Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B31—MAKING ARTICLES OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER; WORKING PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B—MAKING CONTAINERS OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B50/00—Making rigid or semi-rigid containers, e.g. boxes or cartons
  • B31B50/02—Feeding or positioning sheets, blanks or webs
  • B31B50/04—Feeding sheets or blanks
  • B31B50/042—Feeding sheets or blanks using rolls, belts or chains
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B31—MAKING ARTICLES OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER; WORKING PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B—MAKING CONTAINERS OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B50/00—Making rigid or semi-rigid containers, e.g. boxes or cartons
  • B31B50/02—Feeding or positioning sheets, blanks or webs
  • B31B50/04—Feeding sheets or blanks
  • B31B50/044—Feeding sheets or blanks involving aligning
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B31—MAKING ARTICLES OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER; WORKING PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B—MAKING CONTAINERS OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B50/00—Making rigid or semi-rigid containers, e.g. boxes or cartons
  • B31B50/74—Auxiliary operations
  • B31B50/741—Moistening; Drying; Cooling; Heating; Sterilizing
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B31—MAKING ARTICLES OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER; WORKING PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B—MAKING CONTAINERS OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B50/00—Making rigid or semi-rigid containers, e.g. boxes or cartons
  • B31B50/74—Auxiliary operations
  • B31B50/742—Coating; Impregnating; Waterproofing; Decoating
  • B31B50/743—Coating or impregnating edges or corners
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B31—MAKING ARTICLES OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER; WORKING PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B—MAKING CONTAINERS OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B50/00—Making rigid or semi-rigid containers, e.g. boxes or cartons
  • B31B50/74—Auxiliary operations
  • B31B50/742—Coating; Impregnating; Waterproofing; Decoating
  • B31B50/747—Coating or impregnating blanks or webs
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B31—MAKING ARTICLES OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER; WORKING PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B—MAKING CONTAINERS OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B50/00—Making rigid or semi-rigid containers, e.g. boxes or cartons
  • B31B50/74—Auxiliary operations
  • B31B50/81—Forming or attaching accessories, e.g. opening devices, closures or tear strings
  • B31B50/812—Applying tabs, patches, strips or strings on blanks or webs
  • B31B50/8125—Applying strips or strings, e.g. tear strips or strings
  • B31B50/8126—Applying strips or strings, e.g. tear strips or strings parallel to the direction of movement of the webs or the blanks
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B31—MAKING ARTICLES OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER; WORKING PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B—MAKING CONTAINERS OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B50/00—Making rigid or semi-rigid containers, e.g. boxes or cartons
  • B31B50/74—Auxiliary operations
  • B31B50/81—Forming or attaching accessories, e.g. opening devices, closures or tear strings
  • B31B50/812—Applying tabs, patches, strips or strings on blanks or webs
  • B31B50/8125—Applying strips or strings, e.g. tear strips or strings
  • B31B50/8129—Applying strips or strings, e.g. tear strips or strings the webs or blanks moving during application of the strips or strings
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B31—MAKING ARTICLES OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER; WORKING PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31F—MECHANICAL WORKING OR DEFORMATION OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31F5/00—Attaching together sheets, strips or webs; Reinforcing edges
  • B31F5/06—Attaching together sheets, strips or webs; Reinforcing edges by adhesive tape
  • B31F5/08—Attaching together sheets, strips or webs; Reinforcing edges by adhesive tape for reinforcing edges ; Applying a strip or tape to an edge, e.g. for decorating, for protecting
  • B31F5/085—Attaching together sheets, strips or webs; Reinforcing edges by adhesive tape for reinforcing edges ; Applying a strip or tape to an edge, e.g. for decorating, for protecting combined with folding the strip around the edge, or applying an already folded strip on
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
  • B65H37/00—Article or web delivery apparatus incorporating devices for performing specified auxiliary operations
  • B65H37/04—Article or web delivery apparatus incorporating devices for performing specified auxiliary operations for securing together articles or webs, e.g. by adhesive, stitching or stapling
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B31—MAKING ARTICLES OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER; WORKING PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B—MAKING CONTAINERS OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B2105/00—Rigid or semi-rigid containers made by assembling separate sheets, blanks or webs
  • B31B2105/002—Making boxes characterised by the shape of the blanks from which they are formed
  • B31B2105/0022—Making boxes from tubular webs or blanks, e.g. with separate bottoms, including tube or bottom forming operations
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B31—MAKING ARTICLES OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER; WORKING PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B—MAKING CONTAINERS OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B2110/00—Shape of rigid or semi-rigid containers
  • B31B2110/10—Shape of rigid or semi-rigid containers having a cross section of varying size or shape, e.g. conical or pyramidal
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B31—MAKING ARTICLES OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER; WORKING PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B—MAKING CONTAINERS OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B2110/00—Shape of rigid or semi-rigid containers
  • B31B2110/20—Shape of rigid or semi-rigid containers having a curved cross section, e.g. circular

Definitions

• the present invention relates to a technique for waterproofing end faces of blanks used to form paper containers such as paper cups, and more particularly to an end face tape application apparatus and an end face tape application method for covering end faces of blanks with tapes.
• Laminated paper is conventionally used for paper containers such as paper cups because unprocessed raw paper has poor water resistance and poor gas barrier properties.
• the raw paper (paper base) is coated with resin as a waterproof layer on the surface that forms the inside of the container.
• An inverted truncated cone paper cup body is formed by rolling a blank that has been cut into a fan shape. Lateral ends thereof are then placed on top of each other, with one of the lateral ends (bonding end) being the inside and the other of the lateral ends being the outside, and bonded together in a liquid-tight manner. It is known to perform edge treatment on the end face of the one lateral end of the blank that is to be the inside so as to prevent exposure of the raw paper in the end face and to ensure water resistance.
