JPH02131971A - Recording sheet conveyor and image recorder using the same - Google Patents

Abstract

PURPOSE:To remarkably reduce slack generated at a recording sheet irrespective of the length of a waiting state by providing control means, etc., for repeating normal and reverse operations of driving means plural times after a recording sheet is cut by cutting means. CONSTITUTION:Whether preset repetition number (n), i.e., repetition number (n) of conveyance sufficiently necessary to separate a discharge roller 5 at the rear end of a recorded sheet 1b is exceeded or not is judged, and if repeated n times, the rear end of the sheet 1b is opened out of a machine. In this case, the slack of the part between a sheet roll 1a and a platen roller 3a is y/n. Immediately thereafter, or immediately before recording of next time, it is rotated in a direction (b), rewound to a position where the position of the end of a recording sheet 1 is opposed to a recording head 3b, and stopped. It is rewound immediately after this procedure, and even if a waiting time is thereafter continued for a long period of time, a slack of the part between the roll 1a and the roller 3a becomes the sum of x corresponding to the distance between the roller 3a and a cutter 4, and 1/n of the distance (y) between the cutter 4 and the roller 5, i.e., more or less (x+y/n).

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a recording sheet conveying device for conveying a recording sheet in a predetermined direction, and particularly to a recording sheet conveying device that handles recording sheets in the form of continuous paper such as roll paper. It is suitable for use in

The present invention also provides an image recording apparatus, that is, a printer, configured using such a recording sheet conveying device. The present invention relates to an image recording device installed in a word processor, facsimile machine, or the like.

[Prior Art] FIG. 7 shows a conventional image recording device or recording sheet conveying device applied to a facsimile machine or the like.

To explain the outline of this device, 1 is a recording sheet made of thermal paper that develops color by applying heat, and a long sheet is wound into a roll, and the sheet roll la is stored in a drop-in type roll holder 2. ing.

An image is recorded on the recording sheet 1 in the recording section 3, and the recorded sheet 1 is cut from the trailing edge of the image by a cutter 4, and is discharged from the apparatus through a discharge port 5.

To explain the relationship between the roll holder 2 and the recording section 3, first, the recording section 3 includes a platen roller 3a that serves as a conveyance means for the recording sheet 1, and a large number of elements that selectively generate heat according to image signals, arranged in a line. A platen roller 3a is formed by pressing an array of line-type recording heads 3b into contact with each other by a suppressing spring 3C, and is driven by a drive transmission system from a motor 8.
The recording sheet 1 is rotated in the direction of arrow a in FIG. 7 to convey the recording sheet 1, and an image is recorded on the recording sheet 1 by causing the recording head 3b to generate heat in accordance with an image signal.

When recording is completed, the recording sheet 1 is conveyed to a cutting position by the cutter 4, the image is cut from the trailing edge, and the recorded sheet is discharged. The leading edge of the remaining recording sheet 1 is rewound to the recording section 3 and is placed on standby in preparation for the next recording. The purpose of rewinding the recording sheet 1 in this manner is to prevent a blank portion from occurring at the leading edge of the sheet during the next recording.

By the way, a recording sheet conveying device or an image recording device,
Furthermore, the structure of facsimile machines etc. that can be used with these devices will be simplified. In order to contribute to miniaturization and reduction in size, a single drive source has come to be used to convey the recording sheet. That is, the motor 8 is connected to the platen roller 3a and the discharge port roller 5 using an appropriate transmission mechanism, and the above-mentioned conveyance during recording, conveyance for cutting, conveyance for ejection, and winding of unrecorded portions are performed. Transport for return is performed.

[Problems to be Solved by the Invention] However, the above configuration has the following problems.

After recording is completed, the recording sheet cut by cutter 4 is
As the motor 8 rotates in the normal direction, the discharge port 5 rotates in the C direction and is discharged. However, at this time, since the platen roller 3a also rotates in the direction a in the figure, the leading edge of the unrecorded recording sheet is also conveyed toward the discharge port roller 5 side. Then, when the recorded recording sheet leaves the position of the discharge port roller 5, the motor 8 is reversely rotated, the platen roller 3a is rotated in the direction b, and the unrecorded recording sheet is rewound.

