JPH06144650A - Image recording device - Google Patents

Abstract

PURPOSE:To correct the attitude of recording paper into the normal state at the time of conveying roll recording paper so as to record images thereon. CONSTITUTION:A recording sheet 100 is conveyed through a conveyor means 9 for conveying the recording sheet 100 from a roll paper tube 4 with the recording sheet wound thereon. The recording sheet fed through this conveyor means 9 is wound with the recording sheet tip fed into a pressure point between the roller 10 and pinch roller 13b of a winding means 13 formed of the roller 10 and the pinch roller 13b in contact with the roller 10, and images are recorded onto the conveyed recording sheet by recording means 1, 6 provided at a carrier path. A control means 60 is provided to stop the winding means 13 at the beginning of winding the recording sheet onto the winding means 13 and to perform the start control of rotation to start winding after the lapse of the specified time from the time of the recording sheet tip reaching the pressure point or after conveying the sepcified quantity of the recording sheet.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention uses an electrostatic recording system to
The present invention relates to a sheet conveying mechanism in an image forming apparatus that directly forms a monochrome image or a color image on a roll of electrostatic recording paper or the like.

[0002]

2. Description of the Related Art Conventionally, in an image forming apparatus such as a color electrostatic plotter which directly forms a color image on a sheet of paper such as an electrostatic recording paper wound in a roll by an electrostatic recording method, the electrostatic recording paper is rolled. Between the roll paper tube wound in a circle and the take-up roller that temporarily winds the tip of the electrostatic recording paper,
The electrostatic recording paper is transported back and forth many times, and black, cyan, magenta, and yellow images are superimposed in the meantime,
Forming a color image.

As the winding means, a paper guide for guiding and conveying the leading edge of the electrostatic recording paper around a winding roller having a surface friction coefficient controlled, which is slightly wider than the width of the electrostatic recording paper. A plurality of pinch rollers for enclosing and winding are arranged symmetrically in the longitudinal direction of the winding roller.

The leading edge of the electrostatic recording paper conveyed to the take-up roller enters the nip point (pressing point) between the take-up roller and the pinch roller in contact therewith while being conveyed while being guided by the paper guide. At this time, since the take-up roller is rotating at a sufficiently high peripheral speed with respect to the electrostatic recording paper being conveyed, the leading edge of the electrostatic recording paper is conveyed while slipping at the same time as entering the nip point. First, it winds around the take-up roller.

When the electrostatic recording paper is completely wound around the take-up roller, the rotation speed of the take-up roller is reduced to the same peripheral speed as the conveying speed of the electrostatic recording paper, and the electrostatic recording is conveyed. Roll the paper in order.

[0006]

When a color image is to be printed by the image forming apparatus having the winding means as described above, the alignment of each color is performed by conveying the paper between the winding roller and the roll paper tube. It depends on the accuracy.

Specifically, when the electrostatic recording paper is reciprocally conveyed between the take-up roller and the roll paper tube, the alignment in the paper feed direction is usually performed by adjusting the timing marks recorded on the electrostatic recording paper. This is performed by reading the position with an image sensor such as a CCD (solid-state image sensor) sensor. That is, images of respective colors are sequentially formed in accordance with the timing mark position.

On the other hand, in the paper width direction, the paper often shifts little by little while being reciprocally conveyed between the winding roller and the roll paper tube. It is considered that the cause of this lateral deviation in the paper width direction is that the winding of the electrostatic recording paper around the take-up roller has the greatest influence.

The method of winding the electrostatic recording paper around the take-up roller largely depends on the parallelism of the take-up roller, the drive roller, the roll paper tube and the shape accuracy of the take-up roller guide. There is a problem in terms of structure and cost to increase the above. Further, since the degree of curling of the electrostatic recording paper and the temperature and humidity at that time also affect the accuracy, there is a limit to the correspondence only with the component accuracy and the assembly accuracy.

Therefore, the object of the present invention is to
In an image forming apparatus that forms an image on a paper surface by repeatedly moving and scanning a roll paper such as a color electrostatic plotter,
An object of the present invention is to provide an image forming apparatus capable of suppressing the lateral deviation in the paper width direction without improving the component accuracy and the assembly accuracy.

[0011]

In order to solve the above problems, the present invention has the following constitution. That is, the recording sheet is conveyed from a roll paper tube around which the recording sheet is wound via a conveying means for conveying the recording sheet, and the recording sheet sent through the conveying means is composed of a roller and a pinch roller in contact with the roller. An image recording apparatus in which the leading end of a recording sheet is sent to the nip point between the roller and the pinch roller of the winding means and wound up, and an image is recorded on the conveyed recording sheet by the recording means provided on the conveying path. At

First, at the initial stage of winding the recording sheet around the winding means, the winding means is stopped, and after the leading edge of the recording sheet reaches the nip point, a predetermined time elapses or a predetermined amount of recording is performed. After the sheet is conveyed, a control means for controlling the start of rotation to start winding is provided.

