EP0506295B1

EP0506295B1 - Reclosable food package

Info

Publication number: EP0506295B1
Application number: EP92302343A
Authority: EP
Inventors: Drew H. Moore; Daniel A. Thiemann; Francis Regis Finn
Original assignee: Oscar Mayer Foods Corp
Current assignee: Oscar Mayer Foods Corp
Priority date: 1991-03-26
Filing date: 1992-03-18
Publication date: 1995-05-17
Anticipated expiration: 2012-03-18
Also published as: CA2063201A1; ES2072705T3; MY129930A; JPH0585542A; DE69202505T2; KR920017921A; CN1065251A; ATE122636T1; TW212781B; NZ242100A; HK3997A; EP0506295A1; DE69202505D1

Abstract

An improved reclosable food package characterized by good reclosure performance and improved moldability is provided in a package including a receptacle cover member, a base member, an optional hermetic seal between the cover and the base and hemi-elliptical interlocking engagement features with a chamfered portion. <IMAGE>

Description

The present invention relates to a food package having a base member, cover member, a peelable seal for hermetically sealing the base to the cover and releasable locking means formed in the base and cover for reclosing the package after it has been opened. More particularly, it relates to a new and improved reclosable package having inter-engaging locking lugs with an improved depth and configuration to provide better reclosure performance after opening.
Many food packages are described in the patent literature. For example, in US-A-3,498,018, a food package is described wherein the food is sealed inside the package having a body and a top member. The food is placed in one part of the package and a cover is placed thereon under vacuum and with mechanical pressure, thereby forming the food to the package, and the base and cover are hermetically sealed. These types of packages and methods for forming them are further described in US-A-4,411,122; US-A-4,577,757 and US-A-4,688,369. Attempts to improve these patents are further described in US-A-4,498,588 and US-A-4,498,589. Various improvements are described, for instance in US-A-4,498,589, wherein ridges 34 and grooves 36, shown in Fig. 3 are described in an attempt to provide an interlocking engagement. The ridges and grooves mentioned in this patent are not described as having any particular configuration and appear to be formed in a double action or side action mold. Other means of incorporation snap actions into packages are described in US-A-3,672,536 and US-A-3,734,276. It is submitted that these two patents, however, do not describe packages wherein the package foods are formed to the package with vacuum and mechanical pressure.
More recently, in US-A-4,944,134 and US-A-4,945,710, still other reclosable packages provided with snap-action locking features are described. Each of these patents disclose a secondary operation in the form of a post-thermoforming crimping operation, to impart complementary snap locking features in the base and cover members.
WO-A-84/03079 discloses a food package corresponding to the preambles of claim 1 and claim 8 formed from a semi-rigid base and cover, the base comprising a raised panel surrounded by a planar flange. The raised panel is telescopically received in the cover and is snap-locked thereto.
In accordance with these prior art reclosable food packages, the packaged product is offered for sale in an evacuated or gas flushed, adhesively bonded or heat bonded, hermetically sealed condition. To open the package, a consumer grips a corner or flange on the base member in one hand and a flange on the cover member in the other hand and pulls them outwardly and apart to dislodge the base member from the cover member. The base portion includes a raised pedestal portion which is telescopically received in the food receiving recess or compartment of the cover member. The raised pedestal portion of the base includes a raised food-contact surface, a spaced planar peripheral flange extending generally parallel to the food contact surface, and a vertical sidewall surface extending between and interconnecting the base flange to the food contact surface. The matable cover member includes a food receiving compartment which may be a central cylindrical or rectangular recess defined by an endwall and an upstanding sidewall. A planar peripheral flange portion extends outwardly from the end of the cover sidewall, thereby circumscribing a generally circular or rectangular opening or entrance aperture to the cup shaped food-receiving compartment.
In accordance with these conventional packages, reclosable features in the form of cooperating concave and convex tugs, usually having semi-circular configuration, are provided along the vertical sidewall portion of the base member and along a lower margin portion of the upstanding cover side wall adjacent the cover flange. The package is closed by urging the base pedestal portion through the compartment opening so that it is telescopically received in the food-receiving cavity. The lug formations provided in the sidewall portions of the base and cover are inter-engaged in the telescoping closure and the cover flange is disposed in overlying registration with respect to the base flange. A seal is defined between the base and cover flange portions adjacent the food-receiving compartment area.
In these prior art packages, a problem may be encountered when the packages are first opened and the hermetic seal is first broken. Generally, the forces required to separate cover and base member are great enough so that distortion of the base member may occur. As a result, the flange portions and sidewall portion on the base may be deformed to such an extent that the base no longer seats properly into the cover member and the reclosable lug features do not effectively cooperate to satisfactorily reclose the package after opening. Proposed solutions to overcome the deformation problem have included: molding the base members out of thicker section materials and increasing the depth of the lugs formed in the sidewall portions to improve inter-engagement. Increasing the thickness of the base material to improve its stiffness and dimensional stability during opening disadvantageously increases the cost of the overall package, which is undesirable.
Prior efforts to increase the depth of the interengaging semi-circular lug formations lead to problems with molding the parts. More particularly, the parts with deeper lugs either could not be released from a conventional mold, i.e., become stuck, or the parts were deformed or distorted in the unmolding process so that their sealing and reclosing features did not work appropriately. To achieve increased lug depth with the prior art lug configurations, molding in more complex molds, such as side action molds, is generally required which would also undesirably increase the costs of providing a satisfactory reclosable package.
To overcome the disadvantages of the prior art food packages, it is an object of the present invention to provide a food package that is easily opened which, after opening, recloses in a positive manner providing a sensible indication to the consumer that the package has been fully reclosed and which generally will not become opened or separated unintentionally in use.

