JPH04260564A - Decurl mechanism - Google Patents

Abstract

PURPOSE:To miniaturize a decurl mechanism by providing a moving means for moving one of a decurl member and a sheet guide member so as to urge the moving means in a sheet curve increasing direction, and by controlling the movement of the moving means in a curve decreasing direction. CONSTITUTION:A sheet 55a is conveyed in the direction (e) by rotation of a platen roller 56a in the direction of the arrow (a). In synchronization with the rotation of the platen roller 56a, a clutch flange 10 is rotated integrally with a clutch-gear 8 until a recess 10e makes contact with a locking pawl 16. When the recess 10e makes contact with the locking pawl 16, a spring clutch 12 becomes free so that the clutch gear 8 races with respect to the clutch flange 10. Meanwhile, a shaft 4 rotates an arm 2 in the direction (-b) by an urging force in the direction (f) so as to move a guide shaft 18 which is then stopped balancing with a tension force of the sheet 55a. With this arrangement, the sheet 55a is wound onto the guide shaft 18 in the curling direction, and then is curved in a direction reverse to the curling by a decurl shaft 72, thereby it is possible to remove the curling.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a decurling mechanism for correcting curls in a sheet material wound into a roll.

0002

2. Description of the Related Art Today, office equipment such as facsimile machines and printers are widely used, and the recording system of these devices generally uses a roll sheet in which a long recording sheet is wound around a core. Since this sheet material is wound into a roll, it tends to be curled (hereinafter referred to as "curl"), and curled sheet materials tend 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.

FIGS. 8 to 12 show a structure of the decurling mechanism proposed by the applicant in Japanese Patent Application No. 1-192632. The structure and operation of this decurling mechanism will be explained based on FIGS. 8 to 12. First, in FIG. 9, the roll holder 54 is formed to have an open top, and this is connected to the recording system main body 51.
It is located at the back of the. A sheet roll 55a is loaded into the roll holder 54, and the outer peripheral surface of the roll 55a and the inner surface of the holder 54 come into contact with each other, thereby creating frictional resistance. That is, when the sheet material 55 is pulled out, when the roll 55a has a large diameter and is heavy, a large frictional resistance is generated, and the sheet material 55 is pulled out and the roll 55a is heavy.
As the weight of a decreases, the frictional resistance also decreases. This frictional resistance has the effect of applying tension to the sheet material 55 when the sheet material 55 is drawn out, and the sheet material 5 that is drawn out is proportional to the magnitude of the frictional resistance.
The tension applied to 5 also changes.

The recording means 56 for recording a predetermined image on the sheet material 55 is composed of a platen roller 56a and a recording head 56b. The platen roller 56a 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 configured to be driven by a motor 70 serving as a drive source. There is. That is, as shown in FIG. 8, the rotational force of the motor 70 is transmitted from a gear 71a fixed to the motor shaft to a gear 71c fixed to the roll shaft of the platen roller 56a via an intermediate gear 71b.
The platen roller 56a rotates. The sheet material 55 is conveyed by the rotation of the platen roller 56a, and the platen roller 56a also serves as a means for conveying the sheet material 55.

The recording head 56b forms an image on the sheet material 55 by heating the sheet material 55 in accordance with an image signal, and is configured to press the platen roller 56a through the sheet material 55. ing. Specifically, it is rotatably attached to the lid 52 by a shaft 56c, and is configured to press the platen roller 56a by a compression spring 56d when the lid 52 is closed. Therefore, when the platen roller 56a rotates with the sheet material 55 inserted between the platen roller 56a and the recording head 56b, the sheet material 55 is conveyed.

Next, the cutter 7 has a fixed blade 57a and a driving blade 57.
A rotary cutter consisting of b is used. Specifically, the fixed blade 57a is fixed to the main body 51, and the driven blade 57a is fixed to the main body 51.
b is attached to be rotatable around a shaft 57c, and when the driving blade 57b is rotated by the driving means, the fixed blade 57
The sheet material 55 is cut by rubbing against the a.

