JP2820231B2 - Gap control device for gravure engraving machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gravure engraving machine, and more particularly to a gap control device for adjusting a gap between a rotating gravure cylinder and an engraving head for engraving the surface of the cylinder.

[0002]

2. Description of the Related Art A gravure engraving machine is an apparatus for forming a concave point (cell) on a surface of a cylindrical gravure cylinder using a diamond tool called a stylus while rotating the gravure cylinder. In this device, a cell having a depth (volume) corresponding to an image signal is formed line by line in a continuously rotating cylinder by vibrating a stylus at a frequency of several kHz. In this case, the stylus amplitude is about ± 30 μm, and the cell depth is 50 μm at the maximum.
It is about. On the other hand, since the rotational runout of the gravure cylinder is about several tens of μm, it is impossible to engrave a cell of an accurate size unless the engraving head is moved according to the rotational runout of the gravure cylinder.

For this purpose, as shown in Japanese Patent Publication No. 3-26123, a contact surface (shoe) is provided on the engraving head, and the shoe is pressed against the cylinder surface by a spring or the like to thereby form a gap between the engraving head and the cylinder surface. Is kept constant. However, in such a conventional method of controlling the gap between the engraving head and the cylinder surface, the cylinder may be damaged because the shoe tip is always in contact with the cylinder surface. Further, when the shoe is worn or chipped, the gap is disturbed, and it is difficult to stably and accurately adjust the gap for a long period of time.

An object of the present invention is to enable a gap between an engraving head and a cylinder surface to be accurately adjusted for a long time without using a shoe.

[0005]

A gap control device for a gravure engraving machine according to claim 1 is a device for adjusting a gap between a rotating gravure cylinder and an engraving head for engraving the surface of the cylinder. It comprises a head moving means, a gap detecting means, a judging means and a control means. The head moving means is means for moving the engraving head toward or away from the gravure cylinder at at least two different speeds . The gap detecting means approaches or separates from the gravure cylinder together with the engraving head, and detects the gap between the gravure cylinder and the cylinder surface in a non-contact manner. Judgment means is the sculpture head.
Is within a predetermined distance of the gravure cylinder
Judge. The control means is based on a result of the judgment by the judgment means.
The engraving head is at a predetermined distance from the gravure cylinder.
If it is farther away, the engraving head moves at high speed,
And the engraving head is within a specified distance from the gravure cylinder
The head so that the engraving head moves slowly.
In addition to controlling the moving means, the head moving means is controlled such that the gap between the gravure cylinder and the engraving head has a predetermined value based on the detection result of the gap detecting means. Contract
The gap adjusting device of the gravure engraving machine according to claim 2,
Rolling gravure cylinder and engraving the surface of this cylinder
Device to adjust the gap between the head and the engraving head
The head support member, the first and second head moving means,
It is provided with cap detection means and control means. The head
The support member moves the engraving head toward and away from the gravure cylinder
In the direction of movement. The first head moving hand
The step moves the head support member closer to the gravure cylinder.
Or separate. The second head moving means includes an engraving head.
The head is moved with respect to the head support
The engraving head moves closer to or away from the gravure cylinder.
Let The gap detecting means is provided together with the engraving head.
Approaching or moving away from the gravure cylinder,
Gap between the gravure cylinder without contacting the Linda
To detect. The control means detects the result of the gap detection means.
Head support member from the gravure cylinder
The first header to position a first predetermined distance away position
Control the moving means and then move the engraving head
Position at a second predetermined distance from the
The second head moving means is controlled.

[0006]

In the gap adjusting device for a gravure engraving machine according to the first aspect , a gap detecting means which approaches or separates from the gravure cylinder together with the engraving head is provided. A gap with the cylinder surface is detected. On the basis of the detection result of the gap detecting means, the control means moves the engraving head toward or away from the gravure cylinder so that the gap between the gravure cylinder and the engraving head becomes a predetermined value.

