GB2227239A

GB2227239A - Container cap

Info

Publication number: GB2227239A
Application number: GB8901258A
Authority: GB
Inventors: Tom Lai
Original assignee: Individual
Current assignee: Individual
Priority date: 1989-01-20
Filing date: 1989-01-20
Publication date: 1990-07-25
Also published as: GB8901258D0

Abstract

A tamperproof container cap 1 comprises a screw-threaded wall 11, annular sealing rings 112 within the base, a tamperproof snap ring 13 provided with a plurality of snap hooks 131, and a connecting ring 12 connected to the wall 11 and ring 13 by tearable rings 115 so that pulling tears off the connecting ring. As shown, when the cap is twisted on a container mouth in a clockwise direction, the screw thread on the wall 11 moves downwardly along a container neck screw thread to generate a vertical pressure to spread the snap ring on a rib (23 Figs 4, 8) on the container neck. The cap continues to move smoothly down to the lower side of the container neck rib (23) to close the container mouth to render the container tamperproof. <IMAGE>

Description

Title: Container Cap The present invention relates to a twistable, self-sealing and tamperproof container cap and also a container including such a cap.

Recently, food and beverages have been poisoned by gangsters and this has led to both consumers and manufacturers becoming concerned about the safety of tamperproof packaging. In order to render a container tamperproof, when using an ordinary plastic screw thread cap, adhering a sealing label to the container mouth or wrapping the container cap and neck or even the container body with the shrinkable film results in a poor wrapping.

Moreover, packing materials are wasted, more working hours to manufacture are needed and the costs are higher for larger-sized containers.

Alternatively, a polyethylene plastic cap may be provided and pressed to the container so that the cap body and a snap ring on the lower edge thereof can mutually catch the snap hook respectively; if the middle connecting band is not torn off, the cap cannot be opened. Such a method has been a drawback for the container with a wide mouth since the cap cannot be pressed to cover the container, and instead thereof, the container has to be placed in a stand, then the cap forced to cover and engage the container mouth which is rather inconvenient. Furthermore, when opening the cap, the contents therein tend to pour out because of pressing force only on one side thereof.

According to the present invention there is provided a twistable, self-sealing and tamperproof container cap on an annular inner wall of which is provided a plurality of mutually indented threads for engagement with corresponding screw threads on the neck of a container to which the cap is to be fitted, a plurality of annular sealing rings being provided within the base of the cap, a tamperproof snap ring being disposed at the lower edge of the cap the inner side of which is provided with a plurality of cap snap hooks, and a connecting ring, disposed in a middle portion of the cap, tearable rings being connected to the cap body and the tamperproof snap ring, whereby pulling a tab tears off the connecting ring so as to separate the cap body from the tamperproof snap ring.

The invention will now be described further by way of example with reference to the accompanying drawings in which: Fig. 1 is an elevational view of a twistable, self-sealing and tamperproof container cap according to the present invention, Fig. 2 is an underside view of the cap shown in Fig. 1, Fig. 3 is a vertical sectional view through the cap shown in Figs. 1 and 2., Fig. 4 is an elevational view of an example of an injection moulded container for use with the cap shown in Figs. 1 to 3, Fig. 5 is a sectional elevation view of the container and cap prior to closure by twisting the cap, Fig. 6 is a view similar to that of Fig. 5 after closure by twisting the cap, Fig. 7 is an elevation, partly in section, of the position after tearing off the connecting band, and Fig. 8 is a sectional elevation of the container and cap, the container being blow moulded.