[0007] Here, since the sheet material 55 is wound around the winding core 55b, it curls when it is pulled out from the sheet roll 55a, but this curl differs depending on the diameter of the roll 55a. The curl is corrected when the sheet material 55 passes through a decurling mechanism. That is, the position of the guide shaft 73 serving as a guide member is configured to be movable with respect to the decal shaft 72 serving as a decurling member, and the sheet material 55 is moved between the two shafts 72,
The curl is corrected by being bent in a direction opposite to the curl direction when being guided by the guide 73.

The guide shaft 73 is biased against the sheet material 55 by a biasing means, which will be described later, and can be loaded with a large-diameter roll 55a as shown in FIG. 9, and with a small-diameter roll 55a as shown in FIG. The decal effects are now different. Here, the configuration of the decurling mechanism will be specifically explained. The decal shaft 72 is rotatably attached to a mounting member 74 fixed to the lid body 72 as shown in FIG. The mounting member 74 is made of sheet material 55
It is composed of a flat plate 74a that serves as a guide, and brackets 74b formed upright at both ends of the flat plate 74a, and the distance between the brackets 74b is larger than the width of the sheet material 55, and supports both ends of a guide shaft 73, which will be described later. It is formed smaller than the spacing between the arms. A decal shaft 72 is rotatably attached to the bracket 74b.

This decal shaft 72 is shown in FIGS. 9 and 1.
0, when the lid body 52 is closed, its position with respect to the main body 51 is always constant, and the position at this time is on the upstream side in the conveying direction of the sheet material 55 with respect to the platen roller 56a, and 55 to the platen roller 56a does not become too large.

Further, on the main body 51 facing the decal shaft 72, there is a sheet material 5 pulled out from the roll 55a.
A guide 87 is provided for guiding the roller 5 to the platen roller 56a. One end of this guide 87 extends to the vicinity of the platen roller 56a, and the other end is configured to be integrated with the roll holder 54.

On the other hand, the guide shaft 73 is configured to be movable relative to the decal shaft 72 by a moving means. As shown in the perspective explanatory view in FIG. 11 and the cross-sectional explanatory view in FIG. 73 is rotatably attached, and when the shaft 75 rotates, the arm 76 rotates integrally, thereby making the guide shaft 73 movable relative to the decal shaft 72.

The shaft 75 is rotatably attached to the main body 51 via a bearing 77, and a clutch flange 78, a clutch gear 79, and a spring clutch 80 are attached to one end of the shaft, so that rotational force in one direction is applied to the shaft 75. It is configured to be transmitted. The clutch flange 78 has a cylindrical portion 7
8a and a collar portion 78b, and is attached to the shaft 75 by a rotation pin 81 so as to rotate together with the shaft 75 in the same direction.

The clutch gear 79 is composed of a cylindrical portion 79a and a gear portion 79b, the inner diameter of the hole through which the shaft 75 is inserted is slightly larger than the outer diameter of the shaft 75, and the clutch gear 79 is rotatably attached to the shaft 75. It is being The spring clutch 80 is formed by winding a spring steel wire, a spring steel strip, a plastic wire, etc. into a coil shape, and
8 and the clutch gear 79, and one end thereof is locked to the flange 78b of the clutch flange 78.

The spring clutch 80 is connected to a clutch gear 79.
The rotational force is transmitted to the clutch flange 78 in only one direction, and not in the other direction. That is, when the clutch gear 79 rotates in the direction of arrow a in FIG. 11, the spring clutch 80 is loosened and becomes free, and no rotational force is transmitted to the clutch flange 78. On the other hand, when the clutch gear 79 rotates in the opposite direction of the arrow -a (hereinafter, the minus sign indicates the opposite direction of the arrow), the spring clutch 80 tightens the cylindrical parts 78a and 79a to be in a locked state, and the clutch flange 78 Rotational force is transmitted to move the guide shaft 73 in the direction of arrow b.

