Sheet manufacturing device

Abstract

To prevent a material for forming a sheet from adhering to a route of piping for transporting the material in a sheet manufacturing device.SOLUTION: A sheet manufacturing device 1 comprises: a defibrating part 31 for defibrating a paper piece C to obtain defibrated product including fibers; a separation part 32 for separating the fibers from the defibrated product fed from the defibrating part 31; a deposition part 50 for forming a web W by depositing the fibers; a sheet molding part 70 for molding a sheet P1 by compressing the web W; and a piping 24 for connecting the separation part 32 and the deposition part 50 and transporting the fibers from the separation part 32 to the deposition part 50. The route of the piping 24 for transporting the fibers is constituted of members having conductivity. A bent part of the route is constituted of a middle resistance member having higher surface resistivity than that of members constituting other parts of the route.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a sheet manufacturing apparatus. [Background technology]

[0002] Patent Document 1 discloses a sheet manufacturing apparatus including a defibrating unit, a separating device, a web forming unit, and a sheet forming unit. The defibrating unit defibrates raw materials containing fibers. The separating device removes foreign matter from the defibrated material defibrated by the defibrating unit. The web forming unit forms a web by stacking the defibrated material from which foreign matter has been removed by the separating device. The sheet forming unit forms a sheet from the web formed by the web forming unit. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-121294 Summary of the Invention [Problem to be solved by the invention]

[0004] In the sheet manufacturing apparatus of Patent Document 1, the defibrated material from which foreign matter has been removed in the separation device is transported by airflow through a pipe connecting the separation device and the web forming unit toward the web forming unit. In this case, the defibrated material becomes electrically charged as it is transported by the airflow, and there is a risk that the defibrated material will adhere to the inner wall of the pipe. [Means for solving the problem]

[0005] The sheet manufacturing apparatus includes a defibrating unit that defibrates a material containing fibers to obtain defibrated material containing the fibers, a separation unit that separates the fibers from the defibrated material supplied from the defibrating unit, a deposition unit that deposits the fibers to form a web, a sheet forming unit that compresses the web to form a sheet, and piping that connects the separation unit and the deposition unit and transports the fibers from the separation unit to the deposition unit, wherein the path in the piping along which the fibers are transported is made of a conductive material, and the bent portion of the path is made of a medium-resistivity material that has a higher surface resistivity than the materials that form the other parts of the path. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 1 is a schematic diagram illustrating a configuration of a sheet manufacturing apparatus according to an embodiment. [Figure 2] FIG. 3 is a schematic diagram showing the configuration of a pipe connecting a separation unit and a deposition unit. DETAILED DESCRIPTION OF THE INVENTION

[0007] In the following embodiments, a sheet manufacturing apparatus 1 that recycles fibrous materials such as waste paper into sheets in a dry process is exemplified as the sheet manufacturing apparatus of the present invention. The sheet manufacturing apparatus 1 will be described below with reference to the drawings. The sheet manufacturing apparatus of the present invention is not limited to a dry process and may be a wet process. In this specification, the term "dry process" refers to a process that is carried out in air such as the atmosphere, rather than in a liquid.

[0008] In each drawing, the same components are denoted by the same reference numerals, and redundant explanations are omitted. In the present specification, the terms "same," "identical," and "simultaneous" do not only refer to being completely identical. For example, in the present specification, when the terms "same," "identical," and "simultaneous" are used, they also include cases where the components are identical taking into account measurement errors. In addition, in the present specification, when the terms "same," "identical," and "simultaneous" are used, they also include cases where the components are identical taking into account manufacturing variations.

[0009] In this specification, the terms "same," "identical," and "simultaneous" are intended to include cases where the same is true to the extent that the functionality is not impaired. For example, "the dimensions of both are the same" means that, taking into account measurement errors and manufacturing variations of components, the difference in the dimensions of both is within ±5% of one dimension, and more preferably within ±3%.

[0010] In each figure, X, Y, and Z represent three spatial axes that are orthogonal to one another. In this specification, the directions along these axes are referred to as the X-axis direction, the Y-axis direction, and the Z-axis direction. When specifying a direction, the positive direction is indicated by "+" and the negative direction by "-", and both positive and negative signs are used to indicate the direction, with the direction indicated by the arrow in each figure being the + direction and the direction opposite the arrow being the - direction.

