Patent Description:
Embodiments of the present disclosure relate to a sheet manufacturing apparatus.

A so-called wet method, which includes processes of putting a raw material that contains fibers into water, defibrating the inputted raw material mainly by means of a mechanical action, and forming the defibrated raw material into reproduced paper, has been used in the field of sheet manufacturing apparatuses. Such a sheet manufacturing apparatus requires a huge amount of water. Therefore, the size of the apparatus is large. Moreover, a lot of labor is needed for maintenance of water processing facilities, and energy needed in a drying process is large.

For the purpose of achieving a reduction in size and saving energy, dry-type sheet manufacturing apparatuses using as little water as possible have been proposed. For example, <CIT> discloses a sheet manufacturing apparatus that forms a web by dry-mixing a defibrated material, which is obtained by defibrating paper by dry defibration without using water, with a binder for bonding fibers in the defibrated material together, then, applying heat and pressure to the web by means of rollers while transporting the web, and, after the heating and pressing, performing cutting to manufacture a sheet having a predetermined size by means Another example of a sheet manufacturing apparatus is disclosed in <CIT> of a cutter.

However, in the sheet manufacturing apparatus disclosed in <CIT>, the workpiece in process is in a form of a single continuous long sheet until it is cut into a separate sheet size by the cutter after having been formed into such an in-process sheet shape by the rollers. For this reason, if transportation abnormality such as jamming occurs, it is difficult to troubleshoot and clear the transportation abnormality.

According to the invention there is provided a sheet manufacturing apparatus as defined by claim <NUM>.

A sheet manufacturing apparatus according to a certain aspect of the present disclosure has the following features. The sheet manufacturing apparatus includes a pressing unit, a separate sheet shaping unit, a transportation unit, and a cutting-off unit. The pressing unit includes a pressing roller that presses a material containing fibers and a binder, which has a function of bonding the fibers together, to form the material into a shape of a continuous sheet. The separate sheet shaping unit cuts the continuous sheet into a shape of a separate sheet. The transportation unit is provided between the pressing roller and the separate sheet shaping unit and transports the continuous sheet formed by the pressing unit to the separate sheet shaping unit. The cutting-off unit is provided between the pressing roller and the transportation unit. When transportation abnormality occurs on the continuous sheet that is being transported, the cutting-off unit cuts off, from the continuous sheet, a part of the continuous sheet where the transportation abnormality occurs.

Based on a certain non-limiting advantageous embodiment illustrated in the accompanying drawings, a sheet manufacturing apparatus according to the present disclosure will now be explained in detail.

<FIG> is a schematic side view of the upstream half of a sheet manufacturing apparatus according to an embodiment of the present disclosure. <FIG> is a schematic side view of the downstream half of a sheet manufacturing apparatus according to an embodiment of the present disclosure. <FIG> is a block diagram of major components of the sheet manufacturing apparatus illustrated in <FIG> and <FIG>. Each of <FIG> is an enlarged view, for explaining operation performed when transportation abnormality occurs, of a section enclosed by a broken-line frame illustrated in <FIG>. <FIG> is a flowchart for explaining control operation performed by a control unit illustrated in <FIG>.

In the description below, in order to facilitate an explanation, three axes orthogonal to one another will be referred to as the x axis, the y axis, and the z axis as shown in <FIG>, <FIG>, and <FIG>. The x-y plane including the x axis and the y axis is horizontal. The z axis is vertical. The direction indicated by the head of an arrow on each axis is denoted as "+". The opposite direction is denoted as "-". An upper position in <FIG>, <FIG>, <FIG> will be referred to as "above/over" or "upper", and a lower position will be referred to as "below/under" or "lower". The left side in <FIG>, <FIG>, <FIG> will be referred to as "upstream", and the right side thereof will be referred to as "downstream".

As illustrated in <FIG> and <FIG>, a sheet manufacturing apparatus <NUM> includes a raw material supplying unit <NUM>, a coarse crushing unit <NUM>, a defibrating unit <NUM>, a screening unit <NUM>, a first web forming unit <NUM>, a fragmenting unit <NUM>, a mixing unit <NUM>, a disentangling unit <NUM>, a second web forming unit <NUM>, a sheet forming unit <NUM>, a separate sheet shaping unit <NUM>, a stock unit <NUM>, a transportation unit <NUM>, a tension adjustment unit <NUM>, a collection unit <NUM>, a control unit <NUM>, a cutting-off unit <NUM>, and an abnormality detection unit <NUM>. Components that constitute the sheet manufacturing apparatus <NUM> are electrically coupled to the control unit <NUM> illustrated in <FIG>. The operation of them is controlled by the control unit <NUM>.

As illustrated in <FIG>, the sheet manufacturing apparatus <NUM> further includes humidifying units <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>. In addition, the sheet manufacturing apparatus <NUM> includes blowers <NUM>, <NUM>, <NUM>, and <NUM>.

In the sheet manufacturing apparatus <NUM>, a raw material supplying process, a coarse crushing process, a defibrating process, a screening process, a first web forming process, a fragmenting process, a mixing process, a disentangling process, a second web forming process, a sheet forming process, and a cutting process are performed in this order.

The structure of each unit will now be explained.

As illustrated in <FIG>, the raw material supplying unit <NUM> is a section that performs a raw material supplying process of supplying a raw material M1 to the coarse crushing unit <NUM>. An example of the raw material M1 is a sheet-like material containing fibers, including cellulose fibers. The cellulose fiber may be any fibrous body containing cellulose as a main compound, and may contain hemicellulose or lignin in addition to cellulose. The form of the raw material M1 is not limited, for example, may be woven fabric or non-woven fabric. The raw material M1 may be, for example, recycled paper reproduced by defibrating used paper or synthetic YUPO paper (registered trademark), or may be non-recycled paper. In the present embodiment, the raw material M1 is waste paper that has been used or is no longer needed.

