JP2012246097A - Film moving speed control device, coating device, image forming device, and film moving speed control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a film moving speed control device that can accord the moving speed of a film with the peripheral speed of a conveyance roller.SOLUTION: A film moving speed control device 300 includes: a film 310; an feeding roller 320; a take-up roller 330; a drive motor 340; a conveying roller 350; a contact roller 360; an encoder 370, and a CPU. The contact roller 360 is disposed at least on one of the feeding roller 320 and the take-up roller 330 facing each other, contacts with the film 310 toward the center shaft of the opposing roller, and rotates following the movement of the film 310. The encoder 370 detects the rotation speed of the center shaft 361 of the contact roller 360. The CPU controls the drive of the drive motor 340 so that the conveying speed of the film 310 accords with the peripheral speed of the conveying roller 350 based on the detection result of the encoder 370.

Description

  The present invention relates to a film moving speed control device that controls a driving source in order to keep the moving speed of a film constant, a coating device including the film moving speed control device, an image forming apparatus including the coating device, and a film moving speed. The present invention relates to a film moving speed control method for controlling a driving source so as to be constant.

  A tape take-up device such as a cassette tape winds a tape of a certain length around a feed roller. This tape take-up device has an effect that is superior to a device that rotates only the take-up roller by rotating the take-up roller and the feed roller. The effect is that since both rollers are rotated, the tape can be wound around the take-up roller at high speed and with accurate control of the tape tension.

  It is important how such a tape take-up device can be wound around a take-up roller with reduced damage to the tape.

  Thus, a tape take-up device that can prevent damage to the tape by reducing the number of tension rollers for applying tension to the tape has been disclosed (see, for example, Patent Document 1).

Japanese Patent Laid-Open No. 02-058883

  In a configuration having a take-up roller and a feed-out roller in an apparatus for transporting a film, the film take-up speed becomes higher as the film is taken up if the rotation speed of the take-up roller is made constant. Further, in the apparatus, when the film is thermally transferred to the paper conveyed by the conveyance roller and the coating process is performed, it is necessary to match the conveyance speed of the paper and the moving speed of the film. This problem cannot be solved by Patent Document 1.

  In view of the above problems, an object of the present invention is to provide a film moving speed control device capable of matching the moving speed of a film with the peripheral speed of a transport roller.

  The film movement speed control device of the present invention includes a film, a delivery roller, a take-up roller, a drive source, a transport roller, a contact roller, a speed detection unit, and a control unit.

  The film is coated on the paper. The delivery roller stores the film and delivers the film. The take-up roller takes up the film fed from the feed roller. The drive source drives and rotates the take-up roller. The transport roller is disposed between the feed roller and the take-up roller, and rotates to drive the paper.

  The contact roller is disposed to face at least one of the feed roller and the take-up roller, contacts the film toward the central axis of the opposite roller, and is driven to rotate as the film moves. The speed detector detects the rotational speed of the central axis of the contact roller. The control unit controls driving of the drive source so that the film conveyance speed matches the circumferential speed of the conveyance roller based on the detection result of the speed detection unit.

  In this configuration, the peripheral speed of the transport roller is always constant. Therefore, the film conveyance speed can be made constant by making the film conveyance speed coincide with the peripheral speed of the conveyance roller.

  Further, in this configuration, since the film transport speed and the peripheral speed of the transport roller can be matched, the film transport speed and the paper transport speed can be matched. Therefore, it is possible to set a suitable state for coating the paper.

  Further, in this configuration, since the control of gradually reducing the rotation speed of the take-up roller is performed, the near-end detection of the film stored in the feeding roller can be performed based on the control content.

  The film moving speed control device in the present invention can match the moving speed of the film with the peripheral speed of the conveying roller.

It is a figure which shows the structure of an image forming apparatus provided with the coating apparatus containing the film moving speed control apparatus which concerns on 1st Embodiment of this invention. It is a figure which shows the structure of a film moving speed control apparatus. It is a block diagram of the control system of a film moving speed control apparatus. It is a figure which shows the specific structure of an encoder. It is the figure which looked at the structure of the encoder shown in FIG. 4 from the arrow 374 direction. It is a flowchart which shows the control content of CPU. It is a figure which shows the structure of the film moving speed control apparatus which concerns on 2nd Embodiment of this invention. It is a flowchart which shows the control content of CPU. It is a figure which shows the structure of the moving speed control apparatus which concerns on 3rd Embodiment of this invention.

