JP2014091605A - Sheet humidifier and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a simply-configured sheet humidifier for uniformly humidifying two sides of a sheet, and an image forming apparatus using the sheet humidifier.SOLUTION: An upper-surface humidification part 100a and a lower-surface humidification part 100b have the same configuration. In the upper-surface humidification part 100a, a water-supply roll 130a obtains moisture W1 from a water tank 150a, in which a distance L1 to a position KP1 where a humidifying roll 110a humidifies an upper surface of a sheet with the moisture W1 is 2×r1×θ1a+2×r2×θ2a+2×r3×θ3a. In the lower-surface humidification part 100b, a water-supply roll 130b obtains moisture W2 from a water tank 150b, in which a distance L2 to a position KP2 where a humidifying roll 110b humidifies a lower surface of a sheet with the moisture W2 is 2×r1×θ1b+2×r2×θ2b+2×r3×θ3b. In a sheet humidifier 1B, a ratio of the distance L1 to the distance L2 is set to fall within a predetermined range.

Description

  The present invention relates to a sheet humidifier and an image forming apparatus.

  In an image forming apparatus such as a copying machine or a printer, a toner image formed with a photosensitive member is transferred onto a sheet, and the toner image is fixed by heating the sheet while applying pressure to the sheet. In the paper on which such a toner image is fixed, moisture is evaporated by heating, and the paper is replenished with water using, for example, a paper humidifier.

  Further, in an image forming apparatus having a bookbinding apparatus, a booklet that is bound using paper that has evaporated moisture by heating may absorb moisture in the air over time and be deformed to wave. In order to avoid such problems, a paper humidifier is used (see Patent Documents 1 to 4).

JP 2012-024953 A JP-A-11-161108 JP 2006-193332 A JP 2007-279550 A

In the image forming apparatus using the sheet humidifying apparatus having the conveyance path for conveying the sheet in the vertical direction as described in Patent Document 1 and Patent Document 4 described above, the image forming apparatus humidifies moisture on the first surface of the sheet. The front and back sides of the paper are uniformly humidified by arranging the first surface humidifying unit and the second surface humidifying unit that humidifies moisture on the second surface, which is the back surface of the first surface, symmetrically on the left and right sides of the conveyance path. However, it is necessary to once transport the paper in the vertical direction in order to humidify the paper transported in the horizontal direction, and to return the paper transport direction to the horizontal direction again after passing through the paper humidifier, The scale of the device becomes large.
Further, in the image forming apparatus using the sheet humidifying apparatus having the conveyance path for conveying the paper in the horizontal direction as described in Patent Document 2 and Patent Document 3 described above, the first sheet of the paper is caused by gravity. The problem is that the first surface humidifying unit that humidifies moisture on the surface and the second surface humidifying unit that humidifies moisture on the second surface, which is the back surface of the first surface, cannot be arranged symmetrically above and below the conveyance path, respectively. There is.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a sheet humidifier that uniformly humidifies the front and back of a sheet with a simple configuration and an image forming apparatus using the same.

The sheet humidifying device of the present invention has a conveyance path for conveying a sheet in the horizontal direction, and includes a first surface humidifying unit that humidifies moisture on the first surface of the sheet, and a second surface that is the back surface of the first surface. A second surface humidifying unit for humidifying water, wherein the first surface humidifying unit and the second surface humidifying unit are a water supply roll for supplying water, and an intermediate roll for obtaining water in contact with the water supply roll And a humidifying roll that contacts the intermediate roll while transporting the paper to obtain moisture and humidifies the surface of the paper, respectively, and has a water supply position of the water supply roll of the first surface humidifying unit. The first distance that the moisture follows from the moisture humidifying position of the humidifying roll to the moisture humidifying position of the humidifying roll and the second distance that the moisture follows from the moisture supplying position of the water supplying roll of the second surface humidifying unit to the moisture humidifying position of the humidifying roll A paper humidifier characterized by the same distance.
Further, the sheet humidifying device of the present invention is characterized in that a ratio of the first distance traced by the moisture and the second distance traced by the moisture satisfies the following expression.
Here, r1 is the radius of the humidifying roll, r2 is the radius of the intermediate roll, r3 is the radius of the water supply roll, and θ1a and θ1b are the humidifying roll and the second surface of the first surface humidifying unit. Each of the humidifying rolls in the humidifying section represents a central angle in the rotation direction until the moisture comes into contact with the intermediate roll to obtain moisture and humidifies the first face, and θ2a and θ2b are the first face humidifying sections. The intermediate roll and the intermediate roll of the second surface humidifying unit represent the central angles in the rotational direction until they contact the water supply roll to obtain moisture and contact the humidifying roll, respectively, θ3a and θ3b are The water supply roll of the first surface humidification unit and the water supply roll of the second surface humidification unit each represent a central angle in the rotation direction until water is supplied and contact with the intermediate roll, and θ2a + θ2b = The condition is 2 × π, θ1a−θ2a + θ3a = 2 × π, and θ1b−θ2b + θ3b = π.