However, in the image recording apparatus shown in FIG. 7, the sheet roll la is stored in the drop-in type roll holder 2, so the sheet roll la does not rotate in the reverse direction, and as a result, the recording sheet When you return 1, the 7th
As shown in the figure, slack occurs at the leading edge of the sheet by the amount of unwinding. If the standby state continues for a long time, this slack will remain as a curl in the recording sheet 1, and when the next recording is performed, the leading edge of the sheet on which the image has been recorded will be curled as shown in FIG. Therefore, there have been problems such as impairing the quality of the recording sheets, the loading performance, etc.

SUMMARY OF THE INVENTION An object of the present invention is to solve these problems and provide a recording sheet conveying device and an image recording apparatus that can significantly reduce the slack that occurs in recording sheets regardless of whether the standby state is long or short.

[Means for Solving the Problems] In order to achieve such an object, a sheet conveying device according to an embodiment of the present invention includes first and The second conveying means, the cutting means disposed between the first and second conveying means for cutting the recording sheet, and the single driving source for the first and second Wl conveying means, capable of forward and reverse operation. The driving force of the driving means is applied to the first conveying means so that the first conveying means is driven in the direction of conveying the recording sheet downstream and upstream, respectively, in accordance with forward and reverse rotation of the driving means. a first transmission means that transmits the driving force to the conveyance means; and a second transmission means that transmits the driving force of the drive means to the second conveyance means so that the second conveyance means is driven only in the direction of conveying the recording sheet downstream.
The apparatus is characterized by comprising a transmission means and a control means for repeating the forward and reverse operation of the drive means a plurality of times after the cutting means cuts the recording sheet.

Furthermore, in an image recording apparatus according to another aspect of the present invention, a recording means for recording on a recording sheet, a first conveying means for conveying the recording sheet with respect to a recording position by the recording means, a cutting means for cutting the recording sheet at the rear end side of the recorded image, a second conveying means for conveying the cut portion of the recording sheet in the ejection direction, and a vehicle for the first and second conveying means. A driving means serving as a driving source and capable of forward and reverse operation, and a first conveying means such that the first conveying means is driven in a direction to convey the recording sheet downstream and upstream, respectively, in accordance with forward and reverse rotation of the driving means. , a first transmission means for transmitting the driving force of the driving means to the first conveying means; and a first transmission means for transmitting the driving force of the driving means to the second conveying means so that the second conveying means is driven only in the direction in which the recording sheet is ejected. and a control means for repeating the forward and reverse operation of the driving means a plurality of times after the recording sheet is cut by the cutting means.

[Function] According to the present invention, by driving the first conveying means disposed on the upper waterfall side and the second conveying means disposed on the downstream side in multiple steps, the recording sheet storage section and the first conveying means are driven. There will be less slack between.

That is, for example, it is divided into n times and transported (discharged) to the downstream side.
If the conveyance (rewinding) to the upstream side is repeated, the distance from the recording position to the cutting means position will be X, and the distance from the cutting position to the second position will be
When the distance to the transport means position is y, (x+y/n
) is the amount of slack. On the other hand, transport to the downstream side is
Since the amount of slack in the case of repeating n times is (x+y), in the present invention, by repeating ejection and unwinding n times, the amount of slack is (y
-y/n) decreases.

[Example code] Hereinafter, the present invention will be explained in detail with reference to the drawings.

FIG. 1 shows an example of the configuration of a facsimile machine to which a recording sheet conveying device or an image recording device according to an embodiment of the present invention is applied. A code is attached.

Here, reference numeral 6 denotes a document reading section, in which the document 7 stacked on the top cover is separated one by one by a separation roller 6a, conveyed at a constant speed by a conveyance roller 6b, and the surface of the document is irradiated with light by a light source 6c. , the reflected light is directed to a photoelectric conversion element 6f such as a CCD via a mirror 6d and a lens 6e, and the original information is converted into an electrical signal and transmitted to a predetermined recording section.

