (“ON”) or non-exposure processing (“OFF”). “Stop instruction signal” is “ON” for stop instruction signal input, “No” for stop instruction signal input. “OFF”, and “arithmetic processing” indicates that arithmetic processing is in progress (“ON”) or non-arithmetic processing “OFF”. Further, the rotation speed (v) indicates a rotation speed based on the rotation speed information from the rotary encoder 44.
[0059]
When the exposure process is completed, the controller 50 inputs a rotation stop instruction signal to the stop position calculation processing unit 56, takes in the detection pulse of the rotation reference position 40 from the rotation position sensor 42 in the rotation position pulse capturing unit 72, and The position of the rear end chuck 36 is obtained from the printing plate size information, and at the same time when the position rotation reference position 40 is detected (see A in FIG. 4), the rotation drum 16 is rotated by the calculation unit 74 and the rotation position sensor 42 is set to the rotation reference position 40 A stop control pulse is calculated so that the rear end chuck 36 is stopped at the rear end chuck attaching / detaching position facing the rear end chuck attaching / detaching unit 32 at the shortest time from the detection.
[0060]
When the calculation is completed (see B in FIG. 4), the stop control pulse is temporarily stored in the rotary drum drive unit 58 and the stop operation starting unit 76 takes in the detection pulse of the rotation reference position 40 from the rotation position sensor 42.
[0061]
At the timing when the rotational position sensor 42 detects the rotation reference position 40 (see C in FIG. 4), a stop operation start signal is input to the rotary drum drive unit 58 so as to start the stop operation.
[0062]
The rotating drum drive unit 58 drives the servo motor 64 according to the calculated stop control pulse, and stops the rotation of the rotating drum 16.
[0063]
When the rotation of the rotating drum 16 stops, the trailing end chuck 36 is released by the trailing end chuck attaching / detaching unit 32, the conveyance guide unit 18 is switched (the discharge guide 22 is made to correspond to the rotating drum 16), and then the rotating drum 16 is printed. The printing plate 12 is rotated in the direction in which the plate 12 is taken out, and the printing plate 12 wound around the rotary drum 16 is discharged in the tangential direction from the rear end side. At this time, the printing plate 12 is sent to the discharge plate guide 22.
[0064]
As described above, according to the printing plate automatic exposure apparatus of the first embodiment, the rotation position detection sensor 42 detects the rotation reference position 40 for each rotation of the rotary drum 16, so that the rotation at the time of detection is performed. The rotational position of the drum 16 can be grasped. The rotation reference position 40 of the rotary drum 16 is detected after the rotation stop instruction signal 70 of the rotary drum 16 is input, and the stop position calculation processing unit 56 stops the rotary drum 16 from the rotation position at the rear end chuck attaching / detaching position. A stop control pulse is calculated to reliably stop the rotary drum 16 at the rear end chuck attaching / detaching position. Further, when the rotation reference position 40 is detected after the calculation is completed, the stop process is executed by the rotary drum driving unit 58 so that the stop position is not shifted by the time required for the calculation and generation of the stop control pulse. I have to.
[0065]
Therefore, it is possible to stop the rotating drum that rotates at a high speed accurately and quickly at a predetermined position.
[0066]
(Second Embodiment)
In the first embodiment, the stop position calculation processing unit 56 calculates the stop position of the rotary drum 16 after the exposure is completed, and stops according to the calculation result. However, in the second embodiment, the exposure is performed. A description will be given of an example in which the rotational speed of the rotary drum 16 is decelerated to a predetermined rotational speed after the processing is completed, and then the stop position is calculated by the stop position calculation processing unit 56 and stopped according to the calculation result.
[0067]
Since the configuration of the printing plate automatic exposure apparatus in this embodiment is the same as that of the exposure unit 14 shown in the first embodiment, the same reference numerals are given here and description thereof is omitted.
