JP6922274B2 - Paper humidifier and image forming system - Google Patents

Description

The present invention relates to a paper humidifier and an image forming system.

Conventionally, a paper processing apparatus having a plurality of paper transport paths inside, which is compatible with various paper processing functions for image-formed paper, has become widespread. In the paper processing device, from the viewpoint of preventing the size of the device from becoming large and reducing costs, a humidifying section for applying water to the paper to humidify the paper is provided at the inlet of the device before the paper transport path is branched into a plurality of branches. It is being considered. The humidifying portion has, for example, a humidifying roller pair capable of holding water on the outer peripheral surface, and is configured to apply water to the paper when the paper is sandwiched and conveyed by the humidifying roller pair.

In such a paper processing apparatus, since the humidifying paper and the non-humidifying paper pass through the same path, it is necessary to dry the humidifying roller pair when the non-humidifying paper passes after the humidifying paper. For example, Patent Document 1 discloses a technique for controlling drying of a humidifying roller pair at the end of job execution.

Japanese Unexamined Patent Publication No. 2011-107291

In recent years, based on the desire to increase the amount of humidification on paper, the development of a device provided with a humidifying portion capable of increasing the water content of a pair of humidifying rollers has been progressing.
However, as the water content of the humidifying roller pair increases, the time required to dry the humidifying roller pair also increases. Therefore, even if the control of Patent Document 1 is executed, the non-humidified paper is accepted after the paper is humidified. It took a long time, and productivity may decrease.
In particular, in the case of the configuration in which the humidifying portion is provided at the inlet portion of the apparatus as described above, it is desirable to dry the humidifying roller pair more quickly because the paper reaches the humidifying portion in a short time after the image is formed.

The present invention has been made in view of the above problems, and the time from humidifying the paper to the acceptance of the non-humidified paper is suppressed to a short time, and the decrease in productivity is suppressed. It is an object of the present invention to provide a paper humidifier and an image forming system capable of performing the same.

In order to solve the above problems, according to the present invention, in a paper humidifier,
A pair of humidifying rollers that abut each other to form a nip portion and apply water held on the surface to the paper to humidify the paper when the paper passing through the nip portion is sandwiched and conveyed.
A water supply roller that supplies water to each of the humidifying rollers,
A drive unit that brings the humidifying roller and the water supply roller into contact with each other or separated from each other.
When the humidifying roller shifts from a state in which the paper is humidified to a state in which the paper is not humidified, it is said that the front edge of the last paper to be humidified reaches a predetermined position upstream of the nip portion. A control unit that controls the drive unit to separate the humidifying roller and the water supply roller before the rear end of the last paper reaches the nip portion.
With
The control unit is characterized in that the separation timing between the humidifying roller and the water supply roller is adjusted according to the amount of water in the humidifying roller .

Further, according to the present invention, in an image forming system,
An image forming device that forms an image on paper,
The paper humidifier connected to the image forming apparatus and humidifying the paper on which the image is formed by the image forming apparatus, and the paper humidifying apparatus.
It is characterized by being equipped with.

According to the present invention, it is possible to reduce the time from humidifying the paper to accepting the non-humidified paper in a short time, and to suppress a decrease in productivity.

It is a figure which shows the schematic structure of the image formation system. It is a block diagram which shows the main functional composition of an image forming apparatus and a paper humidifying apparatus. It is a schematic diagram which shows the structure of a humidifying part. It is a flowchart which shows the operation of a humidifying part. It is a figure for demonstrating the operation of a humidifying part. It is a figure for demonstrating the operation of a humidifying part.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the scope of the invention is not limited to the illustrated examples.

First, the configuration of the paper humidifier and the image forming system in the present embodiment will be described.

FIG. 1 is a diagram showing a schematic configuration of an image forming system 1.
As shown in FIG. 1, the image forming system 1 includes an image forming device 3, a paper humidifying device 5, and a paper processing device 7.

The image forming apparatus 3 is an apparatus for forming an image on paper by an electrophotographic method. The image forming apparatus 3 conveys the paper on which the image is formed to the paper humidifying apparatus 5.
The paper humidifying device 5 is a device that performs a humidifying treatment of applying water to the paper conveyed from the image forming device 3. The paper humidifying device 5 conveys the humidified paper to the paper processing device 7. The paper humidifying device 5 can also convey the paper to the paper processing device 7 without performing the humidifying treatment.
The paper processing device 7 is a device that performs a predetermined paper processing on the paper conveyed from the paper humidifying device 5 and discharges the paper. Examples of the paper processing include decal processing, stapling processing, punching hole processing, folding processing, bookbinding processing, and the like.
The image forming device 3, the paper humidifying device 5, and the paper processing device 7 are configured to be detachable from adjacent devices.

