US3599821A

US3599821A - Closure device of plastic for tubes and containers

Info

Publication number: US3599821A
Application number: US12085A
Authority: US
Inventors: Geinrich Eggert; Hans Schwartz
Original assignee: Individual
Current assignee: Individual
Priority date: 1969-02-21
Filing date: 1970-02-17
Publication date: 1971-08-17
Anticipated expiration: 1988-08-17
Also published as: DE1908821A1; GB1298769A; FR2033370B1; FR2033370A1; CH505008A

Abstract

A closure device of plastic which comprises a cap which is to be fitted over and pressed upon the open end of a container and carries on the inside of its top a resilient hollow plug which is inserted into the open end of the container and has one or more locking projections which snap into an inner annular groove in the container wall or over an annular projection on this wall when the cap seals the container tightly. For unlocking the plug from the container wall to permit the cap to be withdrawn, a central part of the top is depressed, whereby a central stem at the inside of the plug effects a deformation of the plug so that the locking projection of projections of the plug are retracted from the annular groove or projection of the container wall.

Description

United States Patent CLOSURE DEVICE OF PLASTIC FOR TUBES AND CONTAINERS 7 Claims, 8 Drawing Figs.

Int. Cl .Qf. 865d 39/12 Field of Search 215/52- Primary Examiner-George T. Hall Anorney- Flynn and F rishauf ABSTRACT: A closure device of plastic which comprises a cap which is to be fitted over and pressed upon the open end of a container and carries on the inside of its top a resilient hollow plug which is inserted into the open end of the container and has one or more locking projections which snap into an inner annular groove in the container wall or over an annular projection on this wall when the cap seals the com tainer tightly. For unlocking the plug from the container wall to permit the cap to be withdrawn, a central part of the top is depressed, whereby a central stem at the inside of the plug effects a deformation of the plug so that the locking projection of projections of the plug are retracted from the annular groove or projection of the container wall.

PATENTEUAusmsn 3,599,821

SHEET 1 0F 3 Fig. la

Fig. 1b

Fig. lc

PATENTEDmcmsn 3,599,821

SHEET 2 OF 3 Fig. 2a

PATENTEDAUGHIBTI 3,599,821

SHEET 3 BF 3 Fig.3a

Fig.3b

Fig. dc

CLOSURE DEVICE F PLASTIC FOR TUBES AND CONTAINERS The present invention relates to a closure device for tubes, cans, bottles or other containers, and more particularly to such a device which may be used repeatedly for tightly closing and opening the mouth of the respective container or of any other container which has a mouth of the same size.

Among the multitude of such closure devices as were disclosed prior to this invention there are some which are of such a complicated construction that their manufacture renders them too expensive, while others are so difficult to manipulate as to be impractical. Those closure devices, however, which are of a more simple type are usually not sufficiently secure, especially for rescaling a container after it has once been opened. All of the known closure devices of the above-mentioned type have the further disadvantage that they may be opened only by applying considerable force or by means of rather complicated manipulations.

It is an object of the present invention to provide a closure device of the type as first mentioned above which is made of plastic and may be manufactured at a relatively low cost and be manipulated very easily for opening and tightly closing a bottle, can, tube or other container and may also be used repeatedly with the same effect on the same container or in different containers with mouths of the same size.

The closure device according to the invention comprises a cap which is adapted to be fitted over the open end oftlie container and has a side wall for surrounding the upper endportion of the container and a top or cover for closing theopen end. This cover may be either resilient and directly secured to or integral with the side wall of the cap or it may form an element separate from the cap which is inserted into a central aperture in a top wall of the cap and is guided therein so as to be movable in the axial direction of the cap. The closure device further comprises a resilient hollow plug. which has a substantially double-conical shape, that is, substantially the shape of two hollow cones which are joinedto each other at their common base. This plug has one end eormected or secured to the inner side of the top wall ofthe cap and-due-to its own resilience and its particular shape it has the tendency to expand uniformly in all radial directions at its widest port, that is, at the mentioned base of the two cones. At this part, the plug is provided with a small annular outwardly projecting rim. When the cap is fitted over the open end of a container, this plug will at the same time engage into the open end, and when the cap is pressed downwardly so far that a resilient sealing surface either on the top wall of the cap or on the part of the plug which is secured to the cap is compressed and tightly closes the open end of the container, the projecting rim snaps downwardly over a small annular projection on the inner wall of the container or into an annular recess in this wall and thereby locks the cap securely in its sealing. position on the container.

For unlocking and removing the cap. the resilient cover of the latter or the separate cover element is connected to thelower end of the hollow plug by means of a central stern. lfthe resilient cover or the cover element is depressed from above, the stern will transmit this movement to the lowercnd ofthe hollow plug. The plug will thereby be extended toward the inside of the container and the locking; rim of the plugwill thereby be radially contracted and pulled out of its engagement with the annular recess in the wall of the container or with the annular projection on this wall, whereupon the cap may be pulled off the upper end of the container. If this stem is firmly secured at its opposite ends to the cover or cover'element and to the lower end of the hollow plug. it will serve as a means for preventing the cap from being pulled off 'the container by force. If such an attempt is made; whilethe cover or cover element is not also depressed, even the slightest traction upon the cover will be transmitted by the stem to the lower even more firmly into the locking recess or against the locking projection of the container wall.

According to another embodiment of the invention, the hollow plug which may have a general shape like the plug as previously described is divided into a plurality of segments which are secured to or integral with each other at their upper ends but are separate from each other down to their lower ends. At the maximum diameter of this plug, the segments are provided with equal outer locking projections which together correspond to the locking rim of the plugs as previously described. The central stem is secured at its upper end to the cover or cover element of the cap and its lower end projects through the separate lower ends of the segments which abut A against its peripheral surface without being secured thereto. A

short distance above the point of engagement of the lower ends of the segments with the stem, the latter is provided with an annular recess. When the cover or cover element is depressed for a certain distance, the lower end of the stem passes through the lower ends of the segments until the latter snap into the annular recess in the stem and thereby contract the locking projections which are thus withdrawn from the locking-recess in the wall of the container or from the locking projection on this wall so that the cap may then be withdrawn from the end of the container. Apart from the fact that the plug according to this embodiment of the invention might be more easily produced than the one-piece plug as previously described, it also has the advantage that an accidental pressure upon the cover or cover element of the cap will not immediately cause the locking rim of the plug to be contracted and withdrawn from the annular recess or the annular projection of the container wall, but that a greater pressure upon the cover or cover element will be required so as to shift the stem until the lower ends will engage into the annular recess of the stem.

From the previous description it is evident that a mere pull upon the cap will not remove it from the container unless a certain downward pressure is exerted at the same time upon the cover or cover element of the cap. Turning the cap in one direction or the other about its axis will not effect or facilitate its removal. The closure device according to the invention has the additional advantage that an increase of the internal pressure of the material in the container acts upon the lower side of the plug and increases the locking action of the plug upon the wall of the container.

The entire closure device according to the invention may be made of a relatively stiff plastic which, however, is sufficiently resilient for attaining a good sealin'g effect and to permit the same device to be used many times.

The features and advantages of the present invention will become further apparent from the following description chereofwhich is to be read with reference to the accompanying drawings, in which:

FIG. to shows a central longitudinal section of the new closure deviceaccording to one embodiment of the invention;

FIG. 1b shows the device according to FIG. la partly in section and partly in a side view;

FIG. It: shows a longitudinal section of a part of a closure device similar to that as shown in FIGS. la and 1b, but in loclting engagement with a container with an annular inner projection;

FIG. 25: shows a longitudinal section ofa' closure device accordingto a modification of the invention;

FIG. Zhshows a longitudinal section of a closure device according'to anothermodification of the invention;

FIG. 3a'sli'ows a longitudinal section of a closure device accordingto a further modification of the invention;

HG. shows partly in section and partly in a side view substantially the same closure device as shown in FIG. 30, but in lookingengagement'with a container with an annular inner projection; while FIG. 3:- shows a longitudinal section of a part of the same part of the plug and will cause the locking 'rim to be pressed closuredevice asshown in FIG. 3b.

The closure device as shown in FIGS. 10, lb and 1c of the drawings comprises a cap 1 of plastic the cover part of which is resilient and integral with its sidewall. A hollow resilient plug 4 which is likewise made of plastic has a substantially double-conical shape which has on its upper end an outwardly projecting part 7 which is firmly connected to the cap 1 2 and is provided with an annular downward projection 6 which is adapted to engage with the inner side of the open mouth of the container 8 and to serve as a sealing gasket for closing the mouth. The upper and lower. cones of plug 4 have the tendency to move toward each other and thereby to enlarge the diameter of their common base. At this base, plug 4 is provided with a small annular outwardly projecting rim 5 which, when the cap is fitted over and pressed down upon the mouth of the container 8 and the plug 4 is at the same time inserted into the mouth, snaps either into an annular recess 9 in the wall of the container, as shown in FIGS. la and lb, or over an annular projection 9 on this wall, as shown in FIG. 1c, and thereby locks the cap in its sealed position.

