JP7206868B2 - Print medium conveying device and printing device - Google Patents

Description

The present invention relates to a print medium conveying device and a printing device.

Conventionally, in a printing apparatus for printing on cloth, an endless belt is used as a member for supporting and conveying the cloth, which is a printing medium, and water is sprayed on the conveying surface of the endless belt outside the conveying section of the cloth to clean it, followed by a water absorbing roller (wiping off). wiping with a roller) to remove moisture. This cleans the outer surface of the endless belt, restores the adhesiveness of the adhesive layer formed on the outer surface of the endless belt, and maintains the adhesive force for attaching the fabric (Patent Documents 1 and 2).
In Patent Document 1, a squeezing roller is provided in pressure contact with the water-absorbing roller to squeeze water from the water-absorbing roller, so that the water-absorbing roller can again absorb water from the endless belt.

JP-A-11-192694 Japanese Patent Application Laid-Open No. 2001-122486

However, even if a squeezing roller is provided that presses against the water absorbing roller and squeezes the water from the water absorbing roller, the water absorbing roller gradually absorbs water and approaches a saturated state, resulting in a decrease in water absorption. It is not canceled.
In the conventional technology, the water absorbing roller presses and rolls against the endless belt, and the squeezing roller presses and rolls against the water absorbing roller. being driven. Therefore, the squeezing operation can only be performed according to the driving of the endless belt while the water absorbing roller is in use. One is that the rotation speed and torque are constant. Also, if the pressure of the squeezing roller against the water absorbing roller is excessively increased, the water absorbing roller will not rotate and the same surface of the water absorbing roller will continue to hit the endless belt. .
In order to apply a moisture removing method to the water absorbing roller, which is different from the squeezing operation following the drive of the endless belt during use of the water absorbing roller, the water absorbing roller can be removed from the endless belt. However, during the period between removing the water absorbing roller and attaching the water absorbing roller, printing must be stopped, resulting in a decrease in productivity.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems in the prior art, and an object of the present invention is to quickly and effectively recover the water absorbency of a water absorbing roller without lowering the productivity of printing as much as possible. .

The invention according to claim 1 for solving the above problems is an endless belt that supports and conveys a print medium on its surface,
a cleaning device for cleaning the surface of the endless belt supporting the print medium with water;
a water absorbing roller that rolls in pressure contact with the surface and absorbs water adhering to the surface due to cleaning by the cleaning device;
a roller moving device that moves the water absorbing roller between a belt water absorbing position where the water absorbing roller is pressed against the surface and a belt separation position where the belt separates from the surface;
The roller moving device can be equipped with a plurality of the water absorbing rollers, and can replace one water absorbing roller at the belt water absorbing position with another water absorbing roller at the belt separation position ,
In the print medium conveying device, the water absorbing roller has a built-in heater .

The invention according to claim 2 is an endless belt that supports and conveys a print medium on its surface,
a cleaning device for cleaning the surface of the endless belt supporting the print medium with water;
a water absorbing roller that rolls in pressure contact with the surface and absorbs water adhering to the surface due to cleaning by the cleaning device;
a roller moving device that moves the water absorbing roller between a belt water absorbing position where the water absorbing roller is pressed against the surface and a belt separation position where the belt separates from the surface;
a moisture meter for measuring the moisture content of the water absorbing roller at the belt water absorbing position;
The roller moving device can be equipped with a plurality of the water absorbing rollers, and can replace one water absorbing roller at the belt water absorbing position with another water absorbing roller at the belt separation position,
The roller moving device is a print medium conveying device that moves the water absorbing roller related to the measurement result from the belt water absorption position to the belt separation position based on the measurement result of the moisture meter .

The invention according to claim 3 is an endless belt that supports and conveys a print medium on its surface;
a cleaning device for cleaning the surface of the endless belt supporting the print medium with water;
a water absorbing roller that rolls in pressure contact with the surface and absorbs water adhering to the surface due to cleaning by the cleaning device;
a roller moving device that moves the water absorbing roller between a belt water absorbing position where the water absorbing roller is pressed against the surface and a belt separation position where the belt separates from the surface;
a water removing device for removing water from the water absorbing roller at the belt divergence position,
The roller moving device can be equipped with a plurality of the water absorbing rollers, and can replace one water absorbing roller at the belt water absorbing position with another water absorbing roller at the belt separation position . A media transport device.