The coarse crushing unit <NUM> is a section that performs a coarse crushing process of coarsely crushing the raw material M1 supplied from the raw material supplying unit <NUM> in air such as atmospheric conditions. The coarse crushing unit <NUM> includes a pair of coarse crushing blades <NUM> and a chute <NUM>.

By rotating in respective directions that are the opposite of each other, the pair of coarse crushing blades <NUM> is able to coarsely crush, that is, shred, the raw material M1 therebetween into coarse crushed pieces M2. It will be advantageous if the coarse crushed piece M2 has a shape and size suitable for defibration by the defibrating unit <NUM>. For example, preferably, the length of a side of the small piece may be <NUM> or less. More preferably, the length of a side of the small piece may be, for example, <NUM> or more and <NUM> or less.

The chute <NUM> is provided under the pair of coarse crushing blades <NUM> and has a shape like, for example, a funnel. The chute <NUM> is able to receive the coarse crushed pieces M2 coarsely crushed by, and falling from, the coarse crushing blades <NUM>.

The humidifying unit <NUM> is provided next to the pair of coarse crushing blades <NUM> over the chute <NUM>. The humidifying unit <NUM> humidifies the coarse crushed pieces M2 in the chute <NUM>. The humidifying unit <NUM> includes a non-illustrated filter that contains moisture. The humidifying unit <NUM> is a vaporizing humidifier, in particular, a warm-air-vaporization-type humidifier, configured to supply humidified air with increased humidity to the coarse crushed pieces M2 by passing air through the filter. Supplying humidified air to the coarse crushed pieces M2 makes it possible to prevent the static cling of the coarse crushed pieces M2 to the chute <NUM> and the like.

The chute <NUM> is connected to the defibrating unit <NUM> via a pipe <NUM>. The coarse crushed pieces M2 gathered into the chute <NUM> are sent to the defibrating unit <NUM> through the pipe <NUM>.

The defibrating unit <NUM> is a section that performs a defibrating process of defibrating the coarse crushed pieces M2 in air, which means dry defibration. It is possible to produce a defibrated material M3 from the coarse crushed pieces M2 through the defibrating process performed by the defibrating unit <NUM>. The term "defibration" means the disentanglement of the coarse crushed pieces M2 made of plural entangled fibers into individual fibers. The result of the disentanglement is the defibrated material M3. The defibrated material M3 has a string shape or a ribbon shape. The defibrated material M3 may be in a state of so-called "lumps", in which defibrated fibers are intertwined with one another in an agglomerated manner.

The defibrating unit <NUM> is, for example, in the present embodiment, an impeller mill that includes a rotor that rotates at a high speed and a liner that is located at the outer circumference of the rotor, though not illustrated. The coarse crushed pieces M2 that have flowed into the defibrating unit <NUM> go into the gap between the rotor and the liner and are defibrated.

By rotation of the rotor, the defibrating unit <NUM> is able to produce the flow of air, that is, airflow, from the coarse crushing unit <NUM> toward the screening unit <NUM>. The airflow enables the defibrating unit <NUM> to suck the coarse crushed pieces M2 from the pipe <NUM>. After the defibration, it is possible to send the defibrated material M3 to the screening unit <NUM> through a pipe <NUM>.

A blower <NUM> is provided between the ends of the pipe <NUM>. The blower <NUM> is an airflow generator that generates airflow toward the screening unit <NUM>. This promotes the delivery of the defibrated material M3 to the screening unit <NUM>.

The screening unit <NUM> is a section that performs a screening process of screening the defibrated material M3 according to the lengths of fibers. In the screening unit <NUM>, the defibrated material M3 is sorted into a first screened material M4-<NUM> and a second screened material M4-<NUM>, which is larger than the first screened material M4-<NUM>. The first screened material M4-<NUM> has a size suitable for the subsequent manufacture of a sheet S. The average length may be preferably <NUM> or more and <NUM> or less. The second screened material M4-<NUM> contains, for example, insufficiently defibrated fibers, excessive agglomeration of defibrated fibers, and the like.

The screening unit <NUM> has a drum portion <NUM> and a housing portion <NUM>, which houses the drum portion <NUM>.

The drum portion <NUM> is a sieve that has a cylindrical net structure and rotates around its central axis. The defibrated material M3 flows into the drum portion <NUM>. By rotation of the drum portion <NUM>, the defibrated material M3 that is smaller than the mesh of the net is sorted as the first screened material M4-<NUM>, and the defibrated material M3 that is larger than the mesh of the net is sorted as the second screened material M4-<NUM>.

The first screened material M4-<NUM> falls from the drum portion <NUM>.

On the other hand, the second screened material M4-<NUM> is sent to a pipe <NUM> connected to the drum portion <NUM>. The pipe <NUM> is connected to the pipe <NUM> at its end that is the opposite of an end connected to the drum portion <NUM>, that is, at the upstream end. The second screened material M4-<NUM> that has flowed through the pipe <NUM> merges with the coarse crushed pieces M2 inside the pipe <NUM> and flows together with the coarse crushed pieces M2 into the defibrating unit <NUM>. By this means, the second screened material M4-<NUM> is returned to the defibrating unit <NUM> and is subjected to defibration again together with the coarse crushed pieces M2.

The first screened material M4-<NUM> discharged from the drum portion <NUM> falls while being dispersed in air, and travels toward the first web forming unit <NUM>, which is located under the drum portion <NUM>. The first web forming unit <NUM> is a section that performs a first web forming process of forming a first web M5 from the first screened material M4-<NUM>. The first web forming unit <NUM> includes a mesh belt <NUM>, three stretching rollers <NUM>, and a suction unit <NUM>.

The mesh belt <NUM> is an endless belt, and the first screened material M4-<NUM> is deposited thereon. The mesh belt <NUM> is stretched around the three stretching rollers <NUM>. The first screened material M4-<NUM> on the mesh belt <NUM> is transported downstream by the rotation of the stretching rollers <NUM>.