[0011] The Z-axis direction indicates the direction of gravity, the +Z direction indicates the vertically upward direction, and the -Z direction indicates the vertically downward direction. The plane containing the X-axis and Y-axis is described as the XY plane, the plane containing the X-axis and Z-axis as the XZ plane, and the plane containing the Y-axis and Z-axis as the YZ plane. The XY plane is a horizontal plane. The three spatial axes of X, Y, and Z, which are not limited to positive and negative directions, will be described as the X-axis, Y-axis, and Z-axis.

[0012] The X-axis direction is the horizontal direction along the installation surface, which is a horizontal plane on which the sheet manufacturing apparatus 1 is installed. The Y-axis direction is the horizontal direction along the installation surface on which the sheet manufacturing apparatus 1 is installed. The Z-axis direction is the normal direction to the installation surface on which the sheet manufacturing apparatus 1 is installed, and is the height direction of the sheet manufacturing apparatus 1.

[0013] In the following description, the +Z direction may be referred to as "upward" and the -Z direction may be referred to as "downward." In the following description, in the sheet manufacturing apparatus 1, the end of the conveying direction of the raw material, web W, sheets P1, P2, P3, etc. may be referred to as "downstream," and the upstream side of the conveying direction may be referred to as "upstream." For convenience of illustration, the sizes of each component are different from the actual sizes.

[0014] 1. Embodiment 1 1, the sheet manufacturing apparatus 1 according to this 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 shown).

[0015] In Figure 1, the white arrows indicate the direction in which the paper pieces C, defibrated material containing fiber, mixture containing binder, etc., sheets P1, P2, P3, slit pieces S, and unnecessary scraps, etc. move. In the following explanation, a collection of paper pieces C made up of multiple paper pieces C will also be simply referred to as paper piece C.

[0016] The sheet manufacturing apparatus 1 manufactures a sheet P3 from pieces of paper C such as waste paper. The pieces of paper C are an example of a material containing fiber. In the sheet manufacturing apparatus 1, a first unit group 101, a third unit group 103, and a second unit group 102 are arranged from the -Y direction to the +Y direction in a side view from the -X direction.

[0017] According to the sheet manufacturing apparatus 1 of this embodiment, the sheet P3 can be manufactured from the paper scraps C, and thus the amount of waste paper scraps C can be reduced by recycling the paper scraps C. Therefore, the sheet manufacturing apparatus 1 of this embodiment can contribute to achieving the Sustainable Development Goals (SDGs) such as Goal 12 "Ensure sustainable consumption and production patterns."

[0018] The pieces of paper C are transported from the first unit group 101 to the second unit group 102 via a pipe 21 that traverses the third unit group 103. The pieces of paper C are then defibrated and turned into fibers in the second unit group 102, and then made into a mixture containing a binder and the like. The mixture is transported via a pipe 24 to the third unit group 103. The mixture is made into a web W in the third unit group 103, and then formed into a belt-shaped sheet P1. The belt-shaped sheet P1 is cut in the first unit group 101 to become a sheet P3.

[0019] The first unit group 101 includes a raw material supply device 13, a measuring unit 15, a confluence unit 17, and a pipe 21. These components are arranged in the above order from upstream to downstream in the first unit group 101. The first unit group 101 also includes a downstream transport unit 82 of the transport unit 80, a tray 191, and a shredding unit 913.

[0020] The downstream conveying unit 82 has a first cutting section 832 and a second cutting section 834. The first cutting section 832 cuts the strip-shaped sheet P1 into single sheets P2. The second cutting section 834 cuts the single sheets P2 into sheets P3 of a predetermined shape. The first cutting section 832 and the second cutting section 834 are examples of cutters.

[0021] First unit group 101 has water supply unit 67. Water supply unit 67 is a water storage tank. Water supply unit 67 supplies water for humidification to each of first humidifying unit 65 and second humidifying unit 66 (described later) via a water supply pipe (not shown).

[0022] The raw material supply device 13 stores paper pieces C, which are raw materials for the sheet P3, and supplies them downstream. The raw material supply device 13 has a raw material inlet 131, a storage section 132, and a discharge section 140.

[0023] The pieces of paper C are fed into the storage section 132 from the raw material feed port 131. The pieces of paper C include fibers such as cellulose, and are, for example, shredded waste paper. Humidified air is supplied into the storage section 132 from the second humidifier 66 provided in the third unit group 103.

[0024] The pieces of paper C are temporarily stored in the storage unit 132, and then transported to the measuring unit 15 via the discharge unit 140. The sheet manufacturing apparatus 1 may be provided with a shredder upstream of the storage unit 132 that shreds the pieces of paper C and the like.

