JP6977441B2 - Paper humidifiers, image forming systems and programs - Google Patents

Description

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

Conventionally, in an electrophotographic image forming apparatus, as one of measures against problems such as paper deformation such as curling and waviness, or sticking between stacked papers, a humidified part that applies water to the paper is used as a countermeasure. The technique of humidifying is known.
The humidifying section has, for example, a humidifying roller pair and a water supply roller that supplies water to the humidifying roller pair, and is configured to apply water to the paper when the paper is sandwiched and conveyed by the humidifying roller pair (for example). , Patent Document 1).

Japanese Unexamined Patent Publication No. 2014-202900

However, in such a humidifying section, since the humidifying roller pair immediately after humidifying the paper contains water, a problem may occur if the subsequent job is performed as it is.
Specifically, for example, after a job in which the humidification amount is set to be larger than the standard value, a job in which the humidification amount is set to be less than the standard value is set as a subsequent job (for example, a job for humidifying thin paper or a job not humidifying). In the subsequent job, there is a possibility that the corners of the paper may be folded or the paper may be wrapped.

The present invention has been made in view of the above problems, and is to prevent the occurrence of defects when the amount of humidification is reduced.

In order to solve the above problems, the paper humidifier of the present invention is used.
A pair of humidifying rollers that moisturize the paper when it is sandwiched and transported,
A water supply roller that contacts the humidifying roller to supply water,
A draining member provided so as to be in contact with at least one of the humidifying roller and the water supply roller.
When the water content of the humidifying roller is switched from the first state to the second state, which is less than the first state, the draining member is placed between the papers with respect to at least one of the humidifying roller and the water supply roller. And the control unit that performs the draining operation to make contact
Equipped with
The control unit
From the state where the humidifying roller and the water supply roller are in contact with each other and the draining member is separated from the humidifying roller and the water supply roller, the draining member is placed on at least one of the humidifying roller and the water supply roller as the draining operation. the contacted holds a predetermined time, then it said Rukoto is separated the dampening roller from the humidifying roller.

Further, the image forming system of the present invention is
An image forming device that forms an image on paper,
The paper humidifier, which moisturizes the paper on which the image is formed by the image forming apparatus,
It is characterized by being equipped with.

Further, the program of the present invention is
A pair of humidifying rollers that moisturize the paper when it is sandwiched and transported,
A water supply roller that contacts the humidifying roller to supply water,
A computer of a paper humidifier provided with a draining member provided so as to be in contact with and detachable from at least one of the humidifying roller and the water supply roller.
When the water content of the humidifying roller is switched from the first state to the second state, which is less than the first state, the draining member is placed between the papers with respect to at least one of the humidifying roller and the water supply roller. to function as a control unit for draining operation of contacting Te,
The control unit
From the state where the humidifying roller and the water supply roller are in contact with each other and the draining member is separated from the humidifying roller and the water supply roller, the draining member is placed on at least one of the humidifying roller and the water supply roller as the draining operation. the contacted holds a predetermined time, then, it is because of a program is separated the dampening roller from the humidifying roller.

According to the present invention, it is possible to prevent the occurrence of defects when the amount of humidification is reduced.

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 flowchart which shows the operation of a humidifying part. It is a schematic diagram for demonstrating the first initial operation. It is a schematic diagram for demonstrating the 2nd initial operation. It is a figure which shows the draining member of another aspect.

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.

[Configuration of image formation system]
First, the configuration of 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 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, staple processing, punching hole processing, folding processing, bookbinding processing, and the like.
The image forming apparatus 3, the paper humidifying apparatus 5, and the paper processing apparatus 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.

<Image forming device>
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. , An external communication unit 34, an interface 35, a scanner 36, an image processing unit 37, an image forming unit 38, and a transport unit 39.
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 transport 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, and performs various arithmetic processes.

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

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

The control unit 30 including the CPU 301, RAM 302, and 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 on the network or another image forming apparatus according to a control signal from the control unit 30, and transmits / receives image data or the like.

The interface 35 is a means for transmitting and receiving data to and from the paper humidifying device 5, and is configured by, 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 of the C (cyan), M (magenta), Y (yellow), and K (black) color components.
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 look-up table, and monochromatic image data of each color of C, M, Y, and K. Generate image data including. Further, 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. It may be configured to 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 exposed units 381, a photoconductor 382, and a developing unit 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 (see FIG. 1).

