US3625413A - Egg carton - Google Patents

Abstract

A molded polymeric container for fragile articles such as eggs, employing unique closure and latching features between the cover means and the container bottom. It involves special camming and latching between the ends of the cover means and the ends of the bottom member. The cover means has a pair of cover members with a special cooperative overcenter action during closure combined with the latching feature to obtain and maintain effective closure.

Description

United States Patent Inventor Roger L. Medendorp Grand Rapids, Mich. Appl. No. 832,692 Filed June 12, 1969 Patented Dec. 7, 1971 Assignee Gloucester Engineering Co., Inc.

Gloucester, Mass.

EGG CARTON 6 Claims, 7 Drawing Figs.

US. Cl 229/44 R, 229/25, 229/45 Int. CL 865d 85/32 Field of Search 229/44, 45, 2.5

[56] References Cited UNITED STATES PATENTS 3,498,526 3/1970 Edwards Primary Examiner-Donald F. Norton Attorney-John Noel Williams ABSTRACT: A molded polymeric container for fragile articles such as eggs, employing unique closure and latching features between the cover means and the container bottom. it involves special camming and latching between the ends of the cover means and the ends of the bottom member. The cover means has a pair of cover members with a special cooperative overcenter action during closure combined with the latching feature to obtain and maintain efiective closure.

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EGG CARTON BACKGROUND OF THE INVENTION This invention relates to molded containers, and more particularly to molded, polymeric containers for fragile articles such as eggs.

The production and marketing of molded egg cartons has heretofore generally been dominated by a few manufacturers employing molded pulp as the forming material. Repeated attempts have been made over the past several years to employ polymeric materials for egg cartons and the like. Some of these attempts have involved extensive and expensive development programs. If effective carton latching could be developed without significantly increasing the amount of material necessary, polymeric materials would present an attractive and effective carton. The cost of polymeric materials is far greater than that of pulp, and, effective polymeric carton latches have required more material. Some have been subjected to limited marketing, but, as is commonly known, polymeric egg cartons are sufficiently more expensive than pulp cartons as to be at a serious competitive disadvantage.

SUMMARY OF THE INVENTION It is a primary object of this invention to provide a molded polymeric container for articles such as eggs, capable of being readily molded on production equipment and having an excellent closure and latching action, without requiring excessive material so as to make it prohibitive in cost.

It is an object of this invention to provide a polymeric carton construction for articles such as eggs, having a unique cover latching feature. The ends of the cover are specially configurated to resiliently latch with the ends of the carton bottom. Protrusion means on one of the members, to interfit with recess means on the other member, cooperates with special camming means to impart a resilient bias between the cooperative latching portions.

Another object of this invention is to provide a polymeric carton construction for articles such as eggs having a unique double-cover, overcenter closure feature. The cover overcenter are hinged to the container bottom by integral hinges lying generally in the same plane, with the distance between these hinges on opposite edges of the container being less than the combined distances between the lower edge of the cover inner side panels and the hinges to cause the overcenter action tending to keep the covers closed.

Another object of this invention is to provide a molded polymeric container with a double cover having a combined overcenter closure action and special end camming and latching features in the overcenter position to result in a particularly effective closure function with a minimum of material.

The container end panels are specially configurated and arranged with a downwardly inwardly sloping camming surface terminating in a latching recess both cooperative with special latching protrusions on the cover member end panels. The protrusions, which are preferably flanges on the lower edges of the cover end panels, slope downwardly toward the center of the carton, as do the recesses.

These and other constructional features are set forth in detail in the following description which is to be read in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary perspective view of one end of the novel container;

FIG. 2 is a fragmentary perspective view of the end of the container in FIG. 1, showing one of the two cooperative cover members in a partially opened position;

FIG. 3 is an end elevational view of the container;

FIG. 4 is a fragmentary sectional view taken on plane IV-- IV of FIG. 1, but showing the cover members in the open posi tion;

FIG. 5 is a fragmentary, partially sectioned, elevational view taken on plane V-V of FIG. 4;

FIG. 6 is a fragmentary perspective view showing the inner portions of one end of the carton, with one cover member being open and the other cover member being closed; and

FIG. 7 is a side elevational view of the carton.

