CN111531846A - Special-shaped section bottle blank structure and forming method thereof - Google Patents

Special-shaped section bottle blank structure and forming method thereof Download PDF

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Publication number
CN111531846A
CN111531846A CN202010518413.4A CN202010518413A CN111531846A CN 111531846 A CN111531846 A CN 111531846A CN 202010518413 A CN202010518413 A CN 202010518413A CN 111531846 A CN111531846 A CN 111531846A
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China
Prior art keywords
section
special
bottle
shaped
bottle blank
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CN202010518413.4A
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Chinese (zh)
Inventor
谢国基
姜晓平
胡青春
罗国泉
陈境钰
卢佳
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GDXL Precise Machinery Co Ltd
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GDXL Precise Machinery Co Ltd
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Priority to CN202010518413.4A priority Critical patent/CN111531846A/en
Publication of CN111531846A publication Critical patent/CN111531846A/en
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C49/00—Blow-moulding, i.e. blowing a preform or parison to a desired shape within a mould; Apparatus therefor
    • B29C49/071—Preforms or parisons characterised by their configuration, e.g. geometry, dimensions or physical properties
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C45/00—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
    • B29C45/17—Component parts, details or accessories; Auxiliary operations
    • B29C45/72—Heating or cooling
    • B29C45/7207—Heating or cooling of the moulded articles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C49/00—Blow-moulding, i.e. blowing a preform or parison to a desired shape within a mould; Apparatus therefor
    • B29C49/02—Combined blow-moulding and manufacture of the preform or the parison
    • B29C49/06—Injection blow-moulding
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C49/00—Blow-moulding, i.e. blowing a preform or parison to a desired shape within a mould; Apparatus therefor
    • B29C49/02—Combined blow-moulding and manufacture of the preform or the parison
    • B29C2049/023—Combined blow-moulding and manufacture of the preform or the parison using inherent heat of the preform, i.e. 1 step blow moulding

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  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Geometry (AREA)
  • Containers Having Bodies Formed In One Piece (AREA)

Abstract

The invention discloses a special-shaped section bottle blank structure and a forming method thereof, wherein a blank body of the special-shaped section bottle blank structure comprises an annular section, a section changing section and a special-shaped section, the special-shaped section has a special-shaped section, the shortest distance between an inner closing line and an outer closing line of the special-shaped section is the wall thickness of the bottle blank structure, the outer closing line and the inner closing line are corrugated lines, compared with the annular section bottle blank structure with the same length and the same gram weight of the special-shaped section bottle blank structure, the circumference of the special-shaped section is larger than the circumference of the annular section on the premise that the bottle blowing stretch ratio of the special-shaped section bottle blank structure is equal to the bottle blowing stretch ratio of the annular section bottle blank structure, and the wall thickness of the special-shaped section bottle blank structure is smaller than the. The special-shaped cross-section bottle blank structure can effectively shorten the cooling time of the injection molding of the bottle blank and the preheating time before bottle blowing, thereby shortening the whole processing period of the bottle and improving the production efficiency.