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) onto the 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 transferred from each photoconductor 382 onto the transfer body 384. It is sequentially stacked and transferred. As a result, a color image containing 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 to 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 within 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 on 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 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 is provided with a reversing mechanism 392 that reverses the front and back 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, when the image is formed on both sides of the paper, the front and back sides of the paper are inverted by the inversion mechanism 392, and when the image is formed on only one side of the paper, the front and back sides of the paper are inverted by the inversion mechanism 392. The paper is conveyed to the paper humidifying device 5 without being inverted.

<Paper humidifier>
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 out 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 unit 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 configured by, 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 (see FIG. 3).

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 is configured to apply water to the paper when the paper to be conveyed in the horizontal direction is sandwiched and conveyed. The details of the humidifying unit 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, and in the present embodiment, the paper processing unit 54 handles the paper that has been curled by transportation, fixing and heating, or the like. Decala unit 541 for correction, paper reversing unit 542 that appropriately reverses the front and back of the paper when ejecting from the paper humidifying device 5, and a 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, an upper drainer roller (drainer member) 533a, a lower drainer roller (drainer member) 533b, and a first pumping roller 534. It has a second pumping roller 535, an upper water storage unit 536, a lower water storage unit 537, an upstream side sensor PS1 and a downstream side 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 draining rollers 533a and 533b, the first pumping roller 534 and the second pumping roller 535 are all cylindrical members and are parallel to each other in the horizontal direction. Rotates around the axis of rotation set to.
Further, all of these rollers have a structure capable of supporting water on the peripheral surface.

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 can also be separated from each other.
The peripheral surface of the humidifying rollers 531a and 531b is formed of a hydrophilic resin such as nitrile rubber (NBR).

The upper water supply roller 532a abuts on the upper humidifying roller 531a and supplies water carried on the surface to the outer peripheral surface of the upper humidifying roller 531a. The peripheral surface of the upper water supply roller 532a is formed of, for example, a resin such as polypropylene.
The lower water supply roller 532b abuts on the lower humidifying roller 531b and supplies water carried on the surface to the outer peripheral surface of the lower humidifying roller 531b. The peripheral surface of the lower water supply roller 532b is formed of, for example, a resin such as nitrile rubber (NBR).

In the present embodiment, the upper water supply roller 532a can be brought into contact with or separated from the upper humidifying roller 531a by the first drive unit 61.
Further, the lower humidifying roller 531b can also be brought into contact with or separated from the lower water supply roller 532b by the first drive unit 61.

The upper drain roller 533a is arranged at a position where it can come into contact with the upper water supply roller 532a, regulates the amount of water carried on the outer peripheral surface of the upper water supply roller 532a, and absorbs water.
The lower drain roller 533b is arranged at a position capable of contacting the lower water supply roller 532b, regulates the amount of water carried on the outer peripheral surface of the lower water supply roller 532b, and absorbs water.
The peripheral surfaces of the drain rollers 533a and 533b are formed by using a water-absorbent material such as polyurethane.

In the present embodiment, the upper drain roller 533a can be brought into contact with or separated from the upper water supply roller 532a by the second drive unit 62.
Further, the lower drain roller 533b can also be brought into contact with or separated from the lower water supply roller 532b by the second drive unit 62.

The first pumping roller 534 and the second pumping roller 535 are responsible for pumping up the water stored in the upper water storage unit 536 and supplying it to the upper water supply roller 532a.
The first pumping roller 534 is arranged so as to be in contact with the upper water supply roller 532a, and the second pumping roller 535 is in contact with the first pumping roller 534 and is in contact with the water stored in the upper water storage unit 536. 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 536, but is the first pumping roller. It is configured to receive water supply via 534 and a second pumping roller 535.
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 537, and is configured to receive water directly from the lower water storage unit 537.
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 536 and the lower water storage unit 537 play a role of storing water for humidifying the paper.
In the present embodiment, the upper water storage unit 536 is arranged so as to supply water to the upper water supply roller 532a via the first pumping roller 534 and the second pumping roller 535. Further, the lower water storage unit 537 is arranged so as to supply water to the lower water supply roller 532b.
The upper water storage section 536 and the lower water storage section 537 are also arranged below the drain rollers 533a and 533b in order to receive water spilling from the upper drain roller 533a and the lower drain roller 533b, respectively.
Further, the water stored in the upper water storage unit 536 and the lower water storage unit 537 may contain an additive such as a surfactant within a range that does not impair 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 be further provided with a drawing member for removing the water absorbed by the draining rollers 533a and 533b.

