JPS63218461A - Device for removing curling of sheet-like material - Google Patents

Abstract

PURPOSE:To make it possible to always obtain a constant effect of removing a curling of a sheet-like material by providing a first conveying member, a second conveying member on the downstream of the first conveying member and a delay means for transmitting a variation in the rotational speed of the first conveying member to a second conveying member after delay by a predeter mined time. CONSTITUTION:When a recording sheet 1 is slackened between a first conveying member (first roller) 7 and a second conveying member (second roller) 8, a curling of the sheet 1 can be removed. Further, when the rotational speed of the first roller 7 varies, the rotational speed of the second roller 8 follows the variation after delay by a predetermined time. Accordingly, when the rota tional speeds of the rollers 7, 8 vary so that the conveying speed of the sheet 1 becomes high, the amount of slack of the sheet 1 increases. On the contrary when the conveying speed becomes low, the amount of slack decreases. Thereby, it is possible to obtain a constant effect of removing a curling of the sheet irrespective of variations in the conveying speed.

Description

DETAILED DESCRIPTION OF THE INVENTION <Field of Industrial Application> The present invention relates to an apparatus for removing wrinkles from rolled sheet material used in copying machines, facsimile machines, printers, and the like.

<Prior Art> Conventionally, a roll-shaped sheet material has been used as a recording sheet in a thermal recording device, etc., but this recording sheet is wound around a roll shaft and is therefore curled.

Therefore, some of the above-mentioned recording apparatuses are provided with a curl removal mechanism in the discharge section of the recording sheet. In this configuration, as shown in FIG. 5, discharge rollers are provided on the upstream and downstream sides of the sheet conveyance path, and the leading edge of the recording sheet conveyed by the upstream roller 12a hits the outer periphery of the downstream roller 12b, as shown in FIG. The downstream roller 12b is stopped until it has some slack in the direction opposite to the winding direction, or is rotated at a peripheral speed slower than the upstream roller 12a. Thereafter, the upstream roller 12a and the downstream roller 12b are rotated at the same speed so that the recording sheet 1 is maintained with a certain amount of slack, and the recording sheet 1 is discharged.

In the above manner, the recording sheet 1 is transferred to the upstream roller 12a.
When passing between the rollers 12b and 12b on the downstream side, there is a sudden slack in the direction opposite to the direction of the curl, so that the curl is removed.

<Problems to be Solved by the Invention> In the above configuration, the effect of removing wrinkles in recording sorting is as follows:
The longer the slack time is, the larger the slack time is, and conversely, the shorter the slack time is, the smaller the slack time is.

However, the time it takes the recording sheet 1 to pass between the upstream roller 12a and the downstream roller 12b varies greatly depending on the recording speed. That is, when the recording speed is high, the time for the recording sheet 1 to pass between the rollers 12a and 12b becomes short, and conversely, when the recording speed is low, the time becomes long.

Therefore, the curl removal effect varies depending on the recording speed, making it impossible to always obtain a constant effect, which has been a problem.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to provide a sheet material curl removal device that can always obtain a constant curl removal effect even if the recording speed changes in a recording device or the like. It is in.

<Means for Solving the Problems> The means of the present invention for solving the problems described above includes a first conveyance member that conveys a rolled sheet material, and a downstream side of the first conveyance member in the sheet material conveyance direction. a second conveying member that changes its rotational speed in accordance with a change in the rotational speed of the first conveying member; The present invention is characterized in that it is provided with delay means for transmitting the information.

Effects> According to the above means, when the sheet material is slackened between the first conveying member and the second conveying member, curling of the sheet material is removed. Further, when the rotational speed of the first conveyance member changes, the rotational speed of the second conveyance member follows it by opening for a certain period of time. Therefore, when the rotational speed of the conveyance member changes and the conveyance speed of the sheet material increases, the amount of slack increases, and conversely, when the conveyance speed decreases, the amount of slack decreases.

Therefore, a constant curl removal effect can always be obtained regardless of changes in conveyance speed.

<Example> Next, an example in which the above means is applied to a thermal recording device will be described.

FIG. 1 is a schematic explanatory diagram of a heat-sensitive recording apparatus having a curl removing device, and FIG. 2 is an enlarged view of the +i section of the curl removing device. In the figure, reference numeral 1 denotes a roll-shaped recording sheet wound around a roll shaft 2, which is stored in a roll holder 3. This recording sheet 1 is a heat-sensitive sheet that develops color when heated, and is conveyed in the direction of arrow B by a platen roller 4 that rotates in the direction of arrow A according to the recording speed, and in synchronization with the conveyance, a line that generates heat according to an image signal. An image is recorded by the recording head 5 of the mold. Further, the sheet 1 on which the image has been recorded is cut by an automatic cutter 6 from the rear end of the image, and is discharged from the apparatus by a discharge roller.

