US 2953272 A
Description (OCR text may contain errors)
Sept. 20, 1960 G. v. MUMFORD ErA L CLOSURE CAPS FOR BOTTLES AND JARS Filed Feb. 27, 1958 l N V E N TO R5 620ml IZHU/YFOXD Y KALBHH WHITNEY United States Patent I 7 2,953,272 CLOSURE CAPS FOR BOTTLES AND JARS Filed Feb. 27, 19 's, Ser. No. 717,928 I 2 Claims. 01. 21541 The present invention relates to improvements in closure caps for bottlesand jars and hroraparticularly to venting means for. such caps. which will permit maintenance of safe internal pressures without leakage of the contents. v t 1 An object of our invention is the provision of simple and eifective means incorporated in a substar'ltiallyv allthermoplastic closure cap for bottles and jars which will permit escape of excess gas to the atmosphere and immediately thereafter efiect proper resealing of the container, irrespective of whether the latter stands alone or is at the bottom of a stack with the weight of the other containers applying top pressure to the closure cap.
Another object of our invention is the provision of a closure cap of the above character in which a relatively heavy semi-rigid ring and attaching flange or skirt element carry a flexible concavo-convex diaphragm, the latter formed with a sealing surface normally eflectively contacting a sealing surface on a bottle or jar, but capable of separation from the latter for venting excess gas from the bottle.
A further object of our invention is the provision of a closure cap formed of thermoplastic material and incorporating a concavo-convex central diaphragm having an annular marginal element normally sealingly engaging an internal sealing surface on a bottle or jar but momentarily separable from the latter under excessive internal gas pressure.
It is also an object of our invention to provide a novel arrangement of vent grooves and channels which, although permitting ready escape of excess gas pressure as explained above, will not under normal conditions allow communication between the atmosphere and interior of the container.
Other objects will be in part apparent and in part pointed out hereinafter.
In the drawings:
Fig. 1 is a fragmentary sectional view showing a closure cap incorporating our invention affixed to a container.
'Fig. 2 is a sectional view on a reduced scale taken substantially along the plane of line 2-2 of Fig. 1.
Fig. 3 is a fragmentary detail sectional view showing the venting position resulting from upward flexing of the diaphragm under internal pressure.
Fig. 4 is a fragmentary detail sectional view showing in full lines the diaphragm position indicated by dotted lines in Fig. 1.
Fig. 5 is a fragmentary sectional view of a slightly modified form of our invention.
In the illustrated embodiment of one form of our invention (Figs. 1-4) it is shown in conjunction with a glass jar or bottle provided with a reduced neck 11 defining a mouth 12. This neck is formed externally just below the rim 13 with an annular abutment 14 facing generally downward and capable of holding engagement with a portion of a closure cap 0 as will be apparent presently. An annular internal sealing surface 15 is formed substantially at the juncture of the rim 13 and "ice interior surface of the neck 11, the latter surface being tapered downwardly and inwardly if preferred.
The closure cap C which is formed of plastic or other elastomeric material comprises a relatively heavy semirigid ring 20 and an annular depending attaching skirt 21 of lesser diameter than the maximum diameter of the ring. Thus a continuous ledge 22 is provided for removal and application purposes. This attaching skirt is formed internally near its lower margin with a projection 23 which takes over and holdingly engages the aforementioned abutment 14.
A flexible concavo-convex diaphragm or disk 24 has its peripheral portions connected to the inner margin of the aforementioned ring 20. In that form of our invention shown in Figs. 1-4, a narrow annular flange 25 and an inwardly downwardly directed wall 26 interconnect v the diaphragm and ring. The inclined wall 26 is positioned to normally contact the sealing surface 15 throughout the length of the latter. It may flex upwardly to break such sealing contact when gas pressure internally of the container becomes excessive. Any such excess gas escapes to the atmosphere and thereupon the seal is reestablished.
Such escape of excess gas is made possible through the provision of an annular channel or groove 27 in the lower side of the closure cap substantially at the juncture of the inclined wall 26 and flange 25. This places the groove almost immediately over the upper, outer margin of the sealing surface 15.
A multiplicity of radial channels 28 extend along the lower side of said flange 25 and thence downward along the interior of the attaching skirt 21 opening through the lower margin of the latter. Because these vents are formed as channels in the relatively heavy portions of the closure cap it is apparent that the weight of stacked jars will not detrimentally affect the venting function of these channels. The thickness of the ring portion 20 is such that its upper surface lies in a horizontal plane well above that occupied by the diaphragm when the latter is flexed to its uppermost position. Thus there is no interference whatsoever to venting when necessary.
If desired, a price carrying disk 29 of any suitable material may be secured in place just above the diaphragm.
In Fig. 5 the closure cap generally is constructed as in the preferred form. However the diaphragm 24 carries a depending sealing flange or lip 30 which tapers downwardly and inwardly in the same fashion as the previously mentioned wall 26. The flexibility of both said wall 26 and the lip 30 as well as their position relative to the diaphragm and ring are such that effective sealing contact with the glass is provided irrespective of whether the closure cap is seated upon the container as in Fig. 3 or positioned as in Fig. 1.
It is believed apparent in view of the above that normally the closure cap effectively seals the container and with the building up of suflicient internal pressure the diaphragm flexes upwardly and vents the excess gas to the atmosphere through the annular groove 27 and radial vent channels 28. Normally expected top pressure cannot seal off the radial vent channels 28.
Modifications may be resorted to within the spirit and scope of the appended claims.
1. A venting-type closure cap for bottles and jars, said cap formed of a resilient thermoplastic material and comprising a relatively heavy semi-rigid ring, an attaching skirt depending from the ring at a point near its inner margin, a resilient generally concave-convex diaphragm positioned coaxially within the ring, an annular radial flange formed internally as an integral part of the ring and an annular inclined wall interconnecting adjacent marginal portions of the radial flange and diaphragm for sealing contact with the inner surface of a container mouth, said flange and attaching skirt formed internally with at least one vent-channel extending from the lower margin of the skirt upwardly and thence radially inward to the upper margin of the inclined wall.
2. In combination a container having an annular wall terminating in a circular mouth defining rim formed at its inner margin with a relatively narrow annular upwardly inclined sealing surface, said wall also provided with an external downwardly outwardly facing abutment for holding engagement with a closure cap, a venting-type closure cap formed at least in part of a resilient thermoplastic material and comprising a relatively heavy semi-rigid ring of greater diameter than said abutment, a resilient skirt depending from said ring, at a point radially inward from its periphery and telescoped over the abutment, an internal head on the skirt holdingly engaging the abutment, a resilient generally concavo-oonvex diaphragm Within and integral with said ring having its convex side facing axially outward and also having a portion immediately overlying the annular rim of the container, an annular inclined section connecting the last named portion and the diaphragm and normally in sealing contact with said inclined sealing surface of the container, said diaphragm radially outward of the inclined section and both the ring and atpassageways communicate with the interior of the container, the vent passageways including an annular downwazrdly facing channel immediately above the inner margin of the circular rim and generally radial grooves arranged about the closure cap and opening at one end into said a channel and at the other end through the lower margin of the attaching skirt.
References Cited in the file of this patent UNITED STATES PATENTS 1,694,851 Glass Dec. 11, 1928 2,325,309 De Swart July 27, 1943 2,693,892 Guinet Nov. 9, 1954 2,772,013 Stover Nov. 27, 1956 2,789,719 Wheaten lApr. 23, 1957 2,834,496 Boston et a1 May 13, 1958