Separation device

Abstract

To provide a separation device capable of stabilizing the ability to remove foreign matter.SOLUTION: A separation device includes: a material supply section for supplying a material containing a fiber; a defibrating section for defibrating the material supplied from the material supply section; a separation section including a rotating member which has a first surface and a second surface having a front and back relation, is at least partly formed of a mesh, and is supplied with a defibrated material produced in the defibrating section onto the first surface, a suction section which is provided on the second surface side of the rotating member and sucks the defibrated material through the mesh to remove foreign matter, and a collection section which collects the defibrated material from which the foreign matter on the first surface has been removed; a weight detection section for detecting a weight of the material supplied by the material supply section; and a control section for controlling the operation of the separation section on the basis of a detection result of the weight detection section.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a separation device.

Background Art

[0002] Conventionally, a removal device for removing foreign substances and the like in a supplied material has been known (see, for example, Patent Document 1).

[0003] As shown in FIG. 1 of Patent Document 1, this separation device includes a disk-shaped screen 1, a jet outlet 2 provided on one surface side of the screen 1, a suction port 3 provided on the opposite side of the jet outlet 2 through the screen 1, a jet outlet 4 provided on the other surface side of the screen 1 and at a position different from the suction port 3, and a suction port 5 provided on the opposite side of the jet outlet 4 through the screen 1.

[0004] By supplying the defibrated material onto the screen 1 from the jet outlet 2 and performing suction from the suction port 3, excessively fine defibrated material can be removed. At this time, foreign substances in the defibrated material can also be removed. Further, when the screen 1 rotates, the defibrated material remaining on the screen 1 also moves, and at the moving destination, the defibrated material is separated from the screen 1 by the air ejected from the jet outlet 4, and the separated defibrated material can be recovered by the suction of the suction port 5.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, in the separation apparatus described in Patent Document 1, sufficient research has not been conducted on the operating conditions of the nozzle 2, suction port 3, nozzle 4, and suction port 5. For example, if there are inconsistencies in the supply amount of raw material, there is a risk that the ability to remove foreign matter will be inconsistent. [Means for solving the problem]

[0007] This invention was made to solve the above-mentioned problems and can be realized as follows.

[0008] The separation apparatus of the present invention comprises a material supply unit that supplies a material containing fibers, A defibration unit for defibrating the material supplied from the material supply unit, A separation unit having a first surface and a second surface that are in a front-back relationship, at least a portion of which is made of mesh, and on the first surface the defibrated material generated in the defibration unit is supplied; a suction unit provided on the second surface side of the rotating member, which sucks the defibrated material through the mesh to remove foreign matter; and a recovery unit for recovering the defibrated material from which the foreign matter has been removed on the first surface. A weight detection unit for detecting the weight of the material supplied by the material supply unit, The invention is characterized by comprising a control unit that controls the operation of the separation unit based on the detection result of the weight detection unit. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a schematic side view showing a sheet manufacturing apparatus equipped with a first embodiment of the separation device of the present invention. [Figure 2] Figure 2 is a block diagram of the sheet manufacturing apparatus shown in Figure 1. [Figure 3] Figure 3 is a perspective view of the separation apparatus shown in Figure 1. [Figure 4] Figure 4 is a plan view of the separation device shown in Figure 3. [Figure 5] Figure 5 is a flowchart illustrating the control operations performed by the control unit shown in Figure 2. [Figure 6]Figure 6 is a flowchart illustrating the control operations performed by the control unit of the first embodiment of the separation device of the present invention. [Modes for carrying out the invention]

[0010] The separation apparatus of the present invention will be described in detail below based on preferred embodiments shown in the accompanying drawings. <First Embodiment> Figure 1 is a schematic side view showing a sheet manufacturing apparatus equipped with a first embodiment of the separation device of the present invention. Figure 2 is a block diagram of the sheet manufacturing apparatus shown in Figure 1. Figure 3 is a perspective view of the separation device shown in Figure 1. Figure 4 is a plan view of the separation device shown in Figure 3. Figure 5 is a flowchart illustrating the control operations performed by the control unit shown in Figure 2.

[0011] For the sake of clarity, in the following explanation, the three mutually orthogonal axes, as shown in Figure 1, will be referred to as the x-axis, y-axis, and z-axis. The xy-plane containing the x and y axes is horizontal, and the z-axis is vertical. The direction indicated by the arrows on each axis will be referred to as "+", and the opposite direction as "-". In addition, the upper side of Figures 1 and 3 may be referred to as "up" or "above", and the lower side as "down" or "below".

[0012] As shown in Figures 1 and 2, the sheet manufacturing apparatus 100 comprises the separation device 1 of the present invention, a mixing unit 17, a loosening unit 18, a web forming unit 19, a sheet forming unit 20, a cutting unit 21, a stock unit 22, and a recovery unit 27. The separation device 1 also comprises a raw material supply unit 11, a coarse crushing unit 12, a defibration unit 13, a separation unit 10, a weight detection unit 8, and a control unit 28. The raw material supply unit 11 and the coarse crushing unit 12 constitute the material supply unit. Furthermore, each part of the separation device 1 is electrically connected to the control unit 28, and its operation is controlled by the control unit 28. In this embodiment, the control unit 28 of the separation device 1 controls each part of the sheet manufacturing apparatus 100, but the apparatus is not limited to this configuration, and the sheet manufacturing apparatus 100 may have a separate control unit that controls parts other than the separation device 1.

[0013] In addition, the sheet manufacturing apparatus 100 includes a humidifying unit 231, a humidifying unit 234, and a humidifying unit 236. Further, the sheet manufacturing apparatus 100 includes a blower 261, a blower 262, a blower 263, and a blower 264. Also, the blowers 261, 262, 263, and 264 can change the air volume by changing the energization conditions.

