US 3823848 A
A sealing plug for insertion in the tap hole of a container, comprising a cylindrical body having a uniform diameter portion, said body having means extending radially outwardly on its upper end for manual gripping for withdrawal of the plug from the hole and for preventing pushing of the plug from the hole into the container, and having means on its lower end for preventing ejection of the plug from the hole without hindering the insertion of the plug into the hole. The uniform diameter body of the plug fits snugly within and in sealing contact with a collar defining the hole throughout its length while a curved annular surface located radially inwardly of the gripping means between the gripping means and the cylindrical body bears radially outwardly and also downwardly on the collar to enhance dependable sealing between plug and container.
Claims available in
Description (OCR text may contain errors)
United States Patent 1191 Schuster ,et al.
1111 3,823,848 July 16, 1974 SEALING PLUG FOR A CONTAINER Primary Examiner-Robert B. Reeves  lnvemors' 23:32:23; g i z sg l i g gh Assistant Examiner-David A, Scherbel both of CD16. Attorney, Agent, or Firm-Bertha L. MacGregor  Assignee: Adolph Coors Company, Golden,  ABSTRACT Colo. A sealing plug for insertion 1n the tap hole of a con- Flledi g- 1972 tainer, comprising a cylindrical body having a uniform [211 App] No 284 661 diameter portion, said body having means extending radially outwardly on its upper end for manual gripping for withdrawal of the plug from the hole and for  US. Cl. 222/82, ZZZ/400.7 preventing pushing of the plug from the hole into the  Int. Cl B65d 83/00 container, and having means on its lower end for pre-  Field Of Search 222/563, 400.7, 82; venting ejection of the plug from the hole without hin- 217/1 11 l dering the insertion of the plug into the hole. The uniform diameter body of the plug fits snugly within and References Cited in sealing contact with a collar defining the hole UNITED STATES PATENTS throughout its length while a curved annular surface 2 323 904 7/1943 Geertsen 222/563 located radially inwardly of the gripping means 219211724 1/1960 Whitney 222/563 x twoenithe g pp means and the Cylindrical y 3,410,456 12/1968 Johnson, Jr. et al 222/4007 x bears radially outwardly and also downwardly on the 3,545,475 12/l970 Johnson, Jr. et al ZZZ/400.7 X collar to enhance dependable sealing between plug FOREIGN PATENTS OR APPLICATIONS and FP 817,097 10/1951 Germany 222/563 Claims, 4 Drawing Figures L 1 32 7 7 T 33 33 P 34 34 I3 I T 2/ l2 /3 I 1 1 1 SEALING PLUG FOR A CONTAINER This invention relates to a sealing plug designed to closely fit into and to seal a hole in a container holding pressurized contents, and more particularly to a sealing plug through which a tap may be inserted into the container for the purpose of withdrawing fluid from the container.
The main object of the invention is to provide an improved sealing plug which efficiently seals the tap hole in a container and which includes means for preventing pushing of the plug into the container when the tap is being forced therethrough, and for facilitating removal of the plug from the tap hole when the containeris empty.
This invention has been shown as embodied in a sealing plug which employs a resiliently yieldable membrane extending across the bottom of a bore in the plug to establish a seal between the bore and interior of the container, said membrane being puncturable by the end of a tap tool, and a flapper formed integrally with and hinged to the inner end of the plug and adapted to be urged into face to-face engagement with the inner end of the plug to close said bore after removal of the tap from the container, described in the Johnson et al. U.S. Pat. No. 3,410,456. However, our invention may be embodied in sealing'plugs which do not utilize the thin membrane and flapper arrangement which is the subject of said patent.
Prior art sealing plugs, as exemplified by the aforementioned construction, designed to be knocked out of v the tap hole to fall into the container when empty, have proven unsatisfactory in use because such plugs can be unintentionally pushed into the container when the tap tool is-being forced through the sealing plug bore and thin membrane into the container. In order to prevent unintentional pushing of the plug out of its tap hole into the container, and to provide means for manually lifting the plug out of the hole and removal from the container, the plug of this invention comprises a cylindrical body designed to have a close fit in and sealing contact with the entire length of the collar which defines the tap hole in the container, together with flange means at its outer end for manual gripping of the plug for removal and also for preventing pushing of the plug downwardly in the tap hole, coupled with means on the inner end of the plug for preventing unintentional ejection of the plug but permitting removal thereof when the operator employs the manual gripping means for withdrawal purposes.
In the drawings:
FIG. 1 is an elevational view, partly broken away and in section, of a container having a tap hole adapted to be closed by a sealing plug embodying our invention.
plug when fully seated. in the container tap hole.