The drive source for rotating the clutch gear 79 is the same as the drive source for rotating the platen roller 56a, and is driven by the motor 70. That is, as shown in FIG. 8, the driving force of the motor 70 is transmitted to the platen roller 56a via the gears 71a to 71c as described above, but the driving force of the motor 70 is transmitted to the platen roller 56a through the gears 71a to 71c.
is the gear portion 7 of the clutch gear 79 via the intermediate gear 71d.
It meshes with 9b.

Therefore, as shown in FIG. 8, when the motor 70 rotates forward in the direction of arrow c, the platen roller 56a moves in the direction of arrow d.
The clutch gear 79 rotates in the direction of arrow a. That is, when the platen roller 56a rotates in a direction to pull out the sheet material 55 in the direction of arrow e, the spring clutch 80 is in a free state. Further, when the motor 70 rotates in the opposite direction of the arrow -c, the platen roller 56a rotates in the direction of feeding the sheet material 55 in the reverse direction, and at this time, the clutch gear 79 rotates in the direction of the arrow -a, causing the spring clutch 80 to rotate in the direction of the arrow -a.
is in a locked state and transmits the rotational force that rotates the guide shaft 73 in the direction of arrow b in FIG.

Next, the guide shaft 73 is attached to the sheet material 5.
The configuration of the biasing means that biases the device so as to be balanced with the tension of No. 5 will be explained. As shown in FIGS. 11 and 12, a pulley 83 is fixed to the other end of the shaft 75 by a rotation pin 82. A groove 83a is formed on the circumferential surface of the pulley 83, and a hook 84a is provided protrudingly at a predetermined position, between this hook 84a and a hook (not shown) protrudingly provided at a predetermined position of the main body 51. A tension spring 85 is attached under tension. That is, the pulley 83 is always urged in the direction of arrow f in FIG. 11 (the direction in which the decurling effect by the guide shaft 73 is increased) by the tensile force of the tension spring 85.

A stopper 86 is also provided at a predetermined position on the main body 51 within the rotation range of the arm 76. This stopper 86 comes into contact with the arm 76 when it rotates in the direction of arrow -b in FIG. 11, and limits the amount of rotation of the arm 76 and sets the maximum amount of wrapping of the sheet material 55 around the decal shaft 72. It is something to do. Next, we will explain the curl correction operation when recording using a recording system having a decurling mechanism configured as described above, when the roll diameter is large as shown in FIG. 9, and when the roll diameter is small as shown in FIG. I will mainly explain.

First, open the lid 52 and remove the sheet roll 55.
A is loaded into the roll holder 54, and the leading edge of the sheet is pulled out to the platen roller 56a and set. At this time, as shown in FIG. 8, since the decal shaft 72 is attached to the lid 52 and the guide shaft 73 is attached to the main body 51, when the lid 52 is opened, both shafts 72
, 73 are widely spaced apart, and the sheet material 55 can be easily set.

Next, when a recording start signal is input with the lid 52 closed, the motor 70 rotates forward and the platen roller 5
6a rotates in the direction of arrow d, and the sheet material 55 is conveyed in the direction of arrow e. In synchronization with this conveyance, the heating elements of the recording head 56b selectively generate heat to perform predetermined recording on the sheet material 55. Then, when the sheet material 55 is conveyed, the decurling mechanism operates to correct the curl of the sheet material 55.

That is, the forward rotation driving force of the motor 70 is also transmitted to the clutch gear 79, but as described above, the spring clutch 80 is in a free state and the clutch gear 79 is idle relative to the clutch flange 78. On the other hand, the shaft 75
As shown in FIG. 11, since a biasing force in the direction of arrow f is applied due to the tensile force of the tension spring 85, the arm 76 rotates in the direction of arrow -b and the guide shaft 73 moves.
It stops at a position balanced with the tension of the sheet material 55.

