JP2021050088A - Winding device - Google Patents

Abstract

To reduce decline in web winding quality.SOLUTION: A winding shaft 43 winds a web W. A winding motor 44 rotates the winding shaft 43. A braking part 61 imparts breaking force to the web W wound on the winding shaft 43. A dancer roller 53 is provided on the upstream side of the braking part 61 in the transport direction of the web W and pushes the web W by its self weight. A controlling part 5 controls so that the winding motor 44 rotates the winding shaft 43 with the braking part 61 on, causing the winding shaft 43 to wind up the web W thereon. Furthermore, the controlling part 5 turns the braking part 61 off with the winding motor 44 in the locked condition when the winding of the web W onto the winding shaft 43 is stopped.SELECTED DRAWING: Figure 3

Description

The present invention relates to a winding device for winding a web.

A printing device that prints on the web while transporting a long web as a printing medium is known.

In such a printing apparatus, the printed web is wound around the take-up shaft by rotating the take-up shaft with a motor (see Patent Document 1).

Japanese Unexamined Patent Publication No. 2017-25586

In the printing device described above, even if the motor is stopped to finish the winding of the web, the inertia of the winding roll formed by the web wound on the winding shaft causes the gear and the winding shaft of the motor to be connected. The take-up roll and take-up shaft continue to rotate by the amount of backlash between the gears. As a result, the web is additionally wound around the winding shaft.

After that, when the inertia of the take-up roll disappears, the take-up roll rotates in the reverse direction by the amount of backlash between the gear of the motor and the gear of the take-up shaft due to the tension of the web. As a result, slack in the web occurs on the upstream side of the take-up roll in the transport direction of the web.

If the web is slack for a long time, the web of the take-up roll may loosen and the take-up quality may deteriorate. For example, the take-up roll may have lateral displacement of the web, and the end face of the take-up roll may have irregularities.

The present invention has been made in view of the above, and an object of the present invention is to provide a winding device capable of reducing deterioration in winding quality of a web.

In order to achieve the above object, the winding device of the present invention comprises a winding shaft for winding a web, a motor for rotating the winding shaft, and a brake for applying a braking force to the web wound around the winding shaft. The control unit includes a unit and a control unit that controls the winding shaft to wind the web by rotating the winding shaft by the motor while the brake unit generates a braking force. When the winding of the web to the winding shaft is stopped, the motor is locked, the brake portion is turned off, the winding of the web to the winding shaft is stopped, and the motor is locked. When the brake portion is turned off, the web between the take-up shaft and the brake portion is pulled upstream in the transport direction of the web wound around the take-up shaft.

According to the winding device of the present invention, it is possible to reduce the deterioration of the winding quality of the web.

It is a block diagram which shows the structure of the printing apparatus which concerns on embodiment. It is a schematic block diagram of the main part of the printing apparatus shown in FIG. It is an enlarged view of the winding part of the printing apparatus shown in FIG. It is explanatory drawing of the process in which the slack of the web occurs in a winding part. It is explanatory drawing of the process in which the slack of the web occurs in a winding part. It is explanatory drawing of the process in which the slack of the web occurs in a winding part. It is a flowchart for demonstrating the slack elimination operation. It is explanatory drawing of the slack elimination operation. It is explanatory drawing of the slack elimination operation. It is explanatory drawing of the slack elimination operation.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The same or equivalent parts and components are designated by the same or equivalent reference numerals throughout the drawings.

The embodiments shown below exemplify an apparatus or the like for embodying the technical idea of the present invention, and the technical idea of the present invention includes the material, shape, structure, arrangement, etc. of each component. Is not specified as the following. The technical idea of the present invention can be modified in various ways within the scope of claims.

FIG. 1 is a block diagram showing a configuration of a printing device including a winding device according to an embodiment of the present invention. FIG. 2 is a schematic configuration diagram of a main part of the printing apparatus shown in FIG. FIG. 3 is an enlarged view of a take-up portion of the printing apparatus shown in FIG. In the following description, the direction orthogonal to the paper surface of FIG. 2 is the front-back direction, and the front direction of the paper surface is the front. Further, the vertical and horizontal directions of the paper surface in FIG. 2 are defined as the vertical and horizontal directions.

