JPH09277649A - Cleaning brush attaching apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the fluctuations in feed load caused by a platen roller. SOLUTION: A brush member 38 having a brush 41 brought into contact with the outer periphery thereof is arranged to a platen roller 14 revolved so as to follow the reciprocating movement of recording paper. The brush member is supported so as to be freely movable between the position pressing the brush 41 to the outer periphery of the platen roller 14 by a support means 39 and the retraction position retracted from the pressing position and energized toward the pressing position by the energizing force of a spring 44. When the rotary direction of the platen roller 14 is changed over, the brush member 38 is moved toward the retraction position against the energizing force of the spring 44 by the replusing force generated in the brush 41 and, if the bristles of the brush 41 are arranged along the rotary direction of the platen roller 14, the brush 41 is again moved toward the pressing position by the energizing force of the spring 44.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for attaching a cleaning brush for cleaning a recording paper and a conveying roller for conveying the recording paper, which is used in a printer, a copying machine or the like.

[0002]

2. Description of the Related Art For example, in a color thermosensitive printer, a color thermosensitive recording paper in which at least three kinds of thermosensitive coloring layers such as a cyan thermosensitive coloring layer, a magenta thermosensitive coloring layer and a yellow thermosensitive coloring layer are sequentially laminated on a support. A reciprocating system is known in which a full-color image is printed in the recording area in a three-color frame sequence by reciprocating.

In this color thermal printer, the color thermal recording paper is reciprocated by a pair of conveying rollers, which are arranged beside the thermal head and are composed of an upper nip roller and a lower capstan roller, when printing. While the color thermosensitive recording paper is moving, the thermal head is shifted to the recording position, and the color thermosensitive recording paper is heated while being pressed against the color thermosensitive recording paper between the platen roller and the color thermosensitive recording paper to record color images.

Since the recording paper is pressed against the platen roller by the thermal head, paper dust, dust and the like of the recording paper adhere. Therefore, in order to remove the paper dust, dust, and the like by utilizing the static elimination effect, the conductive straight brush is fixed in contact with the platen roller.

[0005]

However, in the above-mentioned printer, since the platen roller rotates in the forward and reverse directions due to the reciprocal movement of the color thermosensitive recording paper, the brush contacting the platen roller at the time of switching the rotational direction. The fur coat temporarily bends and turns into an opposite eye, and a load is applied to the rotation of the platen roller until the fur coat bends along the rotation direction of the platen roller. Due to this load, the rotation of the platen roller becomes non-uniform, the feeding of the recording paper conveyed by the conveying roller pair is fluctuated, and there is a possibility that density unevenness, color misregistration, or the like occurs.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a cleaning brush attaching device which prevents the fluctuation of the conveyance load caused by the bending of the brush.

[0007]

In order to solve the above problems, the cleaning brush attaching device according to claim 1,
Outer periphery of a roller for transporting the recording paper that rotates in the forward and reverse directions, or a brush member in which a brush is in contact with one surface of the recording paper that transports in the forward and reverse directions, and the brush, the outer periphery of the roller or the recording paper. A support means for movably supporting the brush member between a pressing position for pressing the brush member toward the outer surface and a position away from the pressing position, and a biasing means for biasing the brush member toward the pressing position. is there. According to this, the repulsive force of the brush generated when the rotation direction of the roller is switched or when the recording paper is switched in the transport direction can be absorbed by the elastic deformation of the biasing means. Does not cause load fluctuations in the transportation of paper.

Further, in the cleaning brush attaching apparatus according to the second aspect of the present invention, since the supporting means is rotatably attached, the repulsive force of the brush can be absorbed by the elastic deformation of the urging means and the rotation of the supporting means. it can.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1 showing the internal structure of a color thermal printer 9, a color thermal recording paper 12 sent from a paper feed cassette 11 by a paper feed roller 10 passes through a guide plate 13 along a vertical direction. Be transported. A platen roller 14 and a thermal head 15 are arranged to face each other in this conveyance path, and a conveyance roller pair 16 is arranged above them.
Is arranged. The color thermosensitive recording paper 12 is fed between the platen roller 14 and the thermal head 15 and then nipped by the conveying roller pair 16. The conveying roller pair 16 has a rear end of the color thermosensitive recording paper 12 and the paper feeding roller 10.
It is provided at a position where the tip of this is nipped when it is removed from.

