A threaded cap for a container

Abstract

 The present invention relates to a threaded cap with limited opening intended to be used in containers for liquids over a wide range of viscosity.
The cap is characterised essentially in that it is made out of one piece only (1) that screws on a bottle neck (2) and has orifices (4) for the liquid to pass and inner (5) and outer (6) sealing rings, which provide a sealing effect. The cap also has a rib (8) that allows the cap (1) to be screwed to the bottle pack (2) and to be unscrewed only up to a limit formed by a protrusion (7) on the bottle neck (2). Sealing is achieved whenever the top of the bottle neck obstructs the orifices (4) and opening whenever the cap is unscrewed up to the limit, leaving the orifices properly cleared.
This new cap, made preferably from plastic material is a very simple part in respect to its production, it is difficult to remove without destroying it which makes refilling impossible, it allows the easy incorporation of a tamper-proof ring and, due to its rigidity, it also allows normal handling during transport and storage.

Description

[0001] The present invention relates to a threaded cap for a container which can be only partially unscrewed, the cap being preferably made from plastic material, and in one piece only. In one position the cap provides a sealing effect and in a second position allows passage of the liquid to the exterior of the container onto which it has been screwed.

[0002] Until recently, known caps for containers which have to be squeezed to build up an internal pressure in order to drain viscous fluids, e.g. shampoo, are made from more than one piece, have relatively complex mechanisms, present complicated production problems, and do not always perform efficiently.

[0003] Having in mind a market that demands an easy but efficient operation, low production costs, a container which does not allow refilling, the inventor of the present invention conceived a cap that eliminates the disadvantages previously mentioned.

[0004] According to the present invention there is provided a threaded cap for a container comprising a single piece which screws onto the container neck, the cap being provided with one or more orifices for the passage of fluid and shaped such that there is an outer and inner sealing ring around the container neck which, when the cap is screwed onto the container completely, seal the container, the cap being further provided with means such that it can be only partially unscrewed. Because the new cap is made from one piece only it is very simple because, as it is made from plastic, it can be obtained from molds without unscrewing devices (the cap is designed in such a way that the use of adequate plastic material allows the part to be made from stripper type molds). The cap is attached to the bottle type container by an easy screwing operation and opens and closes by means of a small rotation. The cap cannot be removed from the container without destroying the system which in turn prevents the reutilization of the bottle (prevents refilling). The cap also allows the precise definition of the gap where the liquid must pass when the system is in its open position. This can prevent (depending on the liquid viscosity) the bottle from leaking when in an inverted position. The cap allows the easy incorporation of a tamper-proof ring, it can be functionally used for fluids with different viscosity, and due to its rigidity it allows normal handling during transport and storage.

[0005] A preferred embodiment of the present invention will now be described in detail, by way of example only, with reference to the accompanying drawings, in which:

Figure 1 represents a sectional view of a preferred embodiment of the present invention with the cap in a closed position,

Figure 2 represents a plan view through the sectional line shown in Fig. 1,

Figure 3 represents a sectional view of the preferred embodiment with the cap in an open position,

Figure 4 represents a plan view through the sectional line shown on Fig. 3.

[0006] As shown in the drawings, the cap (1) screws on the bottle neck (2) by means of the thread (3) existing on both. On the external side of the container neck a protrusion exists which is shaped such that it allows the rib (8) situated in the interior of the cap to pass over it during a forward screwing motion but will not allow it to pass on the reverse motion. This way the cap can only rotate on the unscrewing motion until the rib (8) in the cap collides with the protrusion (7) on the neck. This limiting system of protrusion-rib formation can be either above or below the threaded area (3). As can be seen on Fig. 1, when the cap is totally screwed the top of the container neck obturates the orifice(s) (4), that exist at the top of the cap (1). The sealing is then achieved not only through the sealing of the top of the container neck (2) against the cap (1), but also through the sealing arising from the side contact between the container neck and the outer sealing ring (5) and inner sealing ring (6) of the cap.

[0007] By unscrewing the cap (1) up to the allowed limit, the top of the container neck (2) moves away from the cap (1) clearing thus the orifice(s) (4). On the other hand, the inner sealing ring (6) of the cap (1) is of such a height, or has a localized reduction of its height, or a suitable configuration, which allows the unscrewing motion to remove the sealing effect on the container neck (2) allowing thus the passage of the liquid to the orifice(s) (4) and, consequently, to the exterior.