FIG. 2 is a block diagram showing the main functional configurations of the image forming apparatus 3 and the paper humidifying apparatus 5.

The image forming apparatus 3 includes a control unit 30 having a CPU (Central Processing Unit) 301, a RAM (Random Access Memory) 302, and a ROM (Read Only Memory) 303, a storage unit 31, an operation unit 32, and a display unit 33. The external communication unit 34, the interface 35, the scanner 36, the image processing unit 37, the image forming unit 38, and the conveying unit 39 are provided.
The control unit 30 is connected to the storage unit 31, the operation unit 32, the display unit 33, the external communication unit 34, the interface 35, the scanner 36, the image processing unit 37, the image forming unit 38, and the conveying unit 39 via the bus 3b. ing.

The CPU 301 reads and executes a control program stored in the ROM 303 or the storage unit 31 to perform various arithmetic processes.

The RAM 302 provides the CPU 301 with a working memory space and stores temporary data.

The ROM 303 stores various control programs, setting data, and the like executed by the CPU 301. Instead of the ROM 303, a rewritable non-volatile memory such as an EEPROM (Electrically Erasable Programmable Read Only Memory) or a flash memory may be used.

The control unit 30 including the CPU 301, the RAM 302, and the ROM 303 collectively controls each unit of the image forming apparatus 3 according to the above-mentioned various control programs. For example, the control unit 30 causes the image processing unit 37 to perform predetermined image processing on the image data and stores the image data in the storage unit 31. Further, the control unit 30 conveys the paper to the conveying unit 39, and causes the image forming unit 38 to form an image on the paper based on the image data stored in the storage unit 31.

The storage unit 31 is composed of a DRAM (Dynamic Random Access Memory) or the like, and stores image data acquired by the scanner 36, image data input from the outside via the external communication unit 34, and the like. Note that these image data and the like may be stored in the RAM 302.

The operation unit 32 includes input devices such as a touch panel arranged so as to be superimposed on the operation keys and the screen of the display unit 33, and converts input operations for these input devices into operation signals and outputs them to the control unit 30.

The display unit 33 includes a display device such as an LCD (Liquid crystal display), and displays an operation screen or the like showing the state of the image forming system 1 or the content of an input operation on the touch panel.

The external communication unit 34 communicates with a computer or another image forming apparatus on the network in accordance with the control signal from the control unit 30 to transmit and receive image data and the like.

The interface 35 is a means for transmitting and receiving data to and from the paper humidifying device 5, and is composed of, for example, any of various serial interfaces.

The scanner 36 reads the image formed on the paper, generates image data including monochromatic image data for each color component of R (red), G (green), and B (blue), and stores the image data in the storage unit 31. ..

The image processing unit 37 includes a rasterization processing unit, a color conversion unit, a gradation correction unit, and a halftone processing unit. The image data stored in the storage unit 31 is subjected to various image processing and stored in the storage unit 31. ..

The rasterization processing unit converts vector-format image data described in a predetermined page description language (PDL) input from a computer or the like on the network into raster-format image data such as a bitmap. The image data converted and generated by the rasterization processing unit includes monochromatic image data for each color component of C (cyan), M (magenta), Y (yellow), and K (black).
The color conversion unit performs color conversion processing on the image data of each color of R, G, and B output from the scanner 36 with reference to a predetermined lookup table, and monochromatic image data of each color of C, M, Y, and K. Generate image data including. In addition, the color conversion unit performs a predetermined color correction process on the image data.
The gradation correction unit sets the gradation value of the image data by referring to a look-up table in which the correction value corresponding to each gradation value is defined so that the gradation characteristic of the image related to the image data becomes a predetermined characteristic. to correct.
The halftone processing unit performs halftone processing such as screen processing using a dither matrix and error diffusion processing on the image data.
The rasterization processing unit, the color conversion unit, the gradation correction unit, and the halftone processing unit included in the image processing unit 37 may be partially or wholly realized by the control unit 30, or the image forming apparatus 3 may be used. The configuration may be realized by another image processing device provided externally.

The image forming unit 38 forms an image on paper based on the image data stored in the storage unit 31. The image forming unit 38 includes four sets of exposure units 381, photoconductors 382, and developing units 383 corresponding to the color components of C, M, Y, and K, respectively. Further, the image forming unit 38 includes a transfer body 384, a secondary transfer roller 385, and a fixing unit 386.