Secondly, at the beginning of the winding of the recording sheet onto the winding means, the conveying means is stopped after the leading edge of the recording sheet reaches the nip point, and the conveying is restarted after a lapse of a predetermined time. It is configured by providing a control means for controlling.

Thirdly, at the initial stage of winding the recording sheet around the winding means, the winding means is controlled to operate at high speed and high torque for a predetermined time required for the leading edge of the recording sheet to reach the nip point. The control means for controlling to switch between the normal speed operation and the normal torque operation is provided.

[0015]

In the case of the first construction, at the initial stage of winding the recording sheet around the winding means, the winding means is stopped, and after the leading edge of the recording sheet reaches the nip point, a predetermined time or a predetermined amount of the recording sheet is reached. Since the recording sheet is conveyed, the leading edge of the recording sheet is curled around the nip point, and the leading edge of the recording sheet takes a predetermined posture at the nip point. After that, since the winding means starts winding, the recording sheet is wound around the winding means without wrinkles or slack. Therefore, the lateral deviation of the recording sheet is suppressed during the conveyance.

Further, in the case of the second configuration, at the initial stage of winding the recording sheet around the winding means, the conveying means is stopped after the leading edge of the recording sheet reaches the nip point, and the leading edge of the recording sheet is wound during this period. Although the recording sheet is wound up by the winding means, the leading edge of the recording sheet is at the nip point position and is not wound up to the first round, so that the recording sheet is slipped around the winding means. The slip removes wrinkles and slack from the recording sheet. After the elapse of a predetermined time, the conveyance means is controlled to restart conveyance, and therefore the winding means shifts from the slip state to the recording sheet winding state.
As a result, the recording sheet is wound around the winding means without wrinkles or slack. Therefore, the lateral deviation of the recording sheet is suppressed during the conveyance.

Further, in the case of the third construction, at the initial stage of winding the recording sheet around the winding means, the winding means is controlled to operate at high speed and high torque for a predetermined time required for the leading edge of the recording sheet to reach the nip point. During that time, the leading edge of the recording sheet is taken up by the take-up means, but until the leading edge of the recording sheet reaches the take-up state from the nip point position to the first lap, the recording sheet remains wound around the take-up means. Slip. The slip removes wrinkles and slack from the recording sheet. After a lapse of a predetermined time, the winding means is switched to the normal speed and the normal torque operation, so that the winding means shifts from the slipping state to the recording sheet winding state. As a result, the recording sheet is wound around the winding means without wrinkles or slack. Therefore, the lateral deviation of the recording sheet is suppressed during the conveyance.

With the above-mentioned structure, the leading end position of the recording sheet wound around the take-up roller can be made uniform on the left and right regardless of the surrounding environment, the curl of the paper, the shape accuracy of the paper guide, and the like. This makes it possible to suppress the occurrence of lateral deviation in the paper width direction during paper conveyance.

Therefore, according to the present invention, in an image forming apparatus such as a color electrostatic plotter which forms an image on the surface of a roll paper by repeatedly moving and scanning the roll paper, it is possible to further improve the parts accuracy and the assembly accuracy. It is possible to provide a paper transport mechanism capable of suppressing lateral deviation in the paper width direction.

[0020]

Embodiments of the present invention will be described below with reference to the drawings.

(Structure of Device) The present invention is divided into three embodiments depending on the control mode, but since these embodiments use the same structure, the basic structure of the device of the present invention will be described first. FIG. 1 shows an outline of the configuration of an image forming apparatus according to the present invention.

In FIG. 1, 1 is an electrostatic head for forming an electrostatic latent image on an electrostatic recording paper 100, and 2 is this electrostatic head 1.
A pad roller for pressing the electrostatic recording paper 100 onto the electrostatic recording paper 100 to form an electrostatic latent image on the electrostatic recording paper 100 evenly, a static elimination brush 21 for removing unnecessary static electricity on the non-image forming surface of the electrostatic recording paper 100, 3 is an electrostatic recording paper 1 for the electrostatic head 1.
CCD sensor for detecting the position of 00, 4 is electrostatic recording paper 1
00 is a paper tube that is wound in a roll and supplies the electrostatic recording paper 100 to the image forming unit.

Reference numeral 5 is an encoder roller for feeding the electrostatic recording paper 100 in parallel with the surface of the electrostatic head 1 and detecting the conveying speed of the electrostatic recording paper 100 from the number of rotations thereof. Reference numeral 5e is an encoder roller. 5 and electrostatic recording paper 10
0 is sandwiched between the encoder roller 5 and the electrostatic recording paper 100.
This is an encoder pinch roller that prevents slippage between the encoder and the pinch roller.

Reference numeral 6 is in close contact with the electrostatic recording paper 100, and a wet toner, which is a liquid developing solution, acts on the electrostatic recording paper 100 to form an electrostatic latent image formed on the electrostatic recording paper 100. Is a developing head for developing as a toner image.

