Neck For Widemouth Jar And Cap Therefor

Abstract

A widemouth jar of plastic or glass of the type used for peanut butter has an exterior neck finish comprising two circumferential, vertically spaced buttressed beads, the lower being of greater diameter than the upper. The plastic cap which fits on the neck has a flattop disk with a peripheral skirt, the interior of which is formed with two circumferential beads dimensioned to engage immediately under the radial flanks of the beads of the neck. The wall of the skirt is weakened immediately above the lower cap bead in a circumferential internal groove which connects with a downward slanted internal groove extending to the bottom of the skirt. A finger grip tab depends from the bottom of the skirt to one side of the slanted groove. This application is an improvement upon U.S. Pat. No. 3,338,446 patented Aug. 29, 1967. However, the present invention is particularly suited to widemouth (e.g. 120 mm.) jars of plastic suitable for peanut butter and other substances which have heretofore been packed in glass jars closed with metal screw caps.

Description

When widemouth jars of this general type are subjected to forces which tend to deform them such as occur during transportation or when the jar is dropped, the means tending to retain the cap on the jar neck tends to fail between the retaining means spring apart. A principal feature of the present invention is the fact that the jar neck and cap have cooperating retaining means which hold the parts in place despite severe stresses tending to dislodge the same.

The plastic cap has a depending skirt weakened with a circumferential score line intermediate two cooperating retaining means on the cap and jar neck so that the portion of the skirt below the score line may be torn off. Before the bottom of the skirt is torn away, it provides means to prevent tampering with the contents of the jar and also tending to retain the cap in place. After the skirt has been torn, the portion above the score line constitutes a reclosure cap which may be used repeatedly until the contents of the jar are exhausted.

It is, therefore, an important feature of the invention to provide a closure wherein the seal must be obviously broken before access to the container is afforded. This is an aid in detection of tampering. On the other hand, the contour of the cap and jar neck facilitate installation of the cap on the neck but make it impossible to remove the cap without tearing a portion of the skirt. Another feature of the invention is the fact that the cap may be installed on the jar very easily. This makes possible the use of production line closing techniques.

Another feature of the invention is the fact that the cap seals on the neck in such manner that a tight seal is effected which prevents leakage of the contents and also prevents ingress of contaminants.

Other objects of the present invention will become apparent upon reading the following specification and referring to the accompanying drawings in which similar characters of reference represent corresponding parts in each of the several views.

In the drawings:

FIG. 1 is a fragmentary elevational view of a jar and cap in accordance with the present invention.

FIG. 2 is a top plan thereof.

FIG. 3 is a view similar to FIG. 1 showing the bottom of the skirt partially torn away.

FIG. 4 is an enlarged sectional view through a portion of the jar neck and cap in assembled position, partially broken away to conserve space.

FIG. 5 is a fragmentary sectional view showing the cap prior to installation on the jar.

Jar 11 and cap 12 may both be made of a plastic material such as polyethylene or polystyrene, or other suitable material which is slightly deformable under stress. This invention has particular application in the closure of widemouth jars 11 such as jars of 120 mm. in diameter and upward. Because of the difficulty in effecting a seal, jars of this type have conventionally been made of glass and have been sealed with a metal closure. The present invention may be used either with a plastic jar or a glass jar as desired.

The neck 13 of such jar has a horizontal lip 14. Below lip 14 the neck wall is substantially uniform in thickness. The interior of the neck 13 proceeding from top to bottom has a short cylindrical portion 16, a narrow concave portion 17, an outwardly downwardly slanted conical portion 18, a second concave portion 19, an elongated substantially cylindrical portion 21 and an outwardly bowed portion 22. The exterior of neck 13, commencing from top lip 14 has a short cylindrical portion 26 of a length approximately equal to that of cylindrical portion 16. Below portion 16 is a buttress bead formed by an outwardly downwardly slanted flank 27 which terminates abruptly in an inward directed horizontal flank 28 at an elevation approximately equal to that of concave portion 17 of the interior. Below flank 28 is another outwardly downwardly slanted flank 29 which terminates in an abrupt inward directed horizontal flank 31 to form a lower buttress head. Flank 31 has a greater maximum diameter than flank 27. Flank 31 is below the elevation of concave portion 19. Below flank 31 is an outwardly downwardly slanted portion 32 which terminates in an elongated cylindrical surface 33 opposite surface 21 and this terminates in turn in an outwardly directed portion 34 opposite portion 22. The exterior of the neck 13 is of considerable importance in the present invention. It will be noted that the flanks 27,28 form in effect a buttress shaped bead and that the flanks 29,31 form a similar buttress-shaped bead. The outside maximum diameter of the flank 29 is slightly greater than that of flank 27. In other words, the upper buttress bead is smaller than the lower.

Directing attention now to cap 12, the top disk 36 is circular and has a skirt 37 depending from the periphery thereof. Skirt 37 is substantially cylindrical on its exterior but the interior thereof is of irregular shape. Proceeding from the top of the interior of skirt 38 there is a short cylindrical inner surface 38 which matches in length cylindrical portion 26 and the disk merges into an outwardly-downwardly slanted surface 39 which terminates at the elevation of flank 28 and has below it an internal bead 41 which is substantially semicircular in cross section and in the assembled position of the cap and jar neck immediately under flank 28. Below bead 41 there is a cylindrical surface 42 which has indented therein an approximately rectangular cross section groove 43. The lower edge of groove 43 is opposite flank 31. Below groove 43 is a bead 44 which in the assembled position of cap and jar, nests immediately below flank 31. Bead 44 is of a semicircular cross section. Below bead 44 is a cylindrical portion 46 which extends down to the bottom edge of skirt 37. Spaced inwardly of skirt 37 depending from the bottom of disk 14 is an internal skirt 47 which is cylindrical on its inner surface and on its outer surface rests against surface 16 with a tight fit. As shown in FIG. 5, the outer surface 49 of skirt 47 and the skirt surface 38 of skirt 37 converge upwardly and are deformed by lip 14 when the parts are assembled. To facilitate installation of the cap, the lower outer edge of skirt 47 is beveled as indicated by reference numeral 48.

