JP5354170B2 - Paper feeding device, image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a paper feeder for improving a carrying quality by optimizing back tension, by attaining the long service life by optimizing the sliding quantity of a flange, a relay roller and a rewinding roller. <P>SOLUTION: This paper feeder has the flange 1 having a smaller diameter than the maximum diameter of installable roll paper 2, a flange receiving base 3 for supporting the rotation of the flange 1, the rewinding roller 4 for winding the roll paper 2 on a roll by reversely rotating the flange 1, the relay roller 5 for transmitting the drive of the rewinding roller 4 to the flange 1, a paper feeding roller 6 for imparting a normal rotation to the roll via the roll paper 2 by gripping and sending out the roll paper 2 when progressively sending the roll paper 2, a driving system, a motor and a control system of these for transmitting the driving to paper feeding-rewinding respective rollers. The rotating speed of the flange 1 is made variable when sending out and rewinding the roll paper 2 in response to the residual quantity of the roll paper 2. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a paper feeding device for roll-type sheet media such as roll paper, and an image forming apparatus such as a printer, a plotter, a facsimile machine, and a copying machine equipped with the paper feeding device.

  Conventionally, the roll paper holding method has adopted a spool method or a flange method in order to cope with roll paper of various sizes. That is, the conventional roll paper feeding device can be divided into two types: holding a roll paper by passing a spool through the roll paper, or holding both sides of the roll paper by flanges.

  As a feature of the spool system, it is necessary to pass a long spool through the paper tube of the roll paper, and the user's operability is poor. However, when a rewinding mechanism or the like is provided, by providing a drive transmission mechanism in the spool, Has been advantageous in that it can be driven easily, and has been actively employed when providing a rewinding mechanism.

  In addition, since the flange system is inserted and held in the paper tube from both sides of the roll paper, the user operability is very high. In other words, in the flange system, it is only necessary to set the flanges from both sides of any size of roll paper, so that the setability of the user is improved. However, in order to transmit the drive to the roll during rewinding, the diameter of the flange is made larger than the maximum outer diameter of the roll paper. Therefore, it is necessary to lift the roll paper when setting the flange on the roll paper, and the setting property is deteriorated. In addition, the increase in the diameter of the flange causes a restriction on the layout, and there is a concern about the influence on the machine size.

  In other words, in order to transmit the driving force directly to the roll paper, the flange diameter is made larger than the maximum outer diameter of the roll paper and the driving force is transmitted to the outer diameter of the flange, or the reference in the width direction during paper conveyance is the paper There is only one method of transmitting the driving force to the flange for the end of the flange. If the outer diameter of the flange is increased, the diameter of the flange increases, the machine size increases, and one side is lifted when setting the roll paper. However, there is a drawback that it must be set. In addition, if the reference in the width direction at the time of conveyance is set to the edge of the sheet, there is a fear that problems may occur in the conveyance quality such as wrinkles, twists and skews when conveying a long sheet.

  In addition, as disclosed in Patent Document 1, a roll paper is held by a spool and a one-way gear is used to transmit a drive to the spool only at the time of rewinding to achieve highly accurate conveyance. it can. Further, in Patent Document 2, a flange type and the diameter of the flange is smaller than the maximum outer diameter of the roll paper, and a method of rewinding the roll paper with a receiving roller of the flange is adopted. In this method, when the rewinding speed is constant, it is considered that the slip amount of the receiving roller is increased due to a decrease in the remaining amount of the roll paper, resulting in poor durability.

  Therefore, the present invention provides a rewinding mechanism that satisfies the operability, function, and life of the user. In other words, a flange type setting method in which the flange diameter is smaller than the maximum outer diameter of the roll paper is adopted to compensate for the disadvantages of the above two conventional methods, and a relay roller is sandwiched between the rewind roller and the flange. By transmitting the drive to the flange, a rewinding mechanism having usability is realized.

