JP2002316753A - Tip gripping device of recording paper of printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To certainly separate a recording paper from a recording paper roll. SOLUTION: This tip gripping device 21 comprises a support arm 43, a tip gripping clip 44, and a cam 45. The recording paper roll 12 rotates in the unwinding direction after printing. Synchronously with the unwinding, the tip gripping clip 44 rotates via the support arm 43. When the recording paper roll 12 rotates in the unwinding direction and the tip of the recording paper 14 moves to the proximity of a pair of paper feeding rollers 17, the tip gripping clip 44 runs after the tip of the recording paper 14 and nips it. When the tip gripping clip 44 moves to the proximity of a driving roller 15 while nipping the tip of the recording paper 14, the rotation of the support arm 43 stops and simultaneously the driving roller 15 stops. The tip of the recording paper 14 is pressed onto the outer periphery of the recording paper roll 12 while being gripped with the tip gripping clip 44.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording paper leading edge gripping device for use in a printer which uses a recording paper roll such as thermal recording paper or photographic paper, and rewinds the recording paper in a clipped state. is there.

[0002]

2. Description of the Related Art In thermal printers and photographic printers,
A long recording paper is used. The recording paper roll is stored directly in the roll chamber of the printer or via a paper feed magazine,
For example, a forward rotation in the paper feeding direction and a reverse rotation in the rewinding direction are performed by a driving roller abutting on the outer periphery of the recording paper roll as disclosed in JP-A-2000-169004.

A separation plate is provided in the vicinity of the drive roller. When the recording paper roll rotates forward during paper feeding, the leading end of the recording paper is separated from the recording paper roll by the separation plate and supplied to a printing unit. In the printing section, for example,
As described in JP-A-77510 and JP-A-7-149014, a pair of conveying rollers is provided.
An image is recorded on recording paper by color plane sequential. After the end of the printing process, the recording portion is cut into a predetermined size and then discharged out of the printer. The portion of the recording paper not used for image recording is wound around the outer periphery of the recording paper roll by the reverse rotation of the recording paper roll.

[0004] By the way, the recording paper roll is wound in a roll shape with the recording surface inside, but when the recording paper has been rewound, the recording paper must be brought into close contact with the outer periphery of the recording paper roll. Accordingly, it is possible to prevent moisture from entering through a gap between the recording paper and the outer periphery of the recording paper roll. If the recording surface is moist, the coloring characteristics of the recording paper change, and the reproducibility of the recorded image deteriorates.

When the leading edge of the recording paper is wound around the outer periphery of the recording paper roll to prevent moisture, if the recording paper roll is rotated forward during paper feeding, jamming may occur. In other words, when the leading end of the recording paper is at a position below the separation plate, if the leading end of the recording paper roll is rotated forward, the leading end of the recording paper roll is separated from the outer periphery of the recording paper roll and hangs down.
Jamming occurs. This jamming occurs frequently on recording paper having a weak stiffness.

In order to prevent jamming, the recording paper roll is once reversed at the start of paper feeding. During the reverse rotation, the leading edge of the recording paper is detected by the leading edge detecting device, and when the leading edge is slightly above the separation plate, the recording paper roll is stopped.
Next, the recording paper roll is rotated forward to send the recording paper to the printing section.

[0007]

In the above-mentioned conventional printer, there is a problem that a leading edge detecting device is required, and since the reverse rotation for detecting the leading edge is required, a long sheet feeding time is required.

Further, when a recording paper having a small thickness and a low stiffness is used, the leading end of the recording paper may be stuck to the outer periphery of the recording paper roll due to static electricity or the like. There was a problem that was not done.

According to the present invention, there is provided a printer capable of improving the moisture resistance of a recording sheet after the recording sheet has been wound on the recording sheet roll with a simple configuration and reliably separating the recording sheet from the recording sheet roll. An object of the present invention is to provide a recording paper leading end holding device.

It is another object of the present invention to provide a recording paper leading end gripping device for a printer capable of shortening a paper feeding time by omitting reverse rotation of a recording paper roll.

