Flattened container comprising an arched bottom with square seat

Abstract

Container of plastic material having a flattened body and a bottom in the extension of the body having peripheral seat defining a seating plane the contour of which has in the same plane a large dimension A1 and a small dimension A2 that is strictly smaller than the large dimension, and an inner annular cheek substantially perpendicular to the seating plane. The bottom having a concave arch that extends from the seat towards a central zone. A height H of the cheek and a width L of the seating plane are such that $0.5\frac{L}{H}2.5.$
A transverse extension A of the seating plane and a transverse extension B of the body, measured near the bottom, are such that $\frac{A}{B}0.85.$

Claims

1. A container of plastic material, having a flattened body and a bottom in an extension of the body at a lower end thereof, the bottom comprising: a peripheral seat defining: a seating plane the contour of which has in the same plane a large dimension A1 and a small dimension A2 that is smaller than the large dimension, and an inner annular cheek substantially perpendicular to the seating plane; a concave arch that extends from the seat, in an extension of the cheek, towards a central zone of the bottom defining a disc that extends axially, projecting towards an interior of the container; wherein: a height H of the cheek and a width L of the seating plane are such that: $0.5\frac{L}{H}2.5$ a transverse extension A of the seating plane and a corresponding transverse extension B of the body, measured near the bottom, are such that: $\frac{A}{B}0.85;$ and wherein the seating plane has a maximum width L1, measured parallel to the large dimension A1, and a minimum width L2, measured parallel to the small dimension A2, and the ratio L1/L2 is greater than 1.

2. The container according to claim 1, wherein the small dimension A2 of the seating plane and a corresponding small dimension B2 of the body near the bottom are such that: $\frac{A2}{B2}0.90.$

3. The container according to claim 2, wherein the small dimension A2 of the seating plane and the small dimension B2 of the body near the bottom are such that: $\frac{A2}{B2}0.95.$

4. The container according to claim 1, wherein the maximum width L1 and the minimum width L2 of the seating plane are such that: $1<\frac{L1}{L2}<3.$

5. The container according to claim 4, wherein the maximum width L1 and the minimum width L2 of the seating plane are such that: $\frac{L1}{L2}2.$

6. The container according to claim 1, wherein the cheek has, parallel to the large dimension, a minimum height H1, and parallel to the small dimension, a maximum height H2 such that: $\frac{H1}{H2}<1.$

7. The container according to claim 6, wherein the minimum height H1 and the maximum height H2 of the cheek are such that: $0.5<\frac{H1}{H2}<1.$

8. The container according to claim 7, wherein the minimum height H1 and the maximum height H2 of the cheek are such that: $\frac{H1}{H2}0.95.$

9. The container according to claim 1, wherein the large dimension A1 and the small dimension A2 of the seating plane are such that: $\frac{A1}{A2}>1.5.$

10. The container according to claim 9, wherein the large dimension A1 and the small dimension A2 of the seating plane (8) are such that: $\frac{A1}{A2}>1.8.$

11. The container according to claim 1, wherein at any point M on an outer perimeter of the seating plane, the width L.sub.M of the seating plane is such that: $\frac{1}{15}\frac{L_M}{C_M}\frac{1}{5}$ where C.sub.M is the distance from the point M to an axis of the container.

12. A container of plastic material, having a flattened body and a bottom in the extension of the body at a lower end thereof, the bottom comprising: a peripheral seat lying in a seating plane, the seat defined by a contour having in the seating plane and passing through a vertical axis of the container a transverse maximum length A1 and a transverse minimum length A2, and an inner annular cheek substantially perpendicular to the seating plane; and a concave arch that extends from the seat, in an extension of the cheek, towards a central zone of the bottom defining a disc; wherein a height H of the cheek and a width L of the seating plane at a location where the height of the cheek is measured are such that: $0.5\frac{L}{H}2.5$ a transverse extension A of the seating plane passing through the vertical axis of the container and a corresponding transverse extension B of the body passing through the vertical axis of the container, measured at or near the bottom are such that: $\frac{A}{B}0.85;$ and the seating plane has a maximum width L1, measured along the transverse maximum length A1 and a minimum width L2, measured along the transverse minimum length A2, and the ratio L1/L2 is greater than 1.

Description

(1) Other objects and advantages of the invention will be seen from the description of a preferred embodiment, provided with reference to the appended drawings in which:

(2) FIG. 1 is a view in perspective from below of a container of plastic material, with an inset in larger scale detailing the bottom of the container;

(3) FIG. 2 is a bottom view of the bottom of the container of FIG. 1;

(4) FIG. 3 is a detailed view in cross-section of the container of FIG. 2, along cutting plane III-III;

(5) FIG. 4 is a detailed view in cross-section of the container of FIG. 3, along the cutting plane IV-IV;

(6) FIG. 5 is a view similar to FIG. 4, according to a variant of embodiment.