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 534 rotates in the with direction in conjunction with the rotation of the upper water supply roller 532a, and the second pumping roller 535 interlocks with the rotation of the first pumping roller 534 in the with direction. Rotate to.

In the present embodiment, the water supply rollers 532a, 532b, the first pumping roller 534, and the second pumping roller 535 rotate in conjunction with (following) the rotation direction of the humidifying rollers 531a and 531b, but other 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.

[Operation of the humidifying part performed in the paper humidifier]
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.

When the job is completed, the paper humidifying device 5 executes an initial operation (initial operation) for starting the next job, and starts accepting paper for the next job.
The initial operation in the present embodiment is that when the amount of humidification is smaller than that of the previous job (previous paper), the subsequent paper corner folds and paper wrapping that may occur due to the moisture remaining in the humidifying rollers 531a and 531b. It includes a draining operation to suppress the occurrence of problems such as.

Hereinafter, the operation of the humidifying unit 53 will be described.
4 and 5 are flowcharts showing the operation of the humidifying unit 53. Further, FIG. 6 is a schematic diagram for explaining the first initial operation, and FIG. 7 is a schematic diagram for explaining the second initial operation.
The humidifying unit 53 operates under the control of the control unit 50 of the paper humidifying device 5. Further, the following operations are performed between jobs (between papers), and are started when the preceding job is completed.
Further, when the preceding job is completed, as shown in FIGS. 6A and 7A, the water supply rollers 532a and 532b are in contact with the humidifying rollers 531a and 531b, and the water supply rollers 532a and 532b are in contact with each other. The drain rollers 533a and 533b are separated from each other.

First, the control unit 50 determines whether or not the humidification treatment has been performed in the previous job (previous paper) (step S1), and if the humidification treatment has not been performed (step S1: NO), the first step to be described later. The initial operation of 1 is executed (step S2), and then the process proceeds to step S6 described later.

On the other hand, when the humidification process has been performed (step S1: YES), the control unit 50 determines whether or not the humidification amount of the previous job (previous paper) is equal to or greater than the predetermined amount (step S3). If the amount is less than the fixed amount (step S3: NO), the process proceeds to step S2.

On the other hand, when the humidification amount of the previous job (previous paper) is equal to or more than the predetermined amount (step S3: YES), the control unit 50 has the humidification amount of the next job (next paper) equal to or less than the predetermined amount. It is determined whether or not the amount is larger than the predetermined amount (step S4: NO), and the process proceeds to step S2.

On the other hand, when the humidification amount of the next job (next paper) is not more than a predetermined amount (step S4: YES), the control unit 50 executes the second initial operation (step S5: NO), and then described later. Step S6.

Here, the first initial operation in step S2 is when it is determined that the amount of water remaining in the humidifying rollers 531a, 531b and the water supply rollers 532a, 532b is not large or large, and the humidification of the subsequent job. This is an initial operation to be executed when it is determined that the amount of water remaining in the humidifying rollers 531a and 531b and the water supply rollers 532a and 532b may be large because the amount is set to be large.
Specifically, the control unit 50 drives the first drive unit 61 from the state shown in FIG. 6A to humidify the water supply rollers 532a and 532b, as shown in FIG. 6B. The humidifying rollers 531a and 531b are rotated (idle) by switching to a state separated from the 531b.
As a result, as shown in FIG. 6C, the humidifying rollers 531a and 531b can be suitably dried.
The state of FIG. 6C is an initial state before accepting the subsequent paper.

Further, the second initial operation in step S5 is when it is determined that the amount of water remaining in the humidifying rollers 531a, 531b and the water supply rollers 532a, 532b is larger than the required amount in the subsequent job (first). 1), the initial operation executed to switch to the water content (second state) that does not become excessive in the subsequent job.

FIG. 5 is a flowchart showing the second initial operation.

First, the control unit 50 determines whether or not the water content of the humidifying rollers 531a and 531b is equal to or higher than a predetermined value based on the settings of the previous job (step S51), and if it is less than the predetermined value (step S51: NO). , The draining time is set to the default value (step S52), and the process proceeds to step S55 described later.