The developing head 6 is in the shape of a drum, and the developing head portion 6a for black and the developing head portion 6 for cyan are provided on the peripheral surface.
b, a magenta developing head portion 6c, and a yellow developing head portion 6d are sequentially arranged.

These developing head portions 6a to 6d become head portions which are used for development when they come to the upper position by the rotational scanning of the developing head 6, and the head portions which are used for this development correspond to the heads. The developing solution of the color is supplied, and the developing solution can be made to act on the electrostatic recording paper 100. When the developing head 6 is rotated, the developing solution supplied into the head portion used for development is extracted and dried.

Therefore, the developing heads 6a to 6d are sequentially sent to the developing position in the order of arrangement, and the electrostatic recording paper 1 is placed in this order.
00, and a color image is formed on the electrostatic recording paper 100.

Reference numeral 8 denotes a suction roller for determining the attitude of the electrostatic recording paper 100 in the image forming portion together with the encoder roller 5, and sucking unnecessary toner on the electrostatic recording paper 100.
Is a drive roller for driving the electrostatic recording paper 100 to determine the conveying direction and the conveying speed of the electrostatic recording paper 100, 10 is a winding roller for winding and storing the electrostatic recording paper 100 during image formation, and 12 is a drive It is a drive pinch roller that presses the electrostatic recording paper 100 against the roller and transmits the driving force of the drive roller 9 to the electrostatic recording paper 100.

Further, 13 is a winding pinch roller that helps the electrostatic recording paper 100 to wind around the take-up roller 10 by sandwiching and pressing the electrostatic recording paper 100 against the take-up roller 10, and 11 is the electrostatic recording paper 100. Switch the transport route of
At the position of 11a during printing, the take-up roller 10
A gate for feeding the electrostatic recording paper 100 to the cutter unit 50 by feeding the electrostatic recording paper 100 to the cutter unit 50 when the image formation is completed.

Reference numeral 14 denotes a paper path sensor for detecting the existing position of the electrostatic recording paper, which is a drive roller 9 and a drive pinch roller 1.
It is arranged at an appropriate position on the downstream side of the nip point A with respect to 2 and on the upstream side of the winding roller 10.

Reference numeral 15 is a conveyor belt for conveying the electrostatic recording paper 100 set on the suction roller 8 to the nip point A between the drive roller 9 and the drive pinch roller 12, and the construction will be described later in detail. The drive roller 9 which is an electric recording paper conveying means is wound around both ends of the drive roller 9. The conveyor belt 15 is arranged so as to project toward the upstream side of the electrostatic recording paper conveyance path, and the front end side thereof has a length positioned on the suction roller 8. The conveyor belt 15 is arranged in an inverted C shape toward the upstream side, and by this shape,
When the electrostatic recording paper is fed, both ends of the paper surface are pulled outward so that the posture is correct and wrinkles are removed.

Numeral 19 is from the winding section to the cutter unit 50.
A paper guide 18 for guiding the electrostatic recording paper 100 toward the winding guide 18 is a winding paper guide for assisting the winding of the electrostatic recording paper 100 around the winding roller 10.

Reference numeral 20 is a winding sensor for detecting the number of revolutions of the winding roller 10 to detect the winding of the electrostatic recording paper 100 around the winding roller 10, and more specifically, the slit of the slit plate 20a. The passing time interval of is detected by a sensor such as a photo interrupter.

Reference numeral 30 is a winding motor for rotating the winding roller 10, 30a is a motor pulley, 31 is a winding belt for transmitting the rotation of the winding motor 30 to the winding roller 10 via the roller pulley 10a, and 32 is a driving roller. 9 is a paper guide for guiding and conveying the electrostatic recording paper 100 from the nip point A between the drive roller 9 and the driving pinch roller 12 to the take-up roller 10.

The cutter unit 50 cuts the electrostatic recording paper 100 on which an image is formed into a required image forming portion and an unnecessary portion, and cuts the image into a predetermined drawing size. Y cutter unit section 5
1 and an X cutter unit 52. Reference numeral 22 is a paper discharge guide for guiding the paper cut and discharged by the cutter unit 50 to an external paper storage device.

Reference numeral 54 denotes a paper feed roller for controlling the speed and direction in which the electrostatic recording paper 100 conveyed to the cutter unit 50 is conveyed in the cutter unit 50. A paper feed pinch roller that nips and conveys the recording paper 100. The Y cutter unit 51 cuts the electrostatic recording paper 100 in the paper width direction, and the X cutter unit 52 cuts the electrostatic recording paper 100 cut by the Y cutter unit section 51 in the paper conveyance direction. The paper is cut in the same direction as the above and is discharged to the outside of the machine. 53 is the electrostatic recording paper 10 together with the discharge roller 54.
A paper discharge roller that nips and conveys 0. Further, reference numeral 60 denotes a control device, which controls each element of the present system.

