Classifications

• • 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
  • B65D1/00—Rigid or semi-rigid containers having bodies formed in one piece, e.g. by casting metallic material, by moulding plastics, by blowing vitreous material, by throwing ceramic material, by moulding pulped fibrous material or by deep-drawing operations performed on sheet material
  • B65D1/02—Bottles or similar containers with necks or like restricted apertures, designed for pouring contents
  • B65D1/0223—Bottles or similar containers with necks or like restricted apertures, designed for pouring contents characterised by shape
  • B65D1/0261—Bottom construction
  • B65D1/0276—Bottom construction having a continuous contact surface, e.g. Champagne-type bottom

Definitions

• Container comprising a vaulted bottom with a star section
• the invention relates to containers obtained by blow molding or stretching from blanks (preforms or intermediate containers having undergone one or more prior blowing operations) of plastic.
• the blow-molding of a container comprises a step of introducing, into a mold in the impression of the container, a blank previously heated to a temperature greater than the glass transition temperature of the material constituting the preform (such as than PET), and a step of injection into the blank of a fluid (such as air) under pressure. Stretching by means of a sliding rod can complete the blowing.
• blowing difficulties (called “blowing” capacity of the container to be formed by blowing, that is to say, the capacity of the material to marry properly the mold cavity) because the thickness of the material makes it difficult to creep into the cavities of the mold corresponding to the ribs.
• Another solution is to push back the constituent material of the bottom of the container, using for this, inter alia, a special mold equipped with a mold bottom movable in translation which pushes the material (see in particular the European patent EP 1 069 983).
• the repoussage induces an increase in the rate of deformation of the material and therefore a mechanical increase in its crystallinity, the repoussage phase conferring on the bottom of the container its final shape.
• boxing does not guarantee that the rigidity of the bottom will be sufficient and does not exonerate the manufacturers to resort to particular forms that remain subject to the constraints of blowing.
• a plastic container comprising a body extending along a main axis and a bottom in the extension of the body of a lower side thereof, the bottom comprising:
• a conical arch which extends from a neighborhood of the seat towards the interior of the container to a central summit, this arch having in cross section a star-shaped profile inscribed between two circles whose diameter ratio is greater than or equal to
• This bottom offers both good structural rigidity and good blowing, while not requiring additional material, to the benefit of the lightness of the container.
• the ratio of the diameters is between 0.8 and 0.9;
• the vault comprises a series of facets defining between them obtuse angles in a transverse plane;
• the angles between facets are greater than or equal to 100 °;
• the vault has two superimposed portions, namely a substantially conical lower portion at an acute angle, which extends from the vicinity of the seat to an intermediate zone of junction, and a substantially conical upper section with an obtuse angle, which extends from the intermediate junction zone to the summit;
• the lower portion and the upper portion of the vault have equivalent or substantially equivalent axial extensions
• the lower portion of the arch has, in axial section, a curved profile concavity facing towards the axis of the container;
• the upper portion of the arch has, in axial section, a curved profile concavity turned away from the axis of the container. ; in axial section, the profiles of the lower portion and of the upper portion have respective radii of curvature
• the roof has a height H measured axially and the seat has a width d measured transversely, the H / d ratio of these dimensions being greater than 0.25.
• Figure 1 is a perspective view from below of a plastic container, according to a first embodiment
• Figure 2 is a perspective view, on an enlarged scale, of the bottom of the container of Figure 1;
• Figure 3 is a plan view, from below, of the bottom of Figure 2;
• FIG. 4 is a section of the bottom of the container of the preceding figures, according to the sectional plane IV-IV of Figure 3;
• Figure 5 is a section along the sectional plane V-V of Figure 4.
• Figure 6 is a view similar to Figure 2, illustrating a container bottom according to a second embodiment