SUMMARY OF THE INVENTION

In accordance with these and other objects, the present invention provides a reclosable food package comprising:
a pedestal base member including a first generally planar peripheral flange portion, a generally central food receiving platform defined by a raised major surface extending generally parallel to said first peripheral flange portion in spaced relation therewith and a vertical sidewall portion extending between and interconnecting said food-receiving platform and said first peripheral flange portion;
a receptacle cover member including a second generally planar peripheral flange portion and a body portion defining a food receiving cavity, an outwardly stepped margin portion of said cover body portion adjacent said second peripheral flange portion being configured to closely telescopically receive the raised platform and sidewall portion of the base member when the second flange portion of the cover member is disposed in registering face to face contact with the first flange portion of the base member; and
releasable interlocking engagement means for retaining the cover member and base member together in an assembled condition including at least one lug projection extending outwardly from said vertical sidewall portion of the base member intermediate the height thereof, said interlocking engagement means further including at least one complementary lug-receiving recess defined in said margin portion of said cover member and being configured to substantially completely telescopically receive a said lug projection,
characterised in that each said lug projection has a generally hemi-elliptical cross sectional configuration in vertical section including a first upper radiussed portion disposed adjacent and spaced from said raised major surface, an intermediate flat portion, a second lower radiussed portion and a chamfer portion extending between the second radiussed portion and a lower end of said vertical sidewall adjacent said first peripheral flange, and that each said lug-receiving recess has a corresponding hemi-elliptical cross-sectional configuration whereby, in the assembled condition, the chamfered portions of the lug projection and lug-receiving recess are aligned in abutment with each other.
It further provides a reclosable food package comprising:
a pedestal base member including a first generally planar peripheral flange portion, a generally central food-receiving platform defined by a raised major surface extending generally parallel to said first peripheral flange portion in spaced relation therewith and a vertical sidewall portion extending between and interconnecting said food-receiving platform and said first peripheral flange portion;
a receptacle cover member including a second generally planar peripheral flange portion and a body portion defining a food receiving cavity, an outwardly stepped margin portion of said cover body portion adjacent said second peripheral flange portion being configured to closely telescopically receive the raised platform and sidewall portion of the base member when the flange portion of the cover is disposed in face to face contact with the flange portion of the base; and
releasable interlocking engagement means for retaining the cover member and base member together in an assembled condition including at least one lug-receiving recess extending inwardly from said vertical sidewall portion of the base member intermediate the height thereof, said interlocking engagement means further including at least one complementary lug projection defined in said margin portion of said cover member and being configured to be substantially completely telescopically received in a said lug-receiving recess;
characterised in that each said lug-receiving recess has a generally hemi-elliptical cross-sectional configuration including a first lower radiussed portion disposed adjacent and spaced from said peripheral flange portion, an intermediate flat portion, a second upper radiussed portion and a chamfer portion extending between the second radiussed portion and an upper end of said vertical sidewall adjacent said raised major surface; and that each said lug projection has a corresponding hemi-elliptical cross-sectional configuration whereby, in the assembled condition, the chamfered portions of the lug projection and the lug-receiving recess are aligned in abutment with each other.
The special configuration of the cooperating locking features of the new and improved food package provide an effectively reclosable package after opening which also simultaneous permits the packages to be formed in vacuum thermoforming molding operations.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a perspective view of the new and improved reclosable food package of the present invention;
Fig. 2 is an elevated cross sectional view, partially cut away to show the improved releasable interlocking engagement features of the package of this invention shown in an assembled or closed food storage condition; and
