JP2001261205A - Printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printer capable of appropriately aligning recording sheet. SOLUTION: A carriage path to be fed with a color thermal recording sheet 2 is provided with an aligning device comprising a camshaft 28 driven by a motor, rocking levers 29 and 30 locked by rotation of the camshaft 28, slide levers 31 and 32 slid by rocking of the rocking levers 29 and 30, guide members 17 and 18 pressed to align the edges of color thermal recording sheet 2 in a cross direction by sliding of the slide levers 31 and 32, and a plate for pressing and parallelizing the guide members 17 and 18 against the carriage path at the reference position for edges of the color thermal recording sheet 2. In this aligning device, a pair of holding rollers 22 is incorporated for keeping the aligned state with the aligned color thermal recording sheet 2 held between them.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer,
More specifically, the present invention relates to a printer having a positioning unit for positioning a recording sheet.

[0002]

2. Description of the Related Art As in the invention described in Japanese Patent Application Laid-Open No. Hei 10-29356, long recording paper is wound around the outer periphery of a cylindrical winding core in a recording paper used in a printer. There is a roll of recording paper. The recording paper roll is attached to a paper holder and set in a paper supply unit of a printer, a paper supply magazine, or the like. The recording paper of this recording paper roll is rewound on the recording paper roll after use in order to keep the humidity constant.

[0003] The recording paper pulled out from the recording paper roll,
If a skew that advances obliquely to the transport path or a center position deviation of the recording paper from the center position of the transport path occurs, the side edges of the recording paper may be bent or jammed during rewinding. May be. Therefore, various positioning devices for correcting the skew and the center position deviation have been invented.

The alignment apparatus described in Japanese Patent Application Laid-Open No. 8-143183 corrects skew by pressing the leading end of a recording sheet against a pair of conveying rollers, and at the same time, guides both side edges of the recording sheet with guide members. Press to correct the center position.

The positioning apparatus described in Japanese Patent Publication No. 13248/1987 has a fixed guide member disposed on one side edge of the recording paper in the width direction orthogonal to the recording paper conveyance direction. The skew is adjusted by pressing the other side edge of the recording paper with a rotatable movable guide member and pressing it against a fixed guide member.

In the invention described in Japanese Patent Application Laid-Open No. Hei 8-157120, paper holders are attached to both ends of a recording paper roll, and a certain tension is applied to the paper holders to reduce skew and center position deviation during continuous printing. Correction is performed so that stable conveyance can be performed. The correction of the deviation of the center position and the skew immediately after the recording paper is set are performed by performing a plurality of pre-cut processes for cutting the leading edge of the recording paper.

[0007]

In any of the above types of positioning devices, the recording paper pressed by the guide member may be bent so that positioning cannot be performed. This problem occurs in a printer that uses a plurality of types of recording paper having different rigidities or a printer that uses a recording paper roll that requires a strong pressing force during alignment. Further, the recording paper may be skewed again after the alignment is completed due to the twist of the recording paper generated between the recording paper roll and the alignment device.

Further, in the recording paper roll, the recording paper is cut after the printing is completed. If the leading end of the recording paper is not cut at a right angle to the side edge, the recording paper is disclosed in Japanese Unexamined Patent Publication No.
With the positioning device described in JP-A-143283, positioning could not be properly performed.

In the positioning apparatus described in Japanese Patent Publication No. 62-13248, since the movable guide member presses the skewed recording paper in a skewed state, the side edge of the recording paper is fixed to the fixed guide member. Point contact with the edge. As a result, the side edges of the recording paper may buckle or bend.

Further, in a printer using a recording paper roll, when a large number of prints are continuously made on a long recording paper,
The positioning device was retracted from the recording paper. This is to prevent damage to the side edges of the recording paper, particularly to the seal glued portion of the seal type recording paper, and as a result, skew and center displacement may occur during continuous printing. there were.

Further, as in the invention described in Japanese Patent Application Laid-Open No. 8-157120, if the precut processing is performed a plurality of times, there is a problem that the printing time becomes longer and the consumption of recording paper increases.

An object of the present invention is to solve the above-mentioned various problems, and an object of the present invention is to provide a printer which can properly align recording paper.

[0013]

In order to solve the above-mentioned problems, a printer according to the present invention is arranged in a conveying path along which a recording sheet is conveyed so as to face both side edges in the width direction of the recording sheet. A pair of guide members rotatable in a direction facing the recording surface of the recording paper, and moving these guide members toward both side edges of the recording paper, and pressing the two side edges to align them. A positioning drive mechanism for positioning, and a pair of abutting portions that abut against the respective guide members at reference positions of both side edges of the recording paper and regulate the respective guide members so as to be parallel to the recording paper conveyance direction. A positioning means comprising a member is provided.

Further, the abutting member can adjust the position and the angle in the width direction of the recording paper, and the length between the pair of abutting portions is determined by the dimensional tolerance of the length in the width direction of the recording paper. It is the same as the minimum dimension.

In the positioning means, a pair of holding rollers for separating from the recording paper at the time of positioning and for sandwiching the recording paper after the positioning is provided,
The back tension is applied to the recording paper by changing the recording paper conveyance speed of the pair of holding rollers between the paper feeding direction and the returning direction.

[0016] Further, a curved conveyance section in which the recording paper is curved is formed in the conveyance path, and the positioning means is provided in the curved conveyance section so as to position a rigid portion of the recording paper. is there.

In the case where a recording paper roll in which a long recording paper is wound into a roll is used as the recording paper, a flange having a diameter larger than the outer diameter of the recording paper roll is provided on both end surfaces of the recording paper roll. Attach a paper holder with. Thereby, it is possible to correct a skew and a deviation in the center position when the recording paper is pulled out from the recording paper roll or when the recording paper is rewound.

Further, a back tension applying means for applying a back tension to the recording paper between the recording paper roll and the pair of conveying rollers is provided so that the recording paper can be stably conveyed. The back tension applying means includes a feeding back tension mechanism that applies a back tension when the recording paper is conveyed in the paper feeding direction, and a rewinding back that applies the back tension when the recording paper is rewound onto the recording paper roll. And a tension mechanism.

The feed back tension mechanism uses a torque limiter or the like that applies a load to the rotation of the recording paper roll.
The rewinding back tension mechanism uses a rotation drive mechanism that rotates the recording paper roll in the rewinding direction so that the recording paper transport speed is faster than the transport speed of the transport roller pair.

[0020]

FIG. 1 schematically shows a color thermal printer embodying the present invention. In this color thermal printer, a long color thermal recording paper 2 is used as a recording medium. The color thermosensitive recording paper 2 is wound into a roll and handled as a recording paper roll 3, and is sold in a box or the like having a light shielding function. When the recording paper roll 3 is set in the color thermal printer, first, the recording paper roll 3 is accommodated in a paper supply magazine 4 having a light shielding function, and the paper supply magazine 4 is
Set it in the roll chamber of the color thermal printer.

In the paper feed magazine 4, a paper feed roller 6 which comes into contact with the outer peripheral surface of the recording paper roll 3 is rotatably incorporated. Although not shown in detail, a coupling gear is incorporated at a position exposed on the same axis as the paper feed roller 6 outside the paper feed magazine 4. This connecting gear is provided in the feed magazine 4
Is set in the roll chamber and meshes with the drive gear incorporated in the roll chamber. The driving gear is a transfer motor 7
The recording paper roll 3 is rotated in a counterclockwise direction in the drawing to rotate the recording paper 2 to feed the color thermosensitive recording paper 2 from the paper supply magazine 4, and the recording paper roll 3 is rotated in a clockwise direction to rotate the recording paper. 2 is rotated in a rewind direction for rewinding the sheet 2 into the paper feed magazine 4.