[0011]

In order to achieve the above object, a printer according to the present invention rotates a recording paper roll forward at the time of paper feeding, and feeds out the leading end of the recording paper wound into a roll onto a conveyance path. In a printer in which the recording paper roll is reversed after printing to return the leading edge of the recording paper to the outer periphery of the recording paper recording paper roll, a closed state for holding the leading end of the recording paper, and the leading edge of the recording paper are taken in and out. An end holding clip that is displaced to an open state to allow the recording paper roll to move from a first position close to the recording paper roll to a second position away from the recording paper roll when the recording paper roll rotates forward; A clip moving means for moving the tip holding clip toward the first position from the second position to the first position when the recording paper roll rotates in the reverse direction; 1 When it is in the closed position, the leading edge of the recording paper is held in the closed state, and when moving away from the transport path from the first position to the second position, the leading end holding clip is changed from the closed state to the open state. When the clip is displaced to release the leading end of the recording paper, the leading end clip is opened when the leading end holding clip is at the second position, and when entering the transport path during the movement from the second position to the first position. And a clip opening / closing means for displacing the leading end holding clip from the open state to the closed state to hold the leading end of the recording paper.

It is preferable that the clip for holding the distal end is composed of a pair of clip pieces that can move in opposite directions about a shaft, and a spring that urges these clip pieces to close them. Preferably, the clip moving means includes a support arm having one end attached to a shaft of the clip for holding the distal end, and a motor for rotating the arm around the other end of the support arm. The clip opening / closing means includes a pair of pins provided on each clip piece,
It is preferable to include a cam arranged along the movement trajectory of these pins and pushing each pin in the opposite direction to open the tip holding clip.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A color thermal printer 1 shown in FIG.
0, a roll chamber 11 is provided.
1, the recording paper roll 12 is directly set. The recording paper roll 12 includes a core 13 and a long recording paper 14 wound around the core 13 in a roll shape. Recording paper 14
A known color thermosensitive recording paper in which a cyan thermosensitive coloring layer, a magenta thermosensitive coloring layer, and a yellow thermosensitive coloring layer are sequentially provided on the recording surface side is used, and is wound with the recording surface inside.

The roll chamber 11 is provided with a driving roller 15, a separating plate 16, and a sheet feeding roller pair 17. The drive roller 15 rotates the recording paper roll 12 forward in the paper feeding direction and reversely rotates it in the rewinding direction while abutting on the outer periphery of the recording paper roll 12. The drive roller 15 is coated with a coating material such as rubber around a metal shaft to prevent slippage. The recording paper roll 12 is biased by a spring (not shown) toward the drive roller 15, and the outer periphery thereof always contacts the drive roller 15. Thus, even if the winding diameter changes during use, the recording paper roll 12 rotates properly.

The separation plate 16 elastically contacts the outer peripheral surface of the recording paper roll 12, and the leading end 14a of the recording paper 14 (FIG. 3).
) Is separated from the outer peripheral surface of the recording paper roll 12. The separation plate 16 performs the leading end separation only when the recording paper roll 12 is loaded. That is, when the recording paper roll 12 rotates forward, the recording paper roll 12 is separated by the separation plate 16 such that the leading end 14 a is directed toward the paper feed roller pair 17. The leading end 14a is sent out to the printing unit by the pair of paper feed rollers 17.

The paper feed roller pair 17 includes a capstan roller 18 and a pinch roller 19 which presses against the capstan roller 18. The capstan roller 18 is driven to rotate by a motor 20.

After printing, the tip holding device 21 moves the tip 14
a is returned to the vicinity of the paper feed roller 17,
And the leading end 14a is returned to the recording paper roll 12 in that state.

Downstream of the roll chamber 11, a pair of transport rollers 2
2 are provided. The transport roller pair 22 includes a capstan roller 23 and a pinch roller 24, and the capstan roller 23 is driven to rotate by the motor 20. The motor 20 is connected to the controller 2 via a driver 25.
6 is controlled. The controller 26 controls the driving of the motor 20 to reciprocate the recording paper 14 in the right paper feed direction and the left rewind direction by the drive roller 15, the transport roller pair 17, and the transport roller pair 22. I do.

A thermal head 27 and a platen roller 28 are disposed between the roll chamber 11 and the transport roller pair 22 so as to sandwich the transport path. Thermal head 2
Reference numeral 7 is disposed below the transport path, and includes a heating element array 27a in which a plurality of heating elements are arranged. The heating element array 27a extends in a direction orthogonal to the direction in which the recording paper 14 is conveyed, as is well known. The platen roller 28 is disposed above the transport path at a position facing the heating element array 27a. The thermal head 27 is movable in the vertical direction, and is urged by a spring (not shown) in a direction in which the thermal head 27 is pressed against the platen roller 28.

A yellow fixing lamp 29 and a magenta fixing lamp 30 are provided downstream of the conveying roller pair 22. As the yellow fixing lamp 29, a rod-shaped ultraviolet lamp having an emission peak of approximately 420 nm is used.
The emission peak of the magenta fixing lamp 30 is approximately 365 nm.
UV lamp.