The recording unit 3 presses the platen roller 3a, which serves as a conveyance means for the recording sheet 1, as described above, and the line-type recording head 3b, which is formed by arranging in a row a number of elements that selectively generate heat according to image signals. They are pressed together by spring 3C. In this example, the platen roller 3a, which is driven by the transmission system shown in FIG. 2 from the motor 8, is rotated in the direction of the arrow a in FIG. It is configured to record an image on the recording sheet 1 by generating heat accordingly.

The recorded recording sheet is cut from the unrecorded portion at the rear end of the image by a cutter 4, and is discharged from the apparatus by a discharge port 5. Further, unrecorded portions are rewound to prevent blank portions, but in this example, the following transmission system and control system are employed to reduce slack.

FIG. 2 shows a transmission mechanism based on a wooden example. Here, 80 is a shaft of the motor 8 which can be rotated in forward and backward directions, and 90a and 90b are used to control the rotation of the motor shaft 80 between the platen roller 3a and the discharge port roller 5.
This is a reduction gear for transmitting to 0.

30a is a platen roller gear fixed to the shaft of the platen roller 3a, and meshes with the reduction gear 90b. That is, the platen roller 3a is driven by the normal rotation of the motor 8 in the direction a in the figure, which conveys the recording sheet in the discharge direction, and is also driven by the reverse rotation in the direction b, which rewinds the recording sheet. In addition, lO and 50 are respectively the outlet-
This is a one-way clutch and gear provided on the side of the roller 5, which allows the discharge port roller 5 to rotate only in the direction of ejecting the recording sheet (direction C). FIG. 3 shows an example of the configuration of a control system according to an embodiment of the present invention.

Here, 100 is a CPU in the form of a microcomputer, and in the tree example, it is also used as a main control unit for executing control procedures for each part of the facsimile machine, including processing procedures to be described later with reference to FIG. 102 is a ROM that stores programs corresponding to the processing procedure shown in FIG. 4 and other procedures, fixed data for transport control, and the like. A RAM 104 has an area for storing image data and data used for control calculations, and an area used as a counter to be described later.

Reference numeral 106 denotes a document reading system including the photoelectric conversion element 6f shown in FIG. A communication device 108 transmits image data read from a document to other stations and receives image data from other stations. Reference numeral 110 denotes a switch group provided on the operation panel, etc., including a transmission switch and others. Reference numeral 112 denotes a group of sensors provided to control each part and monitor the status.

Reference numeral 120 denotes a display unit provided on an operation panel or the like for displaying messages, etc., and reference numeral 126 denotes a reading system drive unit including a drive unit for conveying a document, a driver for the photoelectric conversion element 6f, etc. in FIG. Further, 90 is a transmission mechanism including a gear train shown in the second figure, and 128 is a cutter drive section that drives the cutter 4.

FIG. 4 is a flowchart showing an example of the procedure for transporting a recording sheet related to a wood example, and FIGS. The specific operation will be explained. In addition, in the following,
is the amount commensurate with the conveyance distance from the recording position to the cut position, taking into account that the recording sheet 1 is cut at an appropriate position on the trailing edge side of the recorded image, and y is the distance from the cut position to the ejection port - la 5
n is the number of times the ejecting operation or rewinding operation is repeated.

When the recording unit 3 completes the recording process for one unit of image data, that is, for example, the recording process for one page of image data transmitted from another station (step 51), in step S3 the motor 8 is activated by the amount corresponding to the ffix. Drive. Along with this, the platen roller 3 is moved through the transmission mechanism shown in the second figure.
a and the discharge port 5 are rotated in the a direction and the C direction, respectively, and the portion on the trailing edge side of the image of the recording sheet 1 is rotated in the fifth direction.
It is stopped when it is conveyed to the cutting position shown in Figure (A). Then, in step S5, the cutter drive unit 1
The cutter 4 is driven via 28 to cut the recording sheet 1.

