Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65B—MACHINES, APPARATUS OR DEVICES FOR, OR METHODS OF, PACKAGING ARTICLES OR MATERIALS; UNPACKING
  • B65B7/00—Closing containers or receptacles after filling
  • B65B7/02—Closing containers or receptacles deformed by, or taking-up shape, of, contents, e.g. bags, sacks
  • B65B7/025—Closing valve bags
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C65/00—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor
  • B29C65/02—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure
  • B29C65/10—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using hot gases (e.g. combustion gases) or flames coming in contact with at least one of the parts to be joined
  • B29C65/103—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using hot gases (e.g. combustion gases) or flames coming in contact with at least one of the parts to be joined direct heating both surfaces to be joined
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C66/00—General aspects of processes or apparatus for joining preformed parts
  • B29C66/01—General aspects dealing with the joint area or with the area to be joined
  • B29C66/05—Particular design of joint configurations
  • B29C66/10—Particular design of joint configurations particular design of the joint cross-sections
  • B29C66/11—Joint cross-sections comprising a single joint-segment, i.e. one of the parts to be joined comprising a single joint-segment in the joint cross-section
  • B29C66/112—Single lapped joints
  • B29C66/1122—Single lap to lap joints, i.e. overlap joints
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C66/00—General aspects of processes or apparatus for joining preformed parts
  • B29C66/40—General aspects of joining substantially flat articles, e.g. plates, sheets or web-like materials; Making flat seams in tubular or hollow articles; Joining single elements to substantially flat surfaces
  • B29C66/41—Joining substantially flat articles ; Making flat seams in tubular or hollow articles
  • B29C66/43—Joining a relatively small portion of the surface of said articles
  • B29C66/431—Joining the articles to themselves
  • B29C66/4312—Joining the articles to themselves for making flat seams in tubular or hollow articles, e.g. transversal seams
  • B29C66/43121—Closing the ends of tubular or hollow single articles, e.g. closing the ends of bags
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C66/00—General aspects of processes or apparatus for joining preformed parts
  • B29C66/40—General aspects of joining substantially flat articles, e.g. plates, sheets or web-like materials; Making flat seams in tubular or hollow articles; Joining single elements to substantially flat surfaces
  • B29C66/41—Joining substantially flat articles ; Making flat seams in tubular or hollow articles
  • B29C66/43—Joining a relatively small portion of the surface of said articles
  • B29C66/431—Joining the articles to themselves
  • B29C66/4312—Joining the articles to themselves for making flat seams in tubular or hollow articles, e.g. transversal seams
  • B29C66/43121—Closing the ends of tubular or hollow single articles, e.g. closing the ends of bags
  • B29C66/43123—Closing the ends of squeeze tubes, e.g. for toothpaste or cosmetics
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C66/00—General aspects of processes or apparatus for joining preformed parts
  • B29C66/70—General aspects of processes or apparatus for joining preformed parts characterised by the composition, physical properties or the structure of the material of the parts to be joined; Joining with non-plastics material
  • B29C66/71—General aspects of processes or apparatus for joining preformed parts characterised by the composition, physical properties or the structure of the material of the parts to be joined; Joining with non-plastics material characterised by the composition of the plastics material of the parts to be joined
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C66/00—General aspects of processes or apparatus for joining preformed parts
  • B29C66/70—General aspects of processes or apparatus for joining preformed parts characterised by the composition, physical properties or the structure of the material of the parts to be joined; Joining with non-plastics material
  • B29C66/73—General aspects of processes or apparatus for joining preformed parts characterised by the composition, physical properties or the structure of the material of the parts to be joined; Joining with non-plastics material characterised by the intensive physical properties of the material of the parts to be joined, by the optical properties of the material of the parts to be joined, by the extensive physical properties of the parts to be joined, by the state of the material of the parts to be joined or by the material of the parts to be joined being a thermoplastic or a thermoset
  • B29C66/739—General aspects of processes or apparatus for joining preformed parts characterised by the composition, physical properties or the structure of the material of the parts to be joined; Joining with non-plastics material characterised by the intensive physical properties of the material of the parts to be joined, by the optical properties of the material of the parts to be joined, by the extensive physical properties of the parts to be joined, by the state of the material of the parts to be joined or by the material of the parts to be joined being a thermoplastic or a thermoset characterised by the material of the parts to be joined being a thermoplastic or a thermoset
  • B29C66/7392—General aspects of processes or apparatus for joining preformed parts characterised by the composition, physical properties or the structure of the material of the parts to be joined; Joining with non-plastics material characterised by the intensive physical properties of the material of the parts to be joined, by the optical properties of the material of the parts to be joined, by the extensive physical properties of the parts to be joined, by the state of the material of the parts to be joined or by the material of the parts to be joined being a thermoplastic or a thermoset characterised by the material of the parts to be joined being a thermoplastic or a thermoset characterised by the material of at least one of the parts being a thermoplastic
  • B29C66/73921—General aspects of processes or apparatus for joining preformed parts characterised by the composition, physical properties or the structure of the material of the parts to be joined; Joining with non-plastics material characterised by the intensive physical properties of the material of the parts to be joined, by the optical properties of the material of the parts to be joined, by the extensive physical properties of the parts to be joined, by the state of the material of the parts to be joined or by the material of the parts to be joined being a thermoplastic or a thermoset characterised by the material of the parts to be joined being a thermoplastic or a thermoset characterised by the material of at least one of the parts being a thermoplastic characterised by the materials of both parts being thermoplastics
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C66/00—General aspects of processes or apparatus for joining preformed parts
  • B29C66/80—General aspects of machine operations or constructions and parts thereof
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C66/00—General aspects of processes or apparatus for joining preformed parts
  • B29C66/40—General aspects of joining substantially flat articles, e.g. plates, sheets or web-like materials; Making flat seams in tubular or hollow articles; Joining single elements to substantially flat surfaces
  • B29C66/41—Joining substantially flat articles ; Making flat seams in tubular or hollow articles
  • B29C66/43—Joining a relatively small portion of the surface of said articles
  • B29C66/431—Joining the articles to themselves
  • B29C66/4312—Joining the articles to themselves for making flat seams in tubular or hollow articles, e.g. transversal seams
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2023/00—Use of polyalkenes or derivatives thereof as moulding material
  • B29K2023/04—Polymers of ethylene
  • B29K2023/06—PE, i.e. polyethylene