[0068]
When the exposure process by the image processing system control unit 52 is completed, the controller 50 performs a rotation stop process. Hereinafter, the rotation stop process executed by the controller 50 will be described with reference to the time chart of FIG.
[0069]
In FIG. 5, “rotational position sensor” indicates the state of the detection pulse of the rotational position sensor 42. The detection pulse is “1” when the rotation reference position 40 is detected, and is not detected. The time is “0”. “Exposure processing” indicates that exposure processing is in progress (“ON”) or non-exposure processing (“OFF”). “Stop instruction signal” is “ON” for stop instruction signal input, “No” for stop instruction signal input. “OFF”, and “arithmetic processing” indicates that arithmetic processing is in progress (“ON”) or non-arithmetic processing “OFF”. Further, the rotation speed (v) indicates a rotation speed based on the rotation speed information from the rotary encoder 44.
[0070]
When the exposure process is completed, the controller 50 inputs a stop instruction signal to the stop position calculation processing unit 56 (see D in FIG. 5). The stop position calculation processing unit 56 generates a control pulse for reducing the rotation speed of the rotary drum 16, and the rotary drum driving unit 58 reduces the rotation speed of the rotary drum 16 to a predetermined speed via the servo motor 64.
[0071]
Here, the interval at which the rotation position sensor 42 detects the rotation reference position 40, that is, the time required for one rotation of the rotary drum 16 is t1, and the time required for the calculation of the stop control pulse by the stop position calculation processing unit 56 is t. Then, the relationship between t and t1 during the exposure process is t> t1.
[0072]
When the rotational speed of the rotary drum 16 is decelerated and the time required for one rotation is increased along with the reduction of the rotational speed and t <t1, the rotational position pulse capturing section 72 detects the rotational reference position 40 detection pulse. (Refer to E of FIG. 5), the rotation speed of the rotary drum 16 is stopped and the rotation speed is maintained at a constant speed, and the rotation reference position 40 is detected by the calculation unit 74, and the trailing edge is determined from the printing plate size information. The position of the chuck 36 is obtained, and a stop control pulse for stopping the rotary drum 16 at the rear end chuck attaching / detaching position is calculated.
[0073]
When the calculation is finished in the calculation unit 74, the stop control pulse is temporarily stored in the rotary drum drive unit 58, and the detection pulse of the rotation reference position 40 of the rotation position sensor 42 is taken in by the stop operation starting unit 76, and the rotation reference position 40 is set. When detected (see F in FIG. 5), a stop operation start signal is input to the rotary drum drive unit 58, and an instruction is given to start the stop operation according to the calculation result.
[0074]
The rotating drum driving unit 58 drives the servo motor 64 based on the stop control pulse, and stops the rotating drum 16 at the rear end chuck attaching / detaching position.
[0075]
As described above, in the drive system control unit 54 of the second embodiment, the rotation speed of the rotary drum 16 is input after the stop signal is input to the stop position calculation processing unit 56 and before the calculation in the calculation unit 74 is started. Is reduced to a rotation speed at which the calculation of the stop control pulse in the calculation unit 74 is completed while the rotary drum 16 makes one rotation, and the calculation unit 74 stops at the same time when the rotation reference position 40 of the next rotation position sensor 42 is detected. The rotation pulse 16 is stopped by calculating the control pulse, and the rotation speed of the rotation drum 16 is immediately reduced after the stop signal is input, so the time required for the stop process is shortened.
[0076]
In the first and second embodiments, a mark is provided as the rotation reference position 40 for acquiring the rotation position of the rotary drum 16 and is detected by the rotation position sensor 42. May be provided and detected by the rotational position sensor 42.
[0077]
In the first and second embodiments, the rotation reference position 40 is detected by the rotation position sensor 42. However, the position information may be grasped by a pulse signal from the rotary encoder 44. In this case, the rotational position sensor 42 may not be provided.
