JPH0361254A - Decurl mechanism and recording device using decurl mechanism - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a decurling mechanism for correcting curling of a sheet material wound into a roll, and a recording apparatus having the decurling mechanism.

<Prior Art> Today, office equipment such as facsimile machines and printers are widely used, and the recording systems of these devices generally use a roll sheet in which a long recording sheet is wound around a core.

Since this sheet material is wound into a roll, it is likely to be curled (hereinafter referred to as r-curl), and the curled sheet material is likely to jam during transportation. For this reason, many recording apparatuses that use the roll sheet are equipped with a decurling mechanism to remove or reduce the curl.

An example of the decurling mechanism is one constructed as shown in FIG. 15, for example. This is the main body 81 and the lid 8
2 can be opened and closed by a pin 83, and one main body 8
1 includes a roll holder 84, a platen roller 85, a counter 86, and a guide member 87a that constitutes a decurling mechanism.
The other lid 82 is provided with a guide member 87b that constitutes a decurling mechanism together with the recording head 88 and the guide member 87a.

In the device described above, a sheet roll 89a in which a sheet material 89 is wound into a roll is loaded, and the sheet material 89 is conveyed by the rotation of the platen roller 85, and the recording head 8
8 forms an image, cuts it with a cutter 86, and discharges it to the outside of the apparatus.
When passing through the bending passage formed by 7a and 87b, the curl is reduced when it is bent in the direction opposite to the curl.

As another example, a decurling mechanism constructed as shown in FIG. 16 has been proposed. This configuration is based on the guide shaft 9
An arm 91 is rotatably attached to both ends of the arm 91, and a decal shaft 92 is rotatably attached to the rotary tip of this arm 91. The arm 91 is always biased counterclockwise by a spring, and when the platen roller 85 rotates in the direction of the arrow, the rotational force is transmitted through a friction clutch (not shown), causing the arm 91 to rotate clockwise. It is configured as follows. Furthermore, the main body 81
Stoppers 93 and 94 for restricting rotation of the arm 91 are fixed at predetermined positions.

In the above configuration, when the platen roller 85 rotates in the direction of the arrow, the sheet material 89 is conveyed. At this time, the arm 91 also rotates in the clockwise direction, and when it comes into contact with the stopper 94, the friction clutch slips and the rotation of the arm 91 is stopped. The sheet material 89 thus conveyed is conveyed from the roll 89a through the guide shirt 90 and is conveyed by the decal shaft 92 while being bent in the opposite direction to the curl, so that the curl is corrected.

When the rotation of the platen roller 85 stops, the arm 91 returns until it comes into contact with the stopper 93 due to the biasing force of the spring, and enters a standby state.

<Problems to be Solved by the Invention> The curl state of the sheet material 89 differs depending on the roll diameter, as well as the thickness and type of the sheet material 89, the time elapsed since the sheet material 89 was wound around the roll core, etc. For example, a thermal sheet made of thermal paper has a thickness of about 65 μm, but a normal sheet made of plain paper on which ink is transferred and recorded is thicker, about 85 μm, and the roll diameter is the same. The normal sheet also has a greater degree of curl than the heat-sensitive sheet (it has tighter curls).

However, in the decurling mechanism shown in FIG. 15, the bending angle formed by the guide members 87a and 87b for curl correction is constant.

Further, in the decal mechanism shown in FIG. 16, the arm 9
The amount of curl correction (curl correction effect) is determined by the position of arm 91 (decal shaft 92).
The position of the decal shaft 92) is kept constant by a stopper 94.

For this reason, for example, if the bending angles of the guide members 87a and 87b and the fixing position of the stopper 94 are set to match the heat-sensitive sheet, the curl correction effect will be insufficient when using a normal sheet; When the sheet is used, the curl correction effect is too great and the sheet warps in the opposite direction to the curling direction, causing a paper jam due to poor sheet conveyance.

In particular, in the case of the recording section of a fusing device, a thermosensitive sheet and a normal sheet can be used together, and the amount of curl correction (curl correction effect) is fixed as shown in Figures 15 and 16 above. However, there is a drawback that curls cannot be properly corrected depending on the thickness, type, etc. of the sheet material 89.

An object of the present invention is to solve the above-mentioned conventional problems, and to provide a decurling mechanism that can easily adjust the curl correction effect and appropriately correct curls according to the thickness, type, etc. of the sheet material, and a recording device having the decurling mechanism. Our goal is to provide the following.

Means for Solving the Problems> A typical means of the present invention for solving the problems described above includes a conveyance means for conveying a sheet material, a guide member for guiding the conveyance of the sheet material, a decal member for bending and guiding the conveyed sheet material; a moving means for moving at least one of the guide member and the decal member; and urging the moving means in a direction in which the bending of the sheet material becomes greater. The decurling mechanism is characterized in that the decurling mechanism is provided with a biasing means for changing the biasing force of the biasing means, and a switching means for switching the biasing force of the biasing means.

Effect> In the above means, when conveying the sheet material, the moving means stops in a state where the tension applied to the sheet material and the urging force of the urging means are balanced. Therefore, when the tension is large, the influence of the biasing force on the moving means is small, and the amount of movement of the moving means is small, so the amount of bending of the sheet material is small. On the other hand, when the tension is small, the amount of movement of the moving means increases, contrary to the above, and the amount of bending of the sheet material increases.

Here, the urging force of the urging means can be easily switched by a switching means. For example, when the curls are tightly formed, the urging force can be changed to a large value (to increase the curl correction effect), or when the curls are too tight, If it is not tight, switch the biasing force to a smaller value (lower curl correction effect),
Curls can be appropriately corrected depending on the thickness, type, etc. of the sheet material.

Furthermore, by providing the guide member and decal member separately in the main body of the device and the lid, the guide member and decal member are separated by a large distance when the lid is opened, making it easier to load the sheet material. .

Furthermore, by making the moving force of the moving means larger than the urging force of the urging means against the moving means, the moving means can be operated in a direction in which the sheet material does not bend against the urging of the urging means, It is possible to prevent the sheet material from being unnecessarily decurled in the conveyance standby state.

Furthermore, by increasing the self-holding force of the drive source of the moving means to a certain extent, the relationship between the guide member and the decal member can be maintained appropriately.

