Reciprocating pump

Abstract

A reciprocating pump includes a pump chamber; a suction port which enables a liquid to be suctioned into the pump chamber; a discharge port which enable a liquid in the pump chamber to be discharged; a plunger which is capable of reciprocating in the pump chamber by a motor; check valves are disposed between the pump chamber and a flow route on the suction port side and a flow route on the discharge port side, are openable and closable in response to a change in a liquid pressure in the pump chamber, which is produced due to the reciprocating of the plunger, a detection device that is able to detect a period of time during which the check valve is in an opened state or in a closed state in a predetermined cycle; and an arithmetic device that performs an arithmetic operation to obtain pump volumetric efficiency or a flow rate based on a comparison between a period of detection time detected by the detection device and a period of time during which the check valve is in the opened state or in the closed state in the predetermined cycle during normal operation.

1 . A reciprocating pump comprising:
 a pump chamber which is able to flow a liquid;   a suction port which enables a liquid to be suctioned into the pump chamber;   a discharge port which enable a liquid in the pump chamber to be discharged;   a reciprocating device which is capable of reciprocating in the pump chamber by a drive device and enables a liquid to be suctioned into the pump chamber from the suction port and enables the liquid to be discharged from the discharge port due to the reciprocating;   valve devices which are disposed between the pump chamber and a flow route on the suction port side and a flow route on the discharge port side, are openable and closable in response to a change in a liquid pressure in the pump chamber, which is produced depending on the reciprocating of the reciprocating device, allow a liquid to flow in an opened state, and block a liquid from flowing in a closed state;   a detection device that is able to detect a period of time during which the valve device is in the opened state or in the closed state in a predetermined cycle; and   an arithmetic device that performs an arithmetic operation to obtain pump volumetric efficiency or a flow rate based on a comparison between a period of detection time detected by the detection device and a period of time during which the valve device is in the opened state or in the closed state in the predetermined cycle during normal operation.   
     
     
         2 . The reciprocating pump according to  claim 1 ,
 wherein the detection device detects a period of time during which both the valve device on the suction port side and the valve device on the discharge port side are in the closed state in the predetermined cycle and the arithmetic device performs an arithmetic operation to obtain pump volumetric efficiency or a flow rate based on a comparison between the period of detection time detected by the detection device and a period of time during which both the valve device on the suction port side and the valve device on the discharge port side are in the closed state in the predetermined cycle during normal operation.   
     
     
         3 . The reciprocating pump according to  claim 1 ,
 wherein the detection device detects a period of time during which the valve device on the discharge side is in the opened state in the predetermined cycle and the arithmetic device performs an arithmetic operation to obtain pump volumetric efficiency or a flow rate based on a comparison between the period of detection time detected by the detection device and a period of time during which the valve device on the discharge side is in the opened state in the predetermined cycle during normal operation.   
     
     
         4 . The reciprocating pump according to  claim 1 ,
 wherein the liquid contains a conductive liquid and the detection device includes a transmitting electrode unit and a receiving electrode unit which are disposed on the pump chamber and on the flow route on the suction port side or on the flow route on the discharge port side, respectively, which are positioned to interpose the valve device therebetween and a calculating device that is able to calculate a detection period of time during which the valve device is in the opened state or in the closed state based on a period of current application time between the transmitting electrode unit and the receiving electrode unit.   
     
     
         5 . The reciprocating pump according to  claim 4 , further comprising:
 a shutout determination device that is able to determine whether or not the valve device is in a good shutout state and to monitor the shutout state based on the current application between the transmitting electrode unit and the receiving electrode unit.   
     
     
         6 . The reciprocating pump according to  claim 1 ,
 wherein the pump chamber is adapted to have a liquid supply-side pump chamber that communicates with a liquid supply-side suction port and a liquid supply-side discharge port and a liquid drainage-side pump chamber that communicates with a liquid drainage-side suction port and a liquid drainage-side discharge port, and has a configuration in which the valve device is provided for each of the liquid supply-side suction port, the liquid supply-side discharge port, the liquid drainage-side suction port, and the liquid drainage-side discharge port, the reciprocating device reciprocates in both the liquid supply-side pump chamber and the liquid drainage-side pump chamber, and thereby, liquids in the liquid supply-side pump chamber and the liquid drainage-side pump chamber are discharged from the liquid supply-side discharge port and the liquid drainage-side discharge port, respectively.   
     
     
         7 . The reciprocating pump according to  claim 6 ,
 wherein dialysate that is guided to a blood purification device flows in the liquid supply-side pump chamber, dialysate guided out from the blood purification device flows in the liquid drainage-side pump chamber, and the reciprocating of the reciprocating device enables dialysate to be supplied to the blood purification device and to be guided out from the blood purification device.   
     
     
         8 . The reciprocating pump according to  claim 6 ,
 wherein the arithmetic device obtains pump volumetric efficiency or a flow rate in the liquid supply-side pump chamber and in the liquid drainage-side pump chamber and is able to detect liquid leakage between the liquid supply-side discharge port and the liquid drainage-side suction port based on a comparison between pump volumetric efficiency or a flow rate in the liquid supply-side pump chamber and the pump volumetric efficiency or the flow rate in the liquid drainage-side pump chamber.   
     