[0014] In the sheet manufacturing apparatus 100, a raw material supply process, a crushing process, a defibrating process, a separation process, a mixing process, a loosening process, a web forming process, a sheet forming process, and a cutting process are executed in this order.

[0015] Hereinafter, the configuration of each part will be described. The raw material supply unit 11 is a part that performs a raw material supply process of supplying the raw material M1 to the crushing unit 12. As this raw material M1, it is a sheet-like material made of a fiber-containing material. In addition, the form of the raw material M1 is not limited, such as woven fabric, non-woven fabric, etc. Also, the raw material M1 may be, for example, recycled paper obtained by defibrating and recycling waste paper, or Yupo paper (registered trademark) of synthetic paper, or may not be recycled paper. In this embodiment, the raw material M1 is waste paper that has been used or has become unnecessary.

[0016] The crushing unit 12 is a part that performs a crushing process of crushing the raw material M1 supplied from the raw material supply unit 11 in the air such as in the atmosphere. The crushing unit 12 has a pair of crushing blades 121, a chute 122, and a metering supply unit 123.

[0017] The pair of crushing blades 121 can crush, that is, cut the raw material M1 between them by rotating in opposite directions to obtain crushed pieces M2. The shape and size of the crushed pieces M2 are preferably suitable for the defibrating process in the defibrating unit 13. For example, it is preferably a small piece with a side length of 100 mm or less, and more preferably a small piece with a side length of 10 mm or more and 70 mm or less.

[0018] <00000The chute 122 is disposed below the pair of crushing blades 121 and, for example, has a funnel shape. Thereby, the chute 122 can receive the crushed pieces M2 that have been crushed by the crushing blades 121 and have fallen down.

[0019] Also, above the chute 122, a humidifying unit 231 is disposed adjacent to the pair of crushing blades 121. The humidifying unit 231 humidifies the crushed pieces M2 in the chute 122. This humidifying unit 231 has a filter (not shown) containing moisture and is composed of a vaporization type or warm air vaporization type humidifier that supplies humidified air with increased humidity to the crushed pieces M2 by passing air through the filter. By supplying the humidified air to the crushed pieces M2, it is possible to suppress the adhesion of the crushed pieces M2 to the chute 122 or the like due to static electricity.

[0020] The chute 122 is connected to the defibrating unit 13 via a pipe 241. The crushed pieces M2 collected in the chute 122 pass through the pipe 241 and are conveyed to the metering supply unit 123.

[0021] 2]The metering supply unit 123 includes, although not shown, a storage unit that temporarily stores the crushed pieces M2, a metering unit that measures the crushed pieces M2 discharged from the storage unit, and a discharge unit that discharges the crushed pieces M2 when the crushed pieces M2 in the metering unit reach the set weight. In the present embodiment, the load cell of the metering unit constitutes the weight detection unit 8. Thus, according to the metering supply unit 123, it is possible to intermittently discharge the set weight and quantitatively send it to the defibrating unit 13.

[0022] As shown in FIG. 2, the weight detection unit 8 is electrically connected to the control unit 28, and information regarding the detection result detected by the weight detection unit is transmitted to the control unit 28 as an electrical signal.

[0023] The defibration section 13 is the part that performs the defibration process in which the coarse fragments M2 are defibrated in the air, that is, in a dry manner. Through the defibration process in this defibration section 13, defibrated material M3 can be produced from the coarse fragments M2. Here, "defibration" means separating the coarse fragments M2, which are made up of multiple fibers bound together, into individual fibers. The separated fibers then become the defibrated material M3. The shape of the defibrated material M3 is linear or strip-like. The defibrated material M3 may also exist in a state where they are intertwined and form clumps, that is, in a state where they form what is called a "clump".

[0024] The defibration section 13, in this embodiment for example, is composed of an impeller mill having a high-speed rotating rotor and a liner located on the outer circumference of the rotor. The coarse fragments M2 that flow into the defibration section 13 are sandwiched between the rotor and the liner and defibrated.

[0025] Furthermore, the defibration unit 13 can generate an airflow, i.e., an air current, from the coarse crushing unit 12 toward the separation device 1, by the rotation of the rotor. This allows the coarse crushed pieces M2 to be drawn into the defibration unit 13 from the pipe 241. After the defibration process, the defibrated material M3 can be sent to the separation device 1 via the pipe 242.

[0026] A blower 261 is installed in the middle of pipe 242. The blower 261 is an airflow generator that generates an airflow directed toward the separation device 1. This facilitates the delivery of the defibrated material M3 to the separation device 1.

[0027] The separation device 1 is a device that sorts the defibrated material M3 according to the length of the fibers and performs a separation process to remove foreign matter from the defibrated material M3. The configuration of this separation device 1 will be described in detail later. By passing through the separation device 1, the defibrated material M3 has foreign matter such as colorants removed and becomes defibrated material M4 that contains fibers longer than a predetermined length, i.e., fibers of a length suitable for sheet manufacturing. This defibrated material M4 is then sent to the mixing section 17 on the downstream side.

[0028] A mixing section 17 is located downstream of the separation device 1. The mixing section 17 is the part that performs the mixing process of mixing the defibrated material M4 and the binder P1. This mixing section 17 has a binder supply section 171, a pipe 172, and a blower 173.

[0029] The pipe 172 connects the second suction section 7 of the separation device 1 to the housing section 182 of the loosening section 18, and is a flow path through which the mixture M7 of the defibrated material M4 and the binder P1 passes.

[0030] A binder supply unit 171 is connected to the middle of the pipe 172. The binder supply unit 171 has a screw feeder 174. By rotating this screw feeder 174, the binder P1 can be supplied to the pipe 172 as a powder or particles. The binder P1 supplied to the pipe 172 is mixed with the defibrated material M4 to form a mixture M7.