Description

Special-shaped section bottle blank structure and forming method thereof
Technical Field
The invention relates to the technical field of bottle blanks, in particular to a bottle blank structure with a special-shaped cross section and a forming method thereof.
Background
Due to the characteristics of high efficiency and manufacturability of injection molding, injection molding has become the most common method for manufacturing plastic products, and has a very important position in the plastic processing industry. The cooling is the most important stage in the injection molding process, and has a great influence on the quality and the production efficiency of the product, the cooling time occupies about 2/3 of the whole injection molding time, and the cooling time is a key influence on the product forming period and the energy consumption. At present, the research on the cooling technology for accelerating the formed part at home and abroad mainly focuses on accelerating the heat dissipation part of the mold, however, because the heat conductivity coefficient of the bottle blank material is extremely small, the self heat resistance is far greater than the heat resistance of a cooling system and the mold in the cooling process, the self heat resistance of the bottle blank is the main factor influencing the cooling efficiency, and the reduction of the cooling time is substantially limited by improving the heat exchange coefficient of cooling water and the heat conductivity coefficient of the mold material in the prior art.
Disclosure of Invention
In order to solve the defects of the prior art, the invention provides a bottle blank structure with a special-shaped cross section and a forming method thereof.
In order to achieve the purpose, the invention adopts the following technical scheme:
a bottle blank structure with a special-shaped section comprises a bottle mouth, a blank body and a blank bottom, wherein the blank body comprises an annular section, a section changing section and a special-shaped section, the annular section is connected with the bottle mouth, the special-shaped section is connected with the blank bottom, the section changing section is a transition section between the annular section and the special-shaped section,
the special-shaped section is provided with a special-shaped section, the special-shaped section is composed of an inner closing line and an outer closing line, the shortest distance between the inner closing line and the outer closing line is the wall thickness of the bottle blank structure, the outer closing line and the inner closing line are corrugated lines and comprise a plurality of wave crests and wave troughs,
compared with the annular-section bottle blank structure with the same length and the same gram weight of the special-shaped-section bottle blank structure, the annular-section bottle blank structure is provided with the annular section, the circumference of the special-shaped section is larger than that of the annular section on the premise that the bottle blowing stretching ratio of the special-shaped-section bottle blank structure is equal to the bottle blowing stretching ratio of the annular-section bottle blank structure, and the wall thickness of the special-shaped-section bottle blank structure is smaller than that of the annular-section bottle blank structure.
The invention also provides a forming method of the bottle blank structure with the special-shaped section, which comprises the following steps:
s1 provides a conventional bottle blank structure, which comprises a bottle mouth, a blank body and a blank bottom, wherein the blank body is hollow and cylindrical and has a circular cross section consisting of an outer closed line and an inner closed line, the outer diameter and the inner diameter of the circular cross section are m and n respectively, and the area of the circular cross section is SRing (C)；
S2 changing the outer closed line and the inner closed line of the circular ring-shaped cross-section into a corrugated line having a plurality of peaks and valleys, thereby forming a deformed cross-section composed of the outer corrugated line and the inner corrugated line,
specifically, the number of wave crests is preset, an included angle theta between the wave crests and a connecting line of wave troughs and the center of the circular ring shape is obtained, and a special-shaped section model is established on the premise that the area of the special-shaped section is not changed relative to the area of the circular ring-shaped section;
s3, obtaining a bottle blank structure with a special-shaped section according to the special-shaped section model, wherein the gram weight and the bottle blowing stretch ratio of the bottle blank structure with the special-shaped section are equal to those of the conventional bottle blank structure, but the section perimeter of the bottle blank structure with the special-shaped section is larger than that of the conventional bottle blank structure, and the wall thickness of the bottle blank structure with the special-shaped section is smaller than that of the conventional bottle blank structure.
