SHEET MANUFACTURING APPARATUS

Abstract

A sheet manufacturing apparatus 1 includes an accumulation section 50 that forms a web W; a transport belt 621 that comes into contact with one surface of the web W to hold the web W and transports the web W; a suction section 200 that is provided above the transport belt 621 to cause the web W to be adsorbed to the transport belt 621; and a sheet forming section 70 that forms the sheet with the web W, in which the suction section 200 has a first duct 210, a second duct 220 provided downstream of the first duct 210 in the transport direction, and a third duct 230 provided downstream of the second duct 220 in the transport direction, and a plurality of third suction holes 239a and 239b are provided in a suction region 233 of the third duct 230, the suction region 233 includes a first region 233a and a second region 233b located downstream of the first region 233a in the transport direction, and the number of the third suction holes 239b provided in the second region 233b is smaller than the number of the third suction holes 239a provided in the first region 233a.

Claims

1. A sheet manufacturing apparatus that manufactures a sheet from a material containing a fiber, the sheet manufacturing apparatus comprising: an accumulation section that accumulates the material by an airflow to form a web; a transport belt that comes into contact with one surface of the web to hold the web and transports the web along a transport direction; a suction section that is provided above the transport belt to cause the web to be adsorbed to the transport belt by suction; and a sheet forming section that forms the sheet by pressurizing the web, wherein the suction section has a first duct, a second duct provided downstream of the first duct in the transport direction, and a third duct provided downstream of the second duct in the transport direction, and a plurality of suction holes for suctioning air are provided in a suction region of the third duct, the suction region includes a first region and a second region located downstream of the first region in the transport direction, and the number of the suction holes provided in the second region is smaller than the number of the suction holes provided in the first region.

2. The sheet manufacturing apparatus according to claim 1, further comprising: a humidification section that is provided to face the transport belt and applies moisture from another surface side of the web.

3. The sheet manufacturing apparatus according to claim 2, wherein the humidification section has a discharge port for discharging humidified air, and the second duct and the discharge port are disposed to face each other.

4. The sheet manufacturing apparatus according to claim 1, wherein the sheet forming section has pressurizing rollers that are provided downstream of the transport belt in the transport direction and pressurize the web separated from the transport belt.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] FIG. 1 is a schematic diagram illustrating a configuration of a sheet manufacturing apparatus according to an embodiment.

[0008] FIG. 2 is a schematic diagram illustrating a detailed configuration of a suction section.

[0009] FIG. 3 is a perspective view illustrating a disposition of a pipe coupled to a suction fan.

[0010] FIG. 4 is a plan view illustrating a configuration of a plate-shaped member.

[0011] FIG. 5 is a cross-sectional view taken along line V-V of FIG. 4 illustrating functions of a first region and a second region.

DESCRIPTION OF EMBODIMENTS

[0012] In the following embodiment, a sheet manufacturing apparatus 1 that regenerates waste paper or the like into a sheet by a dry type is exemplified as a sheet manufacturing apparatus of the present disclosure. Hereinafter, the sheet manufacturing apparatus 1 will be described with reference to the drawings. The sheet manufacturing apparatus of the present disclosure is not limited to the dry type, and may be a wet type. In the present specification, the dry type means that it is executed in the air, such as the atmosphere, not in a liquid.

[0013] In the following each drawing, XYZ axes are attached as orthogonal coordinate axes, a direction indicated by each arrow is a +direction, and a direction opposite to the +direction is a direction. A Z axis is a virtual axis along a vertical direction, and a +Z direction is an upward direction and a Z direction is a downward direction. The Z direction is the vertical direction. In the sheet manufacturing apparatus 1, a front in a transport direction of a material, a web, a sheet, and the like is a downstream, and a back side in the transport direction is an upstream. For convenience of illustration, a size of each member is different from an actual size.

[0014] As illustrated in FIG. 1, the sheet manufacturing apparatus 1 according to the present embodiment includes a first unit group 101, a second unit group 102, and a third unit group 103. The first unit group 101, the second unit group 102, and the third unit group 103 are supported by a frame (not illustrated). In FIG. 1, directions, in which a paper piece C, a sheet P3, a slit piece S, an unnecessary end material, and the like move, are indicated by white arrows. In the following description, an assembly of the paper pieces C composed of a plurality of paper pieces C is also simply referred to as the paper piece C.

[0015] The sheet manufacturing apparatus 1 manufactures a sheet P3 from the paper piece C which is a material containing fibers such as waste paper. In the sheet manufacturing apparatus 1, in a side view from the X direction, the first unit group 101, the third unit group 103, and the second unit group 102 are disposed from the Y direction to the +Y direction.

[0016] The paper piece C is transported from the first unit group 101 to the second unit group 102 via a pipe 21 crossing an inside of the third unit group 103. The paper piece C is defibrated or the like in the second unit group 102 to become a defibrated material which is an assembly of fibers, and a binder or the like is further added. The defibrated material is transported to the third unit group 103 via a pipe 24. The defibrated material is formed into a band-shaped sheet P1 after being formed into the web W by the third unit group 103. The band-shaped sheet P1 is cut by the first unit group 101 to form the sheet P3.