The color thermosensitive recording paper 2 is provided with a cyan thermosensitive coloring layer, a magenta thermosensitive coloring layer, a yellow thermosensitive coloring layer, and a protective layer in this order on a support. The yellow thermosensitive coloring layer, which is the uppermost layer in the thermosensitive coloring layer, has the highest thermal sensitivity and develops yellow with small heat energy. The cyan thermosensitive coloring layer, which is the lowermost layer, has the lowest thermal sensitivity and develops cyan with large thermal energy. In addition, the yellow thermosensitive coloring layer
When irradiated with near-ultraviolet light of 420 nm, the coloring ability disappears. The magenta thermosensitive coloring layer develops magenta color with a thermal energy approximately between the yellow thermosensitive coloring layer and the cyan thermosensitive coloring layer, and loses its coloring ability when irradiated with 365 nm ultraviolet rays. For example, a black thermosensitive coloring layer may be provided on the color thermosensitive recording paper 2 to form a four-layer structure.

The color thermosensitive recording paper 2 sent from the paper feed magazine 4 is sent to a transport path provided in the color thermal printer. The color thermosensitive recording paper 2 sent to the conveyance path is sent to an upward vertical conveyance section by being hung on a first guide roller 9. The vertical transport unit is provided with a switching plate 10 for changing the width of the vertical transport unit. The switching plate 10 is incorporated in the vertical transport unit so as to be swingable about the bearing unit 11, and is provided with a shift mechanism 1 including a solenoid or a cam.
2 moves between a regulation position indicated by a solid line in the figure and a widening position indicated by a two-dot chain line in the figure.

The switching plate 10 moves to the regulating position when the color thermosensitive recording paper 2 is transported in the paper feeding direction, and reduces the bending of the color thermosensitive recording paper 2 to prevent the occurrence of a jam. When the color thermosensitive recording paper 2 is aligned and printed, the switching plate 10 moves to the widening position, and the color thermosensitive recording paper 2
To absorb the torsion of the color thermosensitive recording paper 2 generated between the alignment device and the recording paper roll 3 or between the thermal head and the recording paper roll 3, thereby suppressing the skew of the color thermosensitive recording paper 2 and the displacement of the center position. , Breaks, wrinkles, etc. are prevented.

A curved transport section for gently bending the color thermosensitive recording paper 2 is provided downstream of the vertical transport section in the paper feeding direction. The color thermosensitive recording paper 2 is bent by the second guide roller 14 provided in the curving conveyance section. An alignment device 15 as alignment means for performing skew adjustment and centering of the color thermosensitive recording paper 2 is provided in the curved conveyance section.
Is incorporated.

As shown in FIG. 2 and FIG.
Are a pair of guide members 1 arranged so as to sandwich both side ends in the width direction orthogonal to the conveying direction of the color thermosensitive recording paper 2.
7, 18, and a positioning drive mechanism 2 that slides these guide members 17, 18 between a positioning position that sandwiches the color thermosensitive recording paper 2 and a retracted position that is separated from the color thermosensitive recording paper 2.
1 and an abutment plate 19 which is an abutment member for defining the alignment position of the guide members 17 and 18. These components are mounted on a positioning frame 20 in which a thin metal plate is bent so that its cross section has a substantially crank shape.

The guide members 17 and 18 are formed, for example, by bending a thin metal plate so as to have a substantially U-shape. A surface corresponding to the vertical side of the U-shape is a side end of the color thermosensitive recording paper 2. The alignment surfaces 17a and 18a press the edges.
In addition, above the alignment surfaces 17a, 18a, the alignment surfaces 17 are provided.
Bearing portions 17b and 18b are provided so as to be bent in a substantially U-shape in the direction opposite to the directions a and 18a. The bearing portions 17b, 18b are provided with bearing holes 17c, 18c.

The alignment surfaces 17a, 1 of the guide members 17, 18
A circular first opening 17d, 18d and a long hole-shaped second opening 17e, 18e are formed in 8a. A second guide roller 14 for guiding the color thermosensitive recording paper 2 from the vertical transport section to the curved transport section is inserted through the first openings 17d and 18d. Both ends of the second guide roller 14 are rotatably supported by an internal frame of a color thermal printer (not shown). The second opening 17e18e has a pair of holding rollers 22 for nipping and transporting the color thermosensitive recording paper 2 in the curved transport section.
Is inserted. The holding roller pair 22 is also rotatably supported by an internal frame (not shown).

The holding roller pair 22 is movable between a capstan roller 24 driven and rotated by the transport motor 7, a pressing position where the capstan roller 24 is pressed against the capstan roller 24, and a retracted position away from the capstan roller 24. And a pinch roller 25. Pinch roller 25
Is moved between the pressed position and the retracted position by a shift mechanism composed of a solenoid, a cam, and the like. The holding roller pair 22 moves the pinch roller 25 to the retracted position while the color thermosensitive recording paper 2 is being positioned by the positioning device 15 so that the color thermosensitive recording paper 2 can move freely. . Then, after the positioning by the positioning device 15 is completed, the pinch roller 25 is moved to the pressing position to sandwich the color thermosensitive recording paper 2 and maintain the aligned state,
Prevents re-skew and center shift.

The positioning drive mechanism 21 includes a camshaft 28 rotated by a positioning motor 27, and a pair of rocking levers 29 and 30 for converting the rotational motion of the camshaft 28 into a rocking motion.
And a pair of slide levers 31 and 32 for converting the swing movement of these swing levers 29 and 30 into a slide movement. The camshaft 28 includes a pair of shaft support surfaces 35 and 3 provided perpendicular to the upper vertical surface 34 of the positioning frame 20.
6 and a rotating shaft 38 rotatably supported by the rotating shaft 3
8, a pair of cam portions 39 formed symmetrically in the axial direction.
40. These cam portions 39 and 40 are the rotary cams 4 whose thickness is changed along the rotation direction of the cam shaft 28.
1 and 42; cam springs 43 and 44 for urging the rotary cams 41 and 42 toward the center of the cam shaft 28; and receiving plates 45 and 46 for receiving the cam springs 43 and 44. The rotating cams 41 and 42 and the receiving plates 45 and 46 are positioned by pins inserted through the rotating shaft 38.

The swing levers 29 and 30 are formed by forming a thin metal plate into a substantially arrow shape, and are attached to the upper vertical surface 34 of the positioning frame 20 at the end corresponding to the arrow pattern so as to be swingable. Holes 29a and 30a are formed. After the shaft provided on the upper vertical surface 34 is inserted into the holes 29a and 30a, the holes 29a and 30a are stopped by the E-ring.

At the vertices of the parts corresponding to the arrowheads of the swing levers 29 and 30, there are provided upright shafts toward the camshaft 28. A cylindrical roller is rotatably mounted on the outer periphery of these shafts. Attached to link shafts 29b-29d, 30b-3
0d. The upper two of these link shafts
The link shafts 29b, 29c and 30b, 30c sandwich the rotary cams 41, 42 in the axial direction of the cam shaft 28. Thus, while the camshaft 28 makes one rotation, the rotating cams 41, 4
2, the link shafts 29b, 29c and 30b, 30c are pressed, and the swing levers 29, 30 swing from the initial position shown in FIG. 4 to the closed position shown in FIG. 5, and return to the open position again. I do.