Further, in the sheet humidifying device of the present invention, the first surface humidifying unit has the water supply roll disposed on the downstream side in the conveyance direction of the humidifying roll, and a member for limiting the amount of water supply is disposed on the water supply roll. It is characterized by.
The member for limiting the amount of water supply is a roll member.

The paper humidifier of the present invention is characterized in that the θ2a is 5 / 8π ≦ θ2a ≦ 7 / 8π, and the θ2b is 9 / 8π ≦ θ2b ≦ 11 / 8π.
Further, the sheet humidifying device of the present invention is characterized in that a ratio of the first distance traced by the moisture and the second distance traced by the moisture satisfies the following expression.
Here, r1 is the radius of the humidifying roll, r2 is the radius of the intermediate roll, r3 is the radius of the water supply roll, and θ1a and θ1b are the humidifying roll and the second surface of the first surface humidifying unit. Each of the humidifying rolls in the humidifying section represents a central angle in the rotation direction until the moisture comes into contact with the intermediate roll to obtain moisture and humidifies the first face, and θ2a and θ2b are the first face humidifying sections. The intermediate roll and the intermediate roll of the second surface humidifying unit represent the central angles in the rotational direction until they contact the water supply roll to obtain moisture and contact the humidifying roll, respectively, θ3a and θ3b are The water supply roll of the first surface humidification unit and the water supply roll of the second surface humidification unit each represent a central angle in the rotation direction until water is supplied and contact with the intermediate roll, and θ2a + θ2b = The condition is 2 × π, θ1a−θ2a + θ3a = 0, and θ1b−θ2b + θ3b = π.
The paper humidifier of the present invention is characterized in that the θ2a is 9 / 8π ≦ θ2a ≦ 11 / 8π, and the θ2b is 5 / 8π ≦ θ2b ≦ 7 / 8π.
In the sheet humidifying apparatus of the present invention, the relationship between r2 and r3 is r2 ≦ r3.
In the sheet humidifying apparatus of the present invention, the relationship between r1 and r2 is r2 ≦ r1.

  In the paper humidifying device of the present invention, the humidifying roll and the water supply roll are made of nitrile rubber, and the intermediate roll is made of metal.

  An image forming apparatus according to the present invention includes: an image forming apparatus main body that forms an image on a paper; the paper humidifying apparatus according to any one of the above that humidifies paper discharged from the image forming apparatus main body; and the paper humidifying apparatus. And a bookbinding apparatus for bookbinding the humidified paper.

  According to the present invention, it is possible to provide a paper humidifier that uniformly humidifies the front and back of a paper with a simple configuration and an image forming apparatus using the same.

1 is a schematic configuration diagram illustrating an image forming apparatus according to an embodiment. 1 is a schematic configuration diagram illustrating an image forming apparatus main body according to an embodiment. It is a schematic block diagram which shows the paper humidification apparatus of embodiment. It is a schematic diagram which shows arrangement | positioning of the paper humidification apparatus of embodiment. It is a schematic diagram which shows an example of a paper humidification apparatus. It is a schematic block diagram which shows the bookbinding apparatus of embodiment. It is a 2nd schematic diagram which shows arrangement | positioning of the paper humidification apparatus of embodiment.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram of an image forming apparatus 1 according to the embodiment. An image forming apparatus 1 shown in FIG. 1 introduces an image forming apparatus main body 1A that forms an image on a sheet P as an example of a recording material, and a sheet P discharged from the image forming apparatus main body 1A, and humidifies the sheet P. The sheet humidifying device 1B is configured to include the sheet P discharged from the sheet humidifying device 1B, and the bookbinding apparatus 1C that binds the sheet P.

  The image forming apparatus main body 1A of the embodiment will be described. FIG. 2 is a schematic configuration diagram of the image forming apparatus main body 1A. An image forming apparatus main body 1A shown in FIG. 2 includes a control unit 2, image forming units 3K, 3Y, 3M, and 3C, a transfer unit 50, a fixing unit 60, and a paper storage unit 80. Based on this, an image is formed on a sheet P as a recording medium.

  In the image forming units 3K to 3C, black (K), yellow (Y), magenta (M), and cyan (C) toner images are formed. As shown in FIG. 2, each of the image forming units 3K to 3C has the configurations of the photoreceptors 10K to 10C, the charging units 20K to 20C, the exposure units 30K to 30C, the developing units 40K to 40C, and the cleaning units 70K to 70C. Have. In addition, when it is not necessary to distinguish these configurations, for example, the image forming units 3K to 3C are simply referred to as the image forming unit 3.

  The control unit 2 includes an arithmetic device such as a CPU (Central Processing Unit) and a memory, and controls the operation of each component of the image forming apparatus 1. In the embodiment, the control unit 2 also controls the operation of each component of the sheet humidifying device 1B and the bookbinding device 1C.

