JP2016112828A - Sheet-producing apparatus and sheet-producing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control the amount of additive supplied, so that it is made appropriate, based on the amount of fiber transported.SOLUTION: A sheet-producing apparatus includes: a defibrating unit for defibrating a raw material that contains fiber; an additive-supplying unit for supplying an additive to at least part of a defibrated material after defibration by the defibrating unit, wherein the additive comprises a resin for bonding the fibers to each other; and a forming unit for forming a sheet by using a mixture obtained by mixing the at least part of the defibrated material with the additive. The amount of additive supplied when a flow rate of the at least part of the defibrated material or the mixture is large is made larger than that when the flow rate thereof is small, at start up when the sheet-producing apparatus starts forming a sheet or at the end when the apparatus stops forming the sheet.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a sheet manufacturing apparatus and a sheet manufacturing method.

  2. Description of the Related Art Conventionally, a paper recycling apparatus that manufactures recycled paper by depositing a material containing fibers on a mesh belt through a forming drum and passing the deposited material through a pair of heater rollers is known (for example, Patent Documents). 1).

JP 2012-144819 A

  By the way, in the said apparatus, since the intensity | strength of a recycled paper is hard to be obtained, it is necessary to supply the additive etc. which bind | conclude fibers before making it pass through a heater roller. In this case, if the amount of the additive supplied to the material containing the fiber is too large, the texture of the recycled paper is impaired. Therefore, it is desirable to set the amount of the additive according to the amount of the fiber. However, since the amount of fibers flowing through the entire apparatus varies, it is difficult to keep the amount of additive supplied to the fibers constant. In particular, there is a problem that the flow rate of the fiber is large and the setting of an appropriate amount of the additive is difficult at the time of starting to make the recycled paper or at the time of ending when the material is almost exhausted.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

  [Application Example 1] In the sheet manufacturing apparatus according to this application example, the fibers are disposed on at least a part of a defibrating unit for defibrating a material containing fibers and a defibrated material that has been defibrated by the defibrating unit. Sheet supply apparatus comprising: an additive supply unit that supplies an additive containing a resin that binds the resin; and a molding unit that forms a sheet using a mixture obtained by adding the additive to at least a part of the defibrated material. And at the time of starting to start forming the sheet by the sheet manufacturing apparatus or at the end before stopping the forming of the sheet, it is less when the flow rate of at least a part of the defibrated material or the mixture is large. The supply amount of the additive is increased more than the case.

  According to this configuration, at the time of starting to start forming the sheet or at the end before stopping the forming of the sheet, the amount of the conveyed fiber varies, but the supply amount of the additive is controlled according to the amount of the fiber. . Thereby, the sheet | seat with stable quality can be manufactured.

  Application Example 2 The sheet manufacturing apparatus according to the application example includes a removing unit that removes at least a part of the defibrated material, and the defibrated material downstream of the removing unit in the conveyance direction of the defibrated material. The flow rate of at least a part of the mixture or the mixture is detected.

  According to this configuration, it is possible to accurately grasp the flow rate of the defibrated material or the mixture after at least a part of the defibrated material is removed.

  Application Example 3 The sheet manufacturing apparatus according to the application example described above includes a detection unit that detects the flow rate of the mixture.

  According to this configuration, since the density of the defibrated material is small, it is difficult to measure the flow rate, but since the mixture after the additive is added to the defibrated material has a higher density, it is possible to accurately measure the flow rate. it can.

  Application Example 4 The sheet manufacturing apparatus according to the application example described above includes a detection unit that detects a flow rate of at least a part of the defibrated material.

  According to this configuration, the flow rate of the defibrated material to which the additive is added can be known before the additive is added.

  Application Example 5 The sheet manufacturing apparatus according to the application example includes a conveyance path that conveys at least a part of the defibrated material and the mixture, and the conveyance path is bent so that a part of the conveyance path is bent. A detection unit that detects a flow rate of at least a part of the defibrated material or the mixture in a conveying path downstream from the bent portion in the conveying direction of the defibrated material. It is characterized by.

  According to this configuration, the conveying path is provided with a bending portion, and the detection of detecting the flow rate of at least a part of the defibrated material or the mixture in the bending portion or the conveying path downstream of the bending portion in the material conveying direction. Is provided. This conveyance path conveys the defibrated material (or mixture) in the air by, for example, air current or gravity. The defibrated material to be transported is transported while being offset toward one side of the transport path by centrifugal force in the transport path downstream of the bent portion in the transport direction of the bent portion or defibrated material. For this reason, the presence / absence state of the defibrated material or the like can be easily detected by the detection unit. For example, the flow rate of the defibrated material or the like can be easily managed based on the detection.

  Application Example 6 In the sheet manufacturing method according to this application example, an additive containing a resin that defibrates a material containing fibers and binds the fibers to at least a part of the defibrated material. A sheet manufacturing method for forming a sheet using a mixture obtained by adding the additive to at least a part of the defibrated material, at the start of forming the sheet or before stopping the forming of the sheet At the end of the step, at least a part of the defibrated material or the flow rate of the mixture is larger than when the flow rate of the mixture is small.

  According to this configuration, at the time of starting to start forming the sheet or at the end before stopping the forming of the sheet, the amount of the conveyed fiber varies, but the supply amount of the additive is controlled according to the amount of the fiber. . Thereby, the sheet | seat with stable quality can be manufactured.