Fig. 3 is an elevated fragmentary cross sectional view showing an alternate embodiment of the new and improved releasable interlocking engagement features in an alternate food package in accordance with this invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to Figs. 1-2, a new and improved reclosable food storage package or container 10 is shown. Package 10 is of a well known type for storing sliced luncheon meats and cheeses for example in a vacuumized, hermetically sealed package. Often referred to as a "pedestal package" or a "bubble package", package 10 includes a pedestal base member 12 and a receptacle cover member 14.
The pedestal base member 12 includes a planar peripheral flange portion 16 having a generally rectangular peripheral configuration. A generally centralized, cylindrical food-contacting platform 18 defined by a major surface 20 extends in a raised position, spaced from flange portion 16 but extending generally parallel to flange 16. A vertical sidewall portion 22 extends between major surface 20 and flange portion 16. Vertical sidewall 22 is connected at its lower end 24 to flange portion 16 by a corner 26. As shown in Fig. 2, the angle between lower end 24 of sidewall 22 and flange 16 is preferably slightly greater than 90 degrees. The vertical sidewall 22 is connected at its opposed upper end to major surface 20 by an upper corner 28. A gradually sloping central recess or depression 30 may be defined in the surface 20 of food-contacting platform 18 as shown, to facilitate vacuumizing the package and to collect product moisture. Accordingly, the upper corner 28 preferably includes an angle slightly less than 90 degrees as shown.
The receptacle cover member 14 also includes a planar peripheral flange portion 32 having a generally rectangular peripheral configuration. A body portion 34 extends upwardly from one side of the flange portion 32 to define a generally cylindrical food receiving cavity or package interior enclosure 36. A plurality of horizontally extending mini-ribs 38 and vertically extending ribs 40 are defined in body portion 34 to improve vacuumization and package appearance.
The body portion 34 includes an endwall 42 capable of being molded to include various indicia to indicate the product source and an upstanding sidewall 44 extending between flange portion 32 and endwall 42. Cover sidewall 44 includes a lower margin portion 46 adjacent flange portion 32 which is adapted to closely, telescopically receive the raised food-contacting platform 18 and vertical sidewall portion 22 of the base member 12. Endwall 42 has a generally circular configuration having a diameter, a, which is slightly less than the diameter, b, defined at the entrance opening 48 (Fig. 2) to the food-receiving cavity 36 at the point where margin portion 46 intersects flange 32.
Accordingly, although upstanding sidewall 44 of the cover 14 has a stepped configuration, as shown in the preferred embodiment in Fig. 2, sidewall 44 generally extends between endwall 42 and flange portion 32 at a slightly angled orientation so that the angle of sidewall 44 to flange 32 is slightly greater than 90 degrees. As a result, the body portion 34 of the cover 14 and the raised food receiving platform 18 of the base member 12 are each provided with a slight or gradual frusto-conical tapering from the flange portions toward the endwall.
In accordance with the present invention, improved reclosure performance after opening and improved moldability are provided in package 10 by an improved releasable interlocking engagement means, generally referred to by reference numeral 50, and including at least one lug projection 52 extending outwardly from base sidewall portion 22 at a point intermediate the height thereof and a complementary lug-receiving recess 54 defined in the margin portion 46 of cover member 14.
More particularly and referring to Fig. 2, each lug projection 52 is specially molded to have a generally hemi-elliptical cross sectional configuration, as shown in section at the left hand portion of Fig. 2. The longitudinal axis of the hemi-elliptical cross sectional configuration extends parallel to the height dimension of base sidewall portion 22, as indicated by dimension c. Lug projection 52 includes a first upper radiussed portion 56 disposed at the upper end of lug projection 52 adjacent the major surface 20. A lower, second radiussed portion 58 is spaced from the first radiussed portion 56 and extends adjacent the corner 26 in overlying relation to flange portion 16. An intermediate flat portion 60 extends between and interconnects the upper and lower radiussed portions 56 and 58, respectively. A chamfer portion 62 extends between and interconnects lower radiussed portion 58 and lower end 24 of sidewall 22. Although the chamfer angle, g, of chamfer portion 62 may be varied between about 20 to 80 degrees a preferred angle g is between about 30 to 60 degrees. An especially preferred chamfer angle g is 30 degrees.
