Title of Invention

AN INJECTION STRETCH BLOW MOLDED WIDE MOUTHED CONTAINER SUCH AS A PAINT CONTAINER

Abstract An injection stretch blow molded wide mouthed container such as a paint container, comprises : a body portion (2) having a bottom ; a mouth portion (4) having an internal wall (3) integral with the body portion, an external wall (4) of belt shape integral with the internal wall via a joint portion (5) of H-shape, and an upper and lower annular grooves (7, 8) between the walls sectioned by the joint portion ; the body portion being stretch blow molded thinly from the underside of the internal wall (3) to a portion where the lower edge of the external wall (4) touches the body part so that the side surface of the body portion is at the same level as the wall (4) and to form the lower groove (8) into a hollow in the lower part of the mouth portion (1); and ribs (9) provided in the lower groove (8) for preventing deformation of the joint portion in stretching the body portion, each rib being integrally formed aslope onto a corner between the under surface of the joint portion (5) at its external wall side and the inner surface of the external wall (4).
Full Text This invention relates to an injection stretch blow molded wide mouthed container such as a paint container. The present invention in particular relates to a wide mouthed container of synthetic resins for paint, wax and the like, formed thinly in the body portion thereof by injection stretch blow molding.
Description of the Related Art
In a wide mouthed container for paint, wax and the like, a mouth portion thereof comprises an external wall and an internal wall that is formed to be lower than and on the inside of the external wall past an annular groove. A lid is fitted to an inner surface of the mouth portion formed by the internal wall, and a rim of the lid is fitted to the inside of the external wall, so that the container is kept sealed. The lid can be easily removed by inserting the tip of a screwdriver and the like between the external wall and the rim of the lid, and pushing down the screwdriver supported at the external wall.
Conventionally, most of such containers with a double-walled mouth portion are made of metal, but those of synthetic
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resins are newly manufactured by employing the injection
molding method, injection blow molding method and the like.
However, such molded articles cannot be thinly formed in the
body portion thereof, and are poor in strength as compared with
those of metals, which gives rise to a problem in that they are
easily broken when dropped.
Approaches to the problem have been made in which paint
containers and the like are manufactured by employing the
injection stretch blow molding method that enables resins to be
reinforced by biaxial stretching. A paint container disclosed
in WO97/19801 is manufactured by the steps of: injection
molding a preform consisting of a large-diameter mouth portion
comprising an external wall of belt shape and an internal wall
which is formed to be lower than and on the inside of the
external wall via a joint portion past an annular groove, and a
body portion having a bottom which is molded extending from the
underside of the internal wall; conveying the preform to a blow
mold for molding a paint container; and stretch blowing the
preform below the body portion thereof from the underside of
the internal wall.
In the disclosed injection stretch blow molding, the
external and internal walls of the mouth portion cooled and
solidified are held between a mouth forming mold and a core
mold while heated portions below the body portion thereof is
axially stretched. At almost the same time, the body portion is
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also air blown to a skirt portion which is projectingly formed
on the underside of the external wall, so that the unstretched
joint portion and an upside of the body portion which is blown
and stretched into shoulder-shape are integrated.
In a paint container according to the ways described
above, the body portion and bottom, thereof are thin and
biaxially oriented by the stretch blowing. Therefore, as
compared to those manufactured by injection molding or
injection blow molding, such a container is light in weight and
improved in falling strength, and may be improved in gas
barrier capability depending on the material resins.
However, in the stretch blowing according to the
aforesaid prior art, no supporting part for the aforesaid joint
portion is provided between the skirt portion and the internal
wall; therefore, axial tensile stresses concentrate to the
joint portion in stretch blowing, the joint portion is drawn
downwardly from a corner of the skirt portion and deformed, and
strains occur in the internal wall. This gives rise to a
problem in that the molding accuracy is decreased in a mouth
end edge and an inner surface of the internal wall which are to
be a fitting edge and an inner side surface of the mouth
portion, and thus the fit with the lid is deteriorated and the
sealing capability lost.
As the span of the joint portion gets longer, the strains
in the internal wall caused by the axial stretching come to the
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front. This can be improved by reducing the span, which, however, limits the radial expansion of the body portion. The body portion is formed thicker in the upper part and thinner in the lower resulting in unavenness of the wall thickness, which lowers the buckling strength of the body portion. In such cases, containers at the bottom may be deformed by load when a plurality of containers are piled up.
Like an injection blow molded paint container disclosed in the Japanese Patent Laid-Open publication No.Sho 57-77439, ribs may be provided to support the joint portion. However, such ribs as described therein being formed across the external and internal walls cause a difference between ribbed and non-ribbed portions in stretched state. As a result, irregularity tends to be induced on the inner surface of the internal wall to which a lid is fitted.
Since touching to and located between the external and internal walls, the ribs take time to be cooled and solidified completely enough for bearing the tensile stress. On the other hand, the preform has to be released from the molds while the portions below the body portion still have a required amount of heat for stretch blowing. Therefore, the support by providing