[0022] As a result, the conveyance path of the sheet material 55 starts from the sheet roll 55a and wraps around the guide shaft 73 in the curling direction, then bends at the decal shaft 72 and wraps around the shaft 72 in the opposite direction to the curling direction. This wrapping around the decal shaft 72 corrects the curl of the sheet material 55. The tension applied to the sheet material 55 being conveyed here is caused by contact friction between the roll holder 54 and the roll 55a loaded on this holder 54. That is, as shown in FIG. 9, if the weight of the roll 55a is G1 and the tension acting on the sheet material 55 is F1, then the guide shaft 73
A tension F1 acts along the sheet material 55 before and after. Further, the amount of wrapping of the sheet material 55 around the guide shaft 73 increases, and accordingly, the effect on the rotational force of the arm 76 (rotational torque of the pulley 83 due to the tensile force of the tension spring 85) against the resultant force of the tension F1 increases. do. The arm 76 then stops at a position where the resultant force and the rotational force of the arm 76 are balanced.

As shown in FIG. 9, when the roll system is large, the wrapping angle at which the sheet material 55 wraps around the decal shaft 72 when the tension F1 on the sheet material 55 and the rotational force of the arm 76 are balanced is θ1. Then, it is guided to the platen roller 56a. On the other hand, as shown in FIG. 10, when the diameter of the roll 55a becomes smaller, the roll weight G2 also becomes smaller (G2<G1), and the tension F2 acting on the sheet material 55 also becomes smaller (F2<F1). Therefore, the arm 76 rotates further in the direction of arrow -b than when the roll diameter is large. If the rotational force of the arm 76 and the resistance force are balanced, the arm 76 will stop at that position, but if the amount of rotation of the arm 76 is greater, it will stop at the position where it contacts the stopper 86. . At this time, the sheet material 55
is the wrapping angle θ2 that wraps around the decal shaft 72,
The winding angle θ1 is smaller than the wrapping angle θ1 when the roll diameter is large.

Therefore, when the diameter of the roll 55a is large, the amount of sheet material wrapped around the decal shaft 72 is small;
As the roll diameter becomes smaller and the curl becomes stronger, the amount of wrapping becomes larger. As the amount of wrapping increases, the sheet material 55 is bent in the direction opposite to the curl, so that the curl correction effect increases. That is, as the roll diameter becomes smaller and the curl becomes stronger, the curl correction effect becomes larger.

After recording an image on the sheet material 55 whose curls have been corrected as described above, the sheet material 55 is cut by the cutter 5.
It is cut at 7. On the other hand, the leading end of the sheet material 55 in the apparatus is transported backward by a distance l from the position of the cutter 57 to the recording means 56. This is to prevent blank areas from occurring at the leading edge of the sheet during the next recording. Therefore, the motor 70
When the platen roller 56a is driven reversely by a predetermined amount, the driving force is transmitted not only to the platen roller 56a but also to the clutch flange 78 as the spring clutch 80 becomes locked as described above.
A force is applied to rotate the arm 76 in the direction of arrow b.

Therefore, when the motor 70 is driven in reverse in order to reversely feed the sheet material 55 as described above, the arm 76 rotates in the direction of arrow b due to the driving force and separates from the sheet material 55, as shown in FIG. Return to the initial position shown by the dotted chain line. Note that the initial position here is a position where the guide shaft 73 does not block the opening of the roll holder 54, and since the guide shaft 73 is separated from the sheet material 55 when the lid body 52 is opened, it is not possible to wait for recording. Even if the condition continues for a long time, the sheet material 55 will not be curled in the opposite direction.

It should be noted that the amount by which the arm 76 rotates (return angle α) when the motor 70 is driven in reverse to reversely feed the sheet material 55 by a distance L is determined by the rotation angle of the arm 76 as shown in FIG.
The rotation angle is set at such an angle that the rotor rotates from the position where it contacts the stopper 86 to the initial position. That is, the amount of rotation of the motor 70 when rewinding the sheet material 55 by the length L, and the amount of rotation of the arm 76
The distance L between the platen roller 56a and the cutter 57, and the distance L between the platen roller 56a and the shaft 75 are set so that the amount of rotation of the motor 70 when rotating the platen roller 56a by an angle α in the direction of arrow b is the same.
The rotation ratio, the position of the stopper 86, etc. are shown.

