US 2770382 A
Description (OCR text may contain errors)
W 13, 1956 v, n- 2,77%382 I CONTAINER Filed Aug. 15, 1952 2 Sheets-Sheet 1 INVENTOR VAUGHN L. RITTER ATTORNEY V. L... RITTEW CONTAINER 2 Sheets-Sheet 2 Filed Aug. 13, 1952.
INVENTOR VAUGHN L. RIT'TER ATTORNEY United States Patent CONTAINER Vaughn L. Ritter, Duukirkylnd yassignor to Armstrong. Cork, Company, Lancaster, Pa a corporation of Pennsylrania.
ApplicatiouAugust 13,"1952, Serial No. 304,089 6-,Claimsv (Cl: 215-31) This invention; relates toa thread finish for containers, and more particularly to a continuous thread having multiple bearing surfaces to prevent stresses in the walls of.
provide-a continuoushelical thread. on. the neck of the, container .and a corresponding;continuous helical thread,
ongthew-interiorof the closure skirt. Inthis type con struction,; when the closure is ,placed in sealing relationship'on the container, thelip of the container engages a sea-lingliner placedinthe interior of the closure anda seal is formedbetween the liner and the lip of the container. In order to insure a, propersea'l, it is. necessary to screw the closure tightly on the container, exerting pressure between .thethread of the closure and the thread ofthe container. This upward force. exerted on the thread ofthe cont-aiderby thecliosure creates a resultant forcenorrnaljto the upward forces, Since the container opening. ,is of .a diameter smallerthanthe diameter of the closure, this resultant force squeezes the neck -of. the container, distorting the same. The distortion of-z-rthe containerresulting from the squeezing acti'on causes-the closure to seektwo pressure points on which the closure exerts its maximum pressure. In regular glassware, the two pressure points are 180 degrees apart; and the area between the pressure points is exposed to stresses, which results in a weakening of the glass and in many instances the stress is so great that the container breaks.
This two-point contact between the closure and the container causes the closure to distort to the extent that the sealing properties of the closure are diminished.
This breakage is particularly prevalent in Wide mouth containers which have practically no shoulder between the body of the container and the neck portion carrying the thread. In containers of this type, the area under stress is on or close to the outer circumference of the container and is, therefore, exposed for contact when the containers are handled, as in packing in cartons or storing on shelves. This has caused considerable loss of containers and contents during handling.
One attempt to solve this problem is disclosed in Bromley Patent No. 2,585,624. This patent shows a plurality of relatively short depending projections on the thread of the container to serve as fulcrum points for the closure. The chief disadvantage of this arrangement is that the closure is unsupported in the areas Where the thread of the closure does not engage the projections. This unsupported condition permits the closure to flex upwardly in these areas and break the seal.
[in order to overcome the disadvantages resulting from the conventional type of container and closure described above, I have developed a thread finish for containers in which predetermined pressure areas are positioned on the thread of the container. For best results, it is essential that there be an odd number of pressure points a-r ranged around the neck of the container so positioned ice that no two, of fthemyor portions-thereof lie diametrically oppositeone another.
In a structure ofgthis, type, when the .closure is, applied tothe container and sealing pressure is, applied, the coma Patented Nov. .13, .1956
ponent of, (force normal, to the, sealing pressure will be.
distributedfamongran oddjnurnber of pressure points.
around "the circumference of the,.container, no .twotof which are diametrically oppositeoneanother; an'd,therefore, there is nodirect squeeze across themouth of the,
An object of this invention is to provide a continuous thread finish on containers Which..thread-,finishis provided withla predetermined number. ofpressure points spaced so as to greatly diminishlheanlount.ofstress set,
up by the application of a screw closure .to, the. mouth, of.
Other advantages will hecome obvious ,upon. examinaa tion of the attached drawings,,in-,which:
Figure 1 isaperspective view of a container havingthe proposed thread 'finish;
Figure 2 is a topplan yiew, of the same container-g and Figure 3 is a cross-sectionalview ofthe container with.
the closure applied in sealing relationship. Referring to Figure 1, ,there. is;.shown a. container 2 of'th'e wide mouth typehaving atop opening fi. Su=r rounding the ,neck of the, container is .a thread ,4 :which.
is .Of the desiredfshape, and -of,.suflicie nt. length .to overlap a short. distance in therarea .5..as shown in the draw ing. The thread 4 is, proyide'dwithareas. oinwhichthe.