As shown in FIG. 1, the printing apparatus 1 according to the present embodiment includes a web roll holding unit 2, a transport printing unit 3, a winding unit 4, and a control unit 5. The take-up device is composed of the take-up unit 4 and the control unit 5 of the printing device 1.

The web roll holding unit 2 holds the web roll 6. The web roll 6 is a roll of web W, which is a long printing medium made of a film, paper, or the like. The web roll holding portion 2 includes a web roll support shaft 11 and a brake portion 12.

The web roll support shaft 11 rotatably supports the web roll 6. The web roll support shaft 11 is formed in an elongated shape extending in the front-rear direction.

The brake unit 12 applies tension to the web W between the web roll 6 and the transport roller 26, which will be described later, by braking the rotation of the web roll support shaft 11. The brake unit 12 is made of, for example, a powder brake.

The transport printing unit 3 prints on the web W while transporting the web W. The transport printing unit 3 includes a transport unit 21 and printing units 22A and 22B.

The transport unit 21 transports the web W while pulling out the web W from the web roll 6. The transport unit 21 includes a pair of transport rollers 26 and a transport motor 27.

The pair of transfer rollers 26 convey the web W toward the take-up unit 4 while niping the web W. By transporting the web W by the transport roller 26, the web roll 6 rotates together with the web roll support shaft 11, and the web W is pulled out from the web roll 6.

The transfer motor 27 rotates the transfer roller 26.

The printing units 22A and 22B print on the front surface and the back surface of the Web W, respectively. The printing units 22A and 22B each include five head units 31.

The head unit 31 has an inkjet head (not shown), and ejects ink from the inkjet head to the web W to print an image. In each of the printing units 22A and 22B, the five head units 31 eject inks of different colors.

The winding unit 4 winds up the web W printed by the printing units 22A and 22B. The take-up unit 4 includes a buffer unit 41, a tension roller mechanism unit 42, a take-up shaft 43, and a take-up motor (corresponding to a motor) 44.

The buffer unit 41 holds the slack of the web W between the transport unit 21 and the tension roller mechanism unit 42. The buffer portion 41 is arranged on the upstream side of the tension roller mechanism portion 42 in the transport direction of the web W. The buffer portion 41 includes guide rollers 51 and 52, a dancer roller 53, a carriage 54, a guide shaft 55, and a dancer position sensor 56.

The guide rollers 51 and 52 guide the web W between the transport unit 21 and the tension roller mechanism unit 42.

The dancer roller 53 pushes down the web W by its own weight between the guide rollers 51 and 52. As a result, the slack of the web W between the transport unit 21 and the tension roller mechanism unit 42 is absorbed by the buffer unit 41. The dancer roller 53 moves up and down due to fluctuations in the amount of slack in the web W between the transport unit 21 and the tension roller mechanism unit 42.

The carriage 54 rotatably holds the dancer roller 53. The carriage 54 moves up and down along the guide shaft 55 together with the dancer roller 53.

The guide shaft 55 guides the ascending / descending carriage 54. The guide shaft 55 is inclined so as to be lower toward the right side. As a result, the winding portion 4 is reduced in height and miniaturized. The guide shaft 55 may be installed in parallel in the vertical direction without being inclined.

The dancer position sensor 56 detects the position of the dancer roller 53 on the guide shaft 55. That is, the dancer position sensor 56 detects the height position of the dancer roller 53.

The tension roller mechanism 42 applies tension to the web W wound around the take-up shaft 43. The tension roller mechanism portion 42 includes a brake portion 61 and guide rollers 62 and 63.

The brake unit 61 applies tension to the web W by applying a braking force to the web W wound around the take-up shaft 43. The brake portion 61 is arranged on the upstream side of the take-up shaft 43 (wind-up roll 66) in the transport direction of the web W. The brake unit 61 has a brake roller 61a. The web W is wound around the brake roller 61a. The brake unit 61 applies a braking force to the web W by applying a brake to the rotation of the brake roller 61a. The brake unit 61 is made of, for example, a powder brake.

The guide rollers 62 and 63 assist in winding the web W around the brake roller 61a.

The take-up shaft 43 winds up and holds the web W. The take-up roll 66 is formed by the web W wound around the take-up shaft 43. The take-up shaft 43 is formed in a long shape extending in the front-rear direction. A take-up shaft gear 43a is fixed to the take-up shaft 43.