The exposure unit 381 includes an LD (Laser Diode) as a light emitting element. The exposure unit 381 drives the LD based on the image data, irradiates the charged photoconductor 382 with a laser beam, and exposes the photoconductor 382 to form an electrostatic latent image on the photoconductor 382. The developing unit 383 supplies toner (coloring material) of a predetermined color (any of C, M, Y, and K) on the exposed photoconductor 382 by a developing roller charged on the exposed photoconductor 382. The formed electrostatic latent image is developed.
An image (monochromatic image) formed of the toners of C, M, Y, and K on each of the four photoconductors 382 corresponding to C, M, Y, and K is formed from each photoconductor 382 onto the transfer body 384. They are sequentially stacked and transferred. As a result, a color image having C, M, Y, and K as color components is formed on the transfer body 384.

The transfer body 384 is an endless belt wound around a plurality of transfer body transfer rollers, and rotates according to the rotation of each transfer body transfer roller.

The secondary transfer roller 385 transfers the color image on the transfer body 384 onto the paper fed from the paper feed tray 3a. Specifically, when a predetermined transfer voltage is applied to the secondary transfer roller 385 that sandwiches the paper and the transfer body 384, the toner forming the color image on the transfer body 384 is attracted to the paper side and becomes the paper. Transcribed.

The fixing unit 386 heats and pressurizes the paper on which the toner is transferred to perform a fixing process for fixing the toner on the paper. The fixing portion 386 includes a pair of rollers including a heating roller and a pressure roller for holding the paper. The heating roller is heated to a predetermined target temperature (for example, a temperature in the range of 180 ° C. or higher and 200 ° C. or lower) by a heater as a heating source. The pressure roller is urged toward the heating roller by an elastic member (not shown). The paper on which the image formed by the toner is transferred by the secondary transfer roller 385 passes through the nip portion between the heating roller and the pressure roller, so that the image formed by the toner is fixed on the paper.

The transport unit 39 includes a plurality of paper transport rollers for transporting the paper by rotating while sandwiching the paper, and transports the paper along a predetermined transport path. The transport unit 39 includes a resist roller 391 arranged on the upstream side of the secondary transfer roller 385 in the transport direction. The resist roller 391 temporarily stops the feeding of the fed paper, and adjusts the timing of feeding the paper to the secondary transfer roller 385. Further, the transport unit 39 includes a reversing mechanism 392 that reverses the front and back sides of the paper that has been fixed by the fixing unit 386 and transports the paper to the secondary transfer roller 385. In the image forming apparatus 3, the inversion mechanism 392 reverses the front and back of the paper when forming an image on both sides of the paper, and when the image is formed on only one side of the paper, the inversion mechanism 392 reverses the front and back of the paper. The paper is conveyed to the paper humidifier 5 without being inverted.

The paper humidifying device 5 includes a control unit 50 having a CPU 501, a RAM 502, and a ROM 503, an interface 51, a transport unit 52, a humidifying unit 53, and a paper processing unit 54.
The control unit 50 is connected to the interface 51, the transport unit 52, the humidification unit 53, and the paper processing unit 54 via the bus 5b.

The CPU 501 reads and executes a control program stored in the ROM 503, and performs various arithmetic processes.

The RAM 502 provides the CPU 501 with a working memory space and stores temporary data. This temporary data includes, for example, various setting information related to the humidification process.

The ROM 503 stores various control programs, setting data, and the like executed by the CPU 501. A rewritable non-volatile memory such as an EEPROM or a flash memory may be used instead of the ROM 503.

The control unit 50 including the CPU 501, the RAM 502, and the ROM 503 collectively controls each part of the paper humidifying device 5 according to the above-mentioned various control programs. For example, the control unit 50 causes the humidifying unit 53 to humidify the paper under the conditions indicated by the setting information stored in the RAM 502.

The interface 51 is a means for transmitting and receiving data to and from the image forming apparatus 3 as a communication unit, and is composed of, for example, any of various serial interfaces.

The transport unit 52 includes a guide member that guides the paper, a paper transport roller that transports the paper by rotating while sandwiching the paper, and the like, and transports the paper along the transport path 52a.

The humidifying unit 53 is a mechanism for performing a humidifying treatment in which water is applied to the paper to humidify the paper.
For example, by performing a humidifying treatment on the paper charged by the application of the transfer voltage or static electricity generated during transportation by the humidifying unit 53, it is possible to prevent the occurrence of phenomena such as floating and sticking of the paper.
The humidifying portion 53 of the present embodiment includes a pair of humidifying rollers arranged so as to be arranged in the vertical direction, and has a configuration in which water is applied to the paper when the paper to be conveyed in the horizontal direction is sandwiched and conveyed. The details of the humidifying section 53 will be described later.