Further, the recording device is configured by providing the decurling mechanism, and the conveying means and the moving means are operated by the same driving source, and the driving source is driven to transport the sheet material backward from the counter to the recording means. By occasionally returning the moving means to the initial position, the moving means is always located at the initial position in the recording standby state.

Further, by setting the output of the drive source to be larger when the sheet material is being transported in a direction opposite to the recording direction than when the sheet material is being transported in the recording direction, it is possible to stably transport the sheet material. It is.

<Embodiment> Next, an embodiment in which the above means is applied to a facsimile machine will be described.

[First example]

1 and 2 are perspective explanatory views of the recording system of the facsimile apparatus, and FIG. 3 is a cross-sectional explanatory view of the entire facsimile apparatus.

As shown in FIG. 3, this facsimile apparatus is comprised of a recording system B having a decurling mechanism A and an original reading system C.

First, the overall configuration will be briefly described with reference to FIG. 3. Recording system B has a device main body 1 with a lid 2 that can be opened and closed by a shaft 3, and the lid 2 is connected to the main body l by a click mechanism (not shown). It is configured so that it can be locked on the lid body 2.
On the back side, a supply roll 50a and a take-up roller 50b, which are formed by winding an ink sheet 50 formed by applying thermal transfer ink onto a base such as a polyester film, are attached. Further, a roll 5a of a sheet material 5 made of plain paper wound into a roll is loaded into a roll holder at a predetermined position on the back side of the main body of the recording system. The ink sheet 50 and the sheet material 5 are connected to a platen roller 6a constituting a conveying means.
conveyed by the rotation of the At this time, the sheet material 5 is bent in a direction opposite to the curling direction when passing through the decurling mechanism A, thereby correcting the curl.

Then, a predetermined image is formed by melting the ink of the ink sheet 50 and transferring it to the sheet material 5 in the recording means 6, and the sheet material 5 after recording is cut by the cutter 7 and discharged by the discharge roller 8 to the stacker. 9. Further, the ink sheet 50
is separated from the sheet material 5 by a separation shaft 51 before reaching the cutter 7, and is wound up by a take-up roll 50b.

The supply roll 50a and the take-up roll 50b are rotated while being applied with tension by a drive system 50c (see FIG. 12) so as not to loosen.

The original reading system C places a plurality of originals 11 on the original TiW table 10 formed on the upper surface of the lid 2, and when a reading operation is performed, among the plurality of originals 11 that have been placed,
Several documents 11 from the bottom are conveyed by a preliminary conveyance roller 12a and a pressure contact member 12b that is in pressure contact with the preliminary conveyance roller 12a, and are conveyed by a separation roller 13.
A and a pressure contact member 13b that presses against the pressure contact member 13b are configured to separate and supply one sheet at a time. The document 11 that has been further separated is transferred to transport roller pairs 14a, 14b and 15a, 15.
While being conveyed by the light source 16, the reflected light reaches a photoelectric conversion element 19 such as a CCD via the ξ gear 1f and the lens 18, where it is converted into an electrical signal, and this signal is in copy mode. is transmitted to its own recording system B,
In the case of facsimile mode, the information is configured to be transmitted to the recording system of another machine.

Next, the configuration of each part of the recording system B having the decurling mechanism in the facsimile machine will be explained in detail.

The roll holder 4 is formed with an open top, and is arranged at the back side of the recording system main body 1. The roll holder 4 is loaded with a sheet roll 5a, and the outer circumferential surface of the roll 5a and the inner surface of the holder 4 come into contact with each other, creating frictional resistance. That is, when the sheet material 5 is drawn out, when the roll 5.3 has a large diameter and is heavy, a large frictional resistance is generated, and as the sheet material 5 is drawn out and the weight of the roll 5a decreases, the frictional resistance also increases. Decrease. This frictional resistance has the effect of applying tension to the sheet material 5 when it is drawn out, and the tension applied to the drawn out sheet material 5 changes in proportion to the magnitude of the frictional resistance.

Recording means 6 for recording a predetermined image on the sheet material 5
The configuration consists of a platen roller 6a and a recording head 6b. The platen roller 6a is a roller-shaped member made of a material with a high friction coefficient such as hard rubber, which is rotatably attached to the main body 1, and is connected to a motor 2 serving as a driving source.
It is configured to be driven at o. That is, as shown in FIG. 1, the rotational force of the motor 20 is transmitted from a gear 21a fixed to the motor shaft via an intermediate gear 21b to a gear 21c fixed to the roll shaft of the platen roller 6a, causing the platen roller 6a to rotate. do. The sheet material 5 and the ink sheet 50 are conveyed by the rotation of the platen roller 6a, and the platen roller 6a also serves as a means for conveying the sheet material 5 and the ink sheet 50.

The recording hendroid b prints the ink sheet 150 in response to both signals.
By heating the ink, the ink on the ink sheet 5° is melted and transferred to the sheet material 5, thereby forming the sheet material 5.
6, which is configured to press a platen roller 6a through a sheet material 5 and an ink sheet 50. Specifically, it is rotatably attached to the lid body 2 by a shaft 6c, and this The platen roller 6a is configured to be pressed by a compression spring 6d when the lid body 2 is closed. Therefore, the platen roller 6a and the recording head 6
When the platen roller 6a rotates with the sheet material 5 and the ink sheet 5o inserted between the spaces between the sheet material 5 and the ink sheet 50, the sheet material 5 and the ink sheet 50 are conveyed.

The recording head 6b in this embodiment has a large number of heating elements 6b that generate heat when energized on the surface that contacts the ink sheet 50.
, are arranged in the width direction of the ink sheet 5o, a so-called line type thermal head is used, and the heating element 6b
, by energizing according to the image signal)
50 is selectively heated to melt the ink in the heated portion and transfer it to the sheet material 5, thereby performing recording.

Next, the cutter 7 has a fixed blade 7a and a driving blade 7b in this embodiment.
A rotary canter consisting of Specifically, the fixed blade 7a is fixed to the main body 1, and the driving blade 7b is attached so as to be rotatable about a shaft 7c, and when the driving blade 7b is rotated by the driving means, it rubs against the fixed blade 7a. This is for cutting the sheet material 5.

The drive blade 7b may be configured to be driven by the motor 20 that drives the platen roller 6a, or may be driven by another independent motor.