According to a fourth aspect of the invention, the water removal device has a squeeze roller that presses against the water absorption roller at the belt separation position, and a driving device that rotates the water absorption roller and the squeeze roller while they are in pressure contact with each other. 3. The print medium transport device according to 3.

The invention according to claim 5 is the print medium conveying device according to claim 4, wherein the roller moving device can arrange the water absorbing roller at a position separated from the endless belt and the squeeze roller.

The invention according to claim 6 comprises a control device for controlling the driving device,
The drive device is independent of the drive system of the endless belt,
6. The print medium conveying device according to claim 4, wherein the control device variably controls the driving rotation speed.

According to a seventh aspect of the invention, the roller moving device moves the water absorbing roller between the belt water absorbing position and the squeezed position where the squeezed roller is in pressure contact with the same driving device. 7. The print medium transport device according to 6.

The invention according to claim 8 is the print medium conveying device according to any one of claims 1 to 7 , wherein the roller moving device can be equipped with three or more of the water absorbing rollers.

The invention according to claim 9 is a printing medium transporting device according to any one of claims 1 to 8 ,
a print medium supply device that supplies a print medium to the surface of the endless belt in a section between the belt water absorption position and the cleaning device along the running direction of the endless belt;
a print head that prints on a print medium supported on the surface of the endless belt in the section.

ADVANTAGE OF THE INVENTION According to this invention, the water absorption of a water absorption roller can be rapidly and effectively restored, without reducing printing productivity as much as possible.

1 is a schematic diagram showing the main configuration of a printing apparatus according to a first embodiment of the invention; FIG. 1 is a perspective view showing parts of a roller moving device and a water removal device according to a first embodiment of the present invention; FIG. 1 is a perspective view showing parts of a roller moving device and a water removal device according to a first embodiment of the present invention; FIG. 1 is a perspective view showing parts of a roller moving device and a water removal device according to a first embodiment of the present invention; FIG. 1 is a schematic diagram showing the main configuration of a print medium conveying device according to a first embodiment of the present invention; FIG. FIG. 5 is a schematic diagram showing the main configuration of a print medium conveying device according to a second embodiment of the present invention; FIG. 10 is a schematic diagram showing the main configuration of a print medium conveying device according to a third embodiment of the present invention; FIG. 11 is a schematic diagram showing the main configuration of a print medium conveying device according to a fourth embodiment of the present invention;

An embodiment of the present invention will be described below with reference to the drawings. The following is one embodiment of the present invention and does not limit the present invention.

[First embodiment]
First, a first embodiment of the present invention will be described with reference to FIGS. 1 to 5. FIG.
The printing apparatus 1 of this embodiment includes a print head 2 , a print medium supply device 3 , and an endless belt type print medium transport device 10 .
A fabric is applied as the printing medium S. FIG. As the print head 2, an inkjet system that ejects ink onto the print medium S is applied.
The print medium conveying device 10 includes an endless belt 11, a cleaning device 12, water absorbing rollers R1 and R2, a roller moving device 14, and a water removing device 15 including a squeezing roller R5.
The endless belt 11 is wound between a plurality of rollers R11 and R12, and driven to run by rotation of at least one roller (R11).
The water absorbing roller R1 or R2 is pressed against the surface of the endless belt 11 at the belt water absorbing position P1.
The print medium supply device 3 supplies the print medium S to the surface of the endless belt 11 in a section between the belt water absorption position P1 and the cleaning device 12 along the running direction of the endless belt 11 . The printing medium supply device 3 presses the printing medium S unwound from an unillustrated unwinding roller against the surface of the endless belt 11 with a pressing roller R13. A layer of adhesive is formed on the surface of the endless belt 11, and the surface of the endless belt 11 is an adhesive surface. The print medium S pressed by the pressure roller R13 adheres to the surface of the endless belt 11 and is conveyed toward the print head 2 by the endless belt 11 running in synchronism with the print medium feeder 3 . After being printed by the print head 2, the print medium S is guided by the roller R14, stripped from the endless belt 11, dried, and then collected by being wound up by a winding roller.