[0025] The measuring unit 15 has a sensor unit 15a and a supply mechanism (not shown). The sensor unit 15a measures the mass of the pieces of paper C. The supply mechanism supplies the pieces of paper C weighed by the sensor unit 15a to the downstream junction 17. That is, the measuring unit 15 weighs the pieces of paper C by a predetermined mass using the sensor unit 15a, and supplies them to the downstream junction 17 using the supply mechanism.

[0026] The sensor unit 15a can be either a digital or analog weighing mechanism. Specifically, the sensor unit 15a can be a physical sensor such as a load cell, a spring balance, or a balance. In this embodiment, a load cell is used as the sensor unit 15a. The predetermined mass at which the sensor unit 15a weighs the piece of paper C is, for example, several grams to several tens of grams.

[0027] The supply mechanism may be an openable / closable feeder, etc. The supply mechanism may be included in the sensor unit 15a.

[0028] The measurement unit 15 measures and supplies the pieces of paper C in a batch process. That is, the supply of pieces of paper C from the measurement unit 15 to the junction 17 is carried out intermittently. The measurement unit 15 may have multiple combinations of sensor unit 15a and supply mechanism, and multiple sensor units 15a may be operated at staggered times to improve the efficiency of measurement and supply.

[0029] The sheet manufacturing apparatus 1 has two sensor units 15a and a supply mechanism attached to each of them, whereby pieces of paper C are conveyed to the junction 17 alternately from the two sets of sensor units 15a and supply mechanisms.

[0030] At the confluence 17, the pieces of paper C supplied from the measuring unit 15 are combined with the fine fragments of the slit pieces S supplied from the shredding unit 913 and mixed together. The slit pieces S and the shredding unit 913 will be described later. The pieces of paper C mixed with the fine fragments flow from the confluence 17 into the pipe 21.

[0031] The piping 21 transports the pieces of paper C from the first unit group 101 to the second unit group 102 by the suction airflow generated by the downstream defibrating unit 31. Humidified air is supplied to the piping 21 from the second humidifying unit 66 provided in the third unit group 103.

[0032] The second unit group 102 has a defibrating unit 31, which is a dry type defibrator, a separating unit 32, and piping 24. In the second unit group 102, these components are arranged in the above order from upstream to downstream. The second unit group 102 also has a piping 25 connected to the separating unit 32, a collecting unit 35, a compressor 38, and a power supply unit 39.

[0033] The paper pieces C transported through the piping 21 flow into the defibrating unit 31. The defibrating unit 31 dry-defibrates the paper pieces C supplied from the measuring unit 15 to obtain defibrated material containing fibers. A defibrating mechanism that uses a rotating rotor or the like can be applied to the defibrating unit 31.

[0034] The defibrating unit 31 of this embodiment defibrates the paper pieces C into fibers in a dry manner, which reduces the amount of water used and the amount of wastewater discharged compared to wet defibration methods in which defibration is performed in water. Therefore, the defibrating unit 31 of this embodiment can contribute to achieving the Sustainable Development Goals (SDGs) such as Goal 6, "Ensure availability and sustainable management of water and sanitation for all." The defibrating unit 31 of this embodiment can contribute to achieving the Sustainable Development Goals (SDGs) such as Goal 14, "Conserve and sustainably use the oceans and marine resources for sustainable development."

[0035] The defibrating unit 31 of this embodiment eliminates the need to dry the defibrated material, thereby reducing the amount of carbon dioxide generated in the process of defibrating the paper pieces C. Therefore, the defibrating unit 31 of this embodiment can contribute to achieving the Sustainable Development Goals (SDGs) such as Goal 13 "Take urgent action to combat climate change and its impacts."

[0036] The defibrating unit 31 may have the following configuration, for example. The defibrating unit 31 includes a stator and a rotor. The stator has a substantially cylindrical inner surface. The rotor is installed inside the stator and rotates along the inner surface of the stator. The small pieces of paper C are sandwiched between the inner surface of the stator and the rotor and are defibrated by the shear force generated between them. This causes the tangled fibers contained in the paper pieces C to be untangled. The defibrated material made from the paper pieces C is transported to the separation unit 32.