The paper processing unit 54 is a mechanism for performing another paper processing on the paper that has passed through the humidifying unit 53. In the present embodiment, the paper processing unit 54 handles the paper that has been curled by transportation, fixing and heating, or the like. The decaler unit 541 to be corrected, the paper reversing unit 542 that appropriately reverses the front and back of the paper when ejected from the paper humidifying device 5, and the purging unit that stores the paper ejected from the paper humidifying device when a malfunction occurs. It is equipped with 543.

Next, the detailed configuration of the humidifying section 53 will be described.
FIG. 3 is a schematic view showing the configuration of the humidifying portion 53.

The humidifying section 53 includes an upper humidifying roller 531a, a lower humidifying roller 531b, an upper water supply roller 532a, a lower water supply roller 532b, a first pumping roller 533, a second pumping roller 534, an upper water storage section 535, a lower water storage section 536, and an upstream. It has a side sensor PS1 and a downstream sensor PS2, and is configured to humidify the conveyed paper from above and below the paper surface.
A guide member (not shown) is provided before and after the humidifying rollers 531a and 531b to vertically sandwich the transport path 52a, and the paper is guided by the guide member to reach the nip portion of the humidifying rollers 531a and 531b.

The humidifying rollers 531a and 531b, the water supply rollers 532a and 532b, the first pumping roller 533, and the second pumping roller 534 are all cylindrical members, and each has a rotation axis set parallel to the horizontal direction. Rotate to the center.
Further, all of these rollers have a structure capable of supporting water on the peripheral surface. Examples of the material of the outer peripheral surface capable of supporting water include a hydrophilic resin such as polypropylene.

The humidifying rollers 531a and 531b are arranged so as to be in contact with each other to form a nip portion.
The humidifying rollers 531a and 531b are provided with humidifying roller driving units 531a and 531b1 (see FIG. 6), respectively, and the humidifying rollers 531a and 531b can be moved in a direction of contacting or separating from each other by driving the driving units.

The upper water supply roller 532a comes into contact with the upper humidifying roller 531a and supplies water carried on the surface to the outer peripheral surface of the upper humidifying roller 531a. The lower water supply roller 532b abuts on the lower humidifying roller 531b and supplies the water carried on the surface to the outer peripheral surface of the lower humidifying roller 531b.
The water supply rollers 532a and 532b are provided with water supply roller drive units 532a and 532b1 (see FIG. 5), respectively. It can move in the direction of contacting or separating from the roller 531b.

The first pumping roller 533 and the second pumping roller 534 play a role of pumping the water stored in the upper water storage unit 535 and supplying it to the upper water supply roller 532a.
The first pumping roller 533 is arranged so as to be in contact with the upper water supply roller 532a, and the second pumping roller 534 is in contact with the first pumping roller 533 and in contact with the water stored in the upper water storage unit 535. Arranged like this.
In the present embodiment, the pumping roller is arranged only in the configuration on the upper side of the humidifying section 53, and the upper water supply roller 532a does not come into direct contact with the water stored in the upper water storage section 535, but is the first pumping roller. Water is supplied via 533 and a second pumping roller 534.
On the other hand, the lower water supply roller 532b is arranged so as to be in contact with the water stored in the lower water storage unit 536, and is configured to receive water directly from the lower water storage unit 536.
However, the present invention is not limited to this embodiment, and a pumping roller that comes into contact with the lower water supply roller 532b may be provided.

The upper water storage unit 535 and the lower water storage unit 536 play a role of storing water for humidifying the paper.
In the present embodiment, the upper water storage unit 535 is arranged so as to supply water to the upper water supply roller 532a via the first pumping roller 533 and the second pumping roller 534.
Further, the lower water storage unit 536 is arranged so as to supply water to the lower water supply roller 532b.
Further, the water stored in the upper water storage unit 535 and the lower water storage unit 536 may contain an additive such as a surfactant within a range that does not hinder the image. When the water contains an additive, the amount of water retained on the surfaces of the humidifying rollers 531a and 531b increases.

The upstream sensor PS1 is provided on the upstream side of the humidifying rollers 531a and 531b with respect to the transport path 52a, and the downstream sensor PS2 is provided on the downstream side of the humidifying rollers 531a and 531b with respect to the transport path 52a. There is.
The upstream sensor PS1 and the downstream sensor PS2 are, for example, optical sensors and detect paper passing through the transport path 52a.

