EP2735517B1 - Plastic container with reinforced base - Google Patents

Description

The present invention relates to a plastic container and more particularly to a plastic bottle. Such plastic containers have long been known from the prior art. In the design of such plastic containers and in particular their floors, various criteria must be considered. Thus, on the one hand an appealing design of these floors should be created, on the other hand, they should also have good stability and in some embodiments also have sufficient resistance to the pressure of the liquid in the container and also generally to pressures in a longitudinal direction of these containers be exercised.

In addition, one is always anxious to reduce the weight of such plastic containers as well as the weights of the corresponding floor sections. Therefore, container bottoms have been known for some time from the prior art, which in particular have radially extending reinforcing ribs.

The WO 2011/157952 A1 describes a plastic container according to the preamble of claim 1. This extends between a neck region and a bottom that can withstand a hydrostatic pressure.

The present invention has for its object to provide a plastic container available, which on the one hand has a high stability, but with a comparatively low soil weight manages. In this case, a sufficient stability of the soil, advantageously even at a non-centric load, for example, be ensured within a secondary packaging. In addition, such a container should also meet the criteria of portability and stability within a filling line become. In addition, the susceptibility to deformations should be reduced, ie it should be advantageously achieved that the container remains stable even with small deformations. Finally, it would still be desirable to provide a container which can also be manufactured during its manufacture with a reduced blow-molding pressure compared with the prior art.

These objects are achieved according to the invention by the subject matters of the independent patent claims. However, it should be noted that not every task is necessarily achieved by the subject matter of each individual claim.

Further advantages and embodiments will become apparent from the dependent claims.

A plastic container according to the invention has an opening region and a main body adjoining this mouth region in a longitudinal direction of the plastic container, which in turn has a peripheral wall running around in a circumferential direction of the container. Furthermore, the plastic container has a container base adjoining this basic body, this container bottom having a central region and a multiplicity of ribs which extend from this central region in the direction of the circumferential wall.

According to the invention, a step-shaped section extending at least partially in the circumferential direction of the container is provided in a peripheral region of the container bottom extending in a circumferential direction about the longitudinal direction of the container, wherein a height position of this step-shaped section varies in the longitudinal direction of the container.

It is therefore initially proposed that a step-shaped section is formed in the peripheral region of the container base, by means of which the stability of the container is fundamentally increased. Furthermore, however, this step-shaped portion does not extend in the circumferential direction at a constant height, but its height varies in the circumferential direction. In other words, the step-shaped portion along its course in the circumferential direction of the container at different heights. Thus, the step-shaped portion may have areas which are closer to the container bottom than other areas.

The bottom portion of the container thus has, in addition to the actual bottom surface, which at least in a standing container also facing down, still a peripheral surface. In addition, the bottom section also has a preferably likewise annular transition section, with which the bottom surface merges into the peripheral region. Advantageously, said peripheral region extends at least also in a longitudinal direction of the plastic container and preferably has an angle with respect to this longitudinal direction which lies between 0 ° and 40 °, preferably between 0 ° and 30 °, and preferably between 0 ° and 20 °.

Advantageously, said stepped portion extends fully circumferentially in the circumferential direction of the container, and thus more preferably forms a closed line.

Advantageously, said (reinforcing) ribs extend at least partially in the radial direction and preferably the (reinforcing) ribs each extend at least in sections in a radial direction of the container, i. a direction which would intersect a geometric axis of rotation or the longitudinal direction of the container. In the present disclosure, both the term rib and groove are used. Both terms designate the same objects. However, the term rib describes the technical function and the notion of the groove the geometric design. In other words, the reinforcing ribs are formed as a groove-shaped structure.

Advantageously, the reinforcing ribs or grooves extend in a predefined direction, and this direction preferably has a straight course, at least when projected in a specific projection direction. In particular, these reinforcing ribs have a substantially rectilinear profile when projected in the longitudinal direction of the container. Advantageously, the reinforcing ribs extend along their entire course in a direction which is composed of components of a radial direction of the container and the longitudinal direction.

Advantageously, these ribs are formed as reinforcing ribs and have, for example, in the interior of the container extending buckles. Through these reinforcing ribs, the rigidity of the soil can be increased in its entirety.

In a further advantageous embodiment, the central area is at least partially dome-shaped. For example, a dome-shaped section can be provided within the central area. Advantageously, this dome-like section can extend in the direction of the interior of the container.