The lug-receiving recesses 54 are provided with a complementary hemi-elliptical cross sectional configuration also including an upper radiussed portion 66, a lower radiussed portion 68 and a flat intermediate portion 70. Flat intermediate portion 70 has a length, e, which is slightly longer than the corresponding length, d, of flat intermediate portion 60 on lug projection 52. The lower end of lug receiving recess 54 also includes an aligned cooperating chamfer portion 72.
In use, the flange portions 16 and 32 are positioned in registering confronting relation to each other. In this position, the raised food contacting platform 18 is disposed in the opening 48 to the food-receiving cavity. Thereafter, upon further urging of the base 12 and the cover 14 together, the lower end portion of the margin 46 moves over the upper radiussed portion 56 of the projecting lug 52 to slide along flat intermediate surface 60 until it clears second radiussed portion 58. Thereupon, the end portion is free to resile inwardly so that the chamfer 72 is in abuttingly aligned relation with chamfer portion 62. The cover member 14 can only be dislodged from its engaged, closed or assembled condition on the base 12 by supplying a separation/withdrawal force sufficient to cause the margin portion 46 of the cover to move away from sidewall 22 by a displacement sufficient to override the profile of the lug member 52. The magnitude of standoff or depth dimension, f, of lug 52 is important in providing improved reclosure performance properties after opening.
In accordance with this aspect of the invention, it has been discovered that after the adhesively sealed packages of this invention are peeled open and after some of the sliced food product is removed, the base portion may be pressed back into a closed position in the cover in a manner providing an audible, and/or tactile pop or snap lock indication of effective reclosure. Thereafter, when the packages of this invention are gripped by the body portion and inverted, the base does not become dislodged from the cover even after shaking the package so that the food contents act as a hammer against the base platform in an effort to dislodge the base from the cover. When the invert and shake test is performed on prior art semi-circular lug packages, the base members were relatively easily dislodged and separated from their covers as compared with the improved packages of this invention.
In accordance with this invention, the lug 52 and the lug-receiving recess 54 are each provided with a hemi-elliptical cross sectional configuration having an increased depth dimension, f, which provides better cooperative reclosure engagement of the base and cover members without increasing the cross sectional thickness of the base sheet. The chamfered undercut portions 62 and 72 permit the parts to be vacuum form molded without the need for a complex mold (such as a side action mold) to provide satisfactory mold release characteristics for the product packaging. In addition to not deforming on release from the molds, the lug configuration also appears to reduce or eliminate distortion or deformation of the parts on original opening by the consumer to break the hermetic seal. The chamfer portions 62 and 72 permit conventional molds with stripper plate technology to be employed without the need to resort to complicated, maintenance intensive and expensive complex molds, or to labor intensive secondary post-forming operations or to thicker part sections as has been proposed in the prior art.
In accordance with an advantage provided by this invention, the package parts may be made by conventional molding techniques, such as those described in US-A-3,498,018; US-A-4,411,122; US-A-4,577,757; and US-A-4,688,369, incorporated herein by reference. These patents describe a method or forming a vacuumized, hermetically sealed package, such as package 10 shown in the figures. Generally, a predetermined quantity of a product which is deformable is arranged in the bubble cover body cavity 36 in an upright mass on an inner surface of endwall 42. The base peripheral flange 16 is hermetically sealed to the corresponding peripheral flange 32 of cover member 14. Preferably, the cover member is made or a semi-rigid, preformed thermoplsatic material. A glue pattern of adhesives is applied around the periphery of the package to form an hermetic peel seal. The peel seal, usually a circular band of from about 1/8 of an inch to about 1/4 of an inch (about 3.18 mm to about 6.35 mm) in width is applied or formed by any means known to those skilled in the art.