Definitions

• Device for closing an opening consisting essentially of a tube section made of a thermoplastic
• the invention relates to a device for closing an opening consisting essentially of a thermoplastic, in particular polyethylene, in particular a filling opening in a packaging bag; with a hot air line and a * nozzle head connected to it.
• plastic sacks which are often made of a thermoplastic, such as polyethylene, are usually already folded and sealed, apart from a filling opening, which can also be arranged at the bottom of the sack, for example, before being filled onto a filling opening Filling machine to be filled with the respective bulk material through the filling opening.
• a filling opening which can also be arranged at the bottom of the sack, for example, before being filled onto a filling opening Filling machine to be filled with the respective bulk material through the filling opening.
• the filling opening of the plastic bag must be closed, this being particularly important in the case of air-sensitive goods or goods which should not be able to get into the environment when the filled plastic bag is transported later, whether for aesthetic or cost reasons to close the filling opening as hermetically as possible.
• the i.a. in the form of a tube section shaped filling is heated for this purpose and then closed by welding the opposing walls, in which the tube section is pressed between two clamping jaws.
• the inner wall of the hose section or the filling opening is usually heated by hot air, where a nozzle head is introduced into the opening, which nozzle head has a number of radially arranged air outlet openings directed towards the inner lateral surfaces of the opening.
• the heat energy introduced with the hot air softens the areas of the hose section or the filling opening which are acted upon by hot air and, after the generally axially displaceable nozzle head has been pulled back, is pressed together by pressing together other welded.
• the hose section to be sealed can additionally be sealed with a thermoplastic plastic film with a lower melting point than that of the other material from which the sack is made is made, lined
• the reason for the often poor quality of the weld seam closing the filling opening is, among other things, to be found in the fact that with conventional nozzle heads the heat cannot be introduced evenly enough into the areas of the inner jacket surfaces of the filling opening to be melted. This is mainly due to the fact that the diameter of a conventional nozzle head must be considerably smaller than the filling opening to be closed, since otherwise if the melted plastic came into contact with the nozzle head when it was pulled back, the filling opening and thus the entire sack would stick to the nozzle head.
• the temperature at the air outlet opening during processing of conventional polyethylene material is also due to the cooling which the hot air flow experiences when this distance is covered 250 to 300 ° C. Because of the associated, overall higher temperature level in the entire supply lines etc., it is evident that the radiation losses of the entire packaging machine are also significantly increased.
• the object of the invention is accordingly to improve a device of the type mentioned at the outset in such a way that the quality of the weld seam closing an opening of the type described in a packaging bag is improved and the power to be expended is reduced.
• the solution to the problem is characterized in a generic Vorrich device in that the nozzle head consists of at least two parts that are movable relative to each other.
• Another advantageous embodiment of the invention is characterized in that at least part of the nozzle head is mounted about an axis.
• a further advantageous embodiment of the invention is characterized in that the axis of the movable part of the nozzle head is arranged at right angles to the main axis of the nozzle head.
• a further advantageous embodiment of the invention is characterized in that the nozzle head has a plurality of air outlet openings which extend essentially radially from the main axis thereof.
• a further advantageous embodiment of the invention is characterized in that the air outlet openings are arranged essentially in a ring in one plane.
• Another advantageous embodiment of the invention is characterized in that the air outlet openings are arranged in a circumferential throat.
• a further advantageous embodiment of the invention is characterized in that at least one annular bead is arranged parallel to the air outlet openings arranged in a ring.