  Another problem with the conventional system is that the amount of sliding between the relay roller and the flange varies greatly depending on the remaining amount of roll paper, and there is a concern that the service life will be shortened. The purpose is to provide a mechanism that optimizes the sliding amount of the flange, relay roller, and rewinding roller to achieve a long service life, and improves the transport quality by optimizing the back tension. To do.

Among the sheet feeding devices of the present invention, the one according to claim 1 is
A flange with a diameter smaller than the maximum diameter that can be attached to the roll around which the paper is wound,
A flange cradle that supports rotation of the flange;
A rewinding roller for reversely rotating the flange and winding the paper around the roll;
A relay roller for transmitting the drive of the rewinding roller to the flange;
A paper feed roller that grips and feeds the paper during forward feeding of the paper and gives the roll a normal rotation through the paper;
A drive system for transmitting drive to the paper feed roller and the rewind roller, a motor, and a control system thereof,
The control system is
The paper feed amount is variable according to the remaining amount of paper in the roll attached to the flange,
A paper feeding device that can change the rotational speed of the flange during rewinding ,
The outer peripheral surface of the flange that comes into contact with the relay roller and the outer peripheral surface of the relay roller each have the same tapered shape,
While making the relay roller movable along the longitudinal direction of the roll,
A pressurizing mechanism for pressurizing in the moving direction is provided .

Transmission pertaining to claim 2 is the sheet feeding apparatus according to claim 1, wherein the control system, to transmit the driving to the rewinding roller during rewinding of the paper to the roll, the drive during the paper feed-out from the roll It is characterized by not.

According to a third aspect of the present invention, in the paper feeding device of the second aspect , the rewinding roller is provided with an electromagnetic clutch.

According to a fourth aspect of the present invention, in the paper feeding device of the third aspect , a one-way clutch is provided on the rewinding roller.

According to a fifth aspect of the present invention, in the paper feeding device according to the first aspect of the present invention, the driving system includes a detecting unit that detects the remaining amount of the paper of the roll attached to the flange, and transmits a driving force only to the rewinding roller. And the control means controls the number of rotations of the rewinding roller in accordance with the remaining amount of paper on the roll detected by the detection means.

According to a sixth aspect of the present invention, in the paper feeding device according to the fifth aspect , the detection unit detects a paper conveyance speed of the roll.

According to a seventh aspect of the present invention, in the paper feeding device of the sixth aspect , the detection means arranges a driven roller facing the roll, and reads the number of rotations of the driven roller to read the remaining amount of paper on the roll. It is the thing which detects this.

According to an eighth aspect of the present invention, in the paper feeding device according to the fifth aspect , the detecting unit detects an outer diameter of the sheet of the roll.

According to a ninth aspect of the present invention, in the paper feeding device according to the eighth aspect , the detecting means arranges a driven roller so as to face the roll, and the position of the driven roller with respect to the roll is set to the outside of the sheet of the roll. Displaceable according to the diameter, and the detecting means detects the amount of displacement of the driven roller.

The image forming apparatus according to claim 1 0, characterized by comprising a sheet feeding apparatus according to any one of claims 1 to 9.

  According to the present invention, by changing the rewinding speed in accordance with the remaining amount of the roller, the difference between the rewinding speed and the speed of the paper feed roller does not become too large, and the amount of sliding can be minimized and the life is extended. Further, the back tension between the paper feed roller and the roll paper at the time of feeding and rewinding can be optimized, and it becomes possible to obtain a predetermined feeding amount and rewinding amount.

Overview of an inkjet printer utilizing the present invention Enlarged side view of the paper feeder Enlarged plan view of the paper feeder Enlarged plan view of the paper feeder when the remaining amount of roll paper is reduced and the weight is reduced Enlarged side view of the paper feeder showing the arrangement of speed detection rollers An enlarged side view of the paper feeding device showing a state in which the speed detection roller always abuts against the roll paper even when the remaining amount of roll paper decreases. Enlarged side view of a paper feeder that has idler rollers placed against the outer shape of the roll paper 7 is an enlarged side view of the state even when the remaining amount of roll paper decreases in the paper feeder of FIG.