Schematic which shows the structure of the sheet manufacturing apparatus concerning 1st Embodiment. Schematic which shows the structure of the detection part concerning 1st Embodiment, and its peripheral part. Schematic which shows the structure of the detection part concerning 2nd Embodiment, and its peripheral part. Schematic which shows the structure of the detection part concerning the modification 1, and its peripheral part. Schematic which shows the structure of the detection part concerning the modification 2, and its peripheral part. Schematic which shows the structure of the detection part concerning the modification 3, and its periphery part. Schematic which shows the structure of the detection part concerning the modification 4, and its periphery part.

  Hereinafter, first and second embodiments of the present invention will be described with reference to the drawings. In the following drawings, the scale of each member or the like is shown differently from the actual scale so as to make each member or the like recognizable.

(First embodiment)
First, the configuration of the sheet manufacturing apparatus will be described. The sheet manufacturing apparatus is based on a technology for forming a raw material (defibrated material) Pu such as a pure pulp sheet or used paper on a new sheet Pr, for example. The sheet manufacturing apparatus according to the present embodiment includes a defibrating unit that defibrates a material containing fibers, and a resin that binds the fibers to at least a part of the defibrated material that has been defibrated by the defibrating unit. A sheet manufacturing apparatus comprising: an additive supply unit that supplies an additive; and a molding unit that forms a sheet using a mixture in which the additive is added to at least a part of the defibrated material. At the time of starting to start molding, or at the end before stopping the molding of the sheet, at least a part of the defibrated material or the flow rate of the mixture is larger when the flow rate of the additive is larger than when it is small . Further, the sheet manufacturing method according to the present embodiment defibrates a material containing fibers, and supplies an additive containing a resin that binds the fibers to at least a part of the defibrated material, A sheet manufacturing method for forming a sheet using a mixture in which an additive is added to at least a part of the defibrated material, at the start of forming the sheet or at the end before stopping the forming of the sheet When the flow rate of at least a part of the mixture or the mixture is large, the supply amount of the additive is increased as compared with the case where the flow rate is small. Hereinafter, the configuration of the sheet manufacturing apparatus will be specifically described.

  FIG. 1 is a schematic diagram illustrating a configuration of a sheet manufacturing apparatus according to the present embodiment. As shown in FIG. 1, the sheet manufacturing apparatus 1 of the present embodiment includes a supply unit 10, a crushing unit 20, a defibrating unit 30, a classification unit 40, a sorting unit 50, and an additive supply unit 60. The molding unit 100 and the detection unit 300 are provided. Moreover, the control part 2 which controls these members is provided.

  The supply unit 10 supplies waste paper Pu or the like as a raw material to the crushing unit 20. The supply unit 10 includes, for example, a tray 11 that accumulates and stores a plurality of used paper Pu, and an automatic feeding mechanism 12 that can continuously input the used paper Pu in the tray 11 to the crushing unit 20. The used paper Pu supplied to the sheet manufacturing apparatus 1 is, for example, A4 size paper that is currently mainstream in offices.

  The crushing unit 20 cuts the supplied used paper Pu into pieces of several centimeters square. The crushing unit 20 includes a crushing blade 21 and constitutes an apparatus in which the cutting width of a normal shredder blade is widened. Thereby, the supplied used paper Pu can be easily cut into pieces of paper. The divided rough crushed paper is supplied to the defibrating unit 30 via the conveyance path 201.

  The defibrating unit 30 defibrates a material containing fibers in the air. Specifically, the defibrating unit 30 includes a rotating blade (not shown) that rotates, and performs defibrating to loosen the crushed paper supplied from the crushing unit 20 into fibers. In this application, what is defibrated by the defibrating unit 30 is referred to as a defibrated material, and what has passed through the defibrating unit 30 is referred to as a defibrated material. In addition, the defibrating unit 30 of the present embodiment performs defibrating in a dry manner in the air. As a result of the defibrating process of the defibrating unit 30, the printed ink, toner, and the material applied to the paper such as the anti-bleeding material become fibers of several tens of μm or less (hereinafter referred to as “ink particles”). And separate. Therefore, the defibrated material that comes out from the defibrating unit 30 is fibers and ink particles obtained by defibrating a piece of paper. Then, the airflow is generated by the rotation of the rotary blade, and the fibers defibrated via the transport path 202 are carried on the airflow and conveyed to the classification unit 40 in the air. In addition, you may provide separately the airflow generation apparatus which produces | generates the airflow for making the defibrating part 30 convey the fiber disentangled via the conveyance path 202 to the classification part 40 as needed.

  The classifying unit 40 classifies the introduced material by airflow. In this embodiment, the defibrated material as the introduced material is classified into ink particles and fibers. For example, the classifying unit 40 can classify the conveyed fibers into ink particles and fibers (defibrated material) by applying a cyclone. Note that other types of airflow classifiers may be used instead of the cyclone. In this case, as an airflow classifier other than the cyclone, for example, an elbow jet or an eddy classifier is used. The airflow classifier generates a swirling airflow, which is separated and classified by the difference in centrifugal force received depending on the size and density of the defibrated material, and the classification point can be adjusted by adjusting the speed and centrifugal force of the airflow. . As a result, the ink particles can be divided into relatively small and low density ink particles and fibers larger than the ink particles and high density.