The first screened material M4-<NUM> has a size larger than the mesh of the mesh belt <NUM>. Therefore, the first screened material M4-<NUM> falling down is unable to pass through the mesh belt <NUM> and thus becomes deposited on the mesh belt <NUM>. The first screened material M4-<NUM> is transported downstream together with the mesh belt <NUM> while depositing on the mesh belt <NUM>. Therefore, the first web M5 that has a layer shape is formed.

There is a possibility that the first screened material M4-<NUM> contains foreign particles, for example, dust, or particles like dust. For example, coarse crushing or defibration sometimes produces dust or the like. Dust or the like is collected into the collection unit <NUM> described later.

The suction unit <NUM> is a suction mechanism that sucks air from below the mesh belt <NUM>. By this means, it is possible to suck dust or the like that has passed through the mesh belt <NUM>, together with air.

The suction unit <NUM> is connected to the collection unit <NUM> via a pipe <NUM>. The dust or the like sucked by the suction unit <NUM> is collected into the collection unit <NUM>.

A pipe <NUM> is connected to the collection unit <NUM>. A blower <NUM> is provided between the ends of the pipe <NUM>. By the operation of the blower <NUM>, a suction force can be generated in the suction unit <NUM>. This promotes the forming of the first web M5 on the mesh belt <NUM>. Therefore, the first web M5 is substantially free from dust or the like. Dust or the like flows through the pipe <NUM> to reach the collection unit <NUM> by the operation of the blower <NUM>.

The housing portion <NUM> is connected to the humidifying unit <NUM>. The humidifying unit <NUM> is a vaporizing humidifier, similarly to the humidifying unit <NUM>. Therefore, humidified air is supplied into the housing portion <NUM>. The humidified air humidifies the first screened material M4-<NUM>. This prevents the static cling of the first screened material M4-<NUM> to the inner wall of the housing portion <NUM>.

The humidifying unit <NUM> is provided downstream of the screening unit <NUM>. The humidifying unit <NUM> is an ultrasonic humidifier that sprays water. Ultrasonic spraying supplies moisture to the first web M5, thereby adjusting the moisture content of the first web M5. The moisture adjustment prevents the static cling of the first web M5 to the mesh belt <NUM>. Therefore, the first web M5 comes off easily from the mesh belt <NUM> at a position where the mesh belt <NUM> is turned back by the stretching roller <NUM>.

The fragmenting unit <NUM> is provided downstream of the humidifying unit <NUM>. The fragmenting unit <NUM> is a section that performs a fragmenting process, in which the first web M5 that has come off from the mesh belt <NUM> is fragmented. The fragmenting unit <NUM> includes a propeller <NUM> that is rotatably supported and a housing portion <NUM> that houses the propeller <NUM>. By rotating the propeller <NUM>, it is possible to fragment the first web M5. The first web M5 is broken into fragments M6. The fragments M6 drop inside the housing portion <NUM>.

The housing portion <NUM> is connected to the humidifying unit <NUM>. The humidifying unit <NUM> is a vaporizing humidifier, similarly to the humidifying unit <NUM>. Therefore, humidified air is supplied into the housing portion <NUM>. The humidified air prevents the static cling of the fragments M6 to the propeller <NUM> or the inner wall of the housing portion <NUM>.

The mixing unit <NUM> is provided downstream of the fragmenting unit <NUM>. The mixing unit <NUM> is a section that performs a mixing process of mixing the fragments M6 with a binder P1. The mixing unit <NUM> includes a binder supplying portion <NUM>, a pipe <NUM>, and a blower <NUM>.

The pipe <NUM>, through which a mixture M7 of the fragments M6 and the binder P1 flows, connects the housing portion <NUM> of the fragmenting unit <NUM> and a housing portion <NUM> of the disentangling unit <NUM>.

The binder supplying portion <NUM> is connected between the ends of the pipe <NUM>. The binder supplying portion <NUM> includes a screw feeder <NUM>. By rotation of the screw feeder <NUM>, it is possible to supply the binder P1 that is in the form of powder or particles into the pipe <NUM>. The binder P1 supplied into the pipe <NUM> is mixed with the fragments M6 to turn into the mixture M7.

The binder P1 bonds fibers together in subsequent processes. For example, a thermoplastic resin, a curable resin, starch, dextrin, glycogen, amylose, hyaluronic acid, arrowroot, konjac, dogtooth violet starch, etherified starch, esterified starch, natural gum glue (etherified tamarind gum, etherified locust bean gum, etherified guar gum, acacia arabica gum), fiber induction glue (etherified carboxymethyl cellulose, hydroxyethyl cellulose), seaweed (sodium alginate, agar), animal protein (collagen, gelatin, hydrolyzed collagen, sericin), etc. can be used. A thermoplastic resin, among them, can be preferably used. Examples of the thermoplastic resin include an AS resin, an ABS resin, polyethylene, polypropylene, polyolefin such as an ethylene-vinyl acetate copolymer (EVA), modified polyolefin, an acrylic resin such as polymethyl methacrylate, polyvinyl chloride, polystyrene, polyester such as polyethylene terephthalate and polybutylene terephthalate, polyamide such as nylon <NUM>, nylon <NUM>, nylon <NUM>, nylon <NUM>, nylon <NUM>, nylon <NUM>, nylon <NUM>, nylon <NUM>-<NUM>, and nylon <NUM>-<NUM>, polyphenylene ether, polyacetal, polyether, polyphenylene oxide, polyetheretherketone, polycarbonate, polyphenylene sulfide, thermoplastic polyimide, polyetherimide, a liquid crystal polymer such as aromatic polyester, various thermoplastic elastomers such as a styrene-based thermoplastic elastomer, a polyolefin-based thermoplastic elastomer, a polyvinyl chloride-based thermoplastic elastomer, a polyurethane-based thermoplastic elastomer, a polyester-based thermoplastic elastomer, a polyamide-based thermoplastic elastomer, a polybutadiene-based thermoplastic elastomer, a trans polyisoprene-based thermoplastic elastomer, a fluoro rubber-based thermoplastic elastomer, and a chlorinated polyethylene-based thermoplastic elastomer, and the like. Any one selected from among those enumerated above, or a combination of two or more, may be used. Preferably, for example, polyester or a composition containing polyester can be used as the thermoplastic resin.

