JP2007279551A - Paper humidification device and image forming apparatus equipped therewith - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To eliminate the curl and the waviness of paper ejected from a fixing device by controlling the kind of paper, the basis weight of the paper or the moisture content of the paper to paper passing environment and stably supplying moisture fit to respective conditions to the paper. <P>SOLUTION: The paper humidification device has a pair of humidifying rollers forming a nip, and a water supply means for supplying water to the pair of humidifying rollers, and humidifies the paper by making the paper pass through the nip. In the device, the moisture content of the paper is variably controlled by variably setting the linear velocity of the humidifying roller corresponding to the kind of the paper passing through the nip. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a sheet humidifier that humidifies sheets and an image forming apparatus including the sheet humidifier.

  In an electrophotographic image forming apparatus, that is, a copying machine, a printer, a facsimile machine, or a multi-function machine having these functions, the paper is curled or deformed into a wavy shape as a result of the removal of moisture from the paper in the fixing process. Is a problem. As means for solving this problem, it has been proposed to humidify the paper after the fixing process (Patent Documents 1 and 2).

  In Patent Document 1, water vapor is blown onto a sheet, whereas Patent Document 2 discloses a method in which a pair of rollers forms a nip, and water is supplied to the roller while the sheet is humidified through the nip.

  In the sheet processing apparatus described in Patent Document 3, when the number of sheet bundles stacked on the first stacking tray is a predetermined number or more, the sheet bundle is divided into a small number of sheets and discharged to the first stacking tray by a bundle discharge roller. Thereafter, the sheet is transferred to the second stacking tray, and when the number of sheet bundles is reached, the next sheet bundle is divided into a small number of sheets and the sheet stacking position is changed and discharged to the first stacking tray. Thus, the sheets are stacked with good consistency in an offset state on the second stacking tray.

  The sheet processing apparatus described in Patent Document 4 rotates the feeding roller in the middle while feeding the sheet fed via the first path to the downstream side by the feeding roller, and switches the path by the switching member. Then, the sheet is fed once into the second path while avoiding a collision between the trailing edge of the switched back sheet and the leading edge of the next fed sheet, and then fed forward into the second path by rotating the feeding roller forward. And the next sheet fed together are fed into the saddle stitching compiler tray.

The post-fixing sheet adjusting device described in Patent Document 5 is a control system including a humidifying agent applying roller, a nip pressure adjusting assembly, and a controller.
Japanese Patent Application Laid-Open No. 2000-118849 US Pat. No. 5,264,899 JP-A-10-194568 JP 2006-8384 A US Pat. No. 6,052,553

  As similar to the paper humidifier described in Patent Document 2, the present applicant has proposed a paper humidifier in Japanese Patent Application No. 2004-184848 that supplies water to one roller of a roller pair. The paper humidifying device of the above-mentioned patent application has a simpler structure than that of Patent Document 2, is smaller, and is more suitable for incorporation into an image forming apparatus.

  Patent Documents 1 and 2 and Japanese Patent Application No. 2004-184848 describe only a paper humidifier. Patent Documents 3 and 4 describe a superposing and conveying unit for a plurality of sheets. Patent Document 5 does not control the humidification amount by changing the nip amount according to the paper type, basis weight, environment, and other conditions. Further, although the roller pair is rotated and moisture is supplied to the sheet by the nip, the humidification amount control is not performed by changing the roller rotation speed.

  The paper undulation can be reduced by humidifying the paper discharged from the heat fixing device with the paper humidifying device. However, humidification of the paper significantly reduces the stiffness (rigidity) of the paper. For this reason, in the paper discharge means and the paper post-processing device connected to the image forming apparatus, paper conveyance failures such as jams frequently occur and reliability is lowered.

  An object of the present invention is to solve the above-described problem in sheet humidification using a humidification roller pair.

  The object is achieved by the following invention.