The sheet material 5 canted by the cutter 7 is transferred to a discharge roller 8 driven by a discharge motor 8a (see FIG. 12).
However, since the sheet material 5 used for recording is wound around the winding core 5b, it is curled when it is pulled out from the sheet roll 5a.

The curl varies depending on the diameter of the roll 5a.

For example, the curl that occurs when the roll diameter is large has a small curl height h shown in FIG. 4(a), and as the roll diameter becomes small, the curl height h increases, and
It curls up as shown in c).

In the apparatus of this embodiment, the curl is corrected when the sheet material 5 passes through the decurling mechanism A.

That is, the position of the guide shaft 23 serving as a guide member is configured to be movable with respect to the decal shaft 22 serving as a decurling member, and the sheet material 5
The curl is corrected by being bent in the opposite direction to the curl direction when being guided.

Further, the guide shaft 23 is biased against the sheet material 5 by a biasing means to be described later, and there are two cases in which the guide shaft 23 is loaded with a large diameter roll 5a as shown in FIG. 5 and when a small diameter roll 5a as shown in FIG. 6 is loaded. The decal effects are different.

Here, the structure of the decurling mechanism A will be specifically explained.

The decal shaft 22 is rotatably attached to a mounting member 24 fixed to the lid body 2, as shown in FIGS. 1 and 2. The mounting member 24 is composed of a flat plate 24a that serves as a guide for the sheet material 5, and a placket 24b formed upright at the ii4 end of the flat plate 24a. The distance between the arms supporting both ends of the guide shaft 23 is smaller than the distance between the arms supporting both ends of the guide shaft 23. and said placket 2
A decal shaft 22 is rotatably attached to 4b.

As shown in FIGS. 5 and 6, this decal shaft 22 always has a constant position with respect to the main body 1 when the lid 2 is closed, and the position of the sheet material 5 with respect to the platen roller 6a at this time is constant. It is disposed on the upstream side in the conveyance direction and at a position where the angle at which the sheet material 5 is introduced into the platen roller 6a is not too large.

Further, a guide 37 is provided on the main body 1 facing the decal shaft 22 to guide the sheet material 5 pulled out from the roll 5a to the platen roller 6a. One end of this guide 37 extends to the vicinity of the platen roller 6a, and the other end is configured to be integrated with the roll holder 4.

On the other hand, the guide shaft 23 is configured to be movable relative to the decal shaft 22 by a moving means. The structure of this moving means is as shown in the perspective explanatory view of FIG. 7 and the cross-sectional explanatory view of FIG.
Two arms 26 are fixed to the shaft 25 , and a guide shaft 23 is rotatably attached to the tips of both arms 26 .
When the arm 26 rotates, the arm 26 integrally rotates, thereby allowing the guide shaft 23 to move relative to the decal shaft 22.

The shaft 25 is rotatably attached to the main body 2 via a bearing 27, and a clutch flange 28, a clutch gear 29, and a spring clutch 30 are attached to one end of the shaft, and rotational force in one direction is transmitted to the shaft 25. It is configured as follows.

The clutch flange 28 has a cylindrical portion 28a and a collar portion 28b.
It is attached so that it rotates in the same direction as the shaft 25 by means of a rotation pin 31.

The clutch gear 29 is made up of a cylindrical part 29a and a gear part 29b, the inner diameter of the hole through which the shaft 25 is inserted is slightly larger than the outer diameter of the shaft 25, and the clutch gear 29 is rotatably attached to the shaft 25. There is.

The spring clutch 30 is formed by winding a spring steel wire, a spring steel strip, a plastic wire, etc. into a coil shape, and the spring clutch 30 is formed by winding a spring steel wire, a spring steel strip, a plastic wire, or the like into a coil shape.
8a, 29a, one end 30a of which is locked to the flange 28b of the clutch flange 2,
Further, the other end 30b is bent at a substantially right angle to stand up.

The spring clutch 30 transmits the rotational force of the clutch gear 29 to the clutch flange 28 in only one direction, and not in the other direction. That is, when the clutch gear 29 rotates in the direction of arrow a in FIG.
0 is loosened and becomes a free state, and no rotational force is transmitted to the clutch flange 28. On the other hand, when the clutch gear 29 rotates in the opposite direction of the arrow -a (hereinafter, the minus sign indicates the opposite direction of the arrow), the spring clutch 30 tightens the cylindrical parts 28a and 29a to be in a locked state, and the clutch flange The rotational force is transmitted to 28, and the rotational force for moving the guide shaft 22 in the direction indicated by the arrow is transmitted.

The drive source for rotating the clutch gear 29 is the same as the drive source for rotating the platen roller 6a,
It is driven by a motor 20. That is, as shown in FIG. 1, the driving force of the motor 20 is transmitted through the gears 21a to
The gear 21c attached to the platen roller shaft meshes with the gear portion 29b of the clutch gear 29 via the intermediate gear 21d.

Therefore, as shown in FIG. 1, when the motor 20 rotates forward in the direction of arrow C, the platen roller 6a rotates in the direction of arrow d, and the clutch gear 29 rotates in the direction of arrow a. That is,
When the platen roller 6a rotates in the direction of drawing out the sheet material 5 in the direction of arrow C, the spring clutch 30 is in a free state.

Further, when the motor 20 rotates in the opposite direction of arrow -C, the platen roller 6a rotates in a direction to reversely feed the sheet material 5, and at this time, the clutch gear 29 rotates in the direction of arrow -a, causing the spring clutch 3o to rotate in the direction of arrow -A. is in a locked state and transmits the rotational force that rotates the guide shaft 23 in the direction indicated by the arrow in FIG.

Next, the structure of a biasing means for biasing the guide shaft 23 so as to be balanced with the tension of the sheet material 5, and a switching means for switching the biasing force of this biasing means will be explained.

As shown in FIGS. 7 and 8, a pulley 33 is fixed to the other end of the shaft 25 by a rotation pin 32. As shown in FIGS. A groove 33a is formed on the circumferential surface of the pulley 33, and a hook 34a is protruded from a predetermined position, and one end of a tension spring 35 serving as a biasing means is engaged with the hook 34a.

In addition, as shown in FIGS. 2 and 9, the pulley 33 of the main body 1
A switching lever 40 serving as a switching means is swingably provided at a predetermined position on one side of the side where the switching means is arranged via a pin 41, and stoppers 43, 44 that limit the swinging range of the switching lever 4o are provided. is provided.