  The classifying unit 40 of the present embodiment is a tangential input type cyclone, and includes an introduction port 40a into which an introduced material is introduced from the defibrating unit 30, a cylinder portion 41 with the introduction port 40a attached in a tangential direction, and a lower portion of the cylinder portion 41. The conical part 42 that follows, the lower outlet 40b provided at the lower part of the conical part 42, and the upper exhaust port 40c for discharging fine powder provided at the upper center of the cylindrical part 41 are configured. The diameter of the conical portion 42 decreases toward the lower side in the vertical direction.

  In the classification process, the airflow on which the defibrated material introduced from the introduction port 40a of the classification unit 40 is changed into a circumferential motion by the cylindrical part 41 and the conical part 42, and is subjected to centrifugal force and classified. Then, the fibers larger than the ink particles and having a high density move to the lower outlet 40b, and the relatively small and low density ink particles are led to the upper exhaust port 40c as fine powder together with air. Then, ink particles are discharged from the upper exhaust port 40 c of the classification unit 40. Then, the discharged ink particles are collected in the receiving unit 80 via the conveyance path 206 connected to the upper exhaust port 40c of the classifying unit 40. On the other hand, a classified product containing fibers classified through the conveyance path 203 from the lower outlet 40 b of the classification unit 40 is conveyed in the air toward the sorting unit 50. From the classification unit 40 to the sorting unit 50, it may be transported by an air current when it is classified, or may be transported from the classification unit 40 located above to the sorting unit 50 located below by gravity. In addition, you may arrange | position the suction part etc. for sucking a short fiber mixture from the upper exhaust port 40c efficiently in the upper exhaust port 40c, the conveyance path 206, etc. of the classification part 40. FIG. Classification is not exactly divided at a certain size or density. Further, it is not exactly divided into fibers and ink particles. Among the fibers, relatively short fibers are discharged from the upper exhaust port 40c together with the ink particles. A relatively large ink particle is discharged from the lower outlet 40b together with the fiber.

  The sorting unit 50 sorts the classified product (defibrated material) including the fibers classified by the classifying unit 40 through the sieve unit 51 having a plurality of openings. More specifically, the classified product including the fibers classified by the classifying unit 40 is sorted into a passing material that passes through the opening and a residue that does not pass through the opening. The sorting unit 50 according to the present embodiment includes a mechanism for dispersing the classified material in the air by rotational movement. Then, the passing material that has passed through the opening by sorting by the sorting unit 50 is transported from the passing material transport unit 52 to the deposition unit 70 via the transport path 204. On the other hand, the residue that has not passed through the opening due to the sorting by the sorting unit 50 is returned to the defibrating unit 30 again as the defibrated material via the conveyance path 205. Thereby, the residue is reused (reused) without being discarded.

  The passing material that has passed through the opening by sorting by the sorting unit 50 is conveyed in the air to the molding unit 100 side via the conveyance path 204. The sorting unit 50 is transported to the deposition unit 70 by a blower 190 that generates an airflow. Further, an additive such as a binder resin (for example, a thermoplastic resin or a thermosetting resin) is added to the passing material to be transported between the sorting unit 50 and the deposition unit 70 in the transport path 204. An agent supply unit 60 is provided. In addition to the binder resin, for example, a flame retardant, a whiteness improver, a sheet strength enhancer, a sizing agent, an absorption modifier, a fragrance, a deodorizer, and the like can be added as the additive. These additives are stored in the additive storage unit 61 and are charged from the charging port 62 by a charging mechanism (not shown). And the mixture with which the additive was added to at least one part of the passing material (defibrated material) is conveyed by the blower 190 to the shaping | molding part 100 side. In addition, the shaping | molding part 100 in this embodiment shape | molds the sheet | seat Pr (web W) using the mixture which added the additive to at least one part of the defibrated material (passage | passing material). Specifically, it includes a deposition unit 70, a pressurizing unit 110, a heating and pressurizing unit 120, and the like.

  The depositing unit 70 allows a material containing fibers to be deposited, and deposits at least a part of the defibrated material defibrated by the defibrating unit 30 in the air. Specifically, the depositing unit 70 forms a web W by depositing using a material containing fibers and a binder resin introduced from the conveyance path 204, and a mechanism for uniformly dispersing the fibers in the air. It has. Further, the depositing unit 70 has a moving unit that deposits the defibrated material as a deposit (web W) while moving. The moving unit of the present embodiment includes a tension roller 72 and an endless mesh belt 73 on which a mesh stretched by the tension roller 72 is formed. The mesh belt 73 rotates (moves) in one direction when at least one of the stretching rollers 72 rotates. In addition, the web W concerning this embodiment says the structure form of the object containing a fiber and binder resin. Therefore, the web W is indicated even when the form or the like changes when the web is heated, pressurized, cut or conveyed.

  First, as a mechanism for uniformly dispersing the fibers in the air, a forming drum 71 into which the fibers and the binder resin are charged is disposed in the deposition unit 70. Then, by rotating the forming drum 71, the binder resin (additive) can be uniformly mixed in the passing material (fiber). The forming drum 71 is provided with a screen having a plurality of small holes. Then, the forming drum 71 is driven to rotate so that the binder resin (additive) is uniformly mixed in the passing material (fiber), and the fiber and the mixture of the fiber and the binder resin that have passed through the small holes are uniformly mixed in the air. Can be dispersed.