In order to permit the plug 4 to be unlocked from the container wall when the

cap

1, 2 together with the plug is to be withdrawn from the container 8, a central stem 3 is provided at the inside of the plug and either connected or secured at its enlarged opposite ends to the cover part 2 and the lower end of plug 4. When the resilient cover part 2 is depressed, the lower end of the stem 3 presses the lower part of plug 4 downwardly and thereby elongates the plug which causes its projecting rim 5 to be contracted and thereby pulled out of the annular recess 9 in the container wall, as shown in FIGS. la and lb, or out of engagement with the annular projection 9' on this wall, as shown in FIG. 10. If the

cap

1, 2 is at the same time pulled upwardly, the entire closure device may be easily removed from the container.

The closure device as illustrated in FIG. 2a differs from the device according to FIGS. la, b and c primarily by the provision of a separate cover element 2' to which the upper end of the central stem 3 is connected and which is inserted into an aperture 10 in the top wall of cap 1 and guided by the wall of this aperture. Annular shoulders on this wall prevent the cover element 2 from being pushed upwardly or downwardly out of the aperture 10. This closure device differs further from that as shown in FIGS. 1a, b and c by the fact that the plug 4 does not form an element separate from the cap 1 but that it is integral with the cap. The annular sealing projection 6 is therefore likewise integral with cap 1. The lower end of stem 3 is rigidly secured to the center of the lower end of plug 4, and along the line of its greatest diameter the plug is again provided with an annular outwardly projecting rim 5 which is adapted to engage into an annular recess 9 in the container wall 8. The operation and the effect of the closure devices as shown in FIGS. la, b and c and in FIG. 2a, respectively, are practically the same. However, while the cover part 2 of cap I of the first closure device which is integral with the cap must be resilient, the separate cover element 2' of the cap of the second closure device may be rigid since it is guided in the axial direction by the wall of the aperture 10.

The closure device as shown in FIG. 2b differs from the device according to FIG. 2a merely by the shape of plug 4 and by the manner of connecting the lower end of the stem 3 to the lower end of the plug.

H68. 30, b and 0 illustrate a further embodiment of the invention in which the hollow plug consists of a plurality of segments 4' which are integral at their upper ends with an outwardly projecting sealing part 7 similar to that as shown in FIGS. la, b and c, while their lower inner ends 11 are not secured to each other. Segments 4 are molded so as to have the tendency to bend radially toward the central axis of the cap. At the maximum diameter of the plug, all of the segments 4' are provided with locking projections 5' which are disposed at the same level. The upper end of the central stem 3' is rigidly secured to the resilient cover part 2 which is integral with the side wall of cap I, and the lower cylindrical end portion 12 of the stem projects downwardly between and beyond the separate lower inner ends 11 of the segments 4' which, due to their tendency to bend toward the central axis of the cap, abut against the endportion 1'2. 'Due to this pressure of the end portion 12 against the ends 11 of the segments, the maximum diameter of the plug. that is, the diameter of the locking projections 5', is increased so that, when the cap I, 2 is applied over the open end of the container 8; and the plug segments 4' are at the same time inserted into the mouth of the container, the segments will at first be compressed until the cap is pressed down so far that the mouth of the container will be tightly sealed by the gasket or sealing part of the plug, at which time the locking projections 5' of the segments will snap into the annular recess 9 or over the annular, preferably rounded projection 9" of the container wall 8 and thus lock the cap I, 2 in its sealing position.

For unlocking the plug so as to permit the cap I, 2 to be withdrawn from the mouth of the container, the central stem 3' is provided above the end portion 12 with an annular recess 13 of a depth substantially equal to the depth of the annular recess 9 or the horizontal thickness of the annular projection 9" of the container wall 8. When the resilient cover part 2 is depressed for a sufficient distance, the lower inner ends 11 of the plug segments 4' will snap into this recess 13 and the locking projections 5' will thereby be withdrawn from the recess 9 or the projection 9" of the container wall so that the entire closure device may then be easily withdrawn from the container.

While the entire closure device consists of relatively tough plastic and is preferably produced by injection molding, its plug part 4 or 4' is molded so as to exert a relatively strong spring action. The closure device may then be employed for a very long time for opening and tightly closing a container with a mouth of an appropriate size or different containers all of which have a mouth of such a size.

Although our invention has been illustrated and described with reference to the preferred embodiments thereof, we wish to have it understood that is in no way limited to the details of such embodiments but is capable of numerous modifications within the scope of the appended claims.

