Sheet production device

Abstract

To provide a sheet production device capable of producing a second sheet having a desired thickness and a desired weight.SOLUTION: A sheet production device includes: a web generation unit that generates a web by depositing a raw material including fibers; a first sheet generation unit that generates a first sheet by compressing the web generated by the web generation unit; and a second sheet generation unit that generates a second sheet by compressing, in a thickness direction of the first sheet, a laminate in which a plurality of the first sheets generated by the first sheet generation unit are stacked.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] As described in Patent Document 1, a fiber structure manufacturing apparatus is known that includes a crushing section that roughly crushes waste paper, a defibrating section that defibrates the coarsely crushed pieces obtained in the crushing section, a depositing section that deposits the defibrated material obtained in the defibrating section on a flat surface, a heating and pressurizing section that heats and pressurizes the deposited web, a cutting section that cuts the sheet obtained in the heating and pressurizing section into a predetermined shape, and a sheet collecting section that collects the obtained sheet. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-7246 Summary of the Invention [Problem to be solved by the invention]

[0004] Sheets manufactured by such a fiber structure manufacturing apparatus are limited to those having a relatively thin thickness, which limits the uses of the sheets. [Means for solving the problem]

[0005] The sheet manufacturing apparatus of the present invention includes: a web generating unit that accumulates a raw material containing fibers to generate a web; a first sheet generating unit that pressurizes the web generated by the web generating unit to generate a first sheet; and a second sheet generating section that generates a second sheet by pressing a stack of a plurality of the first sheets generated by the first sheet generating section in the thickness direction of the first sheets. [Brief explanation of the drawings]

[0006] [Figure 1]FIG. 1 is a schematic diagram illustrating a sheet manufacturing apparatus according to an embodiment of the present invention. [Figure 2] FIG. 2 is a schematic diagram illustrating the stock unit, the supply unit, and the second sheet producing unit of the sheet manufacturing apparatus shown in FIG. [Figure 3] FIG. 3 is a perspective view showing an example of a binder supplied from an additive supply unit of the sheet manufacturing apparatus shown in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0007] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A sheet manufacturing apparatus according to the present invention will now be described in detail with reference to preferred embodiments shown in the accompanying drawings.

[0008] <Embodiment> Fig. 1 is a schematic diagram illustrating a sheet manufacturing apparatus according to an embodiment of the present invention. Fig. 2 is a schematic diagram illustrating a stock unit, a supply unit, and a second sheet generating unit of the sheet manufacturing apparatus shown in Fig. 1. Fig. 3 is a perspective view illustrating an example of a binder supplied from the additive supply unit of the sheet manufacturing apparatus shown in Fig. 1.

[0009] In the following, the upper side of Figures 1 and 2 may be referred to as "top" or "upper side," and the lower side may be referred to as "bottom" or "lower side." The left side of Figure 2 may be referred to as "left" or "left side," and the right side may be referred to as "right" or "right side." Figure 1 is a schematic diagram, and the relative positions, orientations, sizes, etc. of the components of the sheet manufacturing apparatus 100 are not limited to those shown. In Figure 1, the direction in which the coarse fragments M2, defibrated material M3, first sorted material M4-1, second sorted material M4-2, first web M5, finely divided material M6, mixture M7, second web M8, first sheet S1, and second sheet S2 are transported, i.e., the direction indicated by the arrow, is also referred to as the transport direction. The tip of the arrow in Figure 1 is also referred to as the "downstream side" in the transport direction, and the base of the arrow in Figure 1 is also referred to as the "upstream side" in the transport direction.

[0010] 1 is a sheet manufacturing apparatus 100 that produces a second sheet S2 from a raw material M1, which is waste paper such as used copy paper. The second sheet S2 is a cardboard or board having a thickness of about 0.5 mm to 500 mm.

[0011] As shown in FIG. 1, the sheet manufacturing apparatus 100 includes a raw material supply section 11, a crushing section 12, a defibrating device 13, a sorting section 14, a first web generating section 15, a fine dividing section 16, a mixing section 17, a dispersion section 18, a second web generating section 19, a first sheet generating section 20, a cutting section 21, a storage section 22, a supply section 23, a second sheet generating section 24, and a recovery section 27.

[0012] The sheet manufacturing apparatus 100 also includes a humidifying section 231, a humidifying section 232, a humidifying section 233, a humidifying section 234, a humidifying section 235, and a humidifying section 236. In addition, the sheet manufacturing apparatus 100 also includes a blower 261, a blower 262, and a blower 263.

[0013] In addition, in the sheet manufacturing apparatus 100, a raw material supply process, a coarse crushing process, a defibrating process, a sorting process, a first web generating process, a cutting process, a mixing process, a loosening process, a second web generating process (web generating process), a first sheet generating process, a cutting process, a supply process, and a second sheet generating process are performed in this order.

[0014] Each part of the sheet manufacturing apparatus 100 is electrically connected to a control device 28. The operation of each part is controlled by the control device 28.

[0015] As shown in FIG. 1, the control device 28 includes a control unit 281, a storage unit 282, and a communication unit 283.

[0016] The control unit 281 has at least one processor and executes various programs stored in the storage unit 282. The processor may be, for example, a CPU (Central Processing Unit). The control unit 281 also has various functions, such as a function to control the driving of each part of the device related to sheet manufacturing. The storage unit 282 stores, for example, programs related to sheet manufacturing.

[0017] The communication unit 283 is configured by, for example, an I / O interface, and communicates with each unit of the sheet manufacturing apparatus 100. The communication unit 283 also has a function of communicating with a computer or server (not shown) via, for example, a network.

[0018] The control device 28 may be built into the sheet manufacturing apparatus 100, or may be provided in an external device such as an external computer. Furthermore, the control unit 281 and the storage unit 282 may be integrated into one unit, for example, or the control unit 281 may be built into the sheet manufacturing apparatus 100 and the storage unit 282 may be provided in an external device such as an external computer, or the storage unit 282 may be built into the sheet manufacturing apparatus 100 and the control unit 281 may be provided in an external device such as an external computer.

