Cap Structure Holding An Inner Closure

Abstract

A cap structure holding an inner closure within an outer cap as one body, which is conveniently fixed to a container neck by means of a capping machine and leaves the inner closure on a container neck when the outer cap is removed from a container neck after the cap has been fixed on a container neck.

Description

FIELD OF THE INVENTION

This invention relates to a cap structure holding an inner closure and more particularly to a cap structure holding an inner closure suitable for containers for liquids, semiliquids, granular materials, and the like.

BACKGROUND OF THE INVENTION

It is well known that an inner closure is used with the purpose of controlling the quantity of contents being dispensed, regulating the direction of distribution of contents being dispensed, or restricting the cross section of flow of contents being dispensed to such specific contour as a circle, star, etc., when liquids, semiliquids, granular materials, and the like are dispensed from containers. Examples of such an inner closure are one for a liquid detergent container which controls the quantity of detergent being dispensed by means of small perforations thereon, one for a chemical seasoning container having a large number of small perforations thereon, and one for a cream or mayonnaise container having a hole through which contents are squeezed. In such applications it is required that a cap and an inner closure can be efficiently fixed as one body on a container neck by means of a capping machine and that when the user removes the cap from a container neck the cap is removed but the inner closure remains on a container neck. A conventional typical cap structure which leaves an inner closure on a container neck when the cap is removed from a container neck is shown in FIG. 1. This cap structure forms a cap 3 having a top plate 1 and a skirt section 2, on the internal periphery of the skirt section 2 being provided a bead 4, and also forms an inner closure 7 having a top plate 5 and a skirt section 6, the free end edge of the skirt section 6 being projected inwards to form a bead 8, and prevents the inner closure 7 from getting out of place by holding the external peripheral end 9 of the skirt section 6 of the inner closure 7 with the bead 4 on the said cap and also by engaging the bead 8 on the inner closure 7 with a groove 11 formed along the external periphery of the bottle neck 10 after the cap has been fixed on the bottle neck 10.

Although expressed in words as above, this cap structure has its technical drawbacks in that the bead 4 to be formed on the internal periphery of the cap 3 and the bead 8 to be formed on the inner closure 7 can not be made so high in actuality due to difficulties in demolding -- 0.5 mm at best, and because of lack of uniformity in molding dimensions -- variation as much as 0.2 to 0.3 mm is common, the force to retain the inner closure is not so great and therefore retention of the inner closure by the cap and fixation of the inner closure to the container neck are not secure after the cap has been fixed to a container.

SUMMARY OF THE INVENTION

The present invention provides a cap structure which retains the inner closure most effectively, completed as the result of study with the purpose of solving drawbacks involved in the conventional cap structure as described above.

The primary object of the present invention is to provide a cap structure in which an inner closure is securely held in a cap before the cap is fixed on a container neck and the inner closure is securely retained on a container retained after the cap has been fixed on a container neck.

The secondary object of the invention is to provide a cap structure in which retention of an inner closure in a cap is secure before the cap is fixed on a container neck and retention of an inner closure on a container neck is secure and stable after the cap has been fixed on a container neck and an inner closure has the retaining mechanism suitable for plastics-molded containers which are difficult to control to accurate dimensions.

The third object of the invention is to provide a cap structure in which an inner closure 7 is securely held by a cap 3 while the cap is being fixed by a capping machine and an inner closure is held in such a manner that facilitates handling.

The fourth object of the invention is to provide a cap structure in which is held an inner closure in such a way that an inner closure is smoothly engaged with a groove formed on the external periphery of a container neck when a cap and an inner closure are fixed as one body on a container neck.

The fifth object of the invention is to provide a cap structure in which is held an inner closure so designed that the cap alone is easily removed when the cap is unscrewed from a container neck, yet the inner closure remains securely on a container neck.

The sixth object of the invention is to provide a cap structure in which retention of an inner closure in a cap and retention of an inner closure on a container neck is made secure in spite of lack of uniformity in molding dimensions, by simply forming a moldable low bead or groove on a cap, inner closure, or container neck, which does not need a precise mold nor skilled technique so much.