1. A humidifying roller pair that forms a nip, and a water supply unit that supplies water to the humidifying roller pair, and a paper humidifying device that humidifies the paper by passing the paper through the nip.
A paper humidifying device that variably controls the water content of the paper by variably setting the linear velocity of the humidifying roller pair corresponding to the type of paper passing through the nip.

2. An image forming apparatus main body for forming an image on paper;
The paper humidifying device according to 1 above,
A paper post-processing device that performs post-processing on the paper discharged from the paper humidifying device;
An image forming apparatus comprising:

  According to the first aspect of the invention, by changing the linear speed of the humidifying roller pair of the paper humidifying device, the paper type of the paper, the basis weight, or the water content of the paper with respect to the paper passing environment is controlled, and suitable for each condition. By stably supplying moisture to the paper, curling and undulation of the paper discharged from the heat fixing device is eliminated, and a paper with good flatness can be obtained.

  According to the second aspect of the invention, in the image forming apparatus in which the image forming apparatus main body, the paper humidifying apparatus, and the paper post-processing apparatus are connected and arranged, the paper humidifying apparatus applies the paper to the paper discharged from the heat fixing device of the image forming apparatus main body. Curling, waviness and the like are eliminated, and a sheet with good flatness is sent to the sheet post-processing apparatus, and a high-quality booklet is produced after the post-processing.

  Hereinafter, the present invention will be described with reference to embodiments, but the present invention is not limited to the embodiments.

  FIG. 1 is an overall view of an image forming apparatus according to an embodiment of the present invention. The image forming apparatus includes an image forming apparatus main body A, a sheet humidifying apparatus B, and a sheet post-processing apparatus (finisher) FS.

[Image forming device body]
The image forming apparatus main body A has an automatic document feeder 1 and an image reading unit 2 in the upper part, and the lower part is constituted by a printer unit.

  In the printer section, 3 is a paper storage section for storing the paper S. An image is formed on the sheet S in the printer engine 5 that forms a toner image on the photoconductor 4 by an electrophotographic process in which the photoconductor 4 is charged, exposed, and developed. Is fixed. The fixing device 6 forms a nip for transporting the paper S by a heating roller 6b and a pressure roller 6c having a built-in heat source 6a, and melts the toner by heating and pressurizing the paper S while transporting the paper S. To settle.

  The sheet S is fed from the sheet storage unit 3 by the first sheet feeding unit 3a, and after being temporarily stopped by the second sheet feeding unit 3b, the sheet is fed and image formation is performed. The paper is discharged from the paper discharge port by the roller 8.

  As the transport path of the paper S, a paper feed path 7 from the paper storage unit 3 to the printer engine 5, a transport path 9 a from the printer engine 5 through the fixing device 6 and the paper discharge roller 8 to the paper discharge port and reverse transport are performed. A back surface conveyance path 9b is provided.

  As the image forming mode, there are a single-side face-down discharge mode, a single-side face-up discharge mode, and a double-side mode. In the single-side face-down discharge mode, an image is formed on one side and the sheet S that has passed through the fixing device 6 is After the front and back are reversed by the reversing process, the paper is conveyed by the paper discharge roller 8 and discharged.

  In the single-sided face-up paper discharge mode, the paper S on which an image is formed on one side and transported through the transport path 9a is transported and discharged by the paper discharge roller 8 as it is.

  In the double-sided mode, the sheet S on which one side has been formed and has passed through the fixing device 6 travels downward and proceeds to the back surface conveyance path 9b. .

  A back side image is formed on the back side of the re-feed paper S by the printer engine 5, and the paper S on which the back side image is formed passes through the fixing device 6 and is conveyed and discharged by the paper discharge roller 8.

  Reference numeral 10 denotes an operation unit, which can set various modes in the image forming apparatus main body A and an output mode using the sheet post-processing device FS by operating the operation unit 10.

  The control unit C1 disposed in the image forming apparatus main body A is connected to the control unit C2 of the paper humidifying device B and the control unit C3 of the paper post-processing device FS via the communication unit C4.