  The photoreceptor 10 (10K to 10C) is a cylindrical rotating body having a photosensitive layer formed of an organic photosensitive material for holding an image and rotating in the direction of the arrow shown in FIG.

  The charging unit 20 (20K to 20C) applies a predetermined charging voltage using a charging roll that rotates in contact with the surface of the photoconductor 10. The charging unit 20 includes a contact charging method in which the photosensitive member 10 is charged by using a brush or the like, or a non-contact charging method in which the photosensitive member 10 is charged using corona discharge.

  The exposure unit 30 (30K to 30C) irradiates the surface of the photoconductor 10 charged by the charging unit 20 with light according to image data to form an electrostatic latent image having a latent image potential based on a potential difference. . The electrostatic latent image moves to a position where the developing unit 40 is disposed as the photoconductor 10 rotates.

  The developing unit 40 (40K to 40C) has a rotating developing roll 41 (41K to 41C), and the toner adsorbed on the developing roll 41 is transferred to the photoconductor 10. That is, the toner moves to the surface of the photoconductor 10 due to a potential difference between the electrostatic latent image formed on the photoconductor 10 and the charged toner. In this way, a toner image is formed on the photoconductor 10, and the toner image moves to a position where the transfer unit 50 is disposed as the photoconductor 10 rotates.

  The transfer unit 50 includes an intermediate transfer belt 51, a backup roll 52, a plurality of support rolls 53, a primary transfer roll 54 (54K to 54C), and a secondary transfer roll 55. The toner image on the intermediate transfer belt 51 is transferred to the paper P transported by the transport roller 91 by the transfer unit 50, and the paper P is transported to the fixing unit 60.

  The intermediate transfer belt 51 is stretched by a support roll 53 and a backup roll 52, and is rotated by driving the support roll 53, for example. The primary transfer roll 54 is provided so as to face the photoreceptor 10, and is disposed so that the intermediate transfer belt 51 is sandwiched between the primary transfer roll 54 and the photoreceptor 10. The primary transfer roll 54K faces the photoconductor 10K, and the same applies to the other portions.

  Each of the primary transfer rolls 54K to 54C is driven according to the rotation of the intermediate transfer belt 51, and presses the intermediate transfer belt 51 while rotating. The toner images formed on the photoreceptors 10K to 10C are transferred so as to be superimposed on the surface of the intermediate transfer belt 51. The secondary transfer roll 55 is provided so as to face the backup roll 52. The intermediate transfer belt 51 and the paper P are sandwiched between the secondary transfer roll 55 and the backup roll 52, and the toner image transferred to the intermediate transfer belt 51 is transferred to the paper P.

  The fixing unit 60 includes a heating roll 61 having a heat source and a pressure roll 62 provided to face the heating roll 61, and fixes an unfixed toner image on the paper P by heating and pressing. . The paper P on which the toner image is fixed by the fixing unit 60 is conveyed by the conveyance roll 91.

  The cleaning unit 70 removes the toner remaining on the surface of the photoconductor 10 after the toner image is transferred to the paper P. The paper storage unit 80 stores a plurality of papers P. The paper P is taken out from the paper storage unit 80 by the paper supply roll 90 and conveyed to the transfer unit 50.

  Next, the paper humidifying device 1B of the embodiment will be described. FIG. 3 is a schematic configuration diagram of the paper humidifier 1B. The sheet humidifying device 1B according to the embodiment has a conveyance path for conveying a sheet in the horizontal direction, and includes an upper surface humidifying unit 100a as a first surface humidifying unit that humidifies moisture on the upper surface, which is the first surface of the sheet P, and the first. The lower surface humidifying part 100b as the second surface humidifying part for humidifying the lower surface which is the back surface and the second surface of the surface, the squeezing rolls 140a and 140b, the water storage tanks 150a and 150b, the blower fans 160a and 160b, and the conveying roll 170 , 171.

  The upper surface humidifying unit 100a includes a humidifying roll 110a, an intermediate roll 120a that rotates while contacting the humidifying roll 110a, and a water supply roll 130a that rotates while contacting the intermediate roll 120a. The lower surface humidification unit 100b includes a humidification roll 110b, an intermediate roll 120b that rotates while contacting the humidification roll 110b, and a water supply roll 130b that rotates while contacting the intermediate roll 120b. The humidifying rolls 110a and 110b and the water supply rolls 130a and 130b are made of nitrile rubber or the like, and the intermediate rolls 120a and 120b are made of metal such as stainless steel.

  The upper surface humidification part 100a and the lower surface humidification part 100b are formed by the same structure as shown in FIG. That is, the humidifying roll 110a and the humidifying roll 110b, the intermediate roll 120a and the intermediate roll 120b, and the water supply roll 130a and the water supply roll 130b are formed of the same member.

  The humidifying roll 110a is disposed above the paper P that is transported horizontally by the transport roll 170. The humidifying roll 110a supplies an amount of moisture necessary for humidifying the upper surface of the paper P in the horizontal state, for example, an amount of moisture W1 necessary for supplementing the moisture of the paper that has been evaporated by heating in the image forming apparatus 1A. Humidify the top surface.