A colorant for coloring fibers, an aggregation inhibitor for inhibiting aggregation of fibers or aggregation of the binder P1, a flame retardant for making fibers difficult to burn, a paper strengthening agent for enhancing the strength of a sheet S, and the like, for example, may be included in addition to the binder P1 supplied from the binder supplying portion <NUM>. Alternatively, a composite of the binder P1 containing any of them prepared in advance may be supplied from the binder supplying portion <NUM>.

The blower <NUM> is provided downstream of the binder supplying portion <NUM> between the ends of the pipe <NUM>. The fragments M6 and the binder P1 are mixed with each other by the action of the rotating portion such as blades of the blower <NUM>. The blower <NUM> is able to generate airflow toward the disentangling unit <NUM>. The airflow stirs the fragments M6 and the binder P1 inside the pipe <NUM>. This makes it possible for the mixture M7 to flow into the disentangling unit <NUM> in a state in which the fragments M6 and the binder P1 are uniformly dispersed. The fragments M6 in the mixture M7 are disentangled in the process of flowing through the pipe <NUM>, thereby turning into a finer fibrous form.

The disentangling unit <NUM> is a section that performs a disentangling process of disentangling fibers intertwined with one another in the mixture M7. The disentangling unit <NUM> has a drum portion <NUM> and a housing portion <NUM>, which houses the drum portion <NUM>.

The drum portion <NUM> is a sieve that has a cylindrical net structure and rotates around its central axis. The mixture M7 flows into the drum portion <NUM>. When the drum portion <NUM> rotates, fibers, etc. that are smaller than the mesh of the net, among those contained in the mixture M7, are able to pass through the drum portion <NUM>. In this process, the mixture M7 is disentangled.

The housing portion <NUM> is connected to the humidifying unit <NUM>. The humidifying unit <NUM> is a vaporizing humidifier, similarly to the humidifying unit <NUM>. Therefore, humidified air is supplied into the housing portion <NUM>. The humidified air humidifies the inside of the housing portion <NUM>. This prevents the static cling of the mixture M7 to the inner wall of the housing portion <NUM>.

The mixture M7 disentangled in the drum portion <NUM> falls while being dispersed in air and travels toward the second web forming unit <NUM>, which is located under the drum portion <NUM>. The second web forming unit <NUM> is a section that performs a second web forming process of forming a second web M8 from the mixture M7. The second web forming unit <NUM> includes a mesh belt <NUM>, stretching rollers <NUM>, and a suction unit <NUM>.

The mesh belt <NUM> is an endless belt, and the mixture M7 becomes deposited thereon. The mesh belt <NUM> is stretched around the four stretching rollers <NUM>. The mixture M7 on the mesh belt <NUM> is transported downstream by the rotation of the stretching rollers <NUM>.

The size of most of the mixture M7 on the mesh belt <NUM> is larger than the mesh of the mesh belt <NUM>. Therefore, most of the mixture M7 is unable to pass through the mesh belt <NUM> and thus becomes deposited on the mesh belt <NUM>. The mixture M7 is transported downstream together with the mesh belt <NUM> while depositing on the mesh belt <NUM>. Therefore, the second web M8 that has a layer shape is formed.

The suction unit <NUM> is a suction mechanism that sucks air from below the mesh belt <NUM>. Therefore, it is possible to suck the mixture M7 onto the mesh belt <NUM>, and the deposition of the mixture M7 on the mesh belt <NUM> is promoted.

A pipe <NUM> is connected to the suction unit <NUM>. A blower <NUM> is provided between the ends of the pipe <NUM>. By the operation of the blower <NUM>, a suction force can be generated in the suction unit <NUM>.

The humidifying unit <NUM> is provided downstream of the disentangling unit <NUM>. The humidifying unit <NUM> is an ultrasonic humidifier, similarly to the humidifying unit <NUM>. Ultrasonic spraying supplies moisture to the second web M8, thereby adjusting the moisture content of the second web M8. The moisture adjustment prevents the static cling of the second web M8 to the mesh belt <NUM>. Therefore, the second web M8 comes off easily from the mesh belt <NUM> at a position where the mesh belt <NUM> is turned back by the stretching roller <NUM>.

The total moisture content added to the humidifying units <NUM> to <NUM> may be, for example, <NUM> parts by mass or more and <NUM> parts by mass or less with respect to <NUM> parts by mass of the material before humidification.

As illustrated in <FIG>, the sheet forming unit <NUM> is provided downstream of the second web forming unit <NUM>. The sheet forming unit <NUM> is a section that performs a sheet forming process of forming a continuous sheet S0 from the second web M8. The sheet forming unit <NUM> includes a pressing portion <NUM> and a heating portion <NUM>.

The pressing portion <NUM> includes a pair of pressing rollers <NUM> and is able to press the second web M8 between the pressing rollers <NUM> without substantial heating. This increases the density of the second web M8. For example, the degree of substantial non-heating may be a degree that does not cause the melting of the binder P1. The second web M8 with increased density is transported to the heating portion <NUM>. One of the pair of pressing rollers <NUM> is a master roller that is driven by the operation of a motor that is not illustrated, and the other is a slave roller.

The heating portion <NUM> includes a pair of heating rollers <NUM>. It is possible to apply pressure while heating the second web M8 between the heating rollers <NUM>. The heating and pressing causes the melting of the binder P1 in the second web M8. The molten binder P1 bonds the fibers together. As a result, a single continuous sheet S0 is formed. Then, the continuous sheet S0 is transported toward the separate sheet shaping unit <NUM>. One of the pair of heating rollers <NUM> is a master roller that is driven by the operation of a motor that is not illustrated, and the other is a slave roller.

