Classifications

• • 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
  • B29C45/00—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
  • B29C45/17—Component parts, details or accessories; Auxiliary operations
  • B29C45/40—Removing or ejecting moulded articles
  • B29C45/44—Removing or ejecting moulded articles for undercut articles
  • B29C45/4407—Removing or ejecting moulded articles for undercut articles by flexible movement of undercut portions of the articles
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65D—CONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS, e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES, DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; PACKAGING ELEMENTS; PACKAGES
  • B65D41/00—Caps, e.g. crown caps or crown seals, i.e. members having parts arranged for engagement with the external periphery of a neck or wall defining a pouring opening or discharge aperture; Protective cap-like covers for closure members, e.g. decorative covers of metal foil or paper
  • B65D41/32—Caps or cap-like covers with lines of weakness, tearing-strips, tags, or like opening or removal devices, e.g. to facilitate formation of pouring openings
  • B65D41/34—Threaded or like caps or cap-like covers provided with tamper elements formed in, or attached to, the closure skirt
  • B65D41/3461—Threaded or like caps or cap-like covers provided with tamper elements formed in, or attached to, the closure skirt the tamper element being retracted by heat or by heat and pressure
  • B65D41/3466—Threaded or like caps or cap-like covers provided with tamper elements formed in, or attached to, the closure skirt the tamper element being retracted by heat or by heat and pressure and being integrally connected to the closure by means of bridges
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
  • B29L2031/00—Other particular articles
  • B29L2031/56—Stoppers or lids for bottles, jars, or the like, e.g. closures
  • B29L2031/565—Stoppers or lids for bottles, jars, or the like, e.g. closures for containers

