GB2318114A

GB2318114A - Two piece dispensing bottle cap

Info

Publication number: GB2318114A
Application number: GB9621201A
Authority: GB
Inventors: Dean Walding
Original assignee: Dragon Plastics Ltd
Current assignee: Dragon Plastics Ltd
Priority date: 1996-10-11
Filing date: 1996-10-11
Publication date: 1998-04-15
Anticipated expiration: 2016-10-11
Also published as: GB9621201D0; GB2318114B

Abstract

A two piece cap for a bottle has an outer annular cap 31 with a central aperture 33 screw threaded to an inner cap 14 with a central spigot 17. Rotation of the outer cap relative to the inner cap causes the outer cap to move between a sealed position in which the spigot blocks the aperture, and an open position in which the aperture is spaced from the spigot so that contents may be dispensed from the bottle. The inner cap may have a tapering annular projection 19 which sealingly engages the inner surface of the bottle's outlet. The outer cap may have a depending annular lip 34 around its aperture which seals against the spigot, and an annular inner wall 36 which seals against an upstanding annular wall 22 on the inner cap. The spigot may be connected to the inner cap via a flexible diaphragm (not shown) with at least one aperture 18. Rotation of the outer cap may be restricted to 120 degrees by end stops (not shown). In use, the inner cap may be attached to a bottle by screw threads 15.

Description

BOTTLE CAP This invention relates to a cap for a bottle, and particularly to a two-piece cap which can be manipulated to provide an opening without removing the cap from the bottle.

Two-piece caps are known, and generally comprise an inner cap screwed to the neck of a bottle, and an outer cap retained on the inner cap but rotatable therewith to bring apertures of the inner and outer cap into alignment. When such apertures are aligned the contents of the bottle can be poured out. Such caps are well-known for containers of flowable granular material such as salt.

In the case of liquid contents, the cap assembly must have means of sealing the apertures so as to prevent leakage of material. The present invention provides a more effective seal than has hitherto being provided.

According to the present invention there is provided a cap assembly for a bottle, the cap assembly comprising an inner cap adapted to be secured to the opening of a bottle, and an outer cap screw-threaded to the inner cap whereby relative rotation causes the inner cap to move axially of the outer cap in the direction of the axis of rotation, the outer cap having a central aperture on said axis, and the periphery of said aperture defining a sealing lip for engagement with an upstanding plug of the inner cap, axial movement of the outer cap away from the inner cap defining an annular opening between the periphery of said aperture and said plug, the opening communicating with the interior of the bottle in use. The inner cap is typically secured to the bottle by means of screw-threads, and when tightly engaged on the bottle, is secure against relative rotation thereto. Alternatively the inner cap may be a snap-fit, and may further include an abutment to hold the inner cap secure against rotation relative to the bottle. The inner cap may include a flexible annular ring depending therefrom for engagement with the mouth of the bottle neck; such a ring provides an effective seal, and may be tapered to ensure easy entry into the bottle mouth.

Relative rotation of the outer cap with respect to the inner cap may be limited by fixed stops; in a preferred embodiment the relative rotation is limited to 900.

Secondary stops may retain the outer cap at the end of its permitted travel.

The plug of the inner cap is preferably connected to the outer portion thereof by a relatively thin diaphragm.

The diaphragm has necessary apertures to permit material to flow from the bottle in use, and also gives a degree of resilience to the plug in the axial direction.

The periphery of the aperture in the outer cap may be tapered in order to provide a relatively thin flexible lip, and the plug may be arranged to protrude, or at least be level with the outermost part of the lip.

The sealing portion of the lip may extend over a relatively wide band of the plug so as to give an effective seal. In this respect the outer cap may include a secondary lip extending axially inwardly of the outer cap, and engageable with a tapered portion of the plug.

Other aspects of the invention will be apparent from the following description of a preferred embodiment shown by way of example in the accompanying drawing which is a partially cut-away view of a cap secured to a bottle neck.

In the drawings a bottle 11 has an upstanding neck 12 with an external screws-thread 13. Such a bottle is conventional and may be moulded from glass or plastics material.

An inner cap 14 has an internal screw-thread 15 for engagement with the thread 13.

The transverse portion of the inner cap comprises a diaphragm 16 and an upstanding annular plug 17. The diaphragm includes apertures 18 to allow the passage of material from the interior of the bottle. A depending lip 19 engages the mouth of the bottle to provide an effective seal, and is, as illustrated, tapered to facilitate easy insertion. The inner cap is typically moulded of a resilient plastics material, and the lip 19 is thus relatively flexible. The plug 17 narrows towards the top thereof at a slight angle of about 100 to the vertical. The plug has a flat top which is linked to the side wall by a straight portion at an angle of about 450. The plug itself is hollow to facilitate moulding.