In a further advantageous embodiment, the container or the bottom has at least two, preferably at least three different types of reinforcing ribs. Advantageously, these ribs differ in terms of their length. Thus, for example, a first number of main ribs may be provided, which are formed longer and further a second plurality of side ribs, which are preferably shorter than the main ribs. It is possible that the main and the sub-ribs are each arranged alternately in the circumferential direction.

In a further advantageous embodiment, the stepped portion is formed such that a circumference of the container or a cross section of the container in the region of the step portion from top to bottom, i. towards the floor, rejuvenated.

Advantageously, the step-shaped section has, at least in sections, a curved course relative to the longitudinal direction of the plastic container (or in a projection perpendicular to the longitudinal direction). This means that the course, if it is traced in the circumferential direction of the container, is in each case curved at least in sections. Thus, the height of this step-shaped portion preferably does not change stepwise, but continuously.

Furthermore, the step-shaped course with respect to the longitudinal direction of the plastic container on a wave-shaped or sinusoidal course. This design of the bottom with the curved stepped portion and the design of the reinforcing ribs, the new floor has improved stability against pressure from above the container and against a force from below, for example by the closure of a bottle (for example, when stacking). More precisely, the force is optimally distributed by this curved step, or the curved stepped portion and also the stiffening ribs ending at the various positions. The foothills The reinforcing ribs do not form horizontally conceived stress peaks or possible kinks.

Due to the different groove course of short and longer reinforcing ribs, a tension of the side wall is generated, so that, in combination with the curved, step-shaped section, an improved longitudinal force distribution is achieved and thus the bottom is more stable than in the container of the prior art. This can be achieved in particular for low container weights. In this case, this step-shaped section advantageously has a surface extending in the radial direction and in the circumferential direction (and thus in particular annular), which points downwards.

This curved, step-shaped section can also have a different number of wave high and low points depending on the number of grooves or the number of reinforcing ribs. However, at least two wave peaks and two wave depths are advantageously distributed around the container circumference. Advantageously, these high and low points alternate between the foothills of the reinforcing ribs in the respective flank surfaces of the containers. The peak-to-valley value of the curved, step-shaped section is between 2% and 40% of a height of the floor, preferably between 5% and 30% and particularly preferably between 10% and 25%.

The height of the floor is determined in particular by the height of a corresponding bottom part, which forms its bottom area during a blowing process of the plastic container.

The step-shaped portion advantageously has a difference in diameter (between the major diameter and the flank surfaces) which is dependent on the major diameter. The stepped portion connects the bottle body or the body with the ground. The difference in diameter is preferably between 0.5 mm and 2 mm, more preferably between 0.6 mm and 1.5 mm and particularly preferably between 0.75 mm and 1.25 mm.

Also, the mentioned dom-shaped portion in the central region can assume different radii of curvature at different major diameters of the container. In another area of the bottom section, in particular around the Injection point extends, is advantageously provided a concave dome in the interior of the container dome. Thus, for example, a main dome may be provided, which extends from a peripheral edge of the container in the central region, and within the central region, a second dome may be provided, in particular with a greater curvature. Also, a radius of this "small dome", which is provided in the region of the center of the floor, may have a radius which is selected in dependence on a major diameter and a ground level.

In a further advantageous embodiment, at least one rib extends in the above-mentioned peripheral region of the container bottom. Advantageously, at least one rib extends in the longitudinal direction of the container or at an angle relative to the longitudinal direction of the container, which is smaller than 40 °, preferably smaller than 30 °, preferably smaller than 20 ° and preferably smaller than 10 °.

However, at least one rib is preferred, and more preferably all the ribs are spaced from the step-shaped portion. Thus, the respective reinforcing ribs preferably end in front of the step-shaped section. Particularly preferably, the respective reinforcing ribs always end directly below the stepped portion, so that although the reinforcing ribs are always formed up to the step-shaped portion, but never pass through this.

In a further preferred embodiment, at least two reinforcing ribs end at different heights of the container with respect to their longitudinal direction. Preferably, the reinforcing ribs of a first group of reinforcing ribs end at a first height of the container and the reinforcing ribs of a second group of reinforcing ribs terminate at a second, deviating, height. However, it would also be conceivable that the ribs end at the same height.

The plastic container is preferably a blow-molded container and in particular a stretch blow-molded plastic container. Preferably, this plastic container is made of PET.

