CN1022748C

CN1022748C - Intermediate article of wide mouth container

Info

Publication number: CN1022748C
Application number: CN 91111845
Authority: CN
Inventors: 杜纳德·L·格林沃德; 杜纳德·W·海沃德
Original assignee: Sonoco Products Co
Current assignee: Sonoco Products Co
Priority date: 1987-12-07
Filing date: 1988-12-07
Publication date: 1993-11-17
Anticipated expiration: 2003-12-07
Also published as: CN1062702A

Abstract

This invention provides a wide mouth container and intermediate article formed by stretch blow-molding an injection-molded preform of polyethylene terephthalate suitable for packaging tennis balls or other contents under pressure. The container includes an improved base construction which will withstand internal pressure with controlled minimal distortion and an improved flange construction surrounding the wide mouth which provides desired strength and thickness for receiving a metal end closure by double seaming operations and which is formed by a unique accommodation portion in the intermediate article which has a stepped wall construction.

Description

Intermediate article of wide mouth container

The invention relates to a kind of large container, the intermediate that is formed by polyethylene terephthalate (polyethylene terephthalate is PET) injection molding precast body stretch blow-molded, this container is suitable for packing tennis or other article under certain pressure.It has improved uncovered circumferential flange structure, and this flange is formed by adjustment member unique on the intermediate, and it has enough intensity and thickness, and metal end can be engaged thereon with double seam.

As US Patent 3,733,309 is disclosed, and when production press packet packaging container, the molecule twin shaft arrangement preferably with blowing moulding produces can make many material properties of PET improve.In real process, the design of injection molding preformed part is; Preformed part is placed in its volume mold cavity identical with required intermediate, preformed part longitudinally stretches in mould, then with high pressure gas with the shape of the horizontal inflation of preformed part to intermediate and mold cavity, molecule all rearranges on the both direction of container like this.

The bottom of the Vessel Design that existing P ET molecule twin shaft is arranged not pressure-bearing commonly used is especially in the container of containing the carbonated drink beverage, so that its strength and stiffness are enough to bear longitudinal pressure.Independently the form at the bottom of the resistance to compression can be divided into Petaloid type (US Patent 3,598,270) and Champagne type (US Patent 4,465,199), but in the PET stretch blow-molded, be difficult at the bottom of these two kinds form,, PET material extending and inflation arrived and the required annular space of determining because they need moving of higher blowing mould pressure and/or two apotypes.

Equally, in the PET of wide-mouth stretch blow-molded container, also need its flange punishment that twin shaft arrangement is preferably arranged, make it around uncovered, radially outward locate enough intensity and thickness, be convenient in double seam seam mode, under certain pressure, seal being placed with as the PET stretch blow-molded container of article such as tennis with metal end.In US Patent 4,496, flanged PET stretch blow-molded large container is disclosed in 064 and 4,567,843.The twin shaft that it needs entire container all to have molecule is arranged, to satisfy performance requriements.The formation of wherein said intermediate is the adjustment face that has adopted a truncated cone type, be included in the uncovered flange on every side of cylindrical portion, the twin shaft degree of alignment of the molecule at the flange place of bottom increases gradually from the reducing at top to adjustment member, by flange adjustment member is cut away then, make the flange open-mouth of container have the arrangement of molecule twin shaft, yet, the adjustment member of truncated cone shape is difficult to the degree of molecule twin shaft arrangement and the thickness of flange material are carried out stable control, thereby can't guarantee that the intensity of flange and thickness are enough to make the metal end double seam to engage thereon.

Therefore, the objective of the invention is to overcome existing the problems referred to above in the existing P ET stretch blow-molded large container, a kind of intermediate that is suitable under certain pressure the large container of packing tennis or other article is provided, and they obtain after by PET injection molding preformed part drawn blowing mould.The present invention improves the structure of bottom, makes it can bear internal pressure, and makes its deflection minimum: intensity and the thickness to uncovered circumferential flange improves simultaneously, makes it be enough to bear with double seam joint metal end thereon.The latter is that the adjustment member by the intermediate uniqueness forms.

According to the present invention, the foregoing invention purpose can be by providing a kind of intermediate and finishing with the large container of this intermediate manufacturing, and wherein intermediate is blow-molded by PET injection molding preformed part drawn.

The intermediate of container comprises a cylindrical portion and the lower bottom of molecule twin shaft degree of alignment that molecule twin shaft degree of alignment is higher.The bottom extends out from the lower end of cylindrical portion, and contains the container that can make formation therein and do not press the deformed configurations that produces in pressure-bearing and the control.