The pressing portion <NUM> and the heating portion <NUM> described above constitute a group of shaping rollers that process the shape of the web that includes the material containing fibers. The heating portion <NUM> may be omitted. The pressing rollers <NUM> of the pressing portion <NUM> may have a heating function.

The separate sheet shaping unit <NUM> is provided downstream of the sheet forming unit <NUM>. The separate sheet shaping unit <NUM> is a section that performs a cutting process of cutting the continuous sheet S0 into the shape of the sheet S, which is an example of a separate sheet. The separate sheet shaping unit <NUM> includes a first cutter <NUM> and a second cutter <NUM>. The second cutter <NUM> is provided downstream of the first cutter <NUM>.

The first cutter <NUM> cuts the continuous sheet S0 in a direction that intersects with the transport direction of the continuous sheet S0, in particular, a direction that is orthogonal thereto. The first cutter <NUM> includes a pair of rollers 211A and blades 211B. These rollers 211A constituting the pair are provided at a distance from each other in the thickness direction of the sheet S that is being transported, namely, in the z-axis direction. The blade 211B protrudes from the circumferential surface of each of the pair of rollers 211A. The blade 211B is provided in such a way as to extend in the shaft direction of each of the pair of rollers 211A.

As illustrated in <FIG>, the first cutter <NUM> is electrically coupled to the control unit <NUM>. Its operation is controlled by the control unit <NUM>. The first cutter <NUM> rotates in a direction indicated by each arrow thereof in <FIG>. During the rotation, the blades 211B of the first cutter <NUM> come into contact with each other. Due to this blade contact, the continuous sheet S0 passing therebetween is cut. It is possible to adjust the length of the sheet S in the x-axis direction by adjusting the rotation speed of each of the pair of rollers of the first cutter <NUM>.

The second cutter <NUM> cuts the sheet S in a direction parallel to the transport direction of the sheet S downstream of the first cutter <NUM>. The second cutter <NUM> is comprised of four disc-shaped rotary blades 212A and 212B. The rotary blades 212A and the rotary blades 212B are provided opposite to each other such that the sheet S that is being transported is interposed therebetween, that is, with a transportation path <NUM> traversing therebetween. By the contact of the rotary blades 212A and the rotary blades 212B, it is possible to cut the sheet S that is being transported.

The rotary blades 212A and the rotary blades 212B each configured as a lateral pair in the width direction of the sheet S, that is, in the y-axis direction, are disposed. The purpose of cutting in this process is to remove unnecessary edge portions at both ends of the sheet S, that is, its +y directional end and -y directional end, to adjust the width of the sheet S properly. The cut and removed portion is called "waste edge".

In the second cutter <NUM>, the distance between one and the other of the rotary blades 212A spaced from each other in the y-axis direction, and the distance between one and the other of the rotary blades 212B spaced from each other in the y-axis direction, are adjustable. It is possible to adjust the length of the sheet S in the y-axis direction by adjusting this distance.

A sheet S having a desired shape and size can be obtained by cutting with the first cutter <NUM> and the second cutter <NUM> described above. The sheet S is further transported downstream to the stock unit <NUM>. Sheets S, including the sheet S, are stacked in the stock unit <NUM>.

An ejection mechanism <NUM> has a function of transporting the sheet S having been cut into a separate shape to the stock unit <NUM>. The ejection mechanism <NUM> includes post-cutting rollers <NUM>, intermediate rollers <NUM>, first ejection rollers <NUM>, and second ejection rollers <NUM>. The intermediate rollers <NUM>, the first ejection rollers <NUM>, and the second ejection rollers <NUM> are arranged in this order from the upstream in the transport direction of the sheet S, that is, from the -x side.

Each of the post-cutting rollers <NUM>, the intermediate rollers <NUM>, the first ejection rollers <NUM>, and the second ejection rollers <NUM> are disposed as a roller pair, with the transportation path <NUM> traversing between the two rollers of each pair.

The post-cutting rollers <NUM> are disposed as a pair of rollers between the first cutter <NUM> and the second cutter <NUM>, with the transportation path <NUM> traversing through a z-directional gap between the two rollers of the pair. The post-cutting rollers <NUM> contribute to transportation within a segment from the cutting of the continuous sheet S0 by the first cutter <NUM> till handover to the intermediate rollers <NUM>. With the sheet S nipped between the post-cutting rollers <NUM>, each of the post-cutting rollers <NUM> rotates in a direction indicated by an arrow in <FIG>. By this rotation, it is possible to transport the sheet S after the cutting process in the +x direction.

One of the pair of post-cutting rollers <NUM> is a master roller that is driven by the operation of a motor that is not illustrated, and the other is a slave roller. As illustrated in <FIG>, the motor-driven one of the pair of post-cutting rollers <NUM> is electrically coupled to the control unit <NUM>. Its operation is controlled by the control unit <NUM>.

The intermediate rollers <NUM> are disposed as a pair of rollers downstream of the second cutter <NUM>, that is, on the +x side with respect to the second cutter <NUM>, with the transportation path <NUM> traversing through a z-directional gap between the two rollers of the pair. The intermediate rollers <NUM> contribute to, especially, transportation of the sheet S after cutting off waste edges. With the sheet S nipped between the intermediate rollers <NUM>, each of the intermediate rollers <NUM> rotates in a direction indicated by an arrow in <FIG>. By this rotation, it is possible to transport, in the +x direction, the sheet S after cutting off waste edges.

One of the pair of intermediate rollers <NUM> is a master roller that is driven by the operation of a motor that is not illustrated, and the other is a slave roller. As illustrated in <FIG>, the motor-driven one of the pair of intermediate rollers <NUM> is electrically coupled to the control unit <NUM>. Its operation is controlled by the control unit <NUM>.