  The best mode for carrying out the present invention will be described below with reference to the embodiments shown in the drawings. The present invention is not limited to the illustrated image forming apparatus, and can be applied to various apparatuses that perform image formation.

  When roll paper is fed and rewound at a constant speed, the roll paper remaining amount decreases and the roll diameter must be set to the minimum when the roll diameter is minimized. When the diameter of the roll paper is large, the rewinding speed becomes faster than the speed of the paper feeding roller, and there is a concern about wear due to slipping. Therefore, the paper feeding device of the present invention is larger than the maximum roll paper diameter that can be attached. A small-diameter flange, a flange cradle that supports the rotation of the flange, a rewinding roller that reversely rotates the flange to wind the paper around the roll, a relay roller that transmits the driving of the rewinding roller to the flange, and grips the paper during progressive paper feeding And a drive system and a motor for transmitting the drive to each of the feed roller, the feed roller, the rewind roller, and the motor It includes a control system, in accordance with the remaining amount of the roll paper, feed paper, the rotational speed of the flange during rewinding variable.

  Then, by changing the rewinding speed according to the remaining amount of the roller, the difference between the rewinding speed and the speed of the paper feed roller does not become too large, the amount of sliding can be minimized, and the life is extended. Further, the back tension between the paper feed roller and the roll paper at the time of feeding and rewinding can be optimized, and it becomes possible to obtain a predetermined feeding amount and rewinding amount.

  Also, the outer peripheral surface of the flange that contacts the relay roller has a tapered shape, and the relay roller has the same tapered shape, so that the relay roller can move freely in the longitudinal direction of the roll and pressurize in that direction. By providing a pressure mechanism, the contact position between the flange and the relay roller changes depending on the weight of the roll paper, so that when the weight is heavy and the roll paper has a large outer shape, the outer diameter of the relay roller is small. When the flange contacts and the rotation speed decreases, the remaining amount decreases and the weight of the roll paper decreases, the rotation speed increases due to contact with the flange at the part where the outer diameter of the relay roller is large. Becomes constant, the amount of sliding can be reduced, and the life is extended.

  When it is necessary to obtain a predetermined amount of rewinding, the roll paper rewinding / feeding speed is 5 to 30% faster than the speed of the paper feed roller regardless of the remaining amount of roll paper. In addition, by setting the taper shape of the relay roller and the flange, the rewind speed of the roll paper is faster than the rewind speed of the paper feed roller, so that an appropriate back tension can be obtained, and the rewind amount is Appropriate value.

  If the roll paper speed is set to be faster than that of the paper feed roller, a slack is generated between the paper feed roller and the roll paper during feeding, and an appropriate back tension cannot be applied. By transmitting the drive to the rewinding roller and not transmitting the drive when the roll paper is sent out, it is possible to obtain an appropriate back tension by sending the roll paper only with the paper feed roller when the roll paper is sent out.

  In this case, an electromagnetic clutch may be provided on the rewinding roller. When rewinding, the electromagnetic clutch is turned on to transmit the drive, and when sending out, the electromagnetic clutch is turned off to prevent the slack between the paper feed roller and the roll paper.

  Further, a one-way clutch may be provided on the rewinding roller. The one-way clutch is arranged to transmit the drive only in the rewinding direction.

  A detection unit that detects the remaining amount of paper on the roll may be provided, and a drive system that transmits a driving force only to the rewind roller may be provided to control the number of rotations of the rewind roller according to the detected remaining amount of the roll. By detecting the remaining amount of roll paper, it is possible to derive an optimum flange rotation speed. In addition, by transmitting the driving force only to the rewinding roller, the amount of rotation of the rewinding roller can be controlled according to the optimum rotation speed of the flange. The detection unit may detect the conveyance speed of the roll paper.