Then, when the water content of the humidifying rollers 531a and 531b is equal to or greater than a predetermined value (step S51: YES), the control unit 50 determines whether or not the humidifying amount of the next sheet is equal to or greater than the predetermined value (step S53). When the humidification amount of the paper is equal to or more than a predetermined value (step S53: YES), the process proceeds to step S52.

On the other hand, when the humidification amount of the next sheet is less than the predetermined value (step S53: NO), the control unit 50 sets the draining time longer than the default value (step S54).

Next, the control unit 50 performs a draining operation at the set draining time (step S55).
The draining operation is an operation of removing the water adhering to the water supply rollers 532a and 532b by rotating the draining rollers 533a and 533b in a state of being in contact with the water supply rollers 532a and 532b.
The draining time is the time for bringing the draining rollers 533a and 533b into contact with the water supply rollers 532a and 532b.
Specifically, the control unit 50 drives the second drive unit 62 from the state shown in FIG. 7 (a) to the water supply rollers 532a, 532b, and the drain roller 533a, as shown in FIG. 7 (b). The 533b is brought into contact with and rotated, and this state is maintained for the set draining time.
As a result, as shown in FIG. 7 (c), the water adhering to the water supply rollers 532a and 532b is quickly removed, and the humidifying rollers 531a and 531b can be suitably dried.
Further, as described above, the moisture content of the humidifying rollers 531a and 531b in the previous job (previous paper) is equal to or higher than the predetermined value, and the humidifying amount of the next job (next paper) is smaller than the predetermined value. In that case, that is, when it is determined that a large amount of water remains in the humidifying rollers 531a and 531b compared to the amount of humidification to the next paper, the drainage time is longer than the default value, which is more effective. It is a target.
Then, when the set draining time elapses, the control unit 50 drives the first drive unit 61 to separate the water supply rollers 532a and 532b from the humidifying rollers 531a and 531b, as shown in FIG. 7D. Switch to the let state. In this state, the humidifying rollers 531a and 531b may be rotated (idle).
The state of FIG. 7D is an initial state before accepting the subsequent paper.

Returning to FIG. 4, the control unit 50 then determines whether or not the paper for the next job satisfies a preset predetermined condition in which it is determined that the tip of the paper is likely to be wrapped (step S6). ..
The predetermined conditions include, for example, the type of paper, the basis weight, the size, and the like.
For example, the control unit 50 determines that a predetermined condition is satisfied when the plain paper has a basis weight of 49 g / m ² or less, or when the coated ^{paper has a basis weight of 135 g / m 2 or less.} ..

Then, when it is determined that the paper for the next job satisfies the predetermined condition (step S6: YES), the control unit 50 executes the separation operation at the time of receiving the paper (step S7).
Specifically, when the next paper satisfies a predetermined condition in which it is determined that the tip of the paper is likely to be wrapped, the control unit 50 receives the paper with the humidifying rollers 531a and 531b separated from each other, and the tip of the paper receives the paper. After passing through the positions corresponding to the nip portions of the humidifying rollers 531a and 531b, the control for bringing the humidifying rollers 531a and 531b into contact again is executed.
As a result, even if the humidifying rollers 531a and 531b are dried by the first and second initial operations, there is a concern that the tip of the paper may be wrapped when a small amount of water remains on the humidifying rollers 531a and 531b. However, it is possible to prevent this.

Next, the control unit 50 determines whether or not the predetermined number of sheets has elapsed (step S8), and if the predetermined number of sheets has not elapsed (step S8: NO), returns to the step S7 and repeats the subsequent processing.
Specifically, the control unit 50 determines the number of sheets of paper for executing the separation operation at the time of receiving the paper according to the paper conditions including the type, basis weight and size of the paper used in the job. For example, when the paper is thin, the basis weight is low, or the length of the paper in the transport direction is short, the number of sheets for performing the separation operation at the time of receiving the paper is increased.
In this way, by determining the number of sheets of paper to be separated at the time of receiving the paper according to the paper conditions, the moisture remaining in the humidifying rollers 531a and 531b after the draining operation causes the paper to wrap. Can be prevented more reliably.

Then, when the predetermined number of sheets has elapsed (step S8: YES), the control unit 50 shifts to step S9 described later.

If it is determined in step S6 that the predetermined paper conditions are not met (step S6: NO), or if the predetermined number of sheets has elapsed in step S8 (step S8: YES), the control unit 50 of the job A normal operation (an operation that does not execute the separation operation when accepting paper) is executed for the remaining paper, and this process is terminated.