The first ejection rollers <NUM> are disposed as a pair of rollers downstream of the intermediate rollers <NUM>, that is, on the +x side with respect to the intermediate rollers <NUM>, with the transportation path <NUM> traversing through a z-directional gap between the two rollers of the pair. The first ejection rollers <NUM> contribute to, especially, transportation of the sheet S toward the stock unit <NUM>. With the sheet S nipped between the first ejection rollers <NUM>, each of the first ejection rollers <NUM> rotates in a direction indicated by an arrow in <FIG>. By this rotation, it is possible to transport the sheet S in the +x direction.

One of the pair of first ejection rollers <NUM> is a master roller that is driven by the operation of a motor that is not illustrated, and the other is a slave roller. As illustrated in <FIG>, the motor-driven one of the pair of first ejection rollers <NUM> is electrically coupled to the control unit <NUM>. Its operation is controlled by the control unit <NUM>.

The second ejection rollers <NUM> are disposed as a pair of rollers downstream of the first ejection rollers <NUM>, that is, on the +x side with respect to the first ejection rollers <NUM>, with the transportation path <NUM> traversing through a z-directional gap between the two rollers of the pair. The second ejection rollers <NUM> contribute to, especially, transportation of the sheet S to the stock unit <NUM>. With the sheet S nipped between the second ejection rollers <NUM>, each of the second ejection rollers <NUM> rotates in a direction indicated by an arrow in <FIG>. By this rotation, it is possible to transport the sheet S to the stock unit <NUM>.

One of the pair of second ejection rollers <NUM> is a master roller that is driven by the operation of a motor that is not illustrated, and the other is a slave roller. As illustrated in <FIG>, the motor-driven one of the pair of second ejection rollers <NUM> is electrically coupled to the control unit <NUM>. Its operation is controlled by the control unit <NUM>.

The rotation speed of each of the post-cutting rollers <NUM>, the intermediate rollers <NUM>, the first ejection rollers <NUM>, and the second ejection rollers <NUM> described above is adjusted into an appropriate speed by the control unit <NUM>.

The transportation unit <NUM> is provided between the heating rollers <NUM> and the separate sheet shaping unit <NUM>. The transportation unit <NUM> transports the continuous sheet S0 formed by the sheet forming unit <NUM> to the separate sheet shaping unit <NUM>. In the present embodiment, the transportation unit <NUM> is comprised of a pair of transportation rollers 251A. However, the scope of the present disclosure is not limited to this example. For example, the transportation unit <NUM> may be configured as an endless belt that performs sheet transportation by rotating.

The transportation rollers 251A constituting the pair are disposed such that the transportation path <NUM> traverses through a z-directional gap therebetween. With the sheet S nipped between the transportation rollers 251A, each of the transportation rollers 251A rotates in a direction indicated by an arrow in <FIG>. By this rotation, it is possible to transport the continuous sheet S0 to the separate sheet shaping unit <NUM>.

One of the pair of transportation rollers 251A is a master roller that is driven by the operation of a motor that is not illustrated, and the other is a slave roller. As illustrated in <FIG>, the motor-driven one of the pair of transportation rollers 251A is electrically coupled to the control unit <NUM>. Its operation is controlled by the control unit <NUM>.

The tension adjustment unit <NUM> has a function of adjusting a tension applied to the continuous sheet S0. The tension adjustment unit <NUM> is provided between the cutting-off unit <NUM> and the transportation rollers 251A above the upper surface of the sheet S that is being transported, that is, on the +z side. The tension adjustment unit <NUM> may be provided below the lower surface of the sheet S that is being transported, that is, on the -z side.

In the present embodiment, the tension adjustment unit <NUM> includes a roller 261A, a movement mechanism 262A such as a motor or a solenoid, and a tension detector 263A. The operation of the movement mechanism 262A brings the roller 261A closer to and away from the continuous sheet S0 that is moving. The tension is high in a state in which the roller <NUM> is pressed against the continuous sheet S0. The tension of the continuous sheet S0 is loosened in a state in which the roller <NUM> is retracted away from the position of being pressed against the continuous sheet S0. As illustrated in <FIG>, the movement mechanism 262A is electrically coupled to the control unit <NUM>. Its operation is controlled by the control unit <NUM>.

In the present embodiment, the tension detector 263A is a torque sensor coupled to the roller 261A. The tension detector 263A is electrically coupled to the control unit <NUM>. Information regarding a torque value detected by the tension detector 263A is transmitted to the control unit <NUM>. Based on the Information regarding the torque value, the control unit <NUM> estimates the tension.

However, the scope of the present disclosure is not limited to this configuration. For example, the tension detector 263A may be in contact with the continuous sheet S0 and measure the tension directly.

As explained above, the sheet manufacturing apparatus <NUM> includes the tension adjustment unit <NUM> configured to adjust the tension of the continuous sheet S0 between the pressing portion <NUM> and the transportation unit <NUM>. With this configuration, it is possible to reduce the occurrence of transportation abnormality such as jamming by adjusting the tension of the continuous sheet S0. Moreover, when a part of the continuous sheet S0 needs to be cut off due to the occurrence of transportation abnormality, this configuration makes it possible to cut off the part well by adjusting the tension of the continuous sheet S0.

The tension adjustment unit <NUM> lowers the tension of the continuous sheet S0 when a part of the continuous sheet S0 is to be cut off. This prevents the cutting of the continuous sheet S0 under extreme tension. Therefore, it is possible to obtain a cut end having a desired shape. Moreover, it is possible to prevent or reduce the movement of the end of the continuous sheet S0 to an unexpected position when the cutting is performed.

The tension adjustment unit <NUM> includes the roller 261A provided between the cutting-off unit <NUM> and the transportation unit <NUM> and capable of being brought closer to and away from the continuous sheet S0. This configuration makes it possible to adjust the tension of the continuous sheet S0 with further enhanced adjustment performance.