The surface of the endless belt 11 after the print medium S has been peeled off is washed in the order of water injection from the injection nozzle 12a provided in the cleaning device 12, brushing by the brush roller 12b, and water injection from the injection nozzle 12c. After that, the adhering water droplets are dropped by the blade 12d. Further, the endless belt 11 runs, and water remaining after the blade 12d passes is absorbed by the water absorbing roller R1 at the belt water absorbing position P1.
A cycle in which the surface of the endless belt 11, which has been washed with water as described above and whose moisture has been removed, contacts the pressure roller R13 again to stick the print medium S thereon, and conveys the print medium S toward the print head 2. is executed.

As described above, the endless belt 11 supports and conveys the print medium S on its surface. The cleaning device 12 cleans the surface (outer surface) of the endless belt 11 that supports the printing medium S with water. The water absorbing roller R1 (R2) rolls against the surface of the endless belt 11 and absorbs water adhering to the surface after washing by the washing device 12 .

The roller moving device 14 moves the water absorbing roller R1 (R2) between the belt water absorbing position P1 and the belt separation position (position other than P1) separated from the surface of the endless belt 11 .
The roller moving device 14 in this embodiment can be equipped with a plurality of water absorbing rollers R1 and R2, one water absorbing roller R1 (R2) at the belt water absorbing position P1 and another water absorbing roller at the belt separation position R2 (R1) can be interchanged.
Therefore, if a water-absorbing roller R2 having sufficient water-absorbing power is installed as the water-absorbing roller R2 at the belt separation position shown in FIG. At the timing when the water absorption capacity increases and the water absorption capacity decreases, the roller moving device 14 replaces the water absorption roller R1 and the water absorption roller R2, so that the water absorption roller R2 having water absorption capacity is arranged at the belt water absorption position P1. be. In this manner, the water absorption of the water absorbing roller can be quickly and effectively recovered without lowering the printing productivity as much as possible.

In this embodiment, a water removal device 15 including a squeezing roller R5 is provided in order to remove water from the water absorption roller R2 at the belt separation position shown in FIG. 1 with sufficient water absorption.
The water removing device 15 includes a squeeze roller R5 and a water receiving tray 15a, and removes water from the water absorbing roller at the belt separation position. For this purpose, the water removal device 15 rotates the squeeze roller R5, which is in pressure contact with the water absorption roller (R2) at the belt divergence position (those of which, the squeeze position P2), and the water absorption roller (R2) and the squeeze roller R5 in pressure contact with each other. and a drive (motor M2).

Here, specific configuration examples of the roller moving device 14 and the water removal device 15 will be described with reference to FIGS.
The roller moving device 14 has a pair of rotating plates 14a and 14b. A pair of rotating plates 14a and 14b are supported by the equipment frame 16 so as to rotate parallel to the axis of the roller R11 and coaxially with each other. A pair of rotating plates 14a and 14b rotatably support both ends of water absorbing rollers R1 and R2 arranged parallel to the axis of roller R11. The rotating shafts of the water absorbing rollers R1 and R2 are radially the same distance away from the rotating shafts 14c of the pair of rotating plates 14a and 14b. In this embodiment, since the roller moving device 14 is equipped with two water absorbing rollers, the rotating shaft of one water absorbing roller R1 and the rotating shaft of the other water absorbing roller R2 are the rotating shafts of the pair of rotating plates 14a and 14b. They are arranged 180 degrees opposite to 14c.
In FIG. 2, the water absorbing roller R1 is located at the belt water absorbing position P1, and the water absorbing roller R2 is located at the squeeze position P2. provided on the opposite side.