thread has been substantially reducedin size. This leaves the outstanding areas 7 .uponrwhicjh the. pressure ofithe oneanothen, Th'eyare also of a sizeso that noipart of one projection will'be diametrically ,oppositeany ,portion of ano er p jec ion-1 W thianarrange ut t hi kind,
there ,are no,diametrically opposed.forces setuphwhenthe closure is screwed on the container. This eliminates to a great extent the stresses set up in the areas 6 between the pressure points. In the specific embodiment, there are three pressure points located around the circumference of the container. This is considered the minimum permissible; however, a larger number will. give the same result so long as no two or portions of any two are positioned diametrically opposite one another. It should be borne in mind that if a greater number than three is employed, the container closure will seek three points to apply the maximum pressure. In the specific embodiment shown comprising three projection-s 7, it has been found desirable to have each projection comprise approximately 50 degrees of the circumference of the container neck.
It will be noted that the container shown herein is substantially straight sided with a very slight shoulder 8 at the point where the neck of the container joins the body of the container. The invention disclosed herein is most useful in this type of container, inasmuch as there is a minimum amount of reinforcement provided by the shoulder. In another type of ware having a smaller neck opening and a larger shoulder, the shoulder increases the strength of the container; and there is less likelihood of breakage resulting from strain set up when the closure is placed in sealing position on the container.
The bottom surface of the thread of the container, which is the surface engaging the thread of the closure when the closure is placed on the container, is in a true uninterrupted helix and serves as a guide for the closure thread during the application of the closure to the container, thereby. eliminating the possibility of the thread of the closure jumping over the thread of the container.
This continuous surface of the thread holds the cap in proper sealing position, eliminating the likelihood of up ward flexing of the closure to break the seal.
Prom anobservation of Figure3, it will be seen that when the closure 9 is placed in sealing position on the container, the lower portion 10 of the threadl l of'the closure 9 is in continuous contact with the under surface 12 of the thread 4 on the neck of the container. It will also be observed that the outward projection 7 engages the full depth of the thread of the closure and the thread of the container diametrically opposite does not 'have the projection 7, and hence only the bottom portion of the thread of the closure is in contact with the bottom portion of the thread of the container.
I claim: Y
*1. A thread finish for a glass container, said finish comprising a continuous helical thread around the neck of the container for engagement with a complementary thread on a closure, said thread having an uninterrupted undersurface and being provided with a plurality of projections extending in a radially outwardly direction, said project-ions being so spaced that no two of them or por tions thereof are diametrically opposed across the mouth of the container.
2. A thread finish for a glass container, said finish comprising a continuous helical thread around the neck of the container for engagement with a complementary thread on a closure, said thread having an uninterrupted under-surface and being provided with an odd number of projections extending radiallyoutwardly therefrom, said projections being so spaced around the periphery of the container that no two of them are diametrically opposed across the mouth of the container.
3. A thread finish for a glass container, said finish comprising a continuous helical thread around the neck of the container for engagement with a complementary thread on a closure, said thread having an uninterrupted undersurface and being provided with three radially outwardly extending projections, said projections being so spaced that notwo of them are diametrically opposed across the mouth of the container. 7 1
4. 'A thread finish for a glass container, said finish com prising a continuous helical thread around the neck of 4 the container for engagement with a complementary thread on a closure, said thread having an uninterrupted undersu-rface and being provided with three radially outwardly extending projections, each projection comprising approximately degrees of the circumference of the neck of the container.
5. In a sealed glass container, the combination comprising a glass container having a continuous helical thread around the neck thereof, said thread having an uninterrupted under-surface and being provided with a plurality of radially outwardly extending projections located at dilferent points around the periphery of the container, and a closure applied in sealing position on said container, said closure having a thread complementary to the thread on the container, said closure thread being in continuous engagement with the undersurface of the container thread and in engagement with the outwardly extending projections of the container thread at several points around the periphery of the container, no two of which points are diametrically opposed to one another. 7 V
6. A thread finish for a glass container, said finish comprising a continuous helical thread around the neck of the glass container for engagement with a complementary thread on a closure, said thread having an uninterrupted undersurface and having a portion of said thread removed around the outer periphery thereof to form radially outstanding projections on the remaining portion of the thread, the arrangement of said projections being such that no two projections or portions thereof are diametrically opposed across the mouth of the container.
' References Cited in the file of this patent UNITED STATES PATENTS Brom-ley Feb. 12,