  Hereinafter, a film movement speed control device according to an embodiment of the present invention will be described in detail with reference to the drawings.

  First, a first embodiment of the present invention will be described.

  FIG. 1 is a diagram illustrating a configuration of an image forming apparatus including a coating apparatus 200 including a film moving speed control apparatus 300 according to the first embodiment of the present invention.

  The image forming apparatus 100 forms a multicolor or single color image on a predetermined sheet according to image data transmitted from the outside. The image forming apparatus 100 includes a document processing device 120, a paper feeding unit 80, an image forming unit 110, and a paper discharge unit 90.

  The document processing device 120 includes a document placement table 121, a document transport device 122, and a document reading unit 123. The document placing table 121 is made of transparent glass and is configured to be able to place a document. The document transport device 122 transports the documents stacked on the document tray one by one. Further, the document conveying device 122 is configured to be rotatable in the direction of the arrow 124, and the document can be placed on the document placing table 121 by opening the document placing table 121. The document reading unit 123 reads a document being transported by the document transport device 122 or a document placed on the document placing table 122.

  The paper feed unit 80 is provided with a paper feed cassette 81, a manual paper feed cassette 82, a pickup roller 83, and a pickup roller 84. The paper feed cassette 81 is a tray for storing regular paper. The manual paper feed cassette 82 is a tray on which irregular paper can be placed. The pickup roller 83 is provided near the end of the paper feed cassette 81, picks up paper one by one from the paper feed cassette 81, and supplies it to the paper transport path 101. Similarly, the pickup roller 84 is provided in the vicinity of the end portion of the manual paper feed cassette 82, picks up paper one by one from the manual paper feed cassette 82, and supplies it to the paper transport path 101.

  The image forming unit 110 includes image forming stations 31, 32, 33, 34, an exposure unit 30, an intermediate transfer belt unit 50, and a fixing unit 70. Each of the image forming stations 31, 32, 33, and 34 is provided with a photosensitive drum 10, a charger 20, a developing device 40, and a cleaner unit 60. Black (K), cyan (C), magenta (M), and magenta (M) are provided. This corresponds to a color image using each color of yellow (Y). In the present embodiment, the image forming station 31 will be described.

  The photoconductor drum 10 is rotated when an image is formed and carries a developer image. Around the photosensitive drum 10, the charger 20, the exposure unit 30, the developing device 40, the intermediate transfer belt unit 50, and the cleaner unit 60 are arranged in this order from the upstream in the rotation direction. The fixing unit 70 is positioned on the most downstream side of the image forming unit 110 on the conveyance path 101.

  The charger 20 is a charging means for uniformly charging the surface of the photosensitive drum 10 to a predetermined potential. In addition to the charger type as shown in FIG. 1, a contact type roller type or brush type charger is used. Sometimes used.

  The exposure unit 30 has a function of forming an electrostatic latent image corresponding to the image data on the surface thereof by exposing the charged photosensitive drum 10 according to the input image data. The exposure unit 30 is configured as a laser scanning unit (LSU) provided with a laser emitting portion, a reflection mirror, and the like. The exposure unit 30 includes a polygon mirror that scans the laser beam and optical elements such as a lens and a mirror that guide the laser beam reflected by the polygon mirror to the photosensitive drum 10. As the exposure unit 30, for example, a method using an EL or LED writing head in which other light emitting elements are arranged in an array can also be adopted.

  The developing device 40 visualizes the electrostatic latent image formed on the photosensitive drum 10 with toner.

  The intermediate transfer belt unit 50 includes an intermediate transfer belt 51, an intermediate transfer belt drive roller 52, an intermediate transfer belt driven roller 53, an intermediate transfer roller 54, and an intermediate transfer belt cleaning unit 55.