The invention provides, in combination, a container, an inner closure, and a cap, the container comprising a tubular neck having a portion of larger outer diameter disposed suprajacent a portion of smaller outer diameter to provide a downwardly facing shoulder means between the portions, the inner closure comprising a top plate having means defining a dispensing opening therethrough, and a peripheral skirt, circumferential resilient flange means extending generally horizontally radially inwardly and radially outwardly from connection with the skirt, near the lower extent thereof, the circumferential flange means being flexible generally angularly about the angular axis of the skirt at the level of the flange means connection therewith to general frusto-conicality, oriented to have its inner peripheral diameter disposed above where it had been when the flange means was generally horizontal and to have its outer peripheral diameter disposed below where it had been when the flange means was generally horizontal, the cap comprising a top plate and a peripheral skirt having an inner peripheral surface, the skirt having bead means formed at a level about the surface, the diameter of the outer periphery of the flange means when unflexed being at least as large as the innermost radial extent of the bead means on the cap, relative to the longitudinal axis of the inner closure so that in inserting the inner closure into the cap so the two skirts project in the same sense from the two respective top plates and urging the top plate of the inner closure sufficiently toward the top plate of the cap that the outer periphery of the flange means passes the bead means on the cap to temporarily assemble the inner closure to the cap, the flange means are engaged by the bead means as these two pass, the diameter of the inner periphery of the flange means after the flange means outer periphery has passed the bead means on the cap being smaller than the radially outer extent of the larger outer diameter portion of the tubular neck of the container so that as the temporarily assembled inner closure and cap are installed upon the tubular neck the inner periphery of the flange means engages as it passes the larger outer diameter portion of the tubular neck and flexes the flange means toward the general frusto-conicality, this disposition being maintained when the inner periphery of the flange means becomes disposed below the downwardly facing shoulder means at least to such extent that the outer periphery of the flange means is of smaller diameter than the innermost radial extent of the bead means on the cap, relative to the longitudinal axis of the inner closure, so that the temporary assembly of the inner closure to the cap is extinguished.

Other objects and advantages of the invention will be apparent from the following description taken in conjugation with the accompanying drawing wherein:

FIG. 1 is an overall front view of an example of a conventional well-known cap structure holding an inner closure, fixed on a container neck, major parts of the structure being shown as a sectional view;

FIG. 2 is a longitudinal sectional side view of an inner closure of a first embodiment of the invention, cut in the direction of diameter;

FIG. 3 is a longitudinal sectional side view of an inner closure, as shown in FIG. 2, held by a cap;

FIG. 4 is an overall front view of a cap structure of the first embodiment of the invention fixed on a container neck, major parts of the structure being shown as a sectional view;

FIG. 5 is a front view same as FIG. 4 above, showing a cap structure of a second embodiment of the invention fixed on a container neck, major parts of the structure being shown as a sectional view;

FIG. 6 is a sectional view of a catch of a cap.

DETAILED DESCRIPTION OF THE INVENTION

With reference now to FIG. 2 and FIG. 4, the cap structure of the first embodiment of the invention is explained.

In FIG. 2 the numeral 20 designates an inner closure, integrally molded from plastics material into a hollow cylindrical shape having a top plate 21 and a skirt 22. At the center of the said top plate 21 is provided a dispensing hole 23, through which such contents as liquids, semiliquids, granular materials, and the like are dispensed. On the free end of the skirt 22 of the said inner closure 20 is formed a flange 24 horizontally with respect to the skirt 22. The external peripheral end of this flange 24 is designated by the numeral 25, and the diameter at this part is assumed a. And the internal peripheral end of the flange 24 is designated by the numeral 26. Hence, the external peripheral end 25 and internal peripheral end 26 of the flange 24 project inwards and outwards of the inner closure 20 a little beyond the internal and external peripheral surfaces of the skirt 22, and yet the flange 24 rotates with respect to the skirt 22 as shown by an alternate long and short dash line in FIG. 2.