[0017] The first unit group 101 has a buffer tank 13, a fixed-amount supply section 15, a merging section 17, and a pipe 21. In the first unit group 101, the configurations thereof are disposed in this order from the upstream to the downstream. The first unit group 101 also has a first cutting section 81, a second cutting section 82, a tray 84, and a shredding section 86.

[0018] In addition, a sheet transport section 63 is disposed from the third unit group 103 to the first unit group 101. The sheet transport section 63 transports the band-shaped sheet P1, a strip-shaped sheet P2, the sheet P3, and the slit piece S. The first cutting section 81 and the second cutting section 82 cut the band-shaped sheet P1 into the sheet P3 having a predetermined shape.

[0019] Further, the first unit group 101 has a water supply tank 267. The water supply tank 267 is a water storage tank. The water supply tank 267 supplies water for humidification to each of a humidification section 265 and a humidification device 266 (to be described later) via a hose (not illustrated) or the like. The water stored in the water supply tank 267 can be pure water, tap water, or the like. The humidification device 266 is an example of the humidification device of the present disclosure.

[0020] The paper piece C is charged from a raw material charging port 11 to the buffer tank 13. The paper piece C contains fibers such as cellulose, and is, for example, shredded waste paper. The humidified air is supplied from the humidification device 266 included in the third unit group 103 to the inside of the buffer tank 13. As a result, the paper piece C is less likely to be electrically charged, and the adsorption between the paper pieces C is suppressed.

[0021] The paper piece C to be defibrated is temporarily stored in the buffer tank 13, and then is transported to the fixed-amount supply section 15 according to the operation of the sheet manufacturing apparatus 1. The sheet manufacturing apparatus 1 may include a shredder that shreds the paper pieces C or the like upstream of the buffer tank 13.

[0022] The fixed-amount supply section 15 has a weighing instrument 15a and a supply mechanism (not illustrated). The weighing instrument 15a weighs the mass of the paper piece C. The supply mechanism supplies the paper piece C weighed by the weighing instrument 15a to the downstream merging section 17. That is, the fixed-amount supply section 15 weighs the paper pieces C by the weighing instrument 15a for each predetermined mass, and supplies the paper pieces C to the downstream merging section 17 by the supply mechanism.

[0023] Any of digital and analog weighing mechanisms can be applied to the weighing instrument 15a. Specifically, an example of the weighing instrument 15a includes a physical sensor such as a load cell, a spring scale, or a balance. In the present embodiment, the load cell is used as the weighing instrument 15a. The predetermined mass of the paper piece C weighed by the weighing instrument 15a is, for example, several g to several tens of g.

[0024] A known technique such as a vibration type feeder can be applied to the supply mechanism. The supply mechanism may be a configuration included in the weighing instrument 15a.

[0025] The weighing and supply of the paper pieces C in the fixed-amount supply section 15 are batch processed. That is, the supply of the paper pieces C from the fixed-amount supply section 15 to the merging section 17 is intermittently executed. The fixed-amount supply section 15 may include a plurality of weighing instruments 15a, and the plurality of weighing instruments 15a may be operated with a time difference to improve the efficiency of weighing.

[0026] In the merging section 17, the shredded pieces of the slit pieces S, which are supplied from the shredding section 86, are merged and mixed with the paper pieces C supplied from the fixed-amount supply section 15. The slit pieces S and the shredding section 86 will be described later. The paper piece C in which the shredded pieces, which are described above, are mixed flows from the merging section 17 into the pipe 21.

[0027] The pipe 21 transports the paper pieces C from the first unit group 101 to the second unit group 102 by the airflow generated by a blower (not illustrated).

[0028] The second unit group 102 includes a defibration section 30 which is a dry-type defibration machine, a separation section 41, a pipe 23, a powder supply section 43, a mixing section 45, and a pipe 24. In the second unit group 102, the configurations thereof are disposed in this order from the upstream to the downstream. In addition, the second unit group 102 also includes a control section 5, a collection section 95, a compressor 97, a power supply section 99, a pipe 25 coupled to the separation section 41, and an airflow pipe 29.

[0029] The paper piece C transported through the pipe 21 flow into the defibration section 30. The defibration section 30 defibrates the paper piece C, which is the material containing fibers, by a dry type to generate the defibrated material containing fibers. A known defibration mechanism can be applied to the defibration section 30. In the present embodiment, a defibration mechanism including a rotary blade is used as the defibration section 30. The defibration mechanism shreds and defibrates the paper piece C with the rotary blade to generate fibers.

[0030] The paper piece C is a defibrated material containing fibers in which entangled fibers contained in the paper piece C are unraveled by the defibration section 30, and is transported to the separation section 41.