[0037] The separation unit 32 separates the defibrated fibers. The separation unit 32 separates the relatively long fibers used to manufacture the sheet P3 from the defibrated material supplied from the defibrator unit 31. The separation unit 32 removes components unnecessary for manufacturing the sheet P3 from the defibrated material. Relatively short fibers contained in the defibrated material may cause a decrease in the strength of the sheet P3, so they are separated in the separation unit 32. The separation unit 32 also separates and removes coloring materials and additives contained in the paper pieces C. Technologies such as a disk mesh method can be applied to the separation unit 32.

[0038] Humidified air is supplied to the inside of the separation section 32 from the second humidifying section 66 of the third unit group 103.

[0039] The defibrated fibers, from which relatively short fibers and the like have been removed, are transported through the conduits in the separation section 32 and the piping 24 toward the deposition section 50 of the third unit group 103. Unnecessary materials such as relatively short fibers and coloring materials are discharged to the recovery section 35 through the piping 25.

[0040] The piping 24 connects the separation unit 32 and the deposition unit 50. The piping 24 transports the defibrated fibers, from which unnecessary fibers have been removed, from the separation unit 32 to the deposition unit 50. Humidified air is supplied to the piping 24 from the second humidifying unit 66 of the third unit group 103.

[0041] In the process of being conveyed through the pipe 24, the fibers from which unnecessary portions have been removed are mixed with a binder and the like by air, thereby forming a mixture. The pipe 24 is provided with a hopper 33 and a blower 34.

[0042] Hopper 33 is in communication with pipe 24 via supply path 331. Hopper 33 supplies a binder such as starch to pipe 24. Hopper 33 is provided with a valve (not shown) that adjusts the mass of the binder supplied from hopper 33 to pipe 24. This adjusts the mixing ratio of the fibers and the binder.

[0043] The piping 24 may be provided with a hopper 33 for supplying a binder, as well as a hopper 33 having a similar configuration to the hopper 33 for supplying a coloring material, an additive, or the like.

[0044] The blower 34 is provided in the pipe 24 at a position downstream of the hopper 33. The blower 34 generates an air current that transports the fibers downstream while mixing the binder and the like in the air to form a mixture.

[0045] As shown in FIG. 2, the path of the pipe 24 through which the fibers or mixture are transported by the air current is formed by connecting a plurality of pipes 241, 242, 243, 244, 245, and 246 together.

[0046] The pipe 241 extends straight from the separation section 32 in the +Z direction. The pipe 241 is an example of a straight section that constitutes the path of the piping 24. The pipe 241 is made of metal. Stainless steel, aluminum, etc. can be used as the metal that constitutes the pipe 241. The surface resistivity of the low-resistance member that constitutes the pipe 241 is, for example, less than 10^1 Ω / SQ.

[0047] Pipe 242 continues downstream of pipe 241 and forms a bent portion in the path of piping 24. Pipe 243 continues downstream of pipe 242 and forms a portion in the path of piping 24 that connects pipes 242 and 244.

[0048] Pipe 244 continues downstream of pipe 243 and constitutes a portion of the path of piping 24 where supply path 331 for supplying the binder from hopper 33 joins. Pipe 244 integrally constitutes supply path 331 for supplying the binder from hopper 33. For this reason, the path formed by pipe 244 includes a bent portion.

[0049] Pipe 245 continues downstream of pipe 244 and constitutes a portion of the path of piping 24 that connects pipe 244 to blower 34. Pipe 246 continues downstream of blower 34 and connects blower 34 to deposition unit 50. Pipe 246 constitutes, in the path of piping 24, a portion that extends straight from blower 34 in the +Z direction, a bent portion, and a portion that extends straight in the -Y direction toward deposition unit 50.

[0050] The pipes 242, 244 and the blower 34 are fixed to a frame (not shown) that supports the second unit group 102. For this reason, the pipes 243, 245 are made of a flexible material, which allows for misalignment between the members fixed to the frame.

[0051] The tubes 243 and 245 are made of, for example, a rubber-based material that is made conductive by adding carbon, etc. The surface resistivity of the members that make up the tubes 243 and 245 is, for example, 10^2 Ω / SQ or more and less than 10^6 Ω / SQ.

[0052] In this embodiment, the pipes 241, 242, 243, 244, 245, and 246 that form the path of the piping 24 are made of conductive materials and are grounded, which suppresses charging of the fibers or binders contained in the mixture, and prevents the fibers, binders, and the like from adhering to the path of the piping 24 due to static electricity.

