CN112873809A

CN112873809A - Method for optimizing structure of bottle blank

Info

Publication number: CN112873809A
Application number: CN201911210186.2A
Authority: CN
Inventors: 齐珊; 杨杰; 赵楠; 巴根纳
Original assignee: Inner Mongolia Yili Industrial Group Co Ltd
Current assignee: Inner Mongolia Yili Industrial Group Co Ltd
Priority date: 2019-11-29
Filing date: 2019-11-29
Publication date: 2021-06-01

Abstract

A method of optimizing the structure of a preform comprising the steps of: (1) drawing a plurality of lines which are mutually spaced along the outer wall of the bottle blank; (2) blow molding to obtain a finished bottle product; (3) determining the corresponding positions of all parts on the bottle blank according to the position of each line on the finished bottle product; (4) measuring the thickness distribution of each part of the finished bottle product, and judging the part of the bottle blank needing thickening or thinning; (5) blow molding the thickened or thinned bottle blank; (6) and (5) repeating the steps (4) and (5) until the thickness distribution of each part of the finished bottle product reaches the qualified standard. The method can quickly find the position of the bottle shape corresponding to the bottle blank, thereby modifying the structure of the corresponding position according to actual needs and finally achieving the purpose of optimizing the required performance of the bottle or reducing weight.

Description

Method for optimizing structure of bottle blank

Technical Field

The invention belongs to the technical field of blow molding container forming, and particularly relates to a method for optimizing a bottle blank structure.

Background

In the process of preparing the bottle by the blow molding process, the structure of the bottle blank has an important influence on the forming quality of the bottle, and with the increasing diversification of the shapes of the bottle, more requirements are put on the structure of the bottle blank. For example, some parts of the bottle are stressed more greatly, and the thickness needs to be increased, while some parts are stressed less, and the thickness can be reduced to achieve the purpose of reducing weight. However, in the process of blowing the bottle, the shape and structure of the bottle preform are changed continuously, and different parts of the molded bottle often cannot directly correspond to the parts of the bottle preform, which brings great difficulty to the structural design of the bottle preform.

In the design process of the prior bottle blank (such as weight reduction, thickening and other structural optimization), the sample bottle blank is required to be adjusted and manufactured repeatedly for bottle blowing test until the modification is satisfactory. The work is heavy and time and labor consuming, and the results are also unsatisfactory. Therefore, a method for rapidly optimizing the bottle blank structure is urgently needed to meet the requirements of different bottle types.

Disclosure of Invention

In order to overcome the defects and shortcomings in the prior art, the invention provides a method for optimizing the structure of a bottle blank, which can quickly determine the structures of all parts of the bottle blank corresponding to one bottle type, finally optimize the required performance of a bottle and effectively save the time and cost of the bottle blank optimization work.

In order to achieve the purpose, the invention adopts the following technical scheme:

a method of optimizing the structure of a preform comprising the steps of:

(1) drawing a plurality of lines which are mutually spaced along the outer wall of the bottle blank;

(2) blow molding to obtain a finished bottle product;

(3) determining the corresponding positions of all parts on the bottle blank according to the position of each line on the finished bottle product;

(4) measuring the thickness distribution of each part of the finished bottle product, and judging the part of the bottle blank needing thickening or thinning;

(5) blow molding the thickened or thinned bottle blank;

(6) and (5) repeating the steps (4) and (5) until the thickness distribution of each part of the finished bottle product reaches the qualified standard.

In some embodiments, the wires are spaced 1-10mm apart, such as 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, or 9 mm.

In some embodiments, the number of lines is 5-20 (e.g., 6, 7, 8, 9, 10, 12, 15, 18, etc.).

In some embodiments, each line is a circumferential line perpendicular to the axis of the preform.

In some embodiments, the color of the thread is different from the color of the preform.

In some embodiments, the spacing between the lines of the more deformed regions during the blow molding process is less than the spacing between the lines of the less deformed regions.

In some embodiments, the thickness distribution of the various portions of the finished bottle is measured by subjective grip testing, light illumination, or magnetic thickness gauges.

In some embodiments, the total weight of the preform remains unchanged during the optimization of the structure of the preform.

Compared with the prior art, the method for quickly optimizing the structure of the bottle blank provided by the invention has the following beneficial effects:

the method can quickly find the position of the bottle shape corresponding to the bottle blank, thereby modifying the structure of the corresponding position according to actual needs and finally achieving the purpose of optimizing the required performance of the bottle or reducing weight.

Drawings

FIG. 1 is a schematic view of a preform in an embodiment of the present invention;

FIG. 2 is a schematic view of a finished bottle in an embodiment of the present invention;

FIG. 3 is a partial schematic view of a preform in an embodiment of the present invention;

fig. 4 is a comparison of wall thickness distribution of finished bottles before and after optimization of preform structures in embodiments of the invention.

Description of reference numerals:

1-a bottleneck section; 2-bottleneck section; 3-a bottle body section; 4-bottle bottom section.