The slide levers 31 and 32 are attached to the center inclined surface 48 of the positioning frame 20 so as to be slidable in the left-right direction.
And link surfaces 31b and 32b provided vertically to the slide surfaces 31a and 32a. A pair of long holes 31c, 32c formed along the sliding direction are formed on the slide surfaces 31a, 32a, respectively.
These slots 31c and 32c are provided with the positioning frame 20.
The guide shaft erected on the inclined surface 48 is inserted and is stopped by the E-ring.

The guide members 17, 18 are provided at the ends of the slide surfaces 31a, 32a of the slide levers 31, 32, respectively.
The support shafts 31d and 32d are supported by being inserted into the bearing holes 17c and 18c of the bearing portions 17b and 18b. Thus, the guide members 17 and 18 are rotatable with respect to the inclined surface 48 of the alignment frame 20, that is, the recording surface of the color thermosensitive recording paper 2.

As shown in FIGS. 4 and 5, longitudinally elongated holes 31e and 32e are formed in link surfaces 31b and 32b of slide levers 31 and 32, respectively.
The link shafts 29d and 30d at the lower ends of the swing levers 29 and 30 are inserted into e and 32e. Thus, when the swing levers 29, 30 swing, the slide levers 31, 32 slide in the width direction of the color thermosensitive recording paper 2, and the support shaft 31
The two side edges of the color thermosensitive recording paper 2 are sandwiched between the guide members 17 and 18 attached to d and 32d. As described above, the color thermosensitive recording paper 2 is aligned in the curved conveyance section where the color thermosensitive recording paper 2 is curved, so that the color thermosensitive recording paper 2 has a strong stiffness in the width direction, and buckling, folding, etc. , The color thermosensitive recording paper 2 can be aligned.

As shown in FIG. 6, inside the inclined surface 48 of the alignment frame 20, the alignment surfaces 17a, 18a of the guide members 17, 18 are provided with the contact edges 19a,
A guide plate 50 and a contact plate 19 for controlling the pressing position of the color thermosensitive recording paper 2 by bringing the contact plate 19b into contact therewith are mounted. On the guide plate 50, a plurality of arc-shaped support pieces 50a are provided upright to match the curvature of the color thermal recording paper 2, and the color thermal recording paper 2 applied to the second guide roller 14 is gently curved. The guide is led to the holding roller pair 22.

As shown in FIG. 3, the abutment plate 19 is formed of a thin metal plate, and an opening for avoiding interference between the capstan roller 24 of the holding roller pair 22 and a part of the guide plate 50 is appropriately formed. Is formed. The length between the contact side 19a and the contact side 19b of the attachment plate 19 is the same as the minimum dimension tolerance of the color thermal recording paper 2 in the width direction. Therefore, even if the size of the color thermosensitive recording paper 2 in the width direction varies, the alignment can be performed reliably.

The attachment plate 19 has three screw holes 19c to 19c.
e is formed, and the inclined surface 48 of the alignment frame 20 is formed.
The three screws 52a to 52c are screwed through three holes (not shown) formed on the inner surface of the vehicle to be mounted inside the inclined surface 48. The inclined surface 4 of the positioning frame 20
The hole provided in 8 has a larger diameter than the screws 52a to 52c. Therefore, the position and angle of the abutting plate 19 in the width direction of the color thermosensitive recording paper 2 can be finely adjusted.

On the downstream side of the alignment device 15 in the paper feeding direction, a transport roller pair 54 that sandwiches and transports the color thermosensitive recording paper 2 during printing is arranged. This transport roller pair 54
Are movable between a capstan roller 55 that is driven to rotate by the transport motor 7, a pressure contact position where the capstan roller 55 is pressed against the capstan roller 55 and is driven to rotate, and a retracted position that is separated from the capstan roller 55. And a pinch roller 56. The pinch roller 56 is moved between the pressed position and the retracted position by a shift mechanism including a solenoid and a cam.

On the downstream side in the sheet feeding direction of the pair of conveying rollers 54, the conveying path is directed upward, and a thermal head 58 and a platen roller 59 are arranged so as to sandwich the color thermosensitive recording paper 2. Color thermal recording paper 2 of thermal head 58
A heating element array 5 in which a large number of heating elements are arranged in a line along the width direction of the color thermosensitive recording paper is provided on the surface facing.
8a are provided. The platen roller 59 is located between a pressing position where the platen roller 59 is pressed against the thermal head 58 and the thermal head 5.
8, it is free to move between the evacuation position and
It is moved between the pressed position and the retracted position by a shift mechanism composed of a solenoid, a cam and the like.

The platen roller 59 moves to the pressing position when the color thermal recording paper 2 is transported by the transport roller pair 54 in the rewinding direction, which is the printing direction, and moves to the thermal head 58 via the color thermal recording paper 2. Crimp. The thermal head 58 causes the heating element array 58a to generate heat at a predetermined temperature in accordance with the print data, and causes each thermosensitive coloring layer of the color thermosensitive recording paper 2 to develop a color. The platen roller 59 is driven to rotate in accordance with the conveyance of the color thermosensitive recording paper 2. At the time of paper feeding and paper discharging, the thermal head 5
8 is formed.

On the downstream side of the thermal head 58 in the sheet feeding direction, the transport path is greatly curved, and a yellow fixing device 61 and a magenta fixing device 62 are disposed inside the transport path.
These fixing devices 61, 62 are provided with ultraviolet lamps 63, 64.
And the reflectors 65 and 66, the ultraviolet lamp 63 of the yellow fixing device 61 emits near ultraviolet light having an emission peak of 420 nm, and the ultraviolet lamp 64 of the magenta fixing device 62 emits ultraviolet light having an emission peak of 365 nm. These ultraviolet lamps 63 and 64 fix the yellow and magenta thermosensitive coloring layers of the color thermosensitive recording paper 2 so as not to develop a color even when heated.

Downstream in the feeding direction of the yellow fixing device 61, a paper discharge path 68 for discharging the printed color thermal recording paper 2 and a sub-transport path for temporarily feeding the color thermal recording paper 2 during printing. 69 are provided. The switching between the two transport paths 68 and 69 is performed by a path switching plate 70 that is rotated between a sheet discharge position indicated by a solid line and a printing position indicated by a two-dot chain line.

A paper ejection path 68 includes a cutter 72 for cutting the color thermosensitive recording paper 2 into a sheet-like print,
A discharge roller pair 73 is provided. Paper ejection roller pair 7
3 is driven by a transport motor 7. The color thermosensitive recording paper 2 on which printing is completed is cut by the cutter 72, and is discharged by the discharge tray 74 by the discharge roller pair 73.
Is discharged on top. Thus, the user can obtain the sheet-shaped color print 76.

Although not shown to prevent the drawing from becoming complicated, a guide for the color thermosensitive recording paper 2 is appropriately provided in the transport path in the printer. Recording paper roll 3
The color thermosensitive recording paper 2 sent from the printer moves along the transport path along these guides.

Next, the operation of the above embodiment will be described with reference to FIG.
0 will be described with reference to a flowchart. The color thermal printer receives image data from a recording medium such as a personal computer, a video player, or a memory card on which image data is recorded. The input image data is checked on a monitor connected to the color thermal printer, and when an image to be printed is determined, a print start button provided on the operation panel is operated.

When the print start button is operated,
A system controller that controls each part of the color thermal printer drives the transport motor 7 shown in FIG. 1 to rotate in the forward direction. The forward rotation of the transport motor 7 is transmitted to the paper feed roller 6 via the drive gear of the printer and the connection gear of the paper feed magazine 4. The paper feed roller 6 rotates the recording paper roll 3 counterclockwise in the drawing. As a result, the leading end of the color thermal recording paper 2 is sent out from the transport opening of the paper feed magazine 4 into the transport path in the color thermal printer.