The cutting-off unit <NUM> is provided between the pressing rollers <NUM> and the transportation unit <NUM>. The cutting-off unit <NUM> has a function of, when transportation abnormality has occurred on the continuous sheet S0 that is being transported, cutting off a part of the continuous sheet S0 where the transportation abnormality has occurred from the continuous sheet S0.

The cutting-off unit <NUM> includes a pair of rollers <NUM> and cutting blades <NUM>. These rollers <NUM> constituting the pair are provided at a distance from each other in the thickness direction of the continuous sheet S0 that is being transported, namely, in the z-axis direction. The cutting blade <NUM> protrudes from the circumferential surface of each of the pair of rollers <NUM>. The cutting blade <NUM> is provided in such a way as to extend in the shaft direction of each of the pair of rollers <NUM>.

Each roller <NUM> rotates in a direction indicated by an arrow in <FIG>. During the rotation, the cutting blades <NUM> come into contact with each other. Due to this blade contact, the continuous sheet S0 passing therebetween is cut. As illustrated in <FIG>, the cutting-off unit <NUM> is electrically coupled to the control unit <NUM>. Its operation is controlled by the control unit <NUM>. That is, a non-illustrated motor coupled to each roller <NUM> is electrically coupled to the control unit <NUM>. Its operation is controlled by the control unit <NUM>.

The configuration of the cutting-off unit <NUM> is not limited to the above example. For example, the cutting-off unit <NUM> may be configured to cut off the part while moving in a direction intersecting with the transportation direction of the continuous sheet S0. The cutting-off unit <NUM> may be configured to cut off the part while moving in the z-axis direction. The cutting-off unit <NUM> may be configured to cut off the part by emitting an energy beam such as a laser beam.

The abnormality detection unit <NUM> has a function of detecting the occurrence of transportation abnormality on the continuous sheet S0 that is being transported. The abnormality detection unit <NUM> is provided between the tension adjustment unit <NUM> and the transportation unit <NUM>. In the present embodiment, the abnormality detection unit <NUM> is an optical sensor. The abnormality detection unit <NUM> is provided at a position that is not on the transportation path <NUM> of the continuous sheet S0. In the illustrated configuration, the abnormality detection unit <NUM> is provided on the +z side with respect to the transportation path <NUM>. Therefore, when the continuous sheet S0 goes off the transportation path <NUM>, the abnormality detection unit <NUM> is able to detect it. The abnormality detection unit <NUM> is electrically coupled to the control unit <NUM>. Information detected by the abnormality detection unit <NUM>, that is, information on the occurrence of transportation abnormality, is transmitted to the control unit <NUM>. The term "transportation abnormality" means a status that the continuous sheet S0 goes off the supposed course of the transportation path <NUM>. Specifically, the term "transportation abnormality" means jamming, distortion, tearing, and the like.

As described above, the sheet manufacturing apparatus <NUM> includes the abnormality detection unit <NUM> that is an example of a detection unit that detects the transportation abnormality of the continuous sheet S0. With this configuration, it is possible to detect the occurrence of transportation abnormality on the continuous sheet S0. The abnormality detection unit <NUM> may be omitted, and an operator may find transportation abnormality by a visual check. In this case, upon finding the transportation abnormality, the operator activates the cutting-off unit <NUM>.

As illustrated in <FIG>, the control unit <NUM> includes a CPU (Central Processing Unit) <NUM> and a storage unit <NUM>. The CPU <NUM> is able to, for example, perform various kinds of determination and give various kinds of instructions.

Various programs such as, for example, a program for manufacturing sheets S are stored in the storage unit <NUM>.

The control unit <NUM> may be built in the sheet manufacturing apparatus <NUM>, or may be provided in an external device such as an external computer. The external device may, for example, communicate with the sheet manufacturing apparatus <NUM> via a cable or the like or wirelessly. The external device may be connected to the sheet manufacturing apparatus <NUM> via a network such as, for example, the Internet.

The CPU <NUM> and the storage unit <NUM> may be, for example, integrated into a single unitized component. The CPU <NUM> may be built in the sheet manufacturing apparatus <NUM>, and the storage unit <NUM> may be provided in an external device such as an external computer. The storage unit <NUM> may be built in the sheet manufacturing apparatus <NUM>, and the CPU <NUM> may be provided in an external device such as an external computer.

In the sheet manufacturing apparatus <NUM> described above, when transportation abnormality occurs as illustrated in <FIG>, the abnormality detection unit <NUM> detects it. Then, as illustrated in <FIG>, the transportation of the continuous sheet S0 is stopped, and the tension adjustment unit <NUM> loosens the tension of the continuous sheet S0 into a tension value that is suitable for cutting off the part. Next, as illustrated in <FIG>, the rollers <NUM> of the cutting-off unit <NUM> are rotated so as to cut the continuous sheet S0 by the cutting blades <NUM>. Finally, as illustrated in <FIG>, the part X cut off from the continuous sheet S0 is removed.

With this configuration, it is possible to cut off the part X where the transportation abnormality has occurred from the continuous sheet S0, and to remove the part X. In particular, the continuous sheet S0 has a continuous sheet form that is relatively long. In related art, if transportation abnormality occurs on such a long continuous sheet, the apparatus is temporarily stopped, and the location of the abnormality is identified. Then, in related art, after the identifying of the location of the abnormality, an operator cuts off the part where the abnormality has occurred, and removes the part cut off. In the present disclosure, the cutting-off unit <NUM> cuts off a part of the continuous sheet S0, including the part X where the transportation abnormality has occurred, specifically, cuts off the part from the position of cutting by the cutting-off unit <NUM> to the position of cutting by the first cutter <NUM>. Therefore, it is possible to troubleshoot and clear the transportation abnormality just by removing the part cut off, which is easy.

The scope of the present disclosure is not limited to the above configuration, in which the operation of the cutting-off unit <NUM> is controlled by the control unit <NUM>. For example, the operator may operate the cutting-off unit <NUM> manually.