The invention improves the conventional bottle blank structure with the annular cross section in the prior art, keeps the length and the gram weight of the bottle blank unchanged while improving, changes the bottle blank structure with the annular cross section into the bottle blank structure with the special-shaped cross section, and compared with the annular cross section of the bottle blank structure with the annular cross section, the special-shaped cross section of the bottle blank structure with the special-shaped cross section has the same cross section area, increased cross section circumference and reduced bottle blank wall thickness, and the characteristics of the invention ensure that the bottle blank structure with the special-shaped cross section has the following beneficial effects:
(1) because the circumference of the section is increased, the contact area of the bottle blank and the blowing mold is increased, thereby shortening the cooling time of injection molding of the bottle blank, shortening the whole injection molding period and improving the production efficiency of the bottle blank;
(2) the wall thickness of the bottle blank is reduced, so that the heat conductivity of the bottle blank is better, the bottle blank is more uniformly preheated before blow molding, and the heating time is shortened, so that the energy consumption in the preheating process is reduced;
(3) the invention changes the bottle blank structure with the annular section into the bottle blank structure with the special-shaped section, but the stretch ratio of the bottle blank is kept unchanged, so the blow molding performance of the bottle blank is not changed, and the quality of a bottle formed by blow molding is not influenced.
Drawings
The present invention will be further described and illustrated with reference to the following drawings.
Fig. 1a is a schematic representation of a prior art bottle preform.
FIG. 1b is a cross-sectional view A-A of FIG. 1 a.
Fig. 2 is a schematic diagram of the structure of the bottle preform with the irregular cross section of the invention.
Fig. 3a is a cross-sectional view of a profiled cross-section of the profiled cross-section preform structure of fig. 2.
Fig. 3b is a schematic diagram of the modeling of the profiled cross-section of fig. 3 a.
Detailed Description
The technical solution of the present invention will be more clearly and completely explained by the description of the preferred embodiments of the present invention with reference to the accompanying drawings.
The prior art shown in fig. 1a and 1b is a conventional preform structure, and the conventional preform structure 10 ' includes a bottle opening 1 ', a body 2 ', and a base 3 ', and the body 2 ' is located between the bottle opening 1 ' and the base 3 '. As shown in fig. 1b, when the blank 2 ' has a circular cross section, the outer diameter of the circular cross section is m, the inner diameter of the circular cross section is n, the thickness t ' of the blank 2 ' is m-n, and the area of the circular cross section is:
Figure BDA0002530990300000031
in order to shorten the cooling time of plastic bottle injection molding, the invention researches and designs the shape of a bottle blank structure.
As shown in fig. 2, the bottle preform structure 20 with a special-shaped cross section of the present invention includes a bottle mouth 1, a preform body 2, and a preform bottom 3, wherein the preform body 2 is located between the bottle mouth 1 and the preform bottom 3. Specifically, the blank body 2 includes a ring-shaped section 21, a section changing section 22, and a deformed section 23. Wherein, the ring-shaped section 23 is connected with the bottle mouth 1 and has a ring-shaped section shape; the shaped section segment 23 is connected to the blank bottom 3 and has a shaped cross-sectional shape, where "shaped" is a cross-sectional shape different from the circular cross-sectional shape with respect to the circular shape; the cross-sectional variation 22 is a transition between the annular cross-sectional section 21 and the profiled cross-sectional section 23, which transitions from a circular shape to a profiled contour.
The blank bottom 3 comprises an arc changing section 31 and a spherical section 32, wherein the arc changing section 31 is connected with the special-shaped section 23, gradually changes from a special-shaped contour to a circular contour, and is in arc transition connection with the spherical section 32. The maximum diameter d of the spherical segment 32 is not less than φ 8.
The principle of shortening the cooling time of injection molding of the invention is as follows: on the premise of not changing the gram weight of the conventional bottle blank, the cross section perimeter of the bottle blank structure is increased and the wall thickness of the bottle blank is reduced by changing the cross section shape of the bottle blank, so that the contact area between the bottle blank and a bottle blowing mold is substantially increased, the cooling time is shortened, the injection molding period and even the whole production period are shortened, the energy consumption is reduced, and the production efficiency is improved.
Based on the principle, the invention provides the following concrete implementation modes of the bottle blank structure with the special-shaped section:
as shown in fig. 3a and 3b, in this embodiment, the cross-sectional shape of the shaped cross-sectional section 23 is formed by an outer closed line 210b and an inner closed line 220b, both the outer closed line 210b and the inner closed line 220b are corrugated, and the outer closed line 210b and the inner closed line 220b formed by the corrugated lines include a plurality of peaks 211b, 221b and valleys 212b, 222 b.