[0053] On the other hand, if the bent portion of the path of the piping 24 is made of a highly conductive material, electrostatic induction may occur, which may cause fibers, binders, etc. to adhere to the path of the piping 24. In this embodiment, of the pipes 241 to 246 that make up the path of the piping 24, the pipes 242, 244, and 246 are made of a material that has a higher surface resistivity than the material that makes up the pipes 241, 243, and 245.

[0054] The tubes 242, 244, and 246 are made of a conductive resin such as ABS (Acrylonitrile Butadiene Styrene) resin, which is made conductive by adding carbon, etc. The surface resistivity of the medium resistance member that makes up the tubes 242, 244, and 246 is, for example, 10^6 Ω / SQ or more and 10^12 Ω / SQ or less.

[0055] The pipes 242, 244, and 246 are examples of bent portions in the path of the piping 24. The pipes 241, 243, and 245 are portions in the path of the piping 24 that are different from the bent portions, and are examples of other portions of the path of the piping 24.

[0056] 1, the collecting section 35 includes a filter (not shown) that filters out unnecessary materials such as relatively short fibers carried through the pipe 25 by the air current.

[0057] The compressor 38 generates compressed air. The filter may become clogged with fine particles from unwanted matter. The compressed air generated by the compressor 38 can be blown onto the filter to blow away any particles adhering to the filter, cleaning the filter.

[0058] The power supply unit 39 has a power supply device (not shown) that supplies power to the control unit 5 and the sheet manufacturing apparatus 1. The power supply unit 39 distributes power supplied from an external source to each component of the sheet manufacturing apparatus 1.

[0059] Although not shown, the control unit 5 includes a CPU (Central Processing Unit). The control unit 5 also includes a storage unit including a RAM (Random Access Memory), a ROM (Read Only Memory), etc. Various programs for controlling the sheet manufacturing apparatus 1 are stored in the storage unit.

[0060] The control unit 5 may include one or more processors that execute various processes according to a program, one or more dedicated hardware circuits such as an application specific integrated circuit (ASIC), or a combination thereof. The application specific integrated circuit (ASIC) executes at least some of the various processes.

[0061] The processor includes a CPU and memory such as RAM and ROM. The memory stores program code or instructions configured to cause the CPU to perform processes. Memory, i.e., computer-readable media, includes anything that can be accessed by a general-purpose or special-purpose computer.

[0062] The control unit 5 is electrically connected to each component such as a sheet forming unit 70 and a conveying unit 80, which will be described later, and controls the overall operation of these components.

[0063] The third unit group 103 deposits and compresses a mixture of fibrous materials to form a strip-shaped sheet P1. The third unit group 103 includes a depositing section 50, a first conveying section 61, a second conveying section 62, a first humidifying section 65, a second humidifying section 66, a draining section 68, a sheet forming section 70, and an upstream conveying unit 81 of the conveying units 80.

[0064] In the third unit group 103, the deposition section 50, the first conveying section 61, the second conveying section 62, the first humidifying section 65, the sheet forming section 70, and the upstream conveying unit 81 are arranged in the above order from upstream to downstream. The second humidifying section 66 is arranged below the first humidifying section 65.

[0065] The deposition unit 50 deposits the mixture containing the separated fibers in the air to generate the web W. The deposition unit 50 has a drum member 53, blade members 55 installed inside the drum member 53, a housing 51 that houses the drum member 53, and a suction unit 59. The mixture is taken into the drum member 53 from the pipe 24.

[0066] A first conveying unit 61 is disposed below the deposition unit 50. The first conveying unit 61 has a mesh belt 61a and five tension rollers (not shown) that tension the mesh belt 61a. The suction unit 59 faces the drum member 53 in the direction along the Z axis, with the mesh belt 61a sandwiched therebetween.

[0067] The blade member 55 is located inside the drum member 53 and is driven to rotate by a motor (not shown). The drum member 53 is a semi-cylindrical sieve. A mesh that functions as a sieve is provided on the downward-facing side of the drum member 53. The drum member 53 allows particles such as fibers and mixtures that are smaller than the size of the mesh openings of the sieve to pass from the inside to the outside.

[0068] The mixture is agitated by rotating blade members 55 inside drum member 53 and then discharged to the outside of drum member 53. Humidified air is supplied to the inside of drum member 53 from second humidifying section 66.

[0069] The suction unit 59 is disposed below the drum member 53. The suction unit 59 sucks air from inside the housing 51 through multiple holes in the mesh belt 61a. The multiple holes in the mesh belt 61a allow air to pass through but prevent fibers and binders contained in the mixture from passing through. As a result, the mixture discharged to the outside of the drum member 53 is sucked downward together with the air. The suction unit 59 is a suction device such as a blower.