The bottom preferably comprises Champagne " type, it contains that the one end extends out from the cylindrical portion lower end, its shape is that radius is the periphery wall in the ball cross section of predetermined value; The bearing ring that one end extends out from the other end of periphery wall, it is that a radius is definite value ring-type is arc; An one end extends out from the bearing ring other end, and it is shaped as the interior pressure-bearing wall of butt right circular cone; At the bottom of being essentially the center arch that non-molecule twin shaft arranges with one, it is that the other end from interior pressure-bearing wall stretches out, radius is the lune of a shere of definite value.

In this bottom construction, there are first and second nodes at the bottom of the center arch and the junction between junction, periphery wall and bearing ring between interior pressure-bearing wall, and these two nodes are to be subjected to downward pressure at the bottom of the center arch at stress raiser that the bottom produced.Since first node outwards, move downward the outside motion with Section Point, the distortion minimum that the bottom produces makes the not pressure-bearing property of volume of a container and bottom that significant change not take place.

Improved flange is radially outwards arranged in the large container cylindrical portion around uncovered, it has higher molecule twin shaft degree of alignment, and its intensity and thickness are enough to bear an end cap, the metal end on particularly double seam engages.This is to assign to realize by the adjustment part that drawn blowing mould in intermediate obtains a uniqueness, and this adjustment member is (its structure illustrates in the back) that the top from cylindrical portion extends out.The flange that the molecule twin shaft is arranged radially outward stretches out from the cylindrical portion upper end, from intermediate production large container process remaining adjustment member is being cut away along ring-type.The step part that molecule twin shaft degree of alignment reduces gradually upwards extends internally around flange, has comprised at least therebetween upwards, inside two continuous step surfaces, so that the amount of PET when concentrating blowing mould, increase that the molecule twin shaft is arranged and the thickness of control flange.

Now, be described in detail in the objects and advantages of the present invention that proposed in the general introduction in conjunction with following accompanying drawing, and other purpose and the advantage that in most preferred embodiment, illustrate.

Fig. 1 is the block diagram with container of structure of the present invention, be included in the container under the certain pressure packing tennis, cover metal end that double seam thereon engages and (among the figure from take away) protective case.

Fig. 2 is the block diagram of the intermediate of pie graph 1 container, and it is made by the stretch blow-molded device.

Fig. 3 is the longitudinal sectional view of injection molding preformed part.This injection molding preformed part is used for stretch blow-molded and becomes intermediate shown in Figure 2.

Fig. 4 is the longitudinal sectional view of a representative type stretch blow-molded device, and the stretch blow-molded intermediate preformed part shown in Figure 3 before that obtains Fig. 2 is housed in the mould.

Fig. 5 is vertical semisectional view of intermediate shown in Figure 2.

Fig. 6 is the top perspective view of container shown in Figure 1, does not comprise metal end among the figure, and has cut away the adjustment member in the intermediate shown in Fig. 2 and 3.

Fig. 7 is the longitudinal sectional view of container shown in Fig. 1,2 and 5 and intermediate bottom.Radius, size and the angle of each arch surface have been indicated on it in detail.

Fig. 8 is the part amplification view of bottom shown in Figure 7;

Fig. 9 is the cutaway drawing of bottom shown in Figure 7, is used for illustrating the thickness of the different arcuate sections in bottom.

Figure 10 is the part sectional view of bottom one side, has shown among the figure for making at the minimum node sketch that is had of certain pressure lower bottom part distortion.

Figure 11 is a view similar to FIG. 10, and it has shown when very little distortion takes place, the cutaway drawing of bottom.

Describe embodiments of the invention in detail referring now to accompanying drawing.Container 10 among Fig. 1 is to be made of the intermediate among Fig. 2 12.Intermediate 12 is seen Fig. 3 by polyethylene terephthalate (PET) injection molding preformed part 13() the stretch blow-molded shaping.In present embodiment and accompanying drawing thereof, container 10 is large containers, and it is suitable for packing tennis (see figure 1) under certain pressure, promptly covers the uncovered of container 10 with metal end 14, and protective case 15 is arranged on the end cap 14.Container 10 of the present invention and intermediate 12 are characterised in that it has improved the structure of bottom 16, make it can bear the interior pressure of container, with Deformation control on the degree of minimum, and the structure (see figure 6) of having improved uncovered circumferential flange 17, make it have enough intensity and thickness, metal end 14 can be adorned thereon according to traditional double seam.As detailed below, this flange is that adjustment member 18(by intermediate 12 uniquenesses sees Fig. 2 and 5) form.