the ribs has not always been an effective approach for
injection stretch blow molding.
Through the perpetual studies of the inventor of the
present invention concerning the prevention of the aforesaid
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tensile deformation of the internal wall caused by the axial stretch, it was found that even though ribs ate employed for supporting; the joint portion, conventional defects can be avoided depending on the way of forming ribs. That is, even in a wide mouthed container such as an injection stretch blow molded paint container, it is possible to prevent the deformation of the joint portion resulting from, the stretching, as well as to avoid the convexo-concave deformation of the inner surface of the mouth portion caused by the conventional ribs and to finish the cooling and solidification of the ribs in a short time.
SUMMARY OF THE INVENTION
It is thus an object of the present invention to provide an injection stretch blow molded wide mouthed container of large diameter for a paint container and the like in which the problem of the strains in the internal wall resulting from the tensile deformation of the aforesaid joint portion is solved by the introduction of the reinforcing means using small ribs, and, despite of being made of synthetic resins, the body portion is formed thinly and is improved in falling strength because of the biaxial orientation.
In addition, the present invention is to provide an injection stretch blow molded wide mouthed container of large
diameter for a paint container and the like in which the body
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portion and the external wall of the mouth portion are formed into side faces on the same level, like conventional paint tins and the like. By this means, even if the radial expansion of the body portion is limited, the employing of a preform of certain shape in cross-section allows the body portion to be molded without non-uniform wall thickness, thereby enabling a plurality of the wide mouthed containers to be piled up.
Furthermore, the present invention is to provide an injection stretch blow molded wide mouthed container of large diameter for a paint container and the like in which a handle can be rotatably mounted across both sides of the mouth portion by utilizing the external wall, and the lid can be prevented from popping-out caused by a reaction in removing the lid, an increase in pressure inside the container, or the like.
Accordingly, the present invention provides an injection stretch blow molded wide mouthed container such as a paint container, comprising :
a body portion having a bottom ;
a mouth portion of large diameter comprising an internal wall integral with the body portion, an externa! wall of belt shape integrally formed on the outside of the interna! wall via a joint portion of required width to be in H-shape, and an upper and lower annular grooves between both the walls sectioned by said joint portion ;
said body portion being stretch blow molded thinly from the underside of the internal wall to a position where the lower edge of the external wall touches the body portion to form the side surface of the body portion on the same level as said external wall and to form the lower annular groove into a hollow in the lower part of the mouth portion ; and
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a plurality of ribs for preventing the deformation of the joint portion in stretching the body portion, each said rib being integrally formed aslope onto a corner between the under surface of said joint portion at its external wall side and the inner surface of the external wall, a required number of the ribs being provided in the lower annular groove at a regular interval.
In such a configuration, even if axial tensile forces concentrate to the joint portion in stretch blowing, the joint portion holds so as to prevent the internal wall from being distorted downwardly by the tensile forces since the joint portion is supported by the aforesaid ribs at a regular interval. Therefore, the end edge of the internal wall suffers from no deformation, and keeps the same horizontal accuracy as in the injection molding. The ribs are located on the externa! wall side apart from the internal wall, which solves the problem that the existence of a rib causes a difference in stretched state of the interna! wall and an irregularity occurs on the side surface of the internal wall to which a lid is fitted. In addition, the ribs are rapidly cooled and solidified along with the external wall, so that the mouth portion with the ribs will not take a long time to be cooled.
In addition, the present invention is provided in which
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the container is molded, in such a manner that an injection molded preform comprising a mouth portion of large diameter composed, of an internal wall integral with a body portion having a bottom, an external wall of belt shape integrally formed on the outside of the internal wall via a joint portion of required width to be in H-shape, and an upper and lower annular grooves between both the walls sectioned by the aforesaid joint portion, is held at the aforesaid mouth portion provided by cooling and solidifying the aforesaid body portion, and is stretch blown to the same level as the aforesaid external wall while a portion from the underside of the aforesaid internal wall to the body portion is in high temperatures.
The aforesaid preform comprises the body portion extending from the aforesaid internal wall in which the body portion is composed of a thick-walled planiform stretch expanded portion of corn shape and a recess of required diameter formed at the center of the aforesaid preform by outwardly projecting a top portion of the stretch expanded portion, the bottom surface of the recess is formed to be nearly flat and thin, and the stretch expanded portion on the periphery of the recess is formed to curve inwardly.
In the preform, a top portion of a stretch rod is set into the aforesaid recess and expanded to press the bottom,, so
that the stretch expanded portion in heated state is stretched
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from a hem of the internal wall to be thinned. Therefore, a
wide mouthed container with generally uniform thickness in the body portion can be obtained although the radial, expansion of
the body portion is. limited to the position of the external
wall.