• An example of edge treatment include a skive and hem process (e.g., see Patent Literature 1) in which the outside of a lateral end portion of the blank is cut to about half thickness and the remaining portion of about half thickness is folded back onto the outside and tightly bonded to the portion subjected to the cutting; and another example is a coating process in which a blank is heat sealed with a film of the same length as the blank and in which the blank is inserted into a small clearance between cut pieces of the film held by suction on upper and lower sealing bars; and yet another example is a coating process in which a resin film laminated on the surface of the raw paper as a waterproof barrier is cut, with an overhang thereof protruding from the lateral edge of the raw paper and folded back, and bonded to the back side (e.g., see Patent Literature 2 and 3).
• a skive and hem process e.g., see Patent Literature 1
• a coating process in which a blank is heat sealed with a film of the same length as the blank and in which
• the skive and hem process may involve generation of paper powder, glue contamination, and other sanitary issues.
• the problems with the coating process in which the blank, which is interposed, is heat sealed with a film held by suction on upper and lower sealing bars are that films of different widths are required according to the sizes of the blanks to be processed, and that the system is complex and cannot operate at high speed.
• the resin film laminated on the raw paper is folded back, the resin film has to be cut to a larger size than the raw paper. This additional cutting process reduces productivity.
• dedicated process steps and blanks are required, which compromises versatility.
• One example is a process in which a separately prepared piece of waterproof tape is applied to the front and back of the lateral end of the blank to cover the end face (e.g., see Patent Literature 4 to 6).
• the present invention solves the problems described above, an object thereof being to provide a simply structured end face tape application apparatus and an end face tape application method that can suppress the generation of tape application failures such as creasing and peeling even under high-speed processing on blank end faces, and can implement automatic folding of the tape onto the back side of the blank as the blank is conveyed.
• the end face tape application apparatus and end face tape application method according to the present invention enable end face processing by tape application in a short time and with a high yield, thereby improving production efficiency.
• the end face tape application apparatus is an apparatus for covering an end face of a bonding end of a blank by applying a strip of tape to the bonding end of the blank.
• the apparatus includes: a conveyance system configured to convey the blank along a conveying path; and a blank-heating system, a tape application system, a tape-folding system, and a heat-bonding system arranged along the conveying path from an upstream side.
• the blank-heating system is configured to heat the bonding end of the blank.
• the tape-folding system is configured to fold back an overhanging portion of the tape applied to the blank along the bonding edge of the blank.
• the heat-bonding system is configured to apply a folded portion of the tape to a bonding end area on another side of the blank.
• the tape application system preferably reels out the tape synchronously with a speed at which the conveyance system conveys the blank.
• the tape-folding system includes a passage with one side open for allowing the bonding end of the blank to pass through while the blank is conveyed.
• the passage may include a folding wall, whose angle relative to a blank plane reduces continuously, as the blank advances in the blank-conveying direction.
• the tape-folding system is preferably configured to fold back the tape such that a gap is formed between the end face of the bonding end of the blank and the tape.
• the end face tape application apparatus may further include a tape-tacking system arranged between the tape application system and the tape-folding system, the tape-tacking system being configured to heat bond the tape at least to a portion on an upstream side in the blank-conveying direction of the bonding end area on one side of the blank.
• the heat-bonding system may include: a first heat-bonding unit configured to heat bond a folded portion of the tape to a portion of a bonding end area on another side of the blank; and a second heat-bonding unit configured to heat bond an entire surface of the tape that has been partially tacked by the first heat-bonding unit.
• the first heat-bonding unit may include a tape-correcting guide configured to maintain the tape that has been folded back by the tape-folding system in a folded state in which the tape is forcibly brought into close proximity to the other side of the blank.
• An end face tape application method is a method for covering an end face of a bonding end of a blank by applying a strip of tape to the bonding end of the blank, the method including:
• the blank-heating system heats the bonding end of the blank in advance, and the tape application system applies the tape to one side of the blank, with an overhang thereof protruding from the bonding edge.
• the tape-folding system folds back the overhanging portion of the tape, and the heat-bonding system applies the folded portion of the tape to the blank.
• the tape is applied to both the front and the back of the bonding end of the blank, essentially covering the end face to prevent the exposure of raw paper and to provide the desired water resistance.
• the apparatus and method enable high-speed, continuous and automatic processing of blank end faces with a simple structure and high precision, minimizing tape application failures such as creasing and peeling.
• the tape is folded back onto the back side of the blank as the blank is conveyed, allowing the end face to be taped in a short time and with a high yield, thereby improving production efficiency.
• the tape is cut to a length that matches the bonding end of the blank in the tape application system, meaning that the tape can be fed in the length that matches the blank even when the blank specifications are changed. This obviates the need to change the width of the tape according to a change in blank specifications, providing greater versatility.
• the tape application system is configured to reel out the tape synchronously with a speed at which the blank is conveyed.
• the tape is fed synchronously while the preheated blank is conveyed.
• the blank and the tape, moving at the equivalent speed, are brought into contact so that the tape T is applied to the blank B. In this way, the tape can be applied precisely and without creases, even at high speeds.
• the tape-folding system includes a passage that has a folding wall, whose angle relative to a blank plane reduces continuously, as the blank advances in the blank-conveying direction, and that is open on one side.
• the tape that was applied to the bonding end area on one side of the blank is folded back nearly 180° onto the other side of the blank by simply passing the blank through the passage as it is conveyed. In this way, the tape can be reliably folded back with a simple structure, and applied to the bonding end area on the other side of the blank with high precision, so that production efficiency is further improved.