The color thermosensitive recording paper 2 fed into the transport path is sent to an upward vertical transport section by being hung on a first guide roller 9. When the color thermal recording paper 2 is fed, the switching plate 10 of the vertical transport unit is at the regulated position shown by the solid line in the drawing, and the upper second guide roller is provided so as not to generate unnecessary bending of the color thermal recording paper 2. To 14. Thereby, it is possible to prevent the color thermosensitive recording paper 2 from being jammed in the vertical transport unit.

Color thermal recording paper 2 that has passed through the vertical transport section
Is a second guide roller 14 and a guide plate 50 shown in FIG.
And sent into the positioning device 15.
The positioning device 15 immediately after the start of printing is in the initial state shown in FIG. In this initial state, the rotating cam 4 of the cam shaft 28
1, the outer link shafts 29c, 30c are pressed,
The swing levers 29 and 30 are both swung to an open position in which the swing levers are separated from each other. Also, the slide lever 3 engaged with the link shafts 29d, 30d of the swing levers 29, 30
Both 1 and 32 are slid to the open position which is the direction in which they are separated from each other. Thus, the space between the guide members 17 and 18 is widened so that the color thermosensitive recording paper 2 can be easily fed.

In the holding roller pair 22 incorporated in the positioning device 15, the pinch roller 25 is moved to the retracted position during paper feeding. Therefore, the color thermosensitive recording paper 2 passes between the holding roller pair 22 and is sent between the capstan roller 55 and the pinch roller 56 of the transport roller pair 54.

As shown in FIG. 7, when the leading end of the color thermal recording paper 2 reaches between the pair of transport rollers 54, the rotation of the transport motor 7 stops, and the transport of the thermal color recording paper 2 stops. The color thermosensitive recording paper 2 supplied from the paper feed magazine 4 is conveyed in a state where the center line a in the longitudinal direction is skewed or deviated from the center line b of the conveyance path of the color thermosensitive printer. May come.

When the transportation of the color thermosensitive recording paper 2 is stopped,
The color thermal printer drives the shift mechanism 12 to move the switching plate 10 from the regulation position to the widening position.
After the movement of the switching plate 10, the positioning motor 27 of the positioning device 15 is rotationally driven. The positioning motor 27
The camshaft 28 is rotated once. Thereby, the rotating cams 41 and 42 of the cam shaft 28 press the link shafts 29b and 30b inside the swing levers 29 and 30, and from the open state as shown in FIG. 4 to the closed state as shown in FIG. And swing lever 2
Swing 9, 30.

When the swing levers 29 and 30 swing to the closed position, the slide levers 31 and 32 also slide in the direction approaching each other. As shown in FIG. 8, guide members 17 and 18 attached to slide levers 31 and 32 have alignment surfaces 17a and 18 on the side edges of color thermal recording paper 2, respectively.
a is contacted and pressed.

Since the guide members 17 and 18 are rotatably attached to the slide levers 31 and 32, even if the color thermosensitive recording paper 2 is skewed, the guide members 17 and 18 are located at the side edges. It can be contacted in parallel and pressed with a uniform force, and the side edge does not deteriorate due to point contact. The guide members 17 and 1 of the color thermosensitive recording paper 2 are also provided.
8 is gently curved, so that the rigidity in the width direction is higher than that of the flat color thermal recording paper 2. Accordingly, the side edge does not buckle or bend, and proper positioning can be performed.

As shown in FIG. 9, the guide members 17, 18
Is further moved in the direction of pressing the color thermosensitive recording paper 2, the alignment surfaces 17a, 18a of the guide members 17, 18 abut against the abutting sides 19a, 19b of the abutting plate 19, and further sliding is restricted. You. The contact side 19a, 1 of the attachment plate 19
9b is set in parallel with the center line b of the transport path of the color thermal printer, so that the contact sides 19a, 19b
Alignment surfaces 17a, 18 of guide members 17, 18 in contact with
The color thermal recording paper 2 pressed in parallel with the center line b is also corrected in skew and becomes parallel to the transport path. Further, the length between the contact sides 19a and 19b of the contact plate 19 is the same as the minimum size of the dimensional tolerance of the length in the width direction of the color thermosensitive recording paper 2; The centering is reliably performed even if there is a variation in the dimension in the width direction, and the center line a of the color thermosensitive recording paper 2 and the center line b of the transport path overlap.

During the alignment, the color thermosensitive recording paper 2 is twisted between the recording paper roll 3 for regulating the width direction of the color thermosensitive recording paper 2 and the alignment device 15, and the color thermosensitive recording paper 2 is creased. Palm wrinkles may occur. However, in the color thermal printer of the present embodiment, a part of the transport path is widened by moving the switching plate 10 to form a space for absorbing the twist, so that the above problem does not occur.

The rotation of the positioning motor 27 is stopped when the cam shaft 28 is rotated by half a turn. Thus, the positioning device 15 stops in a state where the color thermosensitive recording paper 2 is positioned by the guide members 17 and 18. The system controller operates the shift mechanism for the transport roller pair 54 to move the pinch roller 56 to the pressure contact position, and sandwiches the color thermosensitive recording paper 2. Immediately after this, the system controller operates the shift mechanism for the holding roller pair 22 to move the pinch roller 25 to the pressure contact position, and sandwiches the color thermosensitive recording paper 2.

The system controller comprises a pair of holding rollers 2
After the color thermosensitive recording paper 2 is pinched by the recording paper 2, the positioning motor 27 is rotated half a turn and stopped. In this half rotation, the outer link shafts 29c, 30c are rotated by the rotating cams 41, 42.
Is pressed, the swing levers 29 and 30 move to the open position, and in conjunction with this, the slide levers 31 and 32 also move to the open position. Thereby, the guide members 17, 18
Is released, but the color thermal recording paper 2 is sandwiched between the holding roller pair 22 and the transport roller pair 54 in the aligned state. And the center position does not shift. The holding of the color thermosensitive recording paper 2 by the holding roller pair 22 and the transport roller pair 54 may be performed simultaneously.

Simultaneously with the return of the positioning device 15 to the initial position, the system controller operates the shift mechanism 12 to move the switching plate 10 from the widening position to the regulating position.

The system controller includes a transport motor 7
Is rotated in the forward direction, and the color thermal recording paper 2 is transported in the paper feeding direction by the transport roller pair 54 and the holding roller pair 22. The transport speed of the color thermosensitive recording paper 2 between the transport roller pair 54 and the holding roller pair 22 is set so that the transport roller pair 54> the holding roller pair 22. The tension is applied between. As a result, the amount of wrapping of the color thermal recording paper 2 around the transport roller pair 54 increases, the rotation of the transport roller pair 54 is efficiently transmitted to the color thermal recording paper 2, the transport straight-running stability is improved, and the occurrence of skew is reduced. Can be prevented.

The leading end of the color thermal recording paper 2 transported in the paper feeding direction by the transport roller pair 54 is
8 and the platen roller 59, and passes before the yellow fixing device 61 and the magenta fixing device 62.
At the time of this paper feeding, the color thermosensitive recording paper 2 is sent to the sub-transport path because the path switching plate 70 is at the printing position indicated by the two-dot chain line in the figure.

