Flat-bottomed plastics container

Abstract

A container made of plastics material, provided with a body and with a bottom in the continuation of the body at a lower end of the body. The bottom has an oblong curved contour and includes a seating surface forming a standing plane of the container. In example embodiments, the standing plane has an oblong closed curved shape extending along a longitudinal median axis and a transverse median axis. In example embodiments, the standing plane has an arch extending from the seating surface as far as a central zone of the bottom, the arch delimiting a concavity oriented toward the outside of the container.

Claims

1. A container (1) made of plastics material, provided with a body (11) and with a bottom (12) in the continuation of the body (11) at a lower end of the body (11), the bottom (12) having an oblong curved contour and comprising: a seating surface (21) forming a standing plane (210) of the container, the standing plane having an oblong curved shape extending along a longitudinal median axis (ML) and a transverse median axis (MT), the seating surface (21) having a width (W), with a value w, between its distal ends along the transverse median axis (MT) wherein the standing plane (210) is not closed, the seating surface (21) having two narrowed portions situated at the ends of the seating surface along the longitudinal median axis (ML); an arch (22) extending from the seating surface (21) as far as a dome (5) of a central zone (23) of the bottom (12), the arch (22) delimiting a concavity from the outside of the container (1); the container (1) having a central axis (C) on which the central zone (23) is centered, wherein: the seating surface (21) has width reductions that are each situated on opposing sides of the longitudinal median axis (ML), at least at the intersection between the seating surface (21) and the transverse median axis (MT), and the arch (22) has, for each width reduction of the seating surface (21), for the one part, an indentation (4) forming said width reduction of the seating surface (21) and forming a concavity from the outside of the container (1), and, for the other part, a curved portion (220) extending directly from said indentation (4) in the direction of the central zone (23), and having, in a section plane passing through the central axis (C) and the transverse axis (MT), a section in the form of a circular arc inscribed in a circle (Cc), the center of which is situated at a distance (DC), with a value dc, from the central axis (C) along the transverse median axis (MT), with 10% w?dc?30% w.

2. The container (1) as claimed in claim 1, wherein the bottom (12) of the container (1) exhibits planar symmetry on a first plane in which the transverse median axis (MT) and the central axis (C) of the container (1) are inscribed, and planar symmetry on a second plane in which the longitudinal median axis (ML) and the central axis (C) of the container (1) are inscribed.

3. The container (1) as claimed in claim 1, wherein each curved portion (220) has a granular texture.

4. The container (1) as claimed in claim 1, wherein: each indentation (4) has a length (E), with a value e, along the longitudinal median axis (ML); the seating surface (21) has a length (T), with a value t, between its distal ends along the longitudinal median axis (ML); with 65% t?e?75% t.

5. The container (1) as claimed in claim 1, wherein the seating surface (21) has a width, with a value w, between the distal ends of the seating surface along the transverse median axis (MT), and wherein the dome (5) has a width, with a value y, centered between the distal ends of the seating surface along the transverse median axis (MT), with 30% w?y?45% w.

6. The container (1) as claimed in claim 1, wherein the seating surface (21) has a length, with a value t, between its distal ends along the longitudinal median axis (ML), and wherein the dome (5) has a length, with a value x, centered between the distal ends along the longitudinal median axis (ML), with 25% t?x?70% t.

7. A mold for manufacturing a container (1) by blow-molding or stretch-blow-molding a blank made of plastics material, the mold comprising a mold bottom having an upper molding surface which corresponds to an impression of the bottom (12) of the container (1) as claimed in claim 1.

8. The container (1) as claimed in claim 1, wherein the circle (Cc) has a radius (Rc) which may be equal to around 5.6 mm.

9. The container (1) as claimed in claim 1, wherein the curved portions (220) are inscribed in trapezoids, the short bases of which are oriented toward the central zone and the long bases of which are oriented toward the indentations (4).

10. The container (1) as claimed in claim 1, wherein the dome (5) of the bottom (12) comprises the profile of which, parallel to the standing plane, is an elongate oblong shape along the axis (ML) and which creates, from the outside of the container (1), a concavity in the arch (22).