[0078]
When all the signals of the rotary encoder 44 that outputs a plurality of pulses in one rotation are used as they are, for example, as shown in FIG. 6, after the stop instruction signal 70 is input, the rotational position pulse capturing unit 72 uses the rotational position sensor. The rotation position pulse is taken in from 42, and calculation of the stop control pulse is started by the calculation unit 74 when the rotation position is detected. After the calculation is completed, the stop operation start unit 76 takes in the rotation position pulse from the rotation position sensor 42, and when the rotation position is detected, the stop operation start signal is input to the rotary drum drive unit 58. The calculation control unit 74 may correct the stop control pulse by the rotation angle deviation (see Δ in FIG. 6) of the rotary drum 16 at the start of calculation and when the stop operation is started.
[0079]
Furthermore, in the first and second embodiments, the rotation reference position 40 is provided at a position unrelated to the front end chuck 26 and the rear end chuck 36. However, the present invention is not limited to this, for example, the rotation reference position. May be at the same position as the front end chuck 26 or at the same position as the rear end chuck 36. By doing so, the calculation processing of the current position of the rear end chuck 36 is facilitated.
[0080]
In the first embodiment and the second embodiment, the rotary drum stop control has been described by taking the exposure unit 14 of the printing plate automatic exposure apparatus as an example. However, the rotary drum rotation control apparatus of the present invention is a rotary drum. The present invention can also be applied to an apparatus using the. Further, the present invention is not limited to an image recording system rotating drum, and can be applied to rotation control of an ink processing system plate cylinder that winds a printing plate and supplies ink to print on printing paper. Hereinafter, as a third embodiment, in a rotating drum of an image recording system, a photosensitive film is sequentially wound around a plate cylinder instead of a printing plate, and image recording and ink supply are performed together. An example of application to a cylinder) machine is shown. As a fourth embodiment, an example of application to a multicolor printing machine having a function of automatically winding and unwinding a printing plate around a printing cylinder of a printing machine is shown.
[0081]
(Third embodiment)
FIG. 7 shows an outline of a CTC printer 100 according to the third embodiment of the present invention.
[0082]
A large diameter impression cylinder 104 is disposed in the center of the housing 102.
[0083]
The impression cylinder 104 is configured such that sheets are fed one by one from the sheet feeding unit 105 and wound around the circumferential surface. Note that the circumference of the pressure drum 104 is four times or more the length in the sheet conveyance direction, and four sheets can be wound at the same time. The front and rear ends of each sheet in the conveyance direction are chucked by the chuck portion 104A and are in close contact with the peripheral surface of the impression cylinder 104.
[0084]
Around the impression cylinder 104, four sets of printing units 106 are provided. The printing unit 106 has a role of supplying images of colors of Y (yellow), M (magenta), C (cyan), and K (black) to the impression cylinder 104, respectively.
[0085]
The printing unit 106 includes a blanket cylinder 108 that comes into contact with the impression cylinder 104 (contacts paper), and a plate cylinder 110 that transfers an image for each color to the blanket cylinder 108.
[0086]
The plate cylinder 110 moves so as to be able to contact and separate from the blanket cylinder 108.
[0087]
As shown in FIG. 8, the plate cylinder 110 has a hollow structure, and rotary shafts 112 and 114 are attached to two locations eccentric to the rotational axis of the plate cylinder 110 itself. On one rotating shaft 112, an unexposed photosensitive film 116 is wound in layers.
[0088]
The photosensitive film 116 drawn out from the one rotating shaft 112 protrudes from the through-hole 110A that communicates with the inside and outside of the plate cylinder 110, is wound almost once around the peripheral surface of the plate cylinder 110, and again passes through the through-hole 110A. It enters and is wound around the other rotating shaft 114.
[0089]
The rotating shafts 112 and 114 rotate so as to send out the photosensitive film 116 in one-way in units of length wound around the outer periphery of the plate cylinder 110.