The transport motor 7 rotates when the length of the color thermal recording paper 2 transported downstream of the heating element array 58a of the thermal head 58 becomes the length of one recording area. Stop. Then, the platen roller 59 is pressed against the thermal head 58 by the operation of the platen shift mechanism, and the color thermosensitive recording paper 2 is sandwiched. Also,
At the same time, the switching plate 10 moves from the regulation position to the widening position.

Next, the system controller rotates the transport motor 7 in the reverse direction, and rotates the transport roller pair 54, the holding roller pair 22, and the paper feed roller 6 in the printing direction which is the rewind direction. As a result, the color thermosensitive recording paper 2 is transported in a direction to be rewound into the paper feed magazine 4. In the conveyance in the printing direction, the conveyance roller pair 54 and the holding roller pair 2
The transport speed of the color thermosensitive recording paper 2 between the paper feed roller 2 and the paper feed roller 6 is as follows. Therefore, tension is applied between the holding roller pair 22 and the transport roller pair 54, and slack occurs between the sheet feeding roller 6 and the holding roller pair 22. This slack occurs in the vertical transport section widened by the switching plate 10, and the twist generated in the color thermosensitive recording paper 2 is absorbed. This prevents the color thermosensitive recording paper 2 from being bent or wrinkled, skewed, or shifted from the center position.

When the leading end of the recording area of the color thermosensitive recording paper 2 reaches the thermal head 58, the heating element array 58
a is heated, and the recording area is heated to thermally record a yellow image line by line on the yellow thermosensitive coloring layer. When the thermal recording of the yellow image ends up to the rear end of the recording area of the color thermal recording paper 2, the transport motor 7 stops. The platen roller 58 moves the thermal head 3 by a shift mechanism.
Move to the evacuation position away from 1. Next, the transport motor 7 rotates in the forward direction again, and transports the color thermosensitive recording paper 2 in the transport direction by the transport roller pair 54 rotating in the transport direction.

At the same time as the conveyance in the feeding direction, the switching plate 10 moves to the regulating position, and the yellow fixing device 6
One ultraviolet lamp 63 is turned on. As a result, the yellow thermosensitive coloring layer in the recording area of the color thermosensitive recording paper 2 is fixed.

When the fixing of the yellow thermosensitive coloring layer in the recording area of the color thermosensitive recording paper 2 is completed, the rotation of the transport motor 7 is stopped, and the driving of the shift mechanism that has lowered the platen roller 59 is stopped. Platen roller 59
Moves to the pressure contact position again to sandwich the thermal recording paper 2 with the thermal head 58, and the switching plate 10 moves to the widening position to absorb the twist of the thermal recording paper 2. The system controller rotates the transport roller pair 54, the holding roller pair 22, and the paper feed roller 6 in the reverse direction by the reverse rotation of the transport motor 7, and transports the color thermosensitive recording paper 2 in the printing direction. When the leading end of the recording area of the color thermal recording paper 2 reaches the thermal head 58, the heating element array 58a starts generating heat and thermally records a magenta image line by line on the magenta thermosensitive coloring layer.

When the thermal recording of the magenta image is completed up to the rear end of the recording area of the color thermal recording paper 2, the transport motor 7
Stops, and the platen roller 59 moves to the retracted position.
At the same time, the switching plate 10 moves to the regulation position.
The transport motor 7 rotates again in the forward direction to transport the color thermosensitive recording paper 2 in the paper feeding direction. At the same time as the conveyance in the paper feeding direction, the ultraviolet lamp 6 of the magenta fixing device 62 is used.
4 lights up, and the magenta thermosensitive coloring layer in the recording area of the color thermosensitive recording paper 2 is fixed.

When the fixing of the magenta thermosensitive coloring layer in the recording area of the color thermosensitive recording paper 2 is completed, the rotation of the transport motor 7 is stopped, the platen roller 59 moves to the pressing position, and the switching plate 10 moves to the widening position. Moving. Further, the color thermosensitive recording paper 2 is conveyed in the printing direction by the reverse rotation of the conveyance motor 7, and when the leading end of the recording area reaches the thermal head 58, the heating element array 58 a starts to generate heat and the cyan thermosensitive coloring layer is formed. The cyan image is thermally recorded line by line.

When the thermal recording of the cyan image is completed up to the rear end of the recording area of the color thermal recording paper 2, the transport motor 7 is stopped, the platen roller 59 is moved to the retracted position, and the switching plate 1 is moved to the retracted position.
0 moves to the regulation position, and the path switching plate 70 moves to the paper discharge position. Next, the transport motor 7 rotates again in the forward direction and transports the color thermosensitive recording paper 2 in the paper feeding direction. Since the cyan thermosensitive coloring layer has a coloring property that does not form a color in a normal storage state, no fixing process is performed.

Color thermal recording paper 2 conveyed in the paper feeding direction
The sheet is sent to the sheet discharge path 68 by contacting the path switching plate 70, and is sent out onto the sheet discharge tray 74 by the sheet discharge roller pair 73. When the rear end of the recording area of the color thermosensitive recording paper 2 reaches the position of the cutter 72, the rotation of the transport motor 7 is temporarily stopped, and the cutter 72 operates.

As a result, the color thermosensitive recording paper 2 is cut into a sheet-shaped color print 76, which is stacked on the paper discharge tray 74. Finished color print 76
Before printing, alignment including skew adjustment and centering of the color thermosensitive recording paper 2 is performed, and the conveying roller pair 54
Since the printing is performed while the alignment state is maintained by the holding roller pair 22 and the alignment state, the image is of high quality without tilt of the image or displacement of the center position.

After the printing is completed, the system controller rotates the transport motor 7 in the reverse direction, and rewinds the color thermosensitive recording paper 2 into the paper feed magazine 4 to prevent moisture.

In the above-described embodiment, the processes from sheet feeding to printing are performed according to the flowchart of FIG. 10. However, when the distance from the alignment device to the pair of conveying rollers is long, the alignment of the color thermosensitive recording paper is not performed. Difficult to do. Therefore, when the distance between the alignment device and the conveying roller pair is long, it is preferable to perform the processes from sheet feeding to printing in the following procedure. 1. 1. The color thermal recording paper is transported to just before the nip position of the transport roller pair. Alignment 3. 3. Holding roller pair pressure contact Unalignment 5. 5. Convey color thermal recording paper to nip position of conveying roller pair 6. Conveyor roller pressure contact According to this, after the color thermosensitive recording paper is properly aligned, the color thermosensitive recording paper can be conveyed to the pair of conveying rollers while maintaining the color thermosensitive recording paper in the aligned state.

The pair of guide members presses the side edge of the color thermosensitive recording paper 2 with the same pressing force. However, one pressing force is made stronger than the other and the one pressing member presses the side edges. The color thermosensitive recording paper may be positioned in contact with the other guide member. In order to change the pressing force of the guide member, for example, the slide amounts of the guide members 17 and 18 are changed by changing the shapes of the slide levers 31 and 32, the swing levers 29 and 30, and the rotating cams 41 and 42 on the left and right. The difference between the biasing forces of the cam springs 43 and 44 may be provided.

Further, the abutment plate for regulating the guide member is formed from a single plate. However, two abutment plates may be formed corresponding to each guide member so that their positions and angles can be adjusted.

In each of the above embodiments, a color thermal printer using a roll of color thermal recording paper has been described as an example. However, the present invention can also be applied to a color thermal printer using sheet color thermal recording paper. it can.

Further, in the above-described embodiment, the color thermal printer having the transport path in which the color thermal recording paper is bent at several places has been described as an example. However, the present invention is also applied to the color thermal printer having the linear transport path. Positioning means can be used. Hereinafter, an embodiment will be described in which the alignment means of the present invention is incorporated in a color thermal printer having a linear transport path.