The above is the structure and operation of the conventional decurling mechanism.

[0029]

However, in the above-mentioned conventional example, the motor 70 reverses and the sheet material 55
When the sheet material 55 is rewound, the rotation angle of the arm 76 is always a constant value α, so the position of the arm 76 after the sheet material 55 is rewound is as shown by the two-dot chain line in FIGS. 9 and 10. It changes depending on the size of the diameter of the roll 55a (remaining amount of sheet material). In terms of the position where the guide shaft 73 does not block the opening of the roll holder 54, the arm 76 is in a position similar to that shown in FIG.
It is sufficient to move the arm 76 to the position shown by the two-dot chain line in FIG. A space sufficient to accommodate the position indicated by the two-dot chain line is required. Therefore, there is a problem in that a wasted space is created in the storage space of the arm 76, which becomes an obstacle to miniaturization of a facsimile machine or the like in which a decal mechanism is mounted.

[0030] Therefore, the present invention has been made in view of the above-mentioned problems, and its object is to provide a decal mechanism that does not waste storage space for the arm and allows for miniaturization of the device. be.

[0031]

[Means for Solving the Problems] In order to solve the above-mentioned problems and achieve the objects, the decal mechanism of the present invention includes a conveying means for conveying a sheet material, and a means for guiding the conveyance of the sheet material. a guide member, 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 a decal member for bending and guiding the sheet material to be conveyed; The present invention is characterized by comprising a biasing means for biasing the moving means, and a control means for controlling the amount of movement of the moving means in a direction in which the sheet material is not bent.

Furthermore, the decurling mechanism according to the present invention is characterized in that 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. . Further, in the decurling mechanism according to the present invention, 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.

Furthermore, the decurling mechanism according to the present invention is characterized in that the moving force of the moving means is set to be larger than the urging force of the urging means of the moving means.

[0034]

[Operation] As described above, the decal mechanism according to the present invention is constructed so that the tension applied to the sheet material,
It becomes possible to control the moving means, which is stopped in a state where the urging force of the urging means is balanced, to return to a constant position in the direction in which the sheet material does not bend, regardless of its stopping position, and the movement It is possible to eliminate waste of storage space for means.

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

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. This makes it possible to avoid unnecessarily decurling the sheet material while it is waiting for transportation.

[0037]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings. In addition, one example is as follows.
Since the configuration of many of its parts is the same as that of the conventional example, the same parts as those of the conventional example are given the same reference numerals, and the explanation thereof will be omitted. First, FIGS. 1 and 2 correspond to the parts shown in FIGS. 9 and 10 of the conventional example, and it is in this part that one embodiment differs from the conventional example. Since other parts are similar to the conventional example, the configuration of one embodiment will be explained with reference to FIGS. 1 and 2.

In FIG. 1, a shaft 4, which is the center of rotation of the arm 2, is rotatably attached to the main body 51 via a bearing 6, and a clutch gear 8, a clutch flange 10, and a spring are attached to one end of the shaft. A clutch 12 is installed. The clutch gear 8 consists of a cylindrical part 8a and a gear part 8b,
The inner diameter of the hole through which the shaft 4 is inserted is slightly larger than the outer diameter of the shaft 4, and the hole is rotatably attached to the shaft 4, and a flange portion is formed around the end of the hole. 4
The position in the thrust direction is determined by contacting a.

