Patent Publication Number: US-2021170085-A1

Title: Blood purification device

Description:
TECHNICAL FIELD 
     The present invention relates to a configuration of a blood purification device. 
     BACKGROUND 
     To facilitate handling of blood purification devices, there is proposed a blood purification device including a body including a pump rotor and a controller, and a cassette housing a dialyzer, pump tubes, a blood loop, and other components and removably assembled to the body. This blood purification device is configured such that, when the cassette is assembled to the body, the pump tubes in the cassette are sequentially squeezed by the pump rotor in the body to pressure-feed blood and dialysate, for example, to the dialyzer (see Patent Document 1, for example). 
     During dialysis, water removal is performed to remove excessive water out of the patient&#39;s body. As the feed amounts of a blood pump and a dialysate pump need to be controlled based on the amount of removed water, it is necessary to store the removed water in a bag and measure the amount of removed water. To this end, the weight of the bag placed outside the blood purification device is measured to thereby determine the amount of removed water (see Patent Document 2, for example). 
     CITATION LIST 
     Patent Literature 
     [Patent Document 1] JP 2007-97746 A 
     [Patent Document 2] JP 5657726 B 
     SUMMARY 
     Technical Problem 
     While the conventional blood purification device disclosed in Patent Document 1 partially houses wet parts within the cassette, some wet parts such as a removed water container, for example, need to be separately attached to the blood purification device as described in Patent Document 2. Further simplification of handling of blood purification devices is therefore required. 
     The present invention is therefore aimed at simplification of handling of blood purification devices. 
     Solution to Problem 
     A blood purification device according to the present invention includes a device body, and a cassette to be removably assembled to the device body. The cassette includes a casing that houses a removed water container, and the cassette is attachable and removable with respect to the device body. 
     The removed water container mounted in the cassette can be thus integrally assembled to the device body removably, which simplifies handling of the blood purification device. 
     The blood purification device according to the present invention may further include a load detector mounted on the device body and configured to measure a load of the removed water container, and a load transmission mechanism configured to transmit to the load detector the load of the removed water container housed in the cassette. 
     This configuration enables measurement of the weight of the removed water container housed in the cassette by the device body housing the load detector, thereby simplifying handling of the blood purification device. 
     In the blood purification device according to the present invention, the load transmission mechanism may include a hole in a bottom board of the cassette in a portion where the removed water container is housed, and the removed water container may be configured to be placed on or above the load detector. The device body may include a base on which the load detector is mounted, and the load detector may be inserted through the hole. The device body may further include a cassette seat configured to receive the cassette. The load transmission mechanism may include the hole, and an opening in the cassette seat at a location corresponding to the hole in the cassette, and the load detector may be inserted through the hole and the opening. 
     This simple configuration enables measurement of the weight of the removed water container housed in the cassette by the device body that houses the load detector. 
     In the blood purification device according to the present invention, the device body may include a base on which the load detector is mounted. The load transmission mechanism may include the hole, and a spacer inserted through the hole. The spacer may be sandwiched between the load detector mounted on the base and a bottom face of the removed water container to thereby lift the removed water container up off a bottom board of the cassette. The removed water container may be configured to be placed on the spacer on top of the load detector. Further, the device body may include a cassette seat configured to receive the cassette and disposed with an interval from the base. The load transmission mechanism may further include an opening in the cassette seat at a location corresponding to the hole of the cassette, and the spacer may be inserted through the hole and the opening and sandwiched between the load detector mounted on the base and a bottom face of the removed water container to thereby lift the removed water container up off the bottom board of the cassette that is assembled to the device body to bring the bottom face of the cassette into contact with the cassette seat of the device body. 
     This simple configuration enables measurement of the weight of the removed water container housed in the cassette by the device body that houses the load detector. 
     In the blood purification device according to the present invention, the load transmission mechanism may include an opening in a top board of the cassette in a portion where the removed water container is housed, and an engaging unit protruding on an upper portion of the removed water container, and the removed water container may be suspended from the load detector. Further, the load transmission mechanism may include a connector coupled with the load detector mounted on the device body, which is configured to engage the engaging unit of the removed water container through the opening to lift the removed water container up off a bottom board of the cassette assembled to the device body, and the removed water container may be suspended from the load detector via the connector. 
     This simple configuration enables measurement of the weight of the removed water container housed in the cassette by the device body that houses the load detector. 