FIG. 2 is a detailed view of the take-up pinch roller unit 13 of the image forming apparatus according to the present invention. 13a in the take-up pinch roller unit 13 is a nip point B between the take-up roller 10 and the take-up pinch roller unit 13.
A winding pinch guide that guides and conveys the electrostatic recording paper 100 up to 13b, a winding pinch roller 13b, and a winding shaft 13c that rotatably supports the winding pinch roller unit 13. 13g is a support arm, one end of which is the winding shaft 13
A winding pinch roller 13b is rotatably supported on the other end of the winding pinch roller 13b.

The winding shaft 13c is provided at a fixed position in parallel with the axis of the winding roller 10 and with its axis centered.
Since the winding pinch roller unit 13 is rotatably supported around the winding shaft 13c by the arm 13g, the winding pinch roller 13b rotates the winding shaft 13c relative to the winding roller 10. It can be moved toward and away from the center. The winding pinch roller 13b
Are arranged symmetrically in the longitudinal direction of the take-up roller 10.

Further, 13d is a winding pinch roller 13b.
A spring for applying a pressing force to the spring, 13e is an adjusting knob for controlling the pressing force of the winding pinch roller 13b by changing the span of the spring 13d by rotating the knob portion thereof, and 13f is for rotating the adjusting knob 13e. Spring 1
It is an angle that changes the span of 3d.

That is, the winding shaft 13c is fixed at a fixed position, the winding shaft 13c is formed with a screw hole to be screwed with the screw portion formed on the shaft of the adjustment knob 13e, and the L-shaped angle 13f is formed. Winding shaft 13c by adjusting knob 13e
Attached to.

The winding pinch guide 13a is an arm 13g.
It is fixed to the winding pinch guide 13
a is a spring 13 provided between it and the L-shaped angle 13f
Since it is pressed by d, the pressing force of the take-up pinch roller 13b against the take-up roller 10 can be adjusted by turning the adjusting knob 13e to change the distance between the take-up shaft 13c and the angle 13f.

As described above, the winding pinch roller 13
Five b are arranged symmetrically in the longitudinal direction of the take-up roller 10, and since the configuration of FIG. 2 is a pair of left and right, the take-up pinch roller 13b of five sets is provided with the left and right adjustment knobs. By rotating and adjusting 13e respectively, the pressing force of the winding pinch roller can be adjusted left and right.

Further, as shown in FIG. 3, the drive roller 9 is a roller having a relatively large diameter, and grooves 9a are cut near both ends thereof. At both ends of the drive roller 9, support arms 9b curved in a dogleg shape are provided.
The end side is attached to the shaft of the drive roller 9 and attached, and the pulley 9c is rotatably attached to the other end of the support arm 9b.

The length of the support arm 9b is set so that the pulley 9c is positioned so as to face the suction roller 8. The tips of the support arms 9b attached to both ends of the drive roller 9 are arranged so as to bend inward, and the above-mentioned transport belts 15 are provided between the respective pulleys 9c and the grooves 9a of the drive roller 9. The pair of conveyor belts 15 are stretched around and arranged in an inverted C shape having a narrow leading end when viewed from the downstream side of the electrostatic recording paper conveying path.

With this structure, as the drive roller 9 rotates, the conveyor belt 15 is driven and moved in the same direction at the same speed as the peripheral speed of the drive roller 9 to move the electrostatic recording paper 100 in the forward direction, that is, the paper tube 4. Drive roller 9 in the direction of feeding from
When rotating the conveyor belt 15, the conveyor belt 15 is accompanied by a planetary motion with respect to the drive roller 9, and
Acts so as to contact the suction roller 8, and when the drive roller 9 is rotationally driven in the reverse direction of the electrostatic recording paper 100, that is, in the direction of returning it to the paper tube 4 side, the belt 15 reverses the planetary motion with respect to the drive roller 9. In this direction, the suction roller 8 is separated from the suction roller 8.

The pair of conveyor belts 15 are in the shape of an inverted C when the conveyance path of the electrostatic recording paper 100 is viewed in the forward direction, and are arranged in this shape to contact the electrostatic recording paper 100. As a result, with the movement of the electrostatic recording paper 100, the pair of conveyor belts 15 pull both ends of the paper surface to the outside so as to correct the posture and remove wrinkles. (First Embodiment) Next, the operation of the present apparatus having the above construction will be described. First, the schematic printing operation of the image forming apparatus according to the first embodiment of the present invention will be described with reference to FIG.

In the first embodiment, the take-up roller 10 is stopped at the initial stage, and the take-up roller 10 is stopped.
By feeding the electrostatic recording paper 100 to the recording medium and contacting the nip point B of the winding roller 10 with the leading end of the electrostatic recording paper 100 to form a loop on the leading end side of the electrostatic recording paper 1,
This is a system in which the tip of 00 is nipped by the winding roller 10 in a correct posture without wrinkles and slack, thereby preventing the positional deviation.