The present invention is also provided in which mounting holes are formed at symmetrical positions on the external wall in the molding of the aforesaid preform, and fitting tabs projectingly provided on the inner sides of both end portions of a flexible corded handle are rotatably fitted and locked into the mounting holes respectively to mount the aforesaid handle across both sides of an opening portion. Here, the aforesaid fitting tabs axe of tablet shape and comprise a semicircular locking block on the upside of the tip thereof, and the end portions of the handle and the fitting tabs comprise a slit extending from the lower end to the central portion thereof. The slits allow the end portions of the handle and the fitting tabs to be reduced in size to insert the fitting tabs along with the locking blocks into the aforesaid mounting holes rotatably, so that the aforesaid locking blocks are hooked and set inside the external wall.
Moreover, the present invention is provided in which a projection for latching is projectingly provided on a rim of a lid and is inserted into a fitting hole provided in a side
surface of the external wall to close the lid, thereby
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preventing the lid from popping-out caused by a reaction in opening.
Furthermore, the present invention is provided in which a rim of a lid of synthetic resins is formed largely in diameter to extend over a mouth end edge of the external wall and is shaped into a fitting groove so that the lid can be fitted both to the inner surface of the interna! wall and to the mouth end edge of the externa! wall, an engaging edge is formed on the outside of the mouth end edge of the external wall, and a secondary fitting provided between the engaging edge and an annular groove formed in the inside of the aforesaid fitting groove prevents the lid from self-opening resulting from a looseness of the fitting with the inner surface of the mouth portion caused by the internal, pressure of the paint container. Here, an air vent is also provided in the aforesaid external wall for discharging the gas leaked out on account of the loosened fit of the aforesaid lid with the inner surface of the mouth portion so as to reduce the content of the paint container, so that the sealing resulting from the fit with the inner surface of the mouth portion is restored.
BRIEF EXPLANATION OF THE ACCOMPANYING DRAWINGS
In the accompanying drawings,
Fig. 1 is a longitudinal sectional view of a stretch blow molded wide mouthed container according to the present invention;
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Fig- 2 is an enlarged sectional view of a stretch blow
molded wide mouthed container according to the present
invention;
Fig". 3 is a longitudinal sectional view of a preform of a
stretch blow molded wide mouthed container according to the
present invention;
Fig. 4 is a bottom plan view of the preform;
Fig. 5 is a sectional view of a preform of a stretch blow
molded wide mouthed container according to the present
invention in molding a paint container, where dashed lines show
the preform under the stretch blowings. Fig. 6 is an enlarged partially sectional view of a mouth
portion of a stretch blow molded wide mouthed container
according to the present invention;
Fig. 7 is a front view of a paint container with a handle
according to the present invention, where dashed lines show the
piled state thereof;
Fig. 8 is a side view of a paint container with a handle
according to the present invention;
Fig. 9 is a partially cutaway plan view of a paint
container with a handle according to the present inventions; Fig. 10 is a partially longitudinal sectional view of a mouth portion showing the mounting state of a handle and the
fitting state of a lid at its rim; and
Fig, 11 is a partially longitudinal sectional view of a
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mouth portion with a lid having fitting means to a mouth end. edge of an external wall.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A wide mouthed container shown in Fig. 1 is a paint container molded of polyethylene terephthalate (PET) . A large-diameter mouth portion 1 comprises an internal wall 3 integral with a body portion 2 having a bottom, an external wall 4 of belt shape integrally formed on the outside of the internal wall 3 via a joint portion 5 of required width to be in H-shape, and an upper and a lower annular groove 7 and 8 between both the walls 3 and 4 sectioned by the joint portion 5. The external; wall 4 is formed taller than the internal wall 3. A projection 6 is integrally molded on the outside of" an end edge of the external wall 4.
The aforesaid body portion 2 is stretch blow molded thinly (about 0.5 mm) and vertically from the underside of the internal wall 3 to a portion where the side surface of the body portion 2 reaches to and becomes at the same level as the external wall 4. By this means, the lower annular groove 8 is formed into a hollow in the underside of the mouth portion 1, a pedestal 11 of a diameter smaller to some extent than the internal wall 3 is projectingly molded on a bottom portion 10 extending from the body portion 2, and thus the wide mouthed
paint container is formed.
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Designated by 9 are ribs for supporting the joint portion
5, eight of which are provided in the aforesaid lower annular
groove 8 at a regular interval in this embodiment. The ribs 9
are integrally formed aslope on corners between the under
surface of the joint portion 5 on the external wall side and
the inner surface of the external wall 4, apart from the
internal wall 3, so as to prevent the deformation of the joint
portion 5 in stretching the body portion.
In a paint container of such configuration, as shown in
Fig. 2, a lid 30 is fitted into the inside of the internal wall
3 like well-known paint tins, and a rim 30a of the lid 30 is
received by a mouth end edge 3a of the internal wall 3, so that
the lid 30 is set inside the external wall 4-
Fig. 3 shows a preform 12 of the aforesaid paint
container. The mouth portion 1 of the paint container is
injection molded in advance as a mouth portion 13 of the
preform 12 of the same structure along with a bottomed body
portion of the preform 12 extending from the internal wall 3 .
The body portion of the preform is composed of a thick-walled
planiform stretch expanded portion 14 of corn shape, and a
recess 16 of required diameter formed at the center of the
preform by projecting a top portion 15 of the stretch expanded