  The sheet S discharged from the image forming apparatus main body A is conveyed to a sheet post-processing device (finisher) FS via a sheet humidifying device B. The paper humidifier B will be described later.

[Paper post-processing device]
The paper post-processing device FS performs various post-processing devices for the paper S discharged from the image forming apparatus main body A. Are collectively referred to.

  As an embodiment of the sheet post-processing apparatus FS, a glue binding machine will be described as a representative.

  The gluing bookbinding machine includes a sheet introducing unit 21, a sheet discharging unit 22, a sheet bundle storing unit 23, a sheet bundle conveying unit 24, a glue applying unit 25, a cover sheet supplying unit 26, a cover sheet cutting unit 27, a cover sheet exterior unit (case binding unit). 28 and alignment means 29 are provided. Each of these means is arranged in a column in a substantially vertical direction in the main body of the gluing bookbinding machine.

  The paper S introduced into the paper introduction means 21 is branched into either the paper discharge means 22 or the paper bundle storage means 23 by the switching gate 200.

  When the sheet conveyance to the sheet discharge unit 22 is set, the switching gate 200 blocks the sheet conveyance path 201 to the sheet bundle conveyance unit 24 and opens the sheet conveyance path 202 to the sheet discharge unit 22. The paper S passing through the paper transport path 202 of the paper discharge means 22 is transported upward and stored in the uppermost fixed paper discharge table 221 of the paper post-processing device FS.

  The sheets S branched and conveyed to the left in the drawing on the downstream side in the sheet conveyance direction by the switching gate 200 are stored in a predetermined position of the sheet bundle storage unit 23 and sequentially stacked, and a predetermined number of sheets are subjected to width alignment and vertical alignment. A sheet bundle Sa composed of the sheets S is formed.

  The sheet bundle Sa stacked on the sheet placing table 231 of the sheet bundle storage unit 23 is conveyed obliquely downward, and then is grasped by the grasping unit 241 of the sheet bundle conveying unit 24, and the sheet bundle is held while the sheet bundle Sa is grasped. It is turned so that the surface (back part) on which the paste is applied to Sa is turned downward and stopped at a predetermined position.

  The glue applying unit 25 includes a glue applying roller 251, a glue container 252, a movable body 253 that supports the glue container 252 and can move from an initial position on the back side of the glue binding machine to a glue application position on the front side. .

  The cover sheet K stored in the cover sheet supply unit 26 passes through the sheet conveyance path 261 via the cover sheet cutting unit 27 and is conveyed to the cover sheet exterior unit 28, and then the rear end portion of the cover sheet K is predetermined by the cover sheet cutting unit 27. Cut to the head. The cutting length of the cover sheet K is a length obtained by adding the thickness of the back portion of the sheet bundle Sa to the length of two sheets in the traveling direction of the sheet S.

  The cover cover means 28 receives and conveys the cover sheet K supplied from the cover sheet supply means 26, stops it at a predetermined position, and then performs positioning in the width direction by the aligning means 29. The cover cover means 28 moves the movable casing 282 to the upper position by the elevating means 281, and in the raised position, the center portion of the cover sheet K placed on the pressure member 283 is the glue application surface N of the sheet bundle Sa. It is pressed and adhered to

  By the downward movement of the pressure member 283 facing the back portion of the sheet bundle Sa and the movement of a pair of symmetrical bending members 284 arranged on the upper part of the cover sheet exterior means 28, the adhesive application surface N side of the sheet bundle Sa The cover sheet K is bent along the edge, and the sheet bundle Sa with the cover sheet K mounted on the front and back surfaces of the sheet bundle Sa is formed.

