GB2301578A

GB2301578A - Valves for containers

Info

Publication number: GB2301578A
Application number: GB9511143A
Authority: GB
Inventors: Brian Pepper
Original assignee: BALL AND CO Ltd F
Current assignee: BALL AND CO Ltd F
Priority date: 1995-06-02
Filing date: 1995-06-02
Publication date: 1996-12-11
Anticipated expiration: 2015-06-02
Also published as: GB9511143D0; GB2301578B

Abstract

A valve (2 fig 1) integral with or attached to a container (4 fig 1) permits the flow of filling material into the container. The valve comprises a tubular valve body (18 fig 1) made up of two planar strips 22 and 24, inlet 16 and outlet 20 connected via a passage. The valve body has an area of weaker construction 28 (such as a crease or perforation) or a rigid structure in or on the surface of the valve body which permits the valve body to be folded into two sections when a cord 30 attached to one of the sections is drawn, thereby closing the passage between the inlet 16 and outlet 20. The cord may extend around the periphery of the valve body (fig 4) or at least partially though the passage in the valve body. The valve body may be flexible or resilient. The container may be a sack or a box. In place of the cord the valve may be provided with a return spring to close the passage.

Description

DESCRIPTION VALVES FOR CONTAINERS The present invention relates to valves for containers, and in particular, but not exclusively to containers such as sacks suitable for storing and conveying powdered or particulate materials.

The filling of a container, such as a sack, with a powdered or granular material is often inadequate because if the material is poured into the open end of the sack the material can disperse into the atmosphere and thereby contaminate the surrounding environment.

For this reason it is now conventional that the sack is substantially closed before it is filled and has in its wall, usually the top surface of the sack, a small orifice into which, during the filling process, the nozzle of a filling machine can extend in order to fill the sack by blowing the filling material directly into the interior of the sack.

However, once the sack has been filled, it is then necessary to seal the orifice in order that the contents cannot leak from the sack. It is known to heat seal such orifices, but such requires additional equipment and an extra step in the filling process leading to increased costs. Furthermore, the sealing process could damage the contents of the sack.

In order to overcome the above described problem, it is known to provide the sack with a flexible open ended tube which extends from the orifice into the interior of the sack, and thereby forms a valve. When the nozzle of the filling machine extends into the orifice, the tube is opened by the force of the material entering the sack. When the sack is full, the volume and/or weight of the material in the sack presses on the walls of the tube to close the tube and thereby the orifice. However, it has been found that the volume and/or weight of the contents of the sack is not sufficient to completely close the tube and leakages via the orifice occur, thereby contaminating the surrounding environment. This is a particular problem if the contents of the sack is a material, such as a cement based powder, which can be activated by contact with moisture in the air.

In order to overcome the above described problem, the known system has been modified whereby the end of the tube remote from the orifice is closed and the wall of the tube is provided with a plurality of slits. During the filling process, the force of the material entering the sack forces open the slits so that the material can enter the sack. When the sack is full, the weight and volume of the contents pressing on the tube seals the slits. It has been found that this system has the disadvantage that because one end of the tube is closed, the filling material can effectively back up in the tube and block the nozzle of the filling machine. Furthermore, the contents of the sack do not provide an effective seal for the tube and the contents can seep through the slits and out through the orifice.

It is an object of the present invention to provide a valve for containers which overcomes or alleviates the above described drawbacks.

In accordance with one aspect of the present invention there is provided a valve for a container, which in use permits the flow of a filler into the container, the valve having a valve body, an inlet, an outlet connectable to the inlet via a passage through the valve body, and a valve closure means which in use can fold the valve body in order to close the passage between the inlet and the outlet.

This has the advantage that a substantially sealed container can be filled with the inlet of the valve providing the aforementioned orifice to the container and the valve can be closed simply by folding the passage way between its inlet and outlet.

Preferably, the valve closure means is a weakened area in the surface of the valve body or a rigid structure provided in or on the surface of the valve body. This has the advantage of providing a simple means for folding the valve body to close the passage.

The weakened area could be a crease or perforation in the valve body. The rigid structure could be a metal strip or a surface on the container about which the valve body can be folded.

Preferably, the valve closure member comprises a cord attached to the valve body. This has the advantage that by a simple means the valve body can be folded by drawing on the cord.

By way of example only, specific embodiments of the present invention will now be described with reference to the accompanying drawings, in which: Fig. 1 is a partial illustration of a sack including a cut-away section to illustrate in the interior of the sack a valve constructed in accordance with one embodiment of the present invention; Fig. 2 is a detail of the valve of Fig. 1; Fig. 3 is a detail of the valve of Fig. 2 with the valve in the closed position; and Fig. 4 is a detail of the valve constructed in accordance with a second embodiment of the present invention.