The roller moving device 14 has a motor M1 for rotating the rotating plate 14a around the rotating shaft 14c. A stepping motor is applied as the motor M1, and the rotation of the motor M1 is transmitted to the spindle shaft 14d joined to the rotating plate 14a. Suitable transmission elements are, for example, timing belts and pulleys.
Detected members 14e and 14f rotating around a rotating shaft 14c together with the rotating plate 14b are provided so as to detect the phase of the water absorbing roller R1 and the phase of the water absorbing roller R2, which are detected by photointerrupters 14h and 14g. This detection mechanism may be provided on the rotating plate 14a side.
When the photointerrupter 14g detects the members to be detected 14e and 14f, one of the two water absorbing rollers R1 and R2 is at the belt water absorbing position P1 and the other is at the diaphragm position P2 (arrangements in FIGS. 1 and 2). .
When the photointerrupter 14h detects the members to be detected 14e and 14f, the two water absorbing rollers R1 and R2 are both positioned away from the endless belt 11 and the squeeze roller R5 (see FIGS. 3, 4 and 5). placement).
Therefore, by inputting the detection signals of the photointerrupters 14h and 14g into the control device for controlling the rotational phase of the motor M1, the control device can control the water absorption on the one hand and the arrangement of the diaphragm on the other hand (the arrangement shown in FIGS. 1 and 2). ) and a double release arrangement (arrangements in FIGS. 3, 4 and 5).
In this manner, the roller moving device can arrange the water absorbing roller R1 (R2) at the release position separated from the endless belt 11 and the squeeze roller R5. Moreover, when a plurality of water absorbing rollers are installed, all the water absorbing rollers can be arranged at the release position at the same time. As a result, when the water absorbing roller is not used for a long period of time, it is possible to avoid pressure contact between the water absorbing roller and other members, and to avoid deformation of the water absorbing material of the water absorbing roller.

As described above, the roller moving device 14 moves the water absorbing rollers R1 and R2 to the belt water absorbing position P1 and the squeeze position P2 in pressure contact with the squeeze roller R5 by the same driving device (motor M1).
This simplifies the structure and stabilizes the replacement operation of the water absorbing rollers R1 and R2 to the belt water absorbing position P1 and the throttle position P2.

Now, the water absorbing roller (R2 in FIG. 2) arranged at the throttle position P2 is transmission-connected to the motor M2. The connection/disengagement of the transmission depends on the frictional connection between the pulley 15b rotationally driven by the motor M2 and the pulley fixed to the spindle shaft of each water absorbing roller, but the configuration is arbitrary.
The motor M2 is a driving device that rotates the water absorbing roller (R2) and the squeezing roller R5 while they are in pressure contact with each other, and is independent from the driving system of the endless belt 11 (a driving motor for the endless belt 11 is provided separately). A DC motor, a brushless motor, or the like is applied as the motor M2, which is connected to a driver whose driving rotation speed is variable and a control device, and the control device controls the driving rotation speed variably.
Therefore, the squeezing of the water absorbing roller in the water removing device 15 is not performed by the squeezing operation following the driving of the endless belt 11 while the water absorbing roller is in use. The squeezing of the water absorbing roller in the water removing device 15 is performed by a driving source different from the driving source of the endless belt 11 when the water absorbing roller is not in use (during standby).
Therefore, it is easy to make the driving rotation speed variable. Also, a torque that is not restricted by the drive system of the endless belt 11 can be freely selected. Therefore, it is possible to design a diaphragm operation with a high degree of freedom, such as a long-term effective low-speed diaphragm operation and a short-term rapid diaphragm operation.
In addition, since it is sufficient if the water absorbing roller (R2) and the squeezing roller R5 can be rotated while being pressed against each other, it is possible to implement a configuration in which power is transmitted to the squeezing roller R5, and from the squeezing roller R5 to the water absorbing roller (R2). good.

In addition to the above configuration, a configuration in which heaters R1h and R2h are built in water absorbing rollers R1 and R2 as shown in FIG. 5 may be implemented. For example, after the water absorbing roller R1 (R2) is squeezed by the squeezing roller R5 and before it is arranged at the belt water absorbing position P1, the water absorbing material of the water absorbing roller R1 (R2) is dried by heating with the heater R1h (R2h). set up. As a result, water that cannot be completely removed by squeezing and dehydration can be removed, and sufficient drying can be performed.