  That is, the water supply roll 130a supplies water W1 in an amount necessary for humidifying the upper surface of the paper P from the water storage tank 150a. The intermediate roll 120a contacts the water supply roll 130a to obtain the moisture W1. Then, the humidifying roll 110a contacts the intermediate roll 120a while obtaining the paper P horizontally and obtains moisture W1, and humidifies the moisture W1 on the upper surface of the paper P.

  On the other hand, the humidification roll 110b is disposed below the paper P conveyed horizontally by the conveyance roll 170. The humidifying roll 110b has an amount of moisture W2 necessary to make up the amount of moisture necessary for humidifying the lower surface of the paper P in the horizontal state, for example, moisture of the paper that has been evaporated by heating in the image forming apparatus 1A. Is humidified on the lower surface.

  That is, the water supply roll 130b supplies the water W2 in an amount necessary for humidifying the lower surface of the paper P from the water storage tank 150b. The intermediate roll 120b is in contact with the water supply roll 130b to obtain moisture W2. Then, the humidifying roll 110b contacts the intermediate roll 120b to obtain moisture W2 while conveying the paper P horizontally, and humidifies the moisture W2 on the lower surface of the paper P. In the embodiment, the upper surface humidifying unit 100a and the lower surface humidifying unit 100b are configured such that the moisture W1 and the moisture W2 have the same amount at the moisture humidification positions on the upper surface and the lower surface. A specific configuration will be described later.

A squeeze roll 140a, which is a roll member, for example, as a member that restricts the amount of water supply, is disposed above the paper P, and becomes water W1 by scraping excess water from the surface of the water supply roll 130a. In addition, a squeeze roll 140b, which is a roll member, for example, as a member for limiting the amount of water supply, is disposed below the paper P, and becomes water W2 by scraping excess water from the surface of the water supply roll 130b. Yes.
In the present embodiment, the squeeze rolls 140a and 140b are arranged, but other members may be used as long as excessive water can be removed from the surfaces of the water supply roll 130a and the water supply roll 130b. For example, a blade-like member that forms a minute gap between the plate-like member and the water supply roll may be used.

  The water storage tank 150a is disposed above the paper P, and stores water W so that the water supply roll 130a is immersed to supply water W1. Moreover, the water tank 150b is arrange | positioned under the paper P, and the water | moisture content W is stored so that the water supply roll 130b may immerse and supply the water | moisture content W2.

  The blower fans 160a and 160b are for simultaneously blowing air to the upper and lower surfaces of the paper P to remove excess moisture such as the paper P humidified by the humidifying rolls 110a and 110b. The transport roll 170 transports the paper P discharged from the image forming apparatus main body 1A horizontally and is humidified by the humidifying rolls 110a and 110b. In the conveyance roll 171, the paper P humidified by the humidification rolls 110a and 110b is conveyed and discharged to the bookbinding apparatus 1C.

  Next, the geometric relationship of the structure which concerns on the upper surface humidification part 100a and the lower surface humidification part 100b of embodiment is demonstrated using FIG. 4, r1 is the radius of the humidifying rolls 110a and 110b, r2 is the radius of the intermediate rolls 120a and 120b, and r3 is the radius of the water supply rolls 130a and 130b.

  Further, in the upper surface humidifying unit 100a shown in FIG. 4, θ1a (radian) is the central angle in the rotation direction until the humidifying roll 110a contacts the intermediate roll 120a to obtain the moisture W1 and humidifies the upper surface. , Θ2a (radian) is the central angle in the rotational direction until the intermediate roll 120a comes into contact with the water supply roll 130a to obtain moisture and comes into contact with the humidifying roll 110a, and θ3a (radian) is the water supply roll 130a. This is the central angle in the rotational direction from when the water W1 is supplied from the water storage tank 150a to when it comes into contact with the intermediate roll 120a.

  In addition, in the lower surface humidifying unit 100b shown in FIG. 4, θ1b (radian) is the central angle in the rotation direction until the humidifying roll 110b comes into contact with the intermediate roll 120b to obtain the moisture W2 and humidifies the upper surface. , Θ2b (radian) is the central angle in the rotational direction until the intermediate roll 120b comes into contact with the water supply roll 130b to obtain moisture and comes into contact with the humidification roll 110b, and θ3b (radian) is the water supply roll 130b. This is the central angle in the rotation direction from when the water W2 is supplied from the water storage tank 150b to when it comes into contact with the intermediate roll 120b.

  In the upper surface humidifying unit 100a, the first distance traced by the water W1 from the position SP1 where the water supply roll 130a supplies the water W1 from the water storage tank 150a to the position KP1 where the humidification roll 110a humidifies the water W1 on the upper surface of the paper P. The distance L1 is as follows: 2 × r1 × θ1a + 2 × r2 × θ2a + 2 × r3 × θ3a.