In a further advantageous embodiment, at least one reinforcing rib cuts or touches the central region or protrudes into it. In a further advantageous embodiment, the transition region of the bottom section has a in the circumferential direction of the container extending wall portion which is curved in the longitudinal direction. Particularly preferably, in addition to this first wall area extending in the circumferential direction, a second wall area extending in the circumferential direction is provided, which is also preferably curved. In this embodiment, therefore, the flank of the base, in particular below the step-shaped portion, at least two surfaces, which are particularly preferably rounded and more preferably not tangential.

In a further advantageous embodiment, the plastic container has an annular base. Advantageously, this annular standing surface is formed in the bottom region and is particularly preferably interrupted only by the reinforcing ribs or a part of these reinforcing ribs.

In a further embodiment, the bottom section thus has a standing surface, wherein preferably a stator diameter is selected as a function of a main diameter of the container. Advantageously, this stator diameter is between 65 and 85% of the main diameter of the container and preferably between 70% and 80% of this major diameter.

Advantageously, at least two reinforcing ribs, which may already end before the step-shaped section, have a different groove cross-sectional geometry with respect to each other. In particular, the groove radii of these two groove cross sections may differ from one another. These groove radii are advantageously between 0.5 mm and 2 mm, more preferably between 0.6 mm and 1.5 mm and particularly preferably between 0.75 mm and 1.25 mm.

In a further advantageous embodiment, the height of a groove outlet, in particular in the flank surfaces, of stiffening groove to stiffening groove may be different.

As mentioned, longer ribs or main ribs may intersect the above-mentioned dome-shaped section and extend to this dome-shaped section into the central region of the bottom.

The present invention is further directed to a container bottom for a plastic container. This container bottom has in this case a central region, in which in particular an injection point is arranged. In addition, the container bottom also has a plurality of - in particular groove-like - reinforcing ribs which extend in a radial direction of the container bottom. According to the invention, a step-shaped section extending at least partially in the circumferential direction of the container is provided in a peripheral region of the container bottom extending in a circumferential direction about the longitudinal direction of the container, wherein a height position of this step-shaped section varies in the longitudinal direction of the container.

It is therefore also with regard to the container bottom, which may be combined in particular with any containers, suggested that the said stepped portion does not extend at a constant height (relative to a direction perpendicular to the ground direction, which corresponds to a longitudinal direction of the container) , Preferably, the container bottom is designed in the manner described above. Preferably, the container bottom has a substantially circular cross-section. In principle, however, it would also be conceivable to use the step-shaped section according to the invention also in containers with other common cross sections (for example rectangular cross sections, square cross sections, cross sections with rounded corners, oval cross sections and the like).

The present invention is further directed to the use of a container of the type described above and / or a container bottom of the type described above for filling a still (i.e., in particular non-carbonated or low-carbon) beverage, and in particular a still water.

Further advantages and embodiments will become apparent from the accompanying drawings.

Fig. 1a - 1d

ein erfindungsgemäßes Behältnis in einer ersten Ausführungsform; und

Fig. 2a - 2e

ein erfindungsgemäßes Behältnis in einer zweiten Ausführungsform.

Show:

Fig. 1a - 1d

a container according to the invention in a first embodiment; and

Fig. 2a - 2e

a container according to the invention in a second embodiment.

The FIGS. 1a-1d show a container 1 according to the invention in a first embodiment. It shows Fig. 1 This container has a mouth region 2 with a thread on which a closure can be screwed. At this mouth region 2, a base body 4 of the container follows, which encloses substantially the inner volume of the container 1.

In turn, a bottom region or the container bottom 6 adjoins this base body 4, which is to be described here in the context of the invention. This container bottom 6 has a stepped portion 44 which, as in Fig. 1a recognizable forms a wave-shaped course with high points and low points. In this case, this container bottom reinforcing ribs 64 and 66, which are formed in different lengths.

It can be seen that these reinforcing ribs also extend into a peripheral region 60 of the container bottom 6, but do not touch or cut the step-shaped section 44. The reference numeral 42 denotes a peripheral wall of the main body, which encloses substantially the volume of liquid held or receivable by the plastic container.