Furthermore, in addition to the above configuration, as shown in FIG. 5, a configuration including a moisture meter 14i for measuring the moisture content of the water absorbing roller at the belt water absorbing position P1 may be implemented. In this case, the roller moving device 14 performs movement timing control to move the water absorbing roller according to the measurement result from the belt water absorbing position P1 to the throttle position P2 based on the measurement result of the moisture meter 14i. As a result, it is possible to appropriately control the timing of replacement of the water absorbing roller, avoid insufficient wiping of water from the endless belt 11, and maintain and improve print quality. As the moisture meter 14i, it is preferable to apply an optical moisture meter capable of non-contact measurement.

[Second embodiment]
As shown in FIG. 6, the second embodiment has a configuration in which the water removal device 15 is eliminated from the first embodiment, and the rest of the configuration is the same as that of the printing apparatus 1 of the first embodiment.
While one water absorbing roller is located at the belt water absorbing position P1, the water absorbing roller located at the belt divergence position P0 and after being used for absorbing water is replaced with a water absorbing roller having sufficient water absorbing power to be arranged at the belt water absorbing position P1. You can prepare a water absorbing roller with sufficient water absorbing power.
For example, as shown in FIG. 6, the water absorbing roller R1 after water absorption and use is moved from the belt water absorption position P1 to the belt separation position P0 by the roller moving device 14, and at the same time, the water absorption roller R2 with sufficient water absorption is moved to the belt separation position P0. to the belt water absorption position P1. At the belt divergence position P0, the water absorbing roller R1 after water absorption and use is replaced with a separately prepared water absorbing roller R3 having sufficient water absorbing power. After water absorption, the water absorption roller R1 is subjected to water absorption recovery treatment using a wringer, a dryer, or the like. The water absorbing roller after the water absorbing power recovery treatment is reused as a water absorbing roller with sufficient water absorbing power attached like the water absorbing roller R3 in FIG. Alternatively, the water absorbing roller R1 after water absorption and use is removed at the belt deviation position P0, and after water absorption recovery treatment is performed using a wringer, a dryer, etc., the water absorption roller R1 after the water absorption recovery treatment is moved to the roller moving device 14. Attach to
As described above, the roller moving device 14 can be equipped with a plurality of water absorbing rollers, and can replace one water absorbing roller at the belt water absorbing position with another water absorbing roller at the belt separation position. Therefore, by replacing the used water absorbing roller with a water absorbing roller with sufficient water absorbing power at the position where the belt is separated according to the above procedure, the water absorbing roller quickly and effectively absorbs water without reducing printing productivity as much as possible. sexuality can be restored.

[Third embodiment]
As shown in FIG. 7, the third embodiment has a configuration in which only one water absorbing roller is provided in the roller moving device 14 in contrast to the first embodiment. has the same configuration as One water absorbing roller R1 moves between a belt water absorbing position P1 and a squeeze position P2.
When one water-absorbing roller R1 is at the squeeze position P2, no water-absorbing roller is arranged at the belt water-absorbing position P1. , the water absorbing power of the water absorbing roller R1 can be recovered at an early stage, and the water absorbing roller R1 can be returned to the belt water absorbing position P1. As a result, the water absorbency of the water absorbing roller can be restored quickly and effectively without lowering printing productivity as much as possible.

[Fourth embodiment]
In the fourth embodiment, as shown in FIG. 8, the roller moving device 14 is equipped with three water absorbing rollers (R1, R2, R3) in contrast to the first embodiment. It has the same configuration as the printing apparatus 1 of one embodiment. At the same time, the water absorbing rollers are arranged at the belt water absorbing position P1, the squeeze position P2, and the release position P3. Further, the number of water absorbing rollers may be increased. Since there are three or more water absorbing rollers, the water absorbing rollers can be sequentially shifted to the water absorbing process at the belt water absorbing position P1, the squeezing process at the squeezing position P2, and the waiting process at the release position P3. The standby process at the release position P3 may be provided with a drying finishing process using a built-in heater of the water absorbing roller, an external heater, an external blower, or the like.
As described above, the water absorbability of the water absorbing roller can be quickly and effectively recovered without lowering the printing productivity as much as possible.