  In the lower surface humidification unit 100b, the second distance traced by the water W2 from the position SP2 where the water supply roll 130b supplies the water W2 from the water storage tank 150b to the position KP2 where the humidification roll 110a humidifies the water W2 on the upper surface of the paper. The distance L2 is 2 × r1 × θ1b + 2 × r2 × θ2b + 2 × r3 × θ3b. The sheet humidifying device 1B is configured such that the ratio between the distance L1 and the distance L2 falls within a predetermined range, and a specific example of the embodiment will be described below.

  In the embodiment, the condition is that θ2a + θ2b = 2 × π, θ1a−θ2a + θ3a = 2 × π, and θ1b−θ2b + θ3b = π. In other words, as described above, the intermediate roll 120a and the intermediate roll 120b have the same configuration, and the surface areas for transporting the water W1 and the water W2 are upside down, and the relationship is θ2a + θ2b = 2 × π.

  Moreover, in the upper surface humidification part 100a, the phase from the position KP1 to the position SP1 is 2 × π (radian), the humidification roll 110a is counterclockwise, the intermediate roll 120a is clockwise, and the water supply roll 130a is counterclockwise. Therefore, the relationship is θ1a−θ2a + θ3a = 2 × π. Further, in the lower surface humidifying unit 100b, the phase from the position KP2 to the position SP2 is π (radian), the humidifying roll 110b is clockwise, the intermediate roll 120b is counterclockwise, and the water supply roll 130b is clockwise. The relation is θ1b−θ2b + θ3b = π.

  When these relationships are substituted into the distance L1 and the distance L2, the distance L1 is 2 × (r1 × θ1a + r2 × θ2a + r3 × (4 × π−θ2b−θ1a)), and the distance L2 is 2 × (r1 × θ1b + r2). × θ2b + r3 × (π−θ1b + θ2b)). In the sheet humidifying apparatus 1B according to the embodiment, r1, r2, r3, θ1a, θ2a, and θ2b are determined so as to satisfy the following expressions, whereby the range of the ratio between the distance L1 and the distance L2 is determined. It is determined.

Furthermore, it is desirable that a space S of a portion surrounded by three rolls of the water supply roll 130a, the intermediate roll 120a, and the humidifying roll 110a is secured. That is, when the intermediate roll 120a comes into contact with the water supply roll 130a to obtain moisture and comes into contact with the humidifying roll 110a, the central angle θ2a in the rotation direction is about 3 / 4π (135 degrees), and the water storage of the upper surface humidifying unit 100a It becomes easy to form the depth of the tank 150a.
In addition, in order to form the depth of the water storage tank 150a of the upper surface humidifying unit 100a, the radius r3 of the water supply roll 130a is preferably the same as or slightly larger than the radius r2 of the intermediate roll 120a. Further, the radius r1 of the humidifying roll 110a is the same as or slightly larger than the radius r2 of the intermediate roll 120a, so that the water supply roll 130a can be separated from the paper conveyance path, and the depth of the water storage tank 150a can be easily formed.
The above is a description of the case where the water supply roll 130a of the upper surface humidifying unit 100a is arranged on the downstream side in the transport direction of the humidifying roll 110a. This is shown in FIG. However, in this case, since there is no space on the water supply roll 130a of the upper surface humidification unit 100a, there is a disadvantage that the squeeze roll 140a cannot be disposed.
In the embodiment of FIG. 7, the condition is that θ2a + θ2b = 2 × π, θ1a−θ2a + θ3a = 0, and θ1b−θ2b + θ3b = π. In other words, as described above, the intermediate roll 120a and the intermediate roll 120b have the same configuration, and the surface areas for transporting the water W1 and the water W2 are upside down, and the relationship is θ2a + θ2b = 2 × π.
Further, in the upper surface humidifying unit 100a, the phase from the position KP1 to the position SP1 is 0 (radian), the humidifying roll 110a is counterclockwise, the intermediate roll 120a is clockwise, and the water supply roll 130a is counterclockwise. , Θ1a−θ2a + θ3a = 0 (radian). Further, in the lower surface humidifying unit 100b, the phase from the position KP2 to the position SP2 is π (radian), the humidifying roll 110b is clockwise, the intermediate roll 120b is counterclockwise, and the water supply roll 130b is clockwise. The relation is θ1b−θ2b + θ3b = π.
When these relationships are substituted into the distance L1 and the distance L2, the distance L1 is 2 × (r1 × θ1a + r2 × θ2a + r3 × (2 × π−θ2b−θ1a)), and the distance L2 is 2 × (r1 × θ1b + r2). × θ2b + r3 × (π−θ1b + θ2b)). In the sheet humidifying apparatus 1B according to the embodiment, r1, r2, r3, θ1a, θ2a, and θ2b are determined so as to satisfy the following expressions, whereby the range of the ratio between the distance L1 and the distance L2 is determined. It is determined.

  Next, an example of the embodiment will be described with reference to FIG. As shown in FIG. 5, r1, r2, and r3 shown in FIG. 4 are the same. In other words, the humidifying rolls 110a and 110b, the intermediate rolls 120a and 120b, and the water supply rolls 130a and 130b have the same radius r.