[0031] The separation section 41 separates the defibrated fibers. Specifically, the separation section 41 removes the unnecessary components, which are included in the fiber, for manufacturing the sheet P3. The separation section 41 separates relatively long fibers and relatively short fibers. Since the relatively short fibers may cause a decrease in the strength of the sheet P3, the relatively short fibers are sorted and excluded by the separation section 41. In addition, the separation section 41 also excludes impurities such as a coloring material and an additive contained in the paper piece C.

[0032] A known separation mechanism can be applied to the separation section 41. In the present embodiment, a disk-type separation mechanism provided with a separation filter is used as the separation section 41. The separation mechanism sorts and separates the relatively short fibers or the impurities passing through the separation filter, and the relatively long fibers not passing through the separation filter. The relatively long fibers are used as defibrated fibers for the material of the web W.

[0033] The air humidified by the humidification device 266 of the third unit group 103 is supplied into the inside of the separation section 41. As a result, the defibrated fibers are less likely to be electrically charged, and the adsorption between the fibers and the attachment to the separation section 41 are suppressed.

[0034] The defibrated fibers exclude the relatively short fibers or the like in the separation section 41. The defibrated fibers are transported to the mixing section 45 by the airflow generated by a blower (not illustrated) disposed at a distal end of the airflow pipe 29 via the pipe 23. Unnecessary components such as the relatively short fibers and the impurities are suctioned by a suction device (not illustrated) of the collection section 95 and discharged from the pipe 25 to the collection section 95.

[0035] The collection section 95 is provided with a filter (not illustrated). The filter filters out unnecessary components such as the relatively short fibers transported by the airflow from the pipe 25.

[0036] The compressor 97 generates compressed air. In the filter described above, clogging may occur due to fine particles or the like in the unnecessary components. The compressed air generated by the compressor 97 can be blown onto the filter to blow off adhered particles and clean the filter.

[0037] The power supply section 99 has a power supply device (not illustrated) that supplies power to the sheet manufacturing apparatus 1 and the control section 5. The power supply section 99 distributes the power supplied from the outside to each configuration of the sheet manufacturing apparatus 1.

[0038] The powder supply section 43 supplies the binder, which is a powder, to the mixing section 45. The mixing section 45 mixes the defibrated material and the binder supplied from the powder supply section 43 in the air. The binder binds the fibers to each other in a sheet forming section 70 described later. In the present embodiment, starch is applied as a binder, but a thermoplastic resin or the like may be used.

[0039] The powder supply section 43 includes a powder accommodating section and a powder transport section (not illustrated). The powder accommodating section is attachable to and detachable from a main body of the powder supply section 43. The powder accommodating section can be removed from the powder supply section 43, and the binder can be filled or transported. For the powder transport section, for example, an auger type screw or a transport mechanism using wind power is applied. The powder transport section supplies a constant amount of the binder per unit time to the mixing section 45 while transporting the binder.

[0040] The powder supplied from the powder supply section 43 to the mixing section 45 is not limited to the binder, and may be other additives such as a coloring material. In addition, the powder may be a mixture of the binder and other additives. Further, the sheet manufacturing apparatus 1 may include a plurality of powder supply sections 43.

[0041] The mixing section 45 mixes the powder with the defibrated material which is the fiber in the air. Although not illustrated, the mixing section 45 includes a flow path through which the fibers are transported and a fan. The fan of the mixing section 45 mixes the binder and the like with the defibrated material in the air while transporting the defibrated material on the downstream by the generated airflow. The defibrated material flows from the mixing section 45 to the pipe 24.

[0042] The control section 5 is electrically coupled to each configuration of the sheet manufacturing apparatus 1 and integrally controls the operation of the sheet manufacturing apparatus 1. The control section 5 includes a CPU (Central Processing Unit) and a storage section including a RAM (Random Access Memory) and a ROM (Read Only Memory) which are not illustrated. Various programs for controlling the sheet manufacturing apparatus 1 are stored in the storage section. The control section 5 may include dedicated hardware (application-specific integrated circuit: ASIC) that executes at least a part of various processes. That is, the control section 5 may be configured as a circuit including one or more processors that operate according to a computer program (software), one or more dedicated hardware circuits such as the ASIC, or a combination thereof.

[0043] The processor includes a CPU and a memory such as the RAM and the ROM. The memory stores program codes or instructions configured to cause the CPU to execute processing. A memory, that is, a computer-readable medium, includes anything accessible by a general-purpose or dedicated computer.

[0044] Although not illustrated, an exterior of the sheet manufacturing apparatus 1 is provided with an operation panel. The control section 5 is electrically coupled to the operation panel. A user of the sheet manufacturing apparatus 1 operates the sheet manufacturing apparatus 1 via the operation panel. The operation panel includes, for example, a touch panel type liquid crystal display device and a mechanical key.