1 printing device 2 print head 3 printing medium supply device 10 printing medium conveying device 11 endless belt 12 cleaning device 12a injection nozzle 12b brush roller 12c injection nozzle 12d blade 14 roller moving device 14a, 14b rotating plate 14i moisture meter 15 water removal device 15a Water receiving tray 15b Pulley 16 Equipment frame M1 Motor (driving device)
M2 motor (drive unit)
P0 Belt divergence position P1 Belt water absorption position P2 Throttle position (belt divergence position)
P3 release position (belt divergence position)
R1, R2 Water absorbing rollers R1h, R2h Heater R3 Water absorbing roller R5 Squeezing roller S Print medium

Claims (9)

an endless belt that supports and conveys a print medium on its surface;
a cleaning device for cleaning the surface of the endless belt supporting the print medium with water;
a water absorbing roller that rolls in pressure contact with the surface and absorbs water adhering to the surface due to cleaning by the cleaning device;
a roller moving device that moves the water absorbing roller between a belt water absorbing position where the water absorbing roller is pressed against the surface and a belt separation position where the belt separates from the surface;
The roller moving device can be equipped with a plurality of the water absorbing rollers, and can replace one water absorbing roller at the belt water absorbing position with another water absorbing roller at the belt separation position ,
A print medium conveying device in which a heater is built in the water absorbing roller . an endless belt that supports and conveys a print medium on its surface;
a cleaning device for cleaning the surface of the endless belt supporting the print medium with water;
a water absorbing roller that rolls in pressure contact with the surface and absorbs water adhering to the surface due to cleaning by the cleaning device;
a roller moving device that moves the water absorbing roller between a belt water absorbing position where the water absorbing roller is pressed against the surface and a belt separation position where the belt separates from the surface;
a moisture meter for measuring the moisture content of the water absorbing roller at the belt water absorbing position;
The roller moving device can be equipped with a plurality of the water absorbing rollers, and can replace one water absorbing roller at the belt water absorbing position with another water absorbing roller at the belt separation position,
The roller moving device is a printing medium conveying device that moves the water absorbing roller related to the measurement result from the belt water absorption position to the belt separation position based on the measurement result of the moisture meter. an endless belt that supports and conveys a print medium on its surface;
a cleaning device for cleaning the surface of the endless belt supporting the print medium with water;
a water absorbing roller that rolls in pressure contact with the surface and absorbs water adhering to the surface due to cleaning by the cleaning device;
a roller moving device that moves the water absorbing roller between a belt water absorbing position where the water absorbing roller is pressed against the surface and a belt separation position where the belt separates from the surface;
a water removing device for removing water from the water absorbing roller at the belt divergence position ,
The roller moving device can be equipped with a plurality of the water absorbing rollers, and can replace one water absorbing roller at the belt water absorbing position with another water absorbing roller at the belt separation position. Conveyor. 4. The print medium conveying device according to claim 3 , wherein the water removing device includes a squeeze roller that presses against the water absorbing roller at the belt separation position, and a driving device that rotates the water absorbing roller and the squeeze roller while the water absorbing roller and the squeeze roller are in pressure contact with each other. . 5. The print medium conveying device according to claim 4, wherein the roller moving device can arrange the water absorbing roller at a position separated from the endless belt and the squeeze roller. A control device for controlling the driving device,
The drive device is independent of the drive system of the endless belt,
6. The print medium conveying device according to claim 4, wherein the control device variably controls the driving rotation speed. 7. The printing medium conveying device according to claim 4, 5, or 6, wherein the roller moving device moves the water absorbing roller between the belt water absorbing position and the squeeze position where the squeeze roller is in pressure contact with the same driving device. . 8. The print medium conveying device according to any one of claims 1 to 7 , wherein the roller moving device can be equipped with three or more water absorbing rollers. A print medium transport device according to any one of claims 1 to 8 ;
a print medium supply device that supplies a print medium to the surface of the endless belt in a section between the belt water absorption position and the cleaning device along the running direction of the endless belt;
a print head that prints on a print medium supported on the surface of the endless belt in the section.

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