The discharge roller also serves as a mechanism for removing wrinkles in the recording sheet 1. To explain the configuration in detail, a first conveying roller pair (hereinafter referred to as "first roller roller") 7 is provided downstream of the cutter 6 in the conveying direction of the recording sheet 1, and a pair of first conveying rollers 7 is provided downstream of the first roller 7 in the sheet conveying direction. A second transport roller pair (hereinafter referred to as "r second roller") 8 is provided at .

Further, a sheet guide 9 is attached between the first roller 7 and the second roller 8, which is warped in the opposite direction to the curl of the rolled recording sheet 1.

The first roller 7 and the second roller 8 are driven and controlled by a control system as shown in FIG. Speed changes. Further, the second roller 8 rotates at the same circumferential speed as the first roller 7 and follows the speed change of the roller rough, but the following is configured to be delayed for a certain period of time.

To explain the delay operation in detail, the recording sheet 1 on which an image has been recorded is conveyed by the first roller 7 that rotates at the same speed v1 as the platen roller 4.

At this time, the second roller 8 is in a stopped state, and the recording sheet 1 whose leading edge has hit the second roller 8 is guided by the sheet guide 9 and is sharply bent in the opposite direction to the curl. The amount of slack at this time is in the state a in FIG. 2 (initial slack Ia). Since only the first roller 7 rotates for a certain period of time from this state, the amount of slack shifts to state b.

After the time t1 has elapsed, the second roller 8 follows the first roller rough and rotates at a speed vl. Therefore, recording speed ■1
When is constant, the slack ■ remains constant at b and is transported.

Next, when the rotational speed of the platen roller 4 accelerates, that is, the recording speed accelerates to V t (V l < V t ), the first roller 7 rotates at a speed of 2, but the second roller 8 rotates at a constant speed. It rotates at speed ■1 only for the time delay. Therefore, the amount of slack increases from state b to state C in FIG. After a period of time has elapsed, the second roller 8 follows the first roller 7 and rotates at a speed of ■2, so that the recording speed increases to
2, the amount of slack remains constant at C in FIG. 2 and is transported.

Further, when the recording speed is decelerated from ■2 to ■1, the first roller 7 rotates at the speed ■1, but the second roller 8 is delayed by a certain amount of time and changes from the speed ■2 to ■.

to slow down. Therefore, during the delay, the amount of slack in the recording sheet 1 shifts from state C to state b in FIG. 2, and the recording sheet 1 is conveyed in this state.

As described above, when the recording speed increases, the amount of slack in the recording sheet increases, and when the recording speed decreases, the amount of slack decreases.

The amount of slack in the recording sheet 1 can be easily set by adjusting the recording speed V, the initial slack amount a, and the delay time L1.

The optimal amount of slack to remove curling curls in recording sheet 1 varies depending on the material of recording sheet 1 and the degree of curling, so when setting recording sheet 1, set the optimum slack amount for that sheet 1. I'll keep it.

Next, recording is performed and a third step is performed to perform the delay operation.
To explain the control system in the figure, 10 is a control unit that controls the entire recording apparatus, and this control unit 10 includes a ROM 10a that stores control programs, etc., and a ROM 10a that temporarily stores processing data such as internal flags. It has RAM10b and R.A.
Buffer 1.M10b stores a timer counter value, which will be described later. Oc is configured. Furthermore, the R.A.
M10b includes a timer 10 (hereinafter referred to as "first timer 1") for measuring the recording speed and the speed of the first roller 7.
d, and a timer 10e (hereinafter referred to as "second timer j") for delay-controlling the drive of the second roller 8.

That is, the first roller 7 measured by the first timer 10d
(or the platen roller 4) is stored in the buffer 10c, and the second timer 10e is operated based on the data in the buffer 10C.
e, the drive of the second roller 8 is controlled with a certain time delay.

The control unit IO controls the drive of the recording head 5 via the driver 11a, and the drive control of the platen roller motor 4a, cutter 6, first roller and second roller motors 7a and 8a is performed by the respective drivers. 1
1b, llc, lid, and lie.

Next, the operation of recording and ejecting a recording sheet by the first roller 7 and the second roller 8 by the control system having the above configuration will be described with reference to the flowchart of FIG. 4.

First, in step S1, the following initialization is performed. That is, (2) a value for counting the initial slack amount a used in step S5 is set. (2) Turn off the first flag used in step S8.

(2) The out buffer pointer used in step 510 is placed at the beginning of the buffer 10c, and a certain delay time t is set at the beginning of the buffer. ■Step 313
The in-buffer pointer used in is set to the beginning of the buffer 10c +1.

Next, in step S2, it is determined whether or not the recorded data is full (FULL), and after waiting until the recorded data is full, step S2 is performed.
Proceed to step 3. Then, the recording head 5 performs a predetermined recording, the platen roller 4 and the first roller 7 advance the recording sheet 1 by one line, and the first timer 10d is activated (step S3.34).