The nip roller 17 of the carrying roller pair 16 is movable in a direction orthogonal to the carrying path.
When the color thermosensitive recording paper 12 is conveyed, it is moved toward the capstan roller 18, and the capstan roller 18 is moved.
The color thermosensitive recording paper 12 is sandwiched between and. Simultaneously with the movement of the nip roller 23, the thermal head 15 moves the shaft 2
It rotates clockwise around 0 to press the heating element 15a against the color thermosensitive recording paper 12.

As is well known, the thermal head 15 has a large number of heating elements 15a arranged in a line in a direction orthogonal to the transport direction of the color thermosensitive recording paper 12, and each heating element 15a has a color and a pixel to be recorded. Generates heat energy according to the concentration of.

The color thermosensitive recording paper 12 is, as is well known,
On a support, a cyan thermosensitive coloring layer, a magenta thermosensitive coloring layer, a yellow thermosensitive coloring layer, and a protective layer are sequentially provided. Each of these thermosensitive coloring layers is provided from the surface in the order of thermal recording. For example, when thermal recording is performed in the order of magenta, yellow, and cyan, the yellow thermosensitive coloring layer and the magenta thermosensitive coloring layer are combined. The positions are swapped. As the support, an opaque coated paper or a plastic film is used, and when an OHP sheet is manufactured, a transparent plastic film is used.

The cyan thermosensitive coloring layer contains an electron-donating dye precursor and an electron-accepting compound as main components, and develops cyan when heated. The magenta thermosensitive coloring layer contains a diazonium salt compound having a maximum absorption wavelength of about 365 nm, and a coupler which reacts with the diazonium salt compound to develop magenta. When this magenta thermosensitive coloring layer is irradiated with ultraviolet light near 365 nm after thermal recording, the diazonium salt compound is photolyzed and loses its coloring ability. The yellow thermosensitive coloring layer contains a diazonium salt compound having a maximum absorption wavelength of about 420 nm, and a coupler that thermally reacts with the diazonium salt compound to develop yellow. When the yellow thermosensitive coloring layer is irradiated with ultraviolet rays near 420 nm, it is light-fixed and loses its coloring ability.

An optical fixing device 30 for yellow is provided on the downstream side of the feed roller pair 16 in the forward feed (upward feed in the drawing).
Is arranged. The yellow optical fixing device 30 includes a yellow ultraviolet lamp 31 and a reflector 32. On the yellow optical fixing device 30, magenta optical fixing devices 33 are arranged side by side. The magenta optical fixing device 33 includes a magenta ultraviolet lamp 34 and a reflector 35.

The yellow ultraviolet lamp 31 radiates ultraviolet rays having an emission peak of about 420 nm to optically fix the yellow thermosensitive coloring layer, and the magenta ultraviolet lamp 34 emits ultraviolet rays having an emission peak of about 365 nm to generate magenta thermosensitive coloring. Perform optical fixing of the layer.

The platen roller 14 is rotatably arranged around a shaft 37, and rotates following the transfer of the color thermosensitive recording paper 12. On the opposite side of the platen roller 14 from the side on which the thermal head 15 is arranged, a brush member 38 for removing paper dust, dust and the like adhering to the outer periphery of the platen roller is supported by a supporting means 39.

As shown in FIG. 2, the brush member 38 comprises a holding portion 40 and a brush 41. Holding part 40
Is a thin plate having a length slightly longer than the length along the axial direction of the platen roller 14, and is made of a conductive material. The brush 41 is made of a conductive material, and on the surface of the holding portion 40 facing the platen roller 14,
Many are planted along the longitudinal direction. This holder 40
Is grounded to the power supply ground inside the thermal printer 9 or to the frame by an electric wire 40c.