  After the cover sheet K folding process is finished, the cover cover exterior means 28 is lowered and retracted by the descending drive of the lift means 281, and then the discharge belt 285 that has been retracted to the outside in the width direction of the cover sheet K is retracted together with the retracting means 29. It moves to the inner side in the width direction below the bundle Sa and stops. Thereafter, when the holding by the gripping means 241 is released, the sheet bundle Sa descends and stops at a position where the lower back portion of the sheet bundle Sa contacts the upper surface of the discharge belt 285. The rotating discharge belt 285 discharges the booklet that has been subjected to the case binding process by sticking the cover K to the sheet bundle Sa to the outside of the apparatus.

[Paper humidifier]
FIG. 2 is a cross-sectional view of the sheet humidifying device B in the embodiment of the present invention.

  The sheet humidifier B includes a sheet introduction unit 100, a humidification unit 110, and a bypass transport unit 120.

  The sheet S on which the image is formed by the image forming unit of the image forming apparatus main body A is discharged through the fixing device 6 and the discharge roller 8, introduced into the sheet introducing unit 100 of the sheet humidifying apparatus B, and sandwiched between the conveying rollers 101. Are transported.

  The switching gate 102 disposed downstream of the conveyance roller 101 in the sheet conveyance direction determines whether to convey the sheet S to the lower sheet humidification conveyance path 103 or to convey the sheet S to the upper bypass conveyance path 104. Select and switch.

  The paper S introduced into the paper humidification conveyance path 103 is nipped between the conveyance rollers 105 and 106 and conveyed, and is sent to the humidification unit 110.

  The sheet S carried into the humidifying unit 110 is nipped between the conveying rollers R1 and R2 and conveyed in a U-turn shape, and is nipped by a pair of humidifying rollers 111A and 111B that rotate by pressing and humidifying. Then, the paper passes through the transport path 116 and is sandwiched and transported by the transport rollers R3 and R4, passes through the transport path 107, and is sent to the transport roller 121 of the bypass transport unit 120.

  112A and 112B are water supply rollers, 113A and 113B are regulation rollers, 114A and 114B are water supply tanks, 115 is a water storage tank, 116 is a conveyance path, and 117A and 117B are fans.

  Details of the humidifying unit 110 will be described in detail with reference to FIG.

  The paper S passing through the bypass transport path 104 or the paper S discharged from the humidifying section 110 and passing through the transport path 107 is introduced into the transport roller 121 of the bypass transport unit 120. The sheet S conveyed by the conveyance roller 121 passes through the conveyance path 122, is conveyed by the conveyance rollers 123 and 124, and the paper discharge roller 125, and is discharged outside the apparatus.

  Further, decurling means 126 and 127 for correcting the curl of the paper S are arranged in the bypass conveyance unit 120. The decurling means 126 and 127 are each composed of a plurality of roller groups, and the curl is corrected by being sandwiched and passed by these roller groups.

  The paper S transported by the transport roller 123 passes through the decurling means 126 by switching the transport path by the switching gate 128 to correct the curl, and further passes through the decurling means 127 by switching the transport path by the switching gate 129. It will be corrected.

[Humidification part]
FIG. 3 is a cross-sectional view of the humidifying unit 110.

  In the figure, reference numerals 111A and 111B denote humidifying rollers that form a pair of rollers that apply water to the paper S and humidify the paper S, both of which are porous on shafts 111Aa and 111Ba made of a rigid body such as metal or hard resin. Porous layers 111Ab and 111Bb made of porous urethane rubber or the like are formed.

  The porous layers 111 </ b> Ab and 111 </ b> Bb receive a supply of water from the surface, and form a porous surface that applies moisture to the paper S and humidifies it.

  112A is a water supply roller as water supply means for contacting the humidifying roller 111A to supply water W, such as a shaft core 112Aa made of a rigid body such as metal or hard resin, porous urethane rubber formed on the shaft core 112Aa, etc. It is comprised with the roller which consists of porous layer 112Ab which consists of.

  Similarly to the water supply roller 112A, the water supply roller 112B also includes an axial core 112Ba and a porous layer 112Bb.