DESCRIPTION OF THE PREFERRED EMBODIMENT The container 10 is primarily intended and constructed for containing fragile articles, particularly eggs. It is generally elongated in configuration, and composed of a bottom member 12 and a pair of cover members 14 and 14. It is molded of a polymeric material, preferably a foam-type polymer such as polystyrene, polyvinyl, or other suitable equivalents. The unit is molded as one integral piece, with cover members 14 and 14' being respectively hingedly connected to bottom member 12 by integral hinges l6 and 16' along the upper outer edges of the bottom member.

Bottom member 12 is provided with panels 18 and I8 and upstanding central panels 20 and 20 as well as outer wall panels 22 and 22 cooperatively interjoined and configurated to form a plurality, here two, of rows of configurated receiving cups 24 and 24. These particular receiving cups may vary somewhat in configuration as is desired. Each cup is separated from the adjacent cup in its row by respective transverse panel members 26 and 26'.

Cover members 14 and 14' each have respective top elongated panels 30 and 30', outer side panels 32 and 32', inner side panels 34', and a pair of end panels 36 and 36'.

The construction of both ends of the carton or container is the same, including the construction of the bottom member and the construction of the cover members. Therefore, for purposes of convenience, only one end will be described in detail.

Cover members 14 and 14' cooperatively form an overcenter closing action which, in combination with a special latching arrangement between the cover members and bottom member 12, provide an extremely effective closure feature when the cover members are moved from their first open position to their second closed and latched position. When in this closed position, portions of the cover members protrude below the general plane of hinges 16 and 16. Specifically, the lower edge portions of cover inner panels 34 and 34' protrude below this horizontal plane containing the hinges, as well as the lower portions of cover end panels 36 and 36'. The lower edges of panels 36 and 36 are at an acute angle to inner panels 34 and 34. Along these lower edges are protruding flanges 40 and 40' which project outwardly of the container to cooperate with special camming surface area 44 on bottom member 12 and cooperative with latching recesses 46 and 46 along the lower edge of camming surface 44. These flange protrusions are also at an acute angle to the inner panels 34 and 34 and normally are at an angle with respect to upper panels 30 and 30', rather than being parallel to them.

When covers 14 and 14' are in the closed position, panels 34 and 34' lie in facing abutment with each other. The distance between hinges l6 and 16', transversely of the carton, is less than the combined length of protrusions 40 and 40, i.e., the combined distances from the lower edge of inner panels 34 and 34' to hinges 16 and 16', i.e., the combined length of the lower edges or lower edge zones of cover member end panels 36 and 36'. Hence, when opening or closing the cover members, they must pass through an overcenter type action when flanges or protrusions 40 and 40' lie in the plane of the hinges, at which point maximum resilient deflection of the container construction has occurred against the inherent bias of the container material. This deflection begins when the cover members are several degrees either side of this position of most deflection, i.e., toward open or closed positions. The bias created by this deflection tends to hold the cover in open or closed position. Therefore, tendency of cover members 14 and 14' to open from the closed position is resisted by the inherent resilient resistance of the container materials to this deflection. Likewise, when the container cover members are shifted to closed position, manual force must be applied to force the cover members through this abutting position between the lower portions of the inner panels 34 and 34 to force them through this resilient deflected position.

Camming surface 44 slopes downwardly and inwardly of the container. Further, the vertical height of camming surface 44 is greatest at the centerline or center plane of the carton, i.e., midway between the side edges, and tapers to a negligible height at the edges of the carton, specifically adjacent the hinge centerlines of hinges l6 and 16, adjacent the upper outer edges of container bottom 12 and the lower outer edges of container cover members 14 and 14'. Further, camming surface 44 has its greatest breadth dimension, measured lengthwise of the cartons, at the centerline or centerplane of the container, and tapers to a negligible breadth at the side edges of the canon. Camming surface 44 therefore normally has a compound curvature. The lower edge portions of camming surface 44 terminate abruptly into outwardly extending latching recesses 46 and 46 in contrast to the gradual slope of the camming surface 44 itself. Recesses 46 and 46 are configurated to snugly receive flange protrusions 40 and 40' respectively. These recesses preferably not only taper downwardly inwardly from the hinge line plane at the carton edge to the position displaced downwardly from the plane of the hinges, but also taper inwardly in the dimension of the length of the carton, corresponding to the preferred inward taper (with respect to the length of the carton) of flanges 40 and 40' and end panels 36 and 36'.

Hence, when closure of cover members 14 and 14' occurs, the outer edges of flange protrusions 40 and 40' engage the outer portions of camming surface 44 first, with progressive camming action occurring along the length of flanges 40 and 40' toward the center of the carton. At the same time, the cover members are forced through the overcenter resilient biasing action. Therefore, not only does resilient deflection occur of the container materials in a dimension transverse to the container, but also lengthwise of the container, with part of this deflection occurring in the cover members and part occurring in the bottom member. Because of the unique construction, resilient deflection of the carton materials actually occurs in three dimensions simultaneously to apply a resilient bias tending to snap" the cover members into closed position to provide a very effective latching action. Yet, when latched, the members are in a generally relaxed condition so that no undue continued stress is placed upon the container materials.

Release of the cover members to open them is effected by pressing inwardly on end panels 36 and 36' of the cover members, with or without outward manual force being directly applied to camming surface 44, followed by lifting action on the cover members to force them through the overcenter condition to the relaxed open position illustrated in FIG. 4.

It will be readily observed by those skilled in this field that this novel construction is not only effective from a closure standpoint, but also requires no extra materials to significantly increase the cost of the carton construction. Furthermore, it can be readily formed on forming equipment on a mass production basis.

Additional advantages inherent in this construction may occur to those skilled in this field upon studying this disclosure. It is also conceivable that the construction may be modified as to certain details without departing from the concept presented.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A molded container for fragile articles such as eggs, having to latch body member with a pair of sides with opposite upper side edges, and a pair of ends, said body member also having portions defining a plurality of rows of cups, a pair of cover members hinged on integral hinges to said body member at said side edges, each cover member movable from a first position uncovering respective of said rows to a second position covering such; the improvement comprising: said cover members having e nd panels with lower edge zones the comblned length of which rs greater than the distance between said hinges on opposite side edges of said body member, with said body member ends and cover member end panels being configurated to allow overcenter movement of said cover members in their second position; latching means between said cover members and said body member arranged to latch said cover members to said body member in said overcenter position; said cover members each including inside panels arranged to abut each other when said cover members are in said second position, said hinges being generally in the same plane, and said lower edges of said cover member end panels being at an acute angle to said inside cover member panels to pass through said plane as said cover members are shifted from said first position to said second position; said cover member end panel lower edges including first parts of said latching means, and said body member ends having cooperative second parts of said latching means displaced out of said hinge plane to latch to said cover means parts in said cover member second position; camming means between said body member ends and the respective cover member end panels to deflect the polymeric panels into a condition of inherent resilient bias with movement of said cover members from said first position toward said second position to cause a resilient latch of said latching means; said first parts of said latching means including protrusion means, said second parts of said latching means including recess means to receive said protrusion means, and said camming means including a sloping surface adjacent said recess means and engageable by said protrusion means prior to latching to cause a biased movement into latching condition.

2. The container in claim 1 wherein said camming surface has a substantial vertical height substantially midway between said side edges and tapers to a negligible height at said opposite-side edges.

3. The container in claim 2 wherein said camming surface has its greatest breadth substantially midway between said opposite-side edges.

4. A molded container for fragile articles such as eggs having a body member with a pair of sides with opposite upper side edges and a pair of ends, said body member also having portions defining a plurality of rows of cups, cover means hinged to the side edge of said body member and movable from a first row-uncovered position to a second row-covering position; the improvement comprising: a camming surface on said body member ends sloping generally inwardly and downwardly and terminating in latching recess means; and said cover means having end panels with latching protrusions on the lower edge portions thereof engageable first with said camming surfaces to cause a resilient deflection thereof and then with said recess means to latch therewith when said cover means is shifted from said first to said second position.

5. The container in claim 4 wherein said cover means is a pair of cover members hinged on opposite-side edges of said body member, said hinges being generally in the same plane and said recesses slanting downwardly generally from said plane to a position spaced from said plane.

6. The container in claim 5 wherein said cover members inelude inner panels which lie in abutment and said latching protrusions are received in said slanting recesses when said cover members are in their closed position.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 625 .1413 Dated December 7 l971 Inventor(s) Roger L. Medendorp It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Col. 1, lines (0J1, change "overcenter" to -members---;

Col. 2 line 28, before "34" insert 3 4 and;

Col. 3, Claim 1, line 66, after "having" add --a-- and delete "to latch".

Signed and sealed this 29th day of August 1972.

(SEAL) Attest:

EDWARD NLFLETCHERJR. ROBERT GO'ITSCHALK Atte sting Officer Commissionerof Patents DRM PC -1050 {Ill- 4Q) USCOMM-DC 6037 7'69 u s unvnmmm rnlnrmn mnu' In: rwnrlu

Claims (6)

1. A molded container for fragile articles such as eggs, having to latch body member with a pair of sides with opposite upper side edges, and a pair of ends, said body member also having portions defining a plurality of rows of cups, a pair of cover members hinged on integral hinges to said body member at said side edges, each cover member movable from a first position uncovering respective of said rows to a second position covering such; the improvement comprising: said cover members having end panels with lower edge zones the combined length of which is greater than the distance between said hinges on opposite side edges of said body member, with said body member ends and cover member end panels being configurated to allow overcenter movement of said cover members in their second position; latching means between said cover members and said body member arranged to latch said cover members to said body member in said overcenter position; said cover members each including inside panels arranged to abut each other when said cover members are in said second position, said hinges being generally in the same plane, and said lower edges of said cover member end panels being at an acute angle to said inside cover member panels to pass through said plane as said cover members are shifted from said first position to said second position; said cover member end panel lower edges including first parts of said latching means, and said body member ends having cooperative second parts of said latching means displaced out of said hinge plane to latch to said cover means parts in said cover member second position; camming means between said body member ends and the respective cover member end panels to deflect the polymeric panels into a condition of inherent resilient bias with movement of said cover members from said first position toward said second position to cause a resilient latch of said latching means; said first parts of said latching means including protrusion means, said second parts of said latching means including recess means to receive said protrusion means, and said camming means including a sloping surface adjacent said recess means and engageable by said protrusion means prior to latching to cause a biased movement into latching condition.

2. The container in claim 1 wherein said camming surface has a substantial vertical height substantially midway between said side edges and tapers to a negligible height at said opposite-side edges.

3. The container in claim 2 wherein said camming surface has its greatest breadth substantially midway between said opposite-side edges.

4. A molded container for fragile articles such as eggs having a body member with a pair of sides with opposite upper side edges and a pair of ends, said body member also having portions defining a plurality of rows of cups, cover means hinged to the side edge of said body member and movable from a first row-uncovered position to a second row-covering position; the improvement comprising: a camming surface on said body member ends sloping generally inwardly and downwardly and terminating in latching recess means; and said cover means having end panels with latching protrusions on the lower edge portions thereof engageable first with said camming surfaces to cause a resilient deflection thereof and Then with said recess means to latch therewith when said cover means is shifted from said first to said second position.

5. The container in claim 4 wherein said cover means is a pair of cover members hinged on opposite-side edges of said body member, said hinges being generally in the same plane and said recesses slanting downwardly generally from said plane to a position spaced from said plane.

6. The container in claim 5 wherein said cover members include inner panels which lie in abutment and said latching protrusions are received in said slanting recesses when said cover members are in their closed position.

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