Carton with automatic lock

• US 4,516,718 A
• Filed: 09/20/1983
• Issued: 05/14/1985
• Est. Priority Date: 09/20/1983
• Status: Expired due to Term

• Current Assignee: Meadwestvaco (WestRock Company)
• Original Assignee: Westvaco Corporation (Meadwestvaco Corporation)
• Inventors: Forbes, Hampton E. Jr.
• Primary Examiner(s): MOY, JOSEPH MAN
• Application Number:
  US06/534,069
• Time in Patent Office: 602 Days
• Field of Search: 229/33, 229/39 R, 229/43, 229/44 R, 229/45 R
• US Class Current: 229/146
• CPC Class Codes: B65D 5/6626 formed by folding extensions of a side panel of a container body formed by erecting a "cross-like" blank
• CPC Class Codes: B65D 5/68 Telescope flanged lids

Abstract

A carton for food products or the like comprises a combination lid and tray with an automatic locking means for securing the lid and tray when the carton is closed. The automatic locking means consists of one or more locking tongues integral with the tray component which engage one or more locking slots formed in the lid component. The locking tongues include locking posts and shoulders which become engaged behind locking tabs formed by the locking slot when the carton is closed. The locking tongues remain exposed above the top of the lid when the carton is closed where they may be readily removed or released to open the carton.

Claims

1. A carton with an automatic locking closure means comprising:

(a) A tray member including side walls extending upwardly from a bottom panel about score lines;

(b) a lid member including side walls extending downwardly from a top panel about score lines;

(c) at least one male locking element connected to and extending upwardly from the upper edge of one of the side walls of the tray member in the same general plane of the side wall as an integral extension thereof, said locking element including a first shoulder portion which extends above the top edge of the side wall, a locking post integral with said shoulder portion which extends above the shoulder portion, and a tongue member integral with said locking post which extends above the locking post, said shoulder portion having a greater width than both said locking post and tongue member and said tongue member having a greater width than said locking post, said tongue member including a leading edge which tapers rearwardly to a pair of opposed shoulders which are formed from the material between said locking post and said first shoulder portion;

(d) at least one cooperating female locking slot located generally along the score line connecting the lid top panel to an adjacent side wall, said slot being in the form of a continuous cut line comprising a central segment located in the top panel portion of the lid closely adjacent to said score line and at the ends of said central segment a pair of terminal segments located partly in the top panel and partly in the adjacent side wall to provide locking tabs which automatically engage the locking shoulders of said tongue element when the lid and tray are brought together to form the carton.

2. The carton of claim 1 wherein the central segment of said locking slot provides an upstanding portion of the adjacent side wall which engages the tongue member to guide it into the locking slot.

3. The carton of claim 2 wherein the outer edges of said first shoulder portion extend through the locking slot at its terminal segments thereby wedging the locking tabs of said locking slot beneath the shoulders of said tongue member to produce the automatic locking engagement of said tongue member with said locking slot.

4. The carton of claim 3 wherein the side walls of both said tray member and lid member taper outwardly to provide a guide for orienting the engagement of said tongue member with said locking slot.

5. The carton of claim 4 wherein means is provided for releasing the locking engagement of said tongue member and locking slot for opening said carton.

6. The carton of claim 5 wherein the release means comprises a perforated line on the tongue member in the region of said locking post which permits said tongue member to be removed for opening the carton.

7. The carton of claim 5 wherein the release means comprises a pair of perforated lines in the adjacent side wall of said lid member located beneath said tongue member and separated from one another by a distance substantially equal to the nominal width of said locking post which permits the removal of a portion of the side wall in the vicinity of the locking slot to release the tongue member for opening the carton.

8. The carton of claim 5 wherein the lid member and tray member are cut and scored from a single blank of paperboard or the like.