[0045] The third unit group 103 accumulates and compresses the defibrated material containing the binder to form the band-shaped sheet P1. The third unit group 103 includes an accumulation section 50, a transport section 60, a suction section 200, the humidification section 265, the humidification device 266, a drainage tank 268, the sheet forming section 70, and the sheet transport section 63. In the third unit group 103, the accumulation section 50, the transport section 60, and the sheet forming section 70 are disposed in this order from the upstream to the downstream in the transport direction. The suction section 200 is disposed between the accumulation section 50 and the sheet forming section 70 together with the transport section 60.

[0046] The transport section 60 has an accumulation transport section 61 and a back surface transport section 62. The transport section 60 transports the web W formed in the accumulation section 50 to the downstream sheet forming section 70. In the transport direction of the web W, the accumulation transport section 61 is disposed upstream of the back surface transport section 62. A part of the accumulation transport section 61 downstream and a part of the back surface transport section 62 upstream face each other in the vertical direction. The humidification section 265 is disposed below the back surface transport section 62.

[0047] The accumulation section 50 accumulates the defibrated material, which is the material containing fibers, by an airflow and gravity to form the web W. The accumulation section 50 has a drum member 53, a blade member 55 installed in the drum member 53, a housing 51 that accommodates the drum member 53, and a suction device 59. The defibrated material is taken into the drum member 53 from the pipe 24.

[0048] The accumulation transport section 61 is disposed below the accumulation section 50. The accumulation transport section 61 has a mesh belt 611 and four tension rollers (not illustrated) that tension the mesh belt 611.

[0049] The suction device 59 faces the drum member 53 with the mesh belt 611 interposed therebetween in the direction along the Z axis.

[0050] The blade member 55 is located inside the drum member 53 and is rotationally driven by an electric motor (not illustrated). The drum member 53 is a half-cylindrical sieve. A mesh having a sieve function is provided on a side surface of the drum member 53 facing downward. The drum member 53 allows the particles such as the fibers of the defibrated material and the binder, which are smaller than a mesh opening size of the sieve, to pass from the inside to the outside.

[0051] The defibrated material is released to the outside of the drum member 53 while being stirred by the rotating blade member 55 in the drum member 53. The air humidified by the humidification device 266 is supplied into the drum member 53. As a result, the fibers, the binder, and the like are less likely to be electrically charged, and the adsorption between the fibers and the attachment to the drum member 53, the blade member 55, and the like are suppressed.

[0052] The suction device 59 is disposed below the drum member 53. The suction device 59 suctions the air in the housing 51 via the plurality of holes of the mesh belt 611. As a result, an airflow for accumulating the defibrated material on the mesh belt 611 is generated. The plurality of holes of the mesh belt 611 allow air to pass through, and it is difficult for the fibers, the binder, and the like contained in the defibrated material to pass through. As a result, the defibrated material released to the outside of the drum member 53 is suctioned downward together with the air. The suction device 59 is a known suction device such as a suction blower.

[0053] The defibrated material containing the binder or the like is dispersed in the air in the housing 51, and is accumulated on the surface above the mesh belt 611 by the gravity and the airflow generated by the suction device 59 to form the web W.

[0054] The mesh belt 611 of the accumulation transport section 61 is an endless belt and is stretched over four tension rollers. The mesh belt 611 is rotated counterclockwise in FIG. 1 by rotation of the tension roller. As a result, the defibrated material is continuously accumulated on the mesh belt 611, and the web W is formed. The web W includes a relatively large amount of the air and is soft and swollen. The accumulation transport section 61 transports the formed web W to the downstream by rotating the mesh belt 611.

[0055] The back surface transport section 62 is disposed downstream of the accumulation transport section 61 and transports the web W delivered from the accumulation transport section 61. The back surface transport section 62 peels off the web W from the surface above the mesh belt 611 and transports the web W toward the sheet forming section 70. The back surface transport section 62 is disposed above the transport path of the web W, and is disposed slightly upstream of the starting point of the mesh belt 611 on a return side, that is, an end portion in the Y direction. The +Y direction of the back surface transport section 62 and the Y direction of the mesh belt 611 partially overlap each other in the vertical direction.

[0056] The back surface transport section 62 includes a transport belt 621 and four tension rollers (not illustrated). The transport belt 621 includes a plurality of holes through which air passes. The transport belt 621 comes into contact with the surface of the web W facing upward, which is one surface of the web W, to hold the web W, and transports the web W along the transport direction in the Y direction.

[0057] The transport belt 621 is stretched by the four tension rollers, and is rotated clockwise in FIG. 1 by the rotation of the tension rollers. The suction section 200 is disposed inside the transport belt 621 stretched over the four tension rollers. The transport belt 621 holds the web W by the suction force generated by the suction section 200.

[0058] The suction section 200 causes the upper surface of the web W, which is the back surface of the web W, to be adsorbed to the transport belt 621 by the suction via the plurality of holes of the transport belt 621. The transport belt 621 is adsorbed on the upper surface of the web W and transports the web W.