[0008] To restore the sealing effect it is necessary to screw the cap on again.

[0009] This cap easily allows the addition of an extra ring on its base which by interference with a suitable profile on the container neck makes the system tamper-proof until its first utilization. The first unscrewing motion, as it lifts and/or rotates the cap relatively to the container neck, will break the existing connections between the aforesaid ring and the cap. The tamper-proof ring can then become loose, which will allow it to fall, or can have be fitted such that it will remain on the container neck even after its connections to the cap have been broken.

[0010] The preferred embodiment shown in the attached drawings is not intended in any way to limit the model. Experts in the field can easily introduce several alterations to it but, nevertheless, they are included in the spirit of the following claims.

[0011] Several configurations are possible for the orifices in the form of slots having, for example, an inclination towards the center of the cap in such a way that fluid exits from the center of the cap. The orifices can vary in number and also in their disposition on the top of the cap. The size of the orifices depends mainly on the viscosity of the fluid packed into the container.

[0012] Depending on the cap configuration, the orifices can even be placed on the side wall of the cap instead of being on its top.

[0013] On the other hand, the system that limits the rotation of the cap over the container neck can have more than one set of protrusion-rib formations allowing a pre-set motion, preferably full turn or half turn. Also the outer sealing ring (5) may be omitted being simply replaced by the external wall of the cap. On the other hand, also the inner sealing ring can be replaced by different configuration, e.g. a recess.

[0014] Other modifications will be evident to the experts on the field such as different thread pitch, etc.

[0015] In accordance with the previous description it can be seen that this new cap is easily applied to the container neck unlike the already known similar caps which sometimes can present assembly problems. It is well known that in plastic container production it is in the neck where better dimension accuracy can be achieved. This fact allows the conventional production methods of these containers to guarantee the necessary characteristics to obtain a perfect sealing with this new cap.

Claims

1. A threaded cap for a container comprising a single piece which screws onto the container neck, the cap being provided with one or more orifices for the passage of fluid and shaped such that there is an outer and inner sealing ring around the container neck which, when the cap is screwed onto the container completely, seals the container, the cap being further provided with means such that it can be only partially unscrewed.

2. A threaded cap as claimed in claim 1 wherein the orifices are provided at the extreme end of the cap.

3. A threaded cap as claimed in claim 1 or claim 2, characterised in that the cap is provided inside with one or more ribs that allow its complete screwing onto the container neck and its unscrewing up to a point defined by a limit made from one or more protrusions on the container neck.

4. A threaded cap in accordance with any of claims 1 to 3, characterised in that it is only possible preferably to unscrew the cap up to a half turn, providing a relative displacement of the cap and container to allow passage of fluid through the orifices in the cap.

5. A threaded cap in accordance with any of claims 1 to 4, characterised in that the orifices are slot shaped, and are dimensioned in accordance with the viscosity of the fluid packed into the container.

6. A threaded cap in accordance with the previous claims, characterised in that the screwing motion of the cap restores its sealing effect.

7. A threaded cap in accordance with claim 1, characterised in that the sealing rings on each side of the upper side of the container neck provide thus an efficient sealing effect.

8. A threaded cap in accordance with the previous claim, characterised in that the inner sealing ring has a height, or a localized reduction of its height, or an adequated configuration in such a way that it allows the unscrewing motion of the cap to destroy the sealing effect that it exerted on the container neck.

9. A threaded cap in accordance with the previous claims, characterised in that it will not allow its removal without destroying its working system and allows the easy integration of a tamper-proof ring.

10. A threaded cap and a container, the cap comprising a single piece which screws onto the container neck, the cap being provided with one or more orifices for the passage of fluid and shaped such that there is an outer and inner sealing ring around the container neck which, when the cap is screwed onto the container completely, seal the container, the cap being further provided with means such that it can only be partially unscrewed.

11. A threaded cap for a container substantially as herein described and as illustrated in the accompanying drawings.

12. A threaded cap and a container substantially as herein described and as illustrated in the accompanying drawings.

Drawing