As described above, the sheet manufacturing apparatus <NUM> includes: the pressing portion <NUM> that includes the pressing roller <NUM> that presses the second web M8, which is a material containing fibers and the binder P1, the binder P1 having a function of bonding the fibers together, to form the material into a shape of the continuous sheet S0; the separate sheet shaping unit <NUM> that cuts the continuous sheet S0 into a shape of the sheet S, which is an example of a separate sheet; the transportation unit <NUM> provided between the pressing roller <NUM> and the separate sheet shaping unit <NUM> and configured to transport the continuous sheet S0 formed by the pressing portion <NUM> to the separate sheet shaping unit <NUM>; and the cutting-off unit <NUM> provided between the pressing roller <NUM> and the transportation unit <NUM>, wherein, when transportation abnormality occurs on the continuous sheet S0 that is being transported, the cutting-off unit <NUM> cuts off, from the continuous sheet S0, a part X of the continuous sheet S0 where the transportation abnormality occurs. With this configuration, when transportation abnormality occurs, it is possible to cut off the part, of the continuous sheet S0, from the position of cutting by the cutting-off unit <NUM> to the position of cutting by the separate sheet shaping unit <NUM>. Therefore, it is possible to troubleshoot and clear the transportation abnormality just by removing the part cut off, which is easy.

It is especially difficult to troubleshoot and clear the transportation abnormality by using related art if the transportation unit <NUM> includes the pair of transportation rollers 251A and, in addition, if the transportation abnormality is jamming that occurs on the pair of transportation rollers 251A. Therefore, the advantageous effect of the present disclosure is more conspicuous in this case.

The cutting-off unit <NUM> cuts off a part, of the continuous sheet S0, located downstream of the pressing roller <NUM> and upstream of the part X where the transportation abnormality occurs, in a direction intersecting with a transportation direction of the continuous sheet S0. Therefore, the sheet cut off includes the part X. This makes it possible to remove the part X where the transportation abnormality occurs, with enhanced removal reliability.

The cutting-off unit <NUM> has the cutting blade <NUM> extending in a direction intersecting with the transportation direction of the continuous sheet S0. This makes it possible to cut the continuous sheet S0 in the width direction easily and thus makes it possible to cut off the part speedily.

Next, with reference to the flowchart of <FIG>, the control operation performed by the control unit <NUM> will now be explained.

First, in a step S101, manufacturing of sheets is started. That is, each component of the sheet manufacturing apparatus <NUM> is activated so as to start the manufacturing of sheets S.

Next, in a step S102, it is determined whether transportation abnormality is detected or not. The determination in this step is made based on the result of detection by the abnormality detection unit <NUM>.

If it is determined in the step S102 that transportation abnormality has occurred, transportation is stopped in a step S103. That is, the operation of relevant components of the sheet manufacturing apparatus <NUM>, in particular, the operation of the transportation unit <NUM>, is stopped. When the transportation is stopped, preferably, a non-illustrated notification unit may output a notification to the effect that the transportation abnormality has occurred. If it is determined in the step S102 that no transportation abnormality has occurred, the process proceeds to a step S108.

Next, in a step S104, the tension of the continuous sheet S0 is adjusted. For example, as illustrated in <FIG>, this step is executed by bringing the roller 261A of the tension adjustment unit <NUM> away from the continuous sheet S0.

Next, in a step S105, the cutting-off unit <NUM> is activated so as to cut off, from the continuous sheet S0, the part X of the continuous sheet S0 where the transportation abnormality has occurred. Then, the operator removes the sheet including the cut-off part X.

Next, in a step S106, it is determined whether an instruction for restarting sheet manufacturing is given or not. The determination in this step is made based on, for example, whether a non-illustrated restart button is pressed by the operator or not. If it is determined in the step S106 that an instruction for restarting sheet manufacturing is given, sheet manufacturing is restarted in a step S107. If it is determined in the step S106 that no instruction for restarting sheet manufacturing is given, the process waits until there is an input of a restart instruction.

Next, in a step S108, it is determined whether sheet manufacturing has finished or not. The determination in this step is made based on, for example, whether the number of sheets S that have been manufactured has reached a predetermined number of sheets or not. If it is determined in the step S108 that sheet manufacturing has finished, the running of the program is ended. If it is determined in the step S108 that sheet manufacturing has not finished yet, the process returns to the step S102, and the step S102 and the subsequent steps are executed in sequence.

As described above, the sheet manufacturing apparatus <NUM> includes the control unit <NUM> that controls the operation of the cutting-off unit <NUM> based on the result of detection by the abnormality detection unit <NUM>, which is an example of a detection unit. With this configuration, when transportation abnormality occurs, it is possible to cut off the part, of the continuous sheet S0, from the position of cutting by the cutting-off unit <NUM> to the position of cutting by the separate sheet shaping unit <NUM>. Therefore, it is possible to remove the part X where the transportation abnormality has occurred just by removing this part, which is easy.

Claim 1:
A sheet manufacturing apparatus <NUM>, comprising:
a pressing unit (<NUM>) that includes a pressing roller (<NUM>) that presses a material (M8) containing fibers (M6) and a binder (P1), the binder (P1) having a function of bonding the fibers (M6) together, to form the material (M8) into a shape of a continuous sheet (SO);
a separate sheet shaping unit (<NUM>) that cuts the continuous sheet (SO) into a shape of a separate sheet (S);
a transportation unit (<NUM>) provided between the pressing roller (<NUM>) and the separate sheet shaping unit (<NUM>) and configured to transport the continuous sheet (SO) formed by the pressing unit (<NUM>) to the separate sheet shaping unit (<NUM>); characterised by
a cutting-off unit (<NUM>) provided between the pressing roller (<NUM>) and the transportation unit (<NUM>), configured S0 that, when transportation abnormality occurs on the continuous sheet (SO) that is being transported, the cutting-off unit (<NUM>) cuts off, from the continuous sheet (SO), a part of the continuous sheet where the transportation abnormality occurs.