[0059] The suction section 200 is provided above a region of the transport belt 621 that comes into contact with the web W in the transport path of the web W in the back surface transport section 62. The suction section 200 suctions the lower air upward via the plurality of holes of the transport belt 621. As a result, the upper surface of the web W is adsorbed to the lower surface of the transport belt 621. In this state, the transport belt 621 is rotated, and the web W is adsorbed to the transport belt 621 and transported downstream. Although not illustrated, the suction section 200 has a known suction device such as a suction fan. Details of the suction section 200 will be described later.

[0060] The humidification section 265 applies moisture to the web W from the side of the surface facing the lower side, which is the other surface side of the web W, to humidify the web W. The humidification section 265 supplies a mist M as moisture from below the web W transported by the back surface transport section 62. The humidification section 265 is provided below the back surface transport section 62 so as to face the transport belt 621 and the web W transported by the transport belt 621 in the vertical direction. For the humidification section 265, a known device such as an ultrasonic humidifier can be applied.

[0061] By humidifying the web W with the mist M, the function of the starch, which is the binder contained in the web W, is promoted, and the strength of the sheet P3 is improved. Further, since the web W is humidified from below, it is difficult for the droplets derived from the mist M to fall onto the web W. Further, since the web W is humidified from the opposite side of the upper surface of the web W coming into contact with the transport belt 621, sticking of the web W to the transport belt 621 is reduced.

[0062] The web W is separated from the transport belt 621 and delivered to the sheet forming section 70 in the vicinity of the end portion of the transport belt 621 in the Y direction. In the related art, the web W may be difficult to separate in the vicinity of the end portion of the transport belt 621. The sheet manufacturing apparatus 1 of the present embodiment is configured to easily separate the web W from the transport belt 621 by the configuration of the suction section 200 described later.

[0063] The sheet forming section 70 pressurizes and compresses the web W to form the band-shaped sheet P1. The sheet forming section 70 has a pair of a first roller 71 and a second roller 72 that are provided downstream of the transport belt 621. The sheet forming section 70 allows the web W, which is separated and sent out from the transport belt 621, to pass between the first roller 71 and the second roller 72 to be pressurized, and forms the web W into the band-shaped sheet P1. The first roller 71 and the second roller 72 are examples of the pressurizing roller of the present disclosure.

[0064] Each of the first roller 71 and the second roller 72 is a substantially cylindrical member. A rotation shaft of the first roller 71 and a rotation shaft of the second roller 72 are along the X axis. The first roller 71 is disposed substantially below the transport path of the web W, and the second roller 72 is disposed substantially above the transport path of the web W. The first roller 71 and the second roller 72 rotate close to each other while the band-shaped sheet P1 is formed from the web W.

[0065] In the direction along the X axis, a length of the first roller 71 and a length of the second roller 72 are longer than a length of the web W, that is, a width of the web W. Therefore, the web W is reliably nipped between the first roller 71 and the second roller 72.

[0066] A diameter of the first roller 71 is larger than a diameter of the second roller 72. For example, the diameter of the first roller 71 is 110 mm or more and 150 mm or less, and the diameter of the second roller 72 is 80 mm or more and 110 mm or less.

[0067] The first roller 71 includes, for example, a core metal and a surface layer that covers the core metal. An example of the core metal includes a hollow structure made of aluminum, iron, stainless steel, or the like. Examples of the material of the surface layer include fluororesins such as polytetrafluoroethylene (PTFE), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), and tetrafluoroethylene-ethylene copolymer (ETFE), a silicone resin, and the like. As a result, the releasability of the first roller 71 with respect to the web W is improved. In addition, wear and damage of the core metal are suppressed.

[0068] The second roller 72 includes, for example, a core metal, an intermediate layer, and a surface layer. An example of the core metal includes a hollow structure made of aluminum, iron, stainless steel, or the like. The intermediate layer covers the core metal and is covered with the surface layer. In other words, the intermediate layer is interposed between the core metal and the surface layer.

[0069] An example of the material of the intermediate layer includes an elastic body such as silicone rubber and urethane rubber. The hardness of the elastic body described above is preferably 30 or more and 70 or less, and more preferably 40 or more and 60 or less in a measured value by an Asker C hardness meter. The thickness of the intermediate layer is preferably 1 mm or more and 10 mm or less, and more preferably 1 mm or more and 5 mm or less.

[0070] Examples of the material of the surface layer include fluororesins such as polytetrafluoroethylene (PTFE), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), and tetrafluoroethylene-ethylene copolymer (ETFE).

[0071] Since the second roller 72 has the above-described configuration, the releasability of the second roller 72 with respect to the web W is improved. In addition, wear and damage of the intermediate layer are suppressed.

[0072] The web W is pressurized while passing between the first roller 71 and the second roller 72. The pressure applied to the web W by the first roller 71 and the second roller 72 is preferably 0.1 MPa or more and 15.0 MPa or less, more preferably 0.2 MPa or more and 10.0 MPa or less, and still more preferably 0.4 MPa or more and 8.0 MPa or less. As a result, the deterioration of the fibers in the web W is suppressed.

