Abstract:
An apparatus for distributing a filling product includes a filling valve for liquids, a closure element, and an actuator. The filling valve is configured for opening and closing a distribution or flow opening by linearly displacing the closure element. The valve comprises a valve chamber in which the closure element is arranged. The actuator, which is arranged within a constant volume arranged within the valve chamber, influences movement of the closure element.

Description:
RELATED APPLICATION 
     This application is the national stage entry under 35 USC 371 of PCT/EP2012/001623, filed on Apr. 14, 2012 which, under 35 USC 119, claims the benefit of the priority date of German application DE 10 2011 018 479.1, filed on Apr. 21, 2013, the contents of which are herein incorporated by reference. 
     FIELD OF INVENTION 
     The invention relates to valves for liquid, and in particular, to ways to prevent valves from dripping. 
     BACKGROUND 
     A valve used for liquid often has a gas lock that prevents the valve from dripping when a closure element closes the valve. 
     In such a filling valve, the closure element is normally attached to a tappet that moves up and down. To open and close the valve, one normally moves the closure element up and down. 
     Within the filling valve is a valve chamber. The valve tappet and the closure element are both in this valve chamber. At its bottom end, the valve chamber has an opening for allowing filling product to leave it. In operation, the valve chamber is completely filled with filling product. 
     To close the filling valve, one moves the closure element from its open position to its closed position. This involves moving the valve tappet down. This means that more of the tappet&#39;s length will be inside the valve chamber. Naturally, this leaves less room for liquid in the chamber. 
     As noted above, the valve chamber is completely filled with filling product. This means that when the valve tappet moves down, it displaces liquid. This liquid has to go somewhere. Typically, this displaced liquid cause the gas lock to fail. As a result, the valve drips. In some cases, the displacement also causes a noticeable surge in pressure. This leads to even more dripping. 
     SUMMARY 
     The invention provides a valve for liquid, and in particular, a filling valve for beverages. The valve avoids or at least significantly reduces pressure surges and displacement of liquid in the valve chamber that occur as a result of moving mechanical parts inside the valve chamber. 
     In one aspect, the invention features a valve that avoids volume changes and pressure surges. This is achieved by no longer arranging the valve tappet directly in the valve chamber. As a result, the valve tappet is no longer in direct contact with the liquid. 
     Instead, the valve tappet is arranged within a hollow body that, in operation of, has a constant volume. The hollow body is arranged in the valve chamber. As a result, movement of the valve tappet is transferred to the actual valve cone in a way that avoids changes in the volume available to liquid within the valve chamber. 
     In another aspect, the invention features a valve having a linearly-moving closure element, for example a filling valve for liquid media, in which closing or opening is carried out without a change in the volume available for liquid in the valve chamber. 
     In some embodiments, the constant volume is formed from at least one flexible, elastically deformable element. In these embodiments, the elastic deformation does not result in any change in the volume taken up by the deformable element. 
     Another aspect of the invention features an apparatus for distributing a filling product. Such an apparatus includes a closure element, a liquid-dispensing filling valve configured for opening and closing an opening by linearly displacing the closure element, and an actuator, arranged within a constant volume. The actuator influences movement of the closure element. The valve includes a valve chamber in which the closure element and the constant volume are both arranged. 
     Some embodiments further include an elastically deformable element. In these embodiments, the constant volume is formed from the elastically deformable element. Among these are embodiments in which the elastically deformable element comprises a bellows. 
     Other embodiments include a rigid hollow body that forms the constant volume. 
     Yet other embodiments further include a fastening device that is mechanically connected to the actuator so that it transfers movements of the actuator. Among these embodiments are those in which the actuator and the fastening device are magnetically connected with each other. 
     In other embodiments, the constant volume comprises first and second bellows arranged in series. During operation of the valve, the liquid remain outside the first and second bellows. 
     In yet other embodiments, the valve chamber has an annular cross-section along at least a portion thereof. 
     Further embodiments include those in which the valve chamber comprises a first extent and a second extent, with the first extent having an annular cross-section and the second extent having a circular cross-section. 
     In yet other embodiments, the actuator moves relative to the constant volume. 
     In another aspect, the invention features a method for opening or closing a valve&#39;s opening to control flow of a liquid. In this method, the valve has a valve chamber that is filled with liquid. It also has a constant volume structure within the valve chamber. Opening and closing the valve includes moving an actuator that is disposed inside the constant volume structure relative to the constant volume structure. Moving this actuator linearly displaces a closure element. 
     In some practices of the invention, the valve is a filling valve for filling of beverages, whereas in others, it is a pipeline valve. 
     As used herein, the term “container” refers to cans, bottles, tubes, and pouches whether made of metal, glass, plastic, and any combination thereof, as well as to other packing means suitable for filling liquid or viscous products for pressurized filling or for filling at ambient pressure. 
     As used herein, expressions such as “substantially” or “approximately” mean deviations from the respective exact values by ±10%, preferably by ±5% and/or deviations in the form of changes irrelevant to the function. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other features of the invention will be apparent from the following detailed description and the accompanying figures in which: 
         FIG. 1  shows a first embodiment of a valve for liquid according to the invention, 
         FIG. 2  shows a second embodiment of a valve for liquid according to the invention, and 
         FIG. 3  shows a valve for liquid, modified according to the invention, for opening or closing a through-opening. 
     