(7) Represented in FIG. 1 is a container 1 formed by stretch blow-molding, in a mold with the impression of the container 1, from a preform in plastic material such as PET (polyethylene terephthalate).

(8) The container 1 comprises a body 2 which extends along a principal axis X and is extended, at a lower side, by a bottom 3, and an upper side, opposite to the bottom 3, by a shoulder 4 which in turn is extended by a neck 5 defining a mouth.

(9) The body 2 has a cross-section that is flattened in shape, in this instance substantially oval. This shape extends to the bottom 3, the contour of which is substantially the same as the body 2 in cross-section.

(10) At the junction between the body 2, at the lower end thereof, and the bottom 3, the container 1 has an outer connecting fillet 6 having an arc-of-circle profile of small radius (equal to or less than 2 mm).

(11) The bottom 3 comprises a peripheral seat 7 which defines a continuous seating plane 8, substantially perpendicular to the principal axis X of the container 1, and by which said container can rest flat on a flat surface (particularly the upper surface of the table or a conveyor belt, in a handling machine on a container production line).

(12) The seating plane 8 is transversely delimited towards the exterior (i.e. opposite the axis X of the container) by an outer perimeter 9 defined internally by the fillet 6.

(13) A transverse extension of the seating plane 8 is denoted A, measured perpendicularly to the principal axis X of the container 1 at the outer perimeter 9. Because the seating plane 8 has an oval contour, A is not constant and has a maximum, called large dimension and denoted A1, and a minimum, called small dimension and denoted A2, the ratio of which must be greater than 1:

(14) $\frac{A1}{A2}>1$

(15) More specific examples of this ratio will be provided hereinafter.

(16) Furthermore, B denotes a transverse extension (or width) of the body 2 measured perpendicularly to the principal axis X of the container, near the bottom 3, i.e. at a distance from the seating plane 8 that is less than or equal to of the total height of the body 2. Since the body 2 in cross-section has an overall contour like the bottom 3, B is not constant and has a maximum B1, called large dimension of the body and a minimum B2, called small dimension of the body, the ratio of which must be greater than 1:

(17) $\frac{B1}{B2}>1$

(18) The seat 7 comprises an inner annular cheek 10 which extends axially towards the interior of the container 1 in the extension of the seating plane 8, substantially perpendicular with respect thereto. The seating plane 8 is connected to the cheek 10 by an inner fillet 11 having an arc-of-circle profile of small radius (equal to or less than approximately 2 mm), or a medium radius (of between approximately 2 mm and 5 mm).

(19) The seating plane 8 is transversely delimited towards the interior (i.e. in the direction of the axis X of the container) by an inner perimeter 12 defined externally by the inner fillet 11.

(20) The bottom 3 further comprises a concave arch 13, with the concavity turned outward from the container 1. Said arch 13 extends from the seat 7, in the extension of the cheek 10, to a central zone of the bottom defining a disc 14 that extends axially, projecting towards the interior of the container 1.

(21) The following notation is used: H is the height of the cheek 10 (taken together with an internal height of the seat 7), measured axially between the seating plane 8 and the junction of the cheek 10 with the arch 13; L is a width of the seating plane 8 (taken together with a width of the seat 7), measured radially between the inner perimeter 12 and the outer perimeter 9.

(22) The bottom 3 is dimensioned as follows: on the one hand, the height H of the cheek 10 and the width L of the seating plane 8 are such that:

(23) $0.5\frac{L}{H}2.5$ on the other hand, the transverse extension A of the bottom 3 and the transverse extension B of the body 2 near the bottom 3 are such that:

(24) $\frac{A}{B}0.85$

(25) This dimensioning significantly increases the stability of the container 1.

(26) The ratios A1/B1 and A2/B2 can be dimensioned separately; they can be substantially identical:

(27) 0$\frac{A1}{B1}\frac{A2}{B2}$

(28) According to a preferred embodiment, the ratio A2/B2 is equal to or greater than 0.90, and for example substantially equal to 0.95, as illustrated in FIG. 3:

(29) $\frac{A2}{B2}0.90$

(30) and for example:

(31) $\frac{A2}{B2}0.95$

(32) This dimensioning, which moves the outer perimeter 9 of the seating plan 8 outwards, that is, opposite to the axis X, gives the container 1 a substantially cylindrical shape near the bottom 3. The result is increased stability of the container 1 in the plane of the small dimension A2.