To fill the package, the cover member 14 is placed in an inverted position and a sufficient quantity of product is placed in the food-receiving cavity 36 to substantially fill the cover member when the package is completed. The base 12 is positioned at the opening 48 of the body cavity 36 so that the raised product panel 18 is positioned to be telescopically received in the margin portion 46 of the cover member 14. The flange portions 16 and 32 margins of the base 12 and cover 14 are disposed in registration with each other. Mechanical pressure is applied to push the raised food receiving panel 18 into the cavity 36 and against the product placed therein. In d fully assembled and looked position, the base member 12 forces the product into close contact with the interior surfaces of the cover and base members to tightly pack the product within the interior cavity 36 and to substantially completely fill the space available between the package and the product while vacuumizing the assembly and adhesively sealing the package 10 in a hermetic manner.
The cover and base members 14 and 12, respectively, may each be made of the same or different resilient, semi-rigid thermoplastic food packaging material. Illustrative thermoplastics include polyolefins, polyesters, polycarbonates, polyamides, cellulose esters and blends and copolymers of any of the foregoing thermoplastic polymers. For example, polyolefins such as polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyacrylic and/or acrylonitrile resins and copolymers, ethylene vinyl acetate, alloys and blends or mixtures thereof may be used. Polyesters such as polyalkylene terephthalates, such as polyethylene terephthalate (PET) or polyacrylate esters may be employed. As polyamides, nylons or polymers or copolymers containing nylon type monomers, may be suggested. Cellulose acetate materials might also be used. Laminates of these materials may also be employed. Preferred thermoplastics for use herein include polyvinyl chloride, polyethylene terephthalate, SARANEX®-containing laminates and BAREX®-type modified polyacrylonitrile materials.
The adhesives for use in making the optional hermetic seal may be any of those known to those skilled in this art to be useful for this purpose. Illustrative adhesives may include peelable adhesives based on polyvinyl chloride, vinyl acetate, ethylene vinyl acetate, partially hydrolized vinyl chloride-vinyl acetates, styrene-butadiene resins and mixtures of any of the foregoing in printable formulations including suitable organic solvents, waxes, hydrocarbons, rosins and tackifiers. These adhesives are well known to those skilled in this art and are commercially available from H.B. Fuller and Findley Corporation, to name but a few.
As has been mentioned above, the new and improved releasable interlocking engagement lugs and lug-receiving recesses are each specifically designed to include a chamfered section to provide better reclosure performance and molding advantages in the parts enabling them to be mass produced in modern multi-cavity molds.
In accordance with this aspect of the invention, the depth, i.e., dimension f, of these lugs has been maximized but the sharpness of the undercut chamfer 62 on the lugs 52 has been made gradual so that the thermoformed parts may be easily ejected from a thermoforming mold using stripper plate technology well known to those skilled in this art. Sharply formed lugs with a definitive undercut cannot be released from a multiple part mold without making a split mold. Otherwise these sharply formed lugs must be imparted in a secondary operation. A split mold becomes impractically complicated and expensive for multiple units. Similarly, the material costs rise unacceptably as more space is provided for release mechanisms between multiple packages.
The new and improved lugs 52 and corresponding lug-receiving recesses 54 may vary in number from 1 to 24 or more and they may be intermittent or a continuous bead.
Referring now to Fig. 3, an alternate embodiment of the new and improved food package of the present invention, generally referred to by reference numeral 100, is shown. In this alternate package 100, the releasable interlocking engagement means has been modified from the embodiment shown in Figs. 1-2 so that instead of providing an outwardly projecting lug on the base, such as lugs 52, an inwardly directed recess 102 is provided; and instead of providing a recess, such as recesses 54, on the cover margin portion 46, an inwardly directed projecting lug 104 is provided. Moreover, although the same hemi-elliptical interlocking configurations are used for the lug and recess portions of the interlocking engagement members 102 and 104, the hemi-elliptical elements are inverted so that, instead of having the chamfered portions 62 and 72 disposed adjacent peripheral flanges 16 and 32, chamfer portions 62a and 72a are disposed opposite the peripheral flanges 16 and 32 adjacent the food contacting surface 20 of the raised platform 18. The beneficial advantages including improved reclosure performance after opening, improved lug and receptacle depth and mold release properties, are also provided by the modified releasable interlocking engagement structures shown in alternate food package 100.