• a further advantageous embodiment of the invention is characterized in that the circumference of the nozzle head is variable in the area in which the air outlet openings are arranged.
• Another advantageous embodiment of the invention is characterized in that the nozzle head is axially movable overall in the direction of its main axis.
• nozzle head has an essentially cylindrical basic shape.
• a further advantageous embodiment of the invention is characterized in that the substantially cylindrical nozzle head consists of (at least two) parts, the cross section of which is essentially a sector of a circle, the central angle of which is reversed according to the number of parts of the nozzle head is a proportional part of a full circle.
• Another advantageous embodiment of the invention is characterized in that the substantially cylindrical nozzle head at one end adjoins the area of the - 6 -
• it has at least one ramp-shaped extension arranged at the end of the nozzle head facing away from the area of the air outlet openings, and a stop projecting in the direction of movement thereof when the nozzle head is axially moved.
• Another advantageous embodiment of the invention is characterized in that the stop has a rotatably mounted roller.
• nozzle head consists essentially of three parts, two of which are pivotable about axes arranged in the third (middle) part.
• Another advantageous embodiment of the invention is characterized in that the third component has essentially the shape of two interconnected plates, the (inner) distance from each other corresponds to the width of the other two parts, and that the axes of rotation of the other two parts are at right angles Plate to plate are arranged kendend.
• this has at least one pressure plate coated with an elastic material.
• this has at least one pressure plate provided with an edge with a small radius of curvature.
• a nozzle head In a preferred embodiment of a nozzle head according to the invention, it has two parts arranged opposite one another, each of which can be rotated about an axis are mounted and each have at one end a ramp-like extension which, when the nozzle head moves axially, abuts a stop, whereupon the parts in question are spread apart like a beak. Due to the beak-like spreading of the nozzle head, it is enlarged as it were and comes to rest on the inner wall of the filling opening to be closed.
• the air outlet openings which are preferably arranged in the form of a circular ring, are not closed and so that the melting plastic does not adhere to the nozzle head, provision can be made to arrange the air outlet openings in a circumferential throat. Parallel to the throat, a ring bead sealing towards the inside of the bag can be provided.
• the ring bead By means of a second, on the other side of the throat, i.e. thus facing away from the inside of the bag, the ring bead, the diameter of which is preferably slightly smaller than the diameter of the first ring bead, so that an annular gap remains between the inner wall of the opening to be closed and the second ring bead, ka with appropriate dimensioning of the diameter of the two mentioned, generally. that is, the ring bead lying on top and the dimensioning of the remaining ring gap connected therewith, the flow resistance of the entire arrangement of the nozzle head / filling opening, so that the amount of air escaping at a certain operating pressure can be determined.
• the pressure jaws required for pressing the heated walls can be designed differently.
• a first pressure jaw can be coated with an elastic material, for example foam rubber, whereas the second pressure jaw, which is the counterpart, has a comparatively sharp edge with a small radius of curvature. In this way a high * surface pressure is achieved in the heated area to be welded.
• FIG. 1 is a two-part nozzle head of a device according to the invention and the associated stops partially in section,
• FIG. 2 shows a view of a three-part nozzle head according to the invention with the associated stops
• FIG. 3 shows the same view of a three-part nozzle head according to the invention, partly in section, a pivotable part having been omitted for the sake of clarity,
• Fig. 4 is a side view of the same nozzle head partially in section
• Fig. 5 is a plan view of the same nozzle head, partially in cross section, with another part shown in Fig. 3 has been omitted.
• a device has a variant of a nozzle head 1, which consists of two mirror-symmetrical halves or parts 2 and 3.
• the part 3 is rotatably supported about an axis 4. axis not shown here.