As described above, since the gap detecting means detects the gap between the cylinder surface and the cylinder surface without contacting the cylinder surface, the gap between the engraving head and the cylinder surface can be stably adjusted for a long period of time without using a shoe. I do. Also,
When moving the engraving head, the engraving head
Engraving head if it is more than a predetermined distance from the
Moves at high speed and the engraving head moves against the gravure cylinder.
If it is within a predetermined distance, the engraving head moves at a low speed. here
Now, it is possible to achieve both high accuracy and reduced gap adjustment time.
You. A gap adjusting device for a gravure engraving machine according to claim 2.
Then, the head supporting member is grouped by the first head moving means.
The gravure cylinder is moved toward or away from the gravure cylinder. Ma
The engraving head is supported by the second head moving means.
The engraving head
Is moved toward or away from the gravure cylinder
You. Then, based on the detection result of the gap detection means,
The head support member is separated from the gravure cylinder by a first predetermined distance.
Controlled to be positioned at
The position where the head is separated from the gravure cylinder by the second predetermined distance
Is controlled so as to be positioned. Here,
In the same way, without using a shoe,
Performs movement control by detecting the gap with the surface of the cylinder
Therefore, gap adjustment can be performed stably for a long period of time.

[0008]

1 and 2 show a gravure engraving machine employing an embodiment of the present invention. This gravure engraving machine includes a bed 1, a headstock 2 fixed to the upper surface of the bed 1, a tailstock 3 arranged opposite to the headstock 2, a first table 4 and a second table 5. ing. On a top surface of the bed 1, a pair of guide rails 6 for guiding the tailstock 3;
A pair of guide rails 7 for guiding the tables 4 and 5 are arranged in parallel in the left-right direction. 1 below tailstock 3
A ball screw 8 is arranged between the pair of guide rails 6 in parallel with the guide rails 6, and a nut (not shown) provided below the tailstock 3 is screwed into the ball screw 8. ing. At the end of the ball screw 8 on the side of the bed 1
A drive mechanism 9 including a drive motor and a belt is disposed. The drive mechanism 9 allows the tailstock 3 to approach or separate from the headstock 2.

A spindle 10 is rotatably provided at the center of the headstock 2. The spindle 10 has a drive mechanism 11 including a drive motor and a belt provided on one end side of the headstock 2.
Is to be rotated. On the other hand, a center 12 is disposed at the center of the tailstock 3 so as to be able to protrude and retract and rotate freely. A drive cylinder 13 is mounted on a side portion of the tailstock 3, and the center 12 can be protruded and retracted by the cylinder 13. The gravure cylinder C is supported between the main shaft 10 and the center 12.

The first table 4 and the second table 5 are movable left and right along the guide rail 7. A ball screw 15 is arranged between the pair of guide rails 7 in parallel with the rails 7. A nut (not shown) screwed to the ball screw 15 is fixed to a lower portion of each of the tables 4 and 5. A drive motor 16 is fixed to one end of the ball screw 15. By rotating the ball screw 15 by the drive motor 16, the first table 4 and the second table 5 can be moved in the left-right direction along the guide rail 7.

The first and second tables 4 and 5 are provided with a pair of guide rails 20 as shown in FIG. The guide rail 20 extends in the front-rear direction orthogonal to the guide rail 7. A head support 21 that supports the engraving head is movably mounted on the guide rail 20. On the other hand, between the pair of guide rails 20, a ball screw 22 is arranged in parallel with the guide rails 20,
At one end thereof, a stepping motor 23 for rotating the ball screw 22 is provided. A nut portion screwed to the ball screw 22 is fixed to a lower portion of the head support 21. With such a configuration, it is possible to move the head support 21 in the front-rear direction of the apparatus to approach or move away from the gravure cylinder.

FIG. 4 shows a front view of the head support 21 and FIG. 5 shows a longitudinal sectional view thereof. The head support 21 is formed in a box shape having an opening at a front part. A head support member 25 is inserted inside the head support member 25, and the upper, lower, left and right portions of the head support member 25 are supported by the head support base 21 by leaf springs 26. For this reason, the head support member 25 can move within a predetermined range in the front-rear direction with respect to the head support base 21. An engraving head 27 is fixed to a front portion of the head support member 25. On the upper part of the engraving head 27, a stylus 28 having a diamond bite is mounted. In addition, a gap sensor 29 is arranged at the same height position as the stylus 28 on the front surface of the head support member 25. Therefore, this gap sensor 29 can also approach or separate from the gravure cylinder. The gap sensor 29 is a sensor that faces the cylinder surface in a non-contact manner and detects a gap d between the cylinder surface and the cylinder surface. This sensor is constituted by a capacitance type displacement sensor or an optical type displacement sensor. In the vicinity of the gap sensor 29, a proximity switch 42 that can approach or separate from the gravure cylinder is arranged. The proximity switch 42 is used to determine the distance to the cylinder surface (gap sensor 29).
Is a switch that outputs an ON signal when a gap d that is much longer than the gap d detected with the cylinder surface reaches a set value, and is configured by an optical displacement sensor.

