BACKGROUND OF THE INVENTION
[0001] This invention relates to a relatively large synthetic resin bottle-shaped container.
[0002] Biaxially oriented blow-molded bottle-shaped containers made of acrylonitrile resin
or polyethylene terephthalate resin are popularly used because of their mechanical
strength, transparency and other excellent properties.
[0003] Such biaxially oriented blow-molded bottle-shaped containers are generally divided
into two groups: those having a semispherically bulged bottom for an enhanced internal
pressure resistivity and provided with a base cup that serves as a stand and those
having a bottom with an internally depressed central area that serves as a stand for
self-standing without a base cup.
[0004] A bottle-shaped body having a self-standing capability is advantageous over a bottle-shaped
body provided with a base cup in terms of easy cleaning, sterilization, molding and
assembling as well as of overall appearance.
[0005] However, a self-standing bottle-shaped body has only a small bottom area that supports
the bottle-shaped body relative to the cross sectional area of a body portion and
therefore is less stable when it stands by itself.
[0006] More specifically, when a circular peripheral portion of the bottom that serves as
a stand for the bottle-shaped body is formed by depressing the central area of the
bottom by blow-molding, the circular peripheral portion of the bottom is inevitably
located nearer to the center of the bottom than the outer circumference of the body
portion. This fact results in the reduced bottom area that supports the bottle-shaped
body in an upright condition.
[0007] Moreover, when a high internal pressure is applied to such a self-standing bottle-shaped
body, the bottom portion forming a stand is subjected to a relatively large expansion,
which in turn adversely affects the self-standing capability of the bottle-shaped
body to a significant extent. Such an expansion can results in an deformation.
[0008] On the other hand, in a bottle-shaped body provided with a base cup for keeping it
upright, the height of the base cup is required to be of a relatively large in order
to accommodate the outwardly projecting semispherical bottom portion of the bottle-shaped
body so that the overall appearance of the bottle-shaped container will be aesthetically
poor because of the disproportional large base cup. Moreover, the bottom of such a
bottle-shaped body can not protect expansion and deformation when a large internal
pressure is applied thereto.
[0009] Besides, a biaxially oriented blow-molded bottle-shaped container made of acrylonitrile
resin is insufficiently resistive to shocks applied to the bottom and can produce
cracks and fissures on the bottom when it is inadvertently dropped.
SUMMARY OF THE INVENTION
[0010] In view of the above described problems, it is therefore the object of the present
invention to provide a bottle-shaped container having a depressed area at the center
of the bottom for providing with a pedestal as self-standing means wherein said bottom
has an enhanced and stable self-standing capability and protects any expansion and
deformation and at the same time has highly resistive to shocks.
[0011] According to the invention, the above object is achieved by providing a synthetic
resin bottle-shaped container comprising a biaxially-oriented blow-molded bottle-shaped
body having a relatively long press-fit recess on a curved outer peripheral surface
area of a curved bottom portion and a cylindrical pedestal body having a straight
and cylindrical upper half portion with an outer diameter substantially equal to that
of a body portion of said bottle-shaped container, said upper portion being so configured
as to be closely engaged with said press-fit recess at its curved inner peripheral
surface, said cylindrical pedestal body further having a hollow pedestal-shaped lower
half portion for accommodating the bottom of said bottle-shaped body portion so that
the lowest end of the lower half portion of said pedestal body is positioned below
the lowest end of the bottom portion of the body portion.
[0012] Said press-fit recess formed on the curved peripheral surface area of the bottle-shaped
body is preferably so formed that the recess is progressively deeper toward the lower
end thereof.
[0013] Since the press-fit recess is formed in progressively deeper toward the lower end
thereof on the curved outer peripheral surface area of the bottom portion, and the
matching curved inner surface area which is formed on the inner peripheral surface
of the upper half portion of the cylindrical pedestal body is tapered toward the upper
end thereof. Therefore, the bottom of the bottle-shaped body is closely engaged with
the pedestal body by simply pressing downward the bottle-shaped body until said curved
outer peripheral surface area of the bottom of the bottle-shaped body is completely
in contact with the matching curved inner peripheral surface area of the cylindrical
upper half portion of the pedestal body.
[0014] When said press-fit recess formed on the curved outer peripheral surface area of
the bottle-shaped body is so configured that the recess is progressively deeper toward
the lower end thereof and a relatively high projecting portion is provided at the
lower end of the press-fit recess, a press-fit rib projecting at the lower end of
the curved inner peripheral area of the cylindrical upper half portion of the pedestal
body is closely engaged with the high projecting portion to produce a firm and stable
engagement between the bottle-shaped body and the pedestal body.
[0015] With such an arrangement, since the curved outer peripheral surface of the bottom
of the bottle-shaped body is closely engaged with the inner surface of the pedestal
body, an enhanced inner pressure is supported by the inner surface of the pedestal
body, and the bottom of the bottle-shaped body is protected against any undesirable
expansion and deformation due to such an enhanced inner pressure.
[0016] Besides, since the lowest end of the lower half portion of the pedestal body is always
positioned below the lower end of the bottom of the bottle-shaped body, the lower
end surface of pedestal body provides a firm and stable support for the bottle-shaped
body regardless of expansion and deformation of its bottom.