The operation will be described in detail. The roll paper tube 4
The electrostatic recording paper 100, which is fed from the electrostatic head 1 and the pad roller 2 and is nipped by the driving roller 9 and the driving pinch roller 12, rotates the roll paper tube 4 in the reverse direction. Drive roller 9 while being given tension
The printing operation is started while being conveyed at a constant speed in the forward direction by the drive pinch roller 12 and the drive pinch roller 12. When the printing operation is started, the electrostatic latent image corresponding to the first color is written by the electrostatic head 1 and is conveyed at a constant speed.

Electrostatic recording paper 100 on which an electrostatic latent image is formed
Comes into contact with the developing head 6 to develop the first color,
After the unnecessary toner is removed by the suction roller 8, the toner is sent through between the paper guide 19 and the paper guide 32, the leading end position is detected by the paper position sensor 14, and the paper is conveyed toward the gate 11. It At this time, since the gate 11 is at the position 11a, the leading end of the electrostatic recording paper 100 is sent to the take-up roller 10.

The leading end of the electrostatic recording paper 100 conveyed to the winding roller 10 has a paper guide 18 and a winding guide 13.
While being guided and conveyed to a, it hits a nip point B between the winding roller 10 and the winding pinch roller 13.

At this time, since the take-up roller 10 is stopped, the leading end of the electrostatic recording paper 100 and the take-up pinch rollers 13b arranged symmetrically in the longitudinal direction of the take-up roller 10 are arranged. Hit the nip point B. Although the winding roller 10 is not rotating, the drive roller 9 is rotating and is transporting the electrostatic recording paper 100 to the winding roller 10, so that a loop is formed near the nip point B.

As described above, the front end of the electrostatic recording paper 100 forms a loop at the nip point B, whereby the electrostatic recording paper 100
The front end positions on the left and right in the paper width direction are aligned at the nip point B. Then, the amount of conveyance of the electrostatic recording paper after the leading edge position is detected by the paper position sensor 14 is counted, and when the electrostatic recording paper 100 is conveyed a sufficient distance to form a loop, the take-up roller 10 moves. Start high speed rotation.

Electrostatic recording paper 10 stopped at nip point B
The leading end of 0 rushes into the nip point B at five locations at the same time and is conveyed at high speed in the forward direction by the winding roller 10 that has started to rotate at high speed, and is wound around the winding roller 10 evenly on the left and right. When the electrostatic recording paper 100 is completely wound around the take-up roller 10, the electrostatic recording paper 100 sent through the drive roller 9 is wound around. 9 and the paper conveyance speed defined by 9. After that, the winding roller 10 rotates at the same peripheral speed as the paper conveying speed, and sequentially winds the conveyed electrostatic recording paper 100.

Since the electrostatic recording paper 100 is a rigid and firm sheet of paper, if the leading end thereof has a cutting surface cut straight at a right angle to the edge, this series of windings is used. By the take-up operation, the take-up roller 10 is evenly wound on the left and right sides.

In addition, there is a pair of inverted C-shaped conveyor belts 15 on the upstream side of the drive roller 9.
As a result of 5 being in contact with the surface of the electrostatic recording paper 100 in the inverted C-shape arrangement, both ends of the paper surface are pulled outward with the movement of the electrostatic recording paper 100 to correct the posture and remove wrinkles. Therefore, in combination with this action, the electrostatic recording paper 100 is conveyed while being wound on the winding roller 10 in the correct position and in the correct posture without wrinkles and slack.

The width of the electrostatic recording paper 100 is as wide as 1 m, and a rotational force in a direction opposite to the feeding direction is applied to the paper tube 4, so that the paper feeding from the paper tube 4 is considerable. Back tension is added. Therefore, if the position and posture on the take-up side are correct, the posture of the electrostatic recording paper 100 is corrected so as to pass through the fixed position over the entire conveying path, and wrinkles and slacks are removed and the electrostatic recording paper 100 is generated. Disappear.

In this way, the electrostatic recording paper 10 is controlled in its attitude.
When the printing of the first color is completed while 0 is conveyed, the developing head 6 and the pad roller 2 are separated from the electrostatic recording paper 100, and then the driving roller 9 is rotated in the direction opposite to that at the time of printing, and electrostatic recording is performed. The paper 100 is rewound on the roll paper tube 4. The rewinding operation is stopped when the leading end of the electrostatic recording paper 100 is rewound to a position just before the nip point A between the drive roller 9 and the drive pinch roller 12.

When the rewinding is completed, the pad roller 2
Is again lowered and brought into contact with the electrostatic recording paper 100, the developing head 6 rotates by 45 °, and the developing head portion for the second color faces and contacts the electrostatic recording paper 100 to prepare for printing the second color. Is completed. Similarly, printing of the second and third colors is performed.

After the printing of the third color is completed, the electrostatic recording paper 10
When 0 is completely rewound on the roll paper tube 4, the gate 11
Is switched to the position of 11b, and the paper path is changed from the direction of the take-up roller 10 to the arrangement direction of the cutter unit 50.

The electrostatic recording paper 100 is sent to the cutter unit 50 while the fourth color image is formed on the electrostatic recording paper 100 as in the printing operation up to the third color. The electrostatic recording paper 100 sent to the cutter unit 50 is cut off by the Y cutter unit 51 at the leading edge of the non-image portion, and then the image portion and the unimaged portion are separated by the Y cutter.
The unit 51 similarly disconnects.