A cutter 31 is provided downstream of the magenta fixing lamp 30. The cutter 31 cuts the recording paper 14 drawn from the recording paper roll 12 into a sheet. The cut recording paper 14 is discharged out of the printer through the recording paper entrance 32. A tip detection sensor 33 is provided near the roll chamber 11. The leading edge detection sensor 33 detects the passage of the leading edge 14a of the recording paper 14 and sends a detection signal to the controller 26. Controller 26
Controls the tip holding device 21 based on the detection signal from the tip detection sensor 33.

As shown in FIGS. 2 and 3, the front-end holding device 21 is disposed on the side of the sheet feeding roller pair 17. The tip holding device 21 includes a motor 39, gears 40 and 41, a shaft 42,
It comprises a support arm 43, a clip 44 for holding the distal end, and a cam 45. The motor 39 is driven by the controller 26 via the driver 46. Further, a gear 40 is provided at a distal end portion of the drive shaft 39a of the motor 39.

The sector gear 41 is arranged so as to mesh with the gear 40, and the driving force of the motor 39 is transmitted to the sector gear 41. The sector gear 41 is formed in a substantially fan shape, and rotates around a mounting shaft 41a provided integrally. A mounting shaft 41b is also provided on the side of the sector gear 41 facing the recording paper roll 12, and a shaft 42 is fixed to the mounting shaft 41b.

The shaft 42 has a hole 42a to be inserted into the mounting shaft 41b on one side, and a mounting portion 42b on the other side. Mounting part 42b
Is pressed into the mounting hole 43a of the support arm 43, whereby the support arm 43 rotates integrally with the rotation of the sector gear 41.

A mounting hole 43b is provided at the tip end of the support arm 43.
The shaft 44a of the distal end holding clip 44 is rotatably mounted in the mounting hole 43b. The tip holding clip 44 includes two clip pieces 47a and 47b rotatably attached to a shaft 44a, and is displaced between an open state and a closed state. And the tip holding clip 44
When the support arm 43 is rotated, it passes through a retreat position where the recording paper 14 retreats from the conveyance path of the recording paper 14 shown in FIG. 4 and a position where the leading end 14a of the recording paper 14 shown in FIGS.
As shown in FIG. 7, it rotates between the holding position near the driving roller 15. The moving speed of the front end holding clip 44 is slightly faster than the moving speed (rewinding speed) of the color thermosensitive recording paper 14.

A spring 4 is provided on the rear end side of the front end holding clip 44.
The distal end portion of the clip 44 is always closed by the bias of the spring 48. Two cam followers 44b are provided on the side surfaces of the clip pieces 47a and 47b, and the posture and opening / closing of the tip holding clip 44 are adjusted by the cam followers 44 being guided by the cams 45.

The cam 45 is disposed along the movement path of the distal end holding clip 44, and includes a pair of cam pieces 45a and 45b to which the retracted position side of the distal end holding clip 44 is connected. Further, cam grooves 45c and 45d are provided on the retreat position side.
The guide 45e is formed so as to form. When the distal end holding clip 44 moves to the retracted position, as shown in FIG.
Enter 5d. These cam grooves 45c and 45d are
Pushing the cam follower 44b in the approaching direction to open the tip holding clip 44 in the open state.

Cam follower 4 of clip 44
4b comes to the leading end side of the guide 45e, enters the conveying path with the leading end side of the leading end holding clip 44 opened, and the recording paper 1
4 can be nipped. Cam follower 4
Since the space between the pair of cam pieces 47a and 47b increases near the position where the recording paper 4b comes out of the cam grooves 45c and 45d, the tip holding clip 44 is closed by the spring 48, and the recording paper 14 is nipped with the recording paper 14 nipped. Roll 1
2 to the outer circumference.

The controller 26 starts driving the motor 39 in response to the detection signal of the tip 14a from the tip detection sensor 33. Considering the movement time of the distal end 14a from the detection position of the distal end detection sensor 33 to the position where the distal end 14a is nipped by the distal end holding clip 44, and the position of the position where the distal end holding clip 44 can be nipped from the retracted position. The controller 26 drives the motor 39 at a speed corresponding to the timing at which the tip 14a reaches the position where the tip 14a is nipped.