A hook 42 is provided in the layered movement chamber of the switching lever 40, and the other end of the tension spring 35 is engaged with the hook 42. That is, the tension spring 35 is attached with tension between the hook 34a and the hook 42, and the tension of the tension spring 35 causes the pulley 33 to
is constantly biased in the direction of arrow f in FIG. 7 (the direction in which the decurling effect by the guide shaft 23 becomes greater).

The switching lever 40 switches the tension force of the tension spring 35, and when it is in the position shown by the solid line in FIG. The extension of the tension spring 35 is slight and the tensile force is small, and the rotational force of the pulley 33 in the direction of arrow f is weak, that is, the curl correction effect is weak.

Furthermore, when the switching lever 40 is in the position shown by the two-dot chain line in FIG.
5 has a long elongation and a large tensile force, and the rotational force of the pulley 33 in the direction of the arrow f is strong, that is, the curl correction effect is strong.

That is, by rotating the switching lever 40, the tensile force of the tension spring 35 can be changed to weaken or strengthen the curl correction effect.

Note that when the switching lever 40 is rotated in the direction of the arrow in FIG. 9 from the position shown by the solid line in FIG. 9 to the position shown by the two-dot chain line in the same figure (when switching the spring force of the tension spring 35). ,
At first, the tension spring 35 stretches and the resistance to rotation in the same direction increases, but when the switching lever 40 rotates from an almost vertical position to the stopper 44 side (the tension spring 35
(when the center line of the tension spring 35 moves beyond the pin 41 toward the stopper 44), the spring force of the tension spring 35 changes to a force that rotates the switching lever 40 in the direction of the arrow, and the switching lever 40 moves without applying any external force. ) 7 Rotate until it touches par 44.

Furthermore, stoppers 36 and 38 are provided at predetermined positions on the main body 1 and within the rotation range of the arm 26, as shown in FIG. 7 and FIGS. 1O (a) to (C). The stopper 36 comes into contact with the arm 26 when it rotates in the direction of arrow -b in FIG. This is to set the maximum amount of coating. Further, the stopper 38 comes into contact with the other end 30b of the clutch spring 30 when the arm 26 rotates in the direction indicated by the arrow in FIG. 26) to prevent rotational force from being transmitted.

That is, the stoppers 36 and 38 limit the range of movement of the arm 26 (guide shaft 22), and when the clutch gear 29 rotates in the direction of arrow a shown in FIG. 7, the spring clutch 30 is loosened and becomes free. No rotational force is transmitted to the clutch flange 28, but the tension spring 35
As a result, the arm 26 rotates in the direction of the arrow f shown in the figure, contacts the stopper 36, and stops at the same position (
(See FIG. 10(A)).

Furthermore, when the clutch gear 29 rotates in the red mark -a direction shown in FIG. (See figure (B)). When the other end 30b of the spring clutch 30 rotates until it comes into contact with the stopper 38, the spring clutch 30 is loosened and becomes free, and no rotational force is transmitted from the clutch gear 29 to the clutch flange 28, and the arm 26 is moved to the other end. 30
b stops at the position where it touches the stopper 38 (10th
(See figure (C)).

Next, the operation of recording using the recording system B having the decurling mechanism A configured as described above will be explained with reference to FIGS. 5 and 6.

First, the lid 2 is opened, the sheet roll 5a is loaded into the roll holder 4, and the leading edge of the sheet is pulled out and set on the platen roller 6a. At this time, as shown in FIGS. 1 and 2, the decal shaft 22 is attached to the lid 2 and the guide shaft 23 is attached to the main body 1, so when the lid 2 is opened, both shafts 22 and 23 are attached. The sheet materials 5 can be easily set at large distances.

Next, when the recording start signal is input with the lid body 2 closed,
The motor 20 rotates normally, the platen roller 6a rotates in the direction of the arrow d, and the sheet material 5 and the ink sheet 50 move in the direction of the arrow e.
conveyed in the direction. In synchronization with this conveyance, the recording head 6b
The heating element 6b+ selectively generates heat and the ink sheet 50
A predetermined recording is performed by melting the ink and transferring the melted ink onto the sheet material 5. Then, when the sheet material 5 is conveyed, the decurling mechanism A operates to correct the curl of the sheet material 5.

That is, the normal rotation driving force of the motor 20 is the crankshaft gear 29.
However, as described above, the spring clutch 30 is in a free state and the clutch gear 29 is rotating idly with respect to the flange 28.

On the other hand, as shown in FIG. 7, a biasing force in the direction of arrow r is acting on the shaft 25 due to the tensile force of the tension spring 35.
The arm 26 rotates in the direction of the arrow
3 moves and stops at a position balanced with the tension of the sheet material 5.

As a result, the conveyance path of the sheet material 5 is wound around the guide shaft 23 from the sheet roll 5a in the curling direction.
Next, it is bent by the decal shaft 22 and wrapped around the shaft 22 in the opposite direction to the curl.

This winding around the decal shaft 22 corrects the curl of the sheet material 5.

Here, the tension applied to the conveyed sheet material 5 is caused by the contact friction between the roll holder 4 and the roll 5a loaded on this holder 4.

That is, as shown in FIG. 5, if the weight of the roll 5a is G1 and the tension acting on the sheet material 5 is Fl, then this tension F and the rotating force of the arm 26 (due to the tensile force of the tension spring 35) The arm 26 stops at a position where the rotational torque of the pulley 33 is balanced.

As shown in FIG. 5, when the roll diameter is large, the wrapping angle at which the sheet material 5 wraps around the decal shaft 22 is θ when the tension F1 on the sheet material 5 and the rotational force of the arm 2G are balanced. Then the platen roller 6a
guided by.

On the other hand, as shown in FIG. 6, when the diameter of the roll 5a becomes smaller, the roll weight 1ct also becomes smaller (Gz<G+), and the tension F2 acting on the sheet material 5 also becomes smaller (FZ<P
I) Therefore, the arm 26 rotates further in the direction of the arrow - than when the roll diameter is large. If the rotational force of the arm 26 and the above-mentioned drag are balanced, the arm 26 will stop at that position, but if the amount of rotation of the arm 26 is greater, it will stop at the position where it contacts the stopper 36 (
(See FIG. 10(A)). At this time, the wrapping angle at which the sheet material 5 is wound around the decal shaft 22 is θ, which is smaller than the wrapping angle θ1 when the roll diameter is large.