[0090]
As shown in FIG. 7, an exposure head 118 is disposed opposite to the peripheral surface of the plate cylinder 110, and an unexposed photosensitive film 116 is wound around the outer periphery of the plate cylinder 110 in accordance with an image signal. At the same time, the plate cylinder 110 is rotated at a high speed (separated from the blanket cylinder 108) to record an image on the photosensitive film 116.
[0091]
After the image recording is completed, the plate cylinder 110 is stopped at a predetermined position and moved to a contact position with the blanket cylinder 108 in synchronization with the conveyance of the paper wound around the impression cylinder 104.
[0092]
The plate cylinder 110 is supplied with ink of each color from an ink tank 122 via a plurality of roller groups 120. Therefore, ink is applied to either the image recording area or the non-image recording area of the photosensitive film 116 wound around the plate cylinder 110 (depending on whether it is negative or positive), and is wound around the impression cylinder 104 via the blanket cylinder 110. Ink is transferred onto the printed paper.
[0093]
The color printing is completed by transferring the images by overlapping the four sets of printing units 106.
[0094]
The paper after color printing is peeled off from the impression cylinder 104 by the belt conveyor 124, conveyed to the paper discharge unit 126 along the belt conveyor 124, and collected.
[0095]
Here, when the print image is changed, the rotating shafts 112 and 114 inside the plate cylinder 110 are rotated to remove the already exposed photosensitive film 116 (winding around the other rotating shaft 114). An unexposed photosensitive film 116 is wound around the outer periphery of the plate cylinder 110 (drawn from one rotating shaft 112). Thereby, the operation | work which attaches and detaches a printing plate to the plate cylinder 110 becomes unnecessary each time, and it can improve printing work efficiency.
[0096]
In the CTC printer 100 configured as described above, when recording an image on the unexposed photosensitive film 116, the plate cylinder 110 is rotated at a high speed, and after image recording, one end (leading edge or trailing edge) of the image is set to a predetermined value. It stops in the state positioned in position, and shifts to the contact process with the blanket cylinder 108.
[0097]
At this time, since the position of the trailing edge of the image differs depending on the image area, it is necessary to calculate the stop position according to the recorded image information. Also, in the positioning of the leading edge, it is necessary to perform calculation processing each time depending on the relative positional relationship with the paper.
[0098]
In this case, a quick stop from high-speed rotation is required, but a control delay due to arithmetic processing causes color misregistration.
[0099]
By applying the present invention to such stop control from high-speed rotation of the plate cylinder 110, quick and highly accurate stop control is possible.
[0100]
(Fourth embodiment)
FIG. 9 shows an outline of a multicolor printing machine 150 according to the fourth embodiment of the present invention.
[0101]
The casing 152 is provided with two upper and lower stages 154 and 156, and paper is normally supplied from the lower stage 156.
[0102]
The supplied paper is fed to the peripheral surface of the lower impression cylinder 160 of the pair of impression cylinders 160 and 162 rotating at the same linear speed with the transfer cylinder 158 as the center.
[0103]
The sheet enters the peripheral surface of the lower impression cylinder 160 from the tangential direction, and is sandwiched between the delivery cylinder 164 so that the sheet is wound around the lower impression cylinder 160 and is about half a circumference. .
[0104]
When the half circumference is completed, the sheet is conveyed to the upper impression cylinder 162 via the transfer cylinder 158.
[0105]
The sheet enters from the tangential direction of the upper impression cylinder 162, is sandwiched by the transfer cylinder 158, is wound around the upper impression cylinder 162, and makes a half turn.
[0106]
When the half cycle is completed, the sheet is discharged from the upper stage 154 to the outside of the housing 152.
[0107]
Here, two sets of printing units 166 are arranged to face each other in the half-circumferential region around which the paper is wound in each of the impression cylinders 160 and 162.
[0108]
The printing unit 166 prints an image for each color (YMCK) based on the same image by superimposing on the paper, and the paper moves sequentially while being wound around the plate cylinders 160 and 162. Are overlaid and multicolor printing is applied.