Next, in step S7, a counter C is used as an index for dividing the ejection or rewinding operation into several times (n times).
is cleared, and the motor 8 is rotated forward by a predetermined amount in step S9. That is, the platen roller 3a and the discharge port roller 5 are rotationally driven in the a direction and the C direction, respectively, as shown in FIG.
As shown in B), the rear end of the recorded sheet lb is at a distance Jiff.
The recorded sheet lb and the unrecorded sheet 1 are conveyed by an amount up to 1/n of y and then stopped. At this time, there is no slack between the roll sheet la portion of the wound recording sheet 1 and the platen roller 3a.

Then, in step 511, the motor 8 is reversely rotated by the predetermined amount. At this time, the platen roller driven by the transmission mechanism 9o was rotationally driven in the b direction, and the unrecorded sheet 1 was rewound until the leading edge of the sheet came to the cutter 4 position, as shown in FIG. 5(C). It will be stopped later. During this operation, the discharge port 5 does not rotate in the opposite direction to the direction C due to the presence of the one-way clutch 10 and remains stopped.
Recorded sheet lb is not affected. Also, the amount of slack between the sheet roll la and the platen roller 3a that occurs at this time is 1/ of the distance my between the cutter 4 and the discharge port-la 5.
It is n.

After this, in step S13, the counter C is incremented by +1,
In step 515, it is determined whether or not the number of repetitions n set in advance, that is, the number n of repetitions of conveyance that is necessary and sufficient for the rear end of the recorded sheet lb to leave the discharge port roller 5, is determined, and a negative determination is made. If so, the process returns to step S9. and,
When the operations shown in FIGS. 5(B) and 5(C) are repeated n times, the rear end of the recorded sheet lb is opened to the outside of the machine as shown in FIG. 5(D). At this point, the amount of slack in the portion between the sheet roll la and the platen roller 3a is y/n.

Immediately after this, or immediately before the next recording process, the fifth
Rotate the recording sheet 1 in the b direction as shown in Figure (E).
The tape can be rewound and stopped until the tip of the tape faces the recording head 3b.

Even if the rewinding is performed immediately after the procedure in step 515 and the standby state continues for a long time, the amount of slack in the portion between the sheet roll la and the platen roller 3a corresponds to the distance between the platen roller 3a and the cutter 4. The sum of X and 1/n of the distance IlIIy between the cutter 4 and the ejection port 5, that is, at most (x + y/n), which is the sum of the distance IlIIy between the cutter 4 and the ejection port 5. Amount of slack (x+
The amount of slack is much smaller than y).

Therefore, even if the next recording is performed after waiting for a long time in that state, the recording sheet is less likely to curl.

For example, as shown in Figure 6, if we consider the case where the ejection or rewinding operation is performed in two steps,
(-X")'+"y2:y+-yt) slack will occur, but in the wooden example, only X"yr slack will occur.In addition, in the above configuration, the number of times ejection or rewinding is repeated Of course, the number of times can be set to any desired number of times or more. Also, regarding the configuration of the transmission mechanism, a single driving source can be set to the first
It connects the platen roller, which is the conveyance means, and the discharge port roller, which is the second conveyance means (discharge means) provided on the discharge section side in the above example, and allows the latter to rotate only in the discharge direction. Needless to say, the configuration is not limited to the one shown in Figure 2. Furthermore, the platen roller 3a in the above example functions as a t-th conveying means for conveying during recording processing and conveying in the ejection direction and rewinding direction after the recording process is completed, and also functions as a t-th conveying means for conveying the recording sheet to the recording head 3b. Although it also functions as a regulating member that regulates the surface, both functions may be separated. That is, the first conveying means is not necessarily in the form of a Braden roller, I,! ¥! It does not have to have. Also,
The first and second feeding means are not limited to rollers, and may be, for example, belts suspended between pulleys.

In addition, although the above example describes the case where the present invention is applied to a facsimile machine, it goes without saying that the present invention can also be applied to printers, word processors, and others.