[0019] The configuration of each part will be explained below. The raw material supply unit 11 is a part that performs a raw material supply step of supplying raw material M1 to the crushing unit 12. This raw material M1 is a sheet-like material made of a fiber-containing material including cellulose fibers and chemical fibers. Cellulose fibers are any fibrous material whose main component is cellulose as a compound, and may contain hemicellulose and lignin in addition to cellulose. Chemical fibers are fibrous materials made of fiber compounds including polyester, polyethylene, polypropylene, acrylic, nylon, urethane, etc. The raw material M1 can be in any form, such as woven fabric or nonwoven fabric. The raw material M1 may be, for example, recycled paper made by disintegrating waste paper and regenerating it, or synthetic paper such as Yupo paper (registered trademark), or it does not have to be recycled paper.

[0020] The crushing unit 12 is a part that performs a crushing step of crushing the raw material M1 supplied from the raw material supply unit 11 in air or the like. The crushing unit 12 has a pair of crushing blades 121 and a chute 122.

[0021] The pair of crushing blades 121 rotate in opposite directions to each other, thereby crushing the raw material M1 between them, i.e., cutting it into crushed pieces M2. The shape and size of the crushed pieces M2 are preferably suitable for the defibration process in the defibration device 13. Examples of the shape of the crushed pieces M2 include small pieces with a square planar shape, rectangular pieces, and particularly small pieces with a strip shape. Furthermore, the size of the crushed pieces M2 is preferably small pieces with an average side length of 100 mm or less, and more preferably small pieces with an average side length of 3 mm or more and 70 mm or less. The shape of the small pieces may be other than square or rectangular. Furthermore, the thickness is preferably 0.07 mm or more and 0.10 mm or less.

[0022] The chute 122 is disposed below the pair of crushing blades 121 and is, for example, conical or funnel-shaped, so that the chute 122 can receive the coarsely crushed pieces M2 that have been crushed by the crushing blades 121 and dropped.

[0023] Furthermore, above the chute 122, a humidifying section 231 is disposed adjacent to the pair of coarse crushing blades 121. The humidifying section 231 humidifies the coarsely crushed pieces M2 inside the chute 122. This humidifying section 231 is configured as an evaporative humidifier that has a filter (not shown) that contains moisture, and supplies humidified air with increased humidity to the coarsely crushed pieces M2 by passing air through the filter. By supplying humidified air to the coarsely crushed pieces M2, it is possible to prevent the coarsely crushed pieces M2 from adhering to the chute 122, etc. due to electrostatic force.

[0024] The chute 122 is connected to the defibration device 13. The coarse fragments M2 collected by the chute 122 are supplied to the defibration device 13. The defibrator 13 is a part that performs the defibration step of defibrating the coarse fragments M2 in the air, i.e., in a dry manner. By the defibration process in this defibrator 13, defibrated material M3 can be generated from the coarse fragments M2. Here, "defibrating" refers to untangling the coarse fragments M2, which are made up of multiple fibers bonded together, into individual fibers. This untangled material becomes the defibrated material M3. The shape of the defibrated material M3 is linear or strip-like. Furthermore, the defibrated material M3 may exist in a state where it is entangled with other defibrated material M3 and forms a mass, that is, in a state where it forms so-called "lumps."

[0025] Furthermore, the defibrator 13 can generate an air flow, i.e., an air current, directed toward the sorting section 14 by rotating a rotor (not shown). This allows the coarse fragments M2 to be introduced from the pipe 241 to the upstream side of the defibrator 13, and after defibration processing, the defibrated material M3 can be sent to the sorting section 14 via the pipe 242.

[0026] A pipe 242 is connected to the downstream side of the defibrator 13. A blower 261, which is composed of, for example, a turbo fan, is installed midway through the pipe 242. The blower 261 is an airflow generating device that generates an airflow toward the sorting section 14. This promotes the introduction of the coarse fragments M2 into the defibrator 13 and the delivery of the defibrated material M3 to the sorting section 14. The defibrator 13 is structurally designed to smoothly pass through and defibrate the coarse fragments M2, which are the raw material, but operation of the blower 261 installed downstream of the defibrator 13 promotes the passage and defibration process of the coarse fragments M2 within the defibrator 13. The blower 261 may also be installed upstream of the defibrator 13.

[0027] The sorting unit 14 is a section that performs a sorting process to sort the defibrated material M3 according to fiber length. In the sorting unit 14, the defibrated material M3 is sorted into a first sorted material M4-1 and a second sorted material M4-2 that has a longer fiber length than the first sorted material M4-1. The first sorted material M4-1 has a size suitable for the subsequent production of the first sheet S1 and second sheet S2. On the other hand, the second sorted material M4-2 includes, for example, material that is insufficiently defibrated or material in which defibrated fibers have excessively aggregated together.

[0028] The sorting unit 14 has a drum unit 141 and a housing unit 142 that houses the drum unit 141.

[0029] The drum part 141 is a sieve made up of a cylindrical mesh body that rotates around its central axis. The defibrated material M3 flows into this drum part 141. As the drum part 141 rotates, defibrated material M3 that is smaller than the mesh openings is sorted as first sorted material M4-1, and defibrated material M3 that is larger than the mesh openings is sorted as second sorted material M4-2.

[0030] The first sorted item M4-1 falls from the drum section 141. Meanwhile, the second sorted material M4-2 is sent out to a pipe 243 connected to the drum section 141. The end of the pipe 243 opposite the drum section 141, i.e., the downstream end, is connected to the middle of the pipe 241. The second sorted material M4-2 that has passed through this pipe 243 merges with the coarsely crushed fragments M2 inside the pipe 241 and flows into the defibration device 13 together with the coarsely crushed fragments M2. As a result, the second sorted material M4-2 is returned to the defibration device 13 and is defibrated together with the coarsely crushed fragments M2.

[0031] The first sorted material M4-1 that has fallen from the drum unit 141 disperses in the air as it falls, heading toward the first web generating unit 15 located below the drum unit 141. The first web generating unit 15 is a unit that performs the first web generating step of generating a first web M5 from the first sorted material M4-1. The first web generating unit 15 has a mesh belt 151, three tension rollers 152, and a suction unit 153.

