Covered airtight container

A covered airtight container capable of preventing a soup from leaking therefrom. The covered airtight container comprises a body made of hard plastics and a cover made of soft plastics wherein the cover has a reverse channel-shaped edge portion piece formed by bending the upper end edge thereof upward and reversing it downward so as to cover the upper end portion of the body. The body has an annular stepped portion to which the cover is retained at the inner peripheral surface of the upper end portion of the peripheral wall. The cover has an annularly projected fin for elastically contacting the edge of said annular stepped portion. The covered airtight container may be formed square shaped with circumferential surfaces of the body and cover being slightly curved shape close to a circle. Particularly, the leaking prevention effect can be conspicuous since the sealing effect or state is assured at the inner and outer surfaces of the peripheral wall of the body. Even if the edge portion piece is pulled off after the cover is open so that the vertical double annular projection of the body is disengaged from the vertical annular grooves, the soup is prevented from leaking because of the annular fin of the cover. As a result, the container can be used even after the cover is open. When the covered airtight container is formed square shaped while the circumferential surfaces of the body and cover are formed in a curved shape, it does not occupy much space during transportation or the keeping thereof and the end of the edge portion piece of the cover can be cut off along the upper annular groove, which is very convenient for handling.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to a covered airtight container made of 
plastics for packing and selling processed foodstuffs such as fishes, 
shellfishes and edible wild plant, etc. 
2. Prior Art 
There has been widely employed a covered airtight container comprising a 
body made of hard material and a cover made of flexible material in which 
the body has a projection at an upper end outer peripheral surface of a 
peripheral wall and the covet- has an edge portion piece formed by bending 
the upper end edge thereof upward and reversing it downward for engaging 
with the upper end portion of the peripheral wall of the body. The cover 
also has and an annular groove at the inner peripheral surface of the edge 
portion piece for engaging in the projection of the body. In such a prior 
art covered airtight container, the sealing state of the cover is stable 
if the projection of the body is triangular in cross section to Form a 
clearance angle at the lower portion. However, the edge portion piece of 
the cover must be cut off along the annular groove since the cover can not 
be removed from the body as it is. As illustrated in FIG. 1, a notched 
window 29 is provided at a part of the edge portion piece 17. A cutoff 
device 4 comprises a knob 31 which is provided on the lower end portion 
17A of the edge portion piece 17 and disposed at the lower end portion of 
the notched window 29. The knob 31 projects from one end of the lower end 
portion of the notched portion 29 and connects to the other end thereof at 
a point connection 33. If the knob 31 is pulled out and cut off at the 
point connection 33, the lower end portion 17A of the edge portion piece 
17 can be pulled off. 
An advantage of such a prior art covered airtight container, there is that 
soup does not leak from the container because of the airtight connection 
between the projection of the body and the groove of the cover and the 
cover does not come off until it is opened. However, the disadvantage is 
that there is a possibility that the soup leaks when the body is thermally 
expanded or shocked during its conveyance because the body and the cover 
are connected by a single projection and groove. Particularly, when the 
cover is open, namely, the body is uncovered, the soup is liable to leak 
because of there is no connection between the annular projection and the 
annular groove. This is true even if the cover is closed, namely, the body 
is covered by the cover. 
SUMMARY OF THE INVENTION 
Under the circumstances, it is an object of the invention to provide a 
covered airtight container capable of effectively preventing soup from 
leaking. 
To achieve the above object, a first aspect of the invention is to provide 
a covered airtight container comprising a body made of hard plastics and a 
cover made of soft plastics wherein the cover has a reverse channel-shaped 
edge portion piece formed by bending the upper end edge thereof upward and 
reversing it downward so as to cover the upper end portion of the 
peripheral wall of the body. The body has vertically arranged double 
annular projections at the outer peripheral surface of the upper end 
portion of the peripheral wall, each annular projection being triangular 
in cross section to form a clearance angle at the lower portion. The edge 
portion piece of the cover has vertically arranged double annular grooves 
for engaging with the annular projections of the body and the cover is 
also provided with a cutoff means extending along the upper annular groove 
of the cover for opening the cover. 
A second aspect of the invention is to provide a covered airtight container 
comprising a body made of hard plastics and a cover made of soft plastics 
wherein the cover has a reverse channel-shaped edge portion piece formed 
by bending the upper end edge thereof upward and reversing it downward so 
as to cover the upper end portion of the peripheral wall of the body. The 
body has an annular stepped portion to which the cover is retained, at the 
inner peripheral surface of the upper end portion of the peripheral wall 
and the cover has an annular fin for elastically contacting the edge of 
the annular stepped portion. 
