Abstract:
A discharge valve for a container ( 1 ) containing a flowable medium, having a movable valve part ( 10 ) which, in a rest position, keeps an outlet closed, has at least two open positions with different outlet cross sections.

Description:
BACKGROUND OF THE INVENTION 
   Field of the Invention 
   The invention relates to a discharge valve for a container containing a flowable medium, having a valve part which is movable into an open position and, in a rest position, keeps an outlet closed, and to a container provided with a discharge valve of this type. 
   Discharge valves of this type are arranged in a closure element of the container opening into which they are inserted and fixed generally after filling has taken place. In order to be able to remove the container contents in particular portion by portion, the valve part is moved into the open position, for which various possibilities are provided. 
   The valve part can be rotated. WO 99/18026 or U.S. Pat. No. 5,715,877 shows one example of a metering device with a rotatable valve part. 
   The valve part can be displaced axially. WO 93/13009 shows one example of a metering device with an axially displaceable valve part. 
   The valve part can be rotated and displaced axially. 
   WO 01/28914 shows one example of a metering device with a valve part of this type. 
   When the valve is opened, a certain quantity of medium flows out, with the size of the opening cross section depending on the opening time, for example on the duration of actuation of a corresponding handle. 
   SUMMARY OF THE INVENTION 
   The invention now provides a discharge valve by means of which it is optionally possible for at least two different quantities to be removed from the container per unit of time by the discharge valve having at least two open positions with different outlet cross sections. 
   A discharge valve is preferably assigned one actuating handle per open position, so that the valve part is transferred into the particular open position through selection of the handle. 
   Each of the three abovementioned possibilities is conceivable for the transfer into the open positions. If the container is inserted upside down into a metering device, then provision is made, in a preferred embodiment, for the valve part to be height-adjustable, and for the two open positions to be provided one above another. During the height adjustment of the valve part, the individual open positions are therefore reached successively, the sequence not being of importance per se. However, provision is preferably made for the valve part, after a short opening travel, to open up a small outlet cross section in the first open position and, after a longer opening travel, to open up the larger outlet cross section in the second open position. 
   Each outlet cross section is determined in particular by discrete outflow openings which are provided successively in the opening travel. This affords the advantage that the quantity emerging from the container is not dependent on the precise handling of the valve part, with the result that inaccuracies of any type, for example in the production of the discharge valve, in the production of the container, in the actuating mechanism of the metering device, etc., do not have any effect on the metered quantity. The particular travel length until the corresponding outflow opening is opened up is therefore noncritical. 
   In the thoroughly conceivable possibility of the outlet cross section being enlarged continuously by the movement of the valve part, this clearance is not provided. In such an embodiment an adjusting device is then preferably provided. 
   When a first outflow opening is opened in the first open position, and a second outflow opening is opened in the second open position, two different possibilities are provided. Firstly, the first outflow opening can remain open, so that the larger outlet cross section is produced from the sum of the two outflow openings, in which case the second outflow opening can be smaller, identical or larger, since it always complements the first outflow opening. 
   In the second case, the first outflow opening is closed again when the second is opened. In this case, the second outflow opening is larger if, as preferably specified above, the second outflow opening is to have the larger outlet cross section, and smaller, if the first outflow opening is to have the larger outlet cross section. 
   One preferred embodiment of the discharge valve makes provision for the discharge valve to have a hollow-cylindrical closure element which can be inserted into the valve opening and in which the movable valve part is sealingly guided in the manner of a piston, and for the outlet openings to be formed by at least two axially offset holes in a side wall of the closure element, which holes, during the stroke of the valve part, connects the container interior to the surroundings in terms of flow. If the container does not have flexible, but rather essentially stiff walls, then provision is furthermore made for the valve part to have an axial air inlet duct. 
