Abstract
A blow mould for forming plastic preforms into plastic containers, having at least two blow to mould side parts and a base part, which form a cavity, within which plastic preforms can be formed into the plastic containers by being acted upon by a flowable medium, wherein an inner wall of the blow mould side parts and of the base part having a contour which produces a predetermined shape of the plastic containers to be produced, wherein a plurality of openings being provided in at least one section of the base part, which openings allow a gaseous medium to be discharged during an expansion process of the plastic container. A ratio between a surface area of the base part and a surface area of the openings is 3-350, preferably 4-200, and particularly preferably 3-100.
Claims
1. A blow mould for forming plastic preforms into plastic containers, having at least two blow mould side parts and a base part, which form a cavity, within which plastic preforms can be formed into the plastic containers by being acted upon by a flowable medium, wherein an inner wall of the blow mould side parts and of the base part which delimits the cavity has a contour which produces a predetermined shape of the plastic containers to be produced, wherein a plurality of openings being provided in at least one section of the base part, which openings allow a gaseous medium to be discharged during an expansion process of the plastic container, and wherein a ratio between a surface area of the base part and a surface area of the openings is 35-175, and the ratio depends on the size of the bottle and the shape of the openings.
2. The blow mould according to claim 1, wherein a diameter of the base part is between 50 mm and 200 mm, and the surface area of the openings is between 23 mm.sup.2 and 500 mm.sup.2.
3. The blow mould according to claim 1, wherein the surface area of the base part is between 3900 mm.sup.2 and 65000 mm.sup.2, and the surface area of the openings is between 23 mm.sup.2 and 500 mm.sup.2.
4. The blow mould according to claim 1, wherein the openings are a plurality of holes and/or slots arranged in the base part.
5. The blow mould according to claim 4, wherein at least one hole has a diameter which is between 0.5 mm and 4 mm.
6. The blow mould according to claim 4, wherein at least one slot has a width which is between 0.4 mm and 2 mm.
7. The blow mould according to claim 1, wherein the base part is designed to form standing feet of the plastic container, wherein each standing foot having a plurality of openings.
8. The blow mould according to claim 7, wherein each standing foot has 7-35 openings.
9. A base part for a blow mould for forming plastic preforms into plastic containers according to claim 1, wherein the base part has an inner wall with a contour which produces a predetermined bottom shape of the plastic containers to be produced, wherein in at least one section of the base part a plurality of openings is provided which allow a gaseous medium to be discharged during an expansion process of the plastic container, and wherein a ratio between a surface area of the base part and a surface area of the openings is 35-175.
10. The base part according to claim 9, wherein a diameter of the base part is between 50 mm and 200 mm and the surface area of the openings is between 23 mm.sup.2 and 500 mm.sup.2.
11. The base part according to claim 9, wherein the surface area of the base part is between 3900 mm.sup.2 and 65000 mm.sup.2, and the surface area of the openings is between 23 mm.sup.2 and 500 mm.sup.2.
12. The base part according to claim 9, wherein the openings are a plurality of holes and/or slots arranged in the base part.
13. The base part according to claim 12, wherein at least one hole has a diameter which is between 0.5 mm and 4 mm.
14. The base part according to claim 12, wherein at least one slot has a width which is between 0.4 mm and 2 mm.
15. The base part according to claim 9, wherein the base part is designed to form standing feet of the plastic container, wherein each standing foot having a plurality of openings.
16. The base part according to claim 15, wherein each standing foot has 7-35 openings.
17. The base part according to claim 1, wherein a plurality of holes are arranged along a row.
18. The base part according to claim 1, wherein a combination of holes and slots is arranged in the base part, wherein the holes are preferably formed at the ends of the slots.
19. The base part according to claim 18, wherein a slot runs from hole to hole.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) Further advantages and embodiments can be seen in the attached drawings.