[0109]
In addition, an additional image (for example, special colors, characters, stamps, etc.) different from each color of YMCK is printed on the upper plate cylinder 162, or an uppermost layer of a multicolor image is coated. A printing unit 168 is provided. Since the 4 + 1 (= 5) sets of printing units 166 and 168 including the additional printing unit 168 have the same structure, the structure of one of them (the lowermost printing unit 166 in FIG. 9) will be described and the others will be described. The description of the structure is omitted.
[0110]
The printing unit 166 includes a blanket cylinder 170 that is in contact with the impression cylinder 160, a plate cylinder 172 that is in contact with the blanket cylinder 170, and an ink application device 174. A printing plate 176 is wound around the plate cylinder 172, and ink supplied from the ink coating device 174 is applied to an image area or a non-image area (depending on whether it is negative or positive), and the impression cylinder is transferred via the blanket cylinder 170. In this configuration, the paper is printed on paper that is wound around 160 and conveyed.
[0111]
In the multi-color printing apparatus 150, the plate cylinder 172 around which the printing plate 176 is wound is synchronized with the position of the paper wound around the impression cylinder 160, so that multi-color print images are printed without being displaced. Is done.
[0112]
Here, in order to speed up the printing process, it is necessary to rotate the plate cylinder 172 around which the printing plate 176 is wound at a high speed and to position each of the sequentially fed sheets.
[0113]
By applying the present invention to such stop control from high-speed rotation of the plate cylinder 172, quick and highly accurate stop control becomes possible.
[0114]
Note that the printing plate 176 needs to be replaced when the image changes. At that time, the printing plate 176 can be supplied from the lower stage 156 and automatically wound around the plate cylinder 172. Even in such a replacement operation of the printing plate 176, the present invention can be applied to stop control of the winding leading end position (or rear end position) or the like.
[0115]
In the multicolor printing machine 150, the printing plate 176 is wound around the plate cylinder 172. However, as shown in FIG. 10A, the photosensitive film layer 180 is coated on the peripheral surface of the plate cylinder 172 by a coating spray 178. 10B, an image is formed by the recording head 182 as shown in FIG. 10B, and after the printing of the image is completed, the image is removed by the coating removing device 184 as shown in FIG. After removing the formed film layer, a CTC direct input type plate cylinder 172 may be applied in which a new photosensitive film layer 180 is coated again by the coating spray 182.
[0116]
【The invention's effect】
As described above, according to the present invention, a sheet-like recording material is wound around the circumferential surface of the rotating drum, and the recording head moves in the axial direction of the rotating drum along the circumferential surface of the rotating drum rotating at high speed. In the image recording rotary drum rotation control device that controls the rotation and stop of the rotary drum, the rotary drum that rotates at high speed can be stopped at a predetermined position with high accuracy. Has an effect.
[Brief description of the drawings]
FIG. 1 is a schematic view of an automatic printing plate exposure apparatus according to the present embodiment.
FIG. 2 is a block diagram showing an outline of a controller for driving a rotary drum and a recording head.
FIG. 3 is a block diagram illustrating a configuration of a stop position calculation processing unit.
FIG. 4 is a time chart of rotation stop processing executed by a controller in the first embodiment.
FIG. 5 is a time chart of rotation stop processing executed by a controller in the second embodiment.
FIG. 6 is a time chart showing another embodiment of rotation stop processing.
FIG. 7 is a schematic view of a CTC printer according to a third embodiment.
FIG. 8 is an enlarged view of a plate cylinder of a CTC printing machine according to a third embodiment.
FIG. 9 is a schematic view of a multicolor printing machine according to a fourth embodiment.
FIGS. 10A and 10B are diagrams showing an image recording process for a plate cylinder when a direct input type cylinder is applied, according to a modification of the fourth embodiment, wherein FIG. 10A is a coating process, and FIG. 10B is an exposure process; (C) It is a coating removal process.