FIG. 11 is a schematic diagram showing the configuration of a color thermal printer using another embodiment of the present invention. This color thermal printer uses a recording paper roll 81 in which a long color thermal recording paper 80 is wound in a roll shape.

In the roll chamber in which the recording paper roll 81 is set, there is provided a paper feed roller 83 in contact with the outer peripheral surface of the recording paper roll 81. The paper feed roller 83 is moved by a shift mechanism (not shown) between a paper feed position where it comes into contact with the outer peripheral surface of the recording paper roll 81 to prevent loosening, and a retracted position away from the outer peripheral surface of the recording paper roll 81. It is free. The paper feed roller 83 is driven by the transport motor 84 when it is at the paper feed position, rotates clockwise, rotates the recording paper roll 91 counterclockwise, and sends out the color thermosensitive recording paper 80.

On the downstream side of the color thermosensitive recording paper 80 in the feeding direction, there is provided a positioning device 85 which presses both side edges of the color thermosensitive recording paper 80 to correct the skew and the center position deviation. The positioning device 85 includes a pair of guide members that face both side edges of the color thermosensitive recording paper 80 and a positioning drive mechanism that moves the guide members in a direction of pressing both side edges of the color thermosensitive recording paper. Have. Except for the point corresponding to the color thermosensitive recording paper 80 conveyed linearly and the point that the holding roller for sandwiching the color thermosensitive recording paper 80 after alignment is not provided, it is used in the above-described embodiment. Since the positioning device is the same as the positioning device 15, the detailed description is omitted.

At the downstream side of the positioning device 85, a transport roller pair 89 including a capstan roller 87 and a nip roller 88 is disposed. The capstan roller 87 is rotated by a transport motor 84. Nip roller 88
Is a pressing position at which the capstan roller 87 is pressed against the capstan roller 87 by a shift mechanism (not shown).
Move to the evacuation position away from The color thermosensitive recording paper 80 is fed by the conveying roller pair 89 to the paper feeding direction where the recording paper roll 81 is pulled out from the recording paper roll 81.
Is transported in the rewind direction where it is wound up.

A thermal head 91 and a platen roller 92 facing the thermal head 91 are disposed downstream of the transport roller pair 89. Thermal head 9
A heating element array 91a is provided on a surface facing one color thermosensitive recording paper 80. Platen roller 92
Is a thermal head 91 by a shift mechanism (not shown).
Is movable between a pressure contact position where it is pressed against the thermal head 91 and a retracted position where it is separated from the thermal head 91.

Downstream of the thermal head 91, a yellow fixing device 94 for fixing the yellow thermosensitive coloring layer of the color thermosensitive recording paper 80 and a magenta fixing device 95 for fixing the magenta thermosensitive coloring layer are arranged. .

On the downstream side of the yellow fixing device 94, a paper discharge roller pair 97 and a cutter 98 that cuts the color thermosensitive recording paper 80 to form a sheet print are arranged. The discharge roller pair 97 includes a capstan roller 99 driven by a transport motor 84, and a nip roller 100 which is movable between a pressing position where the capstan roller 99 is pressed against the capstan roller 99 and a retracted position where the capstan roller 99 is separated. .
The discharge roller pair 97 has a transport speed slightly lower than that of the transport roller pair 89.
7 transports the color thermosensitive recording paper 80 by a predetermined length.

The color thermosensitive recording paper 80 on which printing has been completed
Is cut by the cutter 98 and the discharge roller pair 9
7, the paper is discharged from the paper discharge port 101. This allows
The user can obtain a sheet-shaped color print.

A first sensor 103 and a second sensor 104 for detecting the leading edge of the color thermosensitive recording paper 80 are disposed on the downstream side of the transport roller pair 89 and on the downstream side of the paper discharge roller pair 97. . As the first sensor 103 and the second sensor 104, for example, a reflective photoelectric sensor is used.
When the first sensor 103 and the second sensor 104 detect the leading end of the color thermal recording paper 80, the detection signal is input to a system controller that controls the entire color thermal printer.

As shown in FIG. 12, paper holders 105 and 106 having flanges 105a and 106a having a diameter larger than the outer diameter of the recording paper roll 81 are attached to both ends of the recording paper roll 81. Paper holder 1
05 and 106 have cylindrical fitting portions 105b and 106, respectively.
b, the fitting portions 105b and 106b are fitted into the core 108 of the recording paper roll 81,
The paper holders 105 and 106 are fitted on the recording paper roll 81.

The flanges 105a and 106a of the paper holders 105 and 106 hold the both side edges of the color thermosensitive recording paper 80 and both end surfaces of the recording paper roll 81 when the color thermosensitive recording paper 80 is rewound onto the recording paper roll 81. Hold down. This prevents the color thermosensitive recording paper 80 from being wound around the recording paper roll 81 with the center position shifted.

A gear 110 is provided on the outer end face of one of the paper holders 105. A back tension applying device 111 connected via the gear 110 applies a back tension to the color thermosensitive recording paper 80.

The back tension applying device 111 includes a gear 112 meshing with the gear 110, a torque limiter 113 provided coaxially with the gear 112, a gear 114 provided coaxially with the torque limiter 113, and a gear 114 A gear 117 meshes with the gear 117, a gear 116 meshes with the gear 117, and a rewind motor 115 for rotating the gear 116.

In the back tension applying device 111, when the color thermosensitive recording paper 80 is pulled out from the recording paper roll 81 and the paper holders 105 and 106 rotate counterclockwise, the gear 11 is rotated by the torque limiter 113.
A load is applied to the second rotation. As a result, a load is applied to the rotation of the recording paper roll 81, and a back tension is applied to the conveyance of the color thermosensitive recording paper 80.

When rewinding the color thermosensitive recording paper 80 to the recording paper roll 81, the rewinding motor 115 operates. The torque limiter 113 transmits the rotation of the gears 116 and 117 to the gear 112, and
Rotate 06 clockwise. When the color thermosensitive recording paper 80 is rewound, the take-up speed of the recording paper roll 91 is set to be faster than the conveyance speed of the conveyance roller pair 89, so that the recording paper roll 81 and the conveyance roller pair 89 are used.
A back tension is applied to the color thermosensitive recording paper 80 between.

Next, the operation of the above embodiment will be described with reference to the flowcharts of FIGS. The color thermal printer receives image data from a recording medium such as a personal computer, a video player, or a memory card on which image data is recorded. The input image data is checked on a monitor connected to the color thermal printer, and when an image to be printed is determined, a print start button provided on the operation panel is operated.

When the print start button is operated,
The system controller that controls the components of the color thermal printer drives the transport motor 84 shown in FIG. 11 to rotate in the forward direction. The forward rotation of the transport motor 84 is transmitted to the paper feed roller 83. The paper feed roller 83 rotates the recording paper roll 81 counterclockwise in the drawing. As a result, the leading end of the color thermal recording paper 80 is sent out into the transport path in the color thermal printer.

The color thermosensitive recording paper 80 is sent to a positioning device 85 and a conveying roller pair 89. The positioning device 85 at the start of printing is at an initial position where the guide members that press the both side edges of the color thermal recording paper 80 are separated from the color thermal recording paper 80. Further, since the nip roller 88 is at the retracted position where the nip roller 88 is separated from the capstan roller 87, the conveyance roller pair 89 does not hinder the conveyance of the color thermosensitive recording paper 80.