(2) In the drawings:
(3) FIG. 1 shows a roughly schematic representation of an apparatus for forming plastic preforms into plastic containers;
(4) FIG. 2 shows a representation of a blowing station with blow mould for forming plastic preforms into plastic containers;
(5) FIG. 3 shows a schematic representation of a base part according to the invention with vent holes;
(6) FIG. 4 shows a further schematic representation of a base part according to the invention with vent holes;
(7) FIG. 5 shows a further schematic representation of a base part according to the invention with vent holes;
(8) FIG. 6 shows a further schematic representation of a base part according to the invention with vent holes;
(9) FIG. 7 shows a schematic representation of a base part according to the invention with slots;
(10) FIG. 8 shows a further schematic representation of a base part according to the invention with slots;
(11) FIG. 9 shows a further schematic representation of a base part according to the invention with slots;
(12) FIG. 10 shows a schematic representation of a base part according to the invention with a combination of vent holes and slots;
(13) FIG. 11 shows a further schematic representation of a base part according to the invention with a combination of vent holes and slots;
(14) FIG. 12 shows a further schematic representation of a base part according to the invention with a combination of vent holes and slots;
(15) FIG. 13 shows a further schematic representation of a base part according to the invention with a combination of vent holes and slots;
(16) FIG. 14 shows a further schematic representation of a base part according to the invention;
(17) FIG. 15 shows a further schematic representation of a base part according to the invention;
(18) FIG. 16 shows an external view of the base part shown in FIG. 14;
(19) FIG. 17 shows a sectional view of the base part shown in FIG. 14;
(20) FIG. 18 shows a further schematic representation of a base part according to the invention;
(21) FIG. 19 shows an external view of the base part shown in FIG. 18;
(22) FIG. 20 shows a schematic representation of an arrangement of holes in series;
(23) FIG. 21 shows an exemplary hole pattern of a section of the base part;
(24) FIG. 22 shows a further exemplary hole pattern of a section of the base part; and
(25) FIG. 23-26 show further exemplary hole patterns of a section of the base part.
DETAILED DESCRIPTION OF THE INVENTION
(26) FIG. 1 shows a roughly schematic representation of an apparatus according to the invention for forming plastic preforms 10 into plastic containers 20. In this case, the plastic preforms 10 are fed via a feed device 55, such as a feed starwheel, and the finished containers are removed from the forming device 50 via a discharge device, such as a discharge starwheel 57. The forming device 50 has a rotatable carrier 54 on which a plurality of forming stations 52 are arranged. Each of these forming stations 52 has a blow mould 1.
(27) FIG. 2 shows a schematic view of a blow mould according to the invention. This blow mould has two side parts 2, 4 and a base part 6. Together, these two side parts and the base part 6 form a cavity 18 within which the plastic preforms are expanded to form the plastic containers. The vent openings described above are located in particular in the base part, but they can also be provided in the side parts, for example, in order to be able to better form complicated curvatures of the plastic container. The reference signs 12, 14 refer to support shells which support the side parts 2, 4 and the reference signs 22, 24 refer to blow mould supports to which the side parts are respectively attached (via the support shells 12, 14).
(28) The reference sign 60 refers to a vacuum generation device shown only schematically. This can be controlled in such a way that it extracts air from the interior of the blow mould for a predetermined period of time during the expansion of the plastic preforms.
(29) The following FIGS. 3 to 19 show different designs of base parts. For the sake of clarity, not all reference signs are repeated in the individual figures.
(30) FIG. 3 shows a schematic representation of a base part 6 according to the invention. In this embodiment, the base part has five sections 6a, 6b, 6c, 6d, 6e, which each form a standing area or are suitable and intended for forming a standing area of the plastic container 20.
(31) A plurality of openings 30, which in this case are holes, are formed in each standing area. In the embodiment example according to FIG. 3, ten holes 32 are arranged in each section 6a, 6b, 6c, 6d, 6e, all of which have the same diameter. In particular, FIG. 3 shows a base part 6 with a bottom diameter of 65 mm with ten holes in each section 6a, 6b, 6c, 6d, 6e, which have a diameter of 1 mm.