• the tape-folding system is configured to fold back the tape such that a gap is formed between the end face of the bonding end of the blank and the tape.
• the gap formed between the end face of the blank and the tape tolerates variations in the end face position of the blank or the tape-folding precision.
• the redundant portion of the tape forming the gap is melted during heat sealing in a subsequent process of forming the blank into a final product, providing the resin material for filling up an inevitable gap formed between blanks.
• the end face tape application apparatus further includes a tape-tacking system configured to heat bond the tape at least to a portion on an upstream side in the blank-conveying direction of the bonding end area on one side of the blank. This ensures that at least the leading end in the blank-conveying direction of the tape fed for the blank can be tacked to one side of the blank. This reliably prevents the tape from creasing or shifting when it is folded back in the tape-folding system, and enables the tape to be applied to the blank end face with greater precision.
• the heat-bonding system includes a first heat-bonding unit configured to heat bond a portion of the tape to a bonding end area on the other side of the blank, and a second heat-bonding unit configured to heat bond an entire surface of the tape.
• the tape is reliably tacked to the other side of the blank in the first heat-bonding unit before entire heat bonding is implemented thereon in the second heat-bonding unit. This reliably prevents the tape from creasing or shifting when it is entirely heat bonded, and enables the tape to be applied to the blank end face with greater precision.
• the first heat-bonding unit includes a tape-correcting guide.
• the tape-correcting guide reliably maintains the tape in its folded state as the tape is heat bonded to the bonding end area on the other side of the blank. This reliably tacks the tape precisely to the desired position and enables the tape to be applied to the blank end face with greater precision.
• the tape may rebound back to its original shape or to an intermediate state where it is bent at an angle after exiting the tape-folding system.
• the end face tape application apparatus is an apparatus for continuous and automated end face processing in which an end face of a blank that is the material for paper containers such as paper cups is covered with a strip or piece of tape.
• the purpose of this end face processing is to provide the container with high water resistance by preventing exposure of the raw paper in the end face at the bonding end of the blank that will be positioned inside the container, thereby preventing liquid from seeping through the end face of the blank.
• a blank B which is to be processed by the end face tape application apparatus of the present invention, is used to form the body of a paper cup, for example, and has a fan shape in plan view as shown in Fig. 1A .
• a fan shape is defined as a shape cut from a circular ring by two straight lines extending radially from the center (where a folding fan has its pivot pin) and at acute angles to each other.
• a piece of tape T is applied to a lateral end (bonding end) that corresponds to one of the straight lines.
• the blank B can be obtained by die cutting laminated paper 1 into a predetermined shape.
• the die-cutting process is not limited to a specific method. For example, any of a number of known die-cutting machines may be used to cut the paper.
• the laminated paper 1 has resin layers 3, 3 as a waterproof barrier formed on both surfaces of raw paper 2, which is the main material, as shown in Fig. 1B . From the viewpoint of providing water resistance to the final paper container produced from the blank B, the resin layer 3 may be formed at least on the surface that will be the inside of the container.
• the laminated paper 1 may have a laminated structure with three or more layers.
• the resin layers 3 may be made of different resin materials.
• the laminated paper may further include a metal deposition layer as a barrier layer, a print layer, an adhesive layer, and so on.
• the blank B (laminated paper 1) has a thickness of 150 to 450 ⁇ m, for example.
• the resin layer 3 may have a thickness with which it can exhibit heat-sealing properties when the blank B is heat bonded together to form the paper container, which is, for example, in the range of 10 to 80 ⁇ m. An appropriate thickness may be set according to the location of the heat-bonded area.
• raw paper 2 Various types of known raw paper materials can be used as the raw paper 2 according to the shape or preferred strength of the paper container.
• any materials having both water resistance and heat-sealing properties may be used preferably, including but not limited to: polyolefin resins such as polyethylene and polypropylene, polyvinyl alcohol resins, acrylic acid resins, methacrylic acid resins, vinyl chloride resins, polyvinylidene chloride resins, vinyl acetate resins, polyurethane resins, polyester resins such as polyethylene terephthalate, polyamide resins such as nylon 6 and nylon 6,6, polystyrene resins, phenol resins, and mixtures of these resins. Of these, polyethylene resins are more preferable in terms of water resistance, heat-sealing properties, and the glass transition point.
• the tape T to be applied to the lateral end of the blank B is made of a film with a resin surface layer that is thermally bondable to the blank B.
• the tape may have either a single-layer structure or a multi-layer structure.
• the tape T should preferably have a thickness of 50 to 100 ⁇ m, for example, for reasons of foldability and durability.
• the tape T may have a layer structure composed of, for example, a 20 ⁇ m thick polyethylene resin layer, a 12 ⁇ m thick polyethylene terephthalate resin layer, and a 20 ⁇ m thick polyethylene resin layer.
• the tape T is supplied in the form of a long, narrow, uncut roll of tape to a tape application system 120 that will be described later in more detail.
• the tape T has a width of 5 to 20 mm, for example, preferably around 10 mm. Too large a tape T width will inevitably increase the size of the tape-folding system. If the tape T width is too small, it may be difficult to reliably heat bond the tape T to both the front and the back of the lateral end of the blank B.
• the end face tape application apparatus 100 performs end face processing in which a strip of tape T is applied to a lateral end (bonding end) of the blank B to cover the end face E of the lateral end.