[0032] The mesh belt 151 is an endless belt on which the first sorted material M4-1 accumulates. The mesh belt 151 is looped around three tension rollers 152. As the tension rollers 152 rotate, the first sorted material M4-1 on the mesh belt 151 is transported downstream.

[0033] The size of the first sorted material M4-1 is equal to or larger than the mesh openings of the mesh belt 151. This restricts the first sorted material M4-1 from passing through the mesh belt 151, and therefore the first sorted material M4-1 can be accumulated on the mesh belt 151. Furthermore, while being accumulated on the mesh belt 151, the first sorted material M4-1 is transported downstream together with the mesh belt 151, and is thus generated as a layered first web M5.

[0034] Furthermore, the first sorted material M4-1 may contain, for example, dust and dirt. Dust and dirt may be generated, for example, by crushing or defibrating. Such dust and dirt will be collected in the collection unit 27, which will be described later.

[0035] The suction unit 153 is a suction mechanism that sucks air from below the mesh belt 151. This allows dust and dirt that has passed through the mesh belt 151 to be sucked in together with the air.

[0036] Furthermore, suction unit 153 is connected to collection unit 27 via pipe 244. Dust and dirt sucked by suction unit 153 are collected in collection unit 27.

[0037] A pipe 245 is further connected to the collection unit 27. A blower 262 is installed midway through the pipe 245. By operating the blower 262, a suction force can be generated in the suction unit 153. This promotes the generation of the first web M5 on the mesh belt 151. Dust and dirt are removed from this first web M5. By operating the blower 262, the dust and dirt pass through the pipe 244 and reach the collection unit 27.

[0038] The housing 142 is connected to the humidifying section 232. The humidifying section 232 is configured as an evaporative humidifier. This allows humidified air to be supplied into the housing 142. This humidified air can humidify the first sorted items M4-1, thereby preventing the first sorted items M4-1 from adhering to the inner wall of the housing 142 due to electrostatic force.

[0039] A humidifying unit 235 is disposed downstream of the sorting unit 14. The humidifying unit 235 is configured with an ultrasonic humidifier that sprays water. This allows moisture to be supplied to the first web M5, thereby adjusting the moisture content of the first web M5. This adjustment makes it possible to suppress adhesion of the first web M5 to the mesh belt 151 due to electrostatic force. As a result, the first web M5 is easily peeled off from the mesh belt 151 at the position where the mesh belt 151 is folded back by the tension roller 152.

[0040] The dividing unit 16 is disposed downstream of the humidifying unit 235. The dividing unit 16 is a section that performs a dividing step of dividing the first web M5 peeled off from the mesh belt 151. The dividing unit 16 has a rotatably supported propeller 161 and a housing unit 162 that houses the propeller 161. The rotating propeller 161 can divide the first web M5. The divided first web M5 becomes divided bodies M6. The divided bodies M6 descend within the housing unit 162.

[0041] The housing 162 is connected to the humidifier 233. The humidifier 233 is configured as an evaporative humidifier. This allows humidified air to be supplied into the housing 162. This humidified air can also prevent the fragmented bodies M6 from adhering to the propeller 161 or the inner wall of the housing 162 due to electrostatic force.

[0042] A mixing section 17 is disposed downstream of the dividing section 16. The mixing section 17 is a section where a mixing step of mixing the divided bodies M6 with an additive is performed. The mixing section 17 has an additive supply section 171, a pipe 172, and a blower 173.

[0043] The pipe 172 connects the housing 162 of the subdivision section 16 and the housing 182 of the dispersion section 18, and is a flow path through which the mixture M7 of the subdivision bodies M6 and the additive passes.

[0044] An additive supply unit 171 is connected to the middle of the pipe 172. The additive supply unit 171 has a housing unit 170 in which an additive is accommodated, and a screw feeder 174 provided in the housing unit 170. By rotation of the screw feeder 174, the additive in the housing unit 170 is pushed out of the housing unit 170 and supplied into the pipe 172. The additive supplied into the pipe 172 is mixed with the pulverized body M6 to form a mixture M7.

[0045] Examples of additives supplied from the additive supply unit 171 include binders that bind fibers together, colorants that color fibers, aggregation inhibitors that inhibit fiber aggregation, flame retardants that make fibers less flammable, and paper strength agents that increase the paper strength of the second sheet S2. One or more of these may be used in combination. The following describes, as an example, a case where the additive is binder P1. The strength of the second sheet S2 can be increased by including a binder that binds fibers together in the additive.

[0046] As shown in FIG. 3, the binder P1 has a two-layer structure including a core material 201A made of a first resin and a coating layer 202A made of a second resin having a lower melting point or softening point than the first resin.

[0047] The first resin and the second resin may be the same or different materials, but it is preferable to use a thermoplastic resin. Examples of thermoplastic resins include polyolefins such as AS resin, ABS resin, polyethylene, polypropylene, and ethylene-vinyl acetate copolymer (EVA), modified polyolefins, acrylic resins such as polymethyl methacrylate, polyesters such as polyvinyl chloride, polystyrene, polyethylene terephthalate, and polybutylene terephthalate, polyamides (Nylon: registered trademark) such as nylon 6, nylon 46, nylon 66, nylon 610, nylon 612, nylon 11, nylon 12, nylon 6-12, and nylon 6-66, polyamideimide, polyphenylene ether, polyacetal, and polyester. Examples of suitable thermoplastic resins include liquid crystal polymers such as polyethylene terephthalate (PET), polyphenylene oxide, modified polyphenylene ether, polyether ether ketone, polycarbonate, polyphenylene sulfide, thermoplastic polyimide, polyetherimide, and aromatic polyester; fluorine-based resins such as polytetrafluoroethylene; and various thermoplastic elastomers such as styrenes, polyolefins, polyvinyl chlorides, polyurethanes, polyesters, polyamides, polybutadiene, trans-polyisoprene, fluororubbers, and chlorinated polyethylenes. These may be used alone or in combination. Polyesters or resins containing polyesters are particularly preferred as thermoplastic resins. Biomass plastics or biodegradable plastics such as polylactic acid, polycaprolactone, modified starch, polyhydroxybutyrate, polybutylene succinate, and polybutylene succinate adipate may also be included. This improves environmental compatibility. Curable resins such as thermosetting resins and photocurable resins may also be included. Examples of thermosetting resins include epoxy resins and phenolic resins, and the composition may contain one or more of these.

