JP5291732B2 - Transfer film tension control device and transfer film tension control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve workability upon replacement and attachment of a film supply roll and maintainability. <P>SOLUTION: There are provided a powder clutch 14 that puts a brake on rotation of a supply roll axis 13, a first rotary encoder 15 that detects the number of rotations of the supply roll axis 13, a film feeding roller 23 that feeds a transfer film 3 to a film take-up roll, a second rotary encoder 25 that detects the number of rotations of the film feeding roller 23, and a controlling section 11 that controls the powder clutch 14 on the basis of signals from the first and second rotary encoders 15 and 25. The controlling section 11 calculates a roll diameter of the transfer film 3 wound around a film supply roll 12 and controls the number of rotations of the film supply roll 12 by the powder clutch 14 according to the roll diameter, thereby maintaining a constant tension provided to the transfer film 3 between the film supply roll 12 and the film take-up roll 21. <P>COPYRIGHT: (C)2012,JPO&amp;INPIT

Description

  The present invention relates to a transfer film tension control device and a transfer film tension control method used when a transfer film supplied from a film supply roll is wound on a film take-up roll.

  2. Description of the Related Art There is known a transfer molding apparatus in which a transfer film is sandwiched between molds of an injection molding machine, and a print such as a design of a transfer film printed in advance is transferred to a molded product simultaneously with molding.

  This type of transfer molding apparatus generally includes a film supply device that supplies a transfer film, a film winding device that winds up a transfer film supplied from the film supply device, and a film supply device and a film winding device. And a molding die arranged.

  The film supply apparatus has a supply roll shaft that integrally supports a film supply roll around which a transfer film is wound. The film winding device includes a winding roll shaft that integrally supports a film winding roll that winds a transfer film supplied from a film supply roll, and a servo motor that rotates the winding roll shaft. .

  In addition, the transfer molding device controls the tension generated in the transfer film when the transfer film is positioned with respect to the molding part of the molding die before molding. Called a control device).

  In FIG. 3, the schematic diagram of the tension control apparatus relevant to this invention is shown. As shown in FIG. 3, the tension control device related to the present invention is a brake mechanism (not shown) disposed immediately downstream of the transfer direction of the transfer film 103 drawn from the film supply roll 106 of the film supply device 105. And a pressure roller 111 pressed against the guide roller 110. This tension control device sandwiches the transfer film 103 between the guide roller 110 and the pressing roller 111 and operates the brake mechanism, so that the guide roller 110 against the winding force of the film winding device (not shown). By applying a braking force to the transfer film 103 by the pressing roller 111, the tension generated in the transfer film 103 is kept constant.

  FIG. 4 shows a schematic diagram of a configuration example of another tension control device. FIG. 5 shows a schematic diagram of a configuration example of another tension control device. As another tension control device, as shown in FIGS. 4 and 5, a roll diameter measuring lever 120 is pressed by a spring (not shown) on the peripheral surface of the film supply roll 116 of the film supply device 115, and the roll diameter is reduced. The structure which measures the roll diameter of the film supply roll 116 with the potentiometer 121 connected with the measurement lever 120 is disclosed (refer patent document 1). The tension control device includes a powder clutch 123 that generates a braking force on a supply roll shaft 117 that rotates integrally with the film supply roll 116, and a control unit 124 that controls the operation of the powder clutch 123 based on a signal from the potentiometer 121. And have.

  In this configuration, the control unit 124 calculates the roll diameter of the film supply roll 116 using the measured value by the potentiometer 121, and the powder clutch 123 connected to the supply roll shaft 117 according to the size of the roll diameter. By controlling the magnitude of the braking force, the tension applied to the transfer film 103 is kept constant.

Japanese Patent No. 3211185

  By the way, as described above, the configuration in which the transfer film is sandwiched between the guide roller and the pressing roller to apply a braking force to the transfer film damages the design printed on the transfer film before being transferred to the molded product. There is a risk of causing. In addition, in this configuration, the tension of the transfer film changes due to an effect such as a motor backlash occurring when the winding operation of the winding roll is stopped after the positioning of the transfer film with respect to the molding die is completed. Therefore, it was difficult to keep the tension of the transfer film constant during molding.