In the embodiment of the invention shown in the drawings, a container such as a beer keg, for example, is provided with a head 11 having a tap hole 12 in defined by a collar 13 provided with a flange 14 extending outwardly around the upper edge of the collar. The tap hole 12 is adapted to receive a conventionaltap tool (not shown) usually comprising a telescoping gas tube and a draw tube within the gas tube, as is well known in the art, said tap tool being attached to the flange 14 to extend downwardly through a sealing plug into the container.
The tap hole 12 is sealed by the sealing plug of this invention, which comprises a cylindrical body 21 molded of rubber or other resilient and yieldable material, having a central bore 22 initially closed at its bottom by a thin wall or membrane 23 puncturable by the tap tool when inserted into the bore 22 and forced through the wall 23. Beneath the wall 23 and integral with the lower end of the plug body 21 in a segment of its periphery is a flap 24. The integral connection between the plug and flap 24 serves as a hinge 25 which permits the flap to close the opening made by insertion of the tap tool and puncturing of the wall 23, as fully described in the aforementioned U.S. Pat. No. 3,410,456. 'As hereinabove stated, the described flap arrangement is not an essential element of the invention of this application. I
The outer diameter of the sealing plug. cylindrical body 21 is uniform in its entire area designed to fit snugly in contact with the tap hole collar 13 as well as inner portions of the flange l4 and depressed head portion 11 which define the tap hole 12, as shown in FIG. 4.
Above the uniform diameter portion'of the body 21,
the plug 20 is provided with a peripheral annular flange adjacent the top edge 31, extending radially outwardly between the horizontal surfaces 31 and 32 to form gripping means spaced from the tap hole collar flange 14 by the space located outwardly of the cut back surface 33 above the annular curved surface 34 which limits the extent to which the plug body 21 can the depressed part 11' of the head 11, said hole being be inserted into the tap hole 12; said curved surface 34 also serving to bear radially and downwardly on the collar to provide additional sealing means between the plug and the collar 13.
Below the uniform diameter portion of the body 21 the plug is thickened radially between the bore 22 and the upwardly facing tapered shoulder 35 and the inwardly and downwardly tapered surface 36 which joins the plug bottom. The shoulder 35 prevents unintentional ejection of the plug and also prevents uninten tional withdrawal of the plug when the tap tool (not shown) is pulled upwardly out of the plug. The shoulder 35 and part of the tapered portion 36 are compressed when the plug is being inserted into the hole in the collar 13 as shown in FIG. 3, but spread radially automatically to engage the lower end of the collar when fully inserted as shown in FIG. 4.
The close contact between the uniform diameter body 21 and the entire length of the collar 13, as well as the sealing effect of the curved annular surface 34 bearing radially and downwardly on the upper inner surface formed by the junction of the collar. 13 and flange 14, produces a highly efiicient seal between the container and plug. The gripping means 30 conveniently spaced from the collar flange 14 by the space located outwardly of the cut back surface 33 serves the dual purpose of providing manual means for withdrawing the plug and for preventing unintentional pushing of the plug through the tap hole into the container. The
shoulder 35 serves to position the plug without interfer- 3 ing with its insertion in the tap hole and prevents unintentional ejection therefrom.
l. A sealing plug for insertion in a tap hole in a container defined by an internally smooth uniform diameter collar comprising:
I a. a hollow cylindrical body of resiliently yieldable elastomeric material having a uniform diameter portion as long as the overall length of the collar defining the tap hole, said uniform diameter portion fitting snugly within and sealingly contacting the entire inner surface of the collar,
b. manual gripping means above the uniform diameter portion thereof comprising an annular flange extending radially outwardly beyond the cylindrical body and the tap hole in the collar,
0. a cut back annular surface below the annular flange of greater diameter than the tap hole,
d. a curved annular surface extending downwardly and inwardly from the cut back surface to the uniform portion of the cylindrical body to bear radially and downwardly on the collar upon seating of the plug for providing an additional sealing'me'ans, said curved and cut back surfaces spacing the annular flange from the collar, and
e. means on the cylindrical body below the uniform diameter portion thereof cooperating with the inner end of the collar for preventing automatic ejection of the plug from the collar,
f. at least an upper portion of the curved annular surface being spaced from the uppermost surface of the collar when the plug is seated therein to space the cut back portion from the collar.
2. The sealing plugdefined by claim I, in which the curved annular surface bears radially and downwardly on the upper end of the collar.
3. The sealing plug defined by claim 1, in which the means on the cylindrical body below the uniform diameter portion thereof preventing automatic ejection of the plug comprises a downwardly and inwardly inclined surface having an upwardly facing tapered shoulder adjacent the uniform diameter portion of the body for bearing against the lower edge of the collar.
4. The sealing plug defined by claim 3, in which the means on the cylindrical body below the uniform diameter portion thereof preventing automatic ejection of the plug comprises a bottom wall which is puncturable by a tool insertable in the hollow body.