  Also, θ2a is 3 / 4π (135 degrees), and θ2b is 5 / 4π (225 degrees). With such a configuration, the distance L1 is r × 7 / 2π, and the distance L2 is also r × 7 / 2π.

  In such an example where the distance L1 and the distance L2 are the same, when the water W1 supplied at the position SP1 of the water supply roll 130a reaches the position KP1 of the humidifying roll 110a and simultaneously with the water supply of the water W1, the water supply roll The time when the water W2 supplied at the position SP2 of 130b reaches the position KP2 of the humidifying roll 110b is the same.

  According to the sheet humidifying apparatus 1B of the embodiment, the upper surface humidifying unit 110a that is the same component configuration and the lower side of the upper and lower surfaces of the sheet P transported horizontally with the simple configuration as described above. The moisture W1 and W2 that are the same amount of humidification are humidified from the humidification chamber 110b.

Further, according to the paper humidifying device 1B, the distance from the supply of the water W1 and W2 to the start of humidification with respect to the front and back of the paper P is substantially the same, and the start of humidification is substantially the same on the front and back of the paper P. Thus, the efficiency of the humidification process can be improved. In particular, in the configuration shown as an example, the start of humidification is the same on both sides of the paper P.
The above is a description of the case where the water supply roll 130a of the upper surface humidifying unit 100a is arranged on the downstream side in the conveyance direction of the humidification roll 110a, but the water supply roll 130a of the upper surface humidification unit 100a is arranged upstream of the conveyance direction of the humidification roll 110a. In other words, as an example of the embodiment shown in the second schematic diagram of FIG. 7, θ2a is 5 / 4π (225 degrees), and θ2b is 3 / 4π (135 degrees). With such a configuration, the distance L1 is r × 5 / 2π, and the distance L2 is also r × 5 / 2π. When the water supply roll 130a of the upper surface humidification unit 100a is arranged upstream in the conveyance direction of the humidification roll 110a, compared to the case where the water supply roll 130a of the upper surface humidification unit 100a is arranged downstream in the conveyance direction of the humidification roll 110a. Thus, there is an advantage that the distance from the supply of moisture W1, W2 to the start of humidification on the front and back sides of the paper P is short, that is, the time until the start of humidification can be shortened, but on the water supply roll 130a of the upper surface humidification unit 100a. There is a disadvantage in that the squeezing roll 140a cannot be disposed because there is no space in the space.

  Next, the bookbinding apparatus 1C of the embodiment will be described. FIG. 6 is a schematic configuration diagram of the bookbinding apparatus 1C. A bookbinding apparatus 1C illustrated in FIG. 6 includes a paper introduction unit 210 that introduces the paper P into the bookbinding apparatus 1C, a paper discharge unit 220 that discharges the paper P without binding, and a paper bundle storage unit that uses the paper P as a paper bundle. 230, a sheet bundle conveying unit 240 that conveys a sheet bundle, a glue applying unit 250 that applies glue to the sheet bundle, a cover supply unit 260 that accommodates a cover that is sheathed on the sheet bundle, and a cover sheet is cut to a predetermined length. A plurality of sheets P conveyed from the sheet humidifying device 1B, including a cover cutting section 270 for covering, a cover exterior section 280 for covering the cover in a bundle of sheets to form a booklet (case binding), and a booklet accommodating section 290 for accommodating the booklet. Bookbinding.

  The paper P supplied from the paper humidifier 1B is introduced into the paper introduction unit 210. In the paper introduction unit 210, the paper P is transported by the inlet rolls 211 and 212, and is branched to the paper discharge unit 220 or the paper bundle storage unit 230 by the transport path switching unit 213.

  In the paper discharge unit 220, the paper P is branched and transported by the transport rolls 221 and 222, and is discharged and stored on the fixed paper discharge tray 224 by the paper discharge roll 223. As described above, the paper discharge unit 220 discharges the paper P without bookbinding.

  In the sheet bundle storage unit 230, the paper P branched to the downstream side in the paper transport direction by the transport path switching unit 213 is guided to the transport rolls 232, 233, 234, 235, 236 and is transported and stored. In the sheet bundle storage unit 230, the sheets P stored on the inclined sheet bundle mounting table 237 are sequentially stacked on the sheet bundle mounting table 237 to form a sheet bundle. Further, the sheet bundle storage unit 230 includes a sheet rear end positioning member 238 and a sheet width alignment member 239 that positions the sheet width direction. By moving the sheet trailing edge positioning member 238 and the sheet width aligning member 239, the sheets P are stacked on the sheet bundle mounting table 237 with the ends aligned.

  In the sheet bundle conveying unit 240, the sheet bundle loaded in the sheet bundle accommodating unit 230 is conveyed obliquely downward. The sheet bundle is held by the holding unit 241 and is disposed so as to be turned so that the surface on which the paste application process is performed is on the lower side.