     In the blood purification device according to the present invention, the device body may include a heater disposed such that part or all of the heater enters the interior of the cassette that is assembled to the device body. For example, the heater may be disposed in a region under the removed water container housed in the cassette when the cassette is assembled to the device body, such that part or all of the heater enters the interior of the cassette from below. Further, the removed water container may include a recess portion in its bottom such that, when the cassette is assembled to the device body, the heater may enter the recess portion from below. Also, the heater may be inserted into the interior of the cassette from the side of the cassette or from above the cassette. 
     In the blood purification device according to the present invention, the device body may include a heater to be disposed near the cassette that is assembled to the device body. For example, the device body may include the heater to be located near a region under the cassette when the cassette is assembled to the device body. The device body may include the heater to be located adjacent to a side face of the cassette when the cassette is assembled to the device body. The device body may include the heater to be located near a region above the cassette when the cassette is assembled. 
     This simple configuration enables measurement of the weight of the removed water container housed in the cassette by the device body that houses the load detector and also enables heating of the dialysate to thereby maintain the temperature of blood to be reinfused to the patient. 
     In the blood purification device according to the present invention, the cassette may further house a dialyzer and a dialysate regeneration column. Further, the blood purification device according to the present invention may further include a pump unit including an elastic pump tube, a tube receiver configured to receive the pump tube, a tube pressing member configured to press a portion of the pump tube onto the tube receiver, and a driver unit configured to move the tube pressing member along a longitudinal direction of the pump tube, and configured to squeeze out liquid within the pump tube. In the blood purification device, the cassette may include at least a portion of the pump unit, and the device body may include a further portion of the pump unit. Here, the cassette may include the tube receiver and the pump tube of the pump unit, and the device body may include the tube pressing member and the driver unit. The tube receiver may be the casing of the cassette, and the pump tube may be mounted on an outer face of the casing. The tube pressing member may include a plurality of fingers, and the cassette may be attachable and removable with respect to the device body such that the pump tube is located between the fingers and the outer face of the casing. Further, here, the cassette may include the tube receiver, the pump tube, and the tube pressing member of the pump unit, and the device body may include the driver unit. The tube pressing member may be a rotor. The pump tube may include an arc portion along an outer circumference of the rotor. The tube receiver may be a stator including an arc portion along an outer circumference of the pump tube. The cassette may be attachable and removable with respect to the device body such that the rotor engages the driver unit when the cassette is assembled to the device body and the rotor is separated from the driver unit when the cassette is removed from the device body. 
     This configuration enables all of wet parts to be integrally assembled or removed with respect to the device body to thereby simplify handling of the blood purification device. 
     Advantageous Effects of Invention 
     The present invention simplifies handling of blood purification devices. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a perspective view of a blood purification device according to an embodiment. 
         FIG. 2  is an exploded perspective view of the blood purification device according to the embodiment. 
         FIG. 3  is a vertical cross section of the blood purification device according to the embodiment. 
         FIG. 4  is a horizontal cross section of the blood purification device according to the embodiment. 
         FIG. 5  is a cross section taken along line A-A shown in  FIG. 4 . 
         FIG. 6  is an explanatory view illustrating a load transmission mechanism of a blood purification device according to another embodiment. 
         FIG. 7  is an explanatory view illustrating a load transmission mechanism of a blood purification device according to another embodiment. 
         FIG. 8  is a cross section illustrating a load transmission mechanism in a modification example of the blood purification device illustrated in  FIG. 1 . 
         FIG. 9  is a cross section illustrating another modification example of the blood purification device illustrated in  FIG. 1 . 
         FIG. 10  is a cross section illustrating still another modification example of the blood purification device illustrated in  FIG. 1 . 
         FIG. 11  is a cross section illustrating still another modification example of the blood purification device illustrated in  FIG. 1 . 
         FIG. 12  is a horizontal cross section illustrating another modification example of the blood purification device illustrated in  FIG. 1 . 
         FIG. 13  is a horizontal cross section illustrating still another modification example of the blood purification device illustrated in  FIG. 1 . 
         FIG. 14  is a horizontal cross section illustrating still another modification example of the blood purification device illustrated in  FIG. 1 . 
         FIG. 15  is an exploded perspective view illustrating another modification example of the blood purification device illustrated in  FIG. 1 . 
         FIG. 16  is a cross section of another modification example of the blood purification device illustrated in  FIG. 15 . 