As described above, according to the present embodiment, the pair of humidifying rollers 531a and 531b that impart moisture to the paper when the paper is sandwiched and conveyed, and the water supply that contacts the humidifying rollers 531a and 531b to supply water. The amount of water in the rollers 532a, 532b, the draining rollers 533a, 533b provided so as to be in contact with and detachable from the water supply rollers 532a, 532b, and the humidifying rollers 531a, 531b is smaller than that in the first state. When switching to the second state, the control unit 50 is provided to perform a draining operation in which the draining rollers 533a and 533b are brought into contact with the water supply rollers 532a and 532b between the sheets.
Therefore, when the water content of the humidifying rollers 531a and 531b is switched from the first state to the second state, the draining operation is performed between the papers, so that the paper corners are folded or the paper is wrapped in the subsequent papers. It is possible to prevent such a problem.
Therefore, for example, when a job that humidifies thin paper or a job that does not humidify is performed after a job with a large amount of humidification, it is possible to prevent problems such as corner folding of paper and wrapping of paper in subsequent jobs.

Further, according to the present embodiment, the drain rollers 533a and 533b are roller members that rotate in contact with the surfaces of the water supply rollers 532a and 532b.
Therefore, the durability can be improved as compared with the draining member fixedly installed on the surfaces of the water supply rollers 532a and 532b.

Further, according to the present embodiment, the control unit 50 performs a draining operation from a state where the humidifying rollers 531a, 531b and the water supply rollers 532a, 532b are in contact with each other and the water supply rollers 532a, 532b and the draining rollers 533a, 533b are separated from each other. , The draining rollers 533a, 533b are brought into contact with the water supply rollers 532a, 532b and held for a predetermined time, and then the water supply rollers 532a, 532b are separated from the humidifying rollers 531a, 531b.
Therefore, the water supply rollers 532a, 532b and thus the humidifying rollers 531a, 531b can be separated from the water supply rollers 532a, 532b and the humidifying rollers 531a, 531b after the water adhering to the surfaces of the water supply rollers 532a, 532b and the humidifying rollers 531a, 531b are removed by the draining rollers 533a, 533b.

Further, according to the present embodiment, the control unit 50 determines the time for the drain rollers 533a and 533b to contact the water supply rollers 532a and 532b based on the water content of the humidifying rollers 531a and 531b and the humidification amount of the subsequent paper.
Therefore, a more appropriate draining operation can be performed.

Further, according to the present embodiment, if the paper received by the humidifying rollers 531a and 531b satisfies the predetermined conditions after the draining operation is executed, the control unit 50 separates the humidifying rollers 531a and 531b when receiving the paper.
Therefore, it is possible to prevent the paper from being wrapped due to the water remaining on the humidifying rollers 531a and 531b after the draining operation.

Specific details such as the configuration and control shown in the above embodiment can be appropriately changed without departing from the spirit of the present invention.

For example, in the draining operation (step S55) in the second initial operation, it is also preferable to adjust the time for contacting the draining rollers 533a and 533b with the surfaces of the water supply rollers 532a and 532b according to the environmental condition around the paper humidifying device 5. ..
For example, when the humidity around the paper humidifier 5 is higher than the set value, it is possible to control the time for contacting the drain rollers 533a and 533b with the surfaces of the water supply rollers 532a and 532b for a longer period of time.
By doing so, a more appropriate draining operation can be performed.

Further, in the draining operation, when the draining rollers 533a and 533b are brought into contact with the water supply rollers 532a and 532b, it is also preferable to change the pushing amount (crimping force) according to the amount of water adhering to the water supply rollers 532a and 532b. .. That is, when the amount of water adhering to the water supply rollers 532a and 532b is large, control such as making the pushing amount larger than the set value may be performed.
By doing so, the time required for draining can be shortened, and productivity can be further improved.

Further, in steps S7 and S8 of FIG. 4, the number of sheets for executing the separation operation at the time of receiving the sheets is determined according to the sheet conditions of the sheets used in the job. Depending on whether or not the predetermined condition is satisfied, it may be determined whether or not to execute the separation operation at the time of receiving the paper.
In this case, in addition to satisfying preset paper conditions (for example, paper type, basis weight, size, etc.) that are judged to be prone to wrapping of the tip, the predetermined conditions are after the initial operation is completed. Additional conditions such as being within a preset number of sheets are included.