portion outwardly- The recess 16 is formed to be thin and
nearly flat at its bottom surface 17 , and to curve inwardly at
its stretch expanded portion 14a (see Figs. 4 and 5) on the
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periphery of the recess 16.
The preform 12 is released from an injection mold while portions from the underside of the internal wall 3 to the stretch expanded portion 14 are still in heated state. Dp to this time, the mouth portion 13 of the preform is cooled and solidified. Accordingly, as shown in Fig. 5, with the mouth portion 13 held at its outside with a mouth forming mold 18 used in the injection molding, the preform is conveyed to a blow mold 19 before a blow core 20 is fitted to the internal wall 3. Here, with the previously solidified mouth portion 13 of the preform held between the blow core 20 and the mouth forming mold 18 , the preform is stretch blow molded into a wide mouthed container.
The stretch blow molding is performed in such a manner that: a top portion 22 of a stretch rod 21 equipped in the blow core 20 is set into the recess 16; the center portion of the preform is pressed downwardly with the stretch rod 21 so as to extend the body portion of the preform axially from the underside of the internal wall 3; and, almost at the same time, the stretch expanded portion 14 is expanded radially by air blowing.
In the preform 12, an upper part of the stretch expanded portion 14 is stretched to be slightly thinner by the expansion of the aforesaid stretch rod 21- The thinning of the wall
lowers the temperature of the part, so that the stretch is
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shifted to an unstretched portion below. After this manner, the expanded portion 14a on the periphery of the recess 16 curving inward is stretched, and the body portion of the preform is changing into an elongated truncated corn shape. Here, the distance of the body portion of the preform from a cavity surface of the blow mold 19 increases as approaching to the bottom, which makes a difference in radial stretch ratio at the upper and lower parts. However, the difference is cancelled to some extent by the wall thickness, so that the body portion 2 of the paint container is prevented from the unevenness in wall thickness.
Accordingly, even in a paint container that tends to be limited in radial stretch expansion more tightly and formed thicker in uppet parts, the body portion 2 expanded and formed thinly from the internal wall 3 to a portion where to meet with the under edge of the external wall 4 ±s evened in wall thickness distribution and improved in buckling strength.
The stretch blow molding may be favorably performed before the surface temperature of the stretch expanded portion 14 in heated state is fully heated up to its peak temperature by the internal heat.
Moreover, in the axial stretch by the stretch rod 21, the
mouth portion 13 of the preform is previously solidified and is
held between the mouth forming mold 18 and the blow core 20. On
the other hand, the internal wall 3 is held only at one side
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against the blow core 20, merely by flat contact, differing from the external wall 4 which is held by the fitting of a projecting edge 6 Therefore, the downward tensile force causes a slip in the internal wall 3, resulting in the concentration of stresses to the aforesaid joint portion 5.
However, the tensile stresses are partially dispersed to the external wall 4 via the aforesaid ribs 9 formed on the corners" between' the joint portion 5 and the external wall 4. The ribs 9 also enable the joint portion 5 to resist against the tensile force. As a result, the strain in the internal wall
3 caused by the joint portion 5 is deterred, the inner surface
of the mouth portion formed of the internal wall 3 and the
mouth end edge 3a of the stretch blow molded paint container
are prevented from deformation, and the shape and the *
horizontal accuracy are kept assured as in the previous
injection molding,.
Furthermore, being provided in the lower annular groove 8, the ribs 9 for preventing the deformation differ from well-known ribs formed across the internal and external walls 3 and
4 in that they are easily cooled along with the external wall 4
because of being isolated from the internal wall 3. In addition,
the ribs cause no irregular deformation of the inner surface
since they are not in touch with the internal wall 3.
Moreover, the lower annular groove 8 of the joint portion
5 is left closed with the blow molded body portion 2 to form a
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hollow after the molding. The aforesaid ribs 9 in the hollow.
reinforce the external wall 4 against external force, so that
the strain in the external wall 4 is deterred, and the mouth
portion 1 is also prevented from the deformation by the
external force.
Accordingly, even though the wide mouthed container is of
stretch blow molded synthetic resins, no disorder occurs in
molding accuracy of the injection molded mouth portion, so that
a lid is freely fitted and a poor sealing hardly occurs. In
addition, the biaxial orientation of the body portion improves
the impact strength and the gas barrier capability, thereby
enhancing its use for a wide mouthed container for a paint and
the like in which the color of the content is distinguishable
from the outside. Furthermore, wide mouthed containers of the
same configuration can be manufactured from various synthetic
resins as long as the resins are available for stretch blow
molding, and thus be widely applied to wide mouthed containers
for volatile content.
Figs. 7 to 10 show a case where a handle 23 is mounted to
a paint container by utilizing the aforesaid external wall 4
In molding the aforesaid preform 12 mounting holes 24 are
formed at symmetrical positions on the external wall 4 by using
projecting portions (not shown) provided in the mouth forming
mold 18 of split molds. Fitting tabs 25 projectingly provided
on the inner sides of both end portions of the corded handle 2 3
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of flexible synthetic resins (polypropylene, for example) are rotatably fitted and locked into the mounting holes 24, respectively.