Though present embodiment is described as being used to pack the large container (Fig. 1) of tennis at this with container 10, the distinctive feature of container of the present invention and feature also can be used for the large container of other article of packing under certain pressure.Equally, improved flanged structure 17 also can be used for having in the large container of bottom construction of other type; 16 of improved bottom constructions also are used in the non-large container of connection with wrapping of piece under the pressure.

As mentioned above, the intermediate 12 that constitutes large container 10 is shaped by PET injection molding preformed part 13 stretch blow-molded, this is a general technology, the US Patent of mentioning in front 3, detailed description is arranged: earlier injection molding preformed part 13 is placed on (see figure 4) among the mould M of stretch blow-molded device, uses the mechanical means longitudinal stretching then in 733,309, make its horizontal inflation with high pressure air, reach the shape of intermediate 12.The shape of mould M cavity is to be determined by the three-dimensional shape of required intermediate.Like this, the PET material just is the molecule twin shaft to be arranged, and has obtained intermediate 12.But as described below, the arrangement of this molecule twin shaft can change, particularly at the adjustment member 18 and 16 places, bottom at the top of intermediate product 12.The stretch blow-molded operation is that those of ordinary skills know, and need not to give unnecessary details concerning understanding the present invention.

The PET stretch blow-molded intermediate 12(Fig. 2 and 5 that is shaped) comprise cylindrical portion 20, when stretch blow-molded was shaped, the vertical and horizontal of cylindrical portion PET material stretched and make it have good biaxial molecule arrangement.Intermediate 12 also has adjustment member 18 that cylindrical portion 20 upper ends protrude upward and one by its flange of determining 17.Flange 17 also has good molecule twin shaft to arrange, and it along cylindrical portion 20 upper end open-mouths radially outward obtains remaining adjustment member 18 after ring-type is cut away.Flange 17 fuses with (Fig. 6) cylindrical portion 20 of container 10, is used to accept end cap 14.

Adjustment member 18 comprises step wall, is represented by a, b, c, d, e in Fig. 5.Around flange 17, upwards, locate inwards, the twin shaft degree of alignment of molecule reduces successively along a, b, c, d, e; At least comprised on it upwards, inwards two step a, b, c and c, d, e, step wall part a, b, c, d, e finish at neck 22 places.Neck 22 punishment sons are non-twin shaft arrangement, because it is to be used for preformed part 13 is fixed on (Fig. 4) among the mould M of stretch blow-molded device.Being designed to the step wall adjustment member 18 of this uniqueness, is the thickness of arranging and control flange 17 for the twin shaft that forms molecule at the PET of flange 17 material.Step wall a, b, c, d, e can put together a certain amount of PET when stretch blow-molded, and at this moment unnecessary PET material in a, b, c and c, each rank of d, e are put together.Contained PET quantity of material many than among a, b, the c in c, d, e like this, and the twin shaft degree of alignment of molecule is lower than the latter.The step wall of this uniqueness has two tangible advantages: promptly because the molecule twin shaft degree of alignment difference at step place, thereby make flange 17 have higher molecule twin shaft to arrange; And make the thickness of flange 17 even.Above-mentioned these 2 features have improved and have used the double seam seam, and metal end is installed in ability on the flange 17.

On the contrary, in the container that the existing intermediate that is formed by PET injection molding preformed part stretch blow-molded is made, its adjustment member adopts be constant slope is arranged cone angle (referring to US Patent 4,496,064 and 4,576,843), tapered wall is producing linear expansion (seeing part shown in Fig. 5 dotted line) along b to c to the cross-sectional plane of e, and the sub twin shaft degree of alignment of adjustment member punishment is increased to the flange under it gradually from the neck on top.The variation of the molecule twin shaft degree of alignment by flange, and the variation of thickness of flange makes the intensity of flange and thickness can't satisfy requirement with metal end double seam seam.