A third aspect of the invention is to provide a covered airtight container 
of the first aspect of the invention wherein the same structure as the 
second aspect of the invention is added to this covered airtight 
container. 
A fourth aspect of the invention is to provide a covered airtight container 
of the first and third aspect of the inventions wherein the body and cover 
are square shaped with corners that are slightly curved and the 
circumferential surfaces of the body and cover being slightly arched. 
Since the vertically arranged double annular projections provided at the 
upper end portion of the peripheral wall of the body are triangular in 
cross section to form a clearance angle at the lower portion, the edge 
portion piece of the cover can cover the upper end portion of the 
peripheral wall of the body, whereby the vertical double annular 
projections and the annular grooves are combined with one another, which 
assures the airtight sealing at the portion between the outer surface of 
the peripheral wall. Furthermore, in the inner surface of the body, the 
annular fin of the cover elastically contacts the annular stepped portion 
of the body, which also assures the airtight sealing. 
Still Furthermore, when the body and the cover are formed in square shapes, 
the airtight container does not occupy much space and the end of the edge 
portion piece of the cover can be cut off along the upper annular grooves 
of the cover since they are curved along the entire circumference thereof. 
When the cover is on the body the cover can not be opened because of the 
engagement of annular grooves thereof with the annular projections of the 
body. Therefore, the edge portion piece of the cover needs to be cut off 
along the upper annular groove by the cutoff device so that the vertically 
arranged double grooves are disengaged from the vertical double 
projections when the cover is open.

PREFERRED EMBODIMENT OF THE INVENTION 
Preferred Embodiment (FIGS. 1 and, 2): 
A covered airtight container according to a preferred embodiment will be 
described with reference to FIGS. 1 and 2. 
A covered airtight container comprises a body 1 formed by injection 
molding, namely, molded out of hard plastics and a cover 3 formed by the 
same injection molding, namely, molded out of soft plastics wherein the 
airtight container is sealed at the inner and outer surfaces of a 
peripheral wall 5 of the body 1. A cutoff device 4 is provided for 
releasing the sealed state of the inner side of the air container. The 
airtight container is circular as a whole but may be square shaped. 
There are provided on the outer surface of the peripheral wall 5 of the 
body 1 a stepped portion 7 in a projected form all the portion close to 
the upper end thereof and double annular projections 9 and 11 which are 
positioned above the stepped portion 7 and which are triangular in cross 
section to form, respectively, a clearance angle at the lower portion 
thereof wherein the lower annular projection 11 is smaller than the upper 
annular projection 9. With such an arrangement, the body 1 can be easily 
covered by the cover 3. 
There is provided on the inner surface of the peripheral wall 5, an annular 
stepped portion 13 which is positioned over the projecting stepped portion 
7, wherein the lower portion of the annular stepped portion 13 is 
perpendicular to the annular stepped portion 13. There is also provided an 
annular concave portion 15 which is slightly curved in an arc in cross 
section at the upper portion of the annular stepped portion 13. 
The cover 3 has a reverse channel-shaped edge portion piece 17 which is 
formed by bending the upper end edge thereof at the portion where it is 
retained by the annular stepped portion 13 of the body 1 upward and 
reversing it downward so as to cover the upper end portion of the body 1. 
The reverse channel-shaped edge portion piece 17 of the cover 3 has 
vertically arranged double annular grooves 19 and 21 for engaging with the 
annular projections 9 and 11 of the body 1. Since the lower annular groove 
21 is shallower than the upper annular groove 21, when the body 1 is 
covered by the cover 3, the cover 3 easily passes the upper annular groove 
21 and is not caught by the upper annular groove 21, which easily assures 
the covering of the body 1. When the edge portion piece 17 is cut off by 
the cutoff device 4, the cover is cut off at the portion where the upper 
annular groove 19 is positioned. 
The cover 3 also has an annular fin 23 which is elastically retained by the 
edge of the annular stepped portion 13 of the body 1. The cover 3 also has 
an annular convex portion 25 which engages with the annular concave 
portion 15 of the body 1. With the engagement of the annular convex 
portion 25 and the annular concave portion 15, the soup is prevented film 
leaking and the connection of the body 1 and the cover 3 can be stabilized 
after the lower end portion 17A of the edge portion piece 17 is cut off. 
The peripheral wall 5 of the body 1 is connected to the edge portion piece 
17 of the cover 3 in an airtight condition where no space is defined 
between the peripheral wall 5 and the edge portion piece 17. There are 
defined slight spaces 26A and 26B between the peripheral wall 5 and the 
edge portion piece 17 at the portion lower than the upper annular 
projection 9 so as to improve the airtightness between the annular 
projections 9 and 11 and the annular grooves 19 and 21. There is defined a 
space 27 between the annular stepped portion 13 of the body 1 and the 
cover 3 at the portion close to the annular fin 23 of the cover 3 so that 
the annular fin 23 can perform a line contact with the annular stepped 
portion 13 so as to obtain contact therebetween under pressure at the 
entire surface thereof. 