[0017] Moreover, since the pedestal body is not integral with the bottle-shaped body and
the pedestal body serves as a shock absorber that effectively protects the bottom
of the bottle-shaped body from cracks and fissures, the bottom of the bottle-shaped
body has sufficiently high sensitivity to any shocks even if the bottle-shaped container
is made of acrylonitrile resin and it is dropped from a high position.
[0018] Now the present invention will be described in greater detail by referring to the
accompanying drawings that illustrate a preferred embodiment of the invention.
BRIEF EXPLANATION OF THE DRAWINGS
[0019] Fig. 1 is a front view of the embodiment showing the pedestal body in partial longitudinal
cross section.
[0020] Fig. 2 is an enlarged longitudinal sectional view showing only the encircled area
in Fig. 1.
PREFERRED EMBODIMENT
[0021] In Figs. 1 and 2, reference numeral 1 denotes a biaxially-oriented blow-molded bottle-shaped
body portion made of synthetic resin and a bottom portion 3 is integrally formed at
the lower end of the body portion 2 of the bottle portion 1. The bottom section 3
has a depressed area 6 at the center thereof and a peripheral projecting area surrounding
said depressed area can serve as a stand or support structure in a conventional hollow
bottle-shaped body of the self-standing type.
[0022] Now referring to Fig. 2, a relatively long press-fit recess 4 is formed on the outer
peripheral surface area of the curved surface of the bottom portion 3 near the body
portion 2 and the recess 4 is so configured that its depth is progressively increased
as it approaches the lower end thereof. Therefore, a relatively high projecting portion
5 is formed at the lower end of the press-fit recess 4.
[0023] On the other hand, a pedestal body 7 for supporting the bottle-shaped body 1 is formed
as a whole in the form of a short and straight cylinder and an upper half cylindrical
portion 9 of the pedestal body 7 is provided with a curved inner surface area 10 matching
the outer peripheral surface area of the press-fit recess 4. Since the both curved
surfaces have a same radius of curvature, they are closely engaged with each other
in a press-fit manner when assembled. A press-fit rib 11 is projected at the lower
end of said curved inner surface area 10 of the upper half cylindrical portion 9 of
the pedestal body and is closely engaged with the lower edge of the press-fit recess
4 when assembled.
[0024] With such an arrangement, since a step is formed at the boundary between the press-fit
cylindrical upper half portion 9 and the lower half pedestal portion 8 of the pedestal
body 7, the projecting portion 5 does not constitute any obstacle when the bottle-shaped
body 1 and the pedestal body 7 are assembled.
[0025] Said press-fit rib 11 is so sectionally constructed in a sharp top shape that it
can be resiliently deformed. While, the curved inner surface area 10 is so tapered
toward the upper end thereof that it provides a guide surface for properly engaging
the bottle-shaped body 1 with the pedestal body 7. The press-fit rib 11 can be resiliently
deformed and easily pass over the projecting portion 5 for engagement of the bottle-shaped
body 1 and the pedestal body 7 when they are assembled together.
[0026] Because of the engagement between the rib 11 and the projecting portion 5, the pedestal
body 7 is strongly fitted to the bottom portion 3 of the bottle-shaped body 1 once
they are assembled.
[0027] Said pedestal body 7 is made of a synthetic resin material which is highly resistive
against shocks and therefore can provide satisfactory protection for the bottle-shaped
body 1 against external shocks even when the bottom portion 3 of the bottle-shaped
body 1 is made of acrylonitrile resin.
[0028] Because of the construction described above, the present invention provides the following
advantages.
[0029] Firstly, since the pedestal body is formed in the form of a short and straight cylinder
having an outer diameter substantially identical with that of the body portion of
the bottle-shaped container, the flat bottom surface of the lower end of the pedestal
body provides the stable support for the bottle-shaped body in its upright position.
[0030] Secondly, since the overall height of the pedestal body is only slightly greater
than that of the bottom portion having a depression at the center thereof, the pedestal
body has a sufficiently reduced height relative to that of the elongated bottle-shaped
main body. Consequently, the pedestal body does not provide poor impression of the
container in appearance.
[0031] Thirdly, since the pedestal body is tightly press fitted to the outer peripheral
area of the bottom portion of the bottle-shaped body, it can effectively prevent any
expansion and deformation of the bottom portion occurring due to an enhanced internal
pressure. Consequently, the resistance against the inner pressure of the bottle-shaped
body having a depressed central area at the bottom portion can be considerably increased.
[0032] Additionally, since the bottle-shaped body is closely engaged with the pedestal body
by a simple press-fit operation, the two bodies can be assembled without any difficulty.
Moreover, since the two bodies are conveniently and mutually guided to a proper position,
they can be accurately assembled.
[0033] Finally, since the pedestal body is made of a highly shock-absorbing synthetic resin
material, it can effectively protect the bottom portion of the bottle-shaped body
from external impacts, and prevent the bottle-shaped body from damages when the container
is dropped even if the container is made of a material having a relatively poor shock
resistivity such as acrylonitrile resin.