  The water supply rollers 112A and 112B are preferably provided with the porous layers 112Ab and 112Bb as described above in order to provide quick water supply to the humidifying rollers 111A and 111B at the time of activation. It is not always necessary, and a material having a hydrophilic surface that does not absorb water and can retain water on the surface, for example, a roller made of metal, a resin subjected to hydrophilic treatment, or solid rubber can be used. .

  113A and 113B are restricting rollers constituting restricting means, and are restricting members made of a rigid body such as a round bar-like metal or hard resin. The regulation roller 113A is in pressure contact with the water supply roller 112A, and the regulation roller 113B is in pressure contact with the water supply roller 112B to suppress moisture contained in the porous layers 112Ab and 112Bb and regulate the amount of moisture supplied to the paper S. In other words, the regulating rollers 113A and 113B are in pressure contact with the porous layers 112Ab and 112Bb of the humidifying rollers 111A and 111B, respectively, and deform the porous layers 112Ab and 112Bb to squeeze the water contained in the porous layers 112Ab and 112Bb. As a result, the amount of water applied to the sheet S is regulated, the sheet S is moderately humidified, and stickiness of the sheet S due to excessive humidification is prevented. By adjusting the contact pressure of the regulating rollers 113A and 113B, appropriate humidification is possible.

  Fans 117A and 117B arranged on both sides of the conveyance path 116 blow air to both surfaces of the paper S being humidified and conveyed by the humidifying rollers 111A and 111B, and dry excess water W adhering to the surface of the paper S. The sheet S is removed and held in a proper water-containing state. This prevents water W from adhering to the conveying means such as the conveying roller and the guide plate by the sheet S conveyed after the humidification process, and the sheet conveyance failure and the apparatus member caused by the sticking of the sheet S due to excessive water W adhesion. Problems such as malfunctions and reduced service life are eliminated.

  The humidifying rollers 111A and 111B are driven by a motor (not shown) to rotate as indicated by arrows, and the water supply rollers 112A and 112B and the regulation rollers 113A and 113B are driven to rotate.

  The sheet S conveyed by the humidifying rollers 111A and 111B is humidified with water that has exuded from the porous layer at the nip NP between the humidifying rollers 111A and 111B. The amount of water supplied to the paper S is regulated to an appropriate amount by squeezing with the regulation rollers 113A and 113B. The pressure at which the regulating rollers 113A and 113B come into pressure contact with the water supply rollers 112A and 112B is appropriately set. That is, based on the paper type setting of the paper S in the operation unit 10 of the image forming apparatus main body A and the output of the environmental sensor for detecting the humidity and temperature, the control means uses the lines of the water supply rollers 112A and 112B of the regulation rollers 113A and 113B. It is preferable to set the speed and pressure contact pressure appropriately.

  Further, it is possible to implement a configuration in which the nip NP between the humidifying rollers 111A and 111B is opened to set a mode in which the humidifying process is not performed.

  The water supply roller 112A is immersed in the water W stored in the water supply tank 114A. The water supply roller 112B is immersed in the water W stored in the water supply tank 114B.

  The water tanks 114A and 114B and the water tank 115 disposed below are connected by a water pipe and a water pump (not shown), and the water W in the water tank 115 is supplied to the water tanks 114A and 114B.

  Depending on the type and thickness of the paper S and the moisture content of the paper S introduced into the paper humidifying device B, the paper S may be curled even if the humidification process is performed. In addition, undulation may occur. When there is a possibility that curling or undulation will occur, the switching gates 128 and 129 are operated by a solenoid (not shown), and the sheet S is advanced to the curved conveyance path of the decurling means 126 and 127. Accordingly, the moisture content of the paper S becomes uniform in the thickness direction, and curling and undulation are sufficiently prevented.

  When there is no fear of such undulations, the switching gates 128 and 129 can be set to the initial position, and the sheet S can be moved straight to increase the processing efficiency.