[0031] The binder P1 is used to bind the fibers together in a later process. Examples include natural ingredients such as starch, dextrin, glycogen, amylose, hyaluronic acid, kudzu, konjac, potato starch, etherified starch, esterified starch, natural gum glue (etherified tamarind gum, etherified locust bean gum, etherified guar gum, acacia arabic gum), fiber-inducing glue (etherified carboxymethylcellulose, hydroxyethylcellulose), seaweed (sodium alginate, agar), and animal proteins (collagen, gelatin, hydrolyzed collagen, sericin), as well as polyvinyl alcohol, polyacrylic acid, and polyacrylamide. One or more of these can be used in combination, but it is preferable that the binder be a natural ingredient, and more preferably starch. It is also possible 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); acrylic resins such as modified polyolefins and polymethyl methacrylate; polyesters such as polyvinyl chloride, polystyrene, polyethylene terephthalate, and polybutylene terephthalate; polyamides (nylons) such as nylon 6, nylon 46, nylon 66, nylon 610, nylon 612, nylon 11, nylon 12, nylon 6-12, and nylon 6-66; liquid crystal polymers such as polyphenylene ether, polyacetal, polyether, polyphenylene oxide, polyether ether ketone, polycarbonate, polyphenylene sulfide, thermoplastic polyimide, polyetherimide, and aromatic polyester; and various thermoplastic elastomers such as styrene-based, polyolefin-based, polyvinyl chloride-based, polyurethane-based, polyester-based, polyamide-based, polybutadiene-based, trans polyisoprene-based, fluororubber-based, and chlorinated polyethylene-based materials. One or more selected from these can be used in combination. Preferably, polyester or a material containing polyester is used as the thermoplastic resin.

[0032] In addition to the binder P1, the binder supply unit 171 may also supply, for example, a coloring agent for coloring the fibers, an agglomeration inhibitor for suppressing the agglomeration of the fibers and the binder P1, a flame retardant for making the fibers and other materials less flammable, and a paper strength enhancer for increasing the paper strength of the sheet S. Alternatively, these may be pre-mixed into the binder P1 and supplied from the binder supply unit 171.

[0033] Furthermore, a blower 173 is installed in the middle of the pipe 172, downstream of the binder supply section 171. The rotating parts of the blower 173, such as blades, mix the defibrated material M4 and the binder P1. The blower 173 can also generate an airflow directed towards the loosening section 18. This airflow can agitate the defibrated material M4 and the binder P1 within the pipe 172. As a result, the mixture M7 can flow into the loosening section 18 in a state where the defibrated material M4 and the binder P1 are uniformly dispersed. In addition, the defibrated material M4 in the mixture M7 is loosened as it passes through the pipe 172, becoming finer fibers.

[0034] The loosening section 18 is the part that performs a loosening process in which intertwined fibers in the mixture M7 are separated. The loosening section 18 has a drum section 181 and a housing section 182 that houses the drum section 181.

[0035] The drum section 181 is a sieve composed of a cylindrical mesh body that rotates around its central axis. The mixture M7 flows into this drum section 181. As the drum section 181 rotates, fibers and other materials in the mixture M7 that are smaller than the mesh opening can pass through the drum section 181. In the process, the mixture M7 is loosened.

[0036] The housing section 182 is connected to the humidifying section 234. The humidifying section 234 is composed of an evaporative humidifier similar to the humidifying section 231. As a result, humidified air is supplied into the housing section 182. This humidified air humidifies the inside of the housing section 182, thereby suppressing the adhesion of the mixture M7 to the inner wall of the housing section 182 due to electrostatic force.

[0037] Furthermore, the mixture M7 loosened in the drum section 181 disperses into the air and falls toward the web forming section 19 located below the drum section 181. The web forming section 19 is the part that performs the web forming process to form a web M8 from the mixture M7. The web forming section 19 has a mesh belt 191, tension rollers 192, and a suction section 193.

[0038] The mesh belt 191 is an endless belt on which the mixture M7 is deposited. This mesh belt 191 is wrapped around four tension rollers 192. The rotational drive of the tension rollers 192 then conveys the mixture M7 on the mesh belt 191 to the downstream side.

[0039] Furthermore, most of the mixture M7 on the mesh belt 191 is larger than the mesh opening of the mesh belt 191. This restricts the mixture M7 from passing through the mesh belt 191, and thus allows it to accumulate on the mesh belt 191. In addition, as the mixture M7 accumulates on the mesh belt 191, it is transported downstream along with the mesh belt 191, forming a layered web M8.

[0040] The suction unit 193 is a suction mechanism that draws air from below the mesh belt 191. This allows the mixture M7 to be drawn onto the mesh belt 191, thereby promoting the accumulation of the mixture M7 on the mesh belt 191.

[0041] A pipe 246 is connected to the suction unit 193. A blower 264 is installed in the middle of this pipe 246. The operation of this blower 264 generates suction force in the suction unit 193.

[0042] A humidifying unit 236 is located downstream of the loosening unit 18. The humidifying unit 236 is composed of an ultrasonic humidifier. This allows moisture to be supplied to the web M8, thereby adjusting the moisture content of the web M8. This adjustment suppresses the adhesion of the web M8 to the mesh belt 191 due to electrostatic force. As a result, the web M8 is easily detached from the mesh belt 191 at the position where the mesh belt 191 is folded back by the tension roller 192.

[0043] Furthermore, the total amount of moisture added to humidification 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.

[0044] A sheet forming section 20 is located downstream of the web forming section 19. The sheet forming section 20 is the part that performs the sheet forming process, which involves forming a sheet S from the web M8. This sheet forming section 20 has a pressurizing section 201 and a heating section 202.