[0073] The first roller 71 has a function of increasing the temperature of the roller surface by incorporating an electric heater. The second roller 72 preferably also has a function of increasing the temperature of the roller surface by the electric heater in the same manner as the first roller 71.

[0074] The surface temperature of the first roller 71, that is, the temperature of the surface layer of the first roller 71 coming into contact with the web W is preferably 100 C. or higher and 130 C. or lower. The surface temperature of the second roller 72, that is, the temperature of the surface layer of the second roller 72 coming into contact with the web W is preferably 80 C. or higher and 100 C. or lower.

[0075] The first roller 71 is driven by a stepping motor (not illustrated) and rotates counterclockwise when viewed from the X direction. The second roller 72 is a driven roller that is not driven by an electric motor or the like and is driven in conjunction with the rotation of the first roller 71. Therefore, the second roller 72 rotates clockwise when viewed from the X direction.

[0076] The web W is sent out to the downstream while being nipped between the first roller 71 and the second roller 72, and heated and pressurized. That is, the web W continuously passes through the sheet forming section 70 and is press-molded while being heated. By using the first roller 71 and the second roller 72 as a pair of forming members, the web W is efficiently heated and pressurized as compared with a case where, for example, a batch type press device is used.

[0077] The web W passes through the sheet forming section 70, so that the air content is reduced and the density is increased from a relatively soft state containing a large amount of air. The fibers are bound to each other by the binder and are formed into the band-shaped sheet P1. The band-shaped sheet P1 is transported to the first unit group 101 by a plurality of rollers (not illustrated) of the sheet transport section 63.

[0078] The humidification device 266 is disposed below the humidification section 265. The humidification device 266 supplies air humidified via a plurality of pipes (not illustrated) and humidifies the above-described region of the sheet manufacturing apparatus 1. A known vaporization type humidification device can be applied to the humidification device 266. An example of the vaporization type humidification device includes a device that vaporizes moisture by blowing the air onto a wet nonwoven fabric or the like to generate humidified air.

[0079] The drainage tank 268 is a drainage tank. The drainage tank 268 is used for the humidification section 265, the humidification device 266, and the like, and collects and stores the old water. The drainage tank 268 can be removed from the sheet manufacturing apparatus 1 as necessary and can discard the accumulated water.

[0080] The band-shaped sheet P1 transported from the sheet forming section 70 to the first unit group 101 reaches the first cutting section 81. The first cutting section 81 cuts the band-shaped sheet P1 in a direction intersecting the transport direction, for example, in a direction along the X axis. The band-shaped sheet P1 is cut into the strip-shaped sheet P2 by the first cutting section 81. The strip-shaped sheet P2 is transported from the first cutting section 81 to the second cutting section 82 by the sheet transport section 63.

[0081] The second cutting section 82 cuts the strip-shaped sheet P2 in the transport direction, for example, in a direction along the Y axis. Specifically, the second cutting section 82 cuts both end portions in the direction along the X axis in the strip-shaped sheet P2. As a result, the strip-shaped sheet P2 is formed of the sheet P3 having a predetermined shape such as A4 size or A3 size.

[0082] When the strip-shaped sheet P2 is cut into the sheet P3 by the second cutting section 82, the slit pieces S, which are end materials, are generated. The slit pieces S are transported in the substantially Y direction to reach the shredding section 86 which is a shredder. The shredding section 86 shreds the slit pieces S and supplies the slit pieces S to the merging section 17 as shredded pieces. A mechanism for weighing the shredded pieces of the slit pieces S and supplying the shredded pieces to the merging section 17 may be installed between the shredding section 86 and the merging section 17.

[0083] The sheet P3 is transported substantially upward and is accumulated on the tray 84. As described above, the sheet P3 is manufactured by the sheet manufacturing apparatus 1. The sheet P3 can be applied as an alternative to, for example, copy paper or the like.

[0084] As illustrated in FIG. 2, the suction section 200 includes a first duct 210, a second duct 220, and a third duct 230. The first duct 210, the second duct 220, and the third duct 230 are disposed in this order in the Y direction which is the transport direction of the web W. That is, the second duct 220 is provided downstream in the transport direction with respect to the first duct 210, and the third duct 230 is provided downstream in the transport direction with respect to the second duct 220. The second duct 220 has a shape that is higher in the +Z direction than the first duct 210 and the third duct 230.

[0085] Although not illustrated, the suction section 200 has three suction fans. One suction fan is coupled to each of the first duct 210, the second duct 220, and the third duct 230. The first duct 210 includes a suction chamber 211 in which a negative pressure is generated by the suction fan. The second duct 220 includes a suction chamber 221 in which a negative pressure is generated by the suction fan. The third duct 230 includes a suction chamber 231 in which a negative pressure is generated by the suction fan. A known mechanism can be applied to the above-described suction fan.