11. The container (1) as claimed in claim 10, wherein in a median transverse section of the bottom (12) passing through the central axis (C), each curved portion (220) has an initial portion (221) adjacent to the dome (5) and a terminal portion (222) adjacent to the seating surface (21).

12. The container (1) as claimed in claim 11, wherein, at its junction with the dome (5), the initial portion (221) extends parallel to the transverse median axis (MT).

13. The container (1) as claimed in claim 11, wherein a tangent to the terminal portion (222) forms, for its part, at the intersection of said terminal portion (222) with the seating surface (21), an angle (?), with a value a, with a straight line perpendicular to the transverse median axis (MT) and inscribed in a median plane of the bottom (12) in a transverse section of the bottom (12), with 12.5??a?35?.

14. The container (1) as claimed in claim 10, wherein the dome (5) has, along the longitudinal median axis (ML), a maximum length (X), with a value x; along the transverse median axis (MT), a maximum width (Y), with a value y, with 2 y?x?3.5 y, preferably with x=2.4 y.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further features and advantages of the invention will become more clearly apparent from reading the following description of various embodiments of the invention, which are given by way of nonlimiting illustrative examples, and from the appended drawings, in which:

(2) FIG. 1 is a schematic depiction showing a view in longitudinal section of a bottom of a container according to the prior art;

(3) FIG. 2 is a perspective depiction of a flat container according to a first embodiment, showing an inset with a detail on an enlarged scale, illustrating more specifically a bottom of the container;

(4) FIG. 3 is a view in longitudinal section of the bottom of the container of the first embodiment;

(5) FIG. 4 is a view from below of the bottom according to the first embodiment;

(6) FIG. 5 is a view from below of the bottom of a second embodiment, in which the bottom is provided with branches;

(7) FIG. 6 is a view in section on a longitudinal plane of the bottom of the second embodiment;

(8) FIG. 7 is a view in section on a transverse plane of the bottom of the second embodiment;

(9) FIG. 8 is a perspective view of the bottom of the second embodiment comprising an inset with a detail on an enlarged scale, illustrating more specifically a branch of the bottom;

(10) FIG. 9 is a schematic depiction in a transverse section of the bottom of the second embodiment illustrating the distribution of the plastics material by virtue of the shape of the bottom;

(11) FIG. 10 is a view from below of the bottom according to a third embodiment;

(12) FIG. 11 is a view in section on a transverse plane of the bottom of the third embodiment;

(13) FIG. 12 is a view in section on a longitudinal plane of the bottom of the third embodiment.

DETAILED DESCRIPTION

(14) With reference to FIGS. 2 to 12, a container 1 according to the invention is shown.

(15) The following description of the features of the container 1 according to the invention also applies to the features of a mold for manufacturing this container 1, it being understood that the mold has an impression intended to give the container its final shape and having a complementary shape.

(16) The mold is a mold for manufacturing by blow-molding or stretch-blow-molding a blank made of plastics material. To this end, the mold according to the invention comprises a mold bottom which has an upper surface complementary to the impression of a bottom of the container 1 as described below.

(17) The container 1 according to the invention is a container made of plastics material. More specifically, it is a container made of polyethylene terephthalate.

(18) This container 1 is provided with a body 11 and with a bottom 12 in the continuation of the body 11 at a lower end of the body 11.

(19) The container 1 according to the invention is what is known as a flat container.

(20) As is illustrated in FIGS. 2, 4, 5 and 10, the bottom 12 has an oblong curved contour in a view from below.

(21) In other words, the container 1 has smaller dimensions in its width than in its length. The bottom 12 thus comprises two long sides and two short sides.

(22) According to the present embodiments illustrated in FIGS. 2 to 12, the bottom 12 comprises: a seating surface 21; an arch 22 extending from the seating surface 21 as far as a central zone 23 of the bottom 12.

(23) The container 1 has a central axis C. The body 11 of the container extends along the central axis C from the bottom 12.

(24) The central zone 23 of the bottom 12 is more specifically centered on the central axis C.

(25) The arch 22 delimits a concavity from the outside of the container 1.