[0048] Among these, the first resin is preferably composed of polyethylene terephthalate. This increases the stiffness of the binder P1, thereby sufficiently increasing the rigidity of the first sheet S1 and the second sheet S2. The second resin is preferably composed of at least one selected from the group consisting of polyolefins and polyamides. This allows the binder P1 to function excellently as a binder.

[0049] The difference in softening point between the first resin and the second resin is preferably 10°C or more, and more preferably 20°C or more.

[0050] Furthermore, the boundary between the core material 201A and the coating layer 202A does not need to be clear. That is, even if the binder P1 has a softening point that gradually decreases from the center toward the outer periphery, the above-described effects can be obtained.

[0051] The average fiber length of the binder P1 is preferably 1.0 mm or more and 20 mm or less, and more preferably 1.5 mm or more and 15 mm or less, which allows for good binding between the fibers and sufficient increase in the rigidity of the first sheet S1 and the second sheet S2.

[0052] From the same viewpoint, the average fiber width of the binder P1 is preferably 10 μm or more and 100 μm or less, and more preferably 15 μm or more and 50 μm or less.

[0053] The additives supplied from the additive supply unit 171 may contain other binders in addition to the binder P1. Examples of other binders include naturally occurring components such as starch, dextrin, glycogen, amylose, hyaluronic acid, kudzu, konjac, potato starch, etherified starch, esterified starch, natural gum glue, fiber-derived glue, seaweed, and animal protein, as well as polyvinyl alcohol, polyacrylic acid, and polyacrylamide. One or a combination of two or more selected from these may be used, but naturally occurring components are preferred, and starch is more preferred.

[0054] A blower 173 is installed in the pipe 172 downstream of the additive supply unit 171. The action of a rotating part such as a blade of the blower 173 promotes mixing of the fragmented materials M6 and the binder P1. The blower 173 can also generate an airflow directed toward the dispersion unit 18. This airflow can agitate the fragmented materials M6 and the binder P1 within the pipe 172. As a result, the mixture M7 is transported to the dispersion unit 18 in a state in which the fragmented materials M6 and the binder P1 are uniformly dispersed. The fragmented materials M6 in the mixture M7 are also loosened as they pass through the pipe 172, becoming finer fibers.

[0055] The blower 173 is electrically connected to the control device 28, and its operation is controlled by the control device 28. The amount of air sent into the drum 181 can be adjusted by adjusting the airflow rate of the blower 173.

[0056] Although not shown, the end of the pipe 172 on the drum 181 side is branched into two, and the branched ends are each connected to an inlet port (not shown) formed on the end face of the drum 181.

[0057] 1 is a section that performs a disentangling process of disentangling and releasing entangled fibers in the mixture M7. The dispersion section 18 has a drum 181 that introduces and releases the defibrated mixture M7, and a housing 182 that houses the drum 181.

[0058] Drum 181 is a sieve made of a cylindrical mesh body that rotates around its central axis. As drum 181 rotates, fibers and the like in mixture M7 that are smaller than the mesh openings can pass through drum 181. At that time, mixture M7 is loosened and released together with air. In other words, drum 181 functions as a release section that releases material containing fibers.

[0059] The drum 181 is connected to a drive source (not shown) and rotates by the torque output from the drive source. The drive source is electrically connected to the control device 28, which controls the operation of the drive source.

[0060] Furthermore, housing 182 is connected to humidifier 234. Humidifier 234 is configured as an evaporative humidifier. This allows humidified air to be supplied into housing 182. This humidified air can humidify the inside of housing 182, and therefore, it is also possible to prevent mixture M7 from adhering to the inner wall of housing 182 due to electrostatic force.

[0061] The mixture M7 released from the drum 181 falls while dispersing in the air, and heads toward the second web generating unit 19 located below the drum 181. The second web generating unit 19 is a section that performs the second web generating step of depositing the mixture M7 to generate a second web M8, which is a deposit. The second web generating unit 19 has a mesh belt 191, a tension roller 192, and a suction unit 193.

[0062] The mesh belt 191 is a mesh member, and in the illustrated configuration, is configured as an endless belt. The mixture M7 dispersed and discharged by the dispersion unit 18 is deposited on the mesh belt 191. The mesh belt 191 is wound around four tension rollers 192. The rotation of the tension rollers 192 transports the mixture M7 on the mesh belt 191 downstream.

[0063] In the illustrated configuration, a mesh belt 191 is used as an example of a mesh member, but the present invention is not limited to this, and for example, a flat plate-shaped member may also be used.

[0064] Furthermore, most of the mixture M7 on the mesh belt 191 has a size equal to or larger than the mesh openings of the mesh belt 191. This prevents the mixture M7 from passing through the mesh belt 191, and therefore allows the mixture M7 to be deposited on the mesh belt 191. Furthermore, while being deposited on the mesh belt 191, the mixture M7 is transported downstream together with the mesh belt 191, and is thus produced as a layered second web M8.

[0065] The suction unit 193 is a suction mechanism that sucks air from below the mesh belt 191. This allows the mixture M7 to be sucked onto the mesh belt 191, thereby facilitating the deposition of the mixture M7 on the mesh belt 191.

[0066] A pipe 246 is connected to the suction unit 193. A blower 263 is installed midway along the pipe 246. By operating the blower 263, the suction unit 193 can generate a suction force.

[0067] A detection unit 25, which will be described later, is installed on the opposite side of the mesh belt 191 from the second web M8. The detection unit 25 is capable of detecting physical quantities such as the weight and thickness of the second web M8 formed on the mesh belt 191. The installation location of the detection unit 25 is not limited to the configuration shown in the figure.