• the apparatus includes: a conveyance system 101 configured to convey the blanks B along a conveying path; a blank-heating system 110 configured to perform a blank-heating process of heating a lateral end of the blank B; a tape application system 120 configured to perform a tape application process of applying one half T1 of the tape T that is approximately one half in width of an already cut tape T (hereinafter, "left half") to a bonding end area A1 at the lateral end of the blank B on a front side (one side) thereof; a tape-tacking system 130 configured to perform a tape-tacking process of heat bonding the tape T to a portion on an upstream side in the blank-conveying direction of the bonding end area A1; a tape-folding system
• blank-heating system 110, tape application system 120, tape-tacking system 130, tape-folding system 140, first heat-bonding unit 150, and second heat-bonding unit 160 are arranged sequentially from an upstream side of a straight conveying path, so that each step of the end face tape application method is carried out at respective points as the blanks B are transported.
• the blank-heating system 110, the tape application system 120, tape-tacking system 130, tape-folding system 140, first heat-bonding unit 150, and second heat-bonding unit 160 are controlled to operate in coordination with each other during the intermittent transport by the conveyance system 101.
• the end face tape application apparatus 100 can continuously perform the process of covering the end face E of the lateral end of the blank B with the tape T.
• the end face tape application apparatus 100 processes blanks B at a speed of 120 to 180 units/min, preferably at 150 units/min or more, for example.
• the conveyance system 101 is designed for continuous intermittent transport of blanks B in one direction. More specifically, the system transports blanks B along a straight line such that the longitudinal direction of the end face E of the lateral end of the blank B to be processed (the direction in which the lateral edge F extends) coincides with the conveying direction.
• the conveyance system 101 has a conveyor lane 102.
• the blank B is transported with its central portion being supported so that the lateral end of the blank B to be processed is in the air (see Fig. 3B ), i.e., with a portion of the blank B about 35 to 50 mm from the end face E overhanging outwardly from the conveyor lane 102.
• the conveyance system 101 of the end face tape application apparatus 100 employs a belt conveyor with vacuum function.
• the conveyance method is not limited to a specific system and can employ various known configurations as long as it provides the intermittent conveyance required in the present invention. For example, a conveyance method that uses grippers can be adopted.
• the blank-heating system 110 heats the front and the back of the lateral end of the blank B, to raise the temperature of the entire blank B as well as to melt the resin layers 3 on the front and back of the lateral end of the blank B.
• the blank-heating system 110 is configured with a heating unit 111 that heats the front side of the lateral end of the blank B and a heating unit 116 that heats the back side of the lateral end of the blank B, provided on the conveying path where the lateral end of the blank B passes. Heating both the front and the back of the lateral end of the blank B at the same time provides sufficient calories to the lateral end of the blank B even when the end face processing is performed on the blank B at high speed, thereby reliably raising the temperature of the blank B. This enables reliable application of the tape T to the blank B in the subsequent tape application system 120.
• These heating units 111, 116 are positioned on the conveying path where the lateral end of the blank B passes such as not to contact the blank B. Therefore, the heating process can be performed only by transporting the blank B in the conveying direction and pausing it at a predetermined position.
• the heating units 111, 116 are hot air heaters that blow out hot air from hot air outlets 112, 117 positioned at 3 to 8 mm (5 mm in this embodiment) from the front and the back of the lateral end of the blank B.
• the hot air outlets 112, 117 in this embodiment are a series of multiple fine apertures aligned approximately along the length of the lateral end of the blank B. As long as the lateral end of the blank B can be heated, the hot air outlets can have any design.
• the lateral end of the blank B may be heated to a predetermined temperature in the region including the bonding end areas A1, A2 on the front and the back where the tape T is applied.
• the blank-heating system 110 heats a 10 mm area inside the lateral edge F, for example.
• the heating unit 111 opposite the front side of the blank B may for example blow out hot air of 440° C
• the heating unit 116 opposite the back side of the blank B may for example blow out hot air of 300°C.
• the heating units 111, 116 for the front and the back of the blank B may blow out hot air of the same temperature.
• the air temperature of the heating unit 111 opposite the front side of the blank B should preferably be set higher. If the temperature of the heating units 111, 116 is set too high, the moisture in the raw paper 2 of the blank B may cause bubbles to form in the resin layer 3.
• the method of heating the blank B in the blank-heating system 110 is not limited to the one that uses hot air. As long as both of the front and the back of the lateral end of the blank B can be heated to a predetermined temperature, any of various known configurations can be adopted. For example, a heating method that uses an open flame plate can be adopted.
• the tape application system 120 feeds a strip of tape T cut to a length that matches the lateral end of the blank B as shown in Fig. 4A and Fig. 4B to the application point P (see Fig. 5B and Fig. 5C ) such that the longitudinal direction of the tape T coincides with the blank-conveying direction.
• the left half T1 of the tape T is applied to the bonding end area A1 on the front side of the blank B, leaving the right half T2 of the tape T overhanging outward (rightward in Fig. 4A and Fig. 4B ) from the lateral edge F of the blank B.
• the tape T in this example is 10 mm wide, with the left half T1 and the right half T2 of the tape T being 4.7 mm and 5.3 mm wide, respectively.
• the tape application system 120 includes: a tape-conveying unit 121 configured to reel out an uncut tape T from a tape roll (not shown) under a necessary tension applied by a tensioning roller along a tape-conveying path; a tape-cutting unit 122 configured to cut the tape T widthwise or perpendicularly to the tape-conveying direction on the tape-conveying path; and an application unit 123 arranged downstream of this tape-cutting unit 122 in the tape-conveying path and configured to apply the cut tape T to the bonding end area A1 on the front side of the blank B.
• the tape-conveying unit 121 can have any configuration as long as it is capable of conveying an extremely thin tape T without meandering.
• a tape conveyor belt 125 configured to hold the tape T by suction may be used to convey the tape.
• the conveying unit may include a groove, in which the tape is set and conveyed.
• the tape conveyor belt 125 is stretched in a circular manner between a plurality of rollers, one of which is a drive roller for driving the belt in one direction (clockwise in Fig. 5B ).