(26) Moreover, according to the present embodiments in FIGS. 2 to 12, the bottom 1 comprises, between the mutually facing bulges 3, and centered on the central zone 23 of the bottom 12, a dome 5, the profile of which, parallel to the standing plane, is an elongate oblong shape along the axis ML and which creates, from the outside of the container 1, a concavity in the arch 12, each curved portion 220 extending as far as the dome 5.

(27) The seating surface 21 for its part forms a standing plane 210 of the container 1 as is illustrated in FIG. 3.

(28) This standing plane 210 has an oblong curved shape. The shape adopted by the standing plane 210 may also be referred to as oval.

(29) Advantageously, the shape of the standing plane 210 is closed, as is the case in the embodiments illustrated in FIGS. 2 to 9. In other words, the standing plane of the container 1 that is exhibited by the seating surface 21 is continuous, meaning that, around the entire perimeter of the bottom 12, when the container 1 is stood on a support, the entire seating surface is in contact with the support.

(30) With reference to FIGS. 4 to 7, and 10 to 12, the standing plane 210 formed by the seating surface 21 extends along a longitudinal median axis ML and a transverse median axis MT.

(31) The longitudinal median axis ML and the transverse median axis MT cross one another along the central axis C of the container 1.

(32) According to the embodiment illustrated in FIGS. 10 to 12, the standing plane (210) is not closed. Specifically, the seating surface (21) has two narrowed portions (17) situated at the ends of the seating surface along the longitudinal median axis (ML).

(33) The seating surface 21 has a length T, with a value t, between its distal ends along the longitudinal median axis ML, that is to say with the longitudinal median axis ML meeting an exterior contour 211 of the seating surface 21.

(34) The seating portion 21 also has a width W, with a value w, between the distal ends along the transverse median axis MT, that is to say with the transverse median axis MT meeting the exterior contour 211 of the seating surface 21.

(35) More generally, the bottom 12, in a view from below as illustrated in FIGS. 4 and 5, extends along the longitudinal median axis ML and along the transverse median axis MT.

(36) This bottom 12 has a greater dimension along the longitudinal median axis ML than along the transverse median axis MT, thereby giving the standing plane an oblong curved shape.

(37) For each of the present embodiments in FIGS. 2 to 12, the bottom 12 of the container 1 according to the invention exhibits planar symmetry on a first plane in which the transverse median axis MT and the central axis C of the container 1 are inscribed, and planar symmetry on a second plane in which the longitudinal median axis ML and the central axis C of the container 1 are inscribed.

(38) According to the principle of the invention and with reference to FIGS. 2, 4, 5, 7, 10 and 11, the seating surface 21 has width reductions that are each situated on one side of the longitudinal median axis ML. Each width reduction extends longitudinally at least with respect to the central zone 23 along the transverse median axis MT, in each case on one side of the longitudinal median axis ML. In other words, these width reductions extend along the two long sides of the bottom 12, following the longitudinal median axis ML, on either side of the transverse median axis MT, and at least over a distance corresponding to an orthogonal projection of the central zone 23 onto the longitudinal median axis ML.

(39) Moreover, the arch 22 has, for each width reduction of the seating surface 21: an indentation 4 filling said width reduction of the seating surface 21; a curved portion 220 extending directly from the indentation 4 in the direction of the central zone 23.

(40) The indentations 4 each delimit, in a transverse section, a cavity from the outside of the container 1.

(41) As illustrated more specifically in FIGS. 7 and 11, each curved portion 220 extends directly from said indentation 4 in the direction of the central zone 23, and has, in a section plane passing through the central axis C and the transverse axis MT, a section in the form of a circular arc inscribed in a circle Cc, the center of which is situated at a distance DC, with a value dc, from the central axis C, measured along the transverse median axis MT.

(42) Each circle Cc has a radius Rc which may be for example equal to around 5.6 mm.

(43) These curved portions 220 are inscribed, still according to the views in FIGS. 7 and 11, in trapezoids, the short bases of which are oriented toward the central zone and the long bases of which are oriented toward the indentations 4.

(44) The curved portions 220 correspond to parts of the bottom 12 having an accentuated curvature from the indentation and in the direction of the central part 23 compared with conventional arches according to the prior art.