Next, when the unnecessary portions at both ends of the electrostatic recording paper 100 are cut off by the X cutter unit 52 and the size of the image is A2 size or smaller, the X cutter unit 52 is further added.
The sheet is cut into sheets and discharged through the sheet discharge guide 22 to the outside of the machine.

After the image portion is discharged to the outside of the machine, the electrostatic recording paper 100 from which the image portion has been separated is rewound, and when the leading edge comes before point A, the rewinding is stopped and the printing operation is completed. To do. The above operation is realized by the control function of the control device 60, and the flow of the above operation is shown in the flowchart of FIG.

As described above, in the first embodiment, at the initial stage, the take-up roller 10 stops rotating, the electrostatic recording paper 100 is fed to the take-up roller 10 in the stopped state, and the nip point B of the take-up roller 10 is reached. The front end side of the electrostatic recording paper 100 is looped in such a manner that the front end of the electrostatic recording paper 100 is applied to the end of the electrostatic recording paper 100 so that the front end of the electrostatic recording paper 100 is nipped by the take-up roller 10 in a correct posture to prevent wrinkles and wrinkles. This is a method of preventing slack and maintaining a correct posture and preventing misalignment, and it is possible to suppress lateral deviation in the paper width direction without improving component accuracy and assembly accuracy. Next, a control mode as the second embodiment will be described.

(Second Embodiment) A schematic attitude control and printing operation of an image forming apparatus according to a second embodiment of the present invention will be described with reference to FIG.

In the second embodiment, the electrostatic recording paper 100 is taken up by the take-up roller 10, and the end of the electrostatic recording paper 100 of the take-up roller 10 is placed on the take-up roller 10 and the electrostatic recording paper 100 is taken up.
Of the electrostatic recording paper 100 is stopped on the take-up roller 10 by stopping the driving roller 9 for a certain period of time to stop the conveyance of the electrostatic recording paper 100 before the first recording is completed. The winding end is slipped to remove wrinkles and slack, and the posture is corrected to correct the position. The operation will be described below.

As in the case of the first embodiment, the electrostatic recording paper 1
After 00 is formed with an image, it is conveyed to the winding roller 10. The leading end of the electrostatic recording paper 100 conveyed to the winding roller 10 has a paper guide 18 and a winding guide 13.
While being guided and conveyed to a, the roller 10 and the take-up pinch roller 13, which is arranged symmetrically in the longitudinal direction of the take-up roller 10, are provided at five nip points B.

At this time, the take-up roller 10 is rotated with a peripheral speed sufficiently higher than the paper conveying speed and a torque sufficiently large with respect to the winding load of the electrostatic recording paper 100. Therefore, the leading edge of the electrostatic recording paper 100 is transported at high speed while slipping at the moment when it enters the nip point B.

The amount of conveyance of the electrostatic recording paper 100 after detecting the position of the front end of the electrostatic recording paper 100 by the paper position sensor 14 is counted, and the front end of the electrostatic recording paper 100 exceeds point B by 10 mm or more. The rotation of the drive roller 9 is stopped before being sandwiched between the winding roller 10 and the electrostatic recording paper 100.

At this time, the number of rotations of the winding roller 10 hardly drops, so that a sufficient slip amount can be obtained. Therefore, the electrostatic recording paper 100 continues to slip at the nip point B, and during that time, wrinkles and ruffles of the electrostatic recording paper 10 are eliminated and the left and right leading edge positions are aligned.

When the electrostatic recording paper 100 is slipped for a predetermined time, the drive roller 9 starts to rotate again. The leading edge of the electrostatic recording paper 100 starts to be conveyed at high speed while slipping again, and the winding roller 10 is evenly wound on the left and right sides. When the electrostatic recording paper 100 is completely wound around the take-up roller 10, the number of rotations of the take-up roller 10 matches the paper conveyance speed defined by the drive roller 9.

Thereafter, the winding roller 10 rotates at the same peripheral speed as the paper conveying speed, and sequentially winds the conveyed electrostatic recording paper 100. After this, as in the case of the first embodiment, printing is performed, cutting is performed, and the sheet is discharged.

The type of the electrostatic recording paper 100 on which an image is formed (plain paper, tracing paper, synthetic paper, film) is input from an operation panel (not shown), and the electrostatic recording paper 100 is selected according to the type. Then, the pause time of the drive roller 9 is changed and set.

Specifically, plain paper with a high coefficient of friction and weak stiffness, trepe (tracing paper) is 1.2 seconds, and synthetic paper with a low coefficient of friction and strong stiffness is about 0.8 seconds. However, for the temporary stop time of the drive roller 9, the ratio of plain paper, trepe to synthetic paper, and film remains unchanged,
It is also possible to change the set value by inputting from the operation panel. The above operation is realized by the control function of the control device 60, and the flow of the above operation is shown in the flowchart of FIG.