[0045] The pressurizing section 201 has a pair of calender rollers 203, and can pressurize the web M8 between the calender rollers 203 without heating it. This increases the density of the web M8. Preferably, the degree of heating at this time is such that the binder P1 does not melt. The web M8 is then conveyed toward the heating section 202. One of the pair of calender rollers 203 is a driven roller driven by a motor (not shown), and the other is a driven roller.

[0046] The heating section 202 is used when a thermoplastic resin is used as a binder. The heating section 202 has a pair of heating rollers 204, and can heat and pressurize the web M8 between the heating rollers 204. Due to this heating and pressurizing, the binder P1 melts within the web M8, and the fibers bond together via this molten binder P1. This forms a sheet S. This sheet S is then conveyed toward the cutting section 21. One of the pair of heating rollers 204 is a driven roller driven by a motor (not shown), and the other is a driven roller.

[0047] A cutting section 21 is located downstream of the sheet forming section 20. The cutting section 21 is the part that performs the cutting process for cutting the sheet S. This cutting section 21 has a first cutter 211 and a second cutter 212.

[0048] The first cutter 211 cuts the sheet S in a direction intersecting, and especially perpendicular to, the conveying direction of the sheet S.

[0049] The second cutter 212 is located downstream of the first cutter 211 and cuts the sheet S in a direction parallel to the conveying direction of the sheet S. This cutting removes unnecessary portions from both ends of the sheet S, i.e., the ends in the +y axis direction and the -y axis direction, thereby adjusting the width of the sheet S. The portions that are cut off are called "edges".

[0050] By cutting with the first cutter 211 and the second cutter 212 in this manner, a sheet S of the desired shape and size is obtained. This sheet S is then transported further downstream and stored in the stock section 22.

[0051] Next, we will describe the separation device 1. As shown in Figures 1 to 3, the separation device 1 comprises the aforementioned raw material supply unit 11, a coarse crushing unit 12, a defibration unit 13, a separation unit 10, a weight detection unit 8, and a control unit 28. The separation unit 10 includes a rotating member 3 having a mesh 31, a first ejection unit 4 that ejects and supplies defibrated material M3 onto the mesh 31 together with air, a first suction unit 5 (suction unit) that sucks up a portion of the defibrated material M3 on the mesh 31, a second ejection unit 6 that ejects air onto the defibrated material M4 generated by the suction, a second suction unit 7 that sucks up and recovers the defibrated material M4, and a motor 33. Furthermore, the rotating member 3, the second ejection unit 6, and the second suction unit 7 constitute a recovery unit that recovers the defibrated material M4, which is the material remaining on the first surface 311.

[0052] As shown in Figure 3, the rotating member 3 has a mesh 31 that forms a circle in plan view and a support member 32 that supports the mesh 31.

[0053] The mesh 31 has a first surface 311 and a second surface 312 that are in a front-back relationship. In this embodiment, the first surface 311 is the top surface facing vertically upward, and the second surface 312 is the bottom surface facing vertically downward.

[0054] The mesh 31 can be, for example, a mesh made of linear bodies woven together, or a disc-shaped member with multiple through holes. Of the fibers of the defibrated material M3 supplied onto the first surface 311 of the mesh 31, fibers longer than the mesh opening of the mesh 31 remain on the mesh 31, i.e., accumulate, while fibers shorter than the mesh opening of the mesh 31, and minute foreign matter such as colorants, pass through the mesh 31. By setting the mesh opening of the mesh 31 to a desired size, it is possible to selectively leave behind fibers of a length suitable for sheet manufacturing, for example.

[0055] The support member 32 has the function of supporting the mesh 31 and maintaining the flat shape of the mesh 31. In this embodiment, the support member 32 supports the mesh 31 from the first surface 311 side of the mesh 31. The mesh 31 and the support member 32 are fixed to each other at least in part, and the mesh 31 rotates together with the support member 32 as it rotates due to the operation of the motor 33.

[0056] As shown in Figure 4, the support member 32 includes a ring-shaped frame 321 that supports the edges of the mesh 31, a central support portion 322 that supports the central part of the mesh 31, and a plurality of rod-shaped connecting portions 323 that connect the frame 321 and the central support portion 322.

[0057] In this embodiment, the connecting portion 323 is a straight rod with a rectangular prism-like cross-sectional shape. In other words, the connecting portion 323 is a long member that extends from the center to the outer periphery of the mesh 31. In this embodiment, four connecting portions 323 are provided radially, that is, along the circumferential direction of the mesh 31, at equal intervals. The shape of the connecting portion 323 is not limited to the above configuration, and may be any shape, such as a round rod.

[0058] Such a rotating member 3 is connected to a motor 33, which is a drive unit, and can rotate around a central axis O by the operation of the motor 33. The motor 33 is configured to have a variable rotation speed depending on the energizing conditions, and its operation is controlled by the control unit 28. In this embodiment, the rotating member 3 rotates in the direction of the arrow in Figure 4, that is, clockwise when viewed from the first surface 311 side.

[0059] The first ejection unit 4 is installed on the first surface 311 side of the mesh 31. In this embodiment, as shown in Figure 1, the first ejection unit 4 is installed to the right of the central axis O of the mesh 31 when viewed from the -y axis side toward the +y axis side. The first ejection unit 4 is connected to the downstream end of the pipe 242 and has a first nozzle 41 at a position facing the first surface 311 of the mesh 31. The first ejection unit 4 ejects defibrated material M3 from the first nozzle 41 along with air from above toward the mesh 31, that is, from the first surface 311 side toward the second surface 312, using the airflow generated by the blower 261. This allows defibrated material M3 to be supplied and deposited on the first surface 311 of the mesh 31.