[0086] The plate-shaped member 240 is disposed in a region corresponding to the lower surface of the suction chambers 211, 221, and 231. The plate-shaped member 240 is substantially plate-shaped when viewed from the Z direction, and the main surface is disposed along the XY plane. The plate-shaped member 240 includes a plurality of suction holes to be described later, and separates the inside and the outside of the suction chambers 211, 221, and 231 in a region other than the suction holes. The first duct 210, the second duct 220, and the third duct 230 suction air via a plurality of suction holes of the plate-shaped member 240. The plate-shaped member 240 is, for example, a punching metal made of aluminum.

[0087] In the plate-shaped member 240, a region corresponding to a lower surface of the suction chamber 211 is a suction region 213 of the first duct 210, a region corresponding to a lower surface of the suction chamber 221 is a suction region 223 of the second duct 220, and a region corresponding to a lower surface of the suction chamber 231 is a suction region 233 of the third duct 230.

[0088] The transport belt 621 is stretched over four tension rollers 623. The suction section 200 is disposed along a region corresponding to a lower bottom of a trapezoid on the inside of the transport belt 621 stretched substantially in a trapezoid shape when viewed from the X direction. The transport belt 621 and the plate-shaped member 240 are disposed to be separated from each other. The plate-shaped member 240 and the suction regions 213, 223, and 233 face the transport belt 621 in the vertical direction.

[0089] The suction section 200 suctions the air below the transport belt 621 via the transport belt 621. As a result, the upper surface of the web W (not illustrated) is adsorbed to the lower surface of the transport belt 621. The suction region 233 of the third duct 230 is located most downstream in the transport direction in a region where the transport belt 621 adsorbs and holds the web W.

[0090] The humidification section 265 has a discharge port 265a. The humidification section 265 discharges the humidified air containing the mist M upward. The discharge port 265a and the second duct 220 are disposed to face each other. That is, the discharge port 265a faces the suction region 223 of the plate-shaped member 240 in the vertical direction. In a transmitted view from above, the suction region 223 and the discharge port 265a have substantially the same shape.

[0091] The web W has a relatively large number of gaps inside and has a relatively sparse internal structure. Therefore, the second duct 220 adsorbs the web W to the transport belt 621 and also suctions the humidified air discharged from the humidification section 265 via the web W. Since the humidified air is suctioned by the second duct 220, the web W can be efficiently humidified. The humidified air applies moisture to the web W, and a part of the humidified air reaches the suction chamber 221 of the second duct 220.

[0092] As illustrated in FIG. 3, the suction section 200 includes pipes 215, 225, and 235. Each of the pipes 215, 225, and 235 is a tubular member bent in a substantially L-shape when viewed from the +Y direction, and a cross section substantially orthogonal to the moving direction of the airflow flowing inside is substantially circular. One end portion of each of the pipes 215, 225, and 235 is coupled to a suction fan (not illustrated) individually corresponding to each of the pipes 215, 225, and 235. In FIG. 3, the illustration on a suction fan side is omitted in each of the pipes 215, 225, and 235.

[0093] The other end portion of the pipe 215 is communicatively coupled to the side surface of the suction chamber 211 in the X direction. The other end portion of the pipe 225 is communicatively coupled to the upper side of the side surface of the suction chamber 221 in the X direction. The other end portion of the pipe 235 is communicatively coupled to the side surface of the suction chamber 231 in the X direction. Each of the suction chambers 211, 221, and 231 is suctioned from the side surface in the X direction by the corresponding suction fan.

[0094] As illustrated in FIG. 4, the plate-shaped member 240 is substantially rectangular when viewed from the Z direction, and a long side thereof is along the X axis. The transport direction of the web W (not illustrated) with respect to the plate-shaped member 240 is the Y direction. In the following description of FIG. 4, a state viewed from the Z direction will be described unless otherwise specified.

[0095] The suction region 213 of the first duct 210, the suction region 223 of the second duct 220, and the suction region 233 of the third duct 230 are substantially rectangular, respectively, and the long sides thereof are along the X axis. In the plate-shaped member 240, the suction region 213, the suction region 223, and the suction region 233 are disposed side by side in this order in the transport direction of the web W.

[0096] Partition walls 241, 243, 244, and 245 are attached to the plate-shaped member 240. Each of the partition walls 241, 243, 244, and 245 partitions the plate-shaped member 240. Each of the partition walls 241, 243, 244, and 245 is an elongated member along the X axis, and a length along the X axis is substantially equal to the length of the suction regions 213, 223, and 233. Each of the partition walls 241, 243, 244, and 245 is formed of, for example, a material such as resin.

[0097] The partition wall 241 is disposed adjacent to the long side upstream in the transport direction of the web W in the suction region 213. The partition wall 243 is disposed between the suction region 213 and the suction region 223. The partition wall 244 is disposed between the suction region 223 and the suction region 233. The partition wall 245 is disposed adjacent to the long side downstream in the transport direction of the web W in the suction region 233.