  The intermediate transfer belt driving roller 52, the intermediate transfer belt driven roller 53, and the intermediate transfer roller 54 are driven to rotate while the intermediate transfer belt 51 is stretched. Further, the intermediate transfer roller 54 gives a transfer bias for transferring the toner image on the photosensitive drum 10 onto the intermediate transfer belt 51.

  The intermediate transfer belt 51 is provided in contact with the photosensitive drum 10. The toner image formed on the photosensitive drum 10 is transferred to the intermediate transfer belt 51, thereby forming a toner image on the intermediate transfer belt 51. The intermediate transfer belt 51 is formed in an endless shape using, for example, a film having a thickness of about 100 μm to 150 μm.

  Transfer of the toner image from the photosensitive drum 10 to the intermediate transfer belt 51 is performed by an intermediate transfer roller 54 that is in contact with the back side of the intermediate transfer belt 51. A high voltage transfer bias (a high voltage having a polarity (+) opposite to the toner charging polarity (−)) is applied to the intermediate transfer roller 54 in order to transfer the toner image. The intermediate transfer roller 54 is a roller whose base is a metal (for example, stainless steel) shaft having a diameter of 8 mm to 10 mm, and whose surface is covered with a conductive elastic material (for example, EPDM, urethane foam, or the like). With this conductive elastic material, a high voltage can be uniformly applied to the intermediate transfer belt 51. In this embodiment, a roller shape is used as the transfer electrode, but a brush or the like can also be used.

  The electrostatic latent images visualized on the photosensitive drum 10 as described above are stacked on the intermediate transfer belt 51. The image information stacked in this way is transferred onto the sheet by the transfer roller 56 disposed at the contact position between the sheet and the intermediate transfer belt 51 as the intermediate transfer belt 51 rotates.

  At this time, the intermediate transfer belt 51 and the transfer roller 56 are pressed against each other at a predetermined nip, and a voltage for transferring the toner onto the paper is applied to the transfer roller 56 (the polarity opposite to the toner charging polarity (−)). (+) High voltage). Further, in order to obtain the nip constantly, the transfer roller 56 uses either the transfer roller 56 or the intermediate transfer belt drive roller 52 as a hard material (metal or the like) and the other as a soft material such as an elastic roller (elastic rubber roller). Or a foaming resin roller or the like.

  Further, as described above, the toner adhered to the intermediate transfer belt 51 by contacting the photosensitive drum 10 or the toner remaining on the intermediate transfer belt 51 without being transferred onto the sheet by the transfer roller 56 is transferred to the intermediate transfer belt 51. It is set to be removed and collected by the cleaning unit 55. The intermediate transfer belt cleaning unit 55 is provided with, for example, a cleaning blade that contacts the intermediate transfer belt 51 as a cleaning member. The intermediate transfer belt 51 that contacts the cleaning blade is supported by an intermediate transfer belt driven roller 53 from the back side. ing.

  The cleaner unit 60 removes and collects toner remaining on the surface of the photosensitive drum 10 after development and image transfer.

  The fixing unit 70 includes a heating roller 71 and a pressure roller 72, and the heating roller 71 and the pressure roller 72 are configured to rotate with a sheet interposed therebetween. The heating roller 71 is set so as to reach a predetermined fixing temperature by the control unit based on a signal from a temperature detector (not shown). It has a function of fusing, mixing, and pressing the transferred toner image to thermally fix the sheet. An external heating belt 73 for heating the heating roller 71 from the outside is provided.

  The sheet that has passed through the fixing unit 70 reaches the coating apparatus 200 via the sheet discharge roller 92. The coating apparatus 200 includes a film moving speed control device 300 and a thermal head 210 for thermally transferring the film 310 controlled to a predetermined moving speed by the film moving speed control device 300 onto a sheet. The thermal head 210 corresponds to the thermal transfer portion of the present invention. The film moving speed control device 300 will be described later.

  As described above, the coating apparatus 200 performs the coating process on the paper by thermally transferring the film 310 to the paper. The coated paper is glossy and the like, and looks good.

  The paper that has passed through the coating apparatus 200 is discharged to the paper discharge tray 91. The paper discharge tray 91 is a tray for collecting printed sheets.