   Two exemplary embodiments of the invention are described in more detail below with reference to the figures of the attached drawing, without being limited thereto. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is an axial section through a discharge valve inserted into an upside-down container, in the closed or rest position, 
       FIG. 2  shows the discharge valve in a first open position, 
       FIG. 3  shows the discharge valve in a second open position, 
       FIG. 4  shows the discharge valve in a third open position, and 
       FIGS. 5 and 6  show axial sections according to  FIGS. 1 and 4  through a second exemplary embodiment. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   A discharge valve  2  has a closure element  4  which is matched to the cross section of the opening of a container  1  and, after the filling of the container  1  with a flowable medium, for example a detergent or disinfectant concentrate, is inserted into the container opening and fixed permanently, for example bonded or welded. The closure element  4  is provided with a tubular section  5  which protrudes into the interior of the container  1  and merges via a converging guide part  3  into a tubular section  6  which has a smaller diameter than the tubular section  5 . 
   In the exemplary embodiment shown, the tubular section  5  has three outflow openings  7 ,  8 ,  9  arranged one above another. In the closed position according to  FIG. 1  or  5 , a piston-like valve part  10  extends in an outermost position, in which a connection in terms of flow between the interior of the container  1  through the outflow openings  7 ,  8 ,  9  to the outside is interrupted. A compression spring  16  which presses the valve part  10  into the closed position is provided between the valve part  10  and the converging guide part  3 . 
   The piston-like valve part  10  has an inwardly extending air inlet tube  11  which is guided centrally in the tubular section  6  at a distance thereto. In the embodiment shown for upside-down containers, a cup-like covering  12  which has a lower centering ring  13  is placed onto the inner end of the air inlet tube  11 . At the lower end of the air inlet tube  11  an annular sealing edge  20  can be formed, as  FIG. 5  shows. 
   The covering  12  contains a certain volume of air and prevents the flowable medium from being able to penetrate into the air inlet tube  11 . For air to pass from the inlet tube  11  into the covering  12 , holes  15  are provided in the upper end region. In the embodiment according to  FIGS. 1  to  4 , a further tube  14  is held in the interior of the inlet tube  11  via webs (not shown), said tube protruding slightly from the inlet tube  11  at the side of the valve part  10  and ending at a small distance from the covering  12 . The further tube  14  causes the air flowing in to be divided between two ducts, so that even if flowable medium penetrates into the air inlet tube  11 , ventilation can take place via the further tube  14 . 
   In the embodiment according to  FIGS. 5 and 6 , this further tube is absent, since the penetration of flowable medium through the annular gap between the tubular section  6  of the closure element  4  and the air inlet tube  11  is prevented by an approximately centrally arranged sealing ring  21 . 
   In the closed position according to  FIG. 1  or  5 , the covering  12  is seated in a sealing manner on the end of the tubular section  6  and the centering ring  13  is seated in a sealing manner on the guide part  3 . In order to open the valve and allow a first quantity of the flowable medium to flow out of the container  1  downward, the valve part  10  is raised to such an extent that the lowermost outflow opening  7  is opened up. Together with the lifting of the valve part  10 , the covering  12  is also lifted from its sealed seat at the end of the tubular section  6  and the guide part  3 , so that air can flow through the holes  15  into the covering  12  and through the lower centering ring  13  thereof into the interior of the container  1 . 
   If a relatively large quantity of flowable medium is to be removed from the container in the same unit of time, then the valve part  10  is lifted by a greater height (see  FIG. 3 ), so that the next higher outflow opening  8  is additionally opened up. The entire outflow cross section is correspondingly larger as a result.  FIGS. 4 and 6  shows a third open position, in which the valve part  10  is raised even higher, so that all of the uppermost outflow openings  9  are exposed. The flowable medium can therefore flow out downward through the tubular section  5  through all three openings  7 ,  8 ,  9  in a correspondingly large quantity per unit of time, with, in the embodiment according to  FIGS. 5 and 6 , an annular drip hood  19  being formed at the lower end of the tubular section  5 . The space  18  receiving the spring  16 , as  FIGS. 5 and 6  show, can be assigned a vent opening  17  in order to allow the air which is to be displaced during the raising of the valve part  10  to flow out.