Balancing Method and Balancing Unit Being Independent of Temperature Disturbance

Abstract

This disclosure relates to a method for determining a fluid balance between a first volume flow in a first section of a fluid circuit and a second volume flow of a second section of the fluid circuit. The method may also include adjusting, assuming or detecting a first temperature in the first section of the fluid circuit and a second temperature in the second section of the fluid circuit, or detecting a temperature difference between the first and the second sections. The method may also include detecting a second volume flow in a second section of the fluid circuit and forming a balance from at least the first volume flow and a corrected value of the second volume flow. The corrected value is determined from the detected second volume flow and the second temperature and/or the temperature difference.

What is claimed is: 
     
         1 . A method for determining a fluid balance between fluid flows in a fluid circuit of a medical functional device that does not comprise a balancing chamber, the method comprising:
 measuring, using a first magnetic-inductive flow sensor positioned within a first section of the fluid circuit, a first fluid volume flow in the first section of the fluid circuit towards a filter device, wherein the first section is directly coupled to the filter device;   measuring, within the first section, a first fluid temperature of fluid flowing through the first section of the fluid circuit towards the filter device;   measuring, using a second magnetic-inductive flow sensor positioned within a second section of the fluid circuit downstream of the filter device, a second fluid volume flow in the second section of the fluid circuit away from the filter device;   determining, within the second section, a second fluid temperature of fluid flowing through the second section of the fluid circuit and away from the filter device,   determining a temperature difference between the first fluid temperature and the second fluid temperature;   determining a corrected value of the second fluid volume flow based on the second fluid volume flow determined using the second magnetic-inductive flow sensor and (i) the determined second fluid temperature or (ii) the determined temperature difference; and   determining the fluid balance based on the first fluid volume flow and the corrected value of the second fluid volume flow.   
     
     
         2 . The method of  claim 1 , comprising:
 controlling or regulating at least one of the first fluid volume flow or the second fluid volume flow based on at least one of the fluid balance, the corrected value of the second fluid volume flow, the second fluid temperature, or the temperature difference.   
     
     
         3 . The method of  claim 1 , wherein the corrected value of the second fluid volume flow is based on a stored, temperature-dependent, physical quantity of the fluid in the fluid circuit, or a predetermined factor K, or both. 
     
     
         4 . A balancing unit configured to determine a fluid balance between a first fluid volume flow in a first section of a fluid circuit of a functional device and a second fluid volume flow in a second section of the fluid circuit of the functional device, the balancing unit comprising:
 a first temperature sensor arranged in the first section; and   a second temperature sensor arranged in the second section;   wherein:
 the functional device comprises the fluid circuit; 
 the functional device does not comprise a balancing chamber; and 
 the balancing unit comprises, or is in data communication with a controller configured to execute a method comprising:
 measuring, using a first magnetic-inductive flow sensor positioned within the first section of the fluid circuit, the first fluid volume flow in the first section of the fluid circuit towards a filter device, wherein the first section is directly coupled to the filter device; 
 measuring, within the first section, a first fluid temperature of fluid flowing through the first section of the fluid circuit towards the filter device; 
 measuring, using a second magnetic-inductive flow sensor positioned within the second section of the fluid circuit downstream of the filter device, the second fluid volume flow in the second section of the fluid circuit away from the filter device; 
 determining, within the second section, a second fluid temperature of fluid flowing through the second section of the fluid circuit and away from the filter device; 
 determining a temperature difference between the first fluid temperature and the second fluid temperature; 
 determining a corrected value of the second fluid volume flow based on the second fluid volume flow determined using the second magnetic-inductive flow sensor and (i) the determined second fluid temperature or (ii) the determined temperature difference; and 
 determining the fluid balance based on the first fluid volume flow and the corrected value of the second fluid volume flow. 
 
   
     
     
         5 . The balancing unit of  claim 4 , wherein the method further comprises:
 controlling or regulating at least one of the first fluid volume flow or the second fluid volume flow based on at least one of the fluid balance, the corrected value of the second fluid volume flow, the second fluid temperature, or the temperature difference.   
     
     
         6 . The balancing unit of  claim 4 , wherein the controller is in data communication with at least one of the first temperature sensor, the second temperature sensor, or at least one volume flow sensor of the functional device. 
     
     
         7 . The balancing unit of  claim 4 , wherein the functional device or the balancing unit is configured as a disposable. 
     
     
         8 . The balancing unit of  claim 4 , wherein the controller is configured to control a fluid volume flow of the fluid circuit. 
     
     
         9 . A medical treatment apparatus, comprising:
 a balancing unit configured to determine a fluid balance between a first fluid volume flow in a first section of a fluid circuit and a second fluid volume flow in a second section of the fluid circuit, the balancing unit comprising:   a functional device comprising the fluid circuit;   a first temperature sensor arranged in the first section and;   a second temperature sensor arranged in the second section;   
       wherein:
 the functional device does not comprise a balancing chamber; and 
 the balancing unit comprises or is in data connection with a controller configured to execute a method comprising:
 measuring, using a first magnetic-inductive flow sensor positioned within the first section of the fluid circuit, the first fluid volume flow in the first section of the fluid circuit towards a filter device, wherein the first section is directly coupled to the filter device; 
 measuring, within the first section, a first fluid temperature of fluid flowing through the first section of the fluid circuit towards the filter device; 
 measuring, using a second magnetic-inductive flow sensor positioned within the second section of the fluid circuit downstream of the filter device, the second fluid volume flow in the second section of the fluid circuit away from the filter device; 
 determining, within the second section, a second fluid temperature of fluid flowing through the second section of the fluid circuit and away from the filter device, 
 determining a temperature difference between the first fluid temperature and the second fluid temperature; 
 determining a corrected value of the second fluid volume flow based on the second fluid volume flow determined using the second magnetic-inductive flow sensor and (i) the determined second fluid temperature or (ii) the determined temperature difference; and 
 determining the fluid balance based on the first fluid volume flow and the corrected value of the second fluid volume flow. 
 
 
     
     
         10 . The medical treatment apparatus of  claim 9 , wherein the method further comprises controlling or regulating at least one of the first fluid volume flow or the second fluid volume flow based on at least one of the fluid balance, the corrected value of the second fluid volume flow, the second fluid temperature, or the temperature difference. 
     
     
         11 . The medical treatment apparatus of  claim 9 , wherein the controller is configured to control a fluid volume flow of the fluid circuit. 
     
     
         12 . A digital storage medium with electrically readable control signals that when executed by one or more processors causes one or more devices to carry out operations comprising:
 measuring, using a first magnetic-inductive flow sensor positioned within a first section of a fluid circuit, a first fluid volume flow in the first section of the fluid circuit towards a filter device, wherein the first section is directly coupled to the filter device;   measuring, within the first section, a first fluid temperature of fluid flowing through the first section of the fluid circuit towards the filter device;   measuring, using a second magnetic-inductive flow sensor positioned within a second section of the fluid circuit downstream of the filter device, a second fluid volume flow in the second section of the fluid circuit away from the filter device;   determining, within the second section, a second fluid temperature of fluid flowing through the second section of the fluid circuit and away from the filter device,   determining a temperature difference between the first fluid temperature and the second fluid temperature;   determining a corrected value of the second fluid volume flow based on the second fluid volume flow determined using the second magnetic-inductive flow sensor and (i) the determined second fluid temperature or (ii) the determined temperature difference; and   determining a fluid balance based on the first fluid volume flow and the corrected value of the second fluid volume flow.