  Further, the configuration described in Patent Document 1 requires a mechanical adjustment of the roll diameter measuring lever and an amplifier adjustment of the potentiometer, and there is an inconvenience that a periodic inspection is required. In addition, in the configuration described in Patent Document 1, it is necessary to retract the film roll diameter measuring lever from the film supply roll when the film supply roll is replaced and mounted, and there is a problem that workability is poor.

  Therefore, an object of the present invention is to provide a transfer film tension control device and a transfer film tension control method capable of solving the above-described technical problems.

  An example of the object of the present invention is to make it possible to omit a mechanism for detecting by contacting the transfer film in order to detect the roll diameter of the film supply roll, and to improve workability and maintainability. It is an object of the present invention to provide a tension control device and a transfer film tension control method.

In order to achieve the above-described object, a transfer film tension control device according to the present invention includes a supply roll shaft that supports a film supply roll so as to rotate integrally with a film supply roll around which the transfer film is wound, and a supply roll A film supply device having braking means for braking the rotation of the shaft, and a first rotation detector for detecting the rotation speed of the supply roll shaft;
A take-up roll shaft for supporting the film take-up roll so as to rotate integrally with the film take-up roll for taking up the transfer film supplied from the film supply roll; and a film feed roller for feeding the transfer film to the film take-up roll; A film winding device having a driving means for rotating the film feed roller, and a second rotation detector for detecting the number of rotations of the film feed roller;
Control means for controlling the driving means based on the signal from the second rotation detector and for controlling the braking means based on the signals from the first and second rotation detectors.
Between the film supply roll and the film take-up roll, a transfer unit for transferring the print image of the transfer film to the transfer material is disposed. The film feed roller is disposed at a position between the transfer unit and the film take-up roll. The control means calculates the roll diameter of the transfer film wound around the film supply roll, and controls the number of rotations of the film supply roll by the braking means according to the roll diameter, whereby the film supply roll and the film take-up roll The film supply roll is rotated in the direction in which the transfer film is wound around the film supply roll while the tension applied to the transfer film is kept constant and the winding operation of the film take-up roll is stopped.

The transfer film tension control method according to the present invention includes a film feed amount in which a transfer film is fed by a film feed roller to a film take-up roll that winds a transfer film supplied from a film supply roll, and rotation of the film supply roll. The control means calculates the roll diameter of the transfer film wound around the film supply roll based on the number, and the control means controls the number of rotations of the film supply roll according to the roll diameter. While maintaining the tension applied to the transfer film between the take-up roll and the film take-up roll, when the take-up operation of the film take-up roll is stopped, the film supply roll in the direction of winding the transfer film onto the film supply roll. Is controlled to rotate .

  According to the present invention, it is possible to omit a mechanism for detecting by contacting the transfer film in order to detect the roll diameter of the film supply roll, workability at the time of replacement and mounting of the film supply roll, and work at the time of maintenance. Can be improved. In addition, according to the present invention, it is possible to prevent damage to the printing of the transfer film before transfer by omitting a mechanism for detecting by contacting the transfer film in order to detect the roll diameter of the film supply roll. .

It is a mimetic diagram showing a transfer molding device provided with a tension control device of an embodiment. It is a mimetic diagram showing the tension control device of an embodiment. It is a schematic diagram which shows the tension control apparatus relevant to this invention. It is a schematic diagram which shows the other structural example of the tension control apparatus relevant to this invention. It is a schematic diagram which shows the other structural example of the tension control apparatus relevant to this invention.

  Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows a schematic diagram of a transfer molding apparatus provided with a tension control device of the present embodiment. In FIG. 2, the schematic diagram of the tension control apparatus of this embodiment is shown.