  In addition, the detection roller may be disposed so that the detection unit faces the roll, and the remaining amount of the roll may be detected by reading the number of rotations of the driven roller, and the detection unit detects the outer diameter of the roll paper. It is also good.

  Further, the detecting means may be arranged such that a driven roller is disposed so as to face the roll, and the driven roller can be displaced according to the outer diameter of the roll paper, and the amount of the displacement can be detected.

  FIG. 1 is an overall view of an ink jet printer using the present invention. The strike value is provided with three roll paper feeders, and two flanges 1 are set on both sides of the paper tube of each roll paper 2. The outer shape of the flange 1 is smaller than the maximum outer shape of the roll paper. The roll paper 2 on which the flange 1 is set is set on a flange cradle 3 and is conveyed from a paper feed roller 6 that can be driven by a drive motor 7 to a paper tension applying means. Further, the sheet conveyed between the downstream registration roller 13 and the registration pressure roller 14 is conveyed onto a platen plate on the chamber 18. Since a negative pressure is formed in the chamber by the suction fan 19 disposed at the lower part of the chamber 18 and a plurality of holes are provided on the platen plate, the sheet is sucked onto the platen plate and the flatness of the sheet is increased. Maintained. A carriage 16 on which a head 15 for ejecting ink is mounted is disposed on the platen plate. The carriage 16 reciprocates in the width direction of the paper along the main scanning stay 17 so that the ink is placed on the platen plate. An image is formed on the paper by discharging toward the paper. Each time the carriage 16 moves corresponding to the width of the head, the paper is fed by a predetermined length from the registration roller 13 and when the image formation is completed, the cutter 20 cuts the paper to a predetermined length and reverses it. The paper is conveyed along the paper guide 21 and discharged to the paper discharge tray 22.

  An enlarged view of the sheet feeding device is shown in FIG. A roll cradle (not shown) includes the relay roller 5 and the rear roller 24, and is set on the roll cradle with flanges fitted on both sides of the paper tube of the roll paper 2. The flanges 1 on both sides of the roll paper 2 are set smaller than the maximum outer diameter of the roll paper 2, and the set roll paper 2 is supported by contacting the relay roller 5 and the rear roller 24 with the outer diameter of the flange 1. It has been.

  The paper fed out from the roll paper 2 is conveyed to the upper printing unit by the paper feed roller 6 that is the exit of the paper feed device and its opposing roller. In order to obtain an appropriate amount of sag of the roll paper 2 being conveyed, when the roll paper 2 is rewound, the rewinding roller 4 in contact with the lower side of the relay roller 5 is driven to rotate the relay roller 5. Thus, the paper can be taken up by turning the flange 2. Drive is transmitted from the drive motor 7 to the rewind roller 4 and the paper feed roller 6 via the timing belt.

As shown in FIG. 3, the relay roller 5 and the flange 2 are tapered so that the relay roller 5 and the flange 2 are in contact with each other at the tapered portion. The relay roller 5 moves freely in the longitudinal direction of the roll paper 2, and a spring 26 is provided so as to always move inward. Contact is made at a portion where the weight of the roll paper 2 and the pressing force of the spring 26 are balanced. As shown in FIG. 3, when the remaining amount of roll paper is large and heavy, the narrow portion of the relay roller 5 is in contact with the flange 2. Therefore, the speed transmitted to the relay roller 5 always and reportedly has a constant angular velocity omega ₁ and the contact portion of the relay roller to the flange 2 is Vf = R2ω _1, and the flange 2 and the roll paper 1 angular velocity omega ₂ = speed Vf / R1, and the roll paper 2 is actually rewound becomes Vr = R2 · R3 / R1 × ω 1.