Although not shown, the configuration may include a drain roller that regulates the amount of water held on the surfaces of the upper water supply roller 532a and the lower water supply roller 532b and absorbs water.

The upper humidifying roller 531a and the lower humidifying roller 531b are rotated by the rotation drive unit M to form a nip and convey the paper, so that they rotate in opposite directions (with direction).
The upper water supply roller 532a rotates in the with direction in conjunction with the rotation of the upper humidifying roller 531a, and the lower water supply roller 532b rotates in the with direction in conjunction with the rotation of the lower humidifying roller 531b. Further, the first pumping roller 533 rotates in the with direction in conjunction with the rotation of the upper water supply roller 532a, and the second pumping roller 534 interlocks with the rotation of the first pumping roller 533 in the with direction. Rotate to.

In the present embodiment, the water supply rollers 532a, 532b, the first pumping roller 533, and the second pumping roller 534 are rotating in conjunction with (following) the rotation direction of the humidifying rollers 531a and 531b. As an embodiment of the above, a mode in which a drive unit is provided on each humidifying roller, each water supply roller, and each pumping roller and is rotated is also conceivable.

Next, the operation of the humidifying unit 53 performed in the paper humidifying device 5 of the image forming system 1 having the above configuration will be described.

The paper humidifying device 5 of the present embodiment executes control that enables quick switching between a job that humidifies the paper and a job that does not humidify the paper in succession. be.
Specifically, such control quickly dries the wet humidifying rollers 531a and 531b by executing a job that humidifies the paper, and shortens the waiting time until the start of a subsequent job that does not humidify. It makes it possible to do so.

FIG. 4 is a flowchart showing the operation of the humidifying unit 53 when the job type is switched as described above. 5 and 6 are diagrams for explaining the operation of the humidifying unit 53.
The operation of the humidifying unit 53 is executed under the control of the control unit 50 of the paper humidifying device 5.
Further, such an operation is performed during the execution of the job of humidifying the paper. That is, the humidifying rollers 531a and 531b rotate at a predetermined speed (referred to as "normal speed") in a state where the humidifying rollers 531a and 531b are in contact with each other to form a nip portion, and moisturize the paper P while sandwiching and transporting the paper P. ing.

First, the control unit 50 determines whether or not the tip of the final paper M of the job being executed has reached PS1 (predetermined position) (step S101), and if it has not reached it (step S101: NO), it takes. The process of step S101 is repeated.

On the other hand, when the tip of the final paper M of the job being executed reaches PS1 (step S101: YES), the control unit 50 determines whether or not there is a reservation for the next job (step S102), and the next job If there is no reservation (step S102: NO), the process proceeds to step S114 described later.

On the other hand, when there is a reservation for the next job (step S102: YES), the control unit 50 determines whether or not the next job is humidified (step S103), and when the next job has humidification (step S103: NO). , The process proceeds to step S112 described later.

On the other hand, when there is no humidification in the next job (step S103: YES), the control unit 50 separates the water supply rollers 532a and 532b from the humidifying rollers 531a and 531b (step S104).
Specifically, as shown in FIG. 5, the control unit 50 controls the water supply roller drive units 532a1, 532b1 to move the upper water supply roller 532a upward and the lower water supply roller 532b downward, and each water supply roller. The 532a and 532b are separated from the humidifying rollers 531a and 531b.
Even after the water supply rollers 532a and 532b are separated from each other, the humidifying rollers 531a and 531b are maintained in contact with each other.
As a result, the water supply from the water supply rollers 532a and 532b to the humidifying rollers 531a and 531b is stopped, but the humidification treatment for the final paper M is continued by the moisture retained on the surfaces of the humidifying rollers 531a and 531b.

Next, the control unit 50 determines whether or not the rear end of the final paper M has passed PS2 (step S105), and if it has not passed (step S105: NO), repeats the process of step S105.

On the other hand, when the final paper M has passed through PS2 (step S105: YES), the control unit 50 separates the humidifying rollers 531a and 531b from each other (step S106).
Specifically, as shown in FIG. 6, the control unit 50 controls the humidifying roller driving units 531a1 and 531b1 to move the upper humidifying roller 531a upward and the lower humidifying roller 531b downward, and the humidifying roller 531a. , 531b are separated from each other.
As a result, the humidifying rollers 531a and 531b are easily naturally dried.