[0070] The mixture is dispersed in the air within the housing 51 and is deposited on the upper surface of the mesh belt 61a by gravity and the suction of the suction section 59 to form the web W.

[0071] The mesh belt 61a is an endless belt stretched over five tension rollers. The mesh belt 61a rotates counterclockwise in FIG. 1 due to the rotation of the tension rollers. As a result, the mixture is continuously deposited on the mesh belt 61a, forming a web W. The web W contains a relatively large amount of air and is soft and inflated. The first conveying section 61 conveys the formed web W downstream by the rotation of the mesh belt 61a.

[0072] The second conveying unit 62 is located downstream of the first conveying unit 61 and conveys the web W in place of the first conveying unit 61. The second conveying unit 62 peels the web W from the upper surface of the mesh belt 61a and conveys it toward the sheet forming unit 70. The second conveying unit 62 is located above the conveying path of the web W and slightly upstream of the starting point of the return side of the mesh belt 61a. The +Y direction of the second conveying unit 62 and the -Y direction of the mesh belt 61a partially overlap in the vertical direction.

[0073] The second conveyor 62 includes a transport belt, multiple rollers, and a suction mechanism (not shown). The transport belt has multiple holes for air passage. The transport belt is stretched over multiple rollers and rotates with the rotation of the rollers.

[0074] The second conveying section 62 adsorbs the upper surface of the web W to the lower surface of the transport belt by using negative pressure generated by the suction mechanism. When the transport belt rotates in this state, the web W is adsorbed to the transport belt and transported downstream.

[0075] The first humidifying section 65 humidifies the web W containing fibers deposited in the deposition section 50 of the third unit group 103. More specifically, the first humidifying section 65 is, for example, a mist-type humidifier, and humidifies the web W transported by the second conveying section 62 by supplying mist M from below. The first humidifying section 65 is disposed below the second conveying section 62 and faces the web W transported by the second conveying section 62 in the direction along the Z axis. For example, an ultrasonic humidifying device can be used for the first humidifying section 65.

[0076] By humidifying the web W with the mist M, the function of the starch as a binder is promoted, and the strength of the sheet P3 is improved. In addition, since the web W is humidified from below, droplets from the mist are prevented from falling onto the web W. Furthermore, since the web W is humidified from the side opposite the contact surface between the transport belt and the web W, sticking of the web W to the transport belt is reduced. The second transport unit 62 transports the web W to the sheet forming unit 70.

[0077] The sheet forming unit 70 forms a strip-shaped sheet P1 by compressing the web W. The sheet forming unit 70 has processing rollers 71 and 72. The processing rollers 71 and 72 form a pair, and each has an electric heater built in to increase the temperature of the roller surface.

[0078] The processing rollers 71 and 72 are each a substantially cylindrical member. The rotation axis of the processing roller 71 and the rotation axis of the processing roller 72 are arranged along the X axis. With respect to the transport path of the web W, the processing roller 71 is arranged substantially above, and the processing roller 72 is arranged substantially below.

[0079] The processing rollers 71 and 72 are driven to rotate by a stepping motor (not shown). The web W is sandwiched between the processing rollers 71 and 72 and sent downstream while being heated and pressurized. That is, the web W continuously passes through the sheet forming unit 70 and is press-formed while being heated. By using the processing rollers 71 and 72 as a pair of forming members, the web W can be efficiently heated and pressurized.

[0080] By passing through the sheet forming section 70, the web W, which is soft and contains a relatively large amount of air, has the air contained therein reduced and the fibers are bound together by the binder, so that the web W is formed into a belt-like sheet P1. The belt-like sheet P1 is transported to the first unit group 101 by the upstream transport unit 81.

[0081] Second humidifier 66 is disposed below first humidifier 65. An evaporative humidifier can be used for second humidifier 66. An example of an evaporative humidifier is one that blows air onto moistened nonwoven fabric or the like to evaporate the moisture and generate humidified air.

[0082] The second humidifying section 66 humidifies a predetermined area of ​​the sheet manufacturing apparatus 1. The predetermined area is one or more of the storage section 132, the separation section 32, the pipes 21 and 24, and the inside of the drum member 53 of the accumulation section 50. Specifically, humidified air is supplied to the above-mentioned area from the second humidifying section 66 via multiple pipes (not shown). In each of the above-mentioned configurations, the humidified air suppresses the electrostatic charge on the paper pieces C, fibers, etc., and prevents them from adhering to the members due to static electricity.