  As shown in FIG. 1, the transfer molding apparatus includes a tension control device having a film supply device 6 that supplies a transfer film 3 and a film winding device 7 that winds the transfer film 3 supplied from the film supply device 6. I have. In addition, the transfer molding apparatus includes a molding die 8 arranged on the transfer path of the transfer film 3 between the film supply device 6 and the film winding device 7. In addition, the transfer molding apparatus includes a plurality of guide rollers 9 that constitute a transfer path of the transfer film 3.

  As shown in FIG. 2, the tension control device includes a film supply device 6 and a film winding device 7, and a control unit 11 as control means for controlling the film supply device 6 and the film winding device 7. The transfer film 3 has a print of a desired pattern or the like for transferring to a molded product molded in the cavity portion of the molding die 8.

  The film supply device 6 includes a supply roll shaft 13 that supports the film supply roll 12 so as to be rotatable integrally with the film supply roll 12 around which the transfer film 3 is wound, and braking means that brakes the rotation of the supply roll shaft 13. It has the powder clutch 14 and the 1st rotary encoder 15 as a 1st rotation detector which detects the rotation speed of the supply roll axis | shaft 13. As shown in FIG.

  The film supply device 6 winds the transfer film 3 around the film supply roll 12 when the winding operation of the film take-up roll 21 that winds the transfer film 3 supplied from the film supply roll 12 is stopped. A reverse motor 17 is provided for rotating the film supply roll 12 in the direction. A belt 18 is stretched between the rotation shaft of the reverse rotation motor 17 and the supply roll shaft 13, and the reverse rotation motor 17 transmits a driving force to the supply roll shaft 13 via the belt 18 to cause the film supply roll 12 to move. Rotating drive.

  The film take-up device 7 includes a take-up roll shaft 22 that supports the film take-up roll 21 so as to be rotatable integrally with the film take-up roll 21, and a film feed roller 23 that sends the transfer film 3 to the film take-up roll 21. And a servo motor 24 as a driving means for rotating the film feed roller 23.

  As shown in FIG. 1, the film feed roller 23 is disposed on the upstream side in the transport direction of the transfer film 3 with respect to the film take-up roll 21. The servo motor 24 has a second rotary encoder 25 as a second rotation detector that detects the number of rotations of the film feed roller 23.

  Although not shown, a transmission belt (Vancolan belt) is stretched between the rotation shaft of the film feed roller 23 and the take-up roll shaft 22, and the servo motor 24 drives the take-up roll shaft 22 via the transmission belt. And the film take-up roll 21 is rotationally driven.

  The controller 11 supplies the film by controlling the powder clutch 14 according to the roll diameter of the film supply roll 12 based on the signals from the first rotary encoder 15 and the second rotary encoder 25 of the servo motor 24. The tension applied to the transfer film 3 between the roll 12 and the film take-up roll 21 is kept constant.

  Further, the control unit 11 controls the reverse rotation motor 17 based on signals from the first and second rotary encoders 15 and 25 when the winding operation of the film winding roll 21 is stopped. May be configured. This makes it possible to keep constant the tension generated in the transfer film 3 when the winding operation of the film winding roll 21 is stopped according to the roll diameter of the film supply roll 12.

  Note that the rotation detector in the present invention is not limited to the rotary encoder described above, and for example, a resolver or the like may be used. Further, the rotation detector is configured to detect the rotation speed of the supply roll shaft 13 and the film feed roller 23, but an optical element that optically detects the rotation speed of the film supply roll 12 and the film feed roller 23, and the like. In addition, a sensor using electromagnetics may be used.

  Regarding the tension control device of the embodiment configured as described above, an operation for controlling the tension applied to the transfer film 3 to be constant will be described.

  First, when the film take-up roll 21 of the film take-up device 7 rotates, the transfer film 3 is pulled out from the film supply roll 12 of the film supply device 6. The transfer film 3 is conveyed between the film supply roll 12 and the film take-up roll 21 and is positioned at a predetermined position with respect to the molding die 8.