9. The carton of claim 5 wherein the lid member and tray member are cut and scored from separate blanks of paperboard.

10. A carton with an automatic locking closure means cut and scored from a blank of paperboard or the like comprising a tray component including side, front and rear walls each having the shape of a trapezoid foldably attached to a central bottom panel along the minor base portions thereof and a lid component including side, front and rear walls each having the shape of a trapezoid foldably attached to a central top panel along the minor base portions thereof, glue flaps foldably attached to an edge of each side, front and rear wall and adhered to an adjacent side, front or rear wall to form tray and lid components of generally truncated pyramid configurations, said tray and lid components being joined along a fold line common to their rear walls, said locking means further comprising:

(a) at least one male locking element extending upwardly from the top edge of the front wall of the tray member in the same general plane of the front wall as an integral extension thereof, said locking element including a first shoulder portion which extends above the top edge of said front wall, a locking post integral with said shoulder portion which extends above the shoulder portion, and a tongue member integral with said locking post which extends above the locking post, said shoulder portion having a greater width than both said locking post and tongue member and said tongue member having a greater width than said locking post, said tongue member including a leading edge which tapers rearwardly to a pair of opposed shoulders which are formed from the carton material located between said locking post and said first shoulder portion; and

,

(b) at least one cooperating female locking slot located generally along the score line connecting the lid top panel to its front wall, said slot being in the form of a continuous cut line comprising a central segment lying in the top panel portion of the lid closely adjacent to said score line and a pair of terminal segments lying partly in the top panel and partly in the front wall to produce a tongue receiving slot area formed partially in the top panel and partially in the front wall when the lid component is formed, wherein the central segment provides an upstanding portion of the front wall for guiding the tongue member into that part of the slot area formed in the top panel, and said terminal segments provide locking tabs formed from the front wall which wedge the shoulder portions of the tongue member through those portions of the slot area formed in the front wall to provide an effective, automatic locking engagement of the tongue and slot when the tongue member is fully inserted in the locking slot.

11. The carton of claim 10 including means for opening the carton, said means comprising a pair of spaced perforated lines in the front wall of the lid component located beneath the locking slot whereby a portion of the front wall may be removed to release the locking elements.

12. A carton with an automatic locking closure means comprising a tray component cut and scored from a blank of paperboard or the like, said tray component including a plurality of side walls each having the shape of a trapezoid foldably attached to a central bottom panel along the minor base portions thereof and a lid component cut and scored from a blank of paperboard or the like, said lid component including a plurality of side walls each having the shape of a trapezoid foldably attached to a central top panel along the minor base portions thereof, glue flaps foldably attached to an edge of each of the side walls of each component and adhered to an adjacent side wall to form components of generally truncated pyramid configuration, said locking means further comprising:

(a) at least one pair of male locking elements extending upwardly from the top edge of two opposed side walls of said tray component in the same general planes as the side walls as integral extensions thereof, said locking elements including first shoulder portions which extend above the top edges of each side wall by a nominal amount, locking posts integral with each shoulder portion which extend above the shoulder portions, and tongue members integral with each locking post which extend above the locking posts, said shoulder portions having a greater width than both said locking posts and said tongue members, and said tongue members having a greater width than said locking posts, said tongue members each including a leading edge which tapers rearwardly to a pair of opposed shoulders which are formed from the carton material located between said locking post and said first shoulder portion; and

,

(b) at least one pair of cooperating female locking slots located generally along the score lines connecting the top panel to two opposed side walls of said lid component, said slots being in the form of continuous cut lines comprising central segments lying in the top panel portion of the lid closely adjacent to said score lines and pairs of terminal segments lying partly in the top panel and partly in the side walls to produce tongue receiving slot areas formed partially in the top panel and partially in the side walls when the lid component is formed, wherein the central segments provide upstanding portions of the side walls for guiding the tongue members into those parts of the slot areas formed in the top panel, and said paired terminal segments provide locking tabs formed from the side walls which wedge the shoulder portions of the tongue members through those portions of the slot areas formed in the side walls to provide an effective, automatic locking engagement of the tongues and slots when the tongue members are fully inserted in the locking slots.

13. The carton of claim 12 including means for opening the carton, said means comprising perforated lines in each tongue member in the region of the locking posts whereby the tongue members may be removed to release the locking elements.