Abstract:
In a device for reversing the flow of flowing media including two multi-way valves ( 21 ) which are fluidically interconnected and mounted on an adapter plate ( 32 ), the two valves are identical and are fluidically connected with one another by being pushed one into the other via rotationally symmetrical sealing members that seal in the radial direction.

Description:
TECHNICAL FIELD  
       [0001]    The present invention relates to a device for flow reversal of flowing media, and further relates to a valve combination. 
       BACKGROUND OF THE INVENTION 
       [0002]    According to the prior art, pumps such as diaphragm pumps are capable of suction of a medium in the input and delivery of the medium in the output. A reversal of the direction of the medium delivered is not possible in diaphragm pumps which have passive inlet and outlet valves. 
         [0003]    It is further known from the prior art that the direction of flow in a fluid line may be reversed by combining two  3 -way valves, where the valves are, as a rule, arranged side by side on connecting plates. The electrical connection is mainly effected by means of single strands which are united in a cable harness and then led to a connector plug. 
         [0004]    A disadvantage here is that systems of this type are susceptible to vibrations, which frequently results in the single strands becoming detached. This may lead to disturbing failures of the equipment. 
         [0005]    As an alternative, for reversing the flow of diaphragm pumps valves systems are used in which a single coil actuates an elastomer-sheathed control member, two valve seats being opened and two other valve seats being closed at a time. In this variant, the fluid space is sealed by axially clamped seals. 
         [0006]    It is disadvantageous here that leakages may appear in case of thermal stress or mechanical influences. 
       SUMMARY OF THE INVENTION 
       [0007]    The present invention is intended to counter the above-mentioned disadvantages. This is achieved by a device for reversing the flow of flowing media, consisting of two multi-way valves which are fluidically interconnected and mounted on an adapter plate, in which the two valves are identical and are matingly interengaged with one another. This can be achieved by pushing one into the other via rotationally symmetrical sealing members that seal in a radial direction. This is further achieved by a valve combination for reversing a direction of flow of a medium by means of fluidically interconnected multi-way valves, in which provision is made for identical valve modules which are joined together so as to be complementary and include complementary coupling members which fluidically interconnect the joined valve modules. 
         [0008]    Combining a pump, in particular a diaphragm pump, with a device or a valve combination according to the present invention allows the direction of delivery of a medium to be reversed while maintaining the direction of delivery of the pump unchanged, i.e. upon switch-over of a multi-way valve combination, the line hitherto used as the suction line is employed for delivery, and the line hitherto used as the pressure line is employed for suction. 
         [0009]    In a further application, the present invention may be used to reverse the flow direction in a fluid line. 
         [0010]    Two identical valves are linked fluidically and electrically in such a way that a very compact and sturdy assembly is produced and a cost-effecting manufacture is allowed owing to standardization. The seals are designed to be rotationally symmetrical and sealing in the radial direction, as a result of which reliable tightness is obtained even in the case of extreme thermal stresses. 
         [0011]    The two identical multi-way valves integrated in the present invention are of such a design that they can be connected with each other in a simple manner and the connecting points are reliably sealed. Again using rotationally symmetrical and radially sealing seals, the connected valves are placed onto a mounting plate in which the medium is passed on to the inlet and outlet ports and, for example, to a feed pump. Preferably, the two valves are electrically connected in series; the coil connections lead directly to a connector, eliminating the need for pigtails. 
         [0012]    The compact mechanical design and the elimination of single strands result in an extremely robust system that is highly insensitive to ambient vibrations. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]      FIG. 1  shows an arrangement of two identical multi-way valves; 
           [0014]      FIG. 2  shows a sectional view of the multi-way valves of  FIG. 1 ; 
           [0015]      FIG. 3  shows a multi-way valve combination including an adapter plate, illustrating the fluidic linkage; 
           [0016]      FIG. 4  shows a fluidic circuit diagram of the multi-way valve combination with a delivery device; 
           [0017]      FIG. 5  shows a fluidic circuit diagram of the multi-way valve combination without a delivery device; and 
           [0018]      FIG. 6  shows an electrical connection of the two coils of the multi-way valve combination. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0019]      FIG. 1  illustrates a multi-way valve combination made up of two identical valve elements, each containing a fluid housing  1 A,  1 B and a coil  2 A,  2 B. On its top side, the coil  2 A,  2 B has a cylindrical extension  3 A,  3 B for an O-ring  4  to be slipped on that seals the respective fluid housing  1 A,  1 B in the radial direction. The two valve elements may be pushed one into the other, as is apparent from  FIG. 2 . 