Therefore, when the diameter of the roll 5a is large, the amount of sheet material wrapped around the decal shaft 22 is small, and as the roll diameter becomes smaller and the curl becomes stronger, the amount of sheet material wrapped becomes larger. As the amount of wrapping increases, the sheet material 5 is bent in the direction opposite to the curl, so that the curl correction effect increases. That is, the curl correction effect increases as the roll diameter, which causes stronger curling, becomes smaller.

In this embodiment, since the sheet material 5 is plain paper that curls tightly, the switching lever 40 is moved to the position indicated by the two-dot chain line in FIG.

As a result, the tensile force of the tension spring 35 increases (the rotational force of the arm 26 increases), and as shown in FIG. 5, even when the diameter of the roll 5a is large, the rotation amount of the arm 26 is large, and The winding angle at which the decurl shaft 22 is wrapped around the decal shaft 22 is smaller than θ1, and the curl correction effect is strengthened.

Note that when the tensile force of the tension spring 35 is changed to a large value by the switching lever 40, the curl correction effect becomes stronger as the diameter of the roll 5a becomes smaller as shown in FIG. The minimum value of the wrapping angle θ is determined by the position of the stone bar 36,
Therefore, if the curl correction effect is to be further strengthened, it is necessary to change the mounting position of the stopper 36 so that the wrap angle is smaller than the wrap angle θ2.

When replacing the sheet material 5 with thermal paper that is less curly than plain paper, the switching lever 40 may be moved to the solid line position shown in FIG. 9. As a result, since the rotational force of the arm 26 is small, the amount of rotation of the arm 26 in the arrow direction is small even when the diameter of the roller 5a shown in FIG. The wrapping angle becomes larger than θ2, and the curl correction effect is weakened.

In this way, by simply rotating the switching lever 40, the strength of the curl correction action can be switched, and the sheet material 5
Curls can be corrected appropriately depending on the type, thickness, etc.

FIGS. 11(A) to 11(C) show the results of an experiment in which curling of the sheet material 5 was corrected by the decurling mechanism A.

In this experiment, a sheet roll 5a wound with plain paper having a thickness of 85 μm and a length of 100 m and a sheet roll 5a having a thickness of 65 μm and a length of 10 m are used.
A sheet roll 5a wound with 0 m of thermal paper was used. Also, the outer diameter of the decal shaft 22 and guide shaft 23 is 4++a+, and the radius of movement of the guide shaft 23 is 1
It was 3s+m. Further, the rotational force of the arm 26 for plain paper was set to 1.5 kgcm, and the rotational force of the arm 26 for thermal paper was set to 1kgcm.

The curl height h was measured by cutting the sheet material 5 into an A4 size length.

In the figure, the white triangle (Δ) is the curl height h of plain paper without curl correction, the white circle (○) is the curl height h of thermal paper without curl correction, and the black triangle (mu) is the curl height h of plain paper without curl correction. The curl height h of plain paper, and the black circle (.) indicate the curl height h of thermal paper that has undergone curl correction.

For comparison, the measurement results of the curl height h of thermal paper and plain paper without curl correction are also shown in FIGS. 11(A) to 11(C). Also, the vertical axis is the curl height h (IIll)
, the roll diameter is plotted on the horizontal axis.

FIG. 11(A) shows the rotational force of the arm 26 (1 kgcm) set according to the thermal paper, that is, the switching lever 4
9 shows the results of an experiment in which the sheet material 5 made of thermal paper and the sheet material 5 made of plain paper were curled while being moved to the solid line position in FIG. As is clear from the figure, although the curls of the thermal paper were properly corrected, the curls of the plain paper were not sufficiently corrected.

In addition, the same figure (B) shows a sheet made of thermal paper while the rotational force of the arm 26 is set (1.5 kgc + 1) in accordance with plain paper, that is, while the switching lever 40 is moved to the position shown by the two-dot chain line in Fig. 9. 5 shows the results of an experiment in which a sheet material 5 made of a sheet material 5 and plain paper was curled.

As is clear from the figure, although the curling of plain paper was properly corrected, the curling of thermal paper was excessive and resulted in reverse curling in the opposite direction to the curling.

Moreover, the same figure (C) shows the experimental result of curl correction by switching the switching lever 40. In other words, in the case of thermal paper, the switching lever 40 changes the rotational force of the arm 26 to 1 kgcm.
Then move the switching lever 40 to the solid line position in Fig. 9)
, and in the case of plain paper, the switching lever 40 allows the arm 26 to be
The switching lever 40 sets the rotational force to 1.5 kg cm.
9) to the position indicated by the two-dot chain line in FIG. 9) to correct the curl. As is clear from the figure, curls were properly corrected for both thermal paper and plain paper.

Furthermore, as is clear from FIGS. 11(A) to 11(C), the larger the diameter of the roll 5a is, the smaller the curl height h is, and the smaller the roll diameter is, the smaller the curl height is. When the value of h increases and the roll diameter becomes less than about 40 m5+, curls occur, but such curls can be eliminated.

In this manner, the decurling mechanism A changes the decurling effect depending on the strength of the curl by balancing the tension acting on the sheet 5 with the rotational force of the arm 26, and corrects the curl appropriately.

Further, the arm 26 is biased by a tension spring 35, and the tension force of the tension spring 35 can be switched by a switching lever 40, so that curl correction can be performed appropriately depending on the type, thickness, etc. of the sheet material 5. It is something.

Furthermore, the rotational force of the motor 20 in the mating direction is transmitted to the platen roller 6a, but not to the arm 26. Therefore, since there is no load on the motor 20 to move the arm 26 during recording, the conveyance accuracy is improved. This increases the image quality and enables high-quality recording.

After an image is recorded on the sheet material 5 whose curls have been corrected as described above, it is cut by a counter 7 and discharged by a discharge roller 8.

On the other hand, the tip of the sheet material 5 in the device is placed on the canter 7.
It is transported backward by a distance l from the position to the recording means 6. This is to prevent a blank area from appearing at the leading edge of the sheet during the next recording. Therefore, when the motor 20 is driven in the reverse direction by a predetermined amount, the driving force is applied not only to the platen roller 6a but also to the spring clutch 30, which is locked as described above.
The force is also transmitted to the punch flange 28 and acts to rotate the arm 26 in the direction indicated by the arrow.