(45) As illustrated by the two embodiments shown in FIGS. 2, 4, 5 and 7, the arch 22 has two bulges 3, each bulge 3 integrating, as explained in detail below, a curved portion 220.

(46) With reference only to the second embodiment illustrated in FIG. 5, the arch 22 also comprises four branches that frame each bulge 3 in pairs.

(47) According to FIGS. 4 and 5, the bulges 3 are situated between the width reduction of the seating surface 21 and the central zone 23.

(48) In other words, the bulges 3 frame the central zone 23 along the transverse median axis MT, and thus frame the dome 5.

(49) With reference to FIGS. 2 and 7, the bulges 3 form, from the outside of the container 1, a concavity in the arch 22. The bulges 3 thus have a relief shape extending inside the volume of the container 1.

(50) With reference to FIGS. 2, 4, 5 and 7, each bulge 3 has: a front face 31 which is proximal to the central zone 23; a flat 32 extending from the front face 31 in the direction of the seating surface 21; a rear face 34 extending from the flat 32, curving in the direction of the seating surface 21, the rear face 34 being distal from the central zone 23.

(51) The rear face 34 of each bulge 3 meets one of the curved portions 220.

(52) With reference to FIGS. 4 and 5, in a view from below, the bottom 12 has: a distance D, with a value d, along the transverse median axis MT between a middle of the flat 32 of each bulge 3 and the central axis C; a distance L, with a value l, between the central axis C and each distal end of the seating surface 21 along the transverse median axis MT.

(53) In addition, the flat 32 has a length P, with a value p, along the longitudinal median axis ML.

(54) The bulge 3, at the front face 31, has a height H, with a value h.

(55) Each bulge 3, according to the embodiments in FIGS. 2 to 9, also has an offset 33 positioned between its flat 32 and its rear face 34. In this case, the rear face 34 extends more specifically from the offset 33.

(56) In a transverse section of each bulge 3 that is illustrated in FIG. 7, the front face 31, the flat 32 and the offset 33 together take on a crenelated shape.

(57) In other words, the front face 31 protrudes from the arch 22 in the direction of the flat 32, and the offset 33 extends down from the flat 32 in the direction of the arch 22.

(58) At the offset 33, the bulge 3 has a height G, with a value g.

(59) Still with reference to FIG. 7, for each bulge 3 and in a transverse section of the bottom 12, on the median plane, the rear face 34 has: an initial portion 341 adjacent to the flat; a terminal portion 342 adjacent to the seating surface 21.

(60) The initial portion 341 extends parallel to the arch 22, and more specifically at a projection underlying the arch 22.

(61) A tangent at the terminal portion 342 for its part forms, at its intersection with the seating surface 21, an angle ?, with a value a, with a straight line perpendicular to the transverse median axis MT and inscribed in a median plane of the bottom 12 in a transverse section of the bottom 12.

(62) According to the present embodiments, each curved portion 220 has a granular texture.

(63) These curved portions 220 may nonetheless have a smooth texture.

(64) As mentioned above, the arch 22 has indentations 4.

(65) These indentations 4 delimit, in a transverse section illustrated in FIG. 7, a cavity from the outside of the container 1.

(66) The indentations 4 have a length E, with a value e, along the longitudinal median axis ML.

(67) With reference to FIG. 7, and along the transverse median axis MT, each width reduction of the seating surface 21 has a width U, with a value u, and the seating surface 21 has a residual width O, with a value o.

(68) According to the second embodiment illustrated in FIG. 5, and as was mentioned above, the arch 22 comprises branches 6.

(69) Each branch 6 extends along an extension axis EX from the dome 5 as far as the seating surface 21, forming a flattened protuberance protruding into the concavity created by the arch 22 from the outside of the container 1.

(70) According to the present embodiments, each branch 6 also has a central notch 61 creating a concavity in the arch 22 from the outside of the container.

(71) With reference to FIG. 5, for two branches 6 on opposite sides from one another with respect to the longitudinal median axis ML, and in a view of the bottom 12 from below, the extension axes EX of these two branches 6 cross one another along the longitudinal median axis ML at a point R. The two points R resulting from these respective crossings of the branches 6 are then spaced apart from one another by a distance Z, with a value z.