In addition, in the above example, a thermal recording head in which heating elements are arranged in a line in the width direction of the recording sheet was used, and a recording sheet made of rolled thermal paper was used. Of course, it is not limited to these. That is, the recording method can be an inkjet recording method, a laser recording method, or the like, and in this case, the recording sheet can be so-called plain paper, film, or the like. Even when using a thermal method, the recording sheet may be plain paper, etc., as long as thermal transfer is performed using an ink ribbon or the like. In addition to the method in which printing is performed line by line, it is also possible to use a serial printing method in which printing is performed by scanning a print head using a carriage or the like. [Effects of the Invention] As explained above, according to the present invention, the slack that occurs in the recording sheet can be significantly reduced, and curling can occur in the recording sheet, regardless of the presence or absence of a waiting time after the recording process is completed, and regardless of the length of the waiting time. I was able to make it more difficult. Further, the configuration for this purpose requires almost no changes or additions to parts, and there is no need to change the design of the shape, so there is almost no increase in cost.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a configuration example of a facsimile machine using a recording sheet conveying device or an image recording device according to an embodiment of the present invention, and FIG. 2 is a schematic diagram showing a configuration example of a transmission mechanism according to the present embodiment. Fig. 3 is a block diagram showing an example of the configuration of the control system of the apparatus shown in Fig. 1, Fig. 4 is a flowchart showing an example of the recording sheet conveyance processing procedure, and Figs. 5 (^) to (E) are FIG. 6 is a cross-sectional view for explaining the effect of the wood example; FIG. 7 is a cross-sectional view for explaining the sequential operation of this example; FIG. 7 is for explaining the conveyance of a recording sheet by a conventional sheet conveyance device or image recording device. FIG. 8 is an explanatory diagram for explaining the curling of a recording sheet that occurs when it is conveyed according to a conventional example. 3b... Recording head, 4... Cutter, 5... Discharge port-ra, 8... Motor, 10... One-way clutch, 30a, 50, 90a, 90b... = gear, 90... Transmission mechanism, 100-CPIJ 106...Reading system, 10B...Communication device, 126...Reading system drive section, 128...Cutter yjA moving section. DESCRIPTION OF SYMBOLS 1... Recording sheet, la... Sheet roll, tb... Recorded sheet, 2... Roll holder, 3... Recording part, 3a... Platen roller, Fig.

Claims (1)

[Scope of Claims] 1) first and second transport means disposed on the upstream and downstream sides of the recording sheet transport path;
a cutting means disposed between the conveying means to cut the recording sheet; a driving means that serves as a single drive source for the first and second conveying means and capable of forward and reverse operation; The driving force of the driving means is transmitted to the first conveying means so that the first conveying means is driven in the direction of conveying the recording sheet downstream and upstream, respectively, in accordance with rotation and reverse rotation. a first transmission means; and a second transmission means only in the direction of conveying the recording sheet downstream.
a second transmission means for transmitting the driving force of the drive means to the second conveyance means so that the conveyance means is driven; and after the cutting means cuts the recording sheet,
A recording sheet conveying apparatus comprising: a control means for repeating forward and reverse operation of the driving means a plurality of times. 2) The first conveying means is arranged near the recording position on the recording sheet, the cutting means has a cutting member that cuts the recording sheet at the rear end side of the recorded image, and the second conveying means cuts the recording sheet at the rear end side of the recorded image. 2. The recording sheet conveying device according to claim 1, further comprising a discharge means for discharging the recorded sheet portion. 3) a recording means for recording on a recording sheet; a first conveying means for conveying the recording sheet with respect to a recording position by the recording means; and a rear end side of the recorded image on the recording sheet. a second conveying means for conveying the cut portion of the recording sheet in the ejection direction; and a single driving source for the first and second conveying means, which can be operated in forward and reverse directions. a driving means, such that the first conveying means is driven in the direction of conveying the recording sheet downstream and upstream, respectively, in accordance with forward and reverse rotation of the driving means; a first transmission means for transmitting a driving force to the first conveyance means;
a second transmission means for transmitting the information to the conveying means; and after the cutting means cuts the recording sheet;
An image recording and conveying apparatus comprising: a control means for repeating forward and reverse operation of the drive means a plurality of times.