EXAMPLES 1-3

In the following Examples, seven samples of packages molded in accordance with this invention and having the lug configuration shown in Figs. 1 and 2 were provided in 8 oz. (226.8g), 12 oz. (340.2g) and 16 oz. (453.6g) product package sizes, and tested. Adhesively sealed and unglued package samples were tested on Instron Corporation materials testing equipment to determine opening tensile forces required to peel open the glued or unglued packages. In accordance with these tests, a corner of the cover flange portion was secured in a jaw fixture of the machine. An opposing corner portion of the base flange was secured in the other jaw fixture. The machine was permitted to move the jaws apart and the maximum load required to open the packages was recorded.
Some of the samples were also tested for compressive reclosure forces required to effect interlocking engagement of the lug formations on the cover margin and base portion. In these tests the cover endwall was placed on a fixed platen. The base member was lightly placed against the opening of the cover member. A movable platen having a diameter approximately the same as the pedestal was placed against the underside of raised food-contacting surface of the base. The machine was activated to urge the base into the cover member to a fully seated depth and the maximum load to reclose the package was recorded.
The samples tested and the results obtained are set forth in TABLE 1, as follows:

All values are the average and standard derivation for seven specimens tested.

EXAMPLE 4

A number of 16 oz. (453.6g) food packages in accordance with this invention as shown in Figs. 1-2 and similar to those employed in Example 3 were filled with 16 oz. (453.6g) of luncheon meat and sealed in accordance with standard commercial procedures. Samples of prior art packages having rounded semi-circular reclosable lug configurations, such as shown in US-A-3,498,018, were tested for reclosure performance after opening. The commercially sealed packages were opened by hand by gripping opposing corners of the flanges on the base and cover portions until the base was completely peeled off of the cover. A couple of slices of the pre-sliced luncheon meat product were removed from each of the packages. The inverted covers containing the remaining product portion were placed on a flat table top and the base members were aligned and pressed into closed position. The packages were turned over so that they each rested on their base portions. The cover portions of each package were gripped by the fingers, care being taken not to deform the sidewall of the cover members. The gripped packages were lifted and vertically shaken lightly so that the remaining package contents acted as a hammer and fell against the base of the package. In accordance with this test method the sample packages in accordance with this invention did not re-open or separate during the "invert and shake test". In the commercially available prior art packages having semi-circular lug formations, the bases all separated from the covers and the product fell out of the cover recess areas. From this test it was concluded that packages incorporating the new and improved chamfered hemi-elliptical lug configuration in accordance with this invention exhibited improved reclosure performance after opening than the semi-circular lug packages of the prior art.
Although the present invention has been described with reference to certain preferred embodiments, modifications or changes may be made therein by those skilled in this art. The benefits of the new and improved reclosable food package in accordance with this invention may be provided in a package made in generally any overall shape or configuration. For example, the shape of the food-receiving compartment or bubble portion may be substantially any desired shape and it may be the same or different from the peripheral shape of the outer flange portions. Instead of a cylindrical food package adapted to receive circular sliced foods, a rectangular, oval or teardrop shaped food package may also be prepared in accordance with this invention. All such obvious modifications may be made herein without departing from the scope of the present invention as defined in the appended claims.