• Figure 7 is a plan view, from below, of the bottom of Figure 6;
• Figure 8 is a section along the section plane VIII-VIII of Figure 7;
• Figure 9 is a section along the IX-IX section plane of Figure 8.
• Figure 10 is a section along the X-X section plane of Figure 8.
• Figure 1 a container 1 made by stretching blow from a thermoplastic preform such as PET (polyethylene terephthalate).
• a thermoplastic preform such as PET (polyethylene terephthalate).
• This container 1 comprises a body 2 of generally cylindrical shape around a main axis X.
• the body 2 is extended at an upper end by a neck 3 forming a rim and, at a lower end, by a bottom 4.
• the bottom 4 comprises a seat 5 in the form of an annular bead (in this case O-ring) which extends in the extension of the body 2 and ends axially by a continuous annular face which forms the lower end of the container and defines a laying plane 6 perpendicular to the axis X of the container 1, by which it can rest stably on a flat surface such as a table.
• a seat 5 in the form of an annular bead (in this case O-ring) which extends in the extension of the body 2 and ends axially by a continuous annular face which forms the lower end of the container and defines a laying plane 6 perpendicular to the axis X of the container 1, by which it can rest stably on a flat surface such as a table.
• D is the overall width, measured transversely, of the body 2.
• this width D overall corresponds to a diameter.
• the laying plane 6 extends radially over a width denoted d which, in the illustrated examples where the container 1 is symmetrical with revolution, corresponds to a diameter.
• the seat 5 is connected externally to the body 2 by a fillet 7 with large radius; the diameter d of the laying plane 6 and the overall diameter D of the body are preferably in a ratio of between 0.65 and 0.9. In the example shown, this ratio is about 0.7:
• the seat 5 Towards the inside of the container 1, the seat 5 is connected, by an annular cheek 8 in the form of a short radius fillet, to a membrane 9 conical open-angle angle (in the illustrated examples, this angle is about 135 °) and having a small radial extension.
• the bottom 4 further comprises a conical arch 10 extending from an inner edge 11 of the membrane 9 inwardly of the container 1 to a central apex 12. From the inner edge 11 of the membrane 9 (which, given the small radial extension of the membrane 9, remains in the vicinity of the seat 5) to the top 12, the roof 10 has a cross section (perpendicular to the axis ) a starry profile.
• this star-shaped profile is inscribed between an inner circle 13 (virtual) and an outer circle 14 (virtual) having respective diameters D1 and D2 whose ratio is greater than or equal to 0 7. According to a preferred embodiment illustrated in the figures, this ratio is between 0.8 and 0.9:
• the star formed by the profile (in cross section) of the vault 10 has branches 15 whose radial extension is small compared to the radius (or diameter) overall of the star.
• the vault 10 thus comprises a series of facets 16 which, grouped in pairs, define the branches 15 of the star.
• the angles between the facets 16 of the same branch 15, and between two adjacent facets 16 of two adjacent branches, measured in a transverse plane and noted respectively A and B ( Figure 5), are preferably obtuse.
• angles A, B are advantageously greater than or equal to 100 °.
• angles A and B are about 100 ° and 150 °, respectively.
• the roof 10 has an axial extension (or height), measured axially between the seat 5 and the top 12, denoted H.
• H axial extension
• the roof 10 is advantageously deep, that is to say that the height H of the vault is not negligible compared to the diameter d of the seat 5, the H / d ratio being greater than 0.25. In the illustrated examples, this ratio is about 0.3.
• FIGS. 1-10 In a first exemplary embodiment, illustrated in FIGS.
• the vault 10 is unitary and extends continuously from the membrane 9 to the top 12.
• the arch 10 preferably has, in axial section (FIG. 4), a concavely curved profile turned towards the axis X of the container 1.
• the radius of curvature of the arch denoted R0, is greater than or equal to equal to the seating diameter:
• the vault 10 has an acute average angle C at the top, between 70 ° and 90 °. In the example illustrated (see FIG. 4), this average angle C at the vertex is about 80 °.
• FIGS. 1-10 In a second exemplary embodiment, illustrated in FIGS.
• the vault 10 is stepped and comprises two superimposed portions, namely a lower portion 17 on the side of the seat 5, and an upper portion 18 on the side of the top 12.