         FIG. 17  is a cross section of a modification example of the blood purification device illustrated in  FIG. 7 . 
         FIG. 18  is a cross section of another modification example of the blood purification device illustrated in  FIG. 7 . 
         FIG. 19  is a cross section of still another modification example of the blood purification device illustrated in  FIG. 7 . 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     A blood purification device  100  according to an embodiment will be described by reference to the drawings. As illustrated in  FIG. 1 , the blood purification device  100  includes a device body  10 , and a cassette  30  removably assembled to the device body  10 . The cassette  30  is assembled to the device body  10  with a lower part of the cassette  30  fitted in a cassette seat  13  of the device body  10  and a hook  35  in an upper part of the cassette  30  fastened with a fitting  18  of the device body  10 . For use in dialysis, for example, a blood inlet nozzle  51   a  and a blood outlet nozzle  51   b  of the cassette  30  are respectively coupled with blood vessels of a patient&#39;s body. In the following description, the direction in which the device body  10  and the cassette  30  are arranged is referred to as a front-rear direction, the direction orthogonal to the front-rear direction in a horizontal plane as a width direction, and the vertical direction as an up-down direction. 
     As illustrated in  FIG. 2 , the cassette  30  includes a casing  31  that houses a dialyzer  36 , a dialysate regeneration column  38 , and a removed water container  37 , and the casing  31  includes, on an outer face  32   a  of its rear board  32 , a plurality of elastic pump tubes  41  ( 41   a  to  41   c ). The casing  31  forms a tube receiver that receives the pump tubes  41 . As illustrated in  FIG. 3 , the device body  10  includes a finger casing  14  storing a plurality of fingers  15 , driver units  16  of the fingers  15 , a controller  20  that performs driving control of the driver units  16 , and a housing  11  that houses these elements. The fingers  15  are tube pressing members that compress the pump tubes  41  radially while moving the compressing position along the longitudinal direction of the pump tubes  41  to thereby allow the interior liquid to flow. The fingers  15  and the finger casings  14  form a peristaltic pump that is a pump unit. 
     The blood purification device  100  includes a blood loop and a dialysate loop. The blood loop is a liquid loop that returns blood of a human body flowing from the blood inlet nozzle  51   a  back to the human body through the blood outlet nozzle  51   b , and includes the pump tube  41   a  of the blood pump, a blood flow channel of the dialyzer  36 , a drip chamber, and a coupling tube that couples these elements together. The dialysate loop is a liquid loop that circulates the dialysate in the dialyzer  36 , and includes a dialysate fluid channel of the dialyzer  36 , the dialysate regeneration column  38 , the removed water container  37 , the pump tube  41   b  of a dialysate outlet pump, the pump tube  41   c  of a dialysate inlet pump, and a coupling tube that couples these elements. The dialysate regeneration column  38  may be disposed anywhere within the dialysate loop. 
     The blood purification device  100  allows blood to flow through the blood loop and allows dialysate to flow through the dialysate loop to remove unnecessary waste and excess water out of the blood by the dialyzer  36 . The blood loop and the dialysate loop form wet parts. As illustrated in  FIGS. 1 and 2 , the cassette  30  includes the dialyzer  36 , the dialysate regeneration column  38 , the removed water container  37 , a drip chamber, the pump tubes  41   a  to  41   c , the blood inlet nozzle  51   a , the blood outlet nozzle  51   b , and the coupling tubes coupling these elements. 
     While in the description, the pump tubes  41   a  to  41   c  correspond to the blood pump, the dialysate outlet pump, and the dialysate inlet pump, respectively, the pump tubes  41   a  to  41   c  may be included in any of the blood pump, the dialysate outlet pump, and the dialysate inlet pump. 
     As illustrated in  FIG. 2 , the housing  11  of the device body  10  includes a base  12  that is a rectangular board, right and left L-shape side boards  11   a , a front board  11   b  attached at the front of the base  12 , and the cassette seat  13 . As illustrated in  FIG. 3( a ) , the base  12  includes a rib  12   a  in its center, and the cassette seat  13  is mounted on the front portions of the right and left side boards  11   a , the front board  11   b , and the rib  12   a . As such, the cassette seat  13  is assembled to the base  12  with an interval between the cassette seat  13  and the base  12 . 