(33) The ratio A1/B1 can also be equal to or greater than 0.90, and for example substantially equal to 0.95, as illustrated in FIG. 4:

(34) $\frac{A1}{B1}0.90$

(35) and for example:

(36) $\frac{A1}{B1}0.95$

(37) As a variant, the ratios A1/B1 can be different, the ratio A1/B1 preferably being less than the ratio A2/B2:

(38) $\frac{A1}{B1}<\frac{A2}{B2}$

(39) Thus, the ratio A2/B2 being maintained equal to or greater than 0.90, and for example substantially equal to 0.95 as illustrated in FIG. 3, the ratio A1/B1 is then less than 0.90, and for example substantially equal to 0.89, as illustrated in FIG. 4:

(40) $\frac{A1}{B1}<0.90$

(41) and for example:

(42) $\frac{A1}{B1}0.89$

(43) This makes it possible to maintain the stability of the container 1 in the plane of the small dimension A2 (high A2/B2 ratio), while maintaining good blowability of the container (relatively low A1/B1 ratio) in the plane of the large dimension A1, where the stretching is more difficult but where the stability of the container 1 is naturally better.

(44) According to a preferred embodiment illustrated in FIGS. 2, 3 and 4, the width L of the seating plane 8 is not constant along its perimeter 9, but has a maximum denoted L1, measured parallel to the large dimension A1, and a minimum denoted L2, measured parallel to the small dimension A2, the ratio of which must be greater than 1:

(45) $\frac{L1}{L2}>1$

(46) In other words, the seating plane 8 is wider parallel to the large dimension A1 than parallel to the small dimension A2. This greater width relative to the seating plane 8 in the larger dimension contributes to good blowability of the bottom 3 in this direction, minimizing the risk of appearance of distortions (or flatness defects) on the seating plane 8.

(47) Moreover, the narrowness of the seating plane 8 in the small dimension gives said seating plane a quasi-linear character that decreases the risks of hyperstatism of the seat 7 and consequently increases the stability of the container 1.

(48) Preferably, the ratio L1/L2 is between 1 and 3:

(49) $1<\frac{L1}{L2}<3$

(50) According to an embodiment illustrated in FIG. 1, this ratio is equal to approximately 2:

(51) 0$\frac{L_1}{L_2}2$

(52) Moreover, according to a preferred embodiment illustrated in FIGS. 3 and 4, the height H of the cheek 10 is not constant along the perimeter 9 of the seating plane 8, but has a minimum, denoted H1, measured parallel to the large dimension A1 of the seating plane, and a maximum, denoted H2, measured parallel to the small dimension A2, the ratio of which must be less than 1:

(53) $\frac{H1}{H2}<1$

(54) preferably the ratio H1/H2 is between 0.5 and 1:

(55) $0.5<\frac{H1}{H2}<1$

(56) According to a particular embodiment illustrated in FIGS. 3 and 4, this ratio is approximately 0.95:

(57) $\frac{H1}{H2}0.95$

(58) Thus, the cheek 10 is higher in the plane of the small dimension A2 than in the plane of the large dimension A1. This characteristic contributes in particular: to a better blowability of the bottom 3 in the plane of the large dimension A1, while minimizing the quantity of material requiring an axial stretching; better rigidity of the arch 13, thanks to the variation of height of its outer perimeter (at its junction with the cheek 10); greater rigidity of the seat 7 parallel to the small dimension A2, to the benefit of its stability in this direction.

(59) Thus, without compromising the stability, it is foreseeable that the container 1 could be flattened beyond a ratio A1/A2 (or B1/B2) greater than 1.5, to the benefit of the ergonomics. Preferably, the ratio A1/A2 (or B1/B2) must be greater than 1.8:

(60) $\frac{A1}{A2}>1.8$

(61) Thus, according to a particular embodiment illustrated in particular in FIG. 2, the ratio A1/A2 is approximately 1.9:

(62) $\frac{A1}{A2}1.9$

(63) The variations, mentioned above, of the width L of the seating plane 8 and/or the height H of the cheek 10 can be expressed by a variation of the ratio L/H along the perimeter 9, with, preferably:

(64) $\frac{L2}{H2}<\frac{L1}{H1}$

(65) This inequality results in particular in the fact that: at a constant height H (H1=H2), the seating plane 8 is wider in the large dimension (L1>L2); at a constant width L1 of the seating plane 8 (L1=L2), the cheek 10 is higher in the small dimension (H2>H1).

(66) The width of the seating plane 8, denoted L.sub.M, can also be dimensioned at any point M of the outer perimeter 9 of the seating plane 8, as a function of the distance, denoted C.sub.M, from the point M to the axis X of the container 1, preferably with:

(67) $\frac{1}{15}\frac{L_M}{C_M}\frac{1}{5}$

(68) Thus, the width of the seating plane 8 at any point remains small with respect to the distance to the axis X of the container 1. This guarantees a more homogeneous formation of the seat 7 during the blow-molding of the container 1, the material being distributed more uniformly over the periphery of the seating plane 8. The result is a better blowability of the container 1, and better stability thereof.

(69) According to a preferred embodiment, the bottom 3 of the container 1 is formed by a stretch blow-molding method comprising a boxing operation, in a mold provided with a side wall defining an impression corresponding to the body 2 of the container 1, and a mold bottom that is movable with respect to the wall, in such a way as to cause an overstretching of the bottom 3, resulting in good rigidity and a good impression thereof.