The supporting means 39 movably supports the brush member 38 between a pressing position where the brush 41 is pressed against the outer periphery of the platen roller 14 and a retracted position where the brush 41 is retracted. The supporting means 42 and the pair of springs 43 are provided. , 44 and a pair of mounting screws 45, 46. The supporting means 42 has a cross-sectional shape in which a long piece 42a and a short piece 42b form an L shape, and bed portions 42c and 42d are formed on the long piece 42a by raising both sides in the longitudinal direction by one step.

A brush 41 is attached to the bed portions 42c and 42d.
Slotted holes 42e and 42f are formed along the outer circumference of the platen roller 14 along the direction of pressing. The mounting screws 45 and 46 are screwed into the screw holes 40a and 40b formed in the holding unit 40 through the elongated holes 42e and 42f with a tightening force that allows the holding unit 40 to move.
The pair of springs 43 and 44 are inserted on both sides between the holding portion 40 and the short piece 42b of the supporting means 42 and uniformly urge the brush member 38 toward the pressing position. These springs 4
As 3, 44, those having a biasing force smaller than the maximum repulsive force of the brush 41 generated when the platen roller 14 is switched in the rotation direction are used.

Next, the operation of the above embodiment will be described.
When a print start switch (not shown) is operated, the color thermosensitive recording paper 12 at the top of the paper feed cassette 11 is sent out along the guide plate 13 by the paper feed roller 10 and directed toward the conveyance roller pair 16. Be transported. When the leading end of the color thermosensitive recording paper 12 is fed between the nip roller 17 and the capsten roller 18 of the conveying roller pair 16, the color thermosensitive recording paper 12 is sandwiched between them. At the same time, the thermal head 15 rotates clockwise around the mounting shaft 20, and the heating element 15 a presses the color thermosensitive recording paper 12 on the platen roller 14.

The color thermosensitive recording paper 12 has a pair of conveying rollers.
6 is conveyed in the forward direction. In this state,
As shown in (A), since the color thermosensitive recording paper 12 is being transferred in the upward direction, the platen roller 14 is attached to the shaft 3
Rotate clockwise around 7. The bristles 41 of the brush 41 are aligned along the rotation direction of the platen roller 14, and the brush member 38 is moved to the pressing position by the bias of the springs 43 and 44.

Since the holding portion 40 is connected to the ground, static electricity generated on the outer circumference of the platen roller 14 flows to the ground via the brush 41 and the holding portion 40 to remove paper dust, dust, and the like. It can be easily removed by simply pressing the brush 41.

When the leading edge of the recording area reaches the heating element 15a while the color thermosensitive recording paper 12 is being conveyed, each heating element 15a generates thermal energy corresponding to each pixel of the yellow image, and the yellow thermosensitive coloring layer has a yellow color. The image is thermally recorded line by line. When recording each pixel, each heating element 15a supplies to the color thermosensitive recording paper 12 bias thermal energy for bringing the yellow thermosensitive coloring layer into a state immediately before coloring and gradation expression thermal energy corresponding to the coloring density. give.

At the time of yellow thermal recording, the yellow ultraviolet lamp 31 is turned on. The 420 nm ultraviolet light emitted from the yellow ultraviolet lamp 31 is reflected by the inner surface of the reflector 32 and irradiates the color thermosensitive recording paper 12 in a slit shape. Since the color thermosensitive recording paper 12 is fed at a constant speed, each portion in the recording area is irradiated with a constant amount of light so that the yellow thermosensitive recording layer 12 does not develop yellow during thermal recording of the next magenta thermosensitive coloring layer. The coloring layer is fixed.

When the last line of the recording area of the color thermosensitive recording paper 12 is recorded, the driving of the thermal head 15 is stopped. At the same time, the thermal head 15 rotates counterclockwise around the shaft 20 to release the pressure on the color thermosensitive recording paper 12. At this time, since the pair of conveying rollers 16 is continuously rotating, yellow fixing by the fixing device 30 is continuing. Then, when the rear end of the color thermosensitive recording paper 12 is in a state of being nipped by the pair of conveying rollers 16,
The conveying roller pair 16 is stopped, and at the same time, the yellow ultraviolet lamp 31 is turned off.