[0083] The drainage unit 68 is a drainage tank. The drainage unit 68 is used in the first humidifying unit 65, the second humidifying unit 66, etc., and collects and stores old water. The drainage unit 68 can be removed from the sheet manufacturing apparatus 1 as needed, allowing the accumulated water to be discarded.

[0084] The strip-shaped sheet P1 transported to the first unit group 101 reaches the first cutting section 832 via the downstream transport unit 82. The first cutting section 832 cuts the strip-shaped sheet P1 in a direction intersecting the transport direction, for example, along the X-axis. The strip-shaped sheet P1 is cut into single sheets P2 by the first cutting section 832. The single sheets P2 are transported from the first cutting section 832 to the second cutting section 834.

[0085] The second cutting unit 834 cuts the single sheet P2 in the conveyance direction, for example, along the Y axis. More specifically, the second cutting unit 834 cuts the single sheet P2 near both sides in the direction along the X axis. The size of the sheet P3 to be manufactured can be adjusted by the first cutting unit 832 and the second cutting unit 834. This cuts the single sheet P2 into sheets P3 of a predetermined shape, such as A4 size or A3 size.

[0086] When the second cutting section 834 cuts the single sheets P2 into sheets P3, slit pieces S, which are scraps, are generated. The slit pieces S are transported in the approximately -Y direction to the shredding section 913, which is a shredder. The shredding section 913 shreds the slit pieces S into small pieces and supplies them to the junction 17. A mechanism may be installed between the shredding section 913 and the junction 17 to weigh the small pieces of the slit pieces S and supply them to the junction 17.

[0087] The sheet P3 is conveyed substantially upward and accumulated on the tray 191. In this manner, the sheet P3 is manufactured by the sheet manufacturing apparatus 1. The sheet P3 can be used as a substitute for, for example, copy paper.

[0088] As described above, the sheet manufacturing apparatus 1 according to the first embodiment can provide the following effects.

[0089] The sheet manufacturing apparatus 1 includes a defibrating unit 31 that defibrates paper pieces C to obtain defibrated material containing fibers. The sheet manufacturing apparatus 1 includes a separation unit 32 that separates fibers from the defibrated material supplied from the defibrating unit 31. The sheet manufacturing apparatus 1 includes a deposition unit 50 that deposits fibers to form a web W. The sheet manufacturing apparatus 1 includes a sheet forming unit 70 that compresses the web W to form a sheet P1. The sheet manufacturing apparatus 1 includes a pipe 24 that connects the separation unit 32 and the deposition unit 50 and transports the fibers from the separation unit 32 to the deposition unit 50. The path along which the fibers are transported in the pipe 24 is made of a conductive material, and the bent portion of the path is made of a medium-resistivity material that has a higher surface resistivity than the materials that form the rest of the path.

[0090] According to this, the bent portion is made of a medium-resistivity material having a higher surface resistivity than the material constituting the straight portion, so that the material forming the sheet P1, such as fibers, can be prevented from adhering to the bent portion, and thus the material forming the sheet P1, such as fibers, can be prevented from adhering to the path of the piping 24.

[0091] The pipe 24 has a straight section as another part of its path. The straight section is made of a material with a lower surface resistivity than the bent section, so that the material forming the sheet P1, such as fibers, can be neutralized. This prevents the material forming the sheet P1, such as fibers, from adhering to the path of the pipe 24.

[0092] The surface resistivity of the medium resistance member is 10^6 Ω / SQ or more and 10^12 Ω / SQ or less, which can prevent the material forming the sheet P1, such as fibers, from adhering to the bent portion.

[0093] The medium resistance member is made of a conductive resin, which makes it easy to obtain a bent portion made of the medium resistance member.

[0094] The other parts of the path are made of metal, which makes it easy to obtain a straight section made of a material with a surface resistivity lower than that of the medium resistance material.

[0095] The sheet manufacturing apparatus 1 according to the first embodiment of the present disclosure is basically configured as described above, but it is of course possible to modify or omit some of the configuration without departing from the gist of the present disclosure. The first embodiment and other embodiments described below can be combined with each other within the scope of technical compatibility. Other embodiments will be described below.