Detailed Description

In order that the objects, technical solutions and advantages of the present invention will become more apparent, the present invention will be further described in detail with reference to the accompanying drawings in conjunction with the following specific embodiments.

In the description of the present invention, reference to "one embodiment" means that a particular feature, structure, or parameter, step, or the like described in the embodiment is included in at least one embodiment according to the present invention. Thus, appearances of the phrases such as "in one embodiment," "in one embodiment," and the like in this specification are not necessarily all referring to the same embodiment, nor are other phrases such as "in another embodiment," "in a different embodiment," and the like. Those of skill in the art will understand that the particular features, structures or parameters, steps, etc., disclosed in one or more embodiments of the present description may be combined in any suitable manner.

In the description of the present invention, the terms "left", "right", "inside", "outside", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention.

In the description of the present invention, it is to be noted that the terms "connected" and "connected," unless otherwise explicitly specified or limited, are to be construed broadly, e.g., as directly connected or indirectly connected through an intermediate. The specific meaning of the above terms in the present invention can be understood as appropriate by those of ordinary skill in the art.

Fig. 1 shows a bottle blank structure in an embodiment of the present invention, which is a bottle mouth section 1, a bottle neck section 2, a bottle body section 3 and a bottle bottom section 4 connected in sequence from left to right, each section includes an inner wall and an outer wall, a thread may be arranged on the bottle mouth section 1, and under normal circumstances, the bottle mouth section 1 is the same as the bottle mouth of a finished bottle product, and does not change during a bottle blowing process.

The neck section 2 is used for connecting the mouth section 1 and the body section 3, and is usually circular arc-shaped, the body section 3 is usually straight line-shaped, and the bottom section 4 is usually circular arc-shaped, and according to the shape of the finished bottle, the neck section 2, the body section 3 and the bottom section 4 of the bottle blank may be the same or different in thickness, for example, may gradually become thick or thin along a certain direction.

Through the bottle blowing process, the bottle blank structure in fig. 1 can be made into the finished bottle product shown in fig. 2. The stress condition and the effect of each part of the finished bottle are different in the using process, for example, the stress of the bottom of the bottle is usually the largest and generally needs to have the largest strength, the joints among different shapes also generally need to have certain strength so as to avoid deformation caused by unbalanced stress, and the thickness of the parts which are less stressed and not easy to deform can be reduced generally, so that the whole weight of the bottle is reduced. In the optimization process of the bottle blank structure, the sample bottle blank is usually required to be repeatedly manufactured, the bottle blowing test is carried out after the thickness of each part is continuously adjusted, the workload is large, and the time and the labor are consumed.

The invention adopts a method of marking and positioning on the bottle blank, a plurality of lines with certain intervals are marked on the bottle blank, and the bottle blank is subdivided into a plurality of parts. And then blowing the bottle under a normal process, wherein the corresponding relation between the position of the bottle blank and the position of the bottle shape can be determined according to the positions of the marked lines on the bottle blank and the finished bottle product, namely the corresponding part of the bottle blank can be modified aiming at the position of the weak part (such as the position needing thickening) of the existing bottle shape performance or the position capable of reducing weight, and the structure of the corresponding position of the bottle blank is optimized, so that the aim of optimizing the performance of the bottle is fulfilled.

In the invention, the improvement of the bottle performance is mainly carried out by thickening or thinning the bottle wall at the corresponding position, and the aim of optimizing various performances of the bottle can be achieved by adjusting the thickness distribution of the bottle wall, for example, if the wall thickness of the bottle bottom is too thin, the risk of falling and breaking exists in the circulation process, so the wall thickness of the part needs to be increased, and for example, if the wall thickness distribution of each part of the bottle body is not uniform, some parts are thick, some parts are thin, the risk of falling and breaking exists at the thin parts, and the hand feeling experience of consumers is poor.

Specifically, the method for optimizing the structure of the bottle blank provided by the invention comprises the following steps:

(2) blow molding to obtain a finished bottle product;

(5) blow molding the thickened or thinned bottle blank;

As shown in fig. 1, the plurality of lines drawn are distributed on the outer walls of the neck section 2, the body section 3 and the bottom section 4, each line is a circumferential line perpendicular to the axis of the bottle preform, the interval between the lines can be determined according to the shape and size of the bottle preform and the finished bottle product, the bottle blowing process and other factors, and the interval between the lines can be the same or different, and in some embodiments of the present invention, the interval between the lines can be 1-10mm, for example, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm or 9 mm.

The number of lines is not limited and can be, for example, 5-20 lines (e.g., 6, 7, 8, 9, 10, 12, 15, 18, etc.), and theoretically, the denser the lines are, the more precise the corresponding positions of the preform and the bottle are found, and the more precise the later analysis is. In general, in the bottle blowing process, the position with larger deformation has smaller intervals between lines to improve the analysis precision, and in the bottle blowing process, the position with smaller deformation has appropriately increased intervals between lines to reduce the working strength. As shown in fig. 1, the lines on neck section 2 are spaced less apart, while the lines on body section 3 are spaced more apart.