  A mesh belt 73 is disposed below the forming drum 71. In addition, a suction device 75 as a suction unit that generates an airflow directed vertically downward is provided below the forming drum 71 via a mesh belt 73. The suction device 75 can suck the fibers dispersed in the air onto the mesh belt 73.

  The fibers and the like that have passed through the small hole screen of the forming drum 71 are deposited on the mesh belt 73 by the suction force of the suction device 75. At this time, by moving the mesh belt 73 in one direction, it is possible to form a web W that includes fibers and a binder resin and is deposited in a long shape. By continuously dispersing from the forming drum 71 and moving the mesh belt 73, a continuous belt-like web W is formed. The mesh belt 73 may be made of metal, resin, or non-woven fabric, and may be any material as long as fibers can be deposited and an air stream can pass therethrough. Note that if the mesh hole diameter of the mesh belt 73 is too large, fibers enter between the meshes, resulting in unevenness when the web W (sheet) is formed. On the other hand, if the mesh hole diameter is too small, the suction device 75. It is difficult to form a stable airflow. For this reason, it is preferable to adjust the hole diameter of a mesh suitably. The suction device 75 can be configured by forming a sealed box with a window of a desired size opened under the mesh belt 73, and sucking air from other than the window to make the inside of the box have a negative pressure from the outside air.

  The web W formed on the mesh belt 73 is conveyed according to the conveyance direction (arrow in the figure) by the rotational movement of the mesh belt 73. On the upper side of the mesh belt 73, an intermediate conveyance unit 90 as a peeling unit is disposed. The web W is peeled off from the mesh belt 73 by the intermediate conveyance unit 90 and conveyed to the pressure unit 110 side. That is, it has a peeling part (intermediate conveyance part 90) which peels the deposit (web W) from the moving part (mesh belt 73), and the deposit (web W) can be conveyed to the pressurizing part 110 by peeling. . When the deposit (web W) is transported to the pressure unit 110, the deposit (web W) is stripped from the moving unit (mesh belt 73) by the stripping unit (intermediate transport unit 90). The intermediate conveyance unit 90 is configured to be able to convey the web W while sucking the web W vertically upward (the direction in which the web W is separated from the mesh belt 73). The intermediate conveyance unit 90 is disposed vertically apart from the mesh belt 73 (in a direction perpendicular to the surface of the web W), and a part of the intermediate conveyance unit 90 is shifted downstream in the conveyance direction of the web W. Are arranged. The conveyance section of the intermediate conveyance unit 90 is a section from the tension roller 72a on the downstream side of the mesh belt 73 to the pressure unit 110.

  The intermediate transport unit 90 includes a transport belt 91, a plurality of stretching rollers 92, and a suction chamber 93. The conveyor belt 91 is an endless mesh belt on which a mesh stretched by a stretch roller 92 is formed. Then, at least one of the plurality of stretching rollers 92 rotates, so that the conveyor belt 91 rotates (moves) in one direction.

  The suction chamber 93 is disposed inside the transport belt 91, has a hollow box shape having an upper surface and four side surfaces in contact with the upper surface, and a bottom surface (a surface facing the transport belt 91 positioned below). Is open. The suction chamber 93 includes a suction unit that generates an air flow (suction force) in the suction chamber 93. Then, by driving the suction part, the internal space of the suction chamber 93 is sucked and air flows from the bottom surface of the suction chamber 93. As a result, an air flow is generated toward the upper side of the suction chamber 93, and the web W can be sucked from above the web W to adsorb the web W to the conveyance belt 91. The conveyor belt 91 moves (circulates) as the stretching roller 92 rotates, and can convey the web W toward the pressure unit 110. Further, the suction chamber 93 is disposed at a downstream position where the mesh chamber 73 partially overlaps with the suction device 75 when viewed from above, and the web W on the mesh belt 73 is placed in the suction chamber. It can be peeled off from the mesh belt 73 at a position opposite to 93 and attracted to the conveyor belt 91. The tension roller 92 rotates so that the conveyance belt 91 moves at the same speed as the mesh belt 73. If there is a difference in speed between the mesh belt 73 and the conveyor belt 91, the web W can be prevented from being pulled and broken or buckled by setting the same speed.

  A pressurizing unit 110 is disposed on the downstream side of the intermediate conveyance unit 90 in the conveyance direction of the web W. The pressure unit 110 includes a pair of pressure rollers 111 and 112 and pressurizes the web W being conveyed. For example, the pressurizing unit 110 pressurizes the web W so as to have a thickness of about 1/5 to 1/30 of the thickness of the web W formed by the deposition unit 70. Thereby, the strength of the web W can be improved.

  A heating and pressurizing unit 120 is disposed on the downstream side of the pressurizing unit 110 in the conveyance direction of the web W. The heating and pressurizing unit 120 binds fibers contained in the web W via a binder resin. Further, the heat and pressure unit 120 heats and presses the web W to have a thickness of about 1/5 to 1/30 of the thickness of the web W formed by the deposition unit 70. The heating and pressing unit 120 according to the present embodiment includes a pair of heating rollers 121 and 122. A heating member such as a heater is provided at the center of the rotating shaft of the heating rollers 121 and 122, and the web W being conveyed is heated by passing the web W between the pair of heating rollers 121 and 122. Can be pressurized. The web W is heated and pressurized by the pair of heating rollers 121 and 122, so that the binder resin is melted and easily entangled with the fibers, and the fiber interval is shortened and the contact point between the fibers is increased.