Definitions

• the invention relates to a closure cap for a container according to the preamble of claim 1 and to a device for producing a plastic closure cap according to the preamble of claim 5.
• the guarantee band has a tendon-like reinforcement on the inside, which has the purpose of improving the flow behavior of the thermoplastic composition during the injection process.
• the shrinking of the guarantee band onto the container neck by the action of heat is to be facilitated thereby.
• the reinforcement on the inside of the guarantee band can only be dimensioned to a limited extent, since the dimensions and the configuration of the container neck must be taken into account.
• problems still occurred when the cap was removed from the mold in an axially opening tool but these are not directly related to the reinforcement on the guarantee band.
• forces occur on the guarantee band which act opposite to the direction of ejection and which pull the guarantee band down.
• undesirable stretching occurs at the predetermined breaking connecting webs, since the thermoplastic is still relatively warm and stretchable immediately after the spraying process.
• the guarantee band can be deformed during demolding in such a way that it can no longer be properly engaged with the neck of the container.
• the reinforcement By arranging the material reinforcement on the outside of the guarantee band, the reinforcement can, if necessary, be dimensioned larger than would be possible with a reinforcement on the inside of the guarantee band.
• the material reinforcement also serves as a wiping aid in the injection molding tool, in that the guarantee band itself is held in the mold by the material reinforcement during a relative movement of the internal mandrel.
• the enlargement of the cross-section of the material reinforcement against the lower edge of the guarantee band means that the guarantee band is supported on the tool when it is stripped from the inner mandrel, but that it is nevertheless not unnecessarily difficult to eject the closure cap in the opposite direction.
• Gru ⁇ driss has and extends over a sector that is equal to or less than half of the sector between two predetermined breaking links. In certain applications it can also be advantageous if the reinforcement has an approximately triangular plan, one side of the triangle running approximately parallel to the lower edge of the guarantee band.
• Another object of the invention is to provide a device for producing a closure cap of the type mentioned at the outset, which is simple to manufacture and produces defect-free closure caps at high output rates.
• This object is achieved with a device which has the features of claim 5.
• the material recesses can be made relatively easily on already existing injection molding tools, so that surprising improvements can be achieved both on the injection molding tool itself and on the closure cap by a relatively simple measure.
• FIG. 1 shows a partial cross section through a closure cap according to the invention in a tenfold enlargement
• FIG. 2 shows a partial view from below of the closure cap according to FIG. 1,
• FIG. 3 shows a side view of a reinforcement on the guarantee band
• FIG. 4 shows a modified exemplary embodiment of a reinforcement on the guarantee band
• FIG. 5 shows the closure cap according to FIG. 1 in the closed injection molding tool
• a sealing cap 1 As shown in FIG. 1, a sealing cap 1, as is known per se, has a guarantee band 2, which is connected in one piece to the lower edge 4 of the sealing cap via predetermined breaking connecting webs 3.
• the closure cap shown also has an internal thread 7 for screwing onto a container mouth with an external thread, as well as a sealing lip 8 and an inner seal 9.
• the closure cap can also have a different configuration.
• the guarantee band 2 is intended to be brought into engagement with a bead on the container neck, so that when the closure cap 1 is screwed on, the predetermined breaking connecting webs 3 tear and a first-time opening of the closure cap is indicated.
• the guarantee band is shrunk onto the neck of the container by the action of heat.
• the configuration of the guarantee band can also be modified such that it snaps onto the container on the container neck without the action of heat when the closure cap is screwed on.
• the configuration of the reinforcement 5 on the outside 6 of the guarantee band can be seen from FIGS. 1, 2 and 3.
• the cross-section of the reinforcement increases in a bead-like manner towards the lower edge 10 of the guarantee band and has a wedge shape which is rounded at the bottom, the wedge angle of the reinforcement 5 being substantially larger than the wedge angle ⁇ (of the guarantee band 2 as shown).
• the one with the reinforcement 5 additional support effect achieved in the injection molding tool is shown in FIG.
• the reinforcements 5 appear as segment-like projections which can be supported on the tool, as can be seen in particular from FIG.
• the floor plan of the reinforcement can be rectangular or approximately triangular, as shown in FIG. 4.
• the triangles can be designed in such a way that their tips almost touch below the sol break connecting webs 3.
• the reinforcements with a rectangular plan advantageously extend over a sector A, which is equal to or smaller than half of sector B between two predetermined breaking connecting webs 3.
• FIG. 5 shows the separation levels of the different tool parts in the area of the guarantee band.
• the upper tool part 11 defines the outer contour of the closure cap 1.
• the lower tool part 12 forms the lower edge 4 of the closure cap and the outside 6 of the guarantee band 2.
• the lower tool part 12 has an inner wall 17 which is located at the wedge angle of the guarantee band flared downwards.
• the parting plane 13 between the upper tool part 11 and the lower tool part 12 lies on the level of the lower edge 4 of the closure cap 1.
• the inner contour of the closure cap is formed by an inner tool part 14, which also forms the inside 15 of the guarantee band and defines the lower edge 10 of the guarantee band.
• the guarantee band 2 in turn is supported separately by the reinforcements 5, which are formed by material recesses 16 in the lower tool part 12.
• the forces on the guarantee band that arise as a result of static friction when the tool parts are opened can no longer cause the predetermined breaking connecting webs 3 to be stretched or the guarantee band 2 to be deformed.
• OMPI Reinforcements 5 a homogeneous intermeshing of the casting compound in the area between two predetermined breaking connecting webs.
• FIGS. 6 to 11 show the individual relative positions of the tool parts when the molded closure cap is removed from the mold. Details of such an injection molding tool are known to the person skilled in the art and are therefore not explained in more detail here.
• the movements of the individual tool parts are effected with a hydraulic step ejector 18.
• FIG 9 shows the crucial demolding phase, in which the guarantee tape is demolded.
• the upper tool part 12 is raised further, so that the closure cap is stripped from the inner tool part 14 together with the guarantee band.
• the guarantee band is supported on the reinforcements or on the material recesses as shown in FIG. After completion of this phase, the closure cap 1 is only held by the lower tool part 12.
• a plunger 19 is extended, which ejects the cap, as shown in Figure 10.
• the ram 19 is preferably actuated pneumatically. After the sealing cap has been ejected, the individual tool parts move back into their original position, so that the mold can be closed for a further injection process.
• FIG. 11 shows the tool in which only the upper tool part 11 has to be closed.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Manufacturing & Machinery (AREA)
• Closures For Containers (AREA)
• Moulds For Moulding Plastics Or The Like (AREA)
• Making Paper Articles (AREA)
• Auxiliary Devices For And Details Of Packaging Control (AREA)
• Closing Of Containers (AREA)
• Injection Moulding Of Plastics Or The Like (AREA)

Priority Applications (1)

Applications Claiming Priority (1)

Publications (1)

Family

ID=4178898

Family Applications (1)

Country Status (10)

Cited By (1)

Families Citing this family (20)

Citations (3)

Family Cites Families (3)

• 1982
  • 1982-12-23 JP JP58500217A patent/JPS58502165A/ja active Granted
• 1983
  • 1983-12-28 EP EP83810623A patent/EP0113642B1/de not_active Expired
  • 1983-12-28 US US06/638,476 patent/US4564112A/en not_active Expired - Fee Related
  • 1983-12-28 DE DE8383810623T patent/DE3367893D1/de not_active Expired
  • 1983-12-28 WO PCT/CH1983/000149 patent/WO1984002694A1/de unknown
  • 1983-12-28 AT AT83810623T patent/ATE23834T1/de not_active IP Right Cessation
  • 1983-12-28 AU AU23312/84A patent/AU567534B2/en not_active Ceased
• 1984
  • 1984-01-05 ES ES1984289057U patent/ES289057Y/es not_active Expired
  • 1984-01-06 ZA ZA84112A patent/ZA84112B/xx unknown
  • 1984-01-06 NZ NZ206766A patent/NZ206766A/en unknown

Patent Citations (4)

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