• the conveying path of the tape T in the tape-conveying unit 121 includes a section where the tape T is conveyed vertically downward.
• the tape-conveying unit 121 reels out the tape T synchronously with the speed at which the conveyance system 101 transports the blank B to the application point P. Namely, the tape T and the blank B are transported at the same speed, and conveyed at the same rate at the application point P in the application unit 123, so that creasing or shifting of the tape T is unlikely to occur during the application.
• the tape-cutting unit 122 should preferably be arranged to cut the tape T in the section of the conveying path in the tape-conveying unit 121 where the tape T is fed vertically downward.
• the tape T in the vertical orientation is subjected to a longitudinal (vertically downward) tension due to the own weight thereof so that the tape T is more rigid and travels more stably, which allows the tape T to be cut stably.
• the cut tape T is conveyed to the application unit 123 by the tape-conveying unit 121, held by suction on the tape conveyor belt 125.
• the tape width of the tape roll equals to the width of the tape T.
• the application unit 123 is configured with a drive roller 126, which also serves as the tensioning roller for the tape conveyor belt 125 in the tape-conveying unit 121, and a nip roller 127 opposite the drive roller 126 and driven to rotate synchronously therewith in the same direction at the application point.
• the tape T is conveyed in the longitudinal direction thereof prior to the tape T being cut widthwise, and the cut tapes T are also conveyed in their longitudinal direction so as to travel along the lateral edge F of the blank B.
• the conveying speed of the tape T is synchronized with the conveying speed of the blanks B, so that the blank B that has been heated by the blank-heating system 110 and the tape T are stacked and held between the drive roller 126 and the nip roller 127.
• the left half T1 of the tape T comes into contact with the bonding end area A1 on the front side of the heated blank B at the application point P. Since the resin layer 3 of the blank B in the bonding end area A1 has been melted and in a bondable state, the tape T is bonded to the area by the applied pressure.
• the drive roller 126 and the nip roller 127 are positioned relative to the thicknesses of the blank B and the tape T as follows: When the blank B and the tape T are about 0.4 mm and 0.05 mm in thickness, respectively, the drive roller 126 and the nip roller 127 are set with a clearance of about 0.45 mm therebetween.
• nip roller 127 may be positioned relative to the drive roller 126 such as to apply an appropriate nip pressure.
• the tape is applied to the blank B in a central region of the lateral end of the blank B except both upstream and downstream ends in the blank-conveying direction.
• the end regions where no tape T is bonded are about 5 mm ⁇ 1 mm in length t1, for example, in the blank-conveying direction.
• the tape T is cut by the tape-cutting unit 122 into a length h that is shorter than the length of the lateral end of the blank B (e.g., 110 mm), shorter (e.g., 100 mm) by the length of the end regions where no tape T is bonded.
• the end regions are portions that will form the curled rim or the bottom after the blank B is formed and will not be exposed inside the container.
• How much the tape T overhangs outwardly from the bonding end area A1 on the front side of the blank B depends on the width of the tape T and may be set in the range that ensures reliable application of the tape on both the front and the back of the lateral end of the blank B so that the end face E is covered.
• a preferable range is 20 to 80%, more preferably 50%, of the width of the tape T not including the end face E width.
• the method of bonding the tape T to the blank B in the application unit 123 is not limited to the one that uses two rollers to apply pressure and any of various known configurations can be adopted. For example, methods that use sealing bars (heated plates), or ultrasound, can be adopted. Depending on which method is adopted, the heat bonding may be performed while the blank B is paused, instead of during the transport of the blank B.
• the tape-tacking system 130 is arranged between the tape application system 120 and the tape-folding system 140 as shown in Fig. 6A ; it is provided for tacking the tape T to the front side of the blank B to prevent the tape T from peeling off the blank B in the tape-folding system 140 to be described later, or for greater precision in folding back the tape T.
• the left half T1 of the tape T may be heat bonded at least to a portion on the upstream side in the blank-conveying direction (leading end of the blank) of the bonding end area A1 on the front of the blank B.
• at least the leading end in the blank-conveying direction of the left half T1 of the tape T may be heat bonded to the leading end of the bonding end area A1 on the front side of the blank B.
• an area at the distal end (upper end in Fig. 7 ) of the left half T1 of the tape T, 63 mm long and spanning over the entire width (5 mm) of the left half T1 of the tape T may be heat bonded to the blank B.
• the tape T may be tacked by heat bonding the entire left half T1 of the tape T to the entire bonding end area A1.
• the tape-tacking system 130 is configured with an upper sealing bar 131 that is displaceable up and down and heats the front side of the lateral end of the blank B, and a stationary lower sealing bar 136 that heats the back side of the lateral end of the blank B, both provided on the conveying path where the lateral end of the blank B passes.
• the upper sealing bar 131 and the lower sealing bar 136 each have a size matching the area where the left half T1 of the tape T should be tacked (5 mm in width and 63 mm in length t2 in the blank-conveying direction), as shown in Fig. 7 .
• the blank B is paused at a predetermined position, and the upper sealing bar 131 is lowered, so that the predetermined area of the lateral end of the blank B where the tape T is to be tacked is held between the upper sealing bar 131 and the lower sealing bar 136, thus achieving the tacking.
• the space between the upper sealing bar 131 and the lower sealing bar 136 forms the conveying path for the lateral end of the blank B, allowing the blank B to pass through.