  As a cutting unit 130 for cutting the web W, a first cutting unit 130a for cutting the web W in a direction intersecting the web W conveyance direction and the web W conveyance are provided downstream of the heating and pressurizing unit 120 in the conveyance direction. The 2nd cutting part 130b which cut | disconnects the web W along the direction is arrange | positioned. The first cutting unit 130a includes a cutter, and cuts the continuous web W into sheets according to a cutting position set to a predetermined length. The second cutting unit 130b includes a cutter and cuts according to a predetermined cutting position in the conveyance direction of the web W. Thereby, a sheet Pr (web W) having a desired size is formed. The cut sheets Pr are stacked on the stacker 160 or the like. In addition, you may comprise so that the web W may be wound up with a winding roller, without cutting, the web W. As described above, the sheet Pr can be manufactured in the sheet manufacturing apparatus 1.

  In addition, the sheet | seat concerning the said embodiment mainly says what used the thing containing fibers, such as used paper and a pure pulp, as a raw material, and was made into the sheet form. However, the shape is not limited to that, and may be a board shape or a web shape (or a shape having irregularities). The raw material may be plant fibers such as cellulose, chemical fibers such as PET (polyethylene terephthalate) and polyester, and animal fibers such as wool and silk. In the present application, the sheet is divided into paper and non-woven fabric. The paper includes a thin sheet form, and includes recording paper for writing and printing, wallpaper, wrapping paper, colored paper, Kent paper, and the like. Nonwoven fabrics are thicker or lower in strength than paper and include nonwoven fabrics, fiber boards, tissue paper, kitchen paper, cleaners, filters, liquid absorbents, sound absorbers, cushioning materials, mats, and the like.

  In the present embodiment, the used paper mainly refers to printed paper. However, if used as a raw material, it is regarded as used paper regardless of whether it is used.

  Next, the structure of the detection part of a sheet manufacturing apparatus and its peripheral part is demonstrated. 2A and 2B show a configuration of the optical detector and its peripheral part, FIG. 2A is a side cross-sectional view, and FIG. 2B is a cross-sectional view taken along line AA in FIG.

  The sheet manufacturing apparatus 1 has a removing unit (classifying unit 40 or sorting unit 50) that removes at least a part of the defibrated material, and from the removing unit (classifying unit 40 or sorting unit 50) in the conveyance direction of the defibrated material. The flow rate of at least a part of the defibrated material or the mixture is detected downstream. In the present embodiment, the detection unit 300 that detects the flow rate of the mixture (added additive to the defibrated material) is provided downstream of the sorting unit 50 as a removing unit that removes at least a part of the defibrated material. doing. More specifically, the detection unit 300 is disposed between the additive supply unit 60 and the deposition unit 70 and on the downstream side in the conveyance direction of the mixture of the blower 190 (see FIG. 1).

  As shown in FIG. 2A, the conveyance path 204 includes a bent portion 210 (210a, 210b) in which a part of the conveyance path 204 is bent. In the present embodiment, as shown in FIG. 2, the conveyance path 204 has horizontal portions 219 a and 219 b arranged in the horizontal direction on the upstream side in the conveyance direction of the mixture in a cross-sectional view. The bent portions 210a and 210b are connected to the horizontal portions 219a and 219b. And it has the linear part 211 (211a, 211b) connected to the bending part 210 in the downstream of the conveyance direction of the mixture of the bending parts 210a, 210b. The opening angle θ of the straight portions 211a and 211b with respect to the horizontal portions 219a and 219b is not less than 45 degrees and not more than 150 degrees. In this embodiment, the opening angle θ is set to approximately 90 degrees. By configuring the transport path 204 in this way, the mixture transported by the airflow from the blower 190 from the upstream side in the transport direction of the mixture of the bending section 210 is transported by centrifugal force in the transport path 204 downstream of the bending section 210. It can be transported by shifting toward one side of the path 204, that is, a part of the bent portion 210a or the straight portion 211a side.

  Moreover, the detection part 300 which detects the flow volume of a mixture is arrange | positioned in the bending part 210 or the conveyance path 204 downstream from the bending part 210 in the conveyance direction of a defibrated material. In the present embodiment, the detection unit 300 is arranged at a midpoint position of the linear portion 211a after the bent portion 210 of the transport path 204 in the transport direction of the defibrated material (mixture). The detection result is transmitted to the control unit 2 by the detection unit 300. The arrangement position of the detection unit 300 is set such that the distance H from the connecting portion between the straight line portion 211a and the bending unit 210 to the optical axis S of the detection unit 300 is, for example, within nine times the inner diameter of the conveyance path 204. The When the distance H exceeds 9 times, the influence of the centrifugal force is reduced, and the mixture may not be offset on one side of the conveyance path 204 in some cases. By setting the distance H within 9 times, detection can be made at a position where the distance H is shifted to one side with certainty, so that the detection accuracy is improved. The distance H may be within 600 mm. In the present embodiment, the detection unit 300 is disposed at a position corresponding to the straight portions 211 a and 211 b of the conveyance path 204.