[0060] Furthermore, the first nozzle 41 is positioned at a distance from the first surface 311 of the mesh 31. This allows the defibrated material M4 deposited on the first surface 311 of the mesh 31 to move as the mesh 31 rotates.

[0061] Furthermore, the first nozzle 41 has a shape in which its opening surface extends along the circumferential direction of the mesh 31. That is, in a plan view of its opening surface, the first nozzle 41 has a shape having an arc 411 located towards the center of the mesh 31, an arc 412 located further outward than arc 411, and line segments 413 and 414 connecting the ends of these arcs. Arcs 411 and 412 are along the circumferential direction of the mesh 31, with arc 412 being longer than arc 411. Also, line segments 413 and 414 are arranged in this order from the front in the rotational direction of the mesh 31 and are provided along the radial direction of the mesh 31.

[0062] By supplying the defibrated material M3 from the first nozzle 41 of this shape onto the first surface 311 of the mesh 31, the defibrated material M3 can be supplied and deposited along the rotational direction of the mesh 31.

[0063] The first suction unit 5 is located on the second surface 312 side of the mesh 31 and on the opposite side of the first ejection unit 4 via the mesh 31. The first suction unit 5 has a first suction port 51, and is positioned so that when viewed from the direction of the central axis O of the mesh 31, the first suction port 51 overlaps with the first ejection port 41. The first suction unit 5 is also connected to a blower 262 via a pipe 245, and air can be drawn in from the first suction port 51 when the blower 262 is operated. Furthermore, a recovery unit 27, for example composed of a filter, is provided downstream of the blower 262 on the pipe 245. This allows the first suction unit 5 to capture and recover fibers and foreign matter that it has drawn in.

[0064] Furthermore, the first suction port 51 has a shape in which its opening surface extends along the circumferential direction of the mesh 31. That is, in a plan view of its opening surface, the first suction port 51 has a shape having an arc 511 located towards the center of the mesh 31, an arc 512 located further outward than arc 511, and line segments 513 and 514 connecting the ends of these arcs. Arcs 511 and 512 are along the circumferential direction of the mesh 31, with arc 512 being longer than arc 511. Also, line segments 513 and 514 are arranged in this order from the front in the rotational direction of the mesh 31 and are provided along the radial direction of the mesh 31.

[0065] In other words, the first suction port 51, which is the suction port, has a shape in which the opening width increases from the center of the mesh toward the outer circumference. The defibrated material M3 or defibrated material M4 on the mesh 31 moves faster in the circumferential direction of the mesh 31 as it moves toward the outer circumference of the mesh 31, but with the above configuration, sufficient suction of the defibrated material M3 or defibrated material M4 can be performed even on the outer circumference. In this case, the opening width refers to the length in the direction along the arc 511 or arc 512.

[0066] By sucking the defibrated material M3 from the first suction port 51 of this shape, the defibrated material M3 that has accumulated along the rotational direction of the mesh 31 can be sucked through the mesh 31. Therefore, suction can be performed in accordance with the shape of the accumulated defibrated material M3 on the mesh 31, and foreign matter and short fibers in the defibrated material M3 can be removed evenly.

[0067] The second ejection unit 6 is located on the second surface 312 side of the mesh 31 and at a different position from the first suction unit 5, that is, it is positioned forward of the first suction unit 5 in the rotational direction of the mesh 31. In this embodiment, as shown in Figure 1, the second ejection unit 6 is located to the left of the central axis O of the mesh 31 when viewed from the +y axis side toward the -y axis side. The second ejection unit 6 has a second nozzle 61 at a position facing the second surface 312 of the mesh 31. The second ejection unit 6 is also connected to a blower 263 via a pipe 243, and the operation of the blower 263 generates an airflow, allowing air to be ejected from the second nozzle 61. The second nozzle 61 ejects air from the second surface 312 side of the mesh 31 towards the defibrated material M4 on the first surface 311 through the mesh 31. This allows the defibrated material M4 on the mesh 31 to be separated from the first surface 311 of the mesh 31. This allows for the effective recovery of the defibrated material M4 by suction from the second suction unit 7, which will be described later.

[0068] Furthermore, the second nozzle 61 has a shape in which its opening surface is curved along the circumferential direction of the mesh 31. That is, in a plan view of its opening surface, the second nozzle 61 has a shape having an arc 611 located towards the center of the mesh 31, an arc 612 located further outward than arc 611, and line segments 613 and 614 connecting the ends of these arcs. Arcs 611 and 612 are along the circumferential direction of the mesh 31, with arc 612 being longer than arc 611. Also, line segments 613 and 614 are arranged in this order from the front in the rotational direction of the mesh 31 and are provided along the radial direction of the mesh 31.

[0069] By ejecting air from the second nozzle 61 of this shape toward the defibrated material M4 on the mesh 31, the defibrated material M3 can be peeled off and detached from the mesh 31 along the direction of rotation of the mesh 31.

[0070] The second suction unit 7 is located on the first surface 311 side of the mesh 31 and at a different position from the first ejection unit 4, that is, it is positioned forward of the first ejection unit 4 in the rotational direction of the mesh 31. The second suction unit 7 also has a second suction port 71 facing the first surface 311 of the mesh 31, and is positioned so that the second suction port 71 overlaps with the second ejection port 61 when viewed from the direction of the central axis O of the mesh 31. The second suction unit 7 is also connected to the upstream end of the pipe 172 of the mixing unit 17. Furthermore, an airflow is generated by the operation of a blower 173 installed in the middle of the pipe 172, allowing suction to be performed from the second suction port 71. This allows the defibrated material M4 separated from the mesh 31 by the second ejection unit 6 to be sucked up and collected and sent downstream, i.e., to the mixing unit 17.