• the entire shape of the nozzle head is approximately cylindrical, the cross section of a part 2 or 3 being essentially a semicircle.
• the nozzle head merges into a cone 5.
• the air outlet holes 7 are via channels 8 with - 10 -
• Cavity 9 connected, which is connected via a schematically illustrated connecting piece 10 to a hot air line (not shown) and from which hot air is applied.
• the upper end - both parts 2 and 3 each have a ramp-shaped extension 11. If the entire nozzle head is moved axially in the direction of arrow 12, the ramp-shaped extensions 11 come into engagement with stops 13, which can optionally also be designed as a rotatably mounted roller. In further movements of the nozzle head in the direction of arrow 12, the halves 2 and 3 rotate about their respective axes, the nozzle head being spread out at its lower end in the direction of the arrows 14 in a beak-like manner.
• the halves 2 and 3 lie with an annular bead 15 located at the respective lower end parallel to the throat 6 on the wall 16 of the filling opening to be closed, which is shown here in an idealized manner.
• the hot air flowing through the cavities 9 and the respective channels 8 and exiting at the outlet openings 7 reaches an annular gap 17 formed between the wall 16 and the fillet 6, where it is swirled and releases its heat to the cold wall 16.
• the air can escape in a controlled manner through a gap 19, which is also circular and is formed between a second annular bead 18 and the wall 16.
• a disadvantage of this nozzle head which is distinguished by its simple structure, is that due to the gap remaining between the two halves or parts 2 and 3 in a spread state, part of the wall of the filling opening to be heated is not directly exposed to hot air . This defect can be remedied by a somewhat more complex construction of the nozzle head according to the invention, as shown in FIG. 11 -
• the nozzle head 20 shown in FIG. 2 is characterized by a three-part construction, two outer parts 2 ′ and 3 ′, which are arranged as it were pursuela, are each pivotably attached to a central part 21 about an axis or 4 ′′.
• the mode of operation is completely analogous to the exemplary embodiment of a nozzle head according to the invention or a device according to the invention for closing an opening of the type mentioned in FIG. 1.
• a vertical nozzle head as shown in FIG by a suitable choice of the center of gravity of the parts 2 'or 3' can be achieved that these when moving back the nozzle head 20, in the opposite direction to the arrow 12, return to their original position under the influence of gravity.
• FIG. 2 The inner structure of the three-part nozzle head shown in FIG. 2 is shown in more detail in FIGS. 3, 4 and 5, with the wing 2 'being omitted for the sake of clarity and the wing 3' being drawn in the folded position.
• the nozzle head 20 consists of an upwardly extending middle part 21 which essentially has the basic geometrical shape of two plates 23 and 24 which are connected to one another in a region 22.
• the swing-out wings 3 'or the wing 2', not shown here, are arranged between these plates.
• the hot air flows through the bore 25 into the cavity 9 'formed by the individual components 2', 3 'and 21, and from there through the channels 8' to the outlet openings 7 arranged in a ring 6 in a throat.
• the air outlet opening 7 of a wing 3 ' must be arranged vertically at an angle such that the entirety of all the air outlet openings when the wings 2' or 3 'are folded out lie approximately in one plane.
• the inventive design of a device for closing an opening in packaging material made of thermoplastic materials increases the quality of the weld seam closing the opening, while at the same time reducing the power to be used and thus the costs.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Package Closures (AREA)

Priority Applications (2)

Applications Claiming Priority (2)

Publications (1)

Family

ID=6368765

Family Applications (1)

Country Status (6)

Cited By (1)

Families Citing this family (3)

Citations (6)

Family Cites Families (1)

• 1988
  • 1988-12-09 DE DE3841450A patent/DE3841450A1/de active Granted
• 1989
  • 1989-10-18 EP EP89250059A patent/EP0373731A1/de not_active Withdrawn
  • 1989-12-06 WO PCT/DE1989/000760 patent/WO1990006260A1/de not_active Ceased
  • 1989-12-06 JP JP2500502A patent/JPH0776020B2/ja not_active Expired - Lifetime
  • 1989-12-06 BR BR898907222A patent/BR8907222A/pt unknown
  • 1989-12-06 AU AU46555/89A patent/AU4655589A/en not_active Abandoned

Patent Citations (6)

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