  The detection unit 300 includes a light emitting unit 300a that emits light and a light receiving unit 300b that receives the light emitted from the light emitting unit 300a. The light emitting unit 300a and the light receiving unit 300b are arranged via the conveyance path 204 so that the optical axis S between the light emitting unit 300a and the light receiving unit 300b is perpendicular to the linear portions 211a and 211b. The light emitting unit 300a is, for example, an LED (Light Emitting Diode) light emitting element or a laser light emitting element. The detection unit 300 is connected to the control unit 2 and driven and controlled based on a predetermined program. In the present embodiment, the light emitting unit 300a is disposed on the linear portion 211a side, that is, the side on which the mixture is transported away, and the light receiving unit 300b is disposed on the opposite linear portion 211b side. Note that the configuration is not limited thereto, and for example, the light receiving unit 300b may be disposed on the linear portion 211a side, and the light emitting unit 300a may be disposed on the opposite linear portion 211b side.

  Further, at least a part of the transport path 204 and a portion corresponding to the optical axis S in the light emitting unit 300a and the light receiving unit 300b of the detection unit 300 are configured to transmit light. Thereby, the light emitted from the light emitting unit 300a of the detecting unit 300 can be received by the light receiving unit 300b. In the present embodiment, a translucent member 220 having translucency is arranged in a part of the straight portions 211a and 211b of the transport path 204. The translucent member 220 only needs to be provided on the optical axis S in at least the light emitting unit 300a and the light receiving unit 300b, and may be disposed in the entire circumferential direction of the transport path 204, or may be disposed in part. It may be.

  2B, the light emitting unit 300a and the light receiving unit 300b are arranged so that the optical axis S in the light emitting unit 300a and the light receiving unit 300b passes through the inside of the transport path 204. In the present embodiment, the light emitting unit 300a and the light receiving unit 300b are arranged at a position where the optical axis S in the light emitting unit 300a and the light receiving unit 300b passes through a portion where the mixture F is most offset by centrifugal force. When the mixture F is transported in the transport path 204 by the air flow, if there is the mixture F, the mixture F passes through the rightmost part inside the transport path 204 in FIG. Since the optical axis S passes through the portion where the mixture F is offset most, the presence of the mixture F can be detected without fail, and the presence / absence state of the mixture F can be detected with high accuracy.

  Specifically, light is generated from the light emitting unit 300a of the detection unit 300, and the emitted light is received by the light receiving unit 300b. At this time, if the mixture F passes between the light emitting unit 300a and the light receiving unit 300b, the light from the light emitting unit 300a is blocked by the mixture F, and the amount of light received by the light receiving unit 300b decreases. That is, when the amount of light received by the light receiving unit 300b that generates light from the light emitting unit 300a and receives the emitted light is large, the mixture F is not conveyed. On the other hand, when the light from the light emitting unit 300a is blocked by the mixture F and the amount of light received by the light receiving unit 300b is reduced, the mixture F is conveyed. Thereby, the presence or absence state of the mixture F is detectable.

  In addition, the light receiving unit 300b acquires the light from the light emitting unit 300a as a received light amount (analog signal). Then, the amount of analog voltage output based on the amount of received light is sampled by a clock signal having a predetermined period (for example, 10 ms). The control unit 2 can obtain the flow rate (transport weight) of the mixture F according to the sampled analog voltage amount by referring to a table in which the analog voltage amount and the flow rate that are prepared in advance through experiments or the like are associated with each other. That is, by monitoring the analog voltage output from the detection unit 300, the flow rate (transport weight) of the mixture F can be managed.

  And in the sheet manufacturing apparatus 1, it controls so that the supply amount of an additive may be increased by the control part 2 rather than the case where the direction where the flow volume of the mixture F is large is small. Specifically, at the time of starting to start forming the sheet Pr or at the end before stopping the forming of the sheet Pr, the supply amount of the additive is increased as compared with the case where the flow rate of the mixture F is small. More specifically, according to the calculated flow rate of the mixture F, the defibrated material and the additive are added so that the mixing ratio becomes a predetermined ratio (for example, 87% of the defibrated material and 13% of the additive). The amount of the additive supplied from the agent supply unit 60 is controlled. Here, since the control unit 2 knows the supply amount of the additive and can derive the flow rate of the defibrated material from the flow rate of the mixture F, the input amount of the additive can be feedback-controlled. Become.

  As mentioned above, according to the said embodiment, the following effects can be acquired.

  The flow rate of the mixture F flowing through the conveyance path 204 is detected by the detection unit 300, and the amount of the additive supplied to the defibrated material is controlled according to the detected flow rate of the mixture F. Thereby, an appropriate amount of additive is supplied even if the flow rate of the defibrated material varies, particularly at the start of forming the web W (sheet Pr) or at the end before stopping the forming of the web W (sheet Pr). Therefore, the sheet Pr with stable quality can be manufactured.

(Second Embodiment)
Next, a second embodiment will be described. Since the basic configuration of the sheet manufacturing apparatus 1a according to the present embodiment is the same as the configuration of the sheet manufacturing apparatus 1 according to the first embodiment, a description thereof will be omitted, and a description will mainly be given of a configuration different from the configuration of the first embodiment. To do.