[0071] Furthermore, the second suction port 71 is positioned at a distance from the first surface 311 of the mesh 31. This prevents the suction force of the second suction unit 7 from hindering the rotation of the mesh 31, thereby contributing to the smooth rotation of the mesh 31.

[0072] Furthermore, the second suction port 71 has a shape in which its opening surface is curved along the circumferential direction of the mesh 31. That is, in a plan view of its opening surface, the second suction port 71 has a shape having an arc 711 located towards the center of the mesh 31, an arc 712 located further outward than arc 711, and line segments 713 and 714 connecting the ends of these arcs. Arcs 711 and 712 are along the circumferential direction of the mesh 31, with arc 712 being longer than arc 711. Also, line segments 713 and 714 are arranged in this order from the front in the rotational direction of the mesh 31 and are provided along the radial direction of the mesh 31.

[0073] By sucking the defibrated material M4 on the mesh 31 from the second suction port 71 of this shape, the defibrated material M4 can be recovered along the rotational direction of the mesh 31.

[0074] Thus, the second suction unit 7 functions as a recovery suction unit that sucks up and recovers the defibrated material M4, which is the material deposited on the first surface 311 of the mesh 31. By recovering the material by suction, recovery can be performed without contact with the defibrated material M4, thereby reducing damage to the defibrated material M4.

[0075] Through this separation device 1, the defibrated material M3 becomes defibrated material M4 containing fibers of a desired length or longer and free of foreign matter, which is then transported downstream to become a high-quality sheet S.

[0076] The control unit 28 includes a CPU (Central Processing Unit) 281 and a storage unit 282. The CPU 281 can perform various decisions and issue various commands, for example.

[0077] The memory unit 282 stores various programs, such as a program for separating foreign matter and a program for manufacturing sheet S, as well as calibration curves, which will be described later.

[0078] Furthermore, this control unit 28 may be built into the sheet manufacturing apparatus 100, or it may be provided in an external device such as an external computer. In this case, communication between the external device and the sheet manufacturing apparatus 100 may be wireless or wired.

[0079] Furthermore, the CPU 281 and the memory unit 282 may, for example, be integrated and configured as a single unit, or the CPU 281 may be built into the sheet manufacturing apparatus 100 and the memory unit 282 may be provided in an external device such as an external computer, or the memory unit 282 may be built into the sheet manufacturing apparatus 100 and the CPU 281 may be provided in an external device such as an external computer.

[0080] Incidentally, depending on the thickness of the raw material M1 and the set amount of quantitative supply in the crushing section 12, there is a risk that the thickness of the defibrated material M3 deposited on the mesh 31 may be uneven. The thicker the defibrated material M3 on the mesh 31, the more likely it is that the suction by the first suction section 5 will be insufficient. On the other hand, the thinner the defibrated material M3 on the mesh 31, the better the suction by the first suction section 5 can be performed. Thus, the degree of suction on the defibrated material M3 varies depending on the thickness of the defibrated material M3 on the mesh 31, resulting in unevenness in the degree of foreign matter removal. To solve this problem, the control unit 28 performs the following control.

[0081] As shown in Figure 5, in step S101, first, the sheet manufacturing process is started by activating each part of the sheet manufacturing apparatus 100. In the separation apparatus 1, even before the defibrated material M3 is supplied from the first ejection section 4, the mesh 31 is rotated, and the first ejection section 4, the first suction section 5, the second ejection section 6, and the second suction section 7 are activated so that air is ejected or sucked in from their openings.

[0082] In step S102, the weight of the coarsely crushed pieces M2 per unit time is detected in the coarse crushing section 12. That is, the weight of the coarsely crushed pieces M2 supplied to the defibration section 13 per unit time is detected. In this embodiment, as described above, the weight of the coarsely crushed pieces M2 in the quantitative supply section 123 of the coarse crushing section 12 is detected.

[0083] Next, in step S103, the rotation speed of the rotating member 3 is determined, that is, the conditions for energizing the motor connected to the mesh 31 are determined. In this embodiment, the rotation speed of the rotating member 3 is determined based on a calibration curve stored in the memory unit 282. The calibration curve is derived in advance to ensure an appropriate suction time according to the amount of coarse fragments M2 supplied, and shows the relationship between the amount of coarse fragments M2 supplied and the rotation speed of the rotating member 3.

[0084] In step S103, the rotation speed of the mesh 31 is determined based on the weight of the coarse fragments M2 detected in step S102 and the calibration curve described above.

[0085] Furthermore, the method is not limited to a calibration curve; for example, the rotation speed of the mesh 31 may be determined based on a table showing the relationship between the supply amount of coarse fragments M2 and the rotation speed of the mesh 31.

[0086] Next, in step S104, the process is executed. That is, the motor is driven to rotate the mesh 31 at the rotational speed determined in step S103.

[0087] Then, in step S105, it is determined whether or not the program for sheet manufacturing is complete. This determination is made, for example, based on whether or not the number of sheets S manufactured has reached the target number. If it is determined in step S105 that the program is not complete, the process returns to step S102 and the subsequent steps are repeated sequentially.

[0088] Thus, in the separation device 1, the rotation speed of the mesh 31 is adjusted according to the weight of the coarse fragments M2. If the weight of the coarse fragments M2 supplied to the defibration unit 13 per unit time fluctuates, the thickness of the defibrated material M3 supplied onto the mesh 31 will fluctuate, which may cause the suction of the first suction unit 5 to become insufficient or excessive. However, according to the present invention, the rotation speed can be adjusted according to the thickness of the defibrated material M3, and the total suction time can be adjusted. Therefore, the ability to remove foreign matter can be kept as constant as possible regardless of the weight of the coarse fragments M2. As a result, the whiteness of the defibrated material M4, and consequently the whiteness of the manufactured sheet S, can be stabilized.