(32) FIG. 4 shows a further schematic representation of a base part 6 according to the invention. Here, too, openings 30 are provided in each section, which consist of a plurality of holes 32. In contrast to FIG. 3, here each section has twenty-four holes 32. This indicates that the diameter of the base part 6 of FIG. 4 is either larger than the diameter of the base part of FIG. 3 or the holes here have a smaller diameter than the holes in FIG. 3. In particular, FIG. 4 shows a base part 6 with a bottom diameter of 100 mm with 24 holes 32 in each section 6a, 6b, 6c, 6d, 6e, which have a diameter of 1 mm.
(33) FIG. 5 shows a further schematic representation of a base part 6 according to the invention. Here again, ten holes 32 are arranged in each section of the base part 6, but these are of a larger diameter than the holes in the base part of FIG. 3. In particular, FIG. 5 shows a base part 6 with a bottom diameter of 100 mm with ten holes 32 in each section 6a, 6b, 6c, 6d, 6e, which have a diameter of 1.5 mm.
(34) In the FIG. 6, nine holes 32 are arranged in each section of the base part 6, which have different diameters. In particular, FIG. 6 shows a base part 6 with a bottom diameter of 100 mm with nine holes 32 in each section 6a, 6b, 6c, 6d, 6e, wherein eight holes having a diameter of 1 mm and one hole having a diameter of 4 mm.
(35) FIGS. 7-9 show further schematic representations of a base part 6 according to the invention. In these embodiments, openings 30 are arranged in each section 6a, 6b, 6c, 6d, 6e of the base part 6, which are here designed as slots 33. In FIG. 9, a ring is additionally arranged on the base part 6 to improve stability. The ring can preferably be arranged on the outer circumference of the base part 6 by shrinking, screwing or welding.
(36) FIGS. 10-13 show a further embodiment of a base part 6 according to the invention, wherein the openings 30 here comprise a combination of holes 32 or bores and slots 33. It can be seen that holes 32 are arranged at the ends of the slots 33 in each case, wherein the slots 33 preferably extending from hole 32 to hole 32. In this embodiment, ten holes 32 and two slots 33 are thereby arranged in each section 6a, 6b, 6c, 6d and 6e of the base part 6.
(37) FIG. 14 shows another schematic representation of a base part 6 according to the invention. In this embodiment, a plurality of holes are arranged along a row 34, thus forming a kind of slot. In addition to these holes arranged in row 34, the base part may also have further holes 32. In particular, the arrangement of the openings 30 in FIG. 14 corresponds to the arrangement of the openings 30 in FIG. 10, except that the openings formed as slots in FIG. 10 are formed by a plurality of holes arranged along a row 34 in FIG. 14. The reference signs 6a-6e again indicate the individual sections of the base part 6.
(38) FIG. 15 shows a further schematic representation of a base part 6 according to the invention. FIG. 15 shows an embodiment in which two rows 34, each with a plurality of holes, are arranged parallel to each other. The arrangement of several such rows would also be conceivable.
(39) FIG. 16 is an external view of the base part 6 shown in FIG. 14. It can be seen that a channel 36 is formed on the outer surface 35 of the base part 6 in the area of each row 34. This channel allows the gaseous medium to be discharged from the base part more quickly. The channel 36 has a multiple width in relation to the diameter of the holes arranged in the row 34.
(40) FIG. 17 shows a sectional view of the base part 6 shown in FIG. 14. In this view, in particular, the plurality of holes arranged in a row 34 can again be seen, as well as the channels 36 arranged on the outer surface 35 of the base part 6, in the area of the rows 34.
(41) FIG. 18 shows a further schematic representation of a base part 6 according to the invention. In this embodiment, a plurality of holes is arranged along a spline 38. This arrangement of the openings 30 corresponds to the arrangement of the openings 30 in FIG. 11, with the difference that the openings formed as curved slots in FIG. 11 are formed by a plurality of holes arranged along a spline 38 in FIG. 18.