  FIG. 3 is a schematic diagram (side sectional view) showing the configuration of the detection unit and its peripheral part according to the present embodiment. As shown in FIG. 3, in the sheet manufacturing apparatus 1a of the present embodiment, the flow rate of at least a part of the defibrated material is detected on the downstream side of the sorting unit 50 as a removing unit that removes at least a part of the defibrated material. A detection unit 301 is included. More specifically, the detection unit 301 is disposed between the selection unit 50 and the additive supply unit 60. In addition, a blower 191 is disposed in the conveyance path 204 between the sorting unit 50 and the detection unit 301.

  As shown in FIG. 3, the conveyance path 204 includes a bent portion 210 (210a, 210b) in which a part of the conveyance path 204 is bent. The configuration of the transport path 204 is the same as that of the first embodiment, and a description thereof will be omitted. And the detection part 301 is arrange | positioned in the middle part of the linear part 211 after the bending part 210 of the conveyance path 204 in the conveyance direction of a defibrated material. The detection result detected by the detection unit 301 is configured to be transmitted to the control unit 2. Note that the arrangement position of the detection unit 301 is the same as that of the first embodiment, and a description thereof will be omitted.

  The detection unit 301 includes a light emitting unit 301a and a light receiving unit 301b, and the light emitting unit 301a and the light receiving unit 301b are arranged so that the optical axis S of the light emitting unit 301a and the light receiving unit 301b passes through the inside of the conveyance path 204. Has been. In addition, since the structure of the detection part 301 is the same as that of the structure of the detection part 300 concerning 1st Embodiment, description is abbreviate | omitted.

  And similarly to 1st Embodiment, the control part 2 can obtain the flow volume (carrying weight) of a defibrated material from the output signal of the detection part 301, and management of the flow volume (carrying weight) of a defibrated material is carried out. It becomes possible.

  In the sheet manufacturing apparatus 1a, the control unit 2 performs control so that the supply amount of the additive is increased as compared with the case where the flow rate of the defibrated material is large. Specifically, at the time of starting to start forming the sheet Pr or at the end before stopping the forming of the sheet Pr, the supply amount of the additive is increased as compared with the case where the flow rate of the defibrated material is small. More specifically, according to the calculated flow rate of the defibrated material, the mixing ratio of the defibrated material and the additive becomes a predetermined ratio (for example, 87% of the defibrated material, 13% of the additive), The amount of additive supplied from the additive supply unit 60 is controlled.

  As mentioned above, according to the said embodiment, the following effects can be acquired.

  The flow rate of the defibrated material flowing through the conveyance path 204 is detected by the detection unit 301, and the amount of additive supplied to the defibrated material is controlled according to the detected flow rate of the defibrated material. Thereby, an appropriate amount of additive is supplied even if the flow rate of the defibrated material varies, particularly at the start of forming the web W (sheet Pr) or at the end before stopping the forming of the web W (sheet Pr). Therefore, the sheet Pr with stable quality can be manufactured.

  The present invention is not limited to the above-described embodiment, and various modifications and improvements can be added to the above-described embodiment. A modification will be described below. Modifications may be combined.

  (Modification 1) FIG. 4 is a schematic diagram showing the configuration of a detection unit and its peripheral part according to Modification 1. As shown in FIG. 4, the detection unit 302 that detects the flow rate of the material such as at least a part of the defibrated material flowing in the conveyance path 204 or a mixture includes a light emitting unit 302 a and a light receiving unit 302 b, and includes a material detection region. You may comprise so that may become wide in a conveyance direction. Specifically, the light emitting unit 302a has a longitudinal surface along the material conveyance direction, and the light receiving unit 302b has a longitudinal surface corresponding to the light emitting unit 302a. With this configuration, the material flowing in the conveyance path 204 can be detected in a certain region, so that the material detection accuracy can be improved.

  (Modification 2) FIG. 5 is a schematic diagram showing the configuration of a detection unit and its peripheral part according to Modification 2. As shown in FIG. 5, the detection unit 303 that detects the flow rate of at least part of the defibrated material flowing in the conveyance path 204 or a material such as a mixture includes a plurality of light emitting units 303 a and light receiving units 303 b. You may comprise so that the detection area | region of a material may become large in a conveyance direction. Specifically, the light emitting unit 303a arranges a plurality of light emitting units 303a along the material conveyance direction. And the light-receiving part 303b is arrange | positioned so as to correspond to each arrange | positioned light-emitting part 303a. Even in this case, since the material flowing in the conveyance path 204 can be detected in a certain region, the detection accuracy of the material can be improved.

  (Modification 3) FIG. 6 is a schematic diagram showing the configuration of a detection unit and its peripheral part according to Modification 3. As shown in FIG. 6, a first detection unit 305 and a second detection unit 306 that detect the flow rate of at least a part of the defibrated material flowing in the conveyance path 204 or a material such as a mixture are provided. The first detection unit 305 has a light emitting unit 305a and a light receiving unit 305b, and the second detection unit 306 has a light emitting unit 306a and a light receiving unit 306b. The first detection unit 305 is disposed near the downstream side of the bending unit 210 in the material conveyance direction, and the second detection unit 306 is disposed on the downstream side of the first detection unit 305 in the material conveyance direction. Here, the amount of light emitted from the light emitting unit 305 a of the first detection unit 305 is different from the amount of light emitted from the light emitting unit 306 a of the second detection unit 306. In the present modification, the light amount of the light emitting unit 305a of the first detection unit 305 is set to be larger than the light amount of the light emitting unit 306a of the second detection unit 306. That is, the amount of light is increased (increased) in the region close to the bent portion 210, and the amount of light is decreased (lowered) in the straight portion 211. Note that the first detection unit 305 and the second detection unit 306 are spaced apart so that the mutual light emission does not interfere with each other. If comprised in this way, in the vicinity of the bending part 210, it will become possible to detect by emitting light with a larger amount of light with respect to a dense material. Further, since the material of the straight portion 211 is thin, it can be detected by emitting light with a smaller amount of light. That is, the dynamic range of the flow rate detection range of the material flowing through the transport path 204 can be set wide, and the detection accuracy of the material can be improved. Note that when the light amounts of the first detection unit 305 and the second detection unit 306 are made different, an optical filter as a light reduction unit may be disposed in the light emitting unit 306a of the second detection unit 306. In this way, even when the light emitting units 305a and 306a having the same performance are used, the light quantity of one light emitting unit 306a can be easily reduced (lowered).