[0098] The suction region 233 of the third duct 230 includes a first region 233a and a second region 233b. The first region 233a and the second region 233b are virtual regions that divide the suction region 233 into two by the denseness and sparseness of the third suction holes 239a and 239b to be described later. The boundary between the first region 233a and the second region 233b is along the X axis. Each of the first region 233a and the second region 233b is a substantially rectangular shape in which the long side is along the X axis. An area of the first region 233a and an area of the second region 233b are substantially equal.

[0099] The second region 233b is located downstream of the first region 233a in the transport direction. That is, the second region 233b is disposed most downstream in the plate-shaped member 240. In other words, the second region 233b is located most downstream in the transport direction in a region where the transport belt 621 (not illustrated) adsorbs and holds the web W.

[0100] The suction region 213 of the first duct 210 is provided with a plurality of first suction holes 219 for suctioning air. The suction region 223 of the second duct 220 is provided with a plurality of second suction holes 229 for suctioning air. The suction region 233 of the third duct 230 is provided with a plurality of third suction holes 239a and 239b for suctioning air. The third suction holes 239a and 239b are examples of the suction holes of the present disclosure.

[0101] Each of the first suction hole 219, the second suction hole 229, and the third suction holes 239a and 239b is alternately arranged in a zigzag pattern in the direction along the X axis. These disposition forms are not limited to the above-described embodiments.

[0102] The third suction hole 239a is disposed in the first region 233a, and the third suction hole 239b is disposed in the second region 233b. The number of third suction holes 239b provided in the second region 233b is smaller than the number of third suction holes 239a provided in the first region 233a. That is, the number of the regions to be disposed per unit area is smaller than in the third suction hole 239b in the third suction hole 239a. In other words, the third suction hole 239a is relatively densely provided in the first region 233a, and the third suction hole 239b is relatively sparsely provided in the second region 233b.

[0103] In the present embodiment, the number of the third suction holes 239a is set to 36, and the number of the third suction holes 239b is set to 12. In addition, the number of the third suction holes 239a and the number of the third suction holes 239b are not limited to the above-described number, in a range in which the above-described relationship between the denseness and sparseness is established.

[0104] In addition, a distance between the adjacent third suction holes 239a in the direction along the X axis is relatively narrow in the region on the +X direction side and relatively wide in the region on the X direction side. That is, in the first region 233a, the third suction holes 239a on the +X direction side are disposed relatively densely, and the third suction holes 239a on the X direction side are disposed relatively sparsely.

[0105] As described above, in the suction chamber 231 corresponding to the suction region 233, air is suctioned via the pipe 235 coupled to the side surface in the X direction. That is, the third suction holes 239a are sparsely disposed in the region close to the suction fan and are densely disposed in the region far from the suction fan. Therefore, in the suction chamber 231, the balance of the wind speed of the air to be suctioned is taken, and the variation in suction force in the plurality of third suction holes 239a is reduced. As a result, in the first region 233a, the suction force of the suction fan is relatively evenly distributed, and the web W is reliably held on the transport belt 621.

[0106] The denseness and sparseness of the disposition of the third suction holes 239a may be adjusted according to the disposition of the suction fans. Specifically, for example, in a form in which air is suctioned from the upper center of the suction region 233, the third suction holes 239a near the center are relatively sparsely disposed in the direction along the X axis, and the third suction holes 239a on the +X direction side and the X direction side are relatively densely disposed.

[0107] As illustrated in FIG. 5, the web W is adsorbed to the transport belt 621 by the suction force F1 in the first region 233a, and the web W is adsorbed to the transport belt 621 by the suction force F2 in the second region 233b. The web W is separated from the transport belt 621 in the vicinity of downstream of the second region 233b in the transport direction, and is delivered to the sheet forming section 70 (not illustrated).

[0108] As described above, in the first region 233a, the third suction holes 239a are disposed relatively densely, and in the second region 233b, the third suction holes 239b are disposed relatively sparsely. Therefore, the suction force F2 is smaller than the suction force F1. As a result, the web W is reliably held on the transport belt 621 with the suction force F1 in the first region 233a, and is held on the transport belt 621 with the suction force F2 which is relatively weak in the second region 233b.

[0109] According to the present embodiment, the following effects can be obtained.

[0110] The web W can be easily separated from the transport belt 621. Specifically, the suction region 233 of the third duct 230 is located downstream of the suction section 200, and the second region 233b is located downstream of the suction region 233. The web W moves to the downstream away from the transport belt 621 in the downstream in the vicinity of the second region 233b. Due to the denseness and sparseness of the third suction holes 239a and 239b, the suction force F2 acting on the web W in the second region 233b is smaller than the suction force F1 acting on the web W in the first region 233a. Therefore, the web W is easily separated from the transport belt 621, and the web W is smoothly delivered to the sheet forming section 70 in the downstream from the transport belt 621. Therefore, it is possible to provide the sheet manufacturing apparatus 1 that facilitates the separation of the web W.