Next, the operation of the above configuration will be described. If the recording paper is used up during the previous printing, the recording paper roll is not reversed.
4 is set to the retracted position shown in FIG. The loading lid (not shown) is opened, and a new recording paper roll 12 is loaded into the roll chamber 11. At this time, the leading edge 1 of the recording paper 14
4a is positioned above the drive roller 15.

When a print key is operated after designating an image to be printed, the controller 26
5, the motor 20 is rotated. The motor 20 includes a driving roller 15, a sheet feeding roller pair 17, and a conveying roller pair 22.
To rotate. The recording paper roll 1 is driven by the driving roller 15.
2 is rotated forward, the leading end 14a of the recording paper 14 is separated by the separation plate 16 and enters the conveyance path.

The leading end 14a of the recording paper 14 moves on the conveyance path in the paper feeding direction and is nipped by the paper feeding roller pair 17.
The paper feed roller pair 17 pulls out the recording paper 14 from the recording paper roll 12 in place of the drive roller 15, passes the thermal head 27, and conveys the paper toward the conveyance roller pair 22. When the leading end 14a reaches between the conveying roller pair 22,
The controller 26 stops the motor 20. The pinch roller 24 of the transport roller pair 22 moves to nip the leading end 14a.

The controller 26 rotates the motor 20 again to rotate the recording paper 14 at a constant speed in the paper feeding direction.
At the same time, the yellow fixing lamp 29 is turned on, and the thermal head 27 is moved toward the recording paper 14 so that the heating element array 27 a is pressed against the recording surface of the recording paper 14. In the thermal head 27, each heating element is energized according to the yellow image data, and color-records the yellow image line by line. When the portion where the yellow image was recorded passed over the yellow fixing lamp 29, ultraviolet light having an emission peak of 420 nm was irradiated, and the yellow image was fixed.

When the recording and fixing of the yellow image are completed, the controller 26 retracts the thermal head 27 and turns off the yellow fixing lamp 29. next,
The controller 26 rotates the motor 20 to return the recording paper 14 in the rewind direction while winding the recording paper 14 around the outer periphery of the recording paper roll 12.

The leading end 14a of the recording paper 14 is
When the motor 20 returns to the position 2, the motor 20 starts normal rotation. At the same time, the magenta fixing lamp 30 is turned on. The thermal head 27 is pressed against the recording paper 14 and causes each heating element to generate heat in accordance with the magenta image data, so that the magenta image
Color recording is performed line by line. The portion where the magenta image is recorded is subjected to fixing processing with ultraviolet light having an emission peak emitted from the magenta fixing lamp 30 at 365 nm.

When the recording and fixing of the magenta image are completed, the recording paper 14 is rewound and then conveyed again in the paper feeding direction. During this conveyance, a cyan image is recorded line by line. After the recording of the cyan image, the cutter 31 operates to cut off the recorded portion and discharge it from the recording paper entrance 32. Thus, one print is completed.

If the recording surface of the recording paper 14 is left as it is exposed, the coloring characteristics are changed by the influence of moisture. Therefore, after printing is completed, the controller 26
Is reversed, and the recording paper 14 is wound around the outer periphery of the recording paper roll 12.

When the rewinding of the recording paper 14 is started, as shown in FIG. 4, the front end holding clip 44 is set at the retracted position. In this retracted position, the cam follower 44b is located on the inner side of the cam grooves 45c and 45d, and the front end holding clip 44 is in an open state.

When the leading end 14a of the recording paper 14 is detected by the leading end detection sensor 33, the controller 26
, The motor 39 is rotated. This motor 39
The support arm 43 is rotated clockwise in FIG. 4 via the sector gear 41. By the rotation of the support arm 43, the clip 44 for holding the distal end moves toward the transport path while being guided by the cam 45.

As shown in FIG.
When the cam follower 44b comes to the distal end side of the guide 45e, it enters the transport path with the distal end of the distal end holding clip 44 opened. At this point, the leading end of the leading end holding clip 44 is behind the leading end 14a of the recording paper 14. Since the moving speed of the front end holding clip 44 is slightly faster than the conveyance speed of the recording paper 14, the front end holding clip 44
And place it between the open ends.

When the tip holding clip 44 further moves,
The cam follower 44b comes out of the cam grooves 45c and 45d. Since the interval between the pair of cam pieces 47a and 47b increases from this vicinity, as shown in FIG.
4 is closed by the spring 48, and the leading end 14a of the recording paper 14 is nipped.

When the leading-end holding clip 44 moves to the holding position shown in FIG.
Reverse rotation stops. The rewinding of the recording paper 14 is completed with the leading end 14a of the recording paper 14 being nipped by the leading end holding clip 44. In this state, since the recording paper 14 is tightly wound, the recording surface is not affected by moisture.