For identification, the color of each thread is preferably different from the color of the bottle blank, for example, in some cases, the material of the bottle is Polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), etc., the bottle itself is colorless or transparent, and the thread color may be black, red, blue, purple, etc.

The method for determining that each part needs to be thickened or thinned comprises the following steps:

for non-transparent bottles: the thickness uniformity of the bottle from top to bottom can be subjectively sensed through the holding feeling; or the bottle is directly illuminated from the bottle opening by using a light source, the thickness of the bottle can be sensed by naked eyes in the dark, the light transmission in the thin part is obvious, and the light transmission in the thick part is weaker; or the actual wall thickness data of different positions of the bottle body can be measured by using a magnetic thickness gauge.

For a transparent bottle body, the thickness distribution condition of the bottle is not suitable to be judged by adopting an illumination method, and the thickness uniformity of the bottle from top to bottom can be subjectively sensed through the holding feeling; or measuring actual wall thickness data of different positions of the bottle body by using a magnetic thickness gauge.

Example 1

In one embodiment of the invention, the wall thickness of the neck portion of the preform is optimized. As shown in fig. 3, the neck portion includes 4 lines, which is the weakest part of the bottle performance structure, i.e. the wall thickness is relatively low, and the purpose of optimizing the structure can be achieved by modifying the design of the corresponding part on the bottle blank.

As shown in fig. 4, before the bottle blank is optimized, the thicknesses of the finished bottle at the positions of 4 lines are respectively 0.332mm, 0.28mm, 0.27mm and 0.364mm, the light transmittance of the neck section is found to be larger than that of the lower half part of the bottle through direct illumination from the bottle opening by using a light source, and the thickness distribution of the bottle is found to be very uneven by measuring the thickness data of different positions of the bottle body by using a magnetic thickness gauge.

In the process of optimizing the bottle blank, the thicknesses of the bottle blank at the 3 rd line position and the 4 th line position are gradually increased, as shown in fig. 3, the dotted line is the inner wall before optimization, the solid line is the inner wall after optimization, thickness tests of the bottle body at different positions are carried out by a magnetic thickness gauge after blow molding, and the results show that the thicknesses of the finished bottle product at the 4 line positions are respectively 0.363mm, 0.344mm, 0.38mm and 0.45mm, and it can be seen that the wall thickness of the finished bottle product at the bottleneck section is obviously higher than that of the bottle product at the corresponding position before optimization. The direct illumination test of the light source from the bottle opening finds that the thickness distribution of the bottle is uniform before optimization.

In the embodiment, the original bottle blank is modified and tested twice, so that the bottle which meets the expectation is obtained, and the optimization efficiency is greatly improved.

Example 2

In another embodiment of the invention, through direct illumination from the bottle opening by using a light source, the light transmittance of the upper part of the bottle body section is found to be smaller than that of the lower part of the bottle body section, namely, the upper part of the bottle body section is thicker, and the lower part of the bottle body section is thinner, and the thickness data of different positions of the bottle body measured by using a magnetic thickness gauge is found to be very uneven in thickness distribution of the bottle. The preform was optimized in the same manner as in example 1 by drawing 12 lines across the entire body segment, with equal distances between the lines.

In this embodiment, in order to maintain the total weight of the preform constant, the thickness of the upper portion of the body section is reduced, and the preform removed from the upper portion of the body section is added to the lower portion of the body section. The original bottle blank is modified and tested three times, and the expected bottle is obtained.

In conclusion, the method of the invention can quickly find the position of the bottle shape corresponding to the bottle blank, thereby modifying the structure of the corresponding position according to actual needs and finally achieving the purpose of optimizing the required performance of the bottle or reducing weight.

The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that the above-mentioned embodiments are only exemplary embodiments of the present invention and are not intended to limit the present invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method of optimizing the structure of a preform, comprising the steps of:

(2) blow molding to obtain a finished bottle product;

(5) blow molding the thickened or thinned bottle blank;

2. A method of rapidly optimising the structure of a preform according to claim 1 wherein the spacing of the lines is between 1 and 10mm, such as 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm or 9 mm.

3. The method for rapidly optimizing the structure of a preform according to claim 1 or 2, wherein each line is a circumferential line perpendicular to the axis of the preform.

4. The method for rapidly optimizing the structure of preforms according to claim 1 or 2, wherein the colour of the thread is different from the colour of the preforms.

5. The method for rapidly optimizing the structure of a preform according to claim 1 or 2, wherein the number of lines is 5-20 (e.g. 6, 7, 8, 9, 10, 12, 15, 18).

6. The method for rapidly optimizing the structure of a preform according to claim 1, wherein the interval between the lines of the portion where deformation is large is smaller than the interval between the lines of the portion where deformation is small during the blow molding process.

7. The method for rapidly optimizing the structure of a bottle preform according to claim 1, wherein in the step (4), the thickness distribution of each part of the finished bottle product is tested by a subjective grip feeling test, an illumination method or a magnetic thickness gauge.

8. The method for rapidly optimizing the structure of a bottle preform according to claim 1, wherein the total weight of the bottle preform is maintained constant during the optimization of the structure of the bottle preform.