[0089] As described above, the separation device 1 comprises a raw material supply unit 11 and a coarse crushing unit 12 which are material supply units that supply material containing fibers; a defibration unit 13 which defibrates coarse crushed pieces M2, which is an example of material supplied from the coarse crushing unit 12; a rotating member 3 which has a first surface 311 and a second surface 312 that are in a front-back relationship and at least a part of which is made of mesh 31, and on which defibrated material M3 produced by the defibration unit 13 is supplied; a first suction unit 5 provided on the second surface 312 side of the rotating member 3 which is a suction unit that sucks up the defibrated material M3 through the mesh 31 to remove foreign matter; a second ejection unit 6 and a second suction unit 7 which are an example of a recovery unit that recovers the defibrated material M4 from which foreign matter has been removed on the first surface 311; a separation unit 10 which has a weight detection unit 8 which detects the weight of the coarse crushed pieces M2 supplied by the coarse crushing unit 12; and a control unit 28 which controls the operation of the separation unit 10 based on the detection result of the weight detection unit 8. This makes it possible to keep the foreign matter removal efficiency in the separation section 10 as constant as possible, regardless of the weight of the material supplied to the defibration section 13. Therefore, the whiteness of the defibrated material M4 recovered in the separation section 10, and consequently the whiteness of the manufactured sheet S, can be stabilized.

[0090] Furthermore, the control unit 28 adjusts the rotation speed of the rotating member 3 based on the detection result of the weight detection unit 8. This makes it possible to keep the thickness of the defibrated material M3 on the rotating member 3 as constant as possible with simple control by adjusting the rotation speed of the rotating member 3, thereby stabilizing the foreign matter removal performance.

[0091] Furthermore, the control unit 28 increases the rotation speed of the rotating member 3 as the supply rate of the coarse fragments M2, which is an example of the material, per unit time increases, and decreases the rotation speed of the rotating member 3 as the supply rate of the coarse fragments M2 per unit time decreases. This makes it possible to keep the thickness of the defibrated material M3 on the rotating member 3 as constant as possible, and stabilize the ability to remove foreign matter.

[0092] Furthermore, the control unit 28 has a storage unit 282 that stores a calibration curve showing the relationship between the supply amount of coarse crushed pieces M2, which is an example of a material, and the rotation speed of the rotating member 3. This makes it possible to accurately set the rotation speed of the rotating member 3 according to the supply amount of coarse crushed pieces M2.

[0093] The material supply unit, the crushing unit 12, has a quantitative supply unit 123 that quantitatively supplies the material, the crushed pieces M2, and the weight detection unit 8 is provided in the quantitative supply unit 123. This allows for more accurate detection of the material supplied to the defibration unit 13.

[0094] The configuration is not limited to the above, and the weight detection unit 8 may be located in a place other than the quantitative supply unit 123. For example, the weight detection unit 8 may be located in the raw material supply unit 11 and be configured to detect the weight of the raw material M1.

[0095] <Second Embodiment> Figure 6 is a flowchart illustrating the control operations performed by the control unit of the first embodiment of the separation device of the present invention.

[0096] The following description of a second embodiment of the separation apparatus of the present invention will be made with reference to this figure, focusing on the differences from the previously described embodiment, and omitting explanations of similar matters.

[0097] In this embodiment, only the control of step S103 (step S203) differs from that of the first embodiment; the other steps are the same as in the first embodiment.

[0098] As shown in Figure 6, in step S203, the suction force of the first suction unit 5 is determined, that is, the conditions for energizing the blower 262 are determined. In this embodiment, the suction force of the first suction unit 5 is determined based on a calibration curve stored in the memory unit 282. The calibration curve is derived in advance to ensure an appropriate suction force according to the amount of coarse fragments M2 supplied, and shows the relationship between the amount of coarse fragments M2 supplied and the suction force of the first suction unit 5.

[0099] In step S203, the suction force of the first suction unit 5 is determined based on the weight detected in step S102 and the calibration curve described above.

[0100] Thus, in the separation device 1, the control unit 28 adjusts the suction force of the first suction unit 5, which is the suction unit, based on the detection result of the weight detection unit 8. This makes it possible to keep the thickness of the defibrated material M3 on the rotating member 3 as constant as possible with simple control by adjusting the suction force of the first suction unit 5, thereby stabilizing the ability to remove foreign matter.

[0101] Furthermore, the control unit 28 increases the suction force of the first suction unit 5 as the supply rate of the coarse fragments M2, which is an example of the material, per unit time increases, and decreases the suction force of the first suction unit 5 as the supply rate of the coarse fragments M2 per unit time decreases. This makes it possible to keep the thickness of the defibrated material M3 on the rotating member 3 as constant as possible, and stabilize the ability to remove foreign matter.

[0102] Furthermore, the control unit 28 has a storage unit 282 that stores a calibration curve showing the relationship between the supply amount of coarse fragments M2, which is an example of a material, and the suction force of the first suction unit 5, which is a suction unit. This makes it possible to accurately set the suction force of the first suction unit 5 according to the supply amount of coarse fragments M2.

[0103] Furthermore, in conjunction with the adjustment of the separation conditions as described above, the operating conditions of the second ejection unit 6 and the second suction unit 7, i.e., the recovery conditions, may be controlled to be adjusted.

[0104] Although the separation device of the present invention has been described in the illustrated embodiment, the present invention is not limited thereto, and each part constituting the separation device can be replaced with any configuration that can perform a similar function. Furthermore, any additional components may be added.

[0105] Furthermore, the separation apparatus of the present invention may be a combination of any two or more configurations or features from the above embodiments.