  FIG. 4 shows a case where the remaining amount of the roll paper 2 is reduced and the weight is reduced. In this case, since the remaining amount of the roll paper 2 is reduced and the weight is lightened, the relay roller 5 is moved inward by the pressure applied by the spring, and at the position where the weight of the roll paper 2 is balanced. Therefore, similarly to the above, the speed at which the roll paper 2 is rewound by the driving force transmitted from the relay roller 5 is Vr = R4 · R5 / R1 × ω1.

Since the values of R3 and R5 are determined depending on the type of roll paper to be used, even when the roll paper 2 changes from the maximum outer diameter to the minimum outer diameter , the rewinding speed is always 5 to 5 higher than the speed of the paper feed roller. The taper shape (R2 and R4) of the relay roller 5 and the flange 2 and the spring constant of the spring 26 are set so as to be 30% faster.

  Further, a one-way clutch 27 is connected to the rewinding roller 4 so that the driving force from the driving motor 7 is cut off when rotating in the paper feeding direction and transmitted when rotating in the rewinding direction. By doing so, it is possible to obtain an optimum back tension at the time of paper rewinding, and it is possible to improve the rewinding accuracy. Further, there is no slack between the paper feed roller 6 and the roll paper 2 when the paper is fed, and an appropriate back tension can be obtained even when the paper is fed.

  With the configuration described above, the difference in speed from the rewinding speed of the paper feed roller 6 is within 30% regardless of the remaining amount of roll paper during rewinding. It is possible to reduce the wear of various rollers and achieve a long life.

  In the configuration of the first embodiment, an effect equivalent to that of the first embodiment can be obtained by using an electromagnetic clutch instead of the one-way clutch, and controlling the electromagnetic clutch to be turned off when the paper is fed and turned on when the paper is rewound.

  As shown in FIG. 5, the speed detection roller 28 is disposed so as to abut against the outer shape of the roll paper 2. The speed detection roller 28 is rotated in accordance with the rotation of the roll paper 2, and the rotation is transmitted to the encoder 29 by the timing belt, and the rotation speed of the encoder 29 is read by the sensor 30. The speed detection roller 28 can move freely around the encoder 29 and has a mechanism that applies a force so as to always abut against the outer shape of the roll paper 2. Therefore, as shown in FIG. 6, even if the remaining amount of the roll paper 2 decreases and the outer diameter becomes small, the mechanism always follows the speed detection roller 28 against the roll paper 2.

  The apparatus of this embodiment is equipped with a rewinding motor 31 and transmits the driving of the rewinding roller 31 to the rewinding roller 4 alone by a timing belt. The speed of the roll paper 2 read by the speed detection roller 28 is fed back, and the rewinding motor 31 is set so that the speed of the rewinding roller 4 is slower than the speed of the paper feeding roller 6 at the time of feeding, and faster at the time of rewinding. I have control.

  With the above configuration, the speed of the paper feed roller 6 and the roll paper 2 can be suppressed to a certain difference regardless of the remaining amount of the roll paper 2 at the time of rewinding and feeding, and the slip amount can be minimized. Appropriate back tension can be obtained.

  As shown in FIG. 7, the idler roller 32 is disposed so as to abut against the outer shape of the roll paper 2. The idler roller 32 is attached to the tip of the link 33 and is adapted to be rotated according to the rotation of the roll paper 2. The link 33 can move freely, and an encoder 34 is arranged at the center of rotation so that the encoder 34 can rotate in synchronization with the link 33. A spring 36 is attached to the rear end of the link 33, and a force is applied to the link 33 so that the idler roller 32 always abuts against the roll paper 2.

  When the remaining amount of the roll paper 2 decreases, the state becomes as shown in FIG. Since force is applied to the link 33 by the spring 36, the link 33 rotates even when the outer diameter of the roll paper 2 is reduced, and the idler roller 32 moves following the outer shape. At this time, the encoder 34 at the center of rotation changes by the same angle as the rotation angle of the link, so the change amount is read by the sensor 35.