[0068] The humidifying section 236 is disposed downstream (to the right) of the dispersion section 18. The humidifying section 236 is configured with an ultrasonic humidifier similar to the humidifying section 235. This allows moisture to be supplied to the second web M8, thereby adjusting the moisture content of the second web M8. This adjustment makes it possible to suppress adhesion of the second web M8 to the mesh belt 191 due to electrostatic force. This allows the second web M8 to be easily peeled off from the mesh belt 191 at the position where the mesh belt 191 is folded back by the tension roller 192.

[0069] The total amount of water added to the humidifying units 231 to 236 is preferably, for example, 0.5 parts by mass or more and 20 parts by mass or less per 100 parts by mass of the material before humidification.

[0070] A first sheet generating unit 20 is disposed downstream (to the right) of the second web generating unit 19. The first sheet generating unit 20 is a unit that performs a first sheet generating step of generating a first sheet S1 from the second web M8. The first sheet generating unit 20 includes a first pressurizing unit 201 and a first heating unit 202.

[0071] The first pressurizing unit 201 has a pair of calender rollers 203, and can pressurize the second web M8 between the calender rollers 203 without heating it. This increases the density of the second web M8. When heating, the degree of heating is preferably such that the binder P1 does not melt. The second web M8 is then transported toward the first heating unit 202. One of the pair of calender rollers 203 is a driven roller driven by the operation of a motor (not shown), and the other is a driven roller.

[0072] The first heating section 202 has a pair of heating rollers 204, and can apply pressure to the second web M8 while heating it between the heating rollers 204. This heating and pressurizing melts the binder P1 in the second web M8, and the fibers are bound together via the molten binder P1. This produces a first sheet S1. The first sheet S1 is then transported toward the cutting section 21. One of the pair of heating rollers 204 is a drive roller driven by the operation of a motor (not shown), and the other is a driven roller.

[0073] The cutting unit 21 is disposed downstream (to the right) of the first sheet producing unit 20. The cutting unit 21 is a part that performs a cutting step to cut the first sheet S1. The cutting unit 21 has a first cutter 211 and a second cutter 212.

[0074] The first cutter 211 cuts the first sheet S1 in a direction intersecting the conveying direction of the first sheet S1, particularly in a direction perpendicular to the conveying direction of the first sheet S1.

[0075] The second cutter 212 cuts the first sheet S1 in a direction parallel to the conveyance direction of the first sheet S1 downstream of the first cutter 211. This cutting removes unnecessary portions from both side edges in the width direction of the first sheet S1 to adjust the width of the first sheet S1.

[0076] By cutting with the first cutter 211 and the second cutter 212 in this manner, a first sheet S1 having a desired shape and size is obtained.

[0077] A stock unit 22 is provided downstream (to the right) of the cutting unit 21. The first sheet S1 obtained through the cutting unit 21 is further conveyed downstream to the stock unit 22, where it is stored.

[0078] The stock section 22 is a section for temporarily storing the first sheets S1 in a state where they are stacked in the thickness direction. The number of sheets stored in the stock section 22 is not particularly limited, but can be, for example, between 5 and 100.

[0079] 2, the sheet manufacturing apparatus 100 includes a supply unit 23 that supplies the first sheet S1 from the stock unit 22 to the second sheet generating unit 24. The supply unit 23 includes a feed roller 231A that feeds the stacked first sheet S1 one by one, and a pair of transport rollers 232A. The feed roller 231A is connected to a motor 233A that serves as a drive source. The motor 233A is electrically connected to a control unit 281, and the rotation speed and rotation timing of the motor 233A are controlled by the control unit 281.

[0080] The feed roller 231A rotates while in contact with the uppermost first sheet S1 among the stacked first sheets S1, thereby feeding out the first sheets S1 one by one.

[0081] Although not shown, a mounting plate on which one or more stored first sheets S1 are placed and a biasing member such as a spring that biases the mounting plate upward are provided at the bottom of stock section 22. With this configuration, regardless of the number of first sheets S1 stored in stock section 22, feed roller 231A contacts the uppermost first sheet S1 with a constant force, thereby enabling the uppermost first sheets S1 to be reliably fed one by one.

[0082] The first sheet S1 sent out to the left in FIG. 2 by the sending roller 231A is sandwiched between a pair of conveying rollers 232A rotating in opposite directions, and is further conveyed to the second sheet generating unit 24 located on the left side in FIG. One of the pair of transport rollers 232A is connected to a motor 234A, which is a drive source, and is a driven roller that is driven by the operation of the motor 234A. The other of the pair of transport rollers 232A is a driven roller. The motor 234A is electrically connected to the control unit 281, and the rotation speed and rotation timing of the motor 234A are controlled by the control unit 281.

[0083] The first sheets S1 conveyed by the pair of conveyance rollers 232A are supplied to the second sheet generating unit 24 one by one.

[0084] The sheet mechanism in the supply unit 23 is not limited to the one using the feed roller 231A as shown in the figure, but may be configured to have, for example, a suction mechanism and a suction cup that can reduce the pressure inside by the suction mechanism.

[0085] In addition, although not shown, the supply section 23 may have an anti-static mechanism for the first sheet S1, i.e., an electrostatic elimination mechanism for removing static electricity from the first sheet S1, in order to reliably feed out the first sheet S1 one by one.

[0086] 1 and 2, the second sheet generating unit 24 performs a second sheet generating step in which a laminate S100, which is made up of multiple first sheets S1, is pressed in the thickness direction of the first sheets S1 to generate second sheets S2. The second sheet generating unit 24 has a pair of heating and pressurizing blocks 241A and 241B and a movement mechanism 242B that moves the heating and pressurizing blocks toward and away from each other. The movement mechanism 242B is connected to the heating and pressurizing block 241B.

[0087] The heating and pressurizing blocks 241A and 241B are provided facing each other in the vertical direction, with the heating and pressurizing block 241A located at the bottom and the heating and pressurizing block 241B located above the heating and pressurizing block 241A. In the second sheet producing section 24, the first sheets S1 supplied by the supply section 23 are first conveyed to the upper surface of the heating and pressing block 241A, and are stacked one by one to form a stack S100 in which a predetermined number of sheets are stacked.