    
    
     DETAILED DESCRIPTION 
     In an embodiment shown in  FIG. 1 , first and second bellows  5 ,  6  form a constant volume inside a valve chamber  2 . The first bellows  5  has an upper end and a lower end. The upper end of the first bellows  5  attaches to the top of the valve chamber  2 . The lower end of the first bellows  5  connects to a height-adjustable sealing disk  7 . The second bellows  6  also has a top end and a bottom end. The top end of the second bellows  6  connects to a bottom of the sealing disk  7 . The bottom end of the second bellows  6  connects to a top of a base disk  8 . The base disk  8  forms a lower boundary of the constant volume. 
     The first and second bellows  5 ,  6  follow the movements of the sealing disk  7 . As the height of the sealing disk  7  changes during operation of the valve, volumes of the first and second bellows  5 ,  6  change. However, the sum of these volumes remains constant. 
     An outer circumference of the height-adjustable sealing disk  7  connects to a fastening device  10 . The fastening device  10  is shaped like a clamp or like a web. The valve tappet  9  connects the fastening device  10  to the actual closure element  3 . In the illustrated embodiment, the closure element  3  is a valve cone. 
     An actuator  12  is arranged inside the constant volume formed by the first and second bellows  5 ,  7 . This actuator  12  is connected to the sealing disk  7 . Because of this connection, the sealing disk  7  follows the movements of the actuator  12 . As a result, it is possible to cause the valve  1  to transition between an open and closed position without the side effect of changing the amount of volume available for liquid in the valve chamber  2 . This avoids displacement that can lead to pumping. 
     The constant volume does not need to be made from bellows. In some embodiments, the constant volume is formed from elastically deformable elements. An example of an elastically deformable element is a rolling membrane or a structure that is similar to a rolling membrane. 
     In another embodiment, which is shown in  FIG. 2 , a rigid hollow body  11  forms the constant volume. 
     Within the rigid hollow body  11  is an actuator  12  having first magnets arranged at a bottom thereof. Corresponding second magnets are arranged outside the hollow body  11 . The second magnets are supported within a guide in such a way as to be movable with low friction. 
     The first and second magnets on opposite sides of the hollow body  11  form a trouble-free magnetic coupling that enables the outer magnets to follow the movements of the inner magnets without delay and without undue deviations in length of travel. 
     A fastening device  10  connects the outer magnets to a valve tappet  9 . Preferably, the fastening device  10  is shaped like a web or clamp. The actual closure element  3  is connected to the fastening device  10 . In the illustrated embodiment, the closure element  3  is a valve cone. 
     As was the case for the embodiment shown in  FIG. 1 , the embodiment shown in  FIG. 2  permits opening and closing of the filling valve without changing the volume available for liquid within the valve chamber  2 . 
     The fastening device  10  is designed such that, as it moves up and down, it presents the lowest possible flow resistance. Accordingly, the fastening device  10  preferably comprises rod-shaped elements aligned with the movement direction. Any elements arranged transverse to the direction of movement are designed to aid the flow, for example, by being streamlined. 
     The proposed magnetic coupling between the actuator  12  and the fastening device  10  has been shown for a case in which a rigid hollow body provides the constant volume. However, a similar magnetic coupling can also be carried out when, instead, an elastically deformable element forms the constant volume. 
     In addition to the valves described above for filling a container with liquid of all kinds, in which a distribution opening is opened or closed, the present invention is also suitable for application in valves that open or close a passage opening. 
     An example of such a valve is an angle valve, as shown in  FIG. 3 . In the illustrated valve, a liquid medium enters the valve by flowing in an entry direction A and exits the valve by flowing in an exit direction B. 
     In the embodiment shown in  FIG. 3 , a constant volume is also arranged within a valve chamber  2 . This constant volume receives an actuator  12  and a sealing disk  7 . A fastening device  10  connects the sealing disk  7  to the valve tappet  9 . As a result, the fastening device  10  transfers the movement of the actuator  12  to the valve&#39;s closure element. The above arrangement avoids unwanted pressure surges generated by moving mechanical structures in contact with liquid, as is the case in a conventional valve. 
     A further example of a valve for liquid for opening or closing a through-opening is shown in  FIG. 1  in the form of a so-called slide valve. By means of the illustrated design, according to the invention, of such a slide valve, such devices can be constructed to be hygienic, i.e. easy-to-clean. 
     To date, in such valves for liquid, due to the glands used for these and the linear movement of the closure element, each actuation introduces particulate matter into the valve chamber. This particulate matter originates from either dirt or from abrasion of the glands. Moreover, the portions of the actuator  12  located within the gland could not be cleaned.