  (Modification 4) FIG. 7 is a schematic diagram showing the configuration of a detection unit and its peripheral part according to Modification 4. In the above-described embodiment, the bending portion 210 of the conveyance path 204 is configured to bend approximately 90 degrees with respect to the horizontal portions 219a and 219b, but is not limited to this configuration. As shown in FIG. 7, a configuration having a depression 292 as a bending portion in the middle of the conveyance path 204 may be used. And the detection part 300 is arrange | positioned in the position corresponding to the hollow part 292. FIG. Even if the cross section of the transport path 204 is reduced in this way, the presence or absence of the material can be detected because the material (at least a part of the defibrated material or a mixture) approaches the depression 292 due to the airflow. That is, even if the centrifugal force is not used, the detection may be performed when the material is brought together.

  (Modification 5) In the above-described embodiment, the conveyance direction of the material (at least a part of the defibrated material or the mixture) in the bending portion 210 of the conveyance path 204 is the opposite direction of the gravity direction via the bending portion 210. It is not limited to this. The conveyance direction of the material in the bending part 210 of the conveyance path 204 may be a gravity direction through the bending part 210. Even if it does in this way, the effect similar to the said effect can be acquired.

  (Modification 6) In the above embodiment, the detection unit 300 is arranged on the downstream side of the selection unit 50 as the removal unit, but the present invention is not limited to this. For example, you may arrange | position the detection part 300 in the downstream of the classification part 40 as a removal part. In this case, the sheet manufacturing apparatus has a configuration in which the sorting unit is omitted. Even if it does in this way, the effect similar to the said effect can be acquired.

  DESCRIPTION OF SYMBOLS 1,1a ... Sheet manufacturing apparatus, 2 ... Control part, 10 ... Supply part, 20 ... Crushing part, 30 ... Defibration part, 40 ... Classification part, 50 ... Sorting part, 60 ... Additive supply part, 70 ... Deposition , 90 ... intermediate conveyance part, 100 ... molding part, 204 ... conveyance path, 210 ... bending part, 211 ... straight line part, 300, 301, 303 ... detection part, 300a, 301a, 302a, 303a, 305a, 306a ... light emission , 300b, 301b, 302b, 303b, 305b, 306b ... light receiving part, 305 ... first detection part, 306 ... second detection part.

Claims (6)

A defibrating unit for defibrating material containing fibers;
An additive supply unit that supplies an additive containing a resin that binds the fibers to at least a part of the defibrated material that has been defibrated in the defibrating unit;
A molding unit that forms a sheet using a mixture obtained by adding the additive to at least a part of the defibrated material, and a sheet manufacturing apparatus comprising:
At the time of starting to start forming the sheet by the sheet manufacturing apparatus or at the end before stopping the forming of the sheet, at least part of the defibrated material or the case where the flow rate of the mixture is larger than the case where the amount is smaller A sheet manufacturing apparatus characterized in that the supply amount of the additive is increased. In the sheet manufacturing apparatus according to claim 1,
A removal unit for removing at least a part of the defibrated material;
A sheet manufacturing apparatus that detects a flow rate of at least a part of the defibrated material or the mixture downstream of the removing unit in the conveyance direction of the defibrated material. In the sheet manufacturing apparatus according to claim 1 or 2,
A sheet manufacturing apparatus comprising a detection unit for detecting a flow rate of the mixture. In the sheet manufacturing apparatus according to claim 1 or 2,
A sheet manufacturing apparatus comprising: a detection unit that detects a flow rate of at least a part of the defibrated material. In the sheet manufacturing apparatus according to claim 1 or 2,
A conveyance path for conveying at least a part of the defibrated material and the mixture;
The transport path includes a bent portion in which a part of the transport path is bent,
In the conveyance direction of the said bending part or the said defibrated material, it has a detection part which detects the flow volume of at least one part of the said defibrated material, or the said mixture in the conveyance path downstream from the said bending part. Sheet manufacturing equipment. Defibrating material containing fiber,
Supplying an additive containing a resin that binds the fibers to at least a part of the defibrated material that has been defibrated;
A sheet manufacturing method for forming a sheet using a mixture obtained by adding the additive to at least a part of the defibrated material,
The supply amount of the additive at the time of starting to start forming the sheet or at the end before stopping the forming of the sheet is less than when the flow rate of at least a part of the defibrated material or the mixture is large The sheet manufacturing method characterized by increasing.

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