  When a double-sided printing request is made, when the single-sided printing is completed and the trailing edge of the paper that has passed through the fixing unit 70 is gripped by the paper discharging roller 92 as described above, the paper discharging roller 92 rotates in the reverse direction. The paper is guided to the transport rollers 102 and 103. Then, after printing is performed on the back side of the sheet through the registration roller 104, the sheet is discharged to the discharge tray 91.

  FIG. 2 is a diagram illustrating a configuration of the film moving speed control device 300. FIG. 3 is a block diagram of a control system of the film moving speed control device 300.

  The film movement speed control device 300 includes a film 310, a delivery roller 320, a take-up roller 330, a drive motor 340, a transport roller 350, a contact roller 360, an encoder 370, and a CPU 380. The drive motor 340 corresponds to the drive source of the present invention. The encoder 370 corresponds to the speed detection unit of the present invention. The CPU 380 corresponds to the control unit of the present invention.

  The film 310 is used for coating the paper. The delivery roller 320 stores the film 310 and delivers the film 310. The take-up roller 330 takes up the film 310 fed from the feed roller 320. The drive motor 340 drives and rotates the take-up roller 330. The transport roller 350 is disposed between the feed roller 320 and the take-up roller 330, and rotates to drive the paper.

  The contact roller 360 is disposed to face the take-up roller 330, contacts the film 310 toward the central axis 331 of the take-up roller 330, and rotates following the movement of the film 310. The encoder 370 detects the rotational speed of the central shaft 361 of the contact roller 360. The CPU 380 controls the drive of the drive motor 340 based on the detection result of the encoder 370 so that the moving speed of the film 310 matches the peripheral speed of the transport roller 350.

  The CPU 380 is connected to the ROM 410, the RAM 420, the drive motor 340, and the encoder 370. The CPU 380 reads the control program recorded in the ROM 410 and executes the control program using the RAM 420 as a working area. The CPU 380 receives the detection result from the encoder 370 and transmits a control signal to the driver of the drive motor 340 in order to control the drive of the drive motor 340 based on the detection result.

  The film moving speed control device 300 includes guide rollers 391, 392, guides 393, 394, and a compression spring 395. The guide rollers 391 and 392 have a function of appropriately transporting the film 310 between the thermal head 210 and the transport roller 350 and bringing the surface of the film 310 into contact with the transported paper. The guides 393 and 394 have a function of stably transporting paper passing through the upper surface thereof.

  The compression springs 395 are provided at both axial ends of the contact roller 360, and press the bearings 362 of the contact roller 360 toward the central shaft 331 of the take-up roller 330. As described above, the compression spring 395 presses the contact roller 360 toward the central axis 331 of the take-up roller 330, so that the expansion and contraction of the film 310 can be prevented. Therefore, since the encoder 370 is not affected by the expansion / contraction of the film 310, the moving speed of the film 310 can be accurately detected.

  FIG. 4 is a diagram illustrating a specific configuration of the encoder 370. FIG. 5 is a diagram of the configuration of encoder 370 shown in FIG. 4 as viewed from the direction of arrow 374.

  The encoder 370 includes a wheel 371, a detection sensor 372, and a sensor attachment member 373. The wheel 371 is attached to the center shaft 361 of the contact roller 360 and rotates with the rotation of the center shaft 361. The wheel 371 has a slit 374. The detection sensor 372 includes a transmission type sensor as an example, and detects the slit 374 of the wheel 371. The sensor attachment member 373 is configured integrally with the bearing 362 as an example, and holds the detection sensor 372.

  With this configuration, the encoder 370 is displaced together with the contact roller 360 that is displaced according to a change in the amount of the film 310 wound around the take-up roller 330. Therefore, the encoder 370 can always detect the rotational speed of the central shaft 361 of the contact roller 360, that is, the moving speed of the film 310.

  FIG. 6 is a flowchart showing the control contents of the CPU 380.

  The CPU 380 waits until a drive start command is received (N in S10). The drive start command is, for example, a print command. When the CPU 380 determines that a drive start command has been received (Y in S10), the CPU 380 starts driving the drive motor 340 (S20) and receives a speed detection signal from the encoder 370 (S30).