[0088] The number of first sheets S1 in the laminate S100 is not particularly limited, but is set to be approximately 2 or more and 100 or less. Although not shown, the second sheet producing unit 24 may be provided with a positioning device for aligning the positions of the first sheets S1 to be stacked one on the other.

[0089] Heating and pressurizing block 241A is fixed in position. On the other hand, heating and pressurizing block 241B is moved up and down by driving of moving mechanism 242B, and approaches and moves away from heating and pressurizing block 241A. However, this configuration is not limited thereto, and a configuration in which heating and pressurizing block 241B is fixed in position and heating and pressurizing block 241A moves up and down, or a configuration in which both heating and pressurizing blocks 241A and 241B move up and down may also be used.

[0090] Heaters 243A and 243B are embedded in the heating and pressurizing blocks 241A and 241B, respectively, and the heating and pressurizing blocks 241A and 241B can simultaneously apply heat and pressure to the layered body S100.

[0091] With the laminate S100 present between the heating and pressing blocks 241A and 241B, the heaters 243A and 243B are operated to heat the heating and pressing blocks 241A and 241B, and the moving mechanism 242B is driven to lower the heating and pressing block 241B, thereby heating and pressing the laminate S100 at a desired temperature and pressure for a desired period of time.

[0092] When heating and pressurizing of the laminate S100 is completed, the heating and pressurizing block 241B rises and the heating and pressurizing blocks 241A and 241B move apart, thereby obtaining the second sheet S2. The obtained second sheet S2 is removed by an operator or a conveying mechanism (not shown).

[0093] Although not shown, the sheet manufacturing apparatus 100 may also have a second sheet stock section that stores the produced second sheets S2.

[0094] In this second-sheet producing section 24, the binder P1 of the first sheet S1 melts and seeps into the spaces between the fibers of adjacent first sheets S1. This allows the production of a second sheet S2 in which first sheets S1 are bonded together. Furthermore, by appropriately adjusting the thickness and number of first sheets S1 and the degree of pressure applied in the second-sheet producing section 24, a second sheet S2 having a desired thickness and weight can be produced.

[0095] It should be noted that the heating and pressurization by the heating and pressurization blocks 241A and 241B do not have to be simultaneous. For example, pressurization may be performed without activating the heaters 243A and 243B, and then heating may be initiated by activating the heaters 243A and 243B in that pressurized state or with the pressurization released.

[0096] Furthermore, the second sheet generating unit 24 is not limited to the above configuration, and may have a configuration including a heating and pressure roller like the first sheet generating unit 20. In this case, the second sheet generating unit 24 may have a configuration in which both heating and pressure blocks 241A and 241B are replaced with heating and pressure rollers, or alternatively, the second sheet generating unit 241A may be used as is, and the second sheet generating unit 241B may be replaced with a heating and pressure roller.

[0097] As described above, the sheet manufacturing apparatus 100 includes the second web generating unit 19 as a web generating unit that deposits the mixture M7 as a fiber-containing raw material to generate the second web M8, the first sheet generating unit 20 that pressurizes the second web M8 generated by the second web generating unit 19 to generate the first sheet S1, and the second sheet generating unit 24 that pressurizes the laminate S100, in the thickness direction of the first sheet S1, where a plurality of first sheets S1 generated by the first sheet generating unit 20 are stacked. With this configuration, a second sheet S2 having a desired thickness and weight can be generated by appropriately adjusting and setting various conditions such as the thickness, density, weight, etc. of the first sheet S1 generated via the web generating unit and the first sheet generating unit 20, the number of first sheets S1 stacked in the second sheet generating unit 24, and the degree of heating and pressure in the second sheet generating unit 24.

[0098] It should be noted that both the first sheet generating unit 20 and the second sheet generating unit 24 may be configured to apply pressure only without applying heat, or only one of them may be configured to apply pressure only without applying heat.

[0099] The second web M8 contains a binder P1 that binds the fibers together, and the first sheet producing section 20 heats and presses the second web M8, while the second sheet producing section 24 heats and presses the first sheet S1. This allows for good bonding of the fibers, increasing the strength of the first sheet S1 and increasing the bonding strength between the first sheets S1 in the second sheet S2. As a result, a higher quality second sheet S2 can be produced.

[0100] The binder P1 may be omitted from the second web M8, in which case the first sheet producing section 20 and the second sheet producing section 24 may be configured to only apply pressure.

[0101] As described above, the binder P1 has a core 201A made of a first resin and a coating layer 202A made of a second resin with a lower melting point than the first resin, which covers the core 201A. This makes it possible to both strengthen the stiffness of the binder P1 and improve its function as a binder. As a result, a higher quality second sheet S2 can be produced.

[0102] The binder P1 is not limited to the above configuration, and may have other shapes or forms such as granular, flaky, semi-solid, liquid, etc. Furthermore, the binder P1 may be configured only by the coating layer 202A, omitting the core material 201A.

[0103] The laminate S100 also includes a cutting unit 21 that cuts the first sheet S1 generated by the first sheet generating unit 20 into a predetermined shape, and the laminate S100 is formed by stacking multiple first sheets S1 cut by the cutting unit 21. This allows the thickness of the laminate S100 to be adjusted by adjusting the number of stacked first sheets S1. The shape of the second sheet S2 is also easily adjusted. Therefore, a second sheet S2 having a desired thickness and weight, particularly a second sheet S2 having a desired thickness, weight, and shape, can be easily generated.

[0104] The direction in which the first sheets S1 are stacked is not particularly limited, and for example, adjacent first sheets S1 may be stacked with a 90° offset. In this case, the extending direction of the fibers in the adjacent first sheets S1 will be different, and the shear strength can be made as similar as possible in any direction.

[0105] The laminate S100 is not limited to the above configuration, and may be produced by folding back a long, strip-shaped first sheet S1 multiple times without cutting by the cutting unit 21. In this case, the folded-back portions of the first sheet S1 in the laminate S100 may be cut and then pressurized by the second sheet producing unit 24, or the folded-back portions of the first sheet S1 may be cut after being pressurized by the second sheet producing unit 24.