In FIG. 3 the numeral 27 designates a cap, integrally molded from plastics material into a hollow cylindrical shape having a top plate 28 and a skirt 29. At the intermediate position of the said skirt 29 is formed a bead 30 along the internal peripheral surface thereof. The inside diameter b at the internal surface above the said bead 30 is not greater than a; in other words b .ltoreq. a. Consequently, when the inner closure 20 is placed in the cap 27, the flange 24 of the inner closure 20 rotates inwards of the inner closure 20 around the connecting part to the skirt 22, and thus the external peripheral end 25 of the flange 24 fits to the bead 30 of the cap 27, causing the inner closure 20 to be securely held. (Refer to FIG. 3.) The diameter of the internal peripheral end 26 of the inner closure 20 when held in the cap is assumed c. In case the inner closure 20 is made of a resilient material such as plastics as with the examples of the invention, the flange 24 of the inner closure 20 tends to return to the horizontal state orthogonal with respect to the skirt 22 in the vertical state as shown in FIG. 2, resulting in more secure fit.

Now, as described in the above, on the container neck 31 to be affixed with the cap 27 holding the inner closure 20 therein, is formed a groove 32 at the external peripheral section mating with the internal peripheral end 26 of the flange 24 of the said inner closure 20, as shown in FIG. 4. Assuming the outside diameter of this groove 32 to be d, the relation d > c is established between d and the diameter c of the internal peripheral end 26 of the flange 24 when the said inner closure 20 is held securely by the cap 27. The greater diameter part above the said groove 32 is designated by the numeral 33. Therefore, when the cap 27 holding the inner closure 20 is fixed on the container neck 31, the flange 24 of the inner closure 20 is rotated more than the state as shown in FIG. 2, because the relation d > c is established when the internal peripheral end 26 of the flange 24 fits the groove 32. (Refer to FIG. 4.) At this time the outside diameter of the external peripheral end 25 of the flange 24 decreases a little, becoming smaller than b; to be exact, it gets smaller than the inside diameter of the bead 30. Thus, the engagement of the cap 27 and the inner closure 20 is easily released, enabling one to remove the cap 27 while leaving the inner closure 20 on the container neck 31. At this time the flange 24 of the inner closure 20 is hooked by the greater diameter part 33 of the container neck 31, with complete prevention of disengagement.

In the example described in the above, the flange 24 of the inner closure 20 is molded on the entire periphery of the lower end of the skirt 22, but the flange may be of discontinuous type molded at a plurality of positions (at least two positions equally dividing the circumference) on the circumference.

Referring now to FIG. 5 and FIG. 6, a cap structure in the second example of the invention is described.

The numeral 31 designates the container neck, on the upper part of the external periphery of which is formed a groove 32. An upward tapered section 34 is formed from the upper part of the groove 32 to the upper end of the container neck 31, in order to facilitate the inner closure 20 to be fixed. The inner closure 20 is nearly of hollow cylindrical shape having a top plate 21 and a skirt 22, as with the first example described in the above. To the top plate 21 is provided a dispensing nozzle 23. Also, at the lower end of the said skirt 22 is formed as one body a flange 24 which inclines toward the inside of the inner closure 20. Therefore, the inside diameter of the internal peripheral end 26 of the flange 24 is made sufficiently smaller than the outside diameter of the greater diameter part 33 above the groove 32, so that the secure engagement is accomplished. In the thickness 35 of the flange 24 is formed a slit 36 along the entire periphery thereof. This slit 36 is to facilitate the external peripheral end 25 of the flange 24 to bend inwards.

The cap 27 is nearly of hollow cylindrical shape with a top plate 28 and a skirt 29, which engages with the container neck 31. On the internal periphery of the cap is formed a plurality of beads 30 at the at the positions corresponding with the external peripheral end 25 of the flange 24 of the said inner closure 20. (Six positions in the illustrated example.) The outside diameter of the external peripheral end of the flange of the inner closure 20 is made considerably larger than the inside diameter of the beads 30 of the cap 27 so that the inner closure 20 is securely held inside the cap 27. Therefore, when the cap is placed on a capping machine the inner closure 20 is securely held in the cap 27, and once the cap and inner closure are fixed as one body on a container neck 31 the internal peripheral end 26 of the flange 24 of the inner closure 20 mates with the groove 32 and disengagement in the upward direction is securely prevented by the greater diameter part 33. When the cap 27 is to be removed the cap can be removed with ease leaving the inner closure securely held on a container neck because the external peripheral end 25 of the flange 24 is easily bent inwards owing to the slit 36.