[0096] In the above embodiment, when the pipes constituting the path of the piping 24 are configured with a bent path and a straight path, the pipes may be divided into a bent pipe constituting the bent path and a straight pipe constituting the straight path. The bent pipes may be made of a medium resistance material, and the straight pipes may be made of a material having a surface resistivity lower than that of the medium resistance material.

[0097] For example, in the case of pipe 246 in the above embodiment, the straight path continuing from blower 34 is divided into a straight pipe. The bent path following the straight path is divided into a bent pipe. The straight path following the bent path and connected to deposition unit 50 is divided into a straight pipe. In this embodiment, the bent pipe is made of a medium resistance material, and the two straight pipes may be made of a material with a surface resistivity lower than that of the medium resistance material. In this case, the material constituting the two straight pipes may be metal.

[0098] In the above embodiment, the tubes 242, 244, and 246 do not have to be made of conductive resin such as ABS resin, which is made conductive by adding carbon or the like. For example, the tubes 242, 244, and 246 may be made of other resins or rubber-based materials which are made conductive by adding carbon or the like. Examples of other resins that can be used include PE (Polyethylene), PVC (Polyvinyl Chloride), and PTFE (Poly Tetra Fluoro Ethylene). When the tubes 242, 244, and 246 are made of rubber-based materials which are made conductive by adding carbon or the like, the tubes 243 and 245 do not need to be flexible. In this case, the tubes 243 and 245 may be made of metal, like the tube 241.

[0099] In the above embodiment, the outer surface of the pipe may not be conductive as long as the inner surface of the pipe constituting the path of the piping 24 is made of a conductive material. For example, the base material of the pipe may be made of a non-conductive resin material, and a conductive material may be applied or vapor-deposited onto the inner surface of the base material to form the inner surface of the pipe having the desired surface resistivity.

[0100] A configuration similar to that employed for the piping 24 in the above embodiment may be applied to the piping 21 connecting the junction 17 and the defibrating unit 31. This can prevent the paper pieces C from adhering to the path of the piping 21 through which the paper pieces C are transported.

[0101] A configuration similar to that employed for the piping 24 in the above embodiment may be applied to the piping 25 connecting the separation unit 32 and the recovery unit 35. This makes it possible to prevent unnecessary materials such as relatively short fibers and coloring materials removed from the defibrated material from adhering to the path of the piping 25. [Explanation of symbols]

[0102] 1...sheet manufacturing apparatus, 5...control section, 13...raw material supply device, 15...measuring section, 15a...sensor section, 17...junction section, 21, 24, 25...piping, 31...defibrating section, 32...separating section, 33...hopper, 34...blower, 35...recovery section, 38...compressor, 39...power supply section, 50...accumulating section, 51...housing, 53...drum member, 55...blade member, 59...suction section, 61...first conveying section, 61a...mesh belt, 62...second conveying section, 65...first humidifying section, 66...second humidifying section, 67...water supply section, 68...drainage section, 70...sheet To form the paper, 71, 72...processing rollers, 80...conveying unit, 81...upstream conveying unit, 82...downstream conveying unit, 101...first unit group, 102...second unit group, 103...third unit group, 131...raw material inlet, 132...storage section, 140...discharge section, 191...tray, 241, 242, 243, 244, 245, 246...pipes, 331...supply path, 832...first cutting section, 834...second cutting section, 913...shredding section, C...paper pieces, M...mist, P1, P2, P3...sheet, S...slit pieces, W...web.

Claims

1. a defibrating unit that defibrates a material containing fibers to obtain a defibrated material containing the fibers; a separation unit that separates the fibers from the defibrated material supplied from the defibrator unit; a deposition section for depositing the fibers to form a web; a sheet forming unit that compresses the web to form a sheet; a pipe connecting the separation unit and the deposition unit and transporting the fibers from the separation unit to the deposition unit; Equipped with a path through which the fibers are transported in the pipe is made of a conductive material, The bent portion of the path is made of a medium resistance material having a surface resistivity higher than that of a material constituting the other portion of the path. A sheet manufacturing apparatus characterized by:

2. The piping has a straight portion as another portion of the path. The sheet manufacturing apparatus according to claim 1 .

3. The surface resistivity of the medium resistance member is 10^6 Ω / SQ or more and 10^12 Ω / SQ or less. The sheet manufacturing apparatus according to claim 1 .

4. The medium resistance member is a conductive resin. The sheet manufacturing apparatus according to claim 1 .

5. The member constituting the other part of the path is metal. The sheet manufacturing apparatus according to claim 1 .

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