The external periphery of the upper cap extends above the diaphragm, and has a partial external thread 21 with a relatively large pitch.

The outer cap 31 envelops the inner cap and has an internal thread 32 for engagement with the thread 21.

Relative rotation of the inner cap with respect to the outer cap thus causes significant axial separation for a small degree of rotation, and typically the relative rotation is limited to 900 by internal thread stops (not illustrated).

The top of the outer cap extends inwardly and upwardly on a gentle curve to a central axial aperture 33. The periphery of the aperture tapers to form a sealing lip which, as illustrated, engages the plug 17. An annular inward extension 34 increases the width of the sealing land and acts as a wiper to ensure that at least a portion of the sealing land is wiped prior to final closure.

The outer cap is secured on the inner cap by a conventional inwardly extending ring 35 which snaps over a corresponding outwardly extending ring 22 of the inner cap.

These rings may in fact constitute one rotational end stop, the other being constituted by sealing engagement of the outer cap with the plug 17.

The outer cap includes an inwardly extending lip 36 for engagement with the inner periphery of the annular upward extension 22 of the inner cap, thereby to give effective sealing.

The outer cap is milled at 37 to provide a grip.

In use the outer cap is snapped over the inner cap, and the assembly is screwed onto the bottle neck. Relative rotation of the inner cap and outer cap is limited, and thus rotation of the outer cap applies the inner cap to the neck of the bottle. The inner lip 19 seals the inner cap to the bottle, and the lip 36 seals the inner cap to the outer cap.

Relative rotation of the outer cap with respect to the inner cap in the opening direction (anti-clockwise) causes the inner cap to move to the position shown in dotted lines in the accompanying drawing. Material can be poured out of the bottle through the apertures 18 and 33 as indicated by the arrows. The outer cap is made of a resilient plastics material, and the flexibility of the upper wall thereof ensures a fluid type seal on the plug 17. A separate stop can be provided in the closing direction to limit the resilient force of the sealing lip on the plug 17.

In order to transmit sufficient torque to the inner cap when first screwed onto the bottle neck, the underside of the outercap and the upper edge of extension 22 may include co-operating formations in order to give a direct drive in the 'on' direction. Such formations may typically comprise conventional ratchet teeth engageable to transmit drive in the clockwise direction, and can reduce the load on the normal rotational end stops.

Such a cap assembly provides an excellent seal on the bottle since the inner cap is immovable after first application. Furthermore the cap assembly is relatively easily adapted to accommodate a tamper evident seal on the lower edge thereof.

Claims

CLAIMS:

1. A cap assembly for a bottle, the cap assembly comprising an inner cap adapted to be secured to the opening of a bottle, and an outer cap screw-threaded to the inner cap whereby relative rotation causes the inner cap to move axially of the outer cap in the direction of the axis of rotation, the outer cap having a central aperture on said axis, and the periphery of said aperture defining a sealing lip for engagement with an upstanding plug of the inner cap, axial movement of the outer cap away from the inner cap defining an annular opening between the periphery of said aperture and said plug, the opening communicating with the interior of the bottle in use.

2. A cap assembly according to Claim 1 wherein the inner cap has a depending annular projection engageable against the inner wall of the mouth of a bottle, the projection constituting a fluid seal.

3. A cap assembly according to Claim 2 wherein said projection is tapered.

4. A cap assembly according to any preceding claim wherein the permitted relative rotation between the inner and outer caps is limited to less than 1200 by end stops.

5. A cap assembly according to any preceding claim wherein the inner cap is connected to said plug by a radially extending resilient diaphragm, the diaphragm permitting movement of said plug in a direction axial of the cap, and the diaphragm having one or more apertures therein.

6. A cap assembly according to any preceding claim wherein the sealing lip is tapered.

7. A cap assembly according to any preceding claim wherein the sealing lip has an annular extension radially outward of the tip thereof and extending substantially axially and inwardly of the outer cap.

8. A cap assembly according to Claim 7 wherein said plug has a planar top face substantially perpendicular to the rotational axis thereof, a lower side wall at an angle of less than 300 to said axis, and an upper side wall between the lower side wall and the top face at an angle of about 450 to said axis.

9. A cap assembly according to any preceding claim wherein said inner cap has an annular upstanding wall, and said outer cap has an annular depending wall engageable with said upstanding wall to provide a fluid seal therebetween.

10. A cap assembly substantially as described herein and as illustrated in the accompanying drawings.