Claims

A reclosable food package (10) comprising:
a pedestal base member (12) including a first generally planar peripheral flange portion (16), a generally central food receiving platform (18) defined by a raised major surface (20) extending generally parallel to said first peripheral flange portion (16) in spaced relation therewith and a vertical sidewall portion (22) extending between and interconnecting said food-receiving platform (18) and said first peripheral flange portion (16);
a receptacle cover member (14) including a second generally planar peripheral flange portion (32) and a body portion (34) defining a food receiving cavity (36), an outwardly stepped margin portion (46) of said cover body portion (34) adjacent said second peripheral flange portion (32) being configured to closely telescopically receive the raised platform (18) and sidewall portion (22) of the base member (12) when the second flange portion (32) of the cover member (14) is disposed in registering face to face contact with the first flange portion (16) of the base member (12); and
releasable interlocking engagement means (50) for retaining the cover member (14) and base member (12) together in an assembled condition including at least one lug projection (52) extending outwardly from said vertical sidewall portion (22) of the base member (12) intermediate the height thereof, said interlocking engagement means (50) further including at least one complementary lug-receiving recess (54) defined in said margin portion (46) of said cover member (14) and being configured to substantially completely telescopically receive a said lug projection (52);
characterised in that each said lug projection (52) has a generally hemi-elliptical cross sectional configuration in vertical section including a first upper radiussed portion (56) disposed adjacent and spaced from said raised major surface (20), an intermediate flat portion (60), a second lower radiussed portion (58) and a chamfer portion (62) extending between the second radiussed portion (58) and a lower end of said vertical sidewall (22) adjacent said first peripheral flange (16); and
that each said lug-receiving recess (54) has a corresponding hemi-elliptical cross-sectional configuration whereby, in the assembled condition, the chamfered portions (62, 72) of the lug projection (52) and lug-receiving recess (54) are aligned in abutment with each other.
A food package according to claim 1, characterised in that the base member (12) and the cover member (14) are pre-formed, independently molded members.
A food package according to claim 1 or claim 2, characterised in that the base member (12) and the cover member (14) are resilient semi-rigid thermoplastic molded members.
A food package according to any one of claims 1 to 3, characterised in that the food-receiving platform (18) and body portion (34) each have a generally circular peripheral configuration.
A food package according to any one of claims 1 to 3, characterised in that the food-receiving platform (18) and the body portion (34) each have a generally rectangular peripheral configuration.
A food package according to any one of claims 1 to 5, characterised in that it further includes adhesive means disposed on said first peripheral flange portion (16) and said second peripheral flange portion (32) for bonding and hermetically sealing the base member (12) and the cover member (14) together.
A food package according to claim 6, characterised in that said adhesive means is disposed immediately adjacent said vertical sidewall portion (22) of the base member (12).
A reclosable food package (100) comprising:
a pedestal base member (12) including a generally planar peripheral flange portion (16), a generally central food-receiving platform (18) defined by a raised major surface (20) extending generally parallel to said first peripheral flange portion (16) in spaced relation therewith and a vertical sidewall portion extending between and interconnecting said food-receiving platform (18) and said first peripheral flange portion (16);
a receptacle cover member (14) including a second generally planar peripheral flange portion (32) and a body portion defining a food receiving cavity (36), an outwardly stepped margin portion of said cover body portion adjacent said second peripheral flange portion (32) being configured to closely telescopically receive the raised platform (18) and sidewall portion of the base member (12) when the second flange portion (32) of the cover member (14) is disposed in face to face contact with the first flange portion (16) of the base member (12); and
releasable interlocking engagement means for retaining the cover member (14) and base member (12) together in an assembled condition including at least one lug-receiving recess (102) extending inwardly from said vertical sidewall portion of the base member (12) intermediate the height thereof, said interlocking engagement means further including at least one complementary lug projection (104) defined in said margin portion of said cover member (14) and being configured to be substantially completely telescopically received in a said lug-receiving recess (102);
characterised in that each said lug-receiving recess (102) has a generally hemi-elliptical cross-sectional configuration including a first lower radiussed portion disposed adjacent and spaced from said first peripheral flange portion (16), an intermediate flat portion, a second upper radiussed portion and a chamfer portion extending between the second radiussed portion and an upper end of said vertical sidewall adjacent said raised major surface (20); and
that each said lug projection (104) has a corresponding hemi-elliptical cross-sectional configuration whereby, in the assembled condition, the chamfered portions of the lug projection (104) and the lug-receiving recess (102) are aligned in abutment with each other.
A reclosable food package according to any one of claims 1 to 8, characterised in that said sidewall portion (44) of cover member (14) and said sidewall portion (22) of base member (12) each have a gradual frusto-conical tapering from the flange portions (16, 32) toward an endwall (42) of said cover member (14).