The intermediate 12 of container 10 has a lower bottom 16 of improved molecule twin shaft degree of alignment.This bottom is to stretch out along the lower end of cylindrical portion 20.It comprises that not receptor 10 effects and control internal pressure produce deformed configurations (describing in detail in the back).The end 16 is preferably " Champagne " type, and it comprises: the one end extends out from cylindrical portion 20 bottoms, radius is that the periphery wall 25(in the ball cross section of R1 sees Fig. 7); One end extends out from the other end of periphery wall 25, and radius is that the bearing ring 26(of the ring-type bow face of R2 sees Fig. 8), bearing ring is the effect of receptor 10 not; Bottom 16 also has an one end to extend out, be shaped as the just bevelled interior pressure-bearing wall 27 of butt from bearing ring 26 1 ends; Last bottom 16 also has a molecule to be at the bottom of the center arch that non-twin shaft arranges 28, and the other end of this end from interior pressure-bearing wall 27 stretches out, and is that radius is the ball cross section of R3, and it is with the bottom sealing of bottom 16.

The design of above-mentioned bottom 16, be to consider like this on the mechanics: at the bottom of the center arch 28 and the junction of 26 of the junction of interior pressure-bearing wall 27 and periphery wall 25 and bearing rings constitute first and second nodes (in Figure 10 and 11), represent by P1 and P2 respectively, owing to act at the bottom of the center arch 28 downward internal pressures, 16 node place has just produced stress concentration the end of at, first node P1's is outside, move downward outside motion (shown in Figure 10 arrow) with Section Point P2, make the bottom produce certain deformation, promptly be deformed to position shown in Figure 11, and do not make the not pressure-bearing property generation significant change of bottom 16 of the volume or the container 10 of container 10 from the position shown in Figure 10.Node P1 and P2 make bottom variations that bend, and because the distortion of bottom 16 makes the connecting arm angle increase between perpendiculars with it between P1 and P2, and to make the compound radius of periphery wall 25 be underrange no longer (as shown in figure 11).The effect of bearing ring 26 is the not pressure-bearing properties that do not change bottom 16, and this just can know from the comparison of Figure 10 and 11 and find out.

For making its distortion minimum, the size relationship that constitutes bottom 16 is preferably as follows: the maximum dimension D 2 of bottom 16 is greater than the diameter D3 of cylindrical portion 20; The radius R 1 of periphery wall 25 is identical with 28 radius R 3 at the bottom of the center arch; The radius R 2 of bearing ring 26 be at the bottom of the radius R 1 of periphery wall 25 and the center arch 28 radius Rs 34 percent to six.

28 area sums preferably equal the area with the radius R 1 of periphery wall 25 or the radius R 3 cooresponding hemisphere at the bottom of the center arch at the bottom of periphery wall 25, bearing ring 26, interior pressure-bearing wall 27 and the center arch, and the ratio of the maximum dimension D 2 of bottom 16 and the inside diameter D1 of bearing ring 26 is preferably between 1.5 to 1.7.The height H 1 of pressure-bearing wall 27 preferably makes above-mentioned area requirements be met in adjusting, and equals at the bottom of the center arch 28 height H 2.Included angle between interior pressure-bearing wall 27 and container 10 axis is preferably in 7 to 10.

As mentioned above, 28 twin shafts that do not have molecule are basically arranged at the bottom of the center arch, and therefore, its thickness is greater than the thickness of

arcuate section

25,26,27.Can find out also that in Fig. 9 28 thickness increases gradually at the bottom of periphery wall 25, bearing ring 26, interior pressure-bearing wall 27 and the center arch, at the bottom of the center arch 28, the weight of interior pressure-bearing wall 27 and bearing ring 26 accounts for 15% to 20% of container 10 gross weights.

Thus, the intermediate 12 that is formed by PET injection molded stretch blow-molded of large container 10 provided by the invention is suitable for packing tennis or other article under certain pressure, it is characterized in that the structure of bottom 16 is improved, make it can bear internal pressure, and with the degree of Deformation control in minimum, feature of the present invention also comprises the flanged structure 17 around improved uncovered, it is to be formed by the step to a new level adjustment member 18 of shape of intermediate 12, and the intensity of flange and thickness are enough to make metal end through the double seam lid thereon.

Though used some specific terms at above-mentioned accompanying drawing and explanation in the description to most preferred embodiment of the present invention, they are general, descriptive, not special restriction.

Protection scope of the present invention is defined by the claims.

Claims

1, a kind of blow-molded by polyethylene terephthalate injection molding preformed part drawn, be used to be manufactured on the intermediate of the large container of packing article such as tennis under the certain pressure, it is characterized in that being enough to bear an end cap at the intensity and the thickness of uncovered circumferential flange, said intermediate comprises: the very high cylindrical portion of molecule twin shaft degree of alignment, from the outward extending adjustment member in the upper end of this cylindrical portion, it determines a very high flange of molecule twin shaft degree of alignment that radially outward stretches out around the cylindrical portion upper open end, and form this flange after being suitable in the process of making large container by this intermediate cutting away remaining adjustment member along annular, the step part that the molecule twin shaft degree of alignment that upwards extends internally reduces gradually around the flange, which comprises at least upwards, two continuous step surfaces that extend internally, so that when blowing mould, collect the amount of PET, increase the thickness of molecule twin shaft degree of alignment and the above-mentioned flange of control.