Fig. 1b shows an oblique view of a container bottom 6. This case again has the two reinforcing ribs 64 and 66. The reference numeral 62 denotes a central region of the container base 6, in the middle of the injection point 68 is arranged. It can be seen that the longer reinforcing ribs 64 extend as far as this central region 62, but the shorter reinforcing ribs 66 terminate preferably in front of the central region 62, wherein it would also be conceivable for the reinforcing ribs 66 also to extend into the central region 62. The central area here has a circular cross-section. The radius of this central region is preferably between 1/7 and 6/7 of the radius of the bottom section, preferably between 1/6 and 5/6 of the radius of the bottom section, preferably between 1/5 and 4/5 of the radius of the bottom section, preferably between 1 / 5 and 3/5 of the radius of the bottom section.

Reference numeral 76 also indicates the bottom portion within which the reinforcing ribs 66 and 64 are at least partially formed. This bottom region 76 extends from the central region 62 up to the actual footprint 70.

Also, this bottom portion 76 is domed domed inward. However, a corresponding radius of curvature of the central region 62 is smaller than a bulge region of the bottom region 76. In this case, this bottom region 76 is thus formed annular in cross section. The reference character R66 indicates a radius of curvature of the shorter reinforcing ribs 66.

The reference numeral 72 denotes a stand ring, or an outer circle on which the container comes to a standstill. This circle is followed by a circular, curved surface 75 and then back in the direction of the main body of the container 2 flank surfaces 32 and 36, which are delimited from each other by a rounding 34 extending therebetween. These two flank surfaces are formed curved with respect to the longitudinal direction L of the container 1.

As mentioned above, the step-shaped section 44 has a wave-shaped structure and thus wave peaks 44a and wave depression points 44b. In this case, a wave peak is understood as meaning the region which is arranged closer to the bottom or the reinforcing ribs, and below a wave bottom point that section which is farther away from these reinforcing ribs 64, 66. The reference numeral 38 denotes a bottom flank, with which the container base 6 passes over the step-shaped section 44 into the base body 4.

Fig. 1c shows again a top view of the container bottom 6. Here one recognizes the end portions 66a of the short reinforcing ribs 66 and the end portions 64a of the longer reinforcing ribs, which each taper radially inwardly.

In this embodiment, the reinforcing ribs 64 and 66, each terminating in front of the stepped portion 44, may have a different groove cross-sectional geometry to each other. The groove radii of the two groove cross sections may also be different. However, a geometry of the individual reinforcing ribs preferably does not change in its course, but may change depending on the groove depth and the main diameter X (of the container bottom in its entirety).

In Fig. 1d one recognizes further that a groove contour of the respective shorter reinforcing ribs 66 and the basic contour of the container base 6 in the region of the flank surfaces Further, these small reinforcing ribs 66 intersect the bottom portion 76 and the large dome, respectively, in the illustrated range E-F at a predetermined angle a, that of the major diameter X and the ground height H6 depends. This angle a is preferably between 5 ° and 15 °, preferably between 8 ° and 12 °. In this case, this angle a also depends on the radius of curvature of the transition region R76. The reference character T66 in FIG Fig. 1d indicates a groove depth of the reinforcing rib 66.

The groove contour of the long reinforcing rib 64 does not follow the basic contour of the bottom shape in the area A-B. In the region BC, the groove contour follows the base contour parallel to the central region 62. The distance between the groove contour and the base contour can vary depending on the ground height and the main diameter X, as mentioned in more detail above, and is preferably between 0.75 mm and 1.5 mm , The groove depth can be different in the case of the longer and shorter reinforcing ribs or stiffening ribs 64, 66.

Preferably, the groove geometry of the individual reinforcing ribs, that is to say in particular the angle b66 and R 66, remains constant throughout the course. However, they may change depending on the groove depth and the major diameter of the container bottom 6. The groove opening angle b66 of the reinforcing ribs may have different values. This angle is preferably in a range between 55 ° and 120 ° and particularly preferably between 70 ° and 115 °.

The FIGS. 2a-2e show a further embodiment of a container according to the invention 1. This is again in Fig. 2a the container 1 shown in a side view, Fig. 2b shows a plan view of the container bottom 6, wherein the reinforcing ribs 64 and 66 can be seen and Fig. 2c again shows an oblique view of the container bottom 6. Some features of this container bottom 6 are consistent with the in Fig. 1b container bottom shown and are therefore not explained in detail.

Unlike the in Fig. 1b shown container bottom 6, however, the long reinforcing ribs 64 extend only to the edge of the central region 62. Also here have the reinforcing ribs 64 no consistent profile, but this changes. In addition, the in Fig. 2c bottom shown a variety of lateral stiffening ribs 69, which are arranged on the lateral edge of the container bottom 6. However, these lateral stiffening ribs 69 do not intersect the stepped portion 44 either.