         [0020]    The multi-way valve combination  21  is illustrated in  FIG. 3 . It may simply be mounted on any desired adapter plate. 
         [0021]    The coil  2 A,  2 B mainly consists of the winding  5 , the upper valve seat  6 A,  6 B, the core  7 A,  7 B, the lower core spring  8 A,  8 B and the housing seal  9 A,  9 B. 
         [0022]    Two ducts  10 A,  10 B connect the upper valve seats  6 A,  6 B and the housing seats  11 A,  11 B with each other, respectively. Connected with the respective ducts  10 A,  10 B are connecting ports  12 ,  13 , which lead to associated connecting pieces  16 ,  19 , respectively, in the adapter plate  32 . In one exemplary embodiment, the two connecting pieces  16 ,  19  are connected with two ports  22 A,  22 B of the pump. 
         [0023]    Connected to valve chambers  40 A,  40 B are respective further connecting ports  14 ,  15 , which lead to connecting pieces  18 ,  17 , respectively, in the adapter plate  32 . O-rings  20  provide for a sealing in the radial direction. 
         [0024]    The adapter plate  32  has fluid ports  23 ,  24  incorporated therein. Provision may be made here for the two pump ports  22 A,  22 B. 
         [0025]    The circuitry of the valves is apparent from  FIG. 4 , when, as in one embodiment, a delivery device such as e.g. a pump is used. By switching over the two valves in the multi-way valve combination  21 , the flow direction in the two connecting pipes  23 ,  24  will change. 
         [0026]      FIG. 5  illustrates a further embodiment without a delivery device. 
         [0027]      FIG. 6  shows the electrical connection of the two coils  2 A,  2 B. Two connector lugs  28 A,  28 B are electrically connected to a clamping member  25 . Clamping members  26 A,  26 B are used to lead two further connector lugs  29 A,  29 B to a female connector  27 . This provides for a series connection of the two coils. 
         [0028]    The mode of functioning of the device according to the invention will now be described below. 
         [0029]    In a first embodiment the medium is applied to the inlet  14  of the multi-way valve combination  21  in a de-energized condition and flows through the valve chamber  40 A and via the open valve seat  6 A to the port  13 , which is connected to the suction-side input of a pump. The core  7 A made of a magnetic material, which has sealing bodies or seals  31 A,  30 A firmly connected to it, closes the valve seat  11 A by means of the spring  8 A, and therefore no medium reaches the duct  10 A. The duct  10 B contains a medium which is applied to the seal  31 B. The core  7 B, which has seals  31 B,  30 B firmly connected to it, closes the valve seat  11 B by means of the spring  8 B, so that no medium reaches the valve chamber  40 B. 
         [0030]    The pressure-side output of the pump is connected to the port  12 , from where the medium flows through the opened valve seat  6 B and the valve chamber  40 B into the outlet  15 . Accordingly, in the de-energized condition, medium flows from the inlet  14  through the pump to the outlet  15  through the multi-way valve combination  21 . 
         [0031]    When the two valves in the multi-way valve combination are switched over, i.e. a current is applied to the coils  2 A,  2 B, the two cores  7 A,  7 B made of a magnetic material are attracted and close the valve seats  6 A,  6 B by means of the seals  30 A,  30 B, which are firmly connected to the ends of the cores  7 A,  7 B. The two valve seats  11 A,  11 B are opened. The medium will now flow from the outlet  15  through the multi-way valve combination  21  and to the inlet  14 , with the delivery direction of the pump unchanged. 
         [0032]    The seals may be vulcanized onto the cores, for example. As an alternative, the seals may be resiliently mounted inside the cores.