  The glue application unit 250 applies an adhesive roll 251 for applying glue to a sheet bundle, a drive motor 252 that rotates and moves the application roll 251, an adhesive container 253 that contains adhesive, and an adhesive container while supporting the adhesive container 253. A paste container mounting table 254 for moving 253 to the retracted position and the paste application position is provided. The glue application unit 250 applies glue to the sheet bundle as the glue container mounting table 254 moves from the retracted position to the glue application position. The glue container 253 supported by the glue container mounting table 254 moves, and the application roll 251 moves while being rotated by the drive motor 252 while being immersed in the glue container 253.

  In the cover sheet supply unit 260, a cover sheet for case binding a bundle of sheets is stored in the cover sheet storage unit 261. The cover sheets are separated one by one by a paper feed roll 262 and conveyed to a cover sheet cutting unit 270 by conveyance rolls 263 and 264.

  The cover cutting unit 270 adjusts the length of the cover by cutting the length of the cover in the conveyance direction. The cover conveyance direction corresponds to the width direction of the cover after case binding. The cover sheet cutting unit 270 is, for example, a roll cutter unit including a rotary blade and a fixed blade. The rotary blade rotates while contacting the fixed blade, and cuts the cover sheet.

  In the cover cover exterior part 280, the cover sheet cut by the cover sheet cutting part 270 is introduced by the transport roll 265. The cover introduced into the cover exterior portion 280 is conveyed along the guide plate 281 and stopped. The sheet bundle on which the glue is applied by the glue applying unit 250 is placed at the center of the cover. Then, the cover is folded by the first bending member 282A, the second bending member 282B, and the pressure member 283, and the sheet bundle is bound into a booklet.

  The booklet storage unit 290 stores booklets bound and bound by the cover outer cover 280. In the booklet storage unit 290, the booklets are placed on the booklet placement table 291 and sequentially stacked.

  The above is the description of the image forming apparatus 1 of the embodiment. As described above, the moisture content of the paper P decreases before and after passing through the image forming apparatus main body 1A. That is, in the image forming apparatus main body 1A, heat is applied to the paper P by the fixing unit 60, and moisture contained in the paper P is evaporated at this time. As a result, the paper P shrinks and the dimensions are reduced.

  For example, the moisture content of the paper P is normally 5 wt% to 6 wt% before passing through the image forming apparatus main body 1A for plain paper, but becomes about 3 wt% after passing through the image forming apparatus main body 1A. In the paper P, there is a case where the shrinkage of about 0.15% in the fiber direction and about 0.3% in the direction orthogonal to the fiber direction may occur.

  In a booklet bound using such a contracted paper P, there is a difference in water content between the peripheral portion and the central portion, which may cause undulation. According to the image forming apparatus 1 of the embodiment, by using the paper humidifying device 1B, the front and back of the paper P are evenly humidified, the influence of moisture evaporation of the bound booklet is suppressed, and the quality of the booklet is maintained. Improvement can be achieved.

The above is the description of the sheet humidifying device 1B and the image forming apparatus 1 of the embodiment, but the present invention is not limited to the above-described embodiment.
For example, the paper transport direction in the paper humidifying device 1B is not limited to the horizontal direction, but may be a slightly oblique horizontal direction.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 1A Image forming apparatus main body 1B Paper humidification apparatus 1C Bookbinding apparatus 2 Control part 3K-3C (3) Image formation part 10K-10C (10) Photoconductor 20K-20C (20) Charging part 30K-30C (30) Exposure unit 40K to 40C (40) Development unit 41K to 41C (41) Development roll 50 Transfer unit 51 Intermediate transfer belt 52 Backup roll 53 Support rolls 54K to 54C (54) Primary transfer roll 55 Secondary transfer roll 60 Fixing unit 61 Heating roll 62 Pressure rolls 70K to 70C (70) Cleaning unit 80 Paper storage unit 90 Paper feed roll 91 Transport roll 100a Upper surface humidification unit 100b Lower surface humidification unit 110a, 110b Humidification rolls 120a, 120b Intermediate rolls 130a, 130b Water supply roll 140a, 140b Squeeze rolls 150a, 150b 160a, 160b Blower fans 170, 171 Conveying roll 210 Paper introducing unit 220 Paper discharging unit 230 Paper bundle accommodating unit 240 Sheet bundle conveying unit 250 Glue applying unit 260 Cover sheet supplying unit 270 Cover sheet cutting unit 280 Cover sheet exterior unit 290 Booklet accommodating unit P Sheet W, W1, W2 Moisture r, r1, r2, r3 Radius θ1a, θ2a, θ3a, θ1b, θ2b, θ3b Center angles SP1, SP2, KP1, KP2 Positions L1, L2 Distance S Space

Claims (11)