Here, the activation of the first timer 106 means the first timer 1
This refers to the operation of initializing 0d and counting again from the beginning. Next, step S5. In S6, the leading edge of the recording sheet 1 reaches the second roller 8 from the first roller 7, and is conveyed until the amount of slack reaches the initial setting amount a.

Next, in step 7'S7, it is determined whether the recorded data is full or not, and if it is not full, the process proceeds to step 316 to perform delay control of the second roller 8, and if it is full, step S8
Proceed to. In step S8, it is determined whether the first flag is ON, and if it is not ON, the process proceeds to step S9, and the first flag is
If so, jump to step SL2.

In the initial setting, the first flag is OFF, so proceed to step S9, and set the first flag to ONL and step SI.
Time L1 initialized from the out buffer pointer at O
Start the second timer 10e and step Sll
increments the out buffer pointer and points to the next buffer address.

Steps 39 to 311 are processes that are performed only once at the beginning, and this process reduces the initial setting delay time to 1. It is something that creates

Next, the process advances to step S12 to perform one line recording and sheet conveyance, and in step S13, the time required to record and convey the current line from the previous line is extracted from the first timer 10d, and this is stored in the buffer indicated by the in-buffer pointer. Store at 10c. Then, in step S314, the first timer 10d is initialized and activated to measure the time from the current line to the recording conveyance of the next line, and in step S15, the in-buffer pointer is incremented, and the process proceeds to step S816.

In step S16, it is determined whether the count value of the second timer foe has overflowed or not. If it has not overflowed, the process jumps to step S25, and if it has overflowed, the process moves to step S17.

The count value of the second timer 10e is determined in step 3.
10 or step 318 described below. This count value overflows and the second timer 10e
When ON is set, the second roller 8 is turned on in step 317.
rotates by one line to convey the recording sheet 1, and in step 518, the second timer 10e is set to a time t from the contents of the buffer indicated by the out-buffer pointer, and in step 319, the out-buffer pointer is incremented. to specify the next buffer address, and the process advances to step S20.

In step 320, it is determined whether or not the operation of the second roller 8 has caught up with the operation of the first roller rough. In other words, the full recording data has become very slow, and it is attempted to extract data from the out buffer pointer before the data enters the in buffer pointer. (in-buffer pointer = out-buffer pointer)
If so, proceed to step S21; otherwise, proceed to step S21.
Proceed to 25.

When the operation of the second roller 8 catches up with the operation of the first roller rough, the out buffer pointer is decremented, the second timer 10e is stopped, and the time t1 is set in the buffer indicated by the out buffer pointer. Perform processing to turn off the flag (step S21~
524).

After performing the above processing, the process proceeds to step S25, and it is determined whether or not the recorded data has ended. If not, the process returns to step S7, and if it has finished, the process proceeds to step S26, where the recording sheet 1 is ejected.

By controlling as described above, the second roller 8 operates with a predetermined time delay relative to the operation of the first roller 7.

In the above-mentioned embodiment, a sensor detects changes in the material and roll diameter of the recording sheet 1, inputs the degree of curling based on the detected values, and automatically calculates the optimal delay time for removing curling. If the setting is set as follows, the curl removal effect will be further improved.

Furthermore, in the above-mentioned embodiment, an example was shown in which a pair of rollers were used as the first conveying member and the second conveying member, but it is not necessary to limit this to roller-shaped ones, and any member capable of conveying a sheet material can be used. For example, it may be a rotating belt.

<Effects of the Invention> As described above, in the present invention, since the second conveying member is operated with a certain time delay with respect to the first conveying member, as the conveying speed of the rolled sheet material increases, the amount of slack increases. , the amount of slack decreases as the conveyance speed decreases. Therefore, regardless of the conveyance speed of the sheet material, a constant curl removal effect can always be obtained.

[Brief explanation of the drawing]

FIG. 1 is a schematic explanatory diagram of an angry heat recording device to which an embodiment of the present invention is applied; FIG. 2 is an enlarged explanatory diagram of a curl removal mechanism;
FIG. 3 is a block diagram of the control system, FIG. 4 is a flowchart showing the operation of the control system, and FIG. 5 is an explanatory diagram of the prior art. I is the recording sheet, 2 is the roll axis, 3 is the sheet holder,
4 is a platen roller, 4a is a motor, 5 is a recording head, 6 is a counter-17 is a first roller, 7a is a motor, 8
is the second roller, 8a is the motor, 9 is the sheet guide, 1
0 is a control unit, 10a is a ROM, 10b is a RAM, 10c
is a buffer, 10d is a first timer, 10e is a second timer, and lla to 11e are drivers.

Claims (1)

[Claims] a first conveyance member that conveys a rolled sheet material; and a first conveyance member that is provided downstream of the first conveyance member in the sheet material conveyance direction and that changes its rotational speed in accordance with changes in the rotational speed of the first conveyance member. What is claimed is: 1. An apparatus for removing curls in a sheet material, comprising: two conveying members; and a delay means for delaying a change in rotational speed of the first conveying member for a certain period of time and transmitting the same to the second conveying member.