Next, the control unit 50 controls the rotation drive unit M, and changes the rotation speed of the humidifying rollers 531a and 531b to a predetermined speed (referred to as “first speed”) higher than the normal speed (step S107).
Specifically, the control unit 50 increases the rotation speed of the humidifying rollers 531a and 531b to the first speed by increasing the amount of current flowing through the rotation drive unit M to a predetermined value.
As a result, the humidifying rollers 531a and 531b rotate at a high speed in the state shown in FIG. 6, and centrifugal force is applied to make the humidifying rollers 531a and 531b easier to dry.

Next, the control unit 50 determines whether or not the predetermined time has elapsed (step S108), and if the predetermined time has not elapsed (step S108: NO), repeats the process of step S108.
Here, the control unit 50 adjusts the predetermined time according to the amount of water held by the humidifying rollers 531a and 531b.
For example, when the water contains an additive, the amount of water held by the humidifying rollers 531a and 531b increases. Therefore, when the water held by the humidifying rollers 531a and 531b contains the additive, the control unit 50 determines the above. The time is adjusted to be longer than the set value, and when the water held by the humidifying rollers 531a and 531b does not contain additives, the predetermined time is set as the set value.

On the other hand, when a predetermined time has elapsed (step S108: YES), the control unit 50 controls the rotation drive unit M and changes the rotation speed of the humidifying rollers 531a and 531b from the first speed to the normal speed (step S109). ..

Next, the control unit 50 brings the humidifying rollers 531a and 531b into contact with each other (step S110), starts the next job without humidification (step S111), and ends this process.
As a result, the humidifying rollers 531a and 531b come into contact with each other in a dry state, and the next job without humidification is started.

Further, in step S103, when the next job is humidified (step S103: NO), the control unit 50 determines whether or not the executing job (job 1) has been completed (step S112), and ends. If not (step S112: NO), the process of step S112 is repeated.

On the other hand, when the running job is completed (step S112: YES), the control unit 50 starts the next job (job 2) with humidification (step S113), and ends this process.

Further, in step S102, when there is no reservation for the next job (step S102: NO), the control unit 50 separates the water supply rollers 532a and 532b from the humidifying rollers 531a and 531b (step S114). The process of step S114 is the same as that of step S104.

Next, the control unit 50 determines whether or not the rear end of the final paper M has passed through PS2 (step S115), and if not (step S115: NO), repeats the process of step S115.

On the other hand, when the rear end of the final paper M has passed through PS2 (step S115: YES), the control unit 50 separates the humidifying rollers 531a and 531b from each other (step S116). The process of step S116 is the same as that of step S106.

Next, the control unit 50 changes the rotation speed of the humidifying rollers 531a and 531b from the normal speed to the first speed (step S117). The process of step S117 is the same as that of step S107.

Next, the control unit 50 determines whether or not the predetermined time has elapsed (step S118), and if the predetermined time has not elapsed (step S118: NO), repeats the process of step S118. The process of step S118 is the same as that of step S108.

On the other hand, when a predetermined time has elapsed (step S118: YES), the control unit 50 controls the rotation drive unit M and stops the rotation of the humidifying rollers 531a and 531b rotating at the first speed (step S119). , End this process.
As a result, the humidifying rollers 531a and 531b stop rotating in a dry state.

As described above, according to the present embodiment, the nip portions are formed in contact with each other, and when the paper passing through the nip portion is sandwiched and conveyed, the water retained on the surface is applied to the paper to humidify the paper. A pair of humidifying rollers 531a, 531b, water supply rollers 532a, 532b that supply water to each of the humidifying rollers 531a, 531b, and water supply roller drive units 532a1, that bring the humidifying rollers 531a, 531b and the water supply rollers 532a, 532b into contact with each other. When the 532b1 and the humidifying rollers 531a and 531b shift from the state where the paper is humidified to the state where the paper is not humidified, the front edge of the last paper to be humidified reaches a predetermined position upstream of the nip portion. Then, before the rear end of the last paper reaches the nip portion, the control unit 50 that controls the water supply roller drive units 532a and 532b1 to separate the humidifying rollers 531a and 531b from the water supply rollers 532a and 532b. To be equipped with.
Therefore, when shifting from the state in which the paper is humidified to the state in which the paper is not humidified, after the front end of the last paper to be humidified reaches a predetermined position upstream of the nip portion, the last In order to separate the humidifying rollers 531a and 531b from the water supply rollers 532a and 532b before the rear end of the paper reaches the nip, the humidifying roller does not wait for the rear end of the last paper to be humidified to pass through the nip. Since the water supply to the 531a and 531b is stopped, an excessive supply of water is prevented, and the humidifying rollers 531a and 531b are easily dried.
Therefore, after humidifying the paper, the time until the paper without humidification can be accepted can be suppressed in a short time, and the decrease in productivity can be suppressed.
Further, since the humidifying rollers 531a and 531b are easily dried without being equipped with a fan for drying, the cost can be suppressed as compared with the configuration in which the fan is mounted.