The ripple shape in this embodiment is substantially composed of a plurality of arc segments, the number of ripples is determined by the included angle corresponding to the arc segments, and the amplitude of the ripples is directly influenced by the position and the diameter of the center of the arc. As shown in fig. 3b, a method for generating a curve model will be described below by taking one of the curves as an example.
In order to ensure that the stretch ratio of the bottle preform structure with the irregular cross section is equal to that of the bottle preform structure with the circular cross section shown in fig. 1a and 1b, the outer closed line 210b and the inner closed line 220b are respectively positioned near the outer circular ring and the inner circular ring of the circular cross section, preferably, the outer corrugated line (i.e. the outer closed line 210b) and the inner corrugated line (i.e. the inner closed line 220b) are respectively distributed on the outer circular ring and the inner circular ring, and the area of the cross section (hereinafter referred to as the "inner and outer corrugated cross section") formed by the corrugated outer closed line 210b and the inner closed line 220b and the area S of the circular cross section are respectively equal to that of theRing (C)Equals to give the number of wave crests x, D1、D2、D3、D4The unique corrugated section can be obtained by the three values, and the number x and D of wave crests are preset1、D2Obtaining D through the special-shaped section model3、D4、D5、D6。
Wherein D is1Represents the distance from the center of the circular cross section to the center of the wave crest of the inner corrugated line, D2Indicating the distance D from the center of the circular cross-section to the center of the trough of the outer corrugated line3Showing the trough diameter of the outer corrugation line, D4Showing the valley diameter of the inner wavy line, D5Denotes the crest diameter of the inner wavy line, D6The peak diameter of the outer corrugation lines is indicated.
The process of establishing the model of the inner and outer corrugated sections is as follows:
Figure BDA0002530990300000041
Figure BDA0002530990300000042
Figure BDA0002530990300000043
Figure BDA0002530990300000044
Figure BDA0002530990300000045
Figure BDA0002530990300000046
radius of the left end and the right end of the outer corrugation:
Figure BDA0002530990300000047
external corrugation tip radius:
Figure BDA0002530990300000048
order to
Figure BDA0002530990300000049
Wherein m and n are respectively the outer diameter and the inner diameter of the annular section bottle blank structure.
Circle D4And D5Tangency, the sum of radii equal AB:
Figure BDA00025309903000000410
2-8 to 2-11 in a united vertical manner
Figure BDA0002530990300000051
Figure BDA0002530990300000052
The corrugated cross-sectional area is:
Figure BDA0002530990300000053
the corrugated section has the same area as the section of the circular ring:
Swave (wave)＝SRing theta(2-15)
Circle D3And D6Tangency, the sum of radii equal AB:
Figure BDA0002530990300000054
2-2, 2-14 to 2-16 have
Figure BDA0002530990300000055
Order to
Figure BDA0002530990300000056
Then there is
Figure BDA0002530990300000057
Figure BDA0002530990300000058
D3＝2AB-D6(2-21)
The thickness of the corrugation is:
Figure BDA0002530990300000059
thus, a model of the inner and outer corrugated cross-section was obtained.
According to the invention, the conventional bottle blank structure with the annular section is improved, and the annular section of the bottle blank structure with the annular section is changed into the special-shaped section on the premise of not changing the gram weight of the bottle blank, so that the section perimeter of the bottle blank structure is increased, the contact area between the bottle blank and a bottle blowing mold is substantially increased, and the cooling time of injection molding of the bottle blank can be effectively shortened; and the wall thickness of the bottle blank with the special-shaped cross section is reduced compared with that of the bottle blank with the conventional annular cross section, so that the bottle blank with the special-shaped cross section has better heat conductivity, when the bottle blank is blown into a bottle, the bottle blank is uniformly preheated, the heating time is shortened, and the energy consumption of heating the bottle blank and the energy consumption of bottle blowing pressure are reduced. In addition, the change of the sectional shape of the bottle blank does not affect the stretch ratio of the bottle blank, and the stretch ratio is kept unchanged from the original conventional bottle blank, so that the blow molding property of the bottle is kept unchanged, and the bottle with the same quality requirement can be formed by blow molding.
The above detailed description merely describes preferred embodiments of the present invention and does not limit the scope of the invention. Without departing from the spirit and scope of the present invention, it should be understood that various changes, substitutions and alterations can be made herein by those skilled in the art without departing from the spirit and scope of the invention as defined by the appended claims and their equivalents. The scope of the invention is defined by the claims.