  At this time, although tension is generated in the transfer film, the tension generated in the transfer film 3 changes according to the roll diameter of the film supply roll 12 that decreases as the transfer film 3 is supplied.

  For this reason, the control unit 11 controls the servo motor 24 based on the signal from the second rotary encoder 25 and also controls the powder clutch 14 based on the signals from the first and second rotary encoders 15 and 25, respectively. To control.

  At this time, the control unit 11 calculates a film feed amount L by which the transfer film 3 is fed by the film feed roller 23 based on a signal from the second rotary encoder 25 of the servo motor 24. Further, the control unit 11 calculates the rotation speed N of the film supply roll 12 (supply roll shaft 13) based on the signal from the first rotary encoder 15. Subsequently, the control unit 11 determines the roll diameter (diameter) of the transfer film 3 wound around the film supply roll 12 based on the film feed amount L by the film feed roller 23 and the rotation speed N of the supply roll shaft 13. 2R is calculated.

The roll diameter 2R of the film supply roll 12 is determined from the following relationship.
Film feed amount L = (circumference of film supply roll 12: 2πR) × rotational speed N
Roll diameter 2R = film feed amount L ÷ π ÷ rotational speed N
Specifically, for example, when the film feed amount L as a film unwinding amount is 314 mm and the rotation speed N is half rotation (0.5), the roll diameter of the film supply roll 12 is 2R = L / 3. .14 / N = 314 / 3.14 / 0.5 = 200 mm.

  When the film feed amount L, which is the amount of unwinding of the film at one time, is 314 mm and the rotation speed N is one rotation (1), the roll diameter of the film supply roll 12 is 2R = L / 3.14 / N = 314 / 3.14 / 1 = 100 mm is calculated. Then, the control unit 11 controls the powder clutch 14 according to the calculated roll diameter 2R of the film supply roll 12.

  And the control part 11 controls the rotation speed N of the film supply roll 12 by braking the rotation of the supply roll axis | shaft 13 by the powder clutch 14 according to the roll diameter 2R of the film supply roll 12. FIG.

  In addition, the control part 11 keeps the tension | tensile_strength of the transfer film 3 by controlling so that the braking force by the powder clutch 14 may become small as the roll diameter 2R of the film supply roll 12 becomes small. At this time, the control unit 11 controls the braking force with reference to a table of the relationship between the magnitude of the current applied to the powder clutch 14 and the magnitude of the braking force generated by the powder clutch 14.

  In short, the control unit 11 controls the braking force by the powder clutch 14 as the roll diameter 2R of the film supply roll 12 decreases, and is applied to the transfer film 3 between the film supply roll 12 and the film take-up roll 21. Keep the tension to be constant.

  The film supply device 6 supplies the transfer film 3 in the direction of winding the transfer film 3 onto the film supply roll 12 by the reverse rotation motor 17 when the winding operation of the film winding roll 21 is stopped. The film supply roll 12 is rotated in the direction opposite to the direction. Thereby, when the winding operation of the film winding roll 21 is stopped, the tension of the transfer film 3 positioned with respect to the molding die 8 is suppressed from fluctuating.

  As described above, the tension control device according to the embodiment controls the servo motor 24 based on the signal from the second rotary encoder 25 and outputs the signal from each of the first and second rotary encoders 15 and 25. The control part 11 which controls the powder clutch 14 based on is provided. Thereby, the control unit 11 calculates the roll diameter 2R of the transfer film 3 wound around the film supply roll 12, and controls the rotation speed N of the film supply roll 12 by the control unit 11 according to the roll diameter 2R. Thus, the tension applied to the transfer film 3 between the film supply roll 12 and the film take-up roll 21 can be kept constant.

  Therefore, according to this embodiment, even when the roll diameter 2R of the film supply roll 12 gradually decreases with the supply of the transfer film 3, the gap between the film supply roll 12 and the film take-up roll 21 is reduced. A constant tension can always be applied to the transfer film 3 positioned with respect to the molding die 8 regardless of the change in the roll diameter 2R of the film supply roll 12.