The first sensor 103 detects the leading edge of the color thermosensitive recording paper 80 that has passed through the pair of conveying rollers 89. The detection signal of the first sensor 103 is input to the system controller. Upon receiving this detection signal, the system controller stops the transport motor 84,
The feeding of the color thermosensitive recording paper 80 is stopped. Further, the paper feed roller 83 is moved to a retracted position away from the recording paper roll 81 by a shift mechanism (not shown).

Next, the positioning device 85 is operated to press both side edges of the color thermosensitive recording paper 80, so that the skew and the deviation of the center position are corrected. After the alignment of the color thermal recording paper 80 is completed, the nip roller 88 of the transport roller pair 89 is pressed against the capstan roller 87 to sandwich the color thermal recording paper 80, and the skew and the center position deviation are maintained. After the transfer of the color thermal recording paper 80 by the pair of conveying rollers 89, the alignment device 85 moves the guide member to a retracted position away from the color thermal recording paper 80, and ends the alignment.

The system controller includes the transport motor 8
4 is operated, and the color thermosensitive recording paper 8 is
0 in the paper feeding direction. At the time of transport in the paper feeding direction, as shown in FIG. 12, the torque limiter 113 applies a load to the rotation of the recording paper roll 81, so that the color thermal recording paper 80 is transported between the transport roller pair 89 and the recording paper roll 81. Is given back tension. This allows
The conveyance of the color thermosensitive recording paper 80 is stabilized, and the occurrence of skew, center position shift, and the like is prevented.

When the leading end of the recording area of the color thermosensitive recording paper 80 reaches the heating element array 91a of the thermal head 91, the conveyance of the color thermosensitive recording paper 80 by the conveying roller pair 89 is stopped. The transport amount of the color thermosensitive recording paper 80 can be obtained by detecting the rotation amount of the nip roller 88 with an encoder.

After the transportation of the color thermosensitive recording paper 80 is stopped, the platen roller 92 moves to a pressure contact position where the color thermosensitive recording paper 80 is pressed against the thermal head 91, and the thermal recording paper 80 is sandwiched between the platen roller 92 and the thermal head 91. The transport roller pair 89 starts transporting the color thermal recording paper 80 in the rewinding direction, and at the same time, the thermal head 91 causes the heating element array 91a to generate heat so that one line of the yellow image is recorded on the recording area of the color thermal recording paper 80. Heat record each time.

During the transport in the rewind direction during the yellow image thermal recording, the rewind motor 115 operates. The recording paper roll 81 is rotated clockwise in FIG. 11, and winds the color thermosensitive recording paper 80 around the outer periphery. Further, the rotation speed of the recording paper roll 81 at this time is set to a rotation speed at which the color thermal recording paper 80 can be wound up at a speed slightly higher than the transportation speed of the color thermal recording paper 80 by the transport roller pair 89. The recording paper roll 81
A back tension is applied between the pair and the conveying roller pair 89. Accordingly, the conveyance of the color thermosensitive recording paper 80 is stabilized, and the occurrence of skew, center position shift, and the like is prevented.

The color thermosensitive recording paper 80 wound around the recording paper roll 81 is provided with paper holders 105 and 106.
Side edges are pressed by the flanges 105a and 106a. As a result, the color thermosensitive recording paper 80 is aligned with respect to the recording paper roll 81.
The side edge of the recording paper roll 81 is not shifted and wound with respect to the end face of the recording paper roll 81.

When the thermal recording of the yellow image is completed, the conveyance of the color thermosensitive recording paper 80 by the conveyance roller pair 89 is stopped, and the platen roller 92 moves to the retreat position away from the thermal head 91. The system controller conveys the color thermosensitive recording paper 80 again in the paper feeding direction by the conveying roller pair 89, turns on the ultraviolet lamp of the yellow fixing device 94, and fixes the yellow thermosensitive coloring layer in the recording area. When fixing the yellow thermosensitive coloring layer,
Since a back tension is applied to the color thermosensitive recording paper 80 by the torque limiter 113, no skew, center position shift, or the like occurs.

When the fixing of the yellow thermosensitive coloring layer in the recording area is completed, the conveying roller pair 89 is rewound to the position where the head of the recording area of the color thermosensitive recording paper 80 faces the heating element array 91 a of the thermal head 91. And stopped. When the color thermosensitive recording paper 80 is conveyed at this time, the back tension is applied between the recording paper roll 81 and the conveying roller pair 89 by the back tension applying device 111, and the recording paper 80 is aligned by the paper holders 105 and 106. There is no occurrence of skew, center position shift or the like.

After the transport roller pair 89 stops, the platen roller 92 presses against the thermal head 91 to sandwich the color thermosensitive recording paper 80. The conveyance roller pair 89 resumes conveyance of the color thermal recording paper 80 in the rewinding direction, and the thermal head 91 causes the heating element array 91a to generate heat so that the magenta image is recorded one line at a time on the recording area of the color thermal recording paper 80. Record heat. Also during the thermal recording of the magenta image, the recording paper roll 81 is
The back tension is applied between the paper roller pair 89 and the paper feed roller pair 89, and the paper holders 105 and 106 align the paper, so that no skew or center position deviation occurs.

When the thermal recording of the magenta image is completed, the transport roller pair 89 stops transporting the color thermal recording paper 80. After the platen roller 92 moves to the retracted position, the color thermosensitive recording paper 80 is transported in the paper feeding direction, and the magenta thermosensitive coloring layer in the recording area is fixed by the magenta fixing device 95. Even when the magenta thermosensitive coloring layer is fixed, a back tension is applied to the color thermosensitive recording paper 80, so that no skew or center position shift occurs.

When the fixing of the magenta thermosensitive coloring layer is completed,
The conveying roller pair 89 is such that the head of the recording area of the color thermosensitive recording paper 80 has a heating element array 91 a of the thermal head 91.
Is transported in the rewinding direction to a position facing the. At this time, the skew, the center position shift, and the like do not occur even when the color thermosensitive recording paper 80 is transported.

After the conveyance roller pair 89 stops, the platen roller 92 is pressed against the thermal head 91 to sandwich the color thermosensitive recording paper 80. The conveyance roller pair 89 resumes conveyance of the color thermal recording paper 80 in the rewinding direction, and the thermal head 91 thermally records a cyan image line by line on the recording area of the color thermal recording paper 80. Even during the thermal recording of the cyan image, there is no occurrence of skew, center position shift, or the like.

When the thermal recording of the cyan image is completed, the transport roller pair 89 stops the transport of the color thermal recording paper 80 once. Then, after the platen roller 92 moves to the retreat position, the color thermosensitive recording paper 80 is transported again in the paper feeding direction. The leading edge of the color thermal recording paper 80 is the second sensor 10
4, the detection signal is input to the system controller. The system controller once stops the conveyance of the color thermal recording paper 80, and switches the nip roller 100 of the discharge roller pair 97 to the capstan roller 99.
To press the color thermosensitive recording paper 80 therebetween.

The paper discharge roller pair 97 is provided for the color thermosensitive recording paper 8.
0 is conveyed toward the paper exit 101, and the color thermal recording paper 8
When the zero cut position faces the cutter 98, the conveyance is temporarily stopped. Since the transport speed of the color thermal recording paper 80 by the discharge roller pair 97 is slightly lower than the transport speed by the transport roller pair 89, the transport of the color thermal recording paper 80 to the cut position is performed by the discharge roller pair. 97. The back tension applying device 111 is provided between the conveying roller pair 89 and the recording paper roll 81.
As a result, the back tension is continuously applied to the color thermosensitive recording paper 80, so that no skew or center position deviation occurs.