1 and 2, the clutch flange 10 is composed of a cylindrical portion 10a and a flange portion 10b, and has a D-shaped hole 10c formed in its center. A similarly D-shaped cut portion 4b formed at the tip of the shaft 4 is inserted into the hole 10c, and the shaft 4 is shown in FIG. As shown, for the clutch flange 10,
It is relatively rotatable by an angle β. and axis 4
A retaining ring 14 is attached to the end of the shaft 4, and the clutch gear 8 and clutch flange 10 are attached to the flange portion 4a of the shaft 4.
It is held on the shaft 4 by being sandwiched between a retaining ring 14 and a retaining ring 14. Further, a convex portion 10e is formed on the clutch flange 10, and this convex portion 10e is connected to a locking pawl 1 fixed to the main body 51.
6, the clutch flange 10 moves as shown in FIG.
The rotation in the clockwise direction is restricted.

On the other hand, the spring clutch 12 is formed by winding a spring steel wire, a spring steel strip, a plastic wire, or the like into a coil, and includes a clutch flange 10 and a clutch gear 8.
It is wound around the outer periphery of both cylindrical parts while slightly tightening both cylindrical parts, and one end thereof is locked to the flange part 10b of the clutch flange 10. This spring clutch 12 transmits the rotational force of the clutch gear 8 to the clutch flange 10 in only one direction, and not in the other direction. That is, when the clutch gear 8 rotates in the direction of arrow a in FIG. 2, the spring clutch 12 is loosened and becomes free, and no rotational force is transmitted to the clutch flange 10. However, even when the clutch gear 8 is rotated in the direction of the arrow a, the convex portion 10e of the clutch flange 10
Unless the rotation is restrained by contacting the locking pawl 16,
The clutch flange 10 rotates together with the clutch gear 8 due to the tightening force of the spring clutch 12 on the cylindrical portion 10a.

One clutch gear 8 is indicated by the arrow -a opposite to the above.
When the spring clutch 12 is rotated in the direction shown in FIG. . The drive source for rotating the clutch gear 8 is exactly the same as the conventional example as shown in FIG. 3, and is driven by the same motor 70 as the drive source for rotating the platen roller 56a. The driving force of the motor 70 is transmitted through the gears 71a to 7 as described above.
1c to the platen roller 56a, and is transmitted from the gear 71c attached to the platen roller shaft to the intermediate gear 7.
1d to the clutch gear 8.

Therefore, as shown in FIG. 3, when the motor 70 rotates forward in the direction of arrow c, the platen roller 56a moves in the direction of arrow d.
The clutch gear 8 rotates in the direction of arrow a. That is, the platen roller 56a moves the sheet material 55 in the direction of the arrow e.
When rotating in the direction of pulling out, in Fig. 2,
Initially, the clutch flange 10 rotates together with the clutch gear 8 in the direction of arrow a, and the convex portion 1 of the clutch flange 10
When Oe comes into contact with the locking pawl 16, the clutch flange 10 stops rotating and the spring clutch 12 becomes free.

Further, when the motor 70 reversely rotates in the direction of the arrow -c opposite to the above, the platen roller 56a moves the sheet material 55
At this time, the clutch gear 8 rotates in the direction of the arrow -a, the spring clutch 12 becomes locked, and the rotational force that rotates the clutch flange 10 in the direction of the arrow b in FIG. 2 is transmitted. Next, the guide shaft 18
The structure of the urging means for urging the sheet material 55 so as to be balanced with the tension of the sheet material 55 will be explained.

[0044] This biasing means is also exactly the same as the conventional example,
As shown in FIGS. 1 and 2, a pulley 2 is attached to the other end of the shaft 4.
0 is fixed to the pulley 20, and by the tensile force of the tension spring 22 attached to the hook 20b protruding from the pulley 20, the pulley 20 moves in the direction of the arrow f in FIG. ) is always energized.

A stopper 86 is provided at a predetermined position on the main body 51 in the rotation range of the arm 2. This is to set the maximum value of the amount of winding. This is also the same as the conventional example. Next, we will explain the curl correction operation when recording using a recording system having a decurling mechanism configured as described above, when the roll diameter is large as shown in FIG. 5, and when the roll diameter is small as shown in FIG. I will mainly explain.