After the conveying roller pair 16 is once stopped, it is rotated in the reverse direction to convey the color thermosensitive recording paper 12 in the opposite direction. When the color thermal recording paper 12 is conveyed in the opposite direction,
The platen roller 14 rotates counterclockwise about the shaft 37 as shown in FIG. When the rotation direction of the platen roller 14 is switched, the tip of the brush 41 hits the outer periphery of the platen roller 14 and a repulsive force is generated in the brush 41. This repulsive force causes the brush member 38 to move the springs 43, 4
It moves toward the retracted position against the bias of 4. Thereby, the repulsive force of the brush 41 is absorbed by the compression of the springs 43 and 44, so that the platen roller 14 is not subjected to load fluctuation.

After that, as shown in FIG. 6C, the brush 41 bends in the direction along the rotation direction of the platen roller 14, so that the repulsive force of the brush 41 decreases.
The holding portion 40 moves toward the pressing position by the bias of the springs 43 and 44. Then, when the front end of the color thermosensitive recording paper 12 is nipped by the conveying roller pair 16, the conveying roller pair 16 is temporarily stopped and then rotated forward to move the color thermosensitive recording paper 12 in the forward direction. Transport. Even when the rotation direction of the platen roller 14 is switched at this time, the brush member 38 moves toward the retracted position against the bias of the springs 43 and 44 by the repulsive force of the brush 41 as described above. The load on the roller 14 is not changed.

Simultaneously with the forward rotation of the conveying roller pair 16, the thermal head 15 returns to the thermal recording position again, and the recording paper 12 is conveyed in the forward direction to reach the head position of the recording area, whereby the thermal head 15 magenta. Thermal recording is performed by applying heat energy according to a magenta image to the thermosensitive coloring layer.
In addition, the magenta UV lamp 3 is synchronized with this thermal recording.
4 is turned on.

With this magenta ultraviolet lamp 34,
The near-ultraviolet rays near about 365 nm are color thermosensitive recording paper 12
To fix the magenta thermosensitive coloring layer so that magenta does not develop during the subsequent thermal recording of the cyan thermosensitive coloring layer.

When the forward end of the color thermosensitive recording paper 12 is nipped by the conveying roller pair 16, the conveying roller pair 16
Stop / reverse is started. At the same time, the magenta ultraviolet lamp 34 is turned off, and the thermal head 15 is retracted.

The color thermosensitive recording paper 12 is returned until the rear end of the color thermosensitive recording paper 12 in the opposite direction is nipped by the conveying roller pair 16, and then the conveying roller pair 16 is normally rotated again.
A cyan image is thermally recorded line by line on the cyan thermosensitive coloring layer by the thermal head 15. Also at this time, as described above, the repulsive force of the brush 41 causes the brush member 38 to move toward the retracted position against the bias of the springs 43 and 44, so that the platen roller 14 is not subjected to load fluctuation.

When thermal recording is performed on all the thermosensitive coloring layers,
The pair of transport rollers 16 continues to rotate and sends the color thermosensitive recording paper 12 toward the paper discharge path 50 shown in FIG.
The color thermosensitive recording paper 12 sent in is ejected by a pair of ejection rollers 5.
After being nipped at 1, the sheet is discharged to the sheet discharge tray 53 by the rotation of the roller pair 51. A full-color image is recorded on the discharged color thermosensitive recording paper 12. This image is recorded as a clear image in which no color misregistration or density unevenness has occurred due to a change in the conveyance load of the platen roller 14.

FIG. 4 shows another embodiment in which the supporting means 60 is rotatably mounted about the shaft 59. In the supporting means 60, the shaft 59 is located on the axis passing through the center of the rotating shaft 37 of the platen roller 14, and the brush 41 is rotated by the pair of springs 61 and 62 having the same urging force. It is kept in a neutral position on the axis connecting to and.

When the platen roller 14 is rotating clockwise, a force along the rotation direction of the platen roller 14 is applied to the brush 41, and the supporting means 60 is urged clockwise about the shaft 59. It As a result, the supporting means 60 rotates in the clockwise direction against the bias of the spring 61, and the biasing force of the contracted spring 61 and the biasing force of the expanded spring 62 and the platen roller acting on the brush 41 are applied. By being balanced with the rotational force of 14, the state shown in FIG. 4 (A) is maintained.