The take-up motor 44 rotates the take-up shaft 43 in the clockwise direction in FIG. The rotation of the take-up shaft 43 causes the web W to be taken up by the take-up shaft 43.

The take-up motor 44 has an output shaft 44a that outputs a rotational driving force. An output gear 44b is attached to the output shaft 44a. The output gear 44b meshes with the take-up shaft gear 43a. As a result, the rotational driving force of the take-up motor 44 is transmitted from the output gear 44b to the take-up shaft gear 43a, so that the take-up shaft 43 rotates.

The control unit 5 controls the operation of the entire printing device 1. The control unit 5 includes a CPU, RAM, ROM, a hard disk, and the like.

When printing, the control unit 5 rotationally drives the transfer roller 26 by the transfer motor 27 while the brake unit 12 generates a braking force, and the transfer roller 26 transfers the web W while pulling it out from the web roll 6. Control to do. Further, the control unit 5 controls the take-up shaft 43 to take up the web W by rotating the take-up shaft 43 by the take-up motor 44 while the brake unit 61 is on. Then, the control unit 5 causes the conveyed web W to print an image by ejecting ink from the head units 31 of the printing units 22A and 22B.

Further, the control unit 5 executes a slack eliminating operation, which will be described later, at the end of the printing operation.

Next, the printing operation of the printing device 1 will be described.

When the print job is input, the control unit 5 starts driving the transfer motor 27 and the take-up motor 44 to start the transfer of the web W. Here, the brake units 12 and 61 remain on from the standby state. In the printing device 1, the brake units 12 and 61 are turned on during standby to maintain the tension of the web W and prevent the occurrence of slack.

When the transport of the web W is started, the control unit 5 accelerates the transport speed of the web W by the transport roller 26 at a predetermined acceleration from the start of the transport.

After that, when the transport speed of the web W by the transport roller 26 reaches a predetermined print transport speed, the control unit 5 shifts to the constant speed transport of the web W at the print transport speed from that point, and the transport motor 27 and the winding. Controls the take-up motor 44.

After starting the constant speed transfer of the Web W at the print transfer speed, the control unit 5 starts printing by the printing units 22A and 22B based on the print job.

After the start of constant speed transfer of the web W at the print transfer speed, the control unit 5 prints the transfer speed of the web W based on the output pulse signal of the encoder (not shown) provided in the transfer motor 27. The transport motor 27 is controlled so as to maintain a constant value.

Further, the control unit 5 controls the take-up motor 44 so that the height position of the dancer roller 53 detected by the dancer position sensor 56 maintains a predetermined target position, and winds the web W by the take-up shaft 43. Control the take speed. Here, the target position of the dancer roller 53 is set near the center of the range in which the dancer roller 53 can move along the guide shaft 55.

When the printing based on the print job is completed, the control unit 5 stops the transfer motor 27 and the take-up motor 44 to stop the transfer of the web W. As a result, a series of printing operations is completed.

Here, when the take-up motor 44 is stopped at the end of the above-mentioned printing operation to stop the take-up operation by the take-up unit 4, the take-up shaft 43 (take-up roll 66) and the tension roller mechanism of the take-up unit 4 are stopped. The web W is slackened with the portion 42 (brake portion 61). The reason why the slack of the web W in the winding unit 4 occurs will be described.

During the winding operation, as shown in FIG. 4, the output shaft 44a and the output gear 44b of the winding motor 44 rotate counterclockwise when viewed from the front side. As a result, the take-up shaft gear 43a and the take-up shaft 43 rotate clockwise when viewed from the front side, and the web W is taken up by the take-up shaft 43 (winding roll 66).

When the take-up motor 44 is stopped at the end of the take-up operation, the rotation of the output shaft 44a and the output gear 44b is stopped. Then, the take-up motor 44 is locked. The locked state of the take-up motor 44 is a state in which the take-up motor 44 cannot rotate, and more specifically, a state in which the output shaft 44a and the output gear 44b do not rotate even when an external force is applied.

However, due to the inertia of the take-up roll 66, as shown in FIG. 5, the amount of backlash between the output gear 44b and the take-up shaft gear 43a (when the output gear 44b and the take-up shaft gear 43a mesh with each other) The take-up roll 66 and the take-up shaft 43 continue to rotate by the amount of the gap between the two gears. As a result, the web W is excessively wound around the winding shaft 43.