The groove 43 is a weakening of the wall thickness of the skirt 37 and extends circumferentially around said skirt. The thickness of the material at the situs of groove 43 is such that the cap 12 does not rupture unintentionally but is easily torn. At one location, a downward slanted starting groove 50 extends to the bottom edge of skirt 37 (see especially FIG. 1) and to one side of the terminus of groove 50 is a tab 51 which is conveniently gripped by the fingers. Above groove 43 immediately opposite groove 50 is a projection 52 which may be gripped by the fingers to remove the upper portion of cap 12 when required as hereinafter explained. The projection 52 serves as a reinforcement to prevent the user from unintentionally tearing the cap along the slanted line 50 above the level of groove 43.

In the use of the device, after the jar 11 has been filled with a product, the cap 12 is installed. Automatic machinery may be used for this purpose but it will suffice to explain a manual installation. The skirt 37 is slipped on outside neck 13 and a downward pressure is applied. As slanted surface 48 guides the lip 14 between skirts 37 and 47 and as downward pressure is continued, the bead 41 slides over the slanted flank 27 and the bead 44 slides over the slanted flank 29 until beads 41 and 44 snap under the flanks 28 and 31, respectively. The flexible nature of the plastic material of which the cap and jar are fabricated, permits this temporary deformation of the parts. Thus assembled, the jar is sealed very tightly since the lip 14 is jammed between skirts 37 and 47 and the skirt 37 fits rather tightly against the outside of neck 13. It is impossible to remove the cap 12 while the skirt 37 is intact. It will be understood that jars of this type are subjected to considerable stress by handling in transportation or they may be dropped or otherwise crushed. This stress causes the jar 11 and also the cap 12 to be deformed somewhat but since the beads 41 and 44 are snapped in place under the buttress surfaces which have been described it is practically impossible to remove the cap.

When the consumer wishes to open the jar, he grips the tab 51 and pulls upwardly along score line 50 and then along score line 43. FIG. 3 shows a partial completion of the opening operation. The tab 51 is pulled all the way around the jar 11 which completely severs the skirt at the level of groove 43. The portion of cap 12 above the level of groove 43 (or bead 44) comprises a reclosure cap for the jar 11. To get access to the contents, the user pries upward on projection 52 using the fingers or a tool and this causes the bead 41 to snap out of position below flank 28. This operation is possible when there is only a single bead 41 in position. When the skirt 37 is intact before it is torn along groove 43, it is impossible to dislodge both the bead 41 and bead 44. The closure portion of the cap 12 may be replaced by pushing downwardly on disk 36.

Bead 41 snaps under flanks 28. The closure may be performed as many times as desired.

Claims

What I claim is:

1. In combination, a thin-walled container neck formed with an external, circumferential first upper bead spaced downward from the upper end of said neck and an external, circumferential first lower bead spaced downward from said upper bead, and a cylindrical outer surface below said lower bead, said upper bead being buttress-shaped and having a downward-outward slanted first conical flank and a substantially radial first bottom flank at the lower end of said first conical flank, said lower bead being buttress-shaped and having a downward-outward slanted second conical flank originating at about the level of said first bottom flank and a substantially radial second bottom flank at the lower end of said second conical flank; and a deformable plastic cap formed with a central top disk and a substantially cylindrical, thin-walled outer skirt depending from the periphery of said disk, said outer skirt scored and weakened in a circumferential first groove opposite the lower edge of said first conical flank and also in a slanted second groove joining said first groove and extending down to the bottom edge of said outer skirt, and an integral tab extending below said bottom edge adjacent the lower end of said second groove, an internal circumferential upper second bead of approximately semicircular cross section positioned immediately below said first bottom flank, an internal circumferential lower second bead of approximately semicircular cross section positioned immediately below said first groove and said second bottom flank; said cap and neck interfitting in assembled position with the upper edge of said neck tight against the underside of said disk and the inside of said outer skirt fitting tight around the outside of said neck.

2. The combination of claim 1 in which said cap is formed with a short cylindrical inner skirt depending from said disk spaced inward from said outer skirt, the upper end of said neck wedged between said skirts to form a tight seal.

3. A deformable, plastic cap for a thin-walled container neck formed with an external, circumferential first upper bead spaced downward from the upper end of said neck and an external, circumferential first lower bead spaced downward from said upper bead, and a cylindrical outer surface below said lower bead, said upper bead being buttress-shaped and having a downward-outward slanted first conical flank and a substantially radial first bottom flank at the lower end of said first conical flank, said lower bead being buttress-shaped and having a downward-outward slanted second conical flank originating at about the level of said first bottom flank and a substantially radial second bottom flank at the lower end of said second conical flank; said cap having a central top disk and a substantially cylindrical, thin-walled outer skirt depending from the periphery of said disk, said outer skirt scored and weakened in a circumferential first groove opposite the lower edge of said first conical flank and also in a slanted second groove joining said first groove and extending down to the bottom edge of said outer skirt, and an integral tab extending below said bottom edge adjacent to the lower end of said second groove, an internal circumferential upper second bead of approximately semicircular cross section positioned immediately below said first bottom flank, an internal circumferential lower second bead of approximately semicircular cross section positioned immediately below said first groove and said second bottom flank.

4. A cap according to claim 3 which further comprises a short, cylindrical inner skirt depending from said disk spaced inward from said outer skirt.