As described above, in the second embodiment, after the leading edge of the recording paper is detected by the paper position sensor 14 which is the detecting means, the recording paper 100 is conveyed by the drive roller 9 which is the conveying means after a predetermined time or a predetermined distance. Of the paper position sensor 1
In step 4, the amount of conveyance of the electrostatic recording paper 100 after detecting the front end position of the electrostatic recording paper 100 is counted,
Before the nip point B of the take-up roller 10 is sandwiched between the take-up roller 10 and the electrostatic recording paper 100, that is, the tip of the electrostatic recording paper 100 is taken up by the take-up roller 1.
Before the winding of one turn to 0, the rotation of the driving roller 9 is stopped, and the recording paper conveyance is stopped, so that the winding roller 10 slips the leading end side of the electrostatic recording paper 100, and The slip state of the electrostatic recording paper at the point B is obtained, the wrinkles and the slack of the electrostatic recording paper 10 are eliminated by this slip so that the left and right leading end positions are aligned, and then the drive roller 9 is rotated. This is to restart and start conveyance and recording.

As described above, by interposing the slip operation, the left and right tip positions in the paper width direction are aligned, so that the lateral deviation in the paper width direction can be suppressed without improving the parts accuracy and the assembly accuracy. Like

In the second embodiment, the leading end of the recording paper is taken up by the take-up roller 10 at the initial stage when the take-up roller 10 starts to be wound.
The position and posture are corrected by slipping on the top to remove wrinkles and slack, but there is a possibility that the preparation time before the start of printing may be long because the recording paper conveyance is stopped. . Another correction example for improving this will be described as a third embodiment.

(Third Embodiment) A schematic printing operation of an image forming apparatus according to a third embodiment of the present invention will be described with reference to FIG.

In the third embodiment, the leading edge of the recording paper is the take-up roller 1.
At the stage of starting winding to 0, the take-up roller 10 is rotated at a higher speed and a higher torque than the recording-paper conveying speed to cause the leading end of the recording paper to slip on the take-up roller 10 and then return to the normal speed and torque. The control is performed so that the front end of the recording paper is wound around the winding roller 10. The operation will be described below.

As in the case of the first embodiment, the electrostatic recording paper 100 is conveyed to the take-up roller 10 after the image is formed. The leading end of the electrostatic recording paper 100 conveyed to the winding roller 10 has a paper guide 18 and a winding guide 1.
While being guided and conveyed to 3a, it rushes into the nip point B between the winding roller 10 and the winding winding pinch roller 13.

At this time, since the take-up roller 10 rotates at a peripheral speed (first speed) sufficiently higher than the paper conveying speed, when the leading end of the electrostatic recording paper 100 enters the nip point B, it slips. While being transported at high speed. At this time, since the torque of the winding motor that rotationally drives the winding roller 10 is also sufficiently large, even after the electrostatic recording paper 100 is nipped at the nip point B, the rotation speed does not decrease and electrostatic recording is performed. Paper 1
00 can be slipped sufficiently.

In the meantime, wrinkles and wrinkles of the electrostatic recording paper 100 are eliminated and the left and right leading edge positions are aligned. The conveyance amount of the electrostatic recording paper 100 after the front end position of the electrostatic recording paper 100 is detected by the paper position sensor 14 is counted, and the front end of the electrostatic recording paper 100 is the take-up roller 10 and the electrostatic recording paper 100.
Just before being sandwiched between the take-up roller and the electrostatic recording paper 100, that is, before the leading edge of the electrostatic recording paper 100 has finished winding around the take-up roller 10 for the first time. Drop to state 2.

As a result, the tip of the electrostatic recording paper 100 slips slightly and then completely winds around the take-up roller 10. When the electrostatic recording paper 100 is completely wound around the take-up roller 10, the number of rotations of the take-up roller 10 matches the paper conveyance speed defined by the drive roller 9.

At this time, the torque of the winding roller 10 is the second torque.
Since it has fallen into the state, it does not affect the drive roller 9. After that, the take-up roller 10 winds the conveyed electrostatic recording paper 100 in order while rotating at the same peripheral speed as the paper conveying speed. After this, printing is performed as in the case of the first embodiment, cut and discharged to the outside of the machine. The above operation is realized by the control function of the control device 60, and the flow of the above operation is shown in the flowchart of FIG.

As described above, in the third embodiment, at the stage of starting to wind the leading end of the recording paper on the take-up roller 10, the take-up roller 10 is rotated at a higher speed and a higher torque than the recording paper conveying speed to wind the leading end of the recording paper. The paper is slipped on the take-up roller 10 and then returned to normal speed and torque so that the leading end of the recording paper is taken up by the take-up roller 10. In this case, the leading edge of the recording paper is slipped on the take-up roller 10, so that the wrinkles and slack of the recording paper are removed and the position and posture are corrected, and a correct state in which lateral misalignment is hard to occur is made. By switching the speed of the above, the preparation time from the completion of the series of operations to the printing operation can be shortened.