If the edge portion piece 17 is pressed into the upper end of the 
peripheral wall 5 of the body 1 while the body 1 is covered by the cover 
3, the vertically arranged double annular projections 9 and 11 are 
connected to the annular grooves 19 and 21. Hence the cover 3 can not be 
opened unless the connections therebetween are released. Accordingly, the 
cutoff device 4 is structured to cut off the edge portion piece 17 along 
the upper annular groove 19. 
The cutoff device 4 is provided with a notched window 29 for assuring the 
cut off position of the cutoff device 4. The upper edge of the notched 
window 29 is positioned at P which corresponds to the innermost portion of 
the upper annular groove 19. A knob 31 is provided on the lower end 
portion 17A of the edge portion piece 17 and disposed at the lower end 
portion of the notched window 29 in the manner of projecting from one end 
of the lower end portion of the notched portion 29 and connecting to the 
other end thereof at a point connection 33. If the knob 31 is pulled out 
and cut off at the connecting portion 33, the lower end portion 17A of the 
edge portion piece 17 can be pulled off at the entire circumference 
thereof at the position of the upper annular groove 19. 
When the edge portion piece 17 is pulled off at the lower end portion 17A, 
the annular groove 19 and 21 are released from the engagement with the 
vertically arranged double annular projections 9 and 11 so that the cover 
3 can be opened. However, if the body 1 is covered by the cover 3, 
airtightness between the cover 3 and the peripheral wall 5 can be 
obtained, which prevents the soup from leaking. Particularly, the 
prevention function is large because of the contact of the annular fin 23 
under pressure with the annular stepped portion 13 of the body 1. 
Modification (FIGS. 3 and 4): 
A covered airtight container according to a modification will be described 
with reference to FIGS. 3 and 4. 
The body 1 and the cover 3 of the covered airtight container are both 
formed square shaped with corner and sides that are slightly curved the at 
the entire circumferences thereof. That is, each side of the square cover 
3 is formed in a curved shape close to the arc of a large circle and each 
cornered portion 3B is formed in a curved shape close to the arc of a 
small circle. With such an arrangement, as the characteristics of the 
square shape, even if the volume of the square container is the same as 
that of the circular container, there is an advantage that the former does 
not occupy more surface than the latter during packaging. 
Since the upper annular groove 19 is curved at the entire circumference 
thereof different, from the square airtight container, the lower end 
portion 17A of the edge portion piece 17 can be smoothly cut off by the 
cutoff device 4 along the upper annular groove 19. If the container is 
true square, there is a disadvantage that greater force must be applied to 
cut off the lower end portion 17A of the edge portion piece 17 which may 
cause the cornered portions to be pulled off. 
When the lower end portion 17A of the edge portion piece 17 of the cover 3 
is cut off, the knob 31 is pulled out at the notched portion 29. The knob 
31 has an expansion portion 31A in cross section which can be easily 
pulled out. The lower annular projection 11 is formed like an apex of an 
isosceles triangle. Furthermore, the cover 3 has a winding piece 30 over 
the notched portion 29 (seen at the left in FIG. 4) so that the cover 3 
can be easily opened. The winding piece 30 prevents the point connection 
portion 33 from being carelessly cut if the knob 31 contacts other objects 
during the conveyance thereof. 
Materials such as polystyrene (PS), high-impact polystyrene (HiPS), 
acrylonitrile-styrene resin (AS), acrylonitrile-butadiene-styrene resin 
(ABS), polycarbonate (PC), etc. can be used as the hard plastics of the 
body 1. Material such as polyethylene, polypropylene, etc. can be used as 
the soft plastics of the cover 3. 
The covered airtight container of the present invention can effectively 
prevent soup contained therein from leaking. 
Particularly, this leak prevention effect is conspicuous according to the 
third aspect of the invention since the sealing effect or state can be 
assured at the inner and outer surfaces of the peripheral wall of the 
body. Even if the edge portion piece is pulled off after the cover is open 
so that the vertically arranged double annular projections of the body are 
disengaged from the vertically arranged annular grooves, the soup is 
prevented from leaking because of the annular fin of the cover. As a 
result, the covered airtight container can be used even after the cover is 
open. 
Although the airtight container is formed square shaped according to the 
fourth aspect of the invention, so as not to occupy much space during the 
conveyance or the keeping thereof, it is very convenient for handling 
since the end of the edge portion piece of the cover can be cut off along 
the upper annular groove.