When the rotation direction of the platen roller 14 is switched, a force along the rotation direction of the platen roller 14 is applied to the brush 41, and a repulsive force is generated in the brush 41. Also in this embodiment, since the biasing force of the springs 43 and 44 is smaller than the repulsive force of the brush 41, this repulsive force causes the brush member 38 to move to the spring 4 as shown in FIG. 4B.
While being linearly moved toward the retracted position against the bias of 3,44, the support means 60 rotates about the shaft 59 to the neutral position.

When the platen roller 14 continues to rotate in the counterclockwise direction, the support means 60 is urged beyond the neutral position and further in the clockwise direction about the shaft 59. The repulsive force of the brush 41 is maximized when the support means 60 is in the neutral position, and is reduced again when the support means 60 is exceeded. For this reason,
When the rotation of the support means 60 exceeds the neutral position, the brush member 3
8 is moved toward the pressing position by the bias of the springs 43 and 44. Then, in addition to the contracted biasing force of the spring 62, the biasing force of the expanded spring 61 and the rotational force of the platen roller 14 acting on the brush 41 are balanced to maintain the state shown in FIG. 4C. Be drunk According to this, since the support means 60 is rotatably attached in addition to the linear movement of the brush member 40, the repulsive force of the brush 40 is absorbed only by the linear movement of the brush member 40. Furthermore, it is possible to suppress fluctuations in the rotational load of the platen roller 14 to a low level.

A compression spring 4 is used as the urging means in each of the above embodiments.
Although 3 and 44 are used, elastic materials such as rubber and sponge may be used instead. Further, as the roller cleaned by the brush member 38, the thermal head 1
Not limited to the platen roller 37 arranged to face the sheet 5, it may be brought into contact with, for example, a conveying roller or the like for conveying the recording paper regardless of the driving and driven rollers. Further, not limited to the roller, the brush member 38 may be directly pressed against the recording surface of the recording paper or the back surface thereof to remove the paper dust or dust attached to the recording paper. Further, the present invention can be applied not only to the thermal printer but also to other printers, copying machines, facsimiles and the like.

[0038]

According to the present invention, the repulsive force of the brush generated when the rotation direction of the roller is switched or when the recording paper is switched in the transport direction can be absorbed by the biasing means. Alternatively, it is possible to prevent a load change from being exerted on the conveyance of the recording paper, and it is possible to surely eliminate a defect caused by the change in the conveyance load. Then, this effect becomes greater as the recording paper having a larger size in the direction orthogonal to the transport direction is used. Further, since the pressing force of the brush can be regulated by the urging force of the urging means, the brush member can be mounted roughly and the productivity can be improved.
Further, in the invention according to claim 2, since the support means is rotatably attached, the repulsive force of the brush can be absorbed by the rotation of the support means in addition to the elastic deformation of the biasing means. It is possible to further prevent fluctuations in the transport load as compared with those described above.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a color thermal printer embodying the present invention.

FIG. 2 is an exploded perspective view showing a configuration of a brush member and a supporting means.

FIG. 3 is an explanatory view showing an operation of a brush attaching means.

FIG. 4 is an explanatory view showing the operation of another embodiment in which the supporting means is rotatably attached.

[Explanation of symbols]

 12 Color Thermal Recording Paper 14 Platen Roller 15 Thermal Head 16 Conveyor Roller Pair 38 Brush Member 39 Support Means 40 Holding Part 41 Brush 42,60 Support Means 43,44,61,62 Spring 45,46 Mounting Screw

Claims (2)

[Claims] 1. An outer circumference of a roller for transporting a recording paper that rotates in forward and reverse directions, or a brush member in which a brush abuts on one surface of a recording paper that is transported in forward and reverse directions, and the brush has an outer circumference of the roller. Or, a supporting means for movably supporting the brush member between a pressing position for pressing the recording paper toward the outer surface and a position away from the pressing position, and a biasing means for biasing the brush member toward the pressing position. An apparatus for attaching a cleaning brush, which is characterized by being provided. 2. The cleaning brush according to claim 1, wherein the support means is attached so as to be rotatable in a rotation direction of the roller or a direction along a recording paper conveyance direction. Mounting device.