On the other hand, behind the head support member 25, a voice coil motor 30 for moving the head support member 25 in the front-rear direction is arranged. FIG. 6 shows a control block diagram relating to the gap control of the present apparatus. The signal from the gap sensor 29 is input to the A / D converter 32 via the amplifier 31. The gap data converted into a digital signal by the A / D converter 32 is supplied to a DSP.
(Digital signal processor) 33. The DSP 33 has a memory 34 for storing data.
Is connected. The calculation result of the DSP 33 is input to a voice coil motor driver 36 for driving the voice coil motor 30 via a D / A converter 35. The output signal of the voice coil motor driver 36 is input to the voice coil motor 30 so that the engraving head 2
7 can be moved toward or away from the cylinder. Further, the apparatus is provided with a main body control unit 40 for controlling the entire engraving machine. This main body control unit 40
It includes a stepping motor controller and the like. Control data is sent from the main body control unit 40 to the DSP 33, and control data is sent to a stepping motor driver 41 for driving the stepping motor 23. The stepping motor driver 41 drives the stepping motor 23 to move the head support 21 toward or away from the cylinder. An ON signal from the proximity switch 42 is input to the main body control unit 40 via the amplifier 43.

In such an apparatus, a cylindrical gravure cylinder is rotatably supported by a main shaft 10 and a center 12. Then, at the time of engraving, the main shaft 10 is rotated by the drive mechanism 11, thereby rotating the gravure cylinder. In this state, the first and second tables 4 and 5 and the head support 21 are moved to predetermined positions, and the tables 4 and 5 are moved laterally while the stylus is driven to engrave the gravure cylinder surface.

Next, the control operation of the present apparatus will be described with reference to the flowcharts shown in FIGS. When the start switch of the device is turned on, first, in step S1, initialization is performed. In this initial setting, processing such as moving each unit to an initial position or resetting a flag is performed. Next, in step S2, it is determined whether the cell monitor mode has been selected. The cell monitor mode is a mode for engraving a gravure cylinder on a trial basis and adjusting the cell depth. Also,
In a step S3, it is determined whether or not the gap designation is selected, and in a step S4, it is determined whether or not an engraving command is issued. If NO is determined in steps S2 to S4, the process shifts to step S5 to perform another process and returns to step S2.

When the cell monitor mode is selected,
The program proceeds from step S2 to step S6. In step S6, a process of engraving a pilot cell on a trial basis in the non-image forming area of the gravure cylinder is executed. If the gap designation is selected, step S
The process moves from step 3 to step S7. In step S7, the operator inputs the optimum gap values G ₁ and G ₂ between the engraving head and the cylinder surface with reference to the results obtained in the cell monitor mode and the like. Further, when an engraving start command is issued, the process shifts from step S4 to step S8 to execute engraving processing.

In the engraving process, a start signal is first sent to the DSP 33 in step S10 as shown in FIG. Next, in step S11, the stepping motor driver 41 is instructed to turn on the stepping motor. Thereby, the head support 21 moves forward so as to approach the gravure cylinder. At this time, the head support 21 is sent at a high speed.

Next, in steps S12a to S12c,
It is determined whether or not the feed speed of the head support 21 has reached a position for switching from high speed to fine speed. That is, in step S12a, a signal from the proximity switch 42 is input, and whether or not the signal is an ON signal is determined in step S12a.
Judge at 12b. If the signal from the proximity switch 42 is not an ON signal, it is determined that the feed speed has not been reached, and steps S12a and S12b are repeated. On the other hand, when the signal from the proximity switch 42 is an ON signal, it is determined that the position for switching the feed speed has been reached, the switching flag is switched from OFF to ON in step S12c, and the control operation proceeds to the subsequent step S13. . In step S13, the stepping motor 2
The feed speed of 3 is changed over to the fine feed.