At this time, as shown in FIG. 7, a tension force is applied to the arm 26 by a tension spring 35 in a direction that prevents the rotation. For this reason, the driving force of the motor 20 in this embodiment is set to be larger than the arm rotation force caused by the tension force of the tension spring 35 when driving in reverse as described above.

Therefore, when the motor 20 is driven in the reverse direction to reversely feed the sheet material 5 as described above, the rear arm 26 is driven by the driving force.
rotates in the direction indicated by the arrow, separates from the sheet material 5, and returns to the initial position shown by the two-dot chain line in FIG.

Here, the initial position is a position where the other end 30b of the spring clutch 30 is in contact with the stone bar 38, as shown in FIG. 10(C), and a position where the guide shaft 23 does not block the opening of the roll holder 4. That is, a position where the guide shaft 23 does not interfere with the decal shaft 22 when the lid body 2 is opened. In this state, since the guide shaft 23 is separated from the sheet material 5, the sheet material 5 is not curled in the opposite direction even if the recording standby state continues for a long time.

Note that the initial position is regulated by the stopper 38, which eliminates the need to take up an unnecessarily large space for retracting the guide shaft 23, allowing effective use of the space within the main body 1, such as accommodating various motors and sensors. This makes it possible to downsize the main body 1. That is, since the position of the guide shaft 23 also changes depending on the weight of the roll 5a, the initial position of the guide shaft 23 also changes when the sheet material 5 is fed back, but since the initial position is kept constant by the stopper 38, There is no need to take up a large space for retracting the guide shaft 23.

Moreover, when the motor 20 is driven in reverse to reversely feed the sheet material 5 by a distance l, the arm 26 rotates! (Return angle α) is set to an angle at which the arm 26 rotates from the position where it contacts the stopper 36 to the initial position as shown in FIG.

That is, the motor 2 when rewinding the sheet material 5 by the length l
The distance 2 between the platen roller 6a and the cutter 7, the distance 2 between the platen roller 6a and the shaft 25, and the rotation amount of the motor 20 when rotating the arm 26 by the angle α in the direction indicated by the arrow are the same. The rotation ratio, the position of the stopper 36, etc. are set.

Next, the motor driving force required to operate each member will be explained when the motor 20 is driven in forward rotation and when it is driven in reverse.

If the motor output when driving the motor 20 in normal rotation (when conveying the sheet material 5 in the recording direction) is Pl, then
In this case, since the spring clutch 30 is in a free state, the output P1 may be the driving force necessary to rotate the platen roller 6a.

On the other hand, if the motor output when driving the motor 20 in the reverse direction (when conveying the sheet material 5 in the rewinding direction) is P2, the spring clutch 30 is in a locked state in this case, so the output P2 is The driving force necessary to rotate the arm 6a and the driving force necessary to rotate the arm 26 against the tension spring 35 are required, and the driving force is larger than that in the case of normal rotation drive (p+<pg). Is required.

Therefore, if the rated output of the motor 20 is set to P2, the surplus output of the motor 2o (y'!-
Pl) causes vibration, which may cause uneven feeding, noise, etc.

Therefore, in this embodiment, the output when driving the motor 20 in the normal rotation is set to P1, and when driving the motor 20 in the reverse rotation, the output is set to P2, which is larger than that when driving the motor 20 in the normal rotation. This can be easily accomplished by a known method such as increasing the driving current of the motor 20 during reverse rotation compared to normal rotation, or lowering the rotation speed.

As described above, even if the drive current is increased or the rotational speed is set low during reverse drive, the rewinding amount l (for example, 20 open) is sufficiently small, the influence of the temperature rise of the motor 20 during reverse drive or the delay in the reverse feeding time of the sheet material 5 is extremely small.

Further, an arm 26 driven by the motor 20
It is preferable to set the gear ratio etc. so that the rotational speed of the platen roller 6a is the same as or slightly faster than the rotational circumferential speed of the platen roller 6a (the conveyance speed of the sheet material 5). When the material 5 is transported back, the guide shaft 23 quickly retreats from the position shown in FIG. 10(a) or (b) to the initial position shown in FIG. 10(C).

The motor 20 stops after rewinding the sheet material 5 by a predetermined amount i, but at this time the arm 26 is in a tensioned state by the tension spring 35.

The second tensile force is applied to the pulley 33 by arrow f as shown in FIG.
In order to rotate the motor 20 in the direction shown in FIG. act.

For example, the rotation torque for rotating the pulley 33 in the direction of arrow f is 1. (for example, about 1 kgcm+), and if the rotational speed ratio of the motor 20 and clutch gear 29 is 10:1, the rotational torque Tt transmitted to the motor 20 by the rotational force is T+/10 (0.1kgcm). .

Therefore, in this embodiment, in order to prevent the arm 26 from rotating when the motor 20 is stopped, the self-holding torque of the motor 20 (when torque is applied from the outside to the rotor made of permanent magnets, the magnetic force The torque at which the rotor attempts to come to a standstill) is greater than the rotational torque tz transmitted to the motor 20 (for example, 0.2 kgcm).
It is set.

As a result, in the recording apparatus of this embodiment, the arm 26 is held at the initial position indicated by the two-dot chain line in FIGS. 5 and 6 in the recording standby state.

Therefore, when opening the lid 2, such as when replacing the roll 5a, the guide shaft 23 does not interfere with the decal shaft 22, and the lid 2 can be opened smoothly.

Further, in this embodiment, as shown in FIGS. 2 and 9, a micro switch 45 is turned on and off by a switching lever 40.
is provided near the switching lever 40 of the main body l,
The microswitch 45 detects the position of the switching lever 40, that is, whether it is switched to the side where the tensile force of the tension spring 35 is reduced or the side where the tensile force of the tension spring 35 is increased, and the reverse rotation is performed based on this detection result. The strength of the output P2 of the motor 20 during driving can be switched.

That is, when the microswitch 45 is in the OFF state, the tension force of the tension spring 35 is weak and the driving force to rotate the arm 26 is small, so the output P during reverse drive is changed to a small output Pea (P□>P t ),
Furthermore, when the microswitch 45 is in the off state, the tensile force of the tension spring 35 is strong and the driving force to rotate the arm 26 is large, so the output Pz during reverse drive is switched to a large output Pzb (Pzb < Pt-) accordingly. hand,
Efficient output settings can be made.