After that, when the inertia of the take-up roll 66 disappears, as shown in FIG. 6, the take-up roll 66 is reversed by the amount of backlash between the output gear 44b and the take-up shaft gear 43a due to the tension of the web W. Rotate. As a result, the web W is slackened between the winding shaft 43 (winding roll 66) of the winding portion 4 and the tension roller mechanism portion 42.

The printing device 1 executes a slack eliminating operation for eliminating the slack of the web W in the winding unit 4 that occurs as described above. This slack eliminating operation will be described with reference to the flowchart of FIG. 7.

In step S1 of FIG. 7, the control unit 5 stops the take-up motor 44 in order to end the take-up operation, and puts the take-up motor 44 into the locked state described above. As a result, as described above, the web W is slackened between the winding shaft 43 (winding roll 66) and the tension roller mechanism portion 42. At this time, as shown in FIG. 8, the brake portion 61 remains on during the winding operation. Further, the dancer roller 53 is near the above-mentioned target position.

Returning to FIG. 7, in step S2, the control unit 5 turns off the brake unit 61. As a result, the braking force of the brake portion 61 is lost, and as shown in FIG. 9, the dancer roller 53 pushes down the web W by its own weight. As a result, the web W between the take-up shaft 43 (wind-up roll 66) and the brake portion 61 is pulled upstream. Then, as the dancer roller 53 descends, the amount of slack in the web W gradually decreases, and the slack is eliminated. When the slack of the web W is eliminated, the dancer roller 53 stops descending and the position of the dancer roller 53 does not change.

Returning to FIG. 7, in step S3, the control unit 5 determines whether or not the position of the dancer roller 53 has not changed based on the detection output of the dancer position sensor 56. Here, the control unit 5 determines that the position of the dancer roller 53 has not changed when a predetermined determination time elapses while the position of the dancer roller 53 detected by the dancer position sensor 56 is constant. The determination time is set in advance as a time for determining that the descent of the dancer roller 53 has been completed. When it is determined that the position of the dancer roller 53 has changed (step S3: NO), the control unit 5 repeats step S3.

When it is determined that the position of the dancer roller 53 has not changed (step S3: YES), the control unit 5 turns on the brake unit 61 in step S4. As a result, as shown in FIG. 10, the brake portion 61 is turned on with the slack of the web W between the take-up shaft 43 (winding roll 66) and the tension roller mechanism portion 42 eliminated, and a series of operations is performed. It will be the end.

As described above, in the printing device 1, when the control unit 5 stops the winding motor 44 and stops the winding of the web W to the winding shaft 43, the control unit 5 locks the winding motor 44 and brakes the unit. 61 is turned off. As a result, the braking force of the brake portion 61 is lost, and the dancer roller 53 pushes down the web W by its own weight, pulling the web W between the take-up shaft 43 (winding roll 66) and the brake portion 61 upstream. .. As a result, the slack of the web W between the take-up shaft 43 (wind-up roll 66) and the brake portion 61 is eliminated. As a result, it is possible to reduce the deterioration of the winding quality such as the lateral displacement of the web W due to the loosening of the web W of the winding roll 66.

Further, the control unit 5 stops the winding of the web W on the winding shaft 43, locks the winding motor 44, turns off the brake unit 61, and then turns on the brake unit 61. As a result, the tension of the web W can be maintained even while the printing apparatus 1 is on standby to suppress the occurrence of slack.

Further, in the control unit 5, when the brake unit 61 is turned off, the dancer roller 53 pushes down the web W by its own weight and pulls the web W upstream, so that the web W between the take-up shaft 43 and the brake unit 61 When the slack is eliminated, that is, when the dancer roller 53 stops descending, the brake portion 61 is turned on. As a result, it is possible to prevent insufficient elimination of the slack of the web W between the take-up shaft 43 and the brake portion 61.

In the above-described embodiment, in the slack eliminating operation, the control unit 5 determines that the position of the dancer roller 53 does not change based on the detection output of the dancer position sensor 56 after the brake unit 61 is turned off. , The brake unit 61 was turned on. However, after the brake unit 61 is turned off, the brake unit 61 may be turned on when a predetermined time preset as a sufficient time for eliminating the slack of the web W has elapsed.

Further, in the slack eliminating operation, it may be omitted to turn on the brake unit 61 after turning off the brake unit 61. Even in this case, it is possible to eliminate the slack of the web W and reduce the deterioration of the winding quality.