The reinforcing ribs 64 and 66, which in turn terminate here in front of the step-shaped section, can here again have a different or different groove cross-sectional geometry. Again, reinforcing ribs can go beyond the rounding of the flank surface, but not cut the step-shaped section. The groove diameters of these reinforcing ribs may be different. The groove contours of these reinforcing ribs do not follow the basic contour of the soil in its entire course here. The reference R64 in FIG Fig. 2e indicates a radius of curvature of the reinforcing ribs 64.

Again, as shown here, the main reinforcing ribs 64 extend tangentially in the bottom surface, but may leak even before the large dome-like structure 76. Preferably, they have a radius that is constant in a range J-K and is preferably between 0.2 and 1.5 mm. The intermediate ribs 66 also preferably run tangentially in the bottom surface here and end within the bottom surface, as shown. Advantageously, these side reinforcing ribs or side ribs end in a ratio with respect to the major diameter X in a range which is between 25% and 75% and preferably between 30 and 70% and particularly preferably between 40 and 60%. By this choice of the respective lengths, a particularly favorable stiffening of the container bottom 6 can be achieved.

Significant improvements over the prior art have been made with the new floor design shown in the figures. In particular, it has been achieved that the container bottom 6 is still very stable even with minimal weight.

The Applicant reserves the right to claim all features disclosed in the application documents as essential to the invention, provided they are novel individually or in combination with respect to the prior art.

LIST OF REFERENCE NUMBERS

1

container

2

mouth area

4

body

6

container base

32/36

flank surfaces

34

rounding

38

bottom edge

42

peripheral

44

stepped section

44a

Wave high points

44b

Shaft lowlights

60

Peripheral area of the bottom of the container

62

Central area of the container floor

64

long reinforcement ribs

66

short reinforcing ribs

66a

End region of the reinforcing ribs 66

68

injection point

69

lateral reinforcement rib

70

footprint

72

outer circle

75

circular, curved surface

76

floor area

E-F

shown area

A

angle

X

Hauptdurmesser

H6

ground level

B-C

Area

R64, R66

radius of curvature

b66

Groove opening angle

T66

groove depth

Claims (10)

1. Plastics material container (1) with a mouth region (2), a main body (4) adjoining this mouth region (2) in a longitudinal direction (L) of the plastics material container (1), this main body having a peripheral wall extending in a circumferential direction of the plastic container (1) and a container base (6) adjoining this main body (4), wherein this container base has a central region (62) and a plurality of reinforcing ribs (64, 66) which, starting from this central region (62), extend in the direction of the circumferential wall (42), wherein a stepped portion (44) extending at least partially in the circumferential region of the plastic container (1) is provided in a circumferential region (60) of the container base (6) which extends around the longitudinal direction (L), characterized in that a vertical position of this stepped portion (44) varies in the longitudinal direction (L).
2. Plastics material container (1) as claimed in Claim 1, characterised in that the stepped portion (44) has at least in portions a curved configuration relative to the longitudinal direction (L) of the plastics material container (1).
3. Plastics material container (1) as claimed in Claim 2, characterised in that the stepped portion (44) has an undulating configuration relative to the longitudinal direction (L) of the plastics material container (1).
4. Plastics material container as claimed in at least one of the preceding claims, characterised in that at least one reinforcing rib (64) extends in the circumferential region (60) of the container base (6).
5. Plastics material container (1) as claimed in at least one of the preceding claims, characterised in that each reinforcing rib (64, 66) is spaced from the stepped portion (44).
6. Plastics material container (1) as claimed in at least one of the preceding claims, characterised in that at least two reinforcing ribs (64, 66) end at different heights of the container (1) relative to the longitudinal direction (L) thereof.
7. Plastics material container (1) as claimed in at least one of the preceding claims, characterised in that at least one reinforcing rib intersects the central region (62).
8. Plastics material container (1) as claimed in at least one of the preceding claims, characterised in that the central region (62) has a dome-like structure at least in portions.
9. Plastics material container (1) as claimed in at least one of the preceding claims, characterised in that the circumferential region (60) has a first wall region which extends in the circumferential direction and is curved in the longitudinal direction (L).
10. Plastics material container (1) as claimed in at least one of the preceding claims, characterised in that the plastics material container (1) has an annular support surface.

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