The aforesaid fitting tabs 25 are of tablet shape and have a semicircular locking block 26 on the upside of their tips, respectively. The end portions of the handle and the fitting tabs 25 have a slit 27 extendingr from their lower end to the center. The slits 27 enable the fitting tabs 25 along with the end portions of the handle to be pressed and reduced in size so that the locking blocks 26 can be upwardly slantly inserted into the mounting holes 24. In this manner, the locking blocks 26 are set in the aforesaid lower annular groove 8 forming a hollow, and are retained inside the external wall 4 Note that provided concavely in the peripheral surface of the external wall 4 is a retention groove 28 for use in the stretch
blowing.
The bottom of the paint container may be formed into a step portion 2a in the periphery thereof, as shown in Fig. 7, in stead of the aforesaid pedestal 11- Here, the step portion 2a is provided with an outer diameter smaller to some extent than the inner diameter of the external wall 4 so as to be set inside the external wall 4, and a bottom periphery 2b is provided with a proper height so as to ride on the mouth end edge of the external wall 4. By this means, when a plurality of
the paint containers are piled up as shown in Fig. 7,
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respective loads thereof hold down the lids 30 of the paint containers below. Furthermore, even if the loads cause the distortion in the body portions, the external walls 4 can provide a support against falling down.
In Fig. 10, a projection 30b for locking is projectingly provided on a rim 30a of the aforesaid lid 30 of synthetic resins, and a fitting hole 29 for fitting the projection 30b is provided in the side surface of the external wall 4. The lid 30 is closed with the projection 30b inserted into the fitting hole 29, and is opened by being unclenched at the opposite side to the projection 30b'. This prevents the lid 30 from popping-out caused by a reaction in opening.
In such a configuration, the external wall 4 is molded higher than the internal wall 3 by the width of the fitting hole 29, and the lid cannot be opened with a screwdriver and the like by using the mouth end edge of the external wall 4 as the fulcrum. Therefore, a notch 31 for lid opening is formed in the edge opposite the fitting hole 29, as shown in Fig 9 The notch 31 is not limited to the aforementioned position, and a plurality thereof may be provided.
In Fig. 11, the lid 30 of synthetic resins is provide in
which the rim 30a thereof is formed largely in diameter to
extend over a mouth end edge of the external wall 4 and is
shaped into a fitting groove 30c so that the lid can be fitted
both to the inner surface of the internal wall 3 and to the
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mouth end edge of the external wall 4. An engaging edge 32 is
formed on the outside of the mouth end edge of the external
wall 4. In at case where an evaporated solvent resulting from
hot air and the like causes a rise in the internal pressure of
the paint container and loosens the fit of the lid to the inner
surface of the mouth portion, the lid 30 may open by itself.
However, a fit between the rim 30a and the mouth end edge of
the external wall 4 utilizing a secondary fit provided between
the aforesaid engaging edge 32 and an annular 30d groove formed
in the inside of said fitting groove 30c prevents the lid 30
from opening and popping-out.
In addition an air vent 33 is provided in the external
wall 4 so that, when an increase in the internal pressure
loosens the fit with the inner surface of the mouth portion and
causes the evaporated gas to leak out, the air vent 33
discharges the gas and reduces the internal pressure to restore
the seal resulting from the fit with the inner surface of the
mouth portion.
As described above, in an injection stretch blow molded
wide mouthed container of large diameter for a paint container and the like according to the present invention, a solution to
the strains and the like in the internal wall resulting from
the tensile deformation of the aforesaid joint portion is
provided by the introduction of the reinforcing means using
small ribs. In addition, the body portion is formed thinly and
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is improved in falling strength because of the biaxial
orientation.
Moreover, in the vide mouthed container according to the
present invention, the employing of a preform of certain, shape
in cross-section enables the body portion to be molded without
irregular in wall thickness, and thereby enabling a plurality
of the wide mouthed containers to be piled up.
Furthermore, in the wide mouthed container according to
the present invention, a handle can be rotatably mounted across both sides of the mouth portion by utilizing the external portion. Besides, the lid can be prevented from popping-out caused by a reaction in removing the lid, an increase in pressure inside the container or the like.
While there has been described what are at present considered to be preferred embodiments of the invention, it will be understood that various modifications may be made thereto, and it is intended that the appended claims cover all such modification as fall within the true spirit and scope of the invention.
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WE CLAIM:
1. An injection stretch blow molded wide mouthed container such as a paint
container, comprising :
a body portion having a bottom ;
a mouth portion of large diameter comprising an internal wall integral with the body portion, an external wall of belt shape integrally formed on the outside of the internal wall via a joint portion of required width to be in H-shape, and an upper and lower annular grooves between both the walls sectioned by said joint portion ;
said body portion being stretch blow molded thinly from the underside of the internal wall to a position where the lower edge of the external wall touches the body portion to form the side surface of the body portion on the same level as said external wall and to form the lower annular groove into a hollow in the lower part of the mouth portion ; and
a plurality of ribs for preventing the deformation of the joint portion in stretching the body portion, each said rib being integrally formed aslope onto a corner between the under surface of said joint portion at its externa! wall side and the inner surface of the external wall, a required number of the ribs being provided in the lower annular groove at a regular interval.
2. An injection stretch blow molded wide mouthed container such as a paint
container as claimed in claim 1, wherein an injection molded preform comprising a
mouth portion of large diameter composed of an internal wall integral with a body
22