[0106] The density ρ1 of the fibers in the first sheet S1 is not particularly limited, but is preferably 0.05 g / cm 3 More than 0.8g / cm 3 It is preferably 0.1 g / cm or less, 3 More than 0.4g / cm 3 It is more preferable that the thickness and density of the second sheet S2 are equal to or less than 1000 MPa. This makes it easier to maintain the thickness and density of the second sheet S2 at desired uniform values.

[0107] Note that "fibers in the first sheet S1" refers to fibers produced by defibrating the raw material and depositing the fibers produced, and does not include the fibrous binder P1. Also, "density ρ1 of fibers in the first sheet S1" is a parameter that indicates the degree of fiber contained in the first sheet S1, and is not related to the void ratio of a single fiber.

[0108] The fiber density ρ1 of the first sheet S1 can be determined by calculating the volume A (cm3) from the measurement results of the length, width, and thickness dimensions of the first sheet S1 in a planar view, calculating the weight B (g) of the first sheet S1, and calculating B / A. The same applies to the second sheet S2.

[0109] The density ρ2 of the fibers in the second sheet S2 is not particularly limited, but is preferably 0.3 g / cm 3 More than 1.0g / cm 3 It is preferably 0.5 g / cm or less. 3 More than 1.0g / cm 3 It is more preferable that the second sheet S2 has a thickness of 1 / 2 mm or less. This makes it possible to more reliably increase the strength of the second sheet S2.

[0110] When the second sheet S2 is used as a sound absorbing material or a heat insulating material, the density ρ2 of the fibers in the second sheet S2 is 0.05 g / cm 3 More than 0.4g / cm 3 Preferably, it is 0.13 g / cm or less. 3 More than 0.3g / cm 3 More preferably, it is:

[0111] Although ρ1 / ρ2 is not particularly limited, it is preferably 0.1 or more and 0.8 or less, and more preferably 0.15 or more and 0.7 or less, for example. This makes it easier to maintain the thickness and density of the second sheet S2 at desired uniform values, and also makes it possible to obtain a second sheet S2 with sufficient strength.

[0112] As described above, when the density of the fibers in the first sheet S1 is ρ1 and the density of the fibers in the second sheet S2 is ρ2, it is preferable that ρ1 / ρ2 be 0.1 or more and 0.8 or less. This makes it easier to maintain the thickness and density of the second sheet S2 at desired uniform values, and also makes it possible to obtain a second sheet S2 with sufficient strength.

[0113] When both the above-mentioned conditions of ρ0 / ρ1 and ρ1 / ρ2 are satisfied, the synergistic effect of both can produce a second sheet S2 of even higher quality.

[0114] 2, the sheet manufacturing apparatus 100 includes a detection unit 25 that detects the thickness or weight of the second web M8, and a setting unit 26. Based on the detection value of the detection unit 25, the setting unit 26 sets the number of first sheets S1 to be stacked in the laminate S100, thereby obtaining a second sheet S2 of a desired thickness or weight.

[0115] In this embodiment, the detection unit 25 is configured as a weight sensor that detects the weight of the second web M8. However, the configuration is not limited to this, and the detection unit 25 may also detect the thickness of the second web M8. In this case, the detection method is not particularly limited, and may be optical, magnetic, capacitance, contact, or the like.

[0116] The detection unit 25 may also be capable of detecting one or both of the weight and thickness of the second web M8. Furthermore, the detection unit 25 may also be capable of detecting a physical quantity other than the weight and thickness of the second web M8.

[0117] The detection unit 25 is electrically connected to the control unit 281, and the detection value of the detection unit 25 is transmitted as an electric signal to the control unit 281. The control unit 281 calculates the weight per unit area of ​​the second web M8 based on a calculation formula or a table stored in the storage unit 282.

[0118] The control unit 281 also determines the number of first sheets S1 to be stacked in the laminate S100 based on the calculated weight per unit area of ​​the second web M8. For example, a calibration curve or table showing the relationship between the weight per unit area of ​​the second web M8 and the number of first sheets S1 is created in advance and stored in the storage unit 282, and the number of first sheets S1 to be stacked in the laminate S100 can be determined based on this calibration curve or table. The calibration curve or table is also stored in the storage unit 282 according to the thickness and weight of the second sheet S2 set by the user, and the number of first sheets S1 to be stacked in the laminate S100 can be determined taking into account the weight per unit area of ​​the second web M8 according to the thickness and weight of the second sheet S2 set by the user.

[0119] The thickness and weight of the second sheet S2 are set by the user using an information input device (not shown). Information about the thickness or weight of the second sheet S2 input by the user using the information input device is stored in the storage unit 282.

[0120] The setting unit 26 is composed of a processor in the control unit 281 that performs the above calculations and a processor that determines the number of first sheets S1 stacked in the stack S100. The number of first sheets S1 stacked that is set by the setting unit 26 is referred to as the set number.

[0121] The sheet manufacturing apparatus 100 also has an encoder 235A that detects the rotation speed of the feed roller 231A. The encoder 235A detects the rotation speed of the feed roller 231A and transmits the detected encoder value as an electrical signal to the control unit 281. The control unit 281 counts the number of first sheets S1 fed by the feed roller 231A based on the received encoder value. When the counted number of first sheets S1 reaches the set number, the control unit 281 drives the moving mechanism 242B to apply heat and pressure to produce the second sheet S2. In this way, the thickness, density, etc. of the second sheet S2 can be set to desired values, i.e., values ​​set by the user, and the second sheet S2 can be produced under these conditions.

[0122] As described above, the sheet manufacturing apparatus 100 includes a stock section 22 that stores the first sheets S1 cut by the cutting section 21, a supply section 23 that supplies the first sheets from the stock section 22 to the second sheet generating section 24, and a setting section 26 that sets the number of first sheets S1 that will constitute the laminate S100 that will be pressed in the second sheet generating section 24. This allows the second sheet S2 to be produced with the thickness, density, etc. of the second sheet S2 set to desired values, i.e., values ​​set by the user.