FIG. 12 shows a block diagram of the control system of the entire recording system B including output control when the platen motor 20 is driven in reverse.
M, 62 is a RAM, and 63 is an interface. The interface 63 is connected to the platen motor 2.
0, a motor drive circuit 64 for the ink sheet motor 50c and the discharge motor 8a is connected to a print head drive circuit 65 for the print head 6b. Further, the microswitch 45 is connected to the interface 63.

The contents of the flowchart shown in FIG. 13 are stored in the ROM 61, and the motor drive circuit 64 and the recording head drive circuit 65 are controlled by the CPU 60 based on the contents of this flowchart. Also, when a signal is input manually from the microsinch 45 via the interface 63,
The motor drive circuit 64 is controlled by the CPU 60, and the output P2 when the platen motor 20 is driven in reverse is the output Pza.
Alternatively, it can be switched to output P2b.

That is, when the recording system B operates, the platen motor 20 first rotates forward in step SIO, and then the ink sheet motor 50c rotates in step Sll.

Next, in step S12, the recording head 6C is energized for recording, and in step S13, it is determined whether or not recording of page 1 has been completed.If YES, in step S14, when the trailing edge of the image moves to the cutter 7 position, the platen is motor 20
, the ink sheet motor 50c stops, and then in step 315 the cutter 7 operates to cut the sheet material 5.

Next, in step S16, it is determined whether the microswitch 45 is on or off, and if it is on (YES), the platen motor 20 is reversely driven with a small output Pem in step 517, so that the leading edge of the sheet material 5 is It is fed backward from the cutter 7 position to the recording means 6 position. Also,
If the microswitch 45 is off (No), a large output P is generated in step 31B. Then, the platen motor 20 is driven in the reverse direction, and the leading edge of the sheet material 5 is transported backward from the cutter 7 position to the recording means 6 position.

Next, in step S19, it is determined whether or not the next page is to be recorded. If YES, the process returns to step SIO to repeat the same operation; if NO, the operation of recording system B ends.

Since the device of this embodiment is configured as described above, it is possible to correct the curl appropriately depending on the strength of the curl, the type and thickness of the sheet material 5, etc. Since the load is only the load for rotating the platen roller 6a, the sheet can be conveyed accurately, and furthermore, the roll 5a can be easily replaced.

[Second example]

In the first embodiment described above, an example was shown in which the guide shaft 23 was movable with respect to the decal shaft 22, but as a second embodiment, an embodiment in which the decal shaft 22 was configured to be movable is shown in FIG. .

Incidentally, the same parts and parts having the same functions as those in the first embodiment are given the same reference numerals, and the explanation thereof will be omitted.

In FIG. 14, the guide shaft 23 is rotatably attached to a support member 70 of the device main body l.

- direction, the decal shaft 22 is rotatably attached to an arm 72 fixed to a shaft 71 rotatably attached to the lid body 2, and the sheet material 5 is curled by rotation of the arm 72 in the direction of arrow g. is corrected, and the correction is canceled by rotation in the -g direction.

A clutch gear 74 having a torque limiter 73 fixed to the center thereof is rotatably provided at one end of the shaft 71. The torque limiter 73 transmits the rotational force (rotational torque) of the clutch gear 74 to the shaft 71 in response to a signal from a control section (not shown). A gear 76 fixed to a motor 75 meshes with the clutch gear 74 so that the driving force of the motor 75 is transmitted to the clutch gear 74.

Here, the value of the transmission torque of the torque limiter 73 can be arbitrarily set by an input operation from an operation section (not shown). For example, from 200gcm to 2000
It is possible to set a value in the range of gc+a.

Further, a control section (not shown) of the torque limiter 73 is configured to control the torque limiter 73 to operate at a set transmission torque value.

In the above configuration, during recording, the lid body 2 is closed, the motor 20 is driven to rotate the platen roller 6a, and the sheet material 5 is conveyed in the direction of arrow e, and the recording head 6b is driven in accordance with both signals. By doing so, an image is formed on the sheet 4 material 5. At this time, at the same time as the motor 20 is driven, the motor 75
When the decal shaft 22 is rotated in the direction of arrow i and the arm 72 is rotated in the direction of arrow g, the decal shaft 22 comes into contact with the sheet material 5,
Then, the arm 72 stops at a position where the rotational force of the arm 72 (transmitted torque of the torque limiter 73) and the tension of the sheet material 5 are balanced, and the sheet material 5 is bent by the decal shaft 22 in the opposite direction to the curling direction. Curls are corrected by this.

Here, when the curl correction effect is small and the curl height h is large, input is made to the operation unit so that the value of the transmitted torque becomes large (increasing the curl correction effect). Also,
If the curl straightening effect is too large, the operating section is manually operated (reducing the curl correcting effect) so that the value of the transmitted torque is reduced.

By doing so, appropriate curl correction can be performed depending on the type, thickness, etc. of the sheet material 5.

When recording is completed, the motor 20 is driven in reverse to transport the leading edge of the sheet material 5 from the cutter 7 to the position of the platen roller 6a. Further, the motor 75 is rotated in the direction of arrow -1 to rotate the arm 72 in the direction of arrow -g, thereby canceling the curl correction.

Note that if the output value of the motor 75 is also controlled to be varied in response to the input from the operating section of the driver controller 73, the driving efficiency will be improved. Furthermore, if the arm 72 is rotated by the motor 20 without using the motor 75, motor efficiency can be improved.

[Other Examples]

In the first embodiment described above, the guide shaft 23 is attached to the decal shirt) 22FJi:7-4 in the second embodiment, and is configured to be moved by rotating this arm. There is no need to limit it to this; for example, as another configuration, the guide shaft 23 or decal shaft 22 may be configured to move in parallel along a rack or rail, or may be moved by being pushed up with a cam etc. good.

Further, both the decal shaft 22 and the guide shaft 23 may be made movable by combining the first embodiment and the second embodiment.

Further, the decal shaft 22 and the guide shaft 23 may be fixed to the mounting member 24 and the arm 26, respectively, and furthermore, instead of a metal shaft, they may be formed of a metal plate or the like bent into a curved surface with a predetermined oil ratio radius. .

Further, although the first embodiment uses a spring clutch 30 to transmit the driving force of the motor to the decal shaft 22, the spring clutch 30 is not limited thereto, and may be, for example, a roller type knee torque clutch or a roller type clutch.