In the above-described embodiment, in the slack eliminating operation, the dancer roller 53 pushes down the web W by its own weight and pulls the web W to eliminate the slack of the web W, but the present invention is not limited to this. For example, by providing a pulling roller on the upstream side of the brake portion 61 and pulling up the web W with this pulling roller, the slack of the web W between the take-up shaft 43 (winding roll 66) and the brake portion 61 is eliminated. You may try to do it. The amount by which the pulling roller pulls up the web W is an amount that can eliminate the slack of the web W between the take-up shaft 43 (winding roll 66) and the brake portion 61 and does not pull the web W excessively. You can ask for it.

Further, the transport motor 27 and the take-up motor 44 may be controlled so that the dancer roller 53 is arranged at a predetermined upper limit position higher than the target position at the end of transport of the web W. As a result, the web W held by the buffer unit 41 is reduced, so that the web W extraly drawn from the web roll 6 is reduced. As a result, waste (waste paper) of the web W is reduced.

The present invention is not limited to the above-described embodiment as it is, and at the implementation stage, the components can be modified and embodied within a range that does not deviate from the gist thereof. In addition, various inventions can be formed by an appropriate combination of the plurality of components disclosed in the above-described embodiment. For example, some components may be removed from all the components shown in the embodiments.

[Additional Notes]
This application discloses the following inventions.

(Appendix 1)
The winding shaft that winds up the web,
A motor that rotates the take-up shaft and
A brake unit that applies braking force to the web wound around the take-up shaft, and
It is provided with a control unit that controls the winding shaft to wind the web by rotating the winding shaft by the motor in an on state in which the braking unit generates a braking force.
When the control unit stops the winding of the web to the winding shaft, the control unit locks the motor and turns off the brake unit.
When the winding of the web to the take-up shaft is stopped, the motor is locked and the brake portion is turned off, the web between the take-up shaft and the brake portion is taken up. A winding device characterized in that the web is pulled upstream in the transport direction of the web wound around the shaft.

(Appendix 2)
The invention described in Appendix 1, wherein the control unit stops the winding of the web to the winding shaft, locks the motor, turns off the brake unit, and then turns on the brake unit. Winding device.

(Appendix 3)
Further provided with a dancer roller arranged on the upstream side of the brake portion in the transport direction and pushing down the web by its own weight.
In the control unit, when the brake unit is turned off, the dancer roller pushes down the web by its own weight and pulls the web to the upstream side in the transport direction, so that the web slacks between the take-up shaft and the brake unit. The winding device according to Appendix 2, wherein the brake portion is turned on when the problem is solved.

1 Printing device 2 Web roll holding part 3 Conveying printing part 4 Winding part 5 Control part 41 Buffer part 42 Tension roller mechanism part 43 Winding shaft 43a Winding shaft gear 44 Winding motor 44a Output shaft 44b Output gear 51, 52, 62, 63 Guide roller 53 Dancer roller 54 Carriage 55 Guide shaft 56 Dancer position sensor 61 Brake section 61a Brake roller

Claims (3)

The winding shaft that winds up the web,
A motor that rotates the take-up shaft and
A brake unit that applies braking force to the web wound around the take-up shaft, and
It is provided with a control unit that controls the winding shaft to wind the web by rotating the winding shaft by the motor in an on state in which the braking unit generates a braking force.
When the control unit stops the winding of the web to the winding shaft, the control unit locks the motor and turns off the brake unit.
When the winding of the web to the take-up shaft is stopped, the motor is locked and the brake portion is turned off, the web between the take-up shaft and the brake portion is taken up. A winding device characterized in that the web is pulled upstream in the transport direction of the web wound around the shaft. The first aspect of the present invention is characterized in that the control unit stops the winding of the web to the winding shaft, locks the motor, turns off the brake unit, and then turns on the brake unit. The take-up device described. Further provided with a dancer roller arranged on the upstream side of the brake portion in the transport direction and pushing down the web by its own weight.
In the control unit, when the brake unit is turned off, the dancer roller pushes down the web by its own weight and pulls the web to the upstream side in the transport direction, so that the web slacks between the take-up shaft and the brake unit. The winding device according to claim 2, wherein the brake portion is turned on when the problem is solved.

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