This application was originally filed as international application PCT/NL99/00498 on Aug. 4, 1999.
The present invention relates to a closing valve for a container or a pipe system, comprising a closing jacket connectable to an opening in the container or forming part of the container, which closing jacket is provided on the inside with a narrowed and a widened portion, and a valve part movable in this closing jacket with a closing element and a clamping element rigidly connected therewith and extending in the closing jacket, which clamping element is provided on at least the outside with a thickening which, when the passage through the closing jacket is sealed by the valve part, is in contact with the widened portion in the closing jacket, while, furthermore, a head part movable back and forth in the closing jacket, optionally to be put into circulation apart, is provided, by means of which the valve part can be moved with respect to the closing jacket such that the passage therethrough can be released and/or closed.
Such a container may be a cardboard, metal or plastic packing as well as a compressible plastic bag, a glass, bottle and the like. The container is suitable for gaseous products as well as all kinds of liquids, optionally mixed with gas, both under pressure and under vacuum, highly viscous substances, such as puree, and further granulates, granular material, etc. The closing valve may also be included in a pipe system.
A closing valve as described in the opening paragraph is known from WO94/29215. In said document a thickening at the outside of the clamping element has the function to lock a head part with a tube relative to a valve part in the form of a closing plug. Because said thickening only temporarily rests against the edge of the thickening, for a short time a counterforce, necessary to lock the head part with the tube relative to the valve part, is exerted. By pushing the close jacket in the first instance said thickening meets the edge of the narrowed part of the closing jacket. At that moment the head part with the tube is still free removable (FIG. 2). When the head part with the tube is pushed further, the head part is locked in the xe2x80x98valvexe2x80x99 part because the edge of the valve part engages a groove between the head part and the tube (FIG. 3). When thereafter the head part with the tube is pushed further again, said thickening being pressed along the edge of the narrowed part of the closing jacket, the container is fully opened as then the outlet opening in the tube is located in the container (FIG. 4). In the latter position there is no locking between the valve part with the head part on the one hand and the closing jacket at the other hand, so that the position of these parts relative to each other is not determined any longer and not adjustable at all. As the valve element is in the form of a closing plug, the outlet opening is brought in the tube, with the risk that when the tube is wrenched off the valve part, the valve part will fall into the container, which then cannot be closed again.
The object of the invention is to provide for such a container an efficiently and inexpensively producible closing valve, via which the container can be easily filled and closed and the substances contained therein can be easily poured out or pressed or sucked out of the container, and by means of which closing valve the above problems are obviated.
To this end, according to the invention the closing valve is characterized in that, the thickening on the outside of the clamping element is located near the upper part of the clamping element, such that, when the passage through the closing jacket is released, the thickening on the outer side of the clamping element is brought into the narrowed portion of the closing jacket, as a result of which the clamping element reaches a position in which it is engaged by the head part.
The closing vale is therefore opened by pushing down the valve part by means of the head part, while by pulling up the head part, which as then engaged the clamping element, the valve part is taken along and the closing valve is gradually closed. The head part can therefore also be designed as a tap and brought into several positions and optionally fixed in these positions with respect to the closing jacket, so that gradually opening and closing the passage by the closing jacket becomes possible.
Although it is sufficient for specific uses to only open the container by means of the head part, in which connection it is not important that the valve part lands in the container, it is important for many other uses that the head part is provided with locking means for preventing the valve part from being pushed completely out of the closing jacket.
As appears from the foregoing, the closing valve, in its basic structure, is composed of only three easily producible parts: a closing jacket, a valve part and a head part; moreover, an inexpensive final product can be obtained by, for instance, injection molding these parts from some hard plastic. Of course, it remains possible that the closing jacket forms part of the container and/or that the head part forms part of a draw-off tap.
For many uses the head part will be provided with a throughbore which, at the lower end, is in open communication with the inside of the closing jacket, so that, when the closing valve is opened by pushing in the head part, an open communication with the atmosphere results, to which optionally other filling, outlet or pouring means or the like can be connected. In a favorable embodiment the head part is provided with a widened upper part which, when the valve part is pushed out of the closing jacket at least partially, seals the upper side of the closing element.
In addition to the three above basic parts, further parts may be provided, such as a sealing element to be arranged between the closing jacket and the head part, in particular an O-ring, to enable a fluid-tight closure. Further sealing elements, for instance around the peripheral edge of the closing element, may be provided; these sealing elements, however, may also be formed by, for instance, plastic edges forming part of the relevant components.
Although the clamping element may be cylindrical, while an annular thickening may be provided on the outside as well as on the inside, it is difficult to push in such a clamping element on all sides; anyhow, the clamping element then needs to be rather easily deformable. It is better when the clamping element is finger-shaped, with each of the finger-shaped parts on the inside and outside being provided with a thickening. It is indeed easier to push in the individual fingers. The thickening on the inside then serves to facilitate engagement by the head part.
When the container is formed by an easily compressible packing, such as, for instance, a plastic bag to which the closing valve as hitherto defined is connected, and furthermore, this easily compressible packing is arranged in an outer packing which is not compressible or is relatively difficult to compress, the closing valve needs to be provided with additional means. To this end, according to the invention a collar element connectable to an outer envelope or forming part thereof is provided, which collar element fits around the closing jacket, while between the outer circumferential surface of the closing jacket and the inner circumferential surface of the collar element gas supply channels, in particular air supply channels, are provided, which are opened when releasing the passage in the closing jacket. This has the advantage that gas can flow into the space between the inner packing, this is the easily compressible packing, and the outer packing, so that, when a pump is connected to the head part, the inner packing can be easily emptied by sucking, while the inner packing is compressed. Also, gas can be forcibly brought into the above space to enable the contents to be pressed out of the inner packing. This is important when the head part is formed by a filling head or a tapping head of, for instance, a tapping plant for beverages.