  The CPU 380 waits until the encoder 370 detects that the rotational speed of the central shaft 361 of the contact roller 360 is equal to or higher than the first predetermined speed (N in S40). The first predetermined speed is the peripheral speed of the transport roller 350 + N mm / sec. When the CPU 380 determines that the encoder 370 detects that the rotational speed of the central shaft 361 of the contact roller 360 is equal to or higher than the first predetermined speed (Y in S40), the CPU 380 reduces the drive speed of the drive motor 340. Control (S50).

  Thereafter, the CPU 380 determines whether or not the drive speed of the drive motor 340 has been reduced by a predetermined value or more (S60). If the CPU 380 determines that the drive speed of the drive motor 340 has not been reduced by more than a predetermined value (N in S60), the process proceeds to S40. On the other hand, if the CPU 380 determines that the drive speed of the drive motor 340 has been reduced by more than a predetermined value (Y in S60), the CPU 380 determines that the film 310 stored in the feed roller 320 is small and notifies the near end (S70). The form control flow is terminated.

  In this configuration, the peripheral speed of the transport roller 350 is always constant. Therefore, the conveyance speed of the film 310 can be made constant by matching the conveyance speed of the film 310 with the peripheral speed of the conveyance roller 350.

  Further, in this configuration, since the conveyance speed of the film 310 and the peripheral speed of the conveyance roller 350 can be matched, the conveyance speed of the film 310 and the conveyance speed of the paper can be matched. Therefore, it is possible to set a suitable state for coating the paper.

  Further, in this configuration, since the control of gradually reducing the rotation speed of the take-up roller 330 is performed, it is possible to detect the near end of the film 310 accommodated in the feed roller 320 based on this control content.

  Next, a second embodiment of the present invention will be described. In each of the embodiments after this embodiment, the description overlapping with that of the first embodiment is omitted.

  FIG. 7 is a diagram showing a configuration of a film moving speed control device 300 according to the second embodiment of the present invention.

  In the present embodiment, the contact roller 360 is disposed to face the feed roller 320. Also in this configuration, the encoder 370 detects the rotational speed of the rotating shaft 361 of the contact roller 360. Therefore, when the film 310 stored in the delivery roller 320 runs out, the rotation of the delivery roller 320 stops, and accordingly, the rotation of the contact roller 360 also stops, so that the film 310 stored in the delivery roller 320 stops. End detection can be performed.

  FIG. 8 is a flowchart showing the control contents of the CPU 380.

  In FIG. 8, the control related to the end detection of the film 310 stored in the delivery roller 320 will be described. After informing the near end of the film 310 (S70), the CPU 380 appropriately executes drive control (deceleration control) of the drive motor 340 (S80). The CPU 380 determines whether or not the rotational speed of the central shaft 361 of the contact roller 360 is equal to or lower than a second predetermined speed (S90). The second predetermined speed is the peripheral speed of the conveying roller 350 -N mm / sec.

  If the CPU 380 determines that the rotational speed of the central shaft 361 of the contact roller 360 is not equal to or lower than the second predetermined speed (N in S90), the process proceeds to S80. On the other hand, when the CPU 380 determines that the rotation speed of the central shaft 361 of the contact roller 360 is equal to or lower than the second predetermined speed (Y in S90), the CPU 380 determines that the film 310 stored in the feed roller 320 has been exhausted and ends the process. Notification is made (S100), and the control flow of this embodiment is terminated.

  In this configuration, when the film 310 stored in the delivery roller 320 runs out, the delivery roller 320 stops rotating, and accordingly the contact roller 360 also stops rotating, so that the end of the film 310 can be detected. it can.

  Next, a third embodiment of the present invention will be described.

  FIG. 9 is a diagram illustrating a configuration of a moving speed control device 300 according to the third embodiment of the present invention.

  In this embodiment, the contact roller 360 </ b> A is disposed to face the feed roller 320, and the contact roller 360 </ b> B is disposed to face the take-up roller 330. Further, the contact rollers 360A and 360B are fixed so as not to move. Further, the feed roller 320 is movable toward the central axis 361A of the contact roller 360A, and the take-up roller 330 is movable toward the central axis 361B of the contact roller 360B.