     As illustrated in  FIGS. 2 and 3 , the cassette seat  13  includes a flat receiving board  13   a  mounted on the front portion of the right and left side boards  11   a , the front board  11   b , and the rib  12   a  and receiving a bottom board  34  of the cassette  30 , and a vertical flange  13   b  raising on opposite widthwise ends and the front end of the receiving board  13   a . An inner face of the vertical flange  13   b  is sloped outward to facilitate receiving of the cassette  30 , as illustrated in  FIG. 5 . 
     The finger casings  14   a  to  14   c  forming the blood pump, the dialysate outlet pump, and the dialysate inlet pump, respectively, are mounted on an upper face of the base  12 . Each of driver units  16   a  to  16   c  is attached to the corresponding one of the finger casings  14   a  to  14   c.    
     As illustrated in  FIGS. 2 and 3 ( a ), the casing  31  of the cassette  30  includes the bottom board  34 , the rear board  32  raising vertically from a rear edge of the bottom board  34 , side boards  31   a  raising vertically from opposite widthwise edges of the bottom board  34 , and a front board  31   b  raising vertically from a front edge of the bottom board  34 . The dialyzer  36 , the dialysate regeneration column  38 , and the removed water container  37  are housed within a space enclosed by the bottom board  34 , the side boards  31   a , the front board  31   b , and the rear board  32 . The coupling tube coupling the dialyzer  36 , the dialysate regeneration column  38 , and the removed water container  37  is also housed within the cassette  30 . 
     The pump tubes  41   a  to  41   c  are attached on a flat outer face  32   a  of the rear board  32  adjacent to the device body. The pump tubes  41   a  to  41   c  are coupled to the blood loop and the dialysate loop at their opposite ends. The pump tubes  41   a  to  41   c  have faces adjacent to the rear board  32  that are disposed along the flat outer face  32   a  of the rear board  32 . 
     As illustrated in  FIG. 2 , each of the finger casings  14   a  to  14   c  includes, on a frontward face, a vertically extending slot into which the corresponding one of the pump tubes  41   a  to  41   c  is fit. On assembling the cassette  30  to the device body  10 , with the rear board  32  of the cassette  30  facing the device body  10  as illustrated in  FIG. 2 , the pump tubes  41   a  to  41   c  are located between the slots of the corresponding finger casings  14   a  to  14   c  and the flat outer face  32   a  of the rear board  32 , as illustrated in  FIG. 4 . Upon being driven by the corresponding driver units  16   a  to  16   c , respectively, the fingers  15   a  to  15   c  press the elastic pump tubes  41   a  to  41   c , respectively, as illustrated in  FIG. 3( b ) . 
       FIG. 5  is a cross section of a portion of the cassette  30  where the removed water container  37  is housed, taken along line A-A in  FIG. 4 . As illustrated in  FIG. 5 , the cassette  30  includes a hole  34   c  in a region of the bottom board  34  where the removed water container  37  is housed. Meanwhile, the cassette seat  13  also includes an opening  13   c  at a location corresponding to the hole  34   c  formed on the bottom board  34  of the cassette  30 . The hole  34   c  and the opening  13   c  together form a single through hole through which a spacer  22  is inserted. A load detector  21  that measures the load of the removed water container  37  is disposed on an upper face of the base  12  under the spacer  22 . The spacer  22  has such a thickness that allows the spacer  22  to protrude from an upper face  34   b  of the bottom board  34  to lift the bottom face  37   a  of the removed water container  37  up off the upper face  34   b  of the bottom board  34 , when the cassette  30  is assembled to the device body  10  to bring an undersurface  34   a  of the bottom board  34  into contact with an upper face  13   d  of the cassette seat  13 . 
     As indicated by a dashed and single-dotted line in  FIG. 5 , prior to assembling the cassette  30  to the device body  10 , the load of the removed water container  37  is supported by the upper face  34   b  of the bottom board  34  of the casing  31 . In assembling the cassette  30  to the housing  11  of the device body  10  to bring the undersurface  34   a  of the bottom board  34  closer to the upper face  13   d  of the cassette seat  13 , the upper face of the spacer  22  starts protruding through the upper face  34   b  of the bottom board  34 . Then, after the cassette  30  is assembled to the housing  11  of the device body  10  to bring the undersurface  34   a  of the bottom board  34  in contact with the upper face  13   d  of the cassette seat  13 , the upper face of the spacer  22  protrudes through the upper face  34   b  of the bottom board  34  to lift the bottom face  37   a  of the removed water container