portion having a bottom, an external wall of belt shape integrally formed on the outside of the interna! wa!! via a joint portion of required width to be in H-shape, and an upper and lower annular grooves between both the walls sectioned by said joint portion, is attached at said mouth portion by cooling and solidifying said body portion, and is stretch blown to the same level as said external wall while a portion from the underside of said internal wall to the body portion is at high temperatures.
3. An injection stretch blow molded wide mouthed container such as a paint container as claimed in claim 2, wherein said preform comprising the body portion extends from said interna! wall, the body portion comprising a thick-walled planiform stretch expanded portion of corn shape and a recess of required diameter formed at the center of said preform by outwardly projecting a top portion of the stretch expanded portion; the bottom surface of the recess being formed to be nearly flat and thin ; and the stretch expanded portion on the periphery of the recess being formed to curve inwardly.
4. An injection stretch blow molded wide mouthed container such as a paint container as claimed in claim 1, wherein mounting holes are formed at symmetrical positions on the external wall in the molding of said preform; and fitting tabs projectingly provided on the inner sides of both end portions of a flexible corded handle are rotatably fitted and locked into the mounting holes respectively to mount said handle across both sides of an opening portion.
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5. An injection stretch blow molded wide mouthed container such as a paint container as claimed in claim 4, wherein said fitting tab is of tablet shape and has a semicircular locking block on the upside of the tip thereof; the end portions of the handle and the fitting tabs are provided with slits extending from the lower end to the centra! portion thereof, the slits permitting the end portions of the handle and the fitting tabs to be reduced in size to insert the fitting tabs along with the locking blocks into said mounting holes rotatably, so that said locking blocks are hooked and set inside the external wall.
6. An injection stretch blow molded wide mouthed container such as a paint container as claimed in claim 1, said container comprising a lid, wherein a projection for latching is projectingly provided on a rim of the lid, and is inserted into a fitting hole provided in a side surface of the external wall to close the lid, thereby preventing the lid from popping-out caused by a reaction in opening.
7. An injection stretch blow molded wide mouthed container such as a paint container as claimed in claim 1, wherein a rim of a lid of synthetic resins, large in diameter, extends over a mouth end edge of the externa! wall and is shaped into a fitting groove so that the lid can be fitted both to the inner surface of the internal wall and to the mouth end edge of the external wall; an engaging edge is formed on the outside of the mouth end edge of the external wall; and a secondary fit is provided between the engaging edge and an annular groove formed in the inside of said fitting
24