  The operation of the switching gates 128 and 129 is preferably performed based on the setting of the paper type in the operation unit 10 and the output of an environmental sensor that detects humidity and temperature.

  Further, when the humidification process is not performed, a configuration in which the nip NP between the humidification rollers 111A and 111B is opened to prevent the deformation of the humidification rollers 111A and 111B is possible.

[Driving means for humidification section]
FIG. 4 is a front view of the driving means of the humidifying unit 110.

  The first driving means using the motor M1 as a driving source rotates the gear G12 fixed to one end of the humidifying roller 111A via the gear G1O and the intermediate gear G11. Further, the intermediate gear G11 is fixed to the other end of the humidifying roller 111A and the intermediate gear G11 ′ that is symmetrical to the intermediate gear 11 that is fixed to the other end of the through shaft J1 that fixes the intermediate gear G13 by rotating the intermediate gear G13. The gear G12 ′ symmetrical to the gear G12 is rotated. Therefore, both ends of the humidifying roller 111A are driven and rotated through the gears by driving the motor M1.

  The second driving means using the motor M2 as a driving source rotates the gear G23 fixed to one end of the water supply roller 112A via the gear G2O and the intermediate gears G21 and G22. Further, the intermediate gear G21 rotates a gear G26 fixed to one end of the water supply roller 112B via the intermediate gears G24 and G25. In addition, the intermediate gear G21 is a gear fixed to the other end of the water supply roller 112A via the intermediate gear G21 'symmetrical to the intermediate gear 21 fixed to the other end of the through shaft J2 to which the intermediate gear G21 is fixed, and a gear train. A gear G23 ′ symmetrical to G23 and a gear G26 ′ symmetrical to gear G26 fixed to the other end of water supply roller 112B are rotated. Therefore, both ends of the water supply rollers 112A and 112B are driven and rotated by the driving of the motor M2 through the gears.

  The third driving means using the motor M3 as the driving source rotates the gear G32 fixed to one end of the regulating roller 113B via the gear G3O and the intermediate gear G31. The intermediate gear G31 rotates the intermediate gear G33 and rotates the gear G35 fixed to one end of the regulating roller 113A via the belt Be and the intermediate gear G34. The intermediate gear G33 is a gear fixed to the other end of the regulating roller 113A via a gear train and an intermediate gear G33 'symmetrical to the intermediate gear 33 fixed to the other end of the through shaft J3 to which the intermediate gear G33 is fixed. A gear G35 'symmetrical to G35 and a gear G32' symmetrical to gear G32 fixed to the other end of the regulating roller 113B are rotated. Therefore, both ends of the regulation rollers 113A and 113B are driven and rotated by the drive of the motor M3 via the gears.

  FIG. 5 is a block diagram showing the control of the humidifying rollers 111A and 111B of the sheet humidifying device B.

  The control unit C1 disposed in the image forming apparatus main body A shown in FIG. 1 operates the control unit C2 of the paper humidifying device B via the communication unit C4.

  In the operation unit 10, paper types such as plain paper, high-quality paper, and glossy coated paper are selected and set. In the operation unit 10, paper basis weight such as thick letters, regular paper, and thin letters is selected and set. In some cases, environmental temperature and humidity are set. After performing these operations, the determination of the paper humidification control is input.

  The control means C1 and C2 are a first drive means using the motor M1 as a drive source, a second drive means using the motor M2 as a drive source, an ON / OFF state of the third drive means using the motor M3 as a drive source, and a nip NP. The moisture content of the paper S is variably controlled by variably setting the linear speeds of the humidifying rollers 111A and 111B corresponding to the paper type, basis weight, environmental temperature and humidity, etc.

  FIG. 6 is a graph showing the relationship between the linear velocity of the humidifying rollers 111A and 111B and the moisture content when gloss coated paper is passed.

  When the humidification process is not performed, that is, when the paper passes through the bypass conveyance unit 120 of the paper humidifier B, the moisture content is substantially constant over a linear speed of 4 to 1000 mm / S, as indicated by the line segment a. .