(72) Moreover, still in a view of the bottom 12 from below, each extension axis EX crosses the longitudinal median axis ML, forming an angle ? (BETA), with a value b.

(73) As mentioned above, the arch 22 comprises a dome 5.

(74) This dome 5 has a profile, parallel to the standing plane, which is an elongate oblong shape along the axis ML.

(75) As illustrated in FIGS. 2 to 7, the dome 5 creates, from the outside of the container 1, a concavity in the arch 12.

(76) The dome 5 has: a length X, with a value x, along the longitudinal median axis ML; a width Y, with a value y, along the transverse median axis MT.

(77) With reference to the embodiment illustrated in FIGS. 10 to 12, the bottom 12 does not comprise bulges 3 or branches 6.

(78) According to this embodiment, the curved portions 220 extend directly from the indentations 4 as far as the dome 5. Consequently, in the view illustrated in FIG. 11, each individual section in the form of a circular arc of the curved portion 220 extends from an indentation 4 as far as the dome 5.

(79) With reference to FIG. 11, and in a median transverse section of the bottom 12 passing through the central axis C, each curved portion 220 has: an initial portion 221 adjacent to the dome 5; a terminal portion 222 adjacent to the seating surface 21.

(80) At its junction with the dome 5, the initial portion 221 extends parallel to the transverse median axis MT.

(81) A tangent to the terminal portion 222 forms, for its part, at the intersection of said terminal portion 222 with the seating surface 21 and in a similar manner to the rear face 34 of the first and the second embodiments, an angle ?, with a value a, with a straight line perpendicular to the transverse median axis MT and inscribed in a median plane of the bottom 12 in a transverse section of the bottom 12.

(82) The construction rules below are determined with respect to the features of the bottom 12 according to the two embodiments according to the invention that are illustrated in FIGS. 2 to 9: 10% w?dc?30% w, preferably with dc=20% w; 40% l?d?65% l, preferably with d=50% l; 30% w?y?40% w; 2.5 y?x?3.5 y, preferably with x=3 y; 30% t?x?70% t, preferably with x=54% t; 0.7 mm?h?2.3 mm, and preferably with h=1.5 mm; g<h, and preferably with g=33% h; 12.5??a?22.5?, preferably with a=17.5?; 65% t?e?75% t, preferably with e=70% t; 10% (o+u)?u?o, preferably with u=o.

(83) With respect to the first embodiment illustrated in FIG. 4, in which the bottom 12 does not comprise a branch 6, the following more specific rule applies: 40% t?p?65% t, preferably with p=55% t.

(84) With respect to the second embodiment illustrated in FIG. 5, the following more specific rules apply to the bottom 12: 20% t?p?40% t, preferably with p=25% t; 0.12?z/t?0.35, and preferably with z/t=0.27; 50??b?63?, preferably with b=57?.

(85) The construction rules below are determined with respect to the features of the bottom 12 according to the third embodiment according to the invention illustrated in FIGS. 10 to 12: 10% w?dc?30% w, preferably with dc=20% w; 2 y?x?3.5 y, preferably with x=2.4 y; 25% t?x?70% t, preferably with x=38% t; 12.5??a?35?, preferably with a=26?; 30% w?y?45% w.

(86) The above rules make it possible to obtain a bottom 12 having a continuous seating surface for a flat container 1, that is to say one which comprises a bottom 12 with an oval contour, starting from a blank made of plastics material and by virtue of a blow-molding or stretch-blow-molding manufacturing process, without boxing of the blank.

(87) As illustrated in FIG. 9, the bottom 12 of the container 1 according to the invention has, by virtue of these features, a specific distribution of the plastics material following the blow-molding of the blank in its transverse distribution. This specific distribution makes it possible to have a similar quantity of plastics material at the seating surface around the entire perimeter of the seating surface. Specifically, the bottom 12 does not have an accumulation of plastics material at the seating surface at the short sides of the container 1.

(88) Thus, the quantity of plastics material located transversely in the seating surface does not constitute an overthickness likely to cause imbalances or a structural instability of the container with respect to the quantity of material located at the longitudinal ends of the seating surface.