The cutter 98 cuts the color thermosensitive recording paper 80 to form a sheet-shaped color print. The created color print is discharged from the discharge port 101 to the outside of the color thermal printer.

Thereafter, the pinching of the color thermosensitive recording paper 80 by the discharge roller pair 97 is released, and the transport roller pair 89 is released.
The color thermosensitive recording paper 80 is conveyed in the rewind direction. At the time of rewinding, the back-tension is applied to the color thermosensitive recording paper 80, so that skew, center position deviation, and the like do not occur.

When continuous printing is instructed in the first printing operation, the leading edge of the recording area of the color thermosensitive recording paper 80 is heated by the heating element array 91 of the thermal head 91.
The sheet is transported to a position facing a, and the above-described printing operation is repeated again. When the continuous printing is not instructed, the leading edge of the color thermosensitive recording paper 80 is the first edge.
At the time point when the detection is made by the sensor 103, the pinching of the color thermosensitive recording paper 80 by the conveying roller pair 89 is released. Thereafter, when the color thermosensitive recording paper 80 is rewound to the recording paper roll 81 to its leading end, the paper feed roller 83 is pressed against the outer peripheral surface of the recording paper roll 81 to prevent loosening.

In each of the above embodiments, a color thermal printer has been described as an example. However, the present invention can also be applied to a thermal transfer type thermal printer, a printer using a recording method other than the thermal printer, a copying machine, and the like.

[0115]

As described above, in the printer according to the present invention, the pair of guide members are rotatable in the direction facing the recording surface of the recording paper. The edge does not deteriorate due to point contact. In addition, the guide member is brought into contact with the abutment members arranged at the reference positions of both side edges of the recording paper, and the guide member itself is aligned, so that the alignment and centering of the recording paper can be performed only by the guide member. Can be performed simultaneously. In addition, the length between the abutting portions of the abutting members is the same as the minimum dimension tolerance of the width in the width direction of the recording paper. Can be ranked.

Further, since the pair of holding rollers which separates from the recording paper during alignment and sandwiches the recording paper after alignment is provided in the alignment means, the alignment state of the recording paper is maintained even after the alignment is released by the alignment means. can do. Further, since the transport speed of the pair of holding rollers is made different from the transport speed of the pair of transport rollers, back tension is applied to the recording paper, thereby preventing skew and center displacement.

Further, since a curved conveyance section in which the recording paper is curved is formed in the conveyance path and the alignment means is incorporated in the curved conveyance section, the rigidity of the recording paper is improved, and the recording paper at the time of the alignment is improved. Buckling and breakage can be prevented and proper positioning can be performed.

Further, since a paper holder provided with a flange having a diameter larger than the outer diameter of the recording paper roll is attached to both end surfaces of the recording paper roll, the recording paper can be adjusted even when it is rewound to the recording paper roll. Position, and the occurrence of skew and center position deviation at the time of next printing can be reduced.

Further, a back tension applying means for applying a back tension to the recording paper between the recording paper roll and the pair of conveying rollers is provided to stabilize the conveyance. The displacement does not occur again.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating a configuration of a color thermal printer embodying the present invention.

FIG. 2 is an external perspective view of the positioning device.

FIG. 3 is an exploded perspective view showing a configuration of a positioning drive mechanism.

FIG. 4 is a front view of the positioning device in a positioning release state.

FIG. 5 is a front view of the positioning device in a positioning state.

FIG. 6 is a perspective view of the positioning device as viewed from below.

FIG. 7 is a plan view of the positioning device before starting positioning.

FIG. 8 is a plan view of the positioning device at the time of positioning.

FIG. 9 is a plan view of the positioning device when positioning is completed.

FIG. 10 is a flowchart illustrating an operation sequence from sheet feeding to printing.

FIG. 11 is a schematic diagram showing a configuration of a color thermal printer using another embodiment of the present invention.

FIG. 12 is an exploded perspective view showing a configuration of a paper holder and a back tension applying device.

FIG. 13 is a flowchart illustrating a sequence from the start of printing to printing of a yellow image according to another embodiment.

FIG. 14 is a flowchart showing a sequence from the fixing of the yellow thermosensitive coloring layer to the completion of preparation for printing a cyan image.

FIG. 15 is a flowchart illustrating a sequence from printing of a cyan image to rewinding of a recording sheet.

FIG. 16 is a flowchart illustrating an operation after printing is completed.

[Explanation of symbols]

 2,80 color thermal recording paper 3,81 recording paper roll 4 paper supply magazine 6,83 paper supply roller 7,84 transport motor 10 switching plate 12 shift mechanism 15,85 alignment device 17,18 guide member 19 contact plate DESCRIPTION OF SYMBOLS 21 Positioning drive mechanism 22 Holding roller pair 27 Positioning motor 28 Cam shaft 29, 30 Swing lever 31, 32 Slide lever 54, 89 Transport roller pair 58, 91 Thermal head 59, 92 Platen roller 106 Paper holder 111 Back tension Applicator

Claims (11)

[Claims] An image forming apparatus includes: a paper feed unit on which recording paper is set; a pair of transport rollers that sandwich and transport the recording paper supplied from the paper feed unit; and a print head that prints on the recording paper being transported. In a printer, a pair of recording paper is arranged in a transport path from the paper feeding unit to the print head, facing both side edges of the recording paper, and rotatable in a direction facing the recording surface of the recording paper. A guide member, a positioning drive mechanism for moving these guide members toward both side edges of the recording paper, and pressing and aligning both side edges; A printer comprising: a positioning member having a pair of abutting members that abut against the member and regulate each guide member so as to be parallel to the recording paper conveyance direction. 2. The printer according to claim 1, wherein the abutting member is capable of adjusting a position and an angle in a width direction of the recording paper. 3. The printer according to claim 1, wherein a length between the pair of abutting portions is equal to a minimum dimension tolerance of a length in a width direction of the recording paper. 4. The printer according to claim 1, wherein a pair of holding rollers that separates from the recording paper during alignment and sandwiches the recording paper after alignment is provided in the alignment unit. 5. The pair of holding rollers are disposed upstream of the pair of conveying rollers in the sheet feeding direction, and the conveying speed in the sheet feeding direction is slower than that of the pair of conveying rollers. 5. The printer according to claim 4, wherein the transport speed is set faster than the transport roller pair. 6. A printer according to claim 1, wherein a curved transport section for bending the recording paper is formed in the transport path, and the alignment means is provided in the curved transport section. . 7. The recording paper comprises a recording paper roll in which a long recording paper is wound in a roll shape, and a paper holder having a flange having a diameter larger than the outer diameter of the recording paper roll is attached to both end faces. The printer according to claim 1, wherein the printer is set in a paper feeding unit. 8. The printer according to claim 7, further comprising a back tension applying unit that applies a back tension to the recording paper between the recording paper roll and the pair of conveying rollers. 9. A feeding back tension mechanism for applying a back tension when a recording sheet is conveyed in a paper feeding direction, and a back tension for rewinding the recording sheet to a recording sheet roll. 9. The printer according to claim 8, further comprising a back tension mechanism for rewinding. 10. The feeding back tension mechanism,
10. The printer according to claim 9, further comprising a torque limiter for applying a load to the rotation of the recording paper roll. 11. The rewinding back tension mechanism comprises a rotation drive mechanism for rotating a recording paper roll in a rewinding direction so that a recording paper transport speed is faster than a transport speed of a transport roller pair. 10. The printer according to claim 9, wherein: