Pump element for a tube pump

Abstract

The invention relates to a tube pump comprising a tube and a pump element inserted in the tube, where the pump element comprises a rod element and a first and a second non-return valve member positioned a distance apart on the rod element. The valve members are oriented in the same direction relative to the rod element so as to allow for a fluid flow in the tube through the first valve member, along the rod element, and through the second valve member. The tube comprises an at least partly flexible tube portion between the valve members such that a repeated deformation of the flexible tube portion acts to alternately close and open the valve members thereby generating a fluid flow through the tube. The invention further relates to a pump element comprising at least two non-return valve members connected by a rod element, and for insertion in an at least partly flexible tube in such tube pump as mentioned above, thereby acting to generate a fluid flow through the tube upon repeated deformation of the tube between the two valve members. The pump element may comprise a connecting part for coupling to another tube and may comprise a sealing part establishing a fluid tight connection to a part of the tube. The invention further relates to a method for creating a flow of a fluid within an at least partly flexible tube by means of a pump element as mentioned above.

1 . A tube pump comprising a tube and a pump element inserted in said tube, the pump element comprising a rod element and at least a first and a second non-return valve member positioned a distance apart on said rod element and oriented in a same direction relative to the rod element so as to allow for a fluid flow in the tube through the first valve member, along the rod element, and through the second valve member, and the tube comprising an at least partly flexible tube portion between said first and second valve members such that a repeated deformation of said flexible tube portion acts to alternately close and open the valve members thereby generating a fluid flow through the tube. 
     
     
         2 . The tube pump according to  claim 1 , where the pump element extends into the tube from one end of the tube, and where the pump element further comprises at least one sealing part engaging with the tube wall in a fluid tight fashion in one end of the tube. 
     
     
         3 . The tube pump according to  claim 1 , where the pump element extends through the entire length of the tube and comprises sealing parts engaging with the tube wall in a fluid tight fashion in both ends of the tube. 
     
     
         4 . The tube pump according to  claim 1 , where the tube is connected to a further tube via a connection part. 
     
     
         5 . The tube pump according to  claim 1  comprising at least one actuator of an electroactive polymer material arranged for deforming said flexible tube portion when actuated. 
     
     
         6 . The tube pump according to  claim 5 , where said electroactive polymer material is arranged on a wall portion of said flexible tube portion. 
     
     
         7 . The tube pump according to  claim 1  comprising at least one actuator comprising a movable contact plate arranged for deforming said flexible tube portion by compressing the tube when actuated. 
     
     
         8 . The tube pump according to  claim 1  comprising at least two pump elements placed serially. 
     
     
         9 . The tube pump according to  claim 1 , where at least one of the valve members comprises a flexible membrane fitted onto the rod element and sized to at least partly engage in its closed position with the inner wall of the tube. 
     
     
         10 . The tube pump according to  claim 1 , where the valve members comprise valves placed in valve housings at least partly engaging with the inner wall of the tube. 
     
     
         11 . The tube pump according to  claim 1 , where at least one of the valve members comprises a flexible funnel shaped membrane and a perforated disk fitted onto the rod element, the disk being sized to engage with the interior of the tube in a fluid tight fashion. 
     
     
         12 . The tube pump according to  claim 11 , where the membrane is sized to cover the disk perforations if pressed against the disk. 
     
     
         13 . The tube pump according to  claim 1 , further comprising a free flow prevention device mounted on said rod element between said first and second valve members, the free flow prevention device comprising a valve element which in the closed configuration of the device is sized to engage with the interior of the tube in a fluid tight fashion, and which is configured to be opened by said deformation of said flexible tube portion pressing on at least a part of said valve element. 
     
     
         14 . The tube pump according to  claim 13 , where the valve element of the free flow prevention device comprises a funnel-shaped membrane. 
     
     
         15 . The tube pump according to  claim 13 , where the valve element of the free flow prevention device comprises a foam member. 
     
     
         16 . A pump element for a tube pump according to  claim 1 , where the pump element is configured for insertion into a tube and to aid in generating a flow of a fluid within the tube, the pump element comprising said rod element with at least said first and second non-return valve members positioned a distance apart on said rod element and oriented in the same direction relative to the rod element so as to allow for a fluid flow through the first valve member, along the rod element, and through said second valve member, whereby the pump element when inserted in a flexible tube may act to generate a fluid flow through said tube upon repeated deformation of said tube between said first and second valve members. 
     
     
         17 . The pump element according to  claim 16 , where the pump element further comprises a sealing part positioned on one side of said first and second valve members and configured to establish a fluid tight connection to an end part of a tube when the pump element is inserted in said tube. 
     
     
         18 . The pump element according to  claim 16 , where the pump element further comprises a pipe connection part configured for connecting the pump element to a further tube. 
     
     
         19 . The pump element according to  claim 16 , where said first and second valve members comprise valves belonging to the group of ball valves, duckbill valves, diaphragm valves, wafer valves, check valves, swing check valves, disc check valves, split disc check valves, tilting disk check valves, cross slit valves, umbrella valves, and lift-check valves. 
     
     
         20 . The pump element according to  claim 16 , where the connecting rod is made of a bendable material such as a thermoplast. 
     
     
         21 . The pump element according to  claim 16 , where the connecting rod is made of PE (polyethylene), PP (polypropylene), a rubber, or a metal alloy. 
     
     
         22 . The infusion pump comprising a tube pump according to  claim 1 . 
     
     
         23 . A method for creating a flow of a fluid within an at least partly flexible tube, comprising the steps of
 connecting at least a first and a second non-return valve member to a connecting rod element a distance apart and such that said first and second valve members are oriented in a same direction relative to the rod element,   inserting said rod element with said valve members into said tube such that said valve members when closed at least partly engage with the tube wall,   repeatingly deforming at least a part of the tube between said first and second valve members thereby alternately closing and opening said valve members and thereby generating a fluid flow through the tube.   
     
     
         24 . The non-return valve member for use in a tube pump according to  claim 1 , where the valve member is configured for insertion into a tube and to aid in controlling a flow of a fluid within the tube, the valve member comprising a flexible funnel shaped membrane and a perforated disk sized to engage with the interior of the tube in a fluid tight fashion, the valve member further comprising a rod element onto which the disk and the membrane are mounted. 
     
     
         25 . The valve member according to  claim 24  where the funnel shaped membrane in the closed configuration of the valve member is placed such as to cover the disk perforations. 
     
     
         26 . The valve member according to  claim 24  where the membrane is mounted on the rod element by sticking the rod element through a hole in the membrane, the hole being of a smaller diameter than the diameter of the rod.