First, open the lid 52 and remove the sheet roll 55.
A is loaded into the roll holder 54, and the leading edge of the sheet is pulled out to the platen roller 56a and set. At this time, as shown in FIG. 3, since the decal shaft 72 is attached to the lid 52 and the guide shaft 18 is attached to the main body 1, when the lid 52 is opened, both shafts 72,
18 are widely spaced apart, and the sheet material 55 can be easily set.

Next, when a recording start signal is input with the lid 52 closed, the motor 70 rotates forward and the platen roller 5
6a rotates in the direction of arrow d, and the sheet material 55 is conveyed in the direction of arrow e. In synchronization with this conveyance, the heating elements of the recording head 56b selectively generate heat to perform predetermined recording on the sheet material 55. Then, when the sheet material 55 is conveyed, the decurling mechanism operates to correct the curl of the sheet material 55.

That is, the forward rotation driving force of the motor 70 is also transmitted to the clutch gear 79, but as described above, the clutch flange 10 rotates together with the clutch gear 8 until the protrusion 10e abuts the locking pawl 16. However, after the protrusion 10e contacts the locking pawl 16, the spring clutch 12 becomes free and the clutch gear 8 rotates idly relative to the clutch flange 10. 16.

On the other hand, as shown in FIG. 2, a biasing force in the direction of the arrow f is applied to the shaft 4 due to the tensile force of the tension spring 35, so that the arm 2 rotates in the direction of the arrow -b and the guide shaft 18 moves and stops at a position balanced with the tension of the sheet material 55. As a result, the conveyance path of the sheet material 55 starts from the sheet roll 55a and wraps around the guide shaft 18 in the curling direction, then bends at the decal shaft 72 and wraps around the shaft 72 in the opposite direction to the curling direction. This wrapping around the decal shaft 72 corrects the curl of the sheet material 55.

As shown in FIG. 5, when the roll system is large, the tension on the sheet material 55 and the arm 2
The wrapping angle at which the sheet material 55 wraps around the decal shaft 72 is θ1 when the rotational force of the sheet material 55 is balanced with the rotational force of the decal shaft 72, and then the sheet material 55 is guided to the platen roller 56a. At this time, the rotational positional relationship between the cut portion 4b of the shaft 4 and the hole portion 10c of the clutch flange 10 is as shown in FIG. 4(a).

On the other hand, as shown in FIG. 6, when the diameter of the roll 55a becomes smaller, the tension acting on the sheet material 55 also becomes smaller, so that the arm 2 rotates further in the direction of arrow -b than when the roll diameter is large. . When the rotational force of the arm 2 and the resistance force are balanced, the arm 2 stops at that position, but when the amount of rotation of the arm 2 is greater, it stops at the position where it abuts against the stopper 86. At this time, the sheet material 55 wraps around the decal shaft 72 at a wrapping angle θ2, which is smaller than the wrapping angle θ1 when the roll diameter is large. At this time, the cut portion 4b of the shaft 4
The positional relationship between the hole 10c of the clutch flange 10 and the hole 10c of the clutch flange 10 is shown in FIG.
It is as shown in (b).

After an image is recorded on the sheet material 55 whose curls have been corrected in this manner, the sheet material 55 is cut by a cutter 57. On the other hand, the sheet material 5 inside the device
5 moves the tip backward by a distance L from the position of the cutter 57 to the recording means 56. Therefore, when the motor 70 is driven in the reverse direction by a predetermined amount, the driving force is transmitted not only to the platen roller 56a but also to the clutch flange 10 with the spring clutch 12 locked as described above, thereby rotating the clutch flange 10 in the direction of arrow b. Force acts.

Therefore, when the motor 70 is driven in reverse in order to reversely feed the sheet material 55 as described above, the clutch flange 10 is rotated by the angle α in the direction of arrow b due to the driving force. When the roll diameter is small and the arm 2 is in the position shown in FIG. 6, the positional relationship between the cut portion 4b of the shaft 4 and the hole 10c of the clutch flange 10 is as shown in FIG. 4(b).
Therefore, at the same time as the clutch flange 10 rotates, the shaft 4 is also rotated, and the arm 2 is separated from the sheet material 55 and rotated by an angle α, returning to the initial position shown by the two-dot chain line in FIG. return.