[0123] The setting unit 26 may be provided separately from the control unit 281 or the control device 28.

[0124] Furthermore, the setting unit 26 may be omitted, and the user may set and execute the number of first sheets S1 to be stacked in the stack S100.

[0125] The sheet manufacturing apparatus 100 includes a detection unit 25 that detects the thickness or weight of the second web M8 as a web, and a setting unit 26 sets the number of first sheets S1 that constitute the laminate S100 based on the detected value of the detection unit 25. This allows the number of first sheets S1 that constitute the laminate S100 to be set more accurately. Therefore, the second sheet S2 can be produced with the thickness and density of the second sheet S2 set to the desired values, i.e., the values ​​set by the user.

[0126] The second sheet S2 may be produced so that its thickness, weight, density, etc. are set to desired values, i.e., target values, by adjusting the number of first sheets S1 stacked in the laminate S100.

[0127] That is, the setting unit 26 sets the number of first sheets S1 in the stack S100 so that the thickness or weight of the second sheet S2 is a target value, thereby making it possible to easily generate a second sheet S2 having a desired configuration and desired properties.

[0128] The setting unit 26 is not limited to the above configuration, and may be configured to adjust the heating temperature, pressure, and time of application of pressure in the heating and pressurizing blocks 241A and 241B of the second-sheet generating unit 24 in addition to setting the number of first sheets S1 to be stacked in the stack S100. In this case, the setting unit 26 can automatically set the optimum heating temperature and pressure depending on the set number of first sheets S1. For example, if the set number is classified into three levels, large, medium, and small, the larger the set number, the higher the setting of at least one of the heating temperature and pressure.

[0129] In addition, the setting unit 26 may be configured to adjust the heating temperature, pressure, and time in the heating and pressurizing blocks 241A, 241B of the second sheet generating unit 24 instead of setting the set number, i.e., the number of first sheets S1 to be stacked in the stack S100.

[0130] While the sheet manufacturing apparatus of the present invention has been described above with reference to the illustrated embodiment, the present invention is not limited thereto, and each component of the sheet manufacturing apparatus may be replaced with any component that can perform the same function. In addition, any component may be added to the sheet manufacturing apparatus.

[0131] In addition, the raw material supply unit 11 and the crushing unit 12 may be omitted from the sheet manufacturing apparatus. [Explanation of symbols]

[0132] 11...raw material supply section, 12...coarse crushing section, 13...defibration device, 14...sorting section, 15...first web generating section, 16...segmenting section, 17...mixing section, 18...dispersing section, 19...second web generating section, 20...first sheet generating section, 21...cutting section, 22...stock section, 23...supply section, 24...second sheet generating section, 25...detection section, 26...setting section, 27...recovery section, 28...control device, 100...sheet manufacturing device, 121...coarse crushing blade, 122...chute, 141...drum section, 142...housing 151...mesh belt, 152...tension roller, 153...suction part, 161...propeller, 162...housing part, 170...housing part, 171...additive supply part, 172...pipe, 173...blower, 174...screw feeder, 181...drum, 182...housing, 191...mesh belt, 192...tension roller, 193...suction part, 201...first pressure part, 201A...core material, 202...first heating part, 202A...coating layer, 203...curren roller, 204...heating roller, 211...first cutter, 212...second cutter, 231...humidifying section, 231A...feed roller, 232...humidifying section, 232A...conveyor roller, 233...humidifying section, 233A...motor, 234...humidifying section, 234A...motor, 235...humidifying section, 235A...encoder, 236...humidifying section, 241...pipe, 241A...heating and pressurizing block, 241B...heating and pressurizing block, 242...pipe, 242B...moving mechanism, 243 ...pipe, 243A...heater, 243B...heater, 244...pipe, 245...pipe, 246...pipe, 261...blower, 262...blower, 263...blower, 281...control unit, 282...storage unit, 283...communication unit, M1...raw material, M2...coarsely crushed pieces, M3...defibrated material, M4-1...first sorted material, M4-2...second sorted material, M5...first web, M6...fine fragments, M7...mixture, M8...second web, P1...binder, S1...first sheet, S100...laminated body, S2...second sheet

Claims

1. a web generating unit that deposits a fiber-containing raw material to generate a web; a first sheet generating unit that pressurizes the web generated by the web generating unit to generate a first sheet; A sheet manufacturing apparatus characterized by comprising: a second sheet generating unit that pressurizes a stack of multiple first sheets generated by the first sheet generating unit in the thickness direction of the first sheets to generate second sheets.

2. The web includes a binder that binds the fibers together, the first sheet generating unit heats and presses the web, The sheet manufacturing apparatus according to claim 1 , wherein the second sheet generating unit heats and presses the first sheet.

3. The sheet manufacturing apparatus according to claim 2 , wherein the binder has a core material made of a first resin and a coating layer made of a second resin having a melting point lower than that of the first resin, the coating layer covering the core material.

4. 4. The sheet manufacturing apparatus according to claim 1, wherein when the density of the fibers in the first sheet is ρ1 and the density of the fibers in the second sheet is ρ2, ρ1 / ρ2 is 0.1 or more and 0.8 or less.

5. a cutting unit that cuts the first sheet generated by the first sheet generating unit into a predetermined shape, The sheet manufacturing apparatus according to claim 1 , wherein the laminate is formed by stacking a plurality of the first sheets cut by the cutting unit.

6. a stock unit that stores the first sheet cut by the cutting unit; a supply unit that supplies the first sheet from the stock unit to the second sheet generation unit; The sheet manufacturing apparatus according to claim 5 , further comprising: a setting unit that sets the number of the first sheets that constitute the laminate that is pressed by the second sheet generating unit.

7. a detection unit for detecting a thickness or weight of the web; The sheet manufacturing apparatus according to claim 6 , wherein the supply unit sets the number of the first sheets that constitute the stack based on a detection value of the detection unit.

8. The sheet manufacturing apparatus according to claim 7 , wherein the setting unit sets the number of the first sheets constituting the laminate so that the thickness or weight of the second sheet is a target value.

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