A valve 2, constructed in accordance with one embodiment of the invention is shown in-situ in a sack 4 in Fig. 1. The top end of the sack 4 shown in the illustration is substantially closed by folding over the edges of the sac at 6,8,10,12. The edges 6,8,10,12 are fixedly closed by a sticky strip 14 to leave an inlet 16 to the sack 4. The inlet 16 is the inlet to the valve 2 and a flexible open-ended tube 18 or valve body extends from the inlet 16 to the interior of the sack 4.

As best illustrated in Figs. 2 and 3, the end of the tube 18 or valve body remote from the inlet 16 forms the outlet 20 of the valve 2 in the sack 4. The valve body 18 comprises two substantially planar strips 22,24 of unequal length but of substantially equal width which are joined together along their adjacent longitudinal edges to form the substantially oblong valve body 18. The end of the valve body 18 remote from the inlet 16 forms the valve outlet 20.

The strip 22 is longer than the strip 24 and the additional length forms a flap 26. The valve body 18 has a peripheral crease 28 adjacent the outlet 20. A cord 30 extends from the exterior of the sack 4 through the inlet 16 into the interior of the valve body 18 and out through a through-bore 32 in the strip 24 into the interior of the sack 4. The end 34 of the cord 30 within the sack is attached to the flap 26.

The valve is closed by drawing the cord 30 away from the sack 4, thereby folding the outlet end 20 of the valve 2 via the crease 28 and sealing the outlet 20 with the portion 36 of the valve body 18 and the flap 26 (as best illustrated in Fig. 3).

In the second embodiment of valve illustrated in Fig. 4, the construction of the valve 2 differs from that shown in Figs. 1 to 3 in that the strips 22,24 are of substantially equal length and the cord 30 does not pass through the interior of the valve body 18, but instead enters the sack 4 via a through-bore 38 in the sack 4 and the end 34 of the cord 30 extends around the periphery of the valve body 18 at a location adjacent the outlet 20. When the cord is drawn out of the sack 4, its end 34 pulls the outlet 20 and the valve 2 is folded at the crease 28 such that the body 18 is folded back on itself and thereby closes the outlet 20.

The valve 2 is operated as follows: The sack 4 is filled by placing the nozzle of a filling machine (not illustrated) into the inlet 16 and thereby into the valve 2. The nozzle sprays filling material directly into the sack 4 via the valve body 18. When the sack 4 is full, the cord 30 is drawn and the valve is closed by folding the outlet 20 down onto the valve body 18. In order to draw the cord 30, the end 40 of the cord 30 could be pulled manually, or means could be provided to automatically drawn the cord 30. For instance, means could be provided on the filling machine which draws the cord 30 when the nozzle is withdraw from the inlet 16. The cord 30 could be provided with means, for example a knot 42 which prevents the cord from being drawn completely into the sack.

A cord has been described as the closing means for the valve, but other means could be provided, such as a return spring whose spring-force is sufficient to close the outlet of the valve once the sack is full.

The crease 28 could be a prefold in the valve body 18, or a perforation. The valve could be formed from the sacking, ie. the material of the container by forming the valve out of the fabric of the sack. Or the valve could be an additional component to the sack whereby the valve body is adhered to the flaps of the top end of the sack. The valve could be constructed from different material to the sack to thereby improve the flexibility and the ability of the valve body to fold. A sack has been described, but the valve could be inserted into other types of container, such as a box. The valve body can be resilient to allow the body to expand during the filling process.

Claims

1. A valve for a container, which in use permits the flow of a filler into the container, the valve having a valve body, an inlet, an outlet connectable to the inlet via a passage through the valve body, and a valve closure means which in use can fold the valve body in order to close the passage between the inlet and the outlet.

2. A valve as claimed in claim 1, wherein the valve closure means is an area of weakened structure in the surface of the valve body which divides the body into two sections.

3. A valve as claimed in claim 2, wherein the valve body is substantially tubular and the weakened area is a crease or perforation about the circumference of the body.

4. A valve as claimed in claim 1, wherein the valve closure means is a rigid structure on or in the surface of the valve body which divides the body into two sections and permits the folding of one section with respect to the other section.

5. A valve as claimed in any one of claims 2 to 4, wherein the valve closure means also comprises a cord attached to one of said sections of the valve body.

6. A valve as claimed in claim 5, wherein the cord extends around the periphery of the valve body.

7. A valve as claimed in claim 5 or 6, wherein the cord extends at least partially through the passage in the valve body.

8. A valve as claimed in any of claims 2 to 7, wherein one of the sections of the valve body comprises a flap.

9. A valve as claimed in any one of the preceding claims, wherein the valve is integral with a container or has means for attachment to a container.

10. A valve as claimed in claim 9, wherein the container is a sack.

11. A valve as claimed in any one of the preceding claims, wherein the valve body is resilient.

12. A valve as claimed in any one of the preceding claims, wherein the valve body is flexible.

13. A valve constructed and adapted to operate substantially as hereinbefore described, with reference to, and as illustrated in, the accompanying drawings.