When printing is performed again, the motor 2
The recording paper roll 12 is rotated forward by 0, and the leading end 14a of the recording paper 14 is sent out. At the same time, since the motor 39 rotates, the distal end holding clip 44 rotates counterclockwise in FIG. The leading edge holding clip 44 moves so as to pull out the recording paper 14, releases the nip of the leading end 14 a of the recording paper 14 near the paper feed roller pair 17, and
Is moved to the retreat position shown in FIG. On the other hand, the recording paper 14 is sent to the printing unit by the paper feed roller pair 17 after the tip holding clip 44 comes off, and the printing process is performed. Since the front end holding clip 44 guides the front end 14a, the recording paper 14 is reliably separated from the recording paper roll 12 even when the recording paper 14 is thin.

In the above embodiment, a color thermal printer using color thermal recording paper has been described as an example. However, the present invention is also used in a photographic printer for printing on photographic paper and other printers using a recording paper roll. be able to.

In the above embodiment, the color thermal printer 1
The example in which the recording paper roll 12 is loaded into the roll chamber 11 of the recording medium 0 has been described.
This paper feed magazine may be loaded in the printer. In this case, the front end holding device 20 is provided in the paper feed magazine.

[0046]

As described above, according to the leading end holding device of the present invention, the leading end holding clip for nipping the leading end of the recording paper is provided. Never lose track. This prevents the entry of moisture by tightly winding the recording paper around the recording paper roll, and eliminates the need for the sensor to detect the leading end by reversing the recording paper roll when feeding the leading end. This makes it possible to reduce the cost by omitting a complicated leading edge detecting device, and to shorten the paper feeding time by the time required for the reverse rotation of the recording paper roll.

Further, since the front end holding clip has a simple structure, it is possible to avoid an increase in the cost of the printer.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating a configuration of a color thermal printer.

FIG. 2 is a perspective view of the inside of a roll chamber.

FIG. 3 is an exploded perspective view of the tip holding device.

FIG. 4 is an explanatory diagram showing a state in which a clip for holding the distal end is set to a retracted position.

FIG. 5 is an explanatory diagram showing a state when the leading end holding clip sandwiches the leading end of the recording paper.

FIG. 6 is an explanatory diagram showing a state in which a recording paper front end clip nips the front end of the recording paper.

FIG. 7 is an explanatory view showing a state in which a front end holding clip is set to a holding position.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Color thermal printer 11 Roll room 14 Recording paper 15 Drive roller 38 Tip holding device 43 Support arm 44 Tip holding clip 45 Cam 47a, 47b Clip piece

Claims (4)

[Claims] 1. A recording paper roll is rotated forward at the time of paper feeding, and the leading end of the recording paper wound in a roll is sent out onto a conveyance path. After printing, the recording paper roll is reversed to cause the leading end of the recording paper to become a recording paper recording paper. In a printer adapted to return to the outer periphery of the roll, a tip holding clip displaced between a closed state for holding the leading end of the recording paper and an open state for allowing the leading end of the recording paper to be taken in and out; When the roll rotates forward, the tip holding clip is moved from the first position close to the recording paper roll toward the second position away from the recording paper roll, and when the recording paper roll rotates in the reverse direction. Clip moving means for moving the front end holding clip from the second position toward the first position, and closing the front end of the recording paper by closing the front end holding clip when the front end holding clip is at the first position. Let the first From the second position
When moving away from the conveyance path in the middle of the movement to the position, the front end holding clip is displaced from the closed state to the open state to release the front end of the recording paper, and the front end holding clip is at the second position. A clip for displacing the leading end holding clip from the open state to the closed state and holding the leading end of the recording paper when the opening state is set and the transport path is moved halfway from the second position to the first position. An opening / closing means is provided, the recording paper leading end holding device. 2. The clip for holding the distal end comprises a pair of clip pieces movable in opposite directions about a shaft, and a spring for urging these clip pieces to a closed state. 2. The recording paper leading edge holding device according to claim 1, wherein: 3. The clip moving means includes a support arm having one end attached to a shaft of a clip for holding the distal end, and a motor for rotating the arm around the other end of the support arm. 3. The recording paper leading edge holding device according to claim 2. 4. The clip opening / closing means is disposed along a pair of pins provided on each clip piece and a movement locus of these pins, and pushes each pin in the opposite direction to open the clip holding the tip. 4. The apparatus according to claim 3, further comprising a cam.