(42) FIG. 19 is an external view of the base part 6 shown in FIG. 18. On the outer surface 35 of the base part 6, the channel 36 can be seen here again, which corresponds in shape to the spline 38 formed by the holes.
(43) FIG. 20 shows a schematic representation of an arrangement of holes 32 in row 34. In the left-hand illustration, two rows 34 of holes 32 are visible, wherein the holes 32 are arranged at the same height and directly next to each other. In the right-hand illustration, two rows 34 of holes 32 are also visible, wherein the holes 32 are here arranged offset from each other. The small arrows indicate the distances between the holes, which can be the same or different.
(44) FIG. 21 shows an exemplary hole pattern 40 of a section of the base part. The hole pattern is perpendicular to a surface of the base geometry of the base and is preferably arranged centrally on the standing foot of the base part with respect to a centre point M of the base part. The individual holes 32 are arranged here in particular in several columns 44 and rows 42. The angles A and B depend on the width of the standing foot. The angle A, which extends from the centre point M to the respective adjacent column, is preferably between 2° and 60°, preferably between 5° and 35° and particularly preferably between 10° and 25°. The angle B between two adjacent columns is preferably between 0.5° and 30°, preferably between 0.8° and 25° and particularly preferably between 1° and 20°. Preferably, the angle A can also be dependent on the diameter of the container or be in a ratio X to the container diameter. The ratio X can preferably be between 0 and 10.
(45) The reference sign R indicates the radius of the base part and the reference signs C-E indicate the distances between the holes along a row or column 44. The radius R is preferably either in a ratio RD to the container diameter or in a ratio RS to a standing circle diameter of the bottom. The ratio RD can range between 0 and 1, preferably between 0.25 and 0.90. The ratio RS can range between 0 and 2, preferably between 0.5 and 1.5.
(46) The distances C, D and E are preferably in a ratio RA to the radius R. The distances C, D and E preferably all have the same ratio to the radius R. However, it is conceivable that the dimensions C, D and E are in different ratios to the radius R.
(47) For example, the distance C: C=RAC*R
(48) For example, the distance D: D=RAD*R
(49) For example, the distance E: E=RAE*R
(50) FIG. 22 shows a further exemplary hole pattern 40 of a section of the base part. The individual holes 23 are here again arranged in several columns 44 and rows 42, wherein the columns 44 being marked with the numbers 20-28 and the rows with the numbers 1-10. The columns 44 are thereby preferably arranged in radial direction to a centre point M of the base part and the rows 42 in circumferential direction of the base part. The individual holes 32 within a hole pattern 40 may preferably have the same diameter or a different diameter. The holes 32, if different in size, are preferably in a ratio BD to each other which is between 0.25 and 10, preferably between 0.5 and 6.
(51) FIGS. 23-26 show further exemplary hole patterns 40 of a section of the base part. Again, a plurality of holes 32 are arranged in several columns 44 and rows 42. The respective hole pattern 40 can consist of any number of holes 32, which have either the same or different diameters.
(52) The applicant reserves the right to claim all features disclosed in the application documents as essential to the invention, provided they are individually or in combination new compared to the prior art. It is further pointed out that the individual figures also describe features which may be advantageous in themselves. The skilled person immediately recognises that a certain feature described in a figure can also be advantageous without adopting further features from this figure. Furthermore, the skilled person recognises that advantages can also result from a combination of several features shown in individual figures or in different figures.
LIST OF REFERENCE SIGNS
(53) 1 blow mould 2, 4 side parts 6 base part 6a-6e sections of the base part 10 plastic preforms 12, 14 support shells 18 cavity 20 plastic containers 22, 24 blow mould carrier 30 openings 32 hole, bore 33 slot 34 series 35 outer surface 36 channel 38 spline 40 hole pattern 42 lines 44 columns 50 forming device 52 forming station 54 rotatable carrier 55 feed device 57 discharge starwheel 60 vacuum generation device A angle B angle C distance D distance E distance M centre point R radius