     
         9 . The reciprocating pump according to  claim 2 ,
 wherein the liquid contains a conductive liquid and the detection device includes a transmitting electrode unit and a receiving electrode unit which are disposed on the pump chamber and on the flow route on the suction port side or on the flow route on the discharge port side, respectively, which are positioned to interpose the valve device therebetween and a calculating device that is able to calculate a detection period of time during which the valve device is in the opened state or in the closed state based on a period of current application time between the transmitting electrode unit and the receiving electrode unit.   
     
     
         10 . The reciprocating pump according to  claim 3 ,
 wherein the liquid contains a conductive liquid and the detection device includes a transmitting electrode unit and a receiving electrode unit which are disposed on the pump chamber and on the flow route on the suction port side or on the flow route on the discharge port side, respectively, which are positioned to interpose the valve device therebetween and a calculating device that is able to calculate a detection period of time during which the valve device is in the opened state or in the closed state based on a period of current application time between the transmitting electrode unit and the receiving electrode unit.   
     
     
         11 . The reciprocating pump according to  claim 2 ,
 wherein the pump chamber is adapted to have a liquid supply-side pump chamber that communicates with a liquid supply-side suction port and a liquid supply-side discharge port and a liquid drainage-side pump chamber that communicates with a liquid drainage-side suction port and a liquid drainage-side discharge port, and has a configuration in which the valve device is provided for each of the liquid supply-side suction port, the liquid supply-side discharge port, the liquid drainage-side suction port, and the liquid drainage-side discharge port, the reciprocating device reciprocates in both the liquid supply-side pump chamber and the liquid drainage-side pump chamber, and thereby, liquids in the liquid supply-side pump chamber and the liquid drainage-side pump chamber are discharged from the liquid supply-side discharge port and the liquid drainage-side discharge port, respectively.   
     
     
         12 . The reciprocating pump according to  claim 3 ,
 wherein the pump chamber is adapted to have a liquid supply-side pump chamber that communicates with a liquid supply-side suction port and a liquid supply-side discharge port and a liquid drainage-side pump chamber that communicates with a liquid drainage-side suction port and a liquid drainage-side discharge port, and has a configuration in which the valve device is provided for each of the liquid supply-side suction port, the liquid supply-side discharge port, the liquid drainage-side suction port, and the liquid drainage-side discharge port, the reciprocating device reciprocates in both the liquid supply-side pump chamber and the liquid drainage-side pump chamber, and thereby, liquids in the liquid supply-side pump chamber and the liquid drainage-side pump chamber are discharged from the liquid supply-side discharge port and the liquid drainage-side discharge port, respectively.   
     
     
         13 . The reciprocating pump according to  claim 4 ,
 wherein the pump chamber is adapted to have a liquid supply-side pump chamber that communicates with a liquid supply-side suction port and a liquid supply-side discharge port and a liquid drainage-side pump chamber that communicates with a liquid drainage-side suction port and a liquid drainage-side discharge port, and has a configuration in which the valve device is provided for each of the liquid supply-side suction port, the liquid supply-side discharge port, the liquid drainage-side suction port, and the liquid drainage-side discharge port, the reciprocating device reciprocates in both the liquid supply-side pump chamber and the liquid drainage-side pump chamber, and thereby, liquids in the liquid supply-side pump chamber and the liquid drainage-side pump chamber are discharged from the liquid supply-side discharge port and the liquid drainage-side discharge port, respectively.   
     
     
         14 . The reciprocating pump according to  claim 5 ,
 wherein the pump chamber is adapted to have a liquid supply-side pump chamber that communicates with a liquid supply-side suction port and a liquid supply-side discharge port and a liquid drainage-side pump chamber that communicates with a liquid drainage-side suction port and a liquid drainage-side discharge port, and has a configuration in which the valve device is provided for each of the liquid supply-side suction port, the liquid supply-side discharge port, the liquid drainage-side suction port, and the liquid drainage-side discharge port, the reciprocating device reciprocates in both the liquid supply-side pump chamber and the liquid drainage-side pump chamber, and thereby, liquids in the liquid supply-side pump chamber and the liquid drainage-side pump chamber are discharged from the liquid supply-side discharge port and the liquid drainage-side discharge port, respectively.   
     
     
         15 . The reciprocating pump according to  claim 9 ,
 wherein the pump chamber is adapted to have a liquid supply-side pump chamber that communicates with a liquid supply-side suction port and a liquid supply-side discharge port and a liquid drainage-side pump chamber that communicates with a liquid drainage-side suction port and a liquid drainage-side discharge port, and has a configuration in which the valve device is provided for each of the liquid supply-side suction port, the liquid supply-side discharge port, the liquid drainage-side suction port, and the liquid drainage-side discharge port, the reciprocating device reciprocates in both the liquid supply-side pump chamber and the liquid drainage-side pump chamber, and thereby, liquids in the liquid supply-side pump chamber and the liquid drainage-side pump chamber are discharged from the liquid supply-side discharge port and the liquid drainage-side discharge port, respectively.   
     
     
         16 . The reciprocating pump according to  claim 7 ,
 wherein the arithmetic device obtains pump volumetric efficiency or a flow rate in the liquid supply-side pump chamber and in the liquid drainage-side pump chamber and is able to detect liquid leakage between the liquid supply-side discharge port and the liquid drainage-side suction port based on a comparison between pump volumetric efficiency or a flow rate in the liquid supply-side pump chamber and the pump volumetric efficiency or the flow rate in the liquid drainage-side pump chamber.