Further, in the above embodiment, the configuration in which the drain rollers 533a and 533b are brought into contact with and separated from the water supply rollers 532a and 532b has been described as an example, but the drain rollers 533a and 533b are attached to the humidifying rollers 531a and 531b. The water draining rollers 533a and 533b may be provided on both the humidifying rollers 531a and 531b and the water supply rollers 532a and 532b so as to be in contact with and separated from each other.

Further, in the above embodiment, from the viewpoint of durability, the rotatable draining rollers 533a and 533b have been exemplified and described, but on the surfaces of the humidifying rollers 531a and 531b and the water supply rollers 532a and 532b. On the other hand, it may be a non-rotating member arranged so as to form a predetermined angle. For example, as shown in FIG. 8, plate-shaped members 538a and 538b such as blades or scrapers can be mentioned.
By doing so, it is possible to save energy as compared with the rotating draining member.

1 Image forming system 3 Image forming device 30 Control unit 38 Image forming unit 5 Paper humidifying device 50 Control unit 51 Interface 52 Transport unit 52a Transport path 53 Humidifying section 531a, 531b Humidifying rollers 532a, 532b Water supply rollers 533a, 533b Draining rollers (drainers) Element)
534 First pumping roller 535 Second pumping roller 536 Upper water storage section 537 Lower water storage section 538a, 538b Plate-shaped member (draining member)
61 1st drive unit 62 2nd drive unit PS1 upstream sensor PS2 downstream sensor 54 Paper processing unit 7 Paper processing device

Claims (8)

A pair of humidifying rollers that moisturize the paper when it is sandwiched and transported,
A water supply roller that contacts the humidifying roller to supply water,
A draining member provided so as to be in contact with at least one of the humidifying roller and the water supply roller.
When the water content of the humidifying roller is switched from the first state to the second state, which is less than the first state, the draining member is placed between the papers with respect to at least one of the humidifying roller and the water supply roller. And the control unit that performs the draining operation to make contact
Equipped with
The control unit
From the state where the humidifying roller and the water supply roller are in contact with each other and the draining member is separated from the humidifying roller and the water supply roller, the draining member is placed on at least one of the humidifying roller and the water supply roller as the draining operation. the contacted holds a predetermined time, then, sheet moisturizing device according to claim Rukoto is separated the dampening roller from the humidifying roller. The paper humidifying device according to claim 1, wherein the draining member is a humidifying roller or a roller member that rotates in contact with the surface of the water supply roller. The paper humidifying device according to claim 1, wherein the draining member is a plate-shaped member arranged so as to form a predetermined angle with respect to the surface of the humidifying roller or the water supply roller. One of claims 1 to 3 , wherein the control unit determines the time for the draining member to contact the humidifying roller or the water supply roller based on the water content of the humidifying roller and the humidifying amount of the subsequent paper. The paper humidifier according to item 1. One of claims 1 to 4 , wherein the control unit adjusts the time for contacting the draining member with the surface of the humidifying roller or the water supply roller according to the environmental condition around the paper humidifying device. The paper humidifier described in. The control unit according to any one of claims 1 to 5 , wherein when the paper received by the humidifying roller satisfies a predetermined condition after the execution of the draining operation, the control unit separates the humidifying roller when receiving the paper. The paper humidifier described. An image forming device that forms an image on paper,
The paper humidifying device according to any one of claims 1 to 6 , wherein water is applied to the paper on which an image is formed by the image forming device to humidify the paper.
An image forming system characterized by being equipped with. A pair of humidifying rollers that moisturize the paper when it is sandwiched and transported,
A water supply roller that contacts the humidifying roller to supply water,
A computer of a paper humidifier provided with a draining member provided so as to be in contact with and detachable from at least one of the humidifying roller and the water supply roller.
When the water content of the humidifying roller is switched from the first state to the second state, which is less than the first state, the draining member is placed between the papers with respect to at least one of the humidifying roller and the water supply roller. to function as a control unit for draining operation of contacting Te,
The control unit
From the state where the humidifying roller and the water supply roller are in contact with each other and the draining member is separated from the humidifying roller and the water supply roller, the draining member is placed on at least one of the humidifying roller and the water supply roller as the draining operation. the contacted holds a predetermined time and then, because of a program is separated the dampening roller from the humidifying roller.

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