  According to the embodiment, a brake mechanism that contacts and brakes the transfer film 3 or a mechanism that contacts the transfer film 3 to detect the roll diameter 2R of the film supply roll 12, for example, a configuration described in Patent Document 1 It is possible to omit the roll diameter measuring lever 120 and the potentiometer 121 included in the.

  For this reason, in the present embodiment, the roll diameter measuring lever 120 for detecting the roll diameter of the film supply roll, which has been an obstacle to the replacement or mounting of the film supply roll in the configuration described in Patent Document 1, is provided. It becomes possible to omit, and the workability | operativity at the time of replacement | exchange and mounting | wearing of the film supply roll 12 can be improved. In addition, according to the present embodiment, the adjustment work of the roll diameter measuring lever 120 and the potentiometer 121 is not required, so that maintainability can be improved.

  Further, according to the present embodiment, the printing mechanism of the transfer film 3 before transfer is damaged by omitting the mechanism that detects the contact diameter of the transfer roller 3 in order to detect the roll diameter 2R of the film supply roll 12. Can be prevented.

  Further, in the present embodiment, fluctuations in tension generated in the transfer film 3 positioned with respect to the molding die 8 are driven by driving the reverse rotation motor 17 when the rotation of the film take-up roll 21 is stopped. Can be suppressed.

DESCRIPTION OF SYMBOLS 3 Transfer film 6 Film supply apparatus 7 Film winding apparatus 11 Control part 12 Film supply roll 13 Supply roll axis | shaft 14 Powder clutch 15 1st rotary encoder 21 Film winding roll 22 Winding roll axis | shaft 23 Film feed roller 24 Servo motor 25 Second rotary encoder

Claims (3)

A supply roll shaft that supports the film supply roll so as to rotate integrally with a film supply roll on which a transfer film is wound, braking means that brakes the rotation of the supply roll shaft, and the rotational speed of the supply roll shaft. A first rotation detector for detecting, a film supply device comprising:
A take-up roll shaft that supports the film take-up roll so as to rotate integrally with a film take-up roll that takes up the transfer film supplied from the film supply roll, and the transfer film to the film take-up roll A film take-up device comprising a film feed roller for feeding, a driving means for rotating the film feed roller, and a second rotation detector for detecting the number of rotations of the film feed roller;
Control means for controlling the driving means based on a signal from the second rotation detector, and for controlling the braking means based on a signal from each of the first and second rotation detectors; Prepared,
Between the film supply roll and the film take-up roll, a transfer part for transferring a print image of the transfer film to a transfer material is disposed,
The film feed roller is disposed at a position between the transfer portion and the film take-up roll,
The control means calculates the roll diameter of the transfer film wound around the film supply roll, and controls the number of rotations of the film supply roll by the braking means according to the roll diameter. with keeping the tension applied to the transfer film between the roll and the film take-up roll at a constant, when the winding operation of the film winding roll is stopped, the transfer film in the film supply roll A transfer film tension control device that rotates the film supply roll in a winding direction . 2. The transfer film tension control device according to claim 1, wherein the film winding device includes a servo motor including the driving unit and the second rotation detector. 3. The transfer film supplied from the film supply roll is sent to a transfer portion for transferring a print image of the transfer film to a transfer material, and the film is wound on a film take-up roll for winding the transfer film that passes through the transfer portion. The control means calculates the roll diameter of the transfer film wound around the film supply roll based on the film feed amount to which the transfer film is fed by the feed roller and the rotation speed of the film supply roll, and the roll diameter Accordingly, the control means controls the number of rotations of the film supply roll, so that the tension applied to the transfer film between the film supply roll and the film take-up roll is kept constant, and the film winding When the winding operation of the take-up roll is stopped, the roll is transferred to the film supply roll. It controls to rotate the film supply roll in the direction of winding the film, tension control method of the transfer film.

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