On the other hand, when the roll diameter is large and the arm 2 is in the position shown in FIG.
As shown in (a), after the clutch flange 10 idles by an angle (θ1-θ2), the corner 4c of the cut portion 4b of the shaft 4 is inserted into the straight portion 10d of the hole 10c of the clutch flange 10. contact, the shaft 4 rotates together with the clutch flange 10, and the arm 2 returns to the initial position shown by the two-dot chain line in the figure.

In other words, the position where the arm 2 returns is determined by the straight part 10d of the clutch flange 10 and the corner part 4c of the cut part 4d of the shaft 4, and even if the roll diameter is small,
Even if it is large, the arm 2 will return to the same initial position shown by the two-dot chain line in FIGS. 5 and 6. Therefore, the storage space for the arm 2 only needs to cover the positions shown in FIGS. 5 and 6, and the extra space shown in FIG. 9 is not required, so that the device can be made more compact.

The present invention can be applied to modifications or variations of the above embodiments without departing from the spirit thereof. For example, in one embodiment, the shape of the hole 10c of the clutch flange 10 is D-shaped, but even if it is shaped as shown in FIG. can get. In addition, compared to the first embodiment, the cut portion 4b of the shaft 4 and the contact portion 10d of the clutch flange 10 come into contact with each other on a flat surface. It is preferable from the point of view.

[0057]

As explained above, according to the decurling mechanism of the present invention, the moving means, which is stopped, can be moved to its stopped position in a state where the tension applied to the sheet material and the urging force of the urging means are balanced. Regardless, the control means can control the sheet material to return to a fixed position in a direction in which it is not bent, and the storage space of the moving means can be reduced in size.

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

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. This makes it possible to avoid unnecessarily decurling the sheet material while it is waiting for transportation.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the configuration of a decurling mechanism according to an embodiment.

FIG. 2 is an explanatory diagram of the configuration of a decurling mechanism according to one embodiment.

FIG. 3 is a diagram showing an example in which a decurling mechanism is applied to a facsimile machine.

FIG. 4 is a diagram showing the relationship between the shaft and the clutch flange.

FIG. 5 is an explanatory diagram of a state in which a large-diameter sheet roll is loaded and recording is performed.

FIG. 6 is an explanatory diagram of a state in which a small-diameter sheet roll is loaded and recording is performed.

FIG. 7 is a diagram showing a modification of the cut portion of the shaft.

FIG. 8 is a diagram showing an example in which a conventional decurling mechanism is applied to a facsimile machine.

FIG. 9 is an explanatory diagram of a conventional decurling mechanism in which a large-diameter sheet roll is loaded and recording is performed.

FIG. 10 is an explanatory diagram of a conventional decurling mechanism in which a small-diameter sheet roll is loaded and recording is performed.

FIG. 11 is an explanatory diagram of the configuration of a conventional decurling mechanism.

FIG. 12 is an explanatory diagram of the configuration of a conventional decurling mechanism.

[Explanation of symbols]

2 Arm 4 Axis 8 Clutch gear 10 Clutch flange 12 Spring clutch 18 Guide shaft 51 Main body 52 Lid body 72 Decal shaft

Claims (4)

[Claims] 1. 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, and the guide member. a moving means for moving at least one of the decal members; a biasing means for urging the moving means in a direction in which the bending of the sheet material increases; and a biasing means for pushing the moving means in a direction in which the sheet material does not bend. A decal mechanism comprising: a control means for controlling the amount of movement to be performed; 2. The decurling mechanism according to claim 1, wherein the device main body and the lid are configured to be openable and closable, the decurling member is provided on the lid, and a guide member is provided on the device main body. 3. 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. 4. The decurling mechanism according to claim 1, wherein the moving force of said moving means is set to be larger than the urging force of said urging means of said moving means.