As described above, the three examples in which the wrinkles and the slack of the conveyed electrostatic recording paper are eliminated, the correct posture is maintained, and the lateral deviation in the paper width direction can be suppressed without improving the component accuracy and the assembly accuracy. Although the present invention has been described, the present invention is not limited to the above-described embodiments, and can be appropriately modified and implemented within the scope of the invention.

[0086]

As described above in detail, according to the present invention, the leading end of the electrostatic recording paper can be evenly wound around the take-up roller, and the paper conveying mechanism is free from the lateral deviation in the paper width direction. An image forming apparatus having the above can be provided.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view of an image forming apparatus according to the present invention.

FIG. 2 is a detailed view of a winding pinch roller 13 portion of the image forming apparatus according to the present invention.

FIG. 3 is a perspective view showing a configuration of a drive roller mechanism portion of the image forming apparatus according to the present invention.

FIG. 4 is a flowchart showing a flow of operations of the first embodiment of the present invention.

FIG. 5 is a flowchart showing a flow of operations of the second embodiment of the present invention.

FIG. 6 is a flowchart showing a flow of operations of the third embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Electrostatic head 2 ... Pad roller 3 ... CCD sensor 4 ... Paper tube 5 ... Encoder roller 5e ... Encoder pinch roller 6 ... Developing head 8 ... Suction roller 9 ... Driving roller 10 ... Winding roller 11 ... Gate 12 ... Driving pinch Roller 13 ... Take-up pinch roller 14 ... Paper path sensor 15 ... Conveyor belt 18, 19, 32 ... Paper guide 20 ... Take-up sensor 21 ... Eliminating brush 22 ... Paper ejection guide 30 ... Take-up motor 31 ... Take-up belt 50 ... Cutter unit 51 ... Y cutter unit 52 ... X cutter unit 53 ... Paper discharge
Ra 54 ... Paper feeding roller 55 ... Paper feeding pinch roller 60 ... Control device.

Claims (4)

[Claims] 1. A recording sheet is conveyed from a roll paper tube around which the recording sheet is wound via a conveying unit that conveys the recording sheet, and
The recording sheet sent through the conveying means is wound up by feeding the leading end of the recording sheet to the nip point between the roller and the pinch roller of the winding means constituted by a roller and a pinch roller in contact with the roller, and a conveying path. In an image recording apparatus in which an image is recorded on a recording sheet conveyed by a recording means provided on the recording sheet, at the beginning of winding the recording sheet onto the winding section, the winding section is stopped and the leading edge of the recording sheet is stopped. The image recording apparatus is provided with control means for controlling rotation to start winding after a predetermined time has passed or after a predetermined amount of the recording sheet has been conveyed after the sheet reaches the nip point. 2. The recording sheet is conveyed from a roll paper tube around which the recording sheet is wound via a conveying means for conveying the recording sheet, and
The recording sheet sent through the conveying means is wound up by feeding the leading end of the recording sheet to the nip point between the roller and the pinch roller of the winding means constituted by a roller and a pinch roller in contact with the roller, and a conveying path. In an image recording apparatus in which an image is recorded on a conveyed recording sheet by a recording means provided in the recording means, a detecting means for detecting the recording sheet conveyed through the conveying means, and a recording sheet winding means. In the initial stage of winding, the winding means is controlled to stop, and after the detection of the leading edge of the recording sheet by the detecting means, after a predetermined time sufficient for the leading edge of the recording sheet to reach the nip point, the winding is started. An image recording apparatus, comprising: a control unit for controlling the rotation start of the unit. 3. The recording sheet is conveyed from a roll paper tube around which the recording sheet is wound, via a conveying unit that conveys the recording sheet, and
The recording sheet sent through the conveying means is wound up by feeding the leading end of the recording sheet to the nip point between the roller and the pinch roller of the winding means constituted by a roller and a pinch roller in contact with the roller, and a conveying path. In an image recording apparatus configured to record an image on a conveyed recording sheet by the recording means provided in, at the initial stage of winding the recording sheet around the winding means, after the leading edge of the recording sheet reaches the nip point, An image recording apparatus, comprising: a control unit that stops the transport unit and controls the transport to be restarted after a lapse of a predetermined time. 4. The recording sheet is conveyed from a roll paper tube around which the recording sheet is wound via a conveying unit that conveys the recording sheet, and
The recording sheet sent through the conveying means is wound up by feeding the leading end of the recording sheet to the nip point between the roller and the pinch roller of the winding means constituted by a roller and a pinch roller in contact with the roller, and a conveying path. In an image recording apparatus in which an image is recorded on a conveyed recording sheet by the recording means provided on the recording sheet, it is necessary for the leading edge of the recording sheet to reach the nip point at the initial stage of winding the recording sheet around the winding section. An image recording apparatus, comprising: a control unit that controls the winding unit to operate at high speed and high torque for a predetermined time, and then controls to switch to normal speed and normal torque operation.