[0106] Furthermore, in each of the above embodiments, the material supply unit was configured to include a raw material supply unit and a coarse crushing unit, but the present invention is not limited thereto, and may, for example, be configured as a cartridge that supplies coarse crushed pieces.

[0107] In the embodiments described above, the rotating member was circular in plan view and rotated around a central axis. However, the present invention is not limited to this configuration. For example, the mesh may be made up of an endless belt and rotate in a circulating manner by being wrapped around multiple rollers.

[0108] Furthermore, in the embodiments described above, the first nozzle, first suction port, second nozzle, and second suction port were described as having a curved shape enclosed by two circular arcs and two straight lines. However, the present invention is not limited to this, and may have any shape, such as a rectangle, polygon, or circle.

[0109] Furthermore, the first nozzle, first suction port, second nozzle, and second suction port may have multiple openings. In this case, it is preferable that the number of openings increases towards the outer periphery of the mesh.

[0110] Furthermore, the shapes of the first nozzle, first suction port, second nozzle, and second suction port are not limited to the illustrated configuration and may be any shape, however, when the opening is divided by an arc passing through the midpoint of the opening surface in the radial direction of the mesh, it is preferable that the outer circumference portion has a larger area than the inner circumference portion. Here, the arc refers to the curvature along the outer edge of the mesh. [Explanation of symbols]

[0111] 100...Sheet manufacturing device, 1...Separation device, 10...Separation section, 3...Rotating member, 31...Mesh, 311...First surface, 312...Second surface, 32...Support member, 321...Frame-shaped body, 322...Central support section, 323...Connecting section, 33...Motor, 4...First ejection section, 41...First ejection port, 411...Arc, 412...Arc, 413...Line segment, 414...Line segment, 5...First suction section, 51...First suction port, 511...Arc, 512...Arc, 513...Line Minutes, 514...line segment, 6...second ejection section, 61...second ejection port, 611...arc, 612...arc, 613...line segment, 614...line segment, 7...second suction section, 71...second suction port, 711...arc, 712...arc, 713...line segment, 714...line segment, 8...weight detection section, 11...raw material supply section, 12...coarse crushing section, 121...coarse crushing blade, 122...chute, 123...quantitative supply section, 13...defibration section, 17...mixing section, 171...binder supply section, 172...tube, 173...Blower, 174...Screw feeder, 18...Loosening section, 181...Drum section, 182...Housing section, 19...Web forming section, 191...Mesh belt, 192...Tensioning roller, 193...Suction section, 20...Sheet forming section, 201...Pressing section, 202...Heating section, 203...Calendar roller, 204...Heating roller, 21...Cutting section, 211...First cutter, 212...Second cutter, 22...Stock 231...Humidifying section, 234...Humidifying section, 236...Humidifying section, 241...Tube, 242...Tube, 243...Tube, 245...Tube, 246...Tube, 261...Blower, 262...Blower, 263...Blower, 264...Blower, 27...Recovery section, 28...Control unit, 281...CPU, 282...Memory unit, M1...Raw material, M2...Coarse fragments, M3...Fibrated material, M4...Fibrated material, M7...Mixture, M8...Web, O...Central axis, S...Sheet, P1...Binding agent

Claims

1. A material supply unit that supplies materials including fibers, A defibration unit for defibrating the material supplied from the material supply unit, A rotating member having a first surface and a second surface that are in a front-back relationship and at least a portion of which is made of mesh; a first ejection part that ejects defibrated material generated in the defibration part onto the first surface; a first suction part provided on the second surface side of the rotating member that sucks the defibrated material through the mesh to remove foreign matter; a second ejection part provided on the second surface side of the rotating member that ejects air toward the defibrated material from which the foreign matter has been removed on the first surface; and a second suction part provided on the first surface side of the rotating member that sucks and collects the defibrated material that has been separated from the mesh by the air ejected from the second ejection part. A weight detection unit for detecting the weight of the material supplied by the material supply unit, The system includes a control unit that controls the operation of the separation unit based on the detection result of the weight detection unit, The separation apparatus is characterized in that the control unit adjusts the rotation speed of the rotating member based on the detection result of the weight detection unit, increasing the rotation speed of the rotating member as the amount of material supplied per unit time increases, and decreasing the rotation speed of the rotating member as the amount of material supplied per unit time decreases.

2. The separation apparatus according to claim 1, wherein the control unit has a storage unit that stores a calibration curve showing the relationship between the amount of material supplied and the rotational speed of the rotating member.

3. A material supply unit that supplies materials including fibers, A defibration unit for defibrating the material supplied from the material supply unit, A separation unit having a first surface and a second surface that are in a front-back relationship, at least a portion of which is made of mesh, and on the first surface the defibrated material generated in the defibrated section is supplied; a suction section provided on the second surface side of the rotating member, which sucks the defibrated material through the mesh to remove foreign matter; and a recovery section for recovering the defibrated material from which the foreign matter has been removed from the first surface. A weight detection unit for detecting the weight of the material supplied by the material supply unit, The system includes a control unit that controls the operation of the separation unit based on the detection result of the weight detection unit, The control unit adjusts the suction force of the suction unit based on the detection result of the weight detection unit, increasing the suction force of the suction unit as the amount of material supplied per unit time increases, and decreasing the suction force of the suction unit as the amount of material supplied per unit time decreases.

4. The separation apparatus according to claim 3, wherein the control unit has a storage unit that stores a calibration curve showing the relationship between the amount of material supplied and the suction force of the suction unit.

5. The material supply unit has a quantitative supply unit that supplies the material quantitatively, The separation apparatus according to any one of claims 1 to 4, wherein the weight detection unit is provided in the quantitative supply unit.

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