A first surface humidifying unit having a conveyance path for conveying the paper in the horizontal direction and humidifying moisture on the first surface of the paper, and a second surface humidifying humidifying moisture on the second surface which is the back surface of the first surface. And
The first surface humidifying unit and the second surface humidifying unit are in contact with the intermediate roll while feeding the paper, a water supply roll that supplies water, an intermediate roll that comes into contact with the water supply roll, and obtains moisture. Each having the same configuration with a humidifying roll for obtaining moisture and humidifying the surface of the paper,
The first distance that moisture follows from the water supply position of the water supply roll of the first surface humidification unit to the water humidification position of the humidification roll, and the water humidification of the humidification roll from the water supply position of the water supply roll of the second surface humidification unit The sheet humidifying device, wherein the second distance followed by moisture to the position is substantially the same distance. The paper humidifier according to claim 1, wherein a ratio of the first distance followed by the moisture and the second distance followed by the moisture satisfies the following expression.
Here, r1 is the radius of the humidifying roll, r2 is the radius of the intermediate roll, r3 is the radius of the water supply roll, and θ1a and θ1b are the humidifying roll and the second surface of the first surface humidifying unit. Each of the humidifying rolls in the humidifying section represents a central angle in the rotation direction until the moisture comes into contact with the intermediate roll to obtain moisture and humidifies the first face, and θ2a and θ2b are the first face humidifying sections. The intermediate roll and the intermediate roll of the second surface humidifying unit represent the central angles in the rotational direction until they contact the water supply roll to obtain moisture and contact the humidifying roll, respectively, θ3a and θ3b are The water supply roll of the first surface humidification unit and the water supply roll of the second surface humidification unit each represent a central angle in the rotation direction until water is supplied and contact with the intermediate roll, and θ2a + θ2b = The condition is 2 × π, θ1a−θ2a + θ3a = 2 × π, and θ1b−θ2b + θ3b = π. The said 1st surface humidification part WHEREIN: The said water supply roll is arrange | positioned in the conveyance direction downstream of the said humidification roll, and the member which restrict | limits the water supply amount is arrange | positioned on the water supply roll. Or the paper humidification apparatus in any one of Claim 2.
The paper humidifier according to claim 3, wherein the member that limits the amount of water supply is a roll member. The sheet humidifying device according to any one of claims 2 to 4, wherein θ2a is 5 / 8π ≦ θ2a ≦ 7 / 8π and θ2b is 9 / 8π ≦ θ2b ≦ 11 / 8π.
Here, θ2a and θ2b are the time until the intermediate roll of the first surface humidification unit and the intermediate roll of the second surface humidification unit contact the water supply roll to obtain moisture and contact the humidification roll. Each represents the central angle in the rotation direction. The paper humidifier according to claim 1, wherein a ratio of the first distance followed by the moisture and the second distance followed by the moisture satisfies the following expression.
Here, r1 is the radius of the humidifying roll, r2 is the radius of the intermediate roll, r3 is the radius of the water supply roll, and θ1a and θ1b are the humidifying roll and the second surface of the first surface humidifying unit. Each of the humidifying rolls in the humidifying section represents a central angle in the rotation direction until the moisture comes into contact with the intermediate roll to obtain moisture and humidifies the first face, and θ2a and θ2b are the first face humidifying sections. The intermediate roll and the intermediate roll of the second surface humidifying unit represent the central angles in the rotational direction until they contact the water supply roll to obtain moisture and contact the humidifying roll, respectively, θ3a and θ3b are The water supply roll of the first surface humidification unit and the water supply roll of the second surface humidification unit each represent a central angle in the rotation direction until water is supplied and contact with the intermediate roll, and θ2a + θ2b = The condition is 2 × π, θ1a−θ2a + θ3a = 0, and θ1b−θ2b + θ3b = π. The paper humidifier according to claim 6, wherein θ2a is 9 / 8π ≦ θ2a ≦ 11 / 8π, and θ2b is 5 / 8π ≦ θ2b ≦ 7 / 8π.
Here, θ2a and θ2b are the time until the intermediate roll of the first surface humidification unit and the intermediate roll of the second surface humidification unit contact the water supply roll to obtain moisture and contact the humidification roll. Each represents the central angle in the rotation direction. The paper humidifier according to claim 5 or 7, wherein the relationship between r2 and r3 is r2≤r3.
Here, r1 represents the radius of the humidifying roll, r2 represents the radius of the intermediate roll, and r3 represents the radius of the water supply roll. 9. The paper humidifier according to claim 5, wherein the relationship between r1 and r2 is r2 ≦ r1.
Here, r1 represents the radius of the humidifying roll, r2 represents the radius of the intermediate roll, and r3 represents the radius of the water supply roll. The sheet humidifying device according to any one of claims 1 to 9, wherein the humidifying roll and the water supply roll are formed of nitrile rubber, and the intermediate roll is formed of metal. An image forming apparatus main body for forming an image on paper;
The paper humidifier according to any one of claims 1 to 10, wherein the paper discharged from the image forming apparatus main body is humidified.
An image forming apparatus comprising: a bookbinding device that binds the paper humidified by the paper humidifying device.