• the upper sealing bar 131 may be heated to, for example, 130°C, and the lower sealing bar 136 may be heated to, for example, 60°C. Since the tape T is tacked to the front side of the lateral end of the blank B, the upper sealing bar 131 should preferably be heated to a higher temperature. If the temperature of the lower sealing bar 136 is too high, the blank B may adhere to the lower sealing bar 136. If such adhesion of the tape T or blank B is unlikely to occur, the temperature of the upper sealing bar 131 and the lower sealing bar 136 may be set higher.
• the upper sealing bar 131 and the lower sealing bar 136 are provided with a non-stick surface coating such as a fluorine resin coating on the surface that makes contact with the blank B or tape T to prevent the resin layer in the blank B or tape T from adhering to the sealing bars 131, 136.
• a non-stick surface coating such as a fluorine resin coating
• the method of heat bonding the tape T to the blank B in the tape-tacking system 130 is not limited to the one that uses sealing bars (heated plates). As long as the tape T can be tacked to the blank B, any of various known configurations can be adopted. For example, a heat-bonding method that uses a fixing roller, or a method that uses ultrasound, can be adopted. Depending on which method is adopted, the heat bonding may be performed while the blanks B are transported, instead of when the transportation of the blanks B is paused.
• the tape-folding system 140 includes, as shown in Fig. 8 , a passage 141 extending in the blank-conveying direction for allowing the lateral end of the blank B to pass through as the blank B is transported.
• the passage 141 is open on one side along the blank-conveying direction (viewer's side in Fig. 8 ) so that the lateral end of the blank B that is being transported can pass.
• the passage 141 includes: a ceiling 142 positioned opposite the front side (upper side in Fig. 8 ) of the plane in which the blank B being transported extends (hereinafter, "blank plane"); a folding wall 143 whose angle relative to the blank plane reduces continuously as the blank B is transported in the blank-conveying direction; and an end wall 144 that connects the ceiling 142 and the folding wall 143.
• the folding wall 143 has a different inclination depending on the position along the blank-conveying direction, or the inclination of the wall changes continuously or stepwise as the blank moves in the blank-conveying direction.
• the inner surface of the passage 141 in the tape-folding system 140 i.e., the surface that makes contact with the blank B or tape T, is provided with a non-stick surface coating such as a fluorine resin coating, to prevent adhesion to the blank B and tape T and to achieve low friction.
• a non-stick surface coating such as a fluorine resin coating
• the right half T2 of the tape T is automatically folded back onto the back side of the blank B by the interference between the tape T and both of the end wall 144 and the folding wall 143. Eventually, the tape is folded back 180° to closely face the back side of the blank B.
• Fig. 9(a) shows a cross section of the passage 141 at 2 mm from the entrance A in the blank-conveying direction. In this position, the ceiling 142 is not in the immediate proximity.
• the folding wall 143 and the end wall 144 are integrally flat, at an angle to the ceiling 142. Since the folding wall 143 and the end wall 144 are well away from the tape T, the tape T is not folded.
• Fig. 9(b) shows a cross section of the passage 141 at 10 mm from the entrance A in the blank-conveying direction.
• the ceiling 142 is spaced 1.05 mm from the blank plane, for example.
• the folding wall 143 and the end wall 144 in this position are integrally flat, with a horizontal distance of 0.68 mm from the end face E of the blank B and at an inclination angle of 114° relative to the blank plane.
• the tape T is folded at an angle by the end wall 144 and the folding wall 143.
• Fig. 9(c) shows a cross section of the passage 141 at 20 mm from the entrance A in the blank-conveying direction.
• the ceiling 142 is in the immediate proximity of the blank plane (with distance d1 being 0.05 mm).
• the folding wall 143 and the end wall 144 in this position are integrally flat, with a horizontal distance of 0.2 mm from the end face E of the blank B and at an inclination angle of 104° relative to the blank plane.
• the tape T is folded further by the end wall 144 and the folding wall 143.
• Fig. 9(d) shows a cross section of the passage 141 at 30 mm from the entrance A in the blank-conveying direction.
• the ceiling 142 is in the same position as in Fig. 9(c) .
• the folding wall 143 and the end wall 144 in this position are integrally flat, with a horizontal distance d2 of 0.2 mm from the end face E of the blank B and at an inclination angle of 90° relative to the blank plane.
• the tape T is folded further by the end wall 144 and the folding wall 143.
• Fig. 9(e) shows a cross section of the passage 141 at 40 mm from the entrance A in the blank-conveying direction.
• the ceiling 142 is in the same position as in Fig. 9(c) .
• the end wall 144 in this position is at a horizontal distance of 0.2 mm from the end face E of the blank B and at an inclination angle of 90° relative to the blank plane.
• the end wall 144 has a vertical length (in the up and down direction in Fig. 9 ) of 0.6 mm.
• the folding wall 143 is continuous with the end wall 144 and angled at 68° to the blank plane.
• the tape T is folded by the end wall 144, and folded again at an angle by the folding wall 143.
• Fig. 9(f) shows a cross section of the passage 141 at 50 mm from the entrance A in the blank-conveying direction.
• the ceiling 142 is in the same position as in Fig. 9(c) .
• the end wall 144 is in the same position as in Fig. 9(e) .
• the folding wall 143 is continuous with the end wall 144 and angled at 37° to the blank plane. The tape T is folded further by the folding wall 143.
• Fig. 9(g) shows a cross section of the passage 141 at 60 mm from the entrance A in the blank-conveying direction.
• the ceiling 142 is in the same position as in Fig. 9(c) .
• the end wall 144 is in the same position as in Fig. 9(e) .
• the folding wall 143 is continuous with the end wall 144 and angled at 9.5° to the blank plane. The tape T is folded further by the folding wall 143.
• Fig. 9(h) shows a cross section of the passage 141 at 68 mm from the entrance A in the blank-conveying direction.
• the ceiling 142 is in the same position as in Fig. 9(c) .