  When performing the humidification process, that is, when passing through the humidifying unit 110 of the paper humidifying device B, the moisture content is about 4 during the linear speed range of 40 mm / S to 1000 mm / S, as shown by the line b. % To about 8%.

  The moisture content is measured by the following steps.

  (1) Leave the paper S all day and night in an environment of temperature 20 ° C. and humidity 50% RH.

  (2) The mass w1 of the left sheet S is measured.

  (3) The left sheet S is accommodated in a drying box at 90 ° C. and dried for 2 hours.

  (4) The paper S is taken out and the mass w2 after drying is measured.

  (5) The water content is calculated by the formula (w1-w2) / w1 × 100 = water content (%).

  FIG. 7 is a graph showing the relationship between the linear velocity of the humidifying rollers 111A and 111B and the moisture content.

  The moisture content of the paper S was measured by setting the linear speeds of the humidifying rollers 111A and 111B to two types of 400 mm / s and 800 mm / s.

Line segment a indicates the moisture content at a linear speed of 400 mm / s and 800 mm / s in the case of plain paper for PPC (64 g / m ² ). The line segment b indicates the moisture content at 400 mm / s and 800 mm / s at the line speed in the case of fine paper (81.4 g / m ² ). Line segment c indicates each moisture content in glossy coated paper (81.4 g / m ² ).

  By making the linear speed of the humidifying rollers 111A and 111B variable, the moisture content of the paper S is controlled by the optimum linear speed for the paper type, basis weight, or paper passing environment of the paper S, and moisture suitable for each condition Is stably supplied to the paper S, the curling and undulation of the paper S discharged from the fixing device 6 is eliminated, and a paper with good flatness can be obtained. Further, it is possible to suppress a decrease in conveyance performance due to excessive water supply to the paper S.

  In the embodiment of the present invention, the image forming apparatus in which the sheet humidifying apparatus B and the sheet post-processing apparatus FS are connected to the copying machine has been described. However, the image forming apparatus main body such as a light printing machine, a printer, a facsimile machine, and a digital multifunction machine The present invention can also be applied to an image forming apparatus in which a sheet humidifier B and a sheet post-processing apparatus FS are connected to A.

1 is an overall view of an image forming apparatus according to an embodiment of the present invention. Sectional drawing of the paper humidification apparatus in embodiment of this invention. Sectional drawing of a humidification part. The front view of the drive means of a humidification part. The block diagram which shows the humidification control of a paper humidification apparatus. The graph which shows the relationship between the linear velocity of a humidification roller, and a moisture content when glossy coated paper passes. The graph which shows the relationship between the linear velocity of a humidification roller, and a moisture content.

Explanation of symbols

6 fixing device 10 operation unit 103 sheet humidification conveyance path 104 bypass conveyance path 110 humidification section 111A, 111B humidification roller 112A, 112B water supply roller 113A, 113B regulation roller 114A, 114B water supply tank 115 water storage tank 120 bypass conveyance section 23 sheet bundle storage means 24 Sheet bundle transport means 25 Glue application means 26 Cover cover supply means 28 Cover cover exterior means (case binding means)
A Image forming apparatus main body B Paper humidifier C1, C2, C3 Control means FS Paper post-processing device (finisher)
M1, M2, M3 Motor S Paper

Claims (2)

A humidifying roller pair that forms a nip, and a water supply unit that supplies water to the humidifying roller pair, and a paper humidifying device that humidifies the paper by passing the paper through the nip.
A paper humidifying device that variably controls the water content of the paper by variably setting the linear velocity of the humidifying roller pair corresponding to the type of paper passing through the nip. An image forming apparatus main body for forming an image on paper;
A paper humidifier according to claim 1;
A paper post-processing device that performs post-processing on the paper discharged from the paper humidifying device;
An image forming apparatus comprising:

Images