[0019] In step S14, it is determined whether it is the value G ₁ a gap is designated between the engraving head 27 and the gravure cylinder while continuing the fine speed feed. This determination is made based on a signal input from the gap sensor 29 to the DSP 33, and is determined based on whether the gap 1 setting completion flag in the DSP 33 has been turned on. When the gap sensor 29 detects that the gap between the engraving head 27 and the cylinder has reached the set value, the gap 1 setting completion flag is turned on in the DSP 33. In this case, steps S14 to S14 are performed. Move to S15. In step S15, the stepping motor 23 is turned off. Thereby, the advance of the head support 21 is stopped.

In this manner, the engraving head 27 and the gravure
A predetermined gap G between the cylinder ₁Where it became
Move to step S16. In this step S16,
Drive the stylus 28 to engrave the gravure cylinder
Let the time work. In step S17, is the engraving completed?
It is determined whether or not the process is completed.
Run. In step S18, the engraving completion flag is turned on.
You. This is a flow for stopping the control by the DSP 33.
It is a lag.

When the engraving process is completed, the stepping motor is turned on in step S19 and the head support 21
Retreat. At this time, the head support 21 is moved backward at high speed. In step S20, the head support 21
Is determined to be near the initial position (origin), and if so, the process proceeds to step S21. In step S21, the stepping motor 23 is decelerated. Then, in a step S22, it is determined whether or not the head support 21 has reached the origin. In step S20 and step S22, whether or not the head support 21 has reached the vicinity of the origin and the origin is determined by counting a signal from a limit switch or a pulse from an encoder. If it is determined in step S22 that the head support 21 has reached the origin, the process proceeds to step S23. In step S23, the stepping motor 23 is turned off.

Next, the control operation of the DSP 33 will be described. When the start switch of the apparatus is turned on, initialization is performed in step P1 of FIG. Next, step P2
Then, it waits for a start signal to be sent from the main body control unit 40. When an engraving start command is issued by the main body control unit 40, a start signal is sent to the DSP 33 side.

The DSP 33 receives the start signal and switches
The process proceeds to Step P3. In step P3, servo control
Turn on. At this time, the voice coil motor 3
0 servo control is locked and therefore the head
The support member 25 does not move. Next, in Step P4, the book
The gap input in step S7 of the body control unit 40
G ₁, G_TwoRead the data of.

Next, at step P8, the gap sensor 2
Input the data from # 9. And in step P9,
The data from the gap sensor 29, which determines if the value G ₁ a gap is specified. If it is determined that the gap has reached a predetermined value, the process proceeds to step P
Move to 10. Then, in this step P10, the gap 1 setting completion flag is turned on. Thus, the main body control unit 40 performs control to stop the stepping motor 23.

Next, in step P11, the engraving head 27
And performing PID control such that a gap is G ₂ between the gravure cylinder. In this PID control, as shown in FIG. 10, first, in step P15, the integral value I _{0 is set} to “0”, and the gap data initial value d _{0 is set} to “0”. Next, in step P16, the gap data d from the gap sensor 29 is read. And in step P17,
The error e is calculated based on the equation e = d−d ₀ . Next, in Step P18,
The calculation of the proportional operation is performed on the basis of P = Kp × eKp: proportional operation gain. In Step P19, calculation of the integration operation is performed based on I = I ₀ + Ki × e Ki: corresponding to the integration operation gain. Further, in step P20, the calculation of the differential operation is performed based on D = Kd × (d ₀ −d) where Kd is the differential operation gain. In step P21, (P + I + D)
Is output to the D / A converter 35. Then step P
At 22, I is set to I ₀ and d is set to d ₀ . Next, in Step P23, it is determined whether or not the engraving has been completed.
This determination is made based on whether the engraving completion flag is turned on in the main body control unit 40 or not. Until the engraving is completed, the processes from Step P16 to Step P23 are repeatedly executed. When the engraving is completed and the engraving completion flag is turned on in the main body control unit 40, the process exits from the process and proceeds to step P25 in FIG. In Step P25, the servo control is turned off, each flag is reset, and the process returns to Step P2.