• the end wall 144 is in the same position as in Fig. 9(e) .
• the folding wall 143 is continuous with the end wall 144 and angled at 0° to the blank plane.
• the tape T is folded further by the folding wall 143, almost 180° from the left half T1 of the tape T applied to the front side of the blank B.
• the right half T2 of the tape T that should be folded back is bent along the end wall 144 and the folding wall 143. Since the tape T is folded back by the end wall 144 that is slightly spaced from the end face E of the blank B, the tape is folded without touching the end face E of the lateral end of the blank B.
• the tape T is heat bonded in this state so that a small gap is formed between the end face E of the blank B and the tape T after the blank B has been processed.
• the end face E of the blank B not being touched refers to the possibility of a small gap forming between the end face E and the folded tape T.
• the phrase suggests that the length of the tape T from the lateral edge on the front side to the lateral edge on the back side of the blank B is greater than its length in the thickness direction of the end face E (i.e., the thickness of the blank B). Namely, the phrase includes the case where the floating tape T is partially in contact with the end face E.
• the left half T1 of the tape T heat bonded to the bonding end area A1 on the front side of the lateral end of the blank B is 4.7 mm wide
• the remaining right half T2 heat bonded to the bonding end area A2 on the back side is 4.7 mm wide.
• the portion opposite and not heat bonded to the end face E is 0.6 mm wide.
• the gap be "small” as described above; a relatively large gap may be formed between the end face E of the blank B and the tape T after the blank B has been processed in the end face tape application apparatus 100 according to this embodiment.
• the tape-folding system 140 uses a single passage 141 with a continuously varying inner wall structure to fold back the tape T.
• the tape-folding system 140 is not limited to the configuration in this embodiment and may use a plurality of stations to fold the tape step by step, or may fold the tape while transportation of the blank B is stopped rather than during its transport.
• the end face tape application apparatus 100 in this embodiment includes a heat-bonding system for applying the folded tape T to a bonding end area A2 on the back side of the blank B.
• the heat-bonding system includes a first heat-bonding unit 150 configured to tack the folded tape T to the bonding end area A2 on the back side of the blank B, and a second heat-bonding unit 160 configured to heat bond the entire surface of the folded tape T to the bonding end area A2 on the back side of the blank B.
• the first heat-bonding unit 150 is arranged near the exit of the passage 141 of the tape-folding system 140, and provided for tacking the folded tape T to the back side of the blank B to keep the tape T in the folded state as the blank is fed to the second heat-bonding unit 160.
• a portion of the right half T2 of the tape T may be heat bonded to the bonding end area A2 on the back side of the blank B, inside in the width direction (left and right direction in Fig. 10B ) perpendicular to the blank-conveying direction.
• a 2.2 mm-wide area along the free end of the tape T folded back onto the back side of the blank B (right end before being folded back), from the leading end to the trailing end in the blank-conveying direction may be heat bonded to the bonding end area A2 on the back side of the blank B.
• the first heat-bonding unit 150 includes a tape-correcting guide 155, which supports the tape T except for the region to be tacked to the back side of the blank B, and which maintains the folded state of the tape T that has been folded back by the tape-folding system 140 and forced to be positioned close to the other side of the blank B.
• the first heat-bonding unit further includes a stationary upper sealing bar 151 that heats the front side of the lateral end of the blank B, and a lower sealing bar 156 that is displaceable up and down and heats the back side of the lateral end of the blank B, both provided on the conveying path where the lateral end of the blank B passes.
• the tape-correcting guide 155 is a non-heating bar that supports and pushes up the tape T from below such as to face the upper sealing bar 151.
• the lower sealing bar 156 is adjacent the tape-correcting guide 155 and opposite the upper sealing bar 151.
• the tape-correcting guide 155 and the lower sealing bar 156 are spaced apart, for example, about 0.5 mm in the horizontal direction.
• the region with fine hatching inside the upper sealing bar 151 represents a portion opposite the left half T1 of the tape T (4.7 mm wide and 100 mm long in the blank-conveying direction).
• the region with fine hatching inside the lower sealing bar 156 represents a portion opposite the area of the right half T2 of the tape T that should be tacked (2.2 mm wide and 100 mm long in the blank-conveying direction).
• the tape-correcting guide 155 is stationary.
• the exit of the passage 141 of the tape-folding system 140 is substantially continuous with the space between the upper sealing bar 151 and the tape-correcting guide 155 in the first heat-bonding unit 150, so that the blank B can be transported to a predetermined heating point with the tape T maintained in the folded state.
• the tape-correcting guide 155 is a non-heating bar, the tape T is prevented from staying in contact with the sealing bar for a prolonged period, so that thermal contraction of the tape T can be minimized.
• the tape-correcting guide 155 is provided with a non-stick surface coating such as a fluorine resin coating on the surface that makes contact with the blank B or tape T to prevent the resin layer in the blank B or tape T from adhering to the tape-correcting guide 155.
• a non-stick surface coating such as a fluorine resin coating
• the blank B is paused at a predetermined position, and the lower sealing bar 156 is lifted, so that the lateral end of the blank B is held between the upper sealing bar 151 and the lower sealing bar 156, thus achieving tacking.
• the free end of the right half T2 of the tape T is heat bonded to the back side of the blank B, while the remaining part of the right half T2 of the tape T is not heat bonded to the blank B and is left floating.
• the lower sealing bar 156 is in the lowered position, the space between the upper sealing bar 151 and both the lower sealing bar 156 and tape-correcting guide 155 forms the conveying path for the lateral end of the blank B, allowing the blank B to pass through.
• the upper sealing bar 151 may be heated to, for example, 115°C
• the lower sealing bar 156 may be heated to, for example, 135°C.