As described in the above, the present invention facilitates the handling of the cap because the inner closure is securely held in the cap when the cap is placed on a capping machine. Further, when the cap is removed from a container neck after the cap has been fixed on a container neck, it is possible to leave the inner closure alone on a container neck because the internal peripheral end of the flange of the inner closure is so designed as to engage securely with the groove formed on the external periphery of the container neck. Therefore, this structure can be said to be convenient for plastics-molded containers which are difficult to control their dimensions accurately.

It will be understood that the invention is not to be limited to the exact structure described in the examples, but that various changes and modifications may be made in the detailed structure of the examples without departing from the scope of the invention, as defined in the appended claims.

Claims

We claim:

1. In combination:

a container, an inner closure, and a cap;

said container comprising a tubular neck having a portion of larger outer diameter disposed suprajacent a portion of smaller outer diameter to provide a downwardly facing shoulder means between said portions;

said inner closure comprising a top plate having means defining a dispensing opening therethrough, and a peripheral skirt;

circumferential resilient flange means extending generally horizontally radially inwardly and radially outwardly from connection with said skirt, near the lower extent thereof, said circumferential flange means being flexible generally angularly about the angular axis of the skirt at the level of the flange means connection therewith to general frusto-conicality oriented to have its inner peripheral diameter disposed above where it had been when the flange means was generally horizontal and to have its outer peripheral diameter disposed below where it had been when the flange means was generally horizontal;

said cap comprising a top plate and a peripheral skirt having an inner peripheral surface; said skirt having bead means formed at a level about said surface;

the diameter of the outer periphery of the flange means when unflexed being at least as large as the innermost radial extent of the bead means on said cap, relative to the longitudinal axis of the inner closure, so that in inserting the inner closure into the cap so the two skirts project in the same sense from the two respective top plates and urging the top plate of the inner closure sufficiently toward the top plate of the cap that the outer periphery of the flange means passes the bead means on the cap to temporarily assemble the inner closure to the cap, the flange means are engaged by the bead means as these two pass;

the diameter of the inner periphery of the flange means after the flange means outer periphery has passed the bead means on the cap being smaller than the radially outer extent of said larger outer diameter portion of the tubular neck of the container so that as the temporarily assembled inner closure and cap are installed upon said tubular neck the inner periphery of the flange means engages as it passes the larger outer diameter portion of the tubular neck and flexes the flange means toward said general frusto-conicality, this disposition being maintained when the inner periphery of the flange means becomes disposed below said downwardly facing shoulder means at least to such extent that the outer periphery of the flange means is of smaller diameter than the innermost radial extent of the bead means on said cap, relative to the longitudinal axis of the inner closure, so that the temporary assembly of the inner closure to the cap is extinguished.

2. The combination recited in claim 1 wherein the diameter of the outer periphery of the flange means when unflexed is larger than the innermost radial extent of the bead means on said cap, relative to the longitudinal axis of the inner closure so the flange means must flex toward said general conicality to pass said bead means when being temporarily assembled to said cap.

3. The combination recited in claim 2 further including means defining a circumferential groove in the outer periphery of the flange means for increasing the flexibility of the flange means adjacent this groove.

4. The combination recited in claim 2 wherein the bead means is constituted by angularly intermittently placed discrete protuberances.

5. The combination recited in claim 2 wherein the container tubular neck flares outwardly as its larger outer diameter portion proceeds down toward said downwardly facing shoulder means to cam the flange means toward said frusto-conicality during said installation of the temporarily assembled inner closure and cap upon the tubular neck of the container.