In this embodiment, the gap between the gravure cylinder and the head can be adjusted accurately and in a short time because the engraving head 27 is automatically moved to an appropriate position at a high speed and a low speed. In particular, it is possible to quickly cope with a case where cylinders having different diameters are mounted. Further, in the present embodiment, since the rotational runout of the cylinder surface is detected by the non-contact type gap sensor 29, it is possible to prevent the cylinder surface from being damaged. Further, since the gap sensor 29 is mounted at the same height position as the stylus, the gap between the stylus and the cylinder surface can be adjusted to a desired gap with high accuracy.

[Other Embodiments] (a) In the above-described embodiment, the head support member 25 is supported by the leaf spring 26 with respect to the head support base 21. May be. (B) In the above embodiment, the voice coil motor 30 is used to move the head support member 25 in the front-rear direction. However, other driving means, for example, a piezo element or the like may be used.

[0028]

As described above, according to the present invention, the gap between the engraving head and the cylinder surface is detected by the non-contact type detecting means, and the engraving head is moved so that the gap is constant. The gap between the cylinder surface and the engraving head can be accurately adjusted without damaging the cylinder surface. Also,
When moving the engraving head,
At high speed until it reaches the specified distance from the surface of the
When the distance becomes constant, the robot moves at a low speed, so adjust the gap.
Shortening of processing time and high accuracy can be achieved at the same time.

[Brief description of the drawings]

FIG. 1 is a front view of a gravure engraving machine employing one embodiment of the present invention.

FIG. 2 is a plan view of the gravure engraving machine.

FIG. 3 is a perspective view of a first table portion of the gravure engraving machine.

FIG. 4 is a front view of an engraving head mounting portion of the gravure engraving machine.

FIG. 5 is a vertical sectional configuration diagram of the engraving head mounting portion.

FIG. 6 is a control block diagram of the device.

FIG. 7 is a flowchart of a main body control unit.

FIG. 8 is a control flowchart of an engraving process of a main body control unit.

FIG. 9 is a control flowchart of a DSP.

FIG. 10 is a flowchart of PID control of the DSP.

[Explanation of symbols]

 23 Stepping motor 27 Engraving head 29 Gap sensor 30 Voice coil motor 33 DSP 40 Main unit control unit

Continuation of the front page (72) Inventor Tadashi Shuto 4-chome Tenjin, Horikawa-dori-Terauchi, Kamigyo-ku, Kyoto 1 1-Dai Nippon Screen Manufacturing Co., Ltd. (56) References JP-A-4-138253 ( JP, A) JP-A-2-110413 (JP, A) JP-A-4-26726 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) B41C 1/00-1/18

Claims (2)

(57) [Claims] 1. A gap control device for a gravure engraving machine for adjusting a gap between a rotating gravure cylinder and an engraving head for engraving a surface of the cylinder, wherein the engraving head is moved relative to the gravure cylinder. Few
A head moving means for approaching or moving away from the gravure cylinder at least at two different speeds, and moving toward or away from the gravure cylinder together with the engraving head, and detecting a gap between the gravure cylinder without contacting the gravure cylinder. Gap detecting means, and the engraving head is a predetermined distance from the gravure cylinder.
Determining means for determining whether the engraving head is within the range, and based on the determination result of the determining means,
Separated from the gravure cylinder by the predetermined distance or more.
If the engraving head moves at high speed,
The engraving head is at the predetermined distance from the gravure cylinder
So that the engraving head moves at low speed
Control means for controlling the head moving means and controlling the head moving means so that the gap between the gravure cylinder and the engraving head becomes a predetermined value based on the detection result of the gap detecting means. Gap control device. 2. Rotating gravure cylinder and this cylinder
Adjust the gap between the engraving head for engraving the surface
A gap control device for a gravure engraving machine, wherein the engraving head is moved toward and away from the gravure cylinder.
A head support member movably supporting the head support member in a direction to contact the gravure cylinder.
First head moving means for moving the engraving head closer to or away from the head support member;
By moving the engraving head to the gravure cylinder
A second head moving means for approaching or moving away from the gravure cylinder together with the engraving head
Approaching or away, before a non-contact before Symbol gravure cylinder
Gap to detect the gap between the gravure cylinder
Based on the detection result of the gap detection means and the gap detection means.
Distance between the gravure cylinder and the gravure cylinder by a first predetermined distance.
The first head moving means so as to position the first head
And then engraving the engraving head with the gravure
Before positioning at a second predetermined distance from the
A gap control device for a gravure engraving machine , comprising: control means for controlling the second head moving means .