2, intermediate as claimed in claim 1, it is characterized in that also comprising that a molecule twin shaft degree of alignment is low, from extended bottom, cylindrical portion lower end, this bottom can make container avoid pressure-bearing, and the distortion that pressure is produced in the control, this bottom constitutes at the bottom of by " Cham-pagne " type, it comprises that an one end extends out from the cylindrical portion lower end, be shaped as the periphery wall in the ball cross section of certain radius, an one end extends out from the above-mentioned periphery wall other end, be shaped as the spherical arc bearing ring of certain radius, an one end extends out from the bearing ring other end, it is shaped as the just bevelled interior pressure-bearing wall in cross section, molecule is non-twin shaft basically arranges, and stretches out from the interior pressure-bearing wall other end, is shaped as at the bottom of the center arch in ball cross section of certain radius.

3, intermediate as claimed in claim 2, the junction of at the bottom of the center arch and the junction of interior pressure-bearing wall and periphery wall and bearing ring wherein, first, second node is arranged, this node is positioned to press to down and acts on the stress raiser that the bottom is produced thereon, first node outwards, move downward the outside motion with Section Point, can control the distortion of bottom, make the non-pressure-bearing property of volume of a container or bottom that significant change not take place.

4, intermediate as claimed in claim 2, wherein Di Bu maximum gauge is greater than the diameter of described cylindrical portion.

5, intermediate as claimed in claim 2, wherein the radius of bottom periphery wall and the radius at bottom centre's arch end are about equally.

6, intermediate as claimed in claim 5, wherein the radius of bottom bearing ring be at the bottom of bottom periphery wall and the center arch radius 4% to 6%.

7, intermediate as claimed in claim 2, wherein the diameter of bottom periphery wall is greater than the diameter of cylindrical portion, the radius that the end is encircleed in radius and the bottom centre of bottom periphery wall about equally, the radius of bottom bearing ring be at the bottom of bottom periphery wall and the center arch radius 4% to 6%.

8, intermediate as claimed in claim 2, wherein the area sum at the bottom of bottom periphery wall, bearing ring, interior pressure-bearing wall and the center arch is substantially equal to the corresponding hemispherical area of periphery wall radius.

9, intermediate as claimed in claim 2, wherein the ratio of bottom maximum gauge and bottom bearing ring inside diameter is between 1.5 to 1.7.

10, intermediate as claimed in claim 2, wherein the height of the interior pressure-bearing wall in bottom and the height at the bottom of the center arch are about equally.

11, intermediate as claimed in claim 2, wherein the longitudinal axis of pressure-bearing wall and this container is 7 to 10 angles of spending in the bottom.

12, intermediate as claimed in claim 2, wherein Di Bu thickness increases at the bottom of center arch successively along periphery wall, bearing ring, pressure-bearing wall.

13, intermediate as claimed in claim 2, at the bottom of the center arch and the junction of interior pressure-bearing wall wherein, and the junction between periphery wall and bearing ring comprises first, Section Point, this node is positioned at the stress raiser that is produced at the bottom of the center arch that acts on by pressing to down thereon, because first node is outside, move downward outside motion with Section Point, can control the distortion of bottom, do not cause the non-pressure-bearing property generation significant change of volume of a container or bottom, the diameter of bottom periphery wall is greater than the diameter of cylindrical portion, the radius at the radius of bottom periphery wall and bottom centre's arch end about equally, the radius of bottom bearing ring be at the bottom of bottom periphery wall and the center arch radius 4% to 6%, the bottom periphery wall, bearing ring, area sum at the bottom of interior pressure-bearing wall and the center arch is substantially equal to the corresponding hemispherical area of periphery wall radius, the maximum gauge of bottom and the ratio of bottom bearing ring inside diameter are between 1.5 to 1.7, the height of pressure-bearing wall and the height at the bottom of the center arch are about equally in the bottom, be 7 to 10 degree angles between the interior pressure-bearing wall of bottom and the longitudinal axis by container, the thickness of bottom is from periphery wall, bearing ring, interior pressure-bearing wall progressive additive at the bottom of the center arch.