• the lower sealing bar 156 is preferably heated to a higher temperature than that of the upper sealing bar 151 because the tape T is tacked to the back side of the lateral end of the blank B, and because some time has passed since the blank B was heated by the blank-heating system 110.
• the upper sealing bar 151 need not be heated to as high a temperature as the lower sealing bar 156 because the heat applied in the tape-tacking system 130 is still present.
• the tape T may adhere to the upper sealing bar 151 or the lower sealing bar 156. If such adhesion of the tape T is unlikely to occur, the temperature of the upper sealing bar 151 and the lower sealing bar 156 may be set higher.
• the upper sealing bar 151 and the lower sealing bar 156 are provided with a non-stick surface coating such as a fluorine resin coating on the surface that makes contact with the blank B or tape T to prevent the resin layer in the blank B or tape T from adhering to the sealing bars 151, 156.
• a non-stick surface coating such as a fluorine resin coating
• the method of heat bonding the tape T to the blank B in the first heat-bonding unit 150 is not limited to the one that uses sealing bars (heated plates). As long as the tape T can be tacked to the blank B, any of various known configurations can be adopted. For example, a heat-bonding method that uses a fixing roller, or a method that uses ultrasound, can be adopted. Depending on which method is adopted, the heat bonding may be performed while the blanks B are transported, instead of when the transportation of the blanks B is paused.
• the second heat-bonding unit 160 heat bonds approximately the entire surface of the folded tape T to the bonding end area A2 on the back side of the blank B. Since a portion of the right half T2 of the tape has been tacked to the back side of the blank B in the first heat-bonding unit 150, the tape T is maintained in the folded state without being guided by the tape-correcting guide.
• the second heat-bonding unit 160 in this embodiment heat bonds the entire surface of the right half T2 of the tape T facing the back side of the blank B, this is not a limiting condition. At least a floating part of the tape T that was not heat bonded to the back side of the blank B in the first heat-bonding unit 150 may be newly heat bonded here. A part of the tape may remain floating if it is to be melted in the heat-sealing process for forming the blank B into a paper container.
• the second heat-bonding unit 160 is configured with a stationary upper sealing bar 161 that heats the front side of the lateral end of the blank B, and a lower sealing bar 166 that is displaceable up and down and heats the back side of the lateral end of the blank B, both provided on the conveying path where the lateral end of the blank B passes.
• the regions with fine hatching inside the upper sealing bar 161 and the lower sealing bar 166 represent portions opposite the left half T1 and the right half T2 of the tape T that should be heat bonded (4.7 mm wide and 100 mm long in the blank-conveying direction).
• the lower sealing bar 166 With the blank B paused at a predetermined position, the lower sealing bar 166 is lifted, so that the lateral end of the blank B is held between the upper sealing bar 161 and the lower sealing bar 166, allowing the tape to be entirely heat bonded.
• the left half T1 of the tape T is heat bonded to the front side of the blank B
• the right half T2 of the tape T is mostly heat bonded to the back side of the blank B, i.e., the tape T is heat bonded to both the front and the back of the blank B, thus covering the end face E.
• the end face E of the blank B may be covered by the tape T directly heat bonded thereto, or may be covered by the tape T with a gap therebetween.
• the space between the upper sealing bar 161 and the lower sealing bar 166 forms the conveying path for the lateral end of the blank B, allowing the blank B to pass through.
• the upper sealing bar 161 may be heated to, for example, 40°C
• the lower sealing bar 166 may be heated to, for example, 130°C.
• the lower sealing bar 166 is preferably heated to a higher temperature because the tape T is heat bonded to the remaining part of the bonding end area A2 on the back side of the blank B.
• the upper sealing bar 161 need not be heated to as high a temperature as the lower sealing bar 166 because the heat applied in the previous systems is still present. If the temperature of the upper sealing bar 161 and the lower sealing bar 166 is too high, the tape T may adhere to the upper sealing bar 161 or the lower sealing bar 166. If such adhesion of the tape T is unlikely to occur, the temperature of the upper sealing bar 161 and the lower sealing bar 166 may be set higher.
• the upper sealing bar 161 and the lower sealing bar 166 are provided with a non-stick surface coating such as a fluorine resin coating on the surface that makes contact with the blank B or tape T to prevent the resin layer in the blank B or tape T from adhering to the sealing bars 161, 166.
• a non-stick surface coating such as a fluorine resin coating
• the method of heat bonding the tape T to the blank B in the second heat-bonding unit 160 is not limited to the one that uses sealing bars (heated plates). As long as the tape T can be tacked to the blank B, any of various known configurations can be adopted. For example, a heat-bonding method that uses a fixing roller, or a method that uses ultrasound, can be adopted. Depending on which method is adopted, the heat bonding may be performed while the blanks B are transported, instead of when the transportation of the blanks B is paused.
• the shape of the blank is not limited to the fan shape.
• the end face of any straight end portion of any part can be processed similarly. Some meandering, bulging, or notching in the edge of the end portion can be tolerated.
• the end face tape application apparatus has been described above as being designed to perform end face processing so as to ensure high water resistance of a finished paper container obtained from the blank. Instead, the apparatus can be used for various purposes, such as, for example, for covering an end face of a (straight) end of a sheet-like blank over the front and the back by applying a piece of tape.

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• 2023
  • 2023-09-21 CN CN202380090687.XA patent/CN120826314A/zh active Pending
  • 2023-09-21 EP EP23928730.3A patent/EP4684952A1/en active Pending
  • 2023-09-21 WO PCT/JP2023/034174 patent/WO2024195156A1/ja not_active Ceased
  • 2023-09-21 JP JP2025508110A patent/JP7757019B2/ja active Active

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