Claims (7)

1. The utility model provides a dysmorphism cross section bottle base structure, includes at the bottom of bottleneck, base body, the base, its characterized in that:
the blank body comprises an annular section, a section change section and a special-shaped section, the annular section is connected with the bottle mouth, the special-shaped section is connected with the blank bottom, the section change section is a transition section between the annular section and the special-shaped section,
the special-shaped section is provided with a special-shaped section, the special-shaped section is composed of an inner closing line and an outer closing line, the shortest distance between the inner closing line and the outer closing line is the wall thickness of the bottle blank structure, the outer closing line and the inner closing line are corrugated lines and comprise a plurality of wave crests and wave troughs,
compared with the annular-section bottle blank structure with the same length and the same gram weight of the special-shaped-section bottle blank structure, the annular-section bottle blank structure is provided with an annular section, the circumference of the special-shaped section is larger than that of the annular section on the premise that the bottle blowing stretching ratio of the special-shaped-section bottle blank structure is equal to the bottle blowing stretching ratio of the annular-section bottle blank structure, and the wall thickness of the special-shaped-section bottle blank structure is smaller than that of the annular-section bottle blank structure.
2. The shaped cross-section preform structure of claim 1, wherein the shaped cross-section of the shaped cross-section preform structure has an area equal to an area of the annular cross-section preform structure.
3. The odd-shaped cross-section bottle preform structure as claimed in claim 2, wherein the lines of corrugation constituting the outer closed line and the inner closed line are distributed on the outer circular ring and the inner circular ring of the circular cross-section, respectively.
4. The profiled cross-section bottle preform structure of claim 1, wherein said preform base comprises a circular arc variation section and a spherical section, said circular arc variation section being connected to said profiled cross-section.
5. A method for forming a bottle blank structure with a special-shaped section is characterized by comprising the following steps:
s1 provides a conventional bottle blank structure, the conventional bottle blank structure includes a bottle mouth, a blank body and a blank bottom, the blank body is hollow cylindrical and has a circular section formed by an outer closed line and an inner closed line, the outer diameter and the inner diameter of the circular section are m and n respectively, and the area of the circular section is SRing (C)；
S2, changing the outer closed line and the inner closed line of the circular ring-shaped section into a corrugated line which has a plurality of wave crests and wave troughs, thereby forming a special-shaped section consisting of the outer corrugated line and the inner corrugated line,
specifically, presetting the number x of wave crests to obtain an included angle theta between the central connecting line of the wave crests and the wave troughs and the circular ring shape, and establishing a special-shaped section model on the premise of ensuring that the area of the special-shaped section is not changed relative to the area of the circular ring-shaped section;
s3, obtaining a bottle blank structure with a special-shaped section according to the special-shaped section model, wherein the gram weight and the bottle blowing stretch ratio of the bottle blank structure with the special-shaped section are equal to those of the conventional bottle blank structure, but the section perimeter of the bottle blank structure with the special-shaped section is larger than that of the conventional bottle blank structure, and the wall thickness of the bottle blank structure with the special-shaped section is smaller than that of the conventional bottle blank structure.
6. The method for forming a shaped cross-section bottle preform structure as recited in claim 5, wherein in the step S2, the outer corrugation lines and the inner corrugations are caused to extend on the outer circular ring and the inner circular ring of the circular ring-shaped cross-section, respectively.
7. The method for forming a bottle preform structure with a modified cross-section as claimed in claim 6, wherein in the step S2, a distance D from the center of the circular cross-section to the center of the peak of the inner corrugated line is preset1And the distance D from the center of the circular cross section to the center of the trough of the outer corrugated line2Obtaining the trough diameter D of the outer corrugated line through the special-shaped section model3The crest diameter D of the outer crest line6The trough diameter D of the inner corrugated wire4Crest diameter D of inner crest line5。
CN202010518413.4A 2020-06-09 2020-06-09 Special-shaped section bottle blank structure and forming method thereof Pending CN111531846A (en)

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Application Number Priority Date Filing Date Title
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Application Number Priority Date Filing Date Title
CN202010518413.4A CN111531846A (en) 2020-06-09 2020-06-09 Special-shaped section bottle blank structure and forming method thereof

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