Further, according to the present embodiment, the humidifying roller driving units 531a1 and 531b1 are provided to bring the humidifying rollers 531a and 531b into contact with each other or separated from each other, and the control unit 50 has the rear end of the last paper to be humidified passing through the nip portion. After that, the humidifying roller driving units 531a1 and 531b1 are controlled to separate the humidifying rollers 531a and 531b from each other.
Therefore, the operation of drying the humidifying rollers 531a and 531b can be started after waiting for the final humidification of the paper.

Further, according to the present embodiment, the control unit 50 executes a high-speed rotation operation in which the humidifying rollers 531a and 531b in a separated state are rotated at a speed higher than the normal speed when the paper is sandwiched and conveyed for a predetermined time. ..
Therefore, centrifugal force is applied to the humidified rollers 531a and 531b in a separated state, and the humidifying rollers 531a and 531b can be dried more quickly, so that the productivity can be further improved.
Further, at this time, since the humidifying rollers 531a and 531b are separated from each other, there is no friction due to contact between the humidifying rollers 531a and 531b, and the load applied to the rotation drive unit M is small. Can be executed.

Further, according to the present embodiment, the control unit 50 adjusts the time for high-speed rotation according to the amount of water in the humidifying rollers 531a and 531b.
Therefore, the high-speed rotation operation is not unnecessarily executed, and the wasteful consumption of the current amount can be suppressed.

Further, according to the present embodiment, the control unit 50 adjusts the time for high-speed rotation depending on whether or not the water held by the humidifying rollers 531a and 531b contains additives.
Therefore, when it is determined that the amount of water is large due to the inclusion of additives in the water, the time for high-speed rotation can be lengthened.

Further, according to the present embodiment, the control unit 50 includes an interface 51 that communicates with the image forming apparatus 3 that forms an image on the paper, and the control unit 50 does not humidify the paper for the time required for the high-speed rotation operation. The command to stop the transfer is notified to the image forming apparatus 3 via the interface 51.
Therefore, it is possible to wait for the humidifying rollers 531a and 531b to dry before starting the transfer of the paper without humidification.

In the above embodiment, the time of switching between the job of humidifying the paper and the time of switching between the jobs without humidification have been described as an example, but the next paper is humidified or not for each paper, not for each job. It may be configured to determine whether or not it is present.

Further, according to the above embodiment, the humidifying rollers 531a and 531b and the water supply rollers 532a and 532b are separated from each other at the timing (at the time of arrival) when the front end of the paper reaches PS1, but the rear end of the paper is Depending on the timing of reaching PS1 (at the time of arrival), the humidifying rollers 531a and 531b and the water supply rollers 532a and 532b may be separated from each other.

Further, the separation timing between the humidifying rollers 531a and 531b and the water supply rollers 532a and 532b may be adjusted according to the amount of water in the humidifying rollers 531a and 531b.
For example, when the water contains an additive, the water content of the humidifying rollers 531a and 531b increases. Therefore, when the water held by the humidifying rollers 531a and 531b contains the additive, the control unit 50 sets the separation timing. The timing at which the tip of the paper reaches PS1 is set, and when no additive is contained, the separation timing is set after a predetermined time has elapsed after the tip of the paper reaches PS1.
By doing so, the water supply from the water supply rollers 532a and 532b can be stopped according to the wetness of the humidifying rollers 531a and 531b, so that the humidifying rollers 531a and 531b can be dried more easily.

Further, in the above embodiment, the configuration in which both the humidifying rollers 531a and 531b operate when the humidifying rollers 531a and 531b are separated from each other has been described as an example, but even if only one of the humidifying rollers 531a and 531b operates. good. That is, the humidifying roller driving unit may be provided only on one of the humidifying rollers 531a and 531b.

Further, in the above embodiment, as a high-speed rotation operation of the humidifying rollers 531a and 531b, control is performed to increase the rotation speed of the humidifying rollers 531a and 531b to the first speed by increasing the amount of current to a predetermined value. However, at the user's discretion, if it is desired to prioritize productivity, the amount of current may be increased to the maximum value and a second high-speed rotation operation of rotating at a second speed higher than the first speed may be executed. ..
By doing so, since the centrifugal force is increased, the humidifying rollers 531a and 531b can be dried in a shorter time, and the productivity can be further improved.