  Since the rewinding motor 31 transmits the drive to the rewinding roller 4 via the gear, the outer diameter of the roll paper 2 is calculated from the variation amount read from the encoder 34 as described above, and the result is fed back. To optimize the amount of rotation of the rewinding roller. Similar to the third embodiment, setting the speed of the rewinding roller 4 to be faster at the time of rewinding and slower at the time of sending out than the speed of the paper feed roller 6 provides the same effects as in the third embodiment. .

1: Flange 2: Roll paper 3: Flange cradle 4: Rewind roller 5: Relay roller 6: Paper feed roller 7: Drive motor 13: Registration roller 14: Registration pressure roller 15: Head 16: Carriage 17: Main scanning Stay 18: Chamber 19: Suction fan 20: Cutter 21: Reversing paper guide 22: Paper discharge tray 24: Rear roller 26: Spring 27: One-way clutch 28: Speed detection roller 29: Encoder 30: Sensor 31: Rewinding motor 32: Idler Roller 33: Link 34: Encoder 35: Sensor 36: Spring

JP 2006-248863 A JP 2003-276264 A

Claims (10)

A flange with a diameter smaller than the maximum diameter that can be attached to the roll around which the paper is wound,
A flange cradle that supports rotation of the flange;
A rewinding roller for reversely rotating the flange and winding the paper around the roll;
A relay roller for transmitting the drive of the rewinding roller to the flange;
A paper feed roller that grips and feeds the paper during forward feeding of the paper and gives the roll a normal rotation through the paper;
A drive system for transmitting drive to the paper feed roller and the rewind roller, a motor, and a control system thereof,
The control system is
The paper feed amount is variable according to the remaining amount of paper in the roll attached to the flange,
A paper feeding device that can change the rotational speed of the flange during rewinding ,
The outer peripheral surface of the flange that comes into contact with the relay roller and the outer peripheral surface of the relay roller each have the same tapered shape,
While making the relay roller movable along the longitudinal direction of the roll,
A paper feeding device comprising a pressurizing mechanism for pressurizing in the moving direction . The paper feeding device according to claim 1.
The control system is
When the paper is rewound onto the roll, the drive is transmitted to the rewind roller ,
Sheet feeding apparatus according to claim <br/> not to transmit the driving before the time the paper feed-out from Km Lumpur. The paper feeding device according to claim 2.
A sheet feeding device comprising an electromagnetic clutch provided on the rewinding roller . The paper feeding device according to claim 2 .
Sheet feeding apparatus according to claim formed by providing a one-way clutch <br/> that the roller return-out before Kimaki. The paper feeding device according to claim 1 .
Comprising detecting means for detecting the remaining amount of paper of the roll attached to the flange;
Provided with a drive system that transmits drive force only to the rewinding roller ,
The control system is
The sheet feeding device characterized in that the number of rotations of the rewinding roller is controlled in accordance with the remaining amount of paper on the roll detected by the detecting means . The paper feeding device according to claim 5 .
It said sensing means, sheet feeding apparatus according to claim der Rukoto which detects the conveying speed of the sheet of the roll. The paper feeding device according to claim 6 .
A sheet feeder before dangerous knowledge means the driven roller and disposed opposite to said rolls, characterized in der Rukoto those for detecting the remaining amount of sheets of the roll by reading the rotational speed of the driven roller . The paper feeding device according to claim 5 .
The paper feeding device, wherein the detecting means detects an outer diameter of the paper of the roll. The paper feeding device according to claim 8.
Said detecting means, the driven roller and disposed opposite to the roll,
The position of the driven roller relative to the roll is freely displaceable according to the outer diameter of the roll paper ,
The sheet feeding device, wherein the detecting means detects a displacement amount of the driven roller . An image forming apparatus comprising the paper feeding device according to claim 1 .