[Explanation of symbols]
12 Printing plate (sheet-shaped recording material)
14 Exposure section
16 Rotating drum
32 Rear end chuck attachment / detachment unit
34 Shaft
36 Rear end chuck
37 Recording head
42 rotational position sensor (rotational position detection means)
44 Rotary encoder
50 controller (control means)
54 Drive system controller
56 Stop position calculation processing unit (stop control pulse generating means)
58 Rotary drum drive
64 servo motors

Claims (6)

A rotary drum rotation control device for controlling the rotation operation of the rotary drum,
A rotational position detecting means for detecting a rotational position at least in one rotation unit of the rotating drum;
Stop control pulse generation means for detecting a first rotation position of the rotary drum after the input of a stop signal instructing rotation stop of the rotary drum, and calculating and generating a stop control pulse based on the first rotation position; ,
Correction means for detecting a second rotational position of the rotating drum after generation of the stop control pulse and correcting the stop control pulse from a position deviation from the first rotational position detected at the start of the generation of the stop control pulse;
Control means for controlling the stop of the drum based on the correction stop control pulse corrected by the correction means;
An image recording rotary drum rotation control device. The rotating drum is used in an image recording apparatus that rotates the rotating drum with the sheet-like recording material wound around the circumferential surface of the rotating drum and records an image on the sheet-like recording material, and controls the rotating operation of the rotating drum. A rotary drum rotation control device,
A rotational position detecting means for detecting a rotational position at least in one rotation unit of the rotating drum;
Stop control pulse generation means for detecting a first rotation position of the rotary drum after the input of a stop signal instructing rotation stop of the rotary drum, and calculating and generating a stop control pulse based on the first rotation position; ,
Correction means for detecting a second rotational position of the rotating drum after generation of the stop control pulse and correcting the stop control pulse from a position deviation from the first rotational position detected at the start of the generation of the stop control pulse;
Control means for controlling the stop of the drum based on the correction stop control pulse corrected by the correction means;
A rotary drum rotation control device. The recording head is used in an image recording apparatus for recording an image by moving in the axial direction of the rotating drum with respect to a rotating drum that rotates with a sheet-like recording material wound around the circumferential surface. A rotary drum rotation control device for controlling the rotation operation,
A rotational position detecting means for detecting a rotational position at least in one rotation unit of the rotating drum;
Stop control pulse generation means for detecting a first rotation position of the rotary drum after the input of a stop signal instructing rotation stop of the rotary drum, and calculating and generating a stop control pulse based on the first rotation position; ,
Correction means for detecting a second rotational position of the rotating drum after generation of the stop control pulse and correcting the stop control pulse from a position deviation from the first rotational position detected at the start of the generation of the stop control pulse;
Control means for controlling the stop of the drum based on the correction stop control pulse corrected by the correction means;
A rotary drum rotation control device. The rotation position detection means outputs one pulse every time the rotating drum makes one rotation,
The correction means is a position deviation canceling process by replacing the first rotational position with the second rotational position;
Calculation and generation of the stop control pulse is started when the relatively first rotation position is detected, and stop control of the rotating drum is started when the relatively second rotation position is detected. rotary drum rotation control apparatus according to any one of claims 1 to 3, characterized in that.   The control means starts deceleration of the rotational speed of the rotating drum after the stop signal is input and before the calculation of the stop control pulse generating means, and the stop control pulse is calculated and generated while the rotating drum makes one revolution. The rotary drum rotation control device according to any one of claims 1 to 4, wherein the rotation position is stopped and the first rotation position is detected when it becomes possible.   The rotation position detection means outputs a plurality of pulses while the rotation drum makes one rotation, detects the first rotation position after inputting the stop signal, and calculates and generates a stop control pulse by the stop control pulse generation means. And detecting the second rotation position after generating the stop control pulse, and correcting the stop control pulse by the correction means by the rotation angle difference between the first detection position and the second detection position. Item 4. The rotating drum rotation control device according to any one of Items 3 to 4.

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