Having thus fully disclosed our invention, what WE claim is:

l. A closure device of plastic for tubes, cans, bottles or other container each having a locking part formed by an annular recess in or an annular projection on the inner wall of the container wall near the open mouth of the container, said device comprising a cap having a top wall, the central part of said wall being adapted to be resiliently depressed, gasket means for tightly sealing said mouth when said cap is pressed thereon, a hollow resilient plug of a substantially double-conical shape having one end connected to said top wall and having an annular outwardly projecting locking rim at the level of the maximum diameter of said plug, said rim being adapted to snap into locking engagement with said locking part of said container wall when said plug is inserted into said mouth and said plug is pressed down so as to be in tight sealing engagement with said mouth, and a central stem connected to said top wall and adapted when said top wall is depressed to act upon the lower part of said plug so as to deform said plug in such a manner that said projecting rim is contracted and withdrawn from said locking part of said container wall so that said entire device may then be withdrawn from said container.

2. A closure device as defined in claim I, in which the upper end of said central stem is firmly secured to said top wall of said cap.

3. A closure device as defined in claim I, in which the upper end of said central stem is firmly secured to said top wall of said cap and its lower end to the lowest part oi said plug.

4. A closure device as defined inclaim 1, in which said top wall of said cap has a central aperture, and a separate cover disk inserted into said aperture and guided by the wall thereof for a limited upward and downward movement in the axial direction of said cap, the upper end of said stem being connected to said cover disk.

5. A closure device as defined in claim I, in which said gasket means are formed by the upper end portion of said plug which is connected to said top wall of said cap.

6. A closure device as defined in claim 4, in which said gasket means are formed by the upper end portion of said plug which is integral with the part of said top wall surrounding said cover disk.

7. A closure device as defined in claim I, in which the part of said plug which is to be inserted into said container is divided into a plurality of segments each having a projecting edge at the same level so that said edges together form said locking rim, said segments extending downwardly from said edges and toward the central axis of said cap and tending to bend resiliently toward said axis so as to retract said edges from said locking part of said container wall, said stem being rigidly secured at its upper end to said top wall and adapted to be depressed thereby, said stem having a lower end portion extending between and in abutting engagement with the loose lower ends of said segments so as normally to maintain said locking rim at its maximum locking diameter, said stem having an annular recess above said lower end portion having a depth substantially equal to the depth of said locking part so that, when said top wall is sufficiently depressed. said lower ends of said segments slide along said lower end portion of said stem, then engage into said recess and move resiliently toward each other, whereby the diameter of said locking rim decreases and said rim disengages from said locking part of said container wall so that said entire device may then be withdrawn from said container.

Claims

1. A closure device of plastic for tubes, cans, bottles or other container each having a locking part formed by an annular recess in or an annular projection on the inner wall of the container wall near the open mouth of the container, said device comprising a cap having a top wall, the central part of said wall being adapted to be resiliently depressed, gasket means for tightly sealing said mouth when said cap is pressed thereon, a hollow resilient plug of a substantially double-conical shape having one end connected to said top wall and having an annular outwardly projecting locking rim at the level of the maximum diameter of said plug, said rim being adapted to snap into locking engagement with said locking part of said container wall when said plug is inserted into said mouth and said plug is pressed down so as to be in tight sealing engagement with said mouth, and a central stem connected to said top wall and adapted when said top wall is depressed to act upon the lower part of said plug so as to deform said plug in such a manner that said projecting rim is contracted and withdrawn from said locking part of said container wall so that said entire device may then be withdrawn from said container.

2. A closure device as defined in claim 1, in which the upper end of said central stem is firmly secured to said top wall of said cap.

3. A closure device as defined in claim 1, in which the upper end of said central stem is firmly secured to said top wall of said cap and its lower end to the lowest part of said plug.

4. A closure device as defined in claim 1, in which said top wall of said cap has a central aperture, and a separate cover disk inserted into said aperture and guided by the wall thereof for a limited upward and downward movement in the axial direction of said cap, the upper end of said stem being connected to said cover disk.

5. A closure device as defined in claim 1, in which said gasket means are formed by the upper end portion of said plug which is connected to said top wall of said cap.

7. A closure device as defined in claim 1, in which the part of said plug which is to be inserted into said container is divided into a plurality of segments each having a projecting edge at the same level so that said edges together form said locking rim, said segments extending downwardly from said edges and toward the central axis of said cap and tending to bend resiliently toward said axis so as to retract said edges from said locking part of said container wall, said stem being rigidly secured at its upper end to said top wall and adapted to be depressed thereby, said stem having a lower end portion extending between and in abutting engagement with the loose lower ends of said segments so as normally to maintain said locking rim at its maximum locking diameter, said stem having an annular recess above said lower end portion having a depth substantially equal to the depth of said locking part so that, when said top wall is sufficiently depressed, said lower ends of said segments slide along said lower end portion of said stem, then engage into said recess and move resiliently toward each other, whereby the diameter of said locking rim decreases and said rim disengages from said locking part of said container wall so that said entiRe device may then be withdrawn from said container.