groove to prevent the lid from self-opening resulting from a looseness of the fitting with the inner surface of the mouth portion caused by the interna! pressure of the container
25
8. An injection stretch blow molded wide mouthed container such as a paint container as claimed in claim 7, wherein an air vent is provided in said external wall for discharging the gas leaked out on account of the loosened fit of said lid with the inner surface of the mouth portion so as to reduce the content of the paint container so that the sealing resulting from the fit with the inner surface of the mouth portion is restored
9. An injection stretch blow molded wide mouthed container such as a paint container, substantially as herein described, particularly with reference to the accompanying drawings.
An injection stretch blow molded wide mouthed container such as a paint container, comprises :
a body portion (2) having a bottom ;
a mouth portion (4) having an internal wall (3) integral with the body portion, an external wall (4) of belt shape integral with the internal wall via a joint portion (5) of H-shape, and an upper and lower annular grooves (7, 8) between the walls sectioned by the joint portion ; the body portion being stretch blow molded thinly from the underside of the internal wall (3) to a portion where the lower edge of the external wall (4) touches the body part so that the side surface of the body portion is at the same level as the wall (4) and to form the lower groove (8) into a hollow in the lower part of the mouth portion (1); and
ribs (9) provided in the lower groove (8) for preventing deformation of the joint portion in stretching the body portion, each rib being integrally formed aslope onto a corner between the under surface of the joint portion (5) at its external wall side and the inner surface of the external wall (4).