The twistable, self-sealing and tamperproof container cap of the present invention can be described as follows in conjunction with the accompanying drawings: As shown in Fig. 1, 2 and 3, the cap 1 of the present invention consists of three portions: a cap body 11, disposed at the upper end, is a main body for closing or opening the container, and an annular inner wall is provided with four-start (or a plurality of starts) screw thread 111 with equal size, height and interval which are mutually indented in keeping with the container neck screw thread 22 (as shown in Fig. 4) for guiding on and off, and there are three different sealing rings, i.e.

outer sealing ring 112, middle sealing ring 113 and inner sealing ring 114, inside the bottom of the cap body 11 to enable the container to be made airtight and leakproof; a connecting band 12, disposed at the middle portion, of which tearable film rings 115 on the upper and lower sides are connected to the cap body 11 and a tamperproof snap ring 13, a tab 121 at one end of the connecting band 12 is designed to tear off the band 12 so as to separate the cap body 11 from the snap ring 13, and there is a breaking between the two ends of the connecting band 12; and a tamperproof snap ring 13, disposed at the lower end, of which the inner side is provided with four start (or a plurality of starts) snap hooks 131 with equal size, and interval to mutually catch the container neck snap hook 23 and container neck stop block 25 so that the cap 1 cannot be twisted to open prior to tearing off the connecting band 12.

As shown in Fig. 5 and 6, the actions needed to close the container mouth are as follows; firstly the cap 1 is placed on the mouth of the container, the four start cap screw thread 111 on the annular inner wall cap body 11 are disposed on the container neck screw thread 22, and the tamperproof snap ring 12 is disposed on the container neck snap hook 23; next, the cap 1 is twisted in a clockwise direction, the four start cap screw thread 111 sliding down to the next container neck screw thread 22 along the four notches b (as shown in Fig. 4) between the four start container neck screw thread 22, and at the same time, through the vertical pressure resulted from the cap screw thread 111 sliding down, the tamperproof snap ring 13 spreads along the inclined plane of container neck snap hook 23 to press down and slide into the recess c between the container neck snap hook 23 and a protective ring 24; and then the four start (or a plurality of starts) cap snap hook 131 on the tamperproof snap ring 13 and the container neck snap hook 23 vertically and tightly catch each other, and the cap snap hook 131 horizontally catches the four start (or a plurality of starts) container neck stop block 25 (as shown in Fig. 4) so that the cap 1 cannot be twisted to open before tearing off the connecting ring 12.

When the cap screw thread 111 slides down, the outer sealing ring 112 and middle sealing ring 113 move down vertically to press and clamp the two sides of container mouth 21 tightly to provide a leakproof and airtight seal.

As shown in Fig. 7, when it is desired to open the cap 1, firstly the tab 121 is held on the connecting band 12 and then the connecting band 12 torn clockwise so as to release the cap body 11 from the tamperproof snap ring 13 and to make the cap 1 movable; then the cap body 11 is twisted in a counter-clockwise direction, the cap screw thread 111 moves upward along the container neck screw thread 22 to restore their original position, namely, being disposed on the container neck screw thread 22, so that the cap body 11 may be easily opened; the tamperproof snap ring 13 is left in the recess c between the snap hook 23 and the protective ring 24 so as to decorate the appearance of the container.

As shown in Fig. 8, the outer sealing ring 112, middle sealing ring 113 and inner sealing ring 114 of cap body 11 tightly contact the three points, i.e. container mouth outer edge angle x, a container mouth surface y and container neck bore z of a blow moulded container 3 to form a triple sealing action; the tamperproof construction and the screw thread portion in keeping with the cap 1 of both the blow moulded container 3 and the injection moulded container 2 are the same except the sealing construction thereof.

The present invention offers a twistable, self-sealing and tamperproof container cap which is of plastics and able to achieve the purpose of tamperproof, leakproof and airtightness. No additional attachment is needed and the cap only needs to be twisted to close or open the container mouth.

Claims

CLAIMS:

1. A twistable, self-sealing and tamperproof container cap on an annular inner wall of which is provided a plurality of mutually indented threads for engagement with corresponding screw threads on the neck of a container to which the cap is to be fitted, annular sealing rings being provided within the base of the cap, a tamperproof snap ring, being disposed at the lower edge of the cap the inner side of which is provided with a plurality of cap snap hooks, and a connecting ring, disposed in a middle portion of the cap, tearable rings being connected to the cap body and the tamperproof snap ring, whereby pulling tears off the connecting ring so as to separate the cap body from the tamperproof snap ring.

2. A twistable, self-sealing and tamperproof container cap substantially as herein described with reference to and as illustrated in any one of the accompanying drawings.

3. A container including a cap as claimed in claim 1.