  In the present embodiment, as an example, the delivery roller 320 can move toward the central shaft 361A of the contact roller 360A by its own weight, and the take-up roller 330 can move by the weight of the contact roller 360B. It can move toward the central axis 361B. As another example, compression springs for pressing the delivery roller 320 toward the central shaft 361A of the contact roller 360A may be provided at both ends in the axial direction of the delivery roller 320. A compression spring for pressing toward the central shaft 361B of the contact roller 360B may be provided at both ends in the axial direction of the take-up roller 330.

  In this configuration, the entrance angle of the film 310 from the delivery roller 320 toward the paper does not change regardless of the number of turns of the film 310 accommodated in the delivery roller 320. Therefore, it is possible to prevent the film 310 from being bent toward the paper.

  In this configuration, the peel angle of the film 310 from the paper toward the take-up roller 330 does not change regardless of the number of turns of the film 310 taken up by the take-up roller 330. Therefore, the peeling accuracy of the film 310 from the paper can be kept uniform.

  Furthermore, as another embodiment, the contact roller 360 may be driven to rotate when the winding roller 330 starts to rotate. With this configuration, when the weight of the film 310 accommodated in the feed roller 320 is large, the film 310 can be stably moved against the starting torque fluctuation due to the weight of the film 310.

  Finally, the description of the above-described embodiment is to be considered in all respects as illustrative and not restrictive. The scope of the present invention is shown not by the above embodiments but by the claims. Furthermore, the scope of the present invention is intended to include all modifications within the meaning and scope equivalent to the scope of the claims.

DESCRIPTION OF SYMBOLS 100-Image forming apparatus 110-Image forming part 200-Coating apparatus 210-Thermal head 300-Film moving speed control apparatus 310-Film 320-Delivery roller 321-Center axis 330-Winding roller 331-Center axis 340-Drive motor 350 -Conveying roller 360-Contact roller 360A-Contact roller 360B-Contact roller 361-Center shaft 361A-Center shaft 361B-Center shaft 370-Encoder 371-Wheel 372-Detection sensor 374-Slit 380-CPU

Claims (7)

A film for coating the paper,
A delivery roller that houses the film and delivers the film;
A take-up roller for winding the film fed from the feed roller;
A drive source for driving and rotating the winding roller;
A transport roller that is disposed between the feed roller and the take-up roller and that rotates to transport the paper;
A contact roller that is disposed opposite to at least one of the feed roller and the take-up roller and contacts the film toward a central axis of the opposite roller, and is driven to rotate as the film moves. Laura,
A speed detector for detecting the rotational speed of the central axis of the contact roller;
A control unit that controls driving of the drive source so as to match the moving speed of the film and the peripheral speed of the transport roller based on the detection result of the speed detection unit;
A film moving speed control device. The abutment roller is disposed opposite the feed roller and is fixed so as not to move;
The film moving speed control device according to claim 1, wherein the feed roller is movable toward a central axis of the contact roller. The film movement speed control device according to claim 1, wherein the speed detection unit is an encoder. The film encoder according to claim 3, wherein the encoder includes a wheel having a slit and a detection sensor for detecting the slit. The film moving speed control device according to any one of claims 1 to 4,
A thermal transfer unit for thermally transferring the film controlled to a predetermined moving speed by the film moving speed control device to paper;
A coating apparatus comprising: An image forming unit;
The coating apparatus according to claim 5, wherein a coating process is performed on the paper that has passed through the image forming unit.
An image forming apparatus comprising: Film take-up control in which a film is fed from a feed roller containing a film for coating the paper, and the fed film is taken up by a take-up roller;
Paper transport control for transporting the paper in a state of being overlapped with the film by driving a transport roller disposed between the feed roller and the take-up roller;
Speed detection control for detecting, during winding of the film, the rotational speed of the central axis of the abutting roller disposed so as to face at least one of the feed roller and the take-up roller and abut against the film When,
A take-up roller control for controlling the drive of the take-up roller so that the moving speed of the film and the peripheral speed of the transport roller coincide with each other based on the rotational speed of the central axis of the contact roller;
A film moving speed control method in which the moving speed of the film and the conveying speed of the paper are always matched by performing the above.

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