Documents:

02092-cal-1998-abstract.pdf

02092-cal-1998-claims.pdf

02092-cal-1998-correspondence.pdf

02092-cal-1998-description(complete).pdf

02092-cal-1998-drawings.pdf

02092-cal-1998-form-1.pdf

02092-cal-1998-form-18.pdf

02092-cal-1998-form-2.pdf

02092-cal-1998-form-3.pdf

02092-cal-1998-form-5.pdf

02092-cal-1998-g.p.a.pdf

02092-cal-1998-letters patent.pdf

02092-cal-1998-priority document others.pdf

02092-cal-1998-priority document.pdf

2092-cal-1998-granted-abstract.pdf

2092-cal-1998-granted-claims.pdf

2092-cal-1998-granted-description (complete).pdf

2092-cal-1998-granted-drawings.pdf

2092-cal-1998-granted-form 2.pdf

2092-cal-1998-granted-specification.pdf

2092-cal-1998-priority document.pdf

2092-cal-1998-translated copy of priority document.pdf


Patent Number 201394
Indian Patent Application Number 2092/CAL/1998
PG Journal Number 07/2007
Publication Date 16-Feb-2007
Grant Date 16-Feb-2007
Date of Filing 27-Nov-1998
Name of Patentee A. K. TECHNICAL LABORATORY, INC.
Applicant Address 4963-3, OHAZAMINAMIJO, SAKAKIMACHI, HANISHINA-GUN, NAGANO-KEN
Inventors:
# Inventor's Name Inventor's Address
1 HIDEAKI KODA C/O A. K. TECHNICAL LABORATORY, INC. 4963-3, OHAZAMINAMIJO, SAKAKIMACHI, HANISHINA-GUN, NAGANO-KEN
PCT International Classification Number B29C 51/02
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 9-329070 1997-11-28 Japan
2 9-329071 1997-11-28 Japan