It is also possible to use a method such as . Furthermore, it is possible to use an electromagnetic clutch or the like that can switch between power transmission and release without being limited to the direction of rotation by a signal from the control section.

Further, in the first embodiment, the motor 20 that drives the platen roller 6a is used as a drive source for moving the guide shaft 23, but it is natural that these may be driven by separate motors.

Further, the driving source is not limited to a motor, and for example, a plunger or the like may be used.

Furthermore, decal shirt 22 or guide shirt)・23
Although a tension spring was used in the above-described embodiment as a biasing means for biasing the decal in a direction that increases the decal effect, the present invention need not be limited to this. For example, torsion coil springs,
In addition to springs such as compression springs and mainsprings, we also use cylinders such as air cylinders and oil cylinders, or magnets.
You may also use

In addition, in the first embodiment, the curl correction effect is large on plain paper;
Although the setting is made so that the size becomes smaller using thermal paper, the setting may be made in the opposite way. In addition to the type and thickness of the sheet material 5, the switching lever 40 is switched depending on the time since it has been rolled, the core diameter of the roll 5a, temperature, humidity, etc. to change the magnitude of the curl correction effect. In addition, although the first embodiment shows a case where the curl correction action is switched to two stages using the switching lever -40, the present invention is not limited to this, and the structure may be configured such that the curl correction action is switched steplessly. . In this case, a plurality of racks 42 for fixing the other end of the tension spring 35 may be provided on the main body 1 side, and the position at which the end of the tension spring 35 is fixed may be changed.

<Effects of the Invention> As described above, the present invention is capable of switching the urging force that urges the moving means for moving at least one of the guide member and the decal member in the direction of increasing the bending of the sheet material to a larger or smaller amount using a switching means. Therefore, the curl correction effect can be easily adjusted, and curls can be appropriately corrected depending on the thickness, type, etc. of the sheet material.

[Brief explanation of drawings]

1 and 2 are perspective explanatory views of a first embodiment in which the present invention is applied to a recording system of a facsimile machine, FIG. 3 is an explanatory overall cross-sectional view of the facsimile machine, and FIG. 4 is an explanation of curling of sheet material. Fig. 5 is an explanatory diagram of a state in which recording is performed with a large diameter sheet roll loaded, Fig. 6 is an explanatory diagram of a state in which recording is performed with a small diameter sheet roll, and Figs. 7 and 8 are explanatory diagrams of the configuration of the decurling mechanism. , Fig. 9 is an explanatory diagram explaining the action of the switching lever, Figs. 10 (A) to (C) are state explanatory diagrams explaining the movement position of the guide shaft, and Figs. 11 (^) to (C).
12 is a block diagram of the control system, FIG. 13 is a flowchart showing control details, and FIG. 14 is an explanatory diagram of the second embodiment. , FIG. 15, and FIG. 16 are explanatory diagrams of the prior art. A is the decal mechanism, B is the recording system, C is the document reading system,
1 is the device body, 2 is the lid, 3 is the shaft, 4 is the roll holder, 5 is the sheet material, 5a is the sheet roll, 5b is the winding core, 6
8 is a recording means, 6a is a platen roller, 6b is a recording head, 6b is a heating element, 6c is a shaft, 6d is a compression spring, 7 is a cutter, 7a is a fixed blade, 7b is a driving blade, 7c is a shaft, 8
is a discharge roller, 9 is a stacker, 1O is a document placement table, 11
is a document, 12a is a pre-(l! transport roller, 12b is a pressure contact member, 13a is a separation roller, 13b is a pressure contact member, 14a,
14b, 15a15b are conveyance rollers, 16 is a light source, 17
is a ξ roller, 18 is a lens, 19 is a charging conversion element, 20 is a motor, 21a to 21d are gears, 22 is a decal shaft, 23 is a guide shaft, 24 is a mounting member, 24a
is a flat plate, 24b is a bracket, 25 is a shaft, 26 is an arm, 27 is a bearing, 28 is a clutch flange, 28a is a cylindrical part, 28b is a flange part, 29 is a craft gear, 29a is a cylindrical part, 29b is a gear part, 30 is a Spring clutch, 31.32
is a rotation bottle, 33 is a pulley, 33a is a groove, 34a, 34
b is a hook, 35 is a tension spring, 36 is a stopper, 37
is a guide, 38 is a support member, 39 is a shaft, 40 is a switching lever, 41 is a bottle, 42, 43 is a stopper, 45 is a micro switch, 50 is an ink sheet, 50a is a supply roll, 50b is a take-up roll ,60 is CPU, ,,6
1 is ROM, 62 is RAM, 63 is ink-face,
70 is a support member, 72 is an arm, and 73 is a dowel client.

Claims (8)

[Claims] (1) A conveying means for conveying the sheet material, a guide member for guiding the conveyance of the sheet material, a decal member for bending and guiding the conveyed sheet material, the guide member and the decal member a moving means for moving at least one of the above, a biasing means for biasing the moving means in a direction in which the bending of the sheet material increases, and a switching means for switching the biasing force of the biasing means. Has a decal mechanism. (2) The decurling mechanism according to claim 1, wherein a drive source for the conveying means and a drive source for the moving means are the same. (3) The decurling mechanism according to claim 2, wherein the output of the drive source is configured to be varied by the switching means. (4) The decurling mechanism according to claim 1, wherein the device main body and the lid are configured to be openable and closable, the decal member is provided on the lid, and a guide member is provided on the device main body. (5) The decurling mechanism according to claim 1, wherein the self-holding force of the drive source for operating the moving means is set to be larger than the urging force applied to the moving means by the urging means. (6) The decurling mechanism according to claim 1, wherein the moving force of the moving means is set to be larger than the urging force of the urging means of the moving means. (7) A recording device comprising: the decurling mechanism according to claim (1); and recording means for recording an image on a sheet material conveyed by the conveyance means. (8) A cutter is provided downstream of the recording means in the sheet material conveying direction, and the driving source of the conveying means for conveying the sheet material and the driving source of the moving means are configured to be the same, and from the cutter. Claim characterized in that the amount of rotation of the drive source required to reverse feed the sheet material to the recording means and the amount of rotation of the drive source required to return the moving means to the initial position are set to be substantially the same. (7) Recording device as described.