Further, in the above embodiment, the configuration in which the humidifying section 53 is provided in the transport path in which the paper is transported in the horizontal direction is illustrated and described, but the humidifying section 53 is provided in the transport path in which the paper is transported in the vertical direction. It can also be configured.

1 Image forming system 3 Image forming device 30 Control unit 31 Storage unit 32 Operation unit 33 Display unit 34 External communication unit 35 Interface 36 Scanner 37 Image processing unit 38 Image forming unit 39 Transport unit 3a Paper feed tray 3b Bus 5 Paper humidifying device 50 Control unit 51 interface (communication unit)
52 Conveying unit 53 Humidifying unit 531a Upper humidifying roller 531b Lower humidifying roller 531a1, 531b1 Humidifying roller drive unit (second drive unit)
M Rotational drive unit 532a Upper water supply roller 532b Lower water supply roller 532a1,532b1 Water supply roller drive unit (drive unit)
533 First pumping roller 534 Second pumping roller 535 Upper water storage part 536 Lower water storage part PS1 Upstream side sensor PS2 Downstream side sensor 5b Bus 54 Paper processing part 541 Decala part 542 Paper reversing part 543 Purge part 52a Transport path 7 Paper processing Device P paper

Claims (9)

A pair of humidifying rollers that abut each other to form a nip portion and apply water held on the surface to the paper to humidify the paper when the paper passing through the nip portion is sandwiched and conveyed.
A water supply roller that supplies water to each of the humidifying rollers,
A drive unit that brings the humidifying roller and the water supply roller into contact with each other or separated from each other.
When the humidifying roller shifts from a state in which the paper is humidified to a state in which the paper is not humidified, it is said that the front edge of the last paper to be humidified reaches a predetermined position upstream of the nip portion. A control unit that controls the drive unit to separate the humidifying roller and the water supply roller before the rear end of the last paper reaches the nip portion.
Bei to give a,
The control unit is a paper humidifying device characterized in that the separation timing between the humidifying roller and the water supply roller is adjusted according to the amount of water in the humidifying roller. The paper according to claim 1, wherein the control unit adjusts the separation timing between the humidifying roller and the water supply roller according to whether or not the water held by the humidifying roller contains an additive. Humidifier. A second drive unit for bringing the humidifying rollers into contact with each other or separating them from each other is provided.
1. The paper humidifier according to 2. A pair of humidifying rollers that abut each other to form a nip portion and apply water held on the surface to the paper to humidify the paper when the paper passing through the nip portion is sandwiched and conveyed.
A water supply roller that supplies water to each of the humidifying rollers,
A drive unit that brings the humidifying roller and the water supply roller into contact with each other or separated from each other.
From the state of pre-Symbol humidifying roller is performing humidified paper, when shifting to a state of not performing humidification to the sheet, and the front end of the last sheet to humidify reaches a predetermined position upstream of said nip portion, A control unit that controls the drive unit to separate the humidifying roller and the water supply roller before the rear end of the last paper reaches the nip portion.
A second drive unit that brings the humidifying rollers into contact with each other or separates them from each other .
With
After the rear end of the last paper to be humidified passes through the nip portion, the control unit controls the second drive unit to separate the humidifying rollers from each other and separate the humidifying rollers. A paper humidifying device characterized by executing a high-speed rotation operation of rotating at a first speed higher than a normal speed when holding and transporting paper for a predetermined time. The paper humidifying device according to claim 4, wherein the control unit adjusts the predetermined time according to the amount of water in the humidifying roller. The paper humidifying device according to claim 5, wherein the control unit adjusts the predetermined time according to whether or not the water held by the humidifying roller contains an additive. The claim is characterized in that the control unit can execute a second high-speed rotation operation in which the humidifying roller in a separated state is rotated at a second speed higher than the first speed for a second predetermined time. Item 4. The paper humidifying device according to any one of Items 4 to 6. It is equipped with a communication unit that communicates with an image forming device that forms an image on paper.
4. The control unit 4 to 7 notifies the image forming apparatus via the communication unit of a command to stop the transfer of paper that is not humidified for a time required for the high-speed rotation operation. The paper humidifier according to any one of the items. An image forming device that forms an image on paper,
The paper humidifier according to any one of claims 1 to 8, which is connected to the image forming apparatus and humidifies the paper on which the image is formed by the image forming apparatus.
An image forming system characterized by being equipped with.

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