• the lower portion 17 and the upper portion 18 both have in section a star-shaped profile inscribed between an inner circle 13 and an outer circle 14 having respective diameters D1 and D2 whose ratio D1 / D2 is greater than 0.7. ( Figures 9 and 10).
• the lower portion 17 extends from the inner edge 11 of the membrane 9 (in the vicinity of the seat 5) to an intermediate joining zone 19 located at approximately mid-height of the roof 10, and the upper portion 18 extends from the intermediate junction zone 19 to the top 12 of the vault 10.
• the lower portion 17 is substantially conical at an acute angle E at the vertex, this angle E at the vertex being preferably between 40 ° and 60 °, and for example about 50 °, as illustrated in FIG. 8.
• the upper portion 18 is, in turn, substantially conical at an angle F obtuse at the top, this angle F at the vertex is preferably between 100 ° and 120 °, and for example about 110 °, as shown in FIG. 8.
• the intermediate junction zone 19 (where a juncture between the lower portion 17 and the upper portion 18) is located approximately halfway up the vault 10, the lower portion 17 and the upper portion 18 have axial extensions (or heights), respectively denoted H1 and H2, equivalent or practically equivalent, such that:
• the lower portion 17 has, in axial section, a concavely curved profile turned in the direction of the axis X of the container 1, whereas the upper portion 18 has, in axial section a concave curved profile turned away from the X axis.
• the concavity of the vault 10 is reversed between the lower portion 17 and the upper portion 18 at their intermediate zone 19. junction.
• the lower portion 17 and the upper portion 18 preferably have respective radii of curvature, denoted R1 and R2, which are of the same order of magnitude and are comparable to the radius of the laying plane.
• the radii R1 and R2 are not of the same order of magnitude, but that R1 may be less than or equal to R2.
• the radii R1 and R2 are for example in a ratio between 0.6 and 1:
• This arch 10 gives the bottom 4 a good compromise between blowing and resistance to deformation.
• the star shape of the vault 10 makes it possible to obtain a good axial stiffness, that is to say a good resistance to compression along the X axis, the 16 angular facets acting at the stiffening manner and opposing a reversal of the vault 10 under the effect of the pressure in the container 1.
• the inversion of curvature in the stepped vault gives the latter the advantage of greater blowing, thanks to a lesser quantity of material necessary for its production.
• Tests have thus demonstrated that a container having the vault 10 described above can be manufactured with a much lower blowing fluid pressure than that required for a container with vaults according to the prior art. More specifically, while a mean blowing pressure of between 35 and 38 bar was necessary to make a vault container of equivalent strength, the container 1 provided with the vault 10 described above can be made by injecting a fluid into a container. blowing pressure of the order of 24 bar, which represents a reduction of 30% to 40%. This results in lower requirements for blowing fluid and it becomes possible to employ smaller pressurized fluid production facilities.
• the manufacture of the bottom 4 of the container 1 may advantageously be carried out by implementing a boxing technique, in which the mold in which the container 1 is formed has a movable mold bottom which makes it possible to overstretch the material at the bottom 4 , with the benefit of a good impression and a higher degree of crystallinity (favorable to the structural rigidity of the bottom).
• the container 1 is particularly suitable for filling carbonated beverages, especially beer.

Landscapes

• Engineering & Computer Science (AREA)
• Ceramic Engineering (AREA)
• Mechanical Engineering (AREA)
• Containers Having Bodies Formed In One Piece (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (2)

Family

ID=46754570

Family Applications (1)

Country Status (7)

Families Citing this family (12)

Family Cites Families (15)

• 2012
  • 2012-04-17 FR FR1253543A patent/FR2989356B1/fr not_active Expired - Fee Related
• 2013
  • 2013-04-10 CN CN201380009965.0A patent/CN104136329B/zh active Active
  • 2013-04-10 MX MX2014010087A patent/MX350909B/es active IP Right Grant
  • 2013-04-10 US US14/374,699 patent/US9598201B2/en active Active
  • 2013-04-10 PL PL13719993T patent/PL2785603T3/pl unknown
  • 2013-04-10 WO PCT/FR2013/050773 patent/WO2013156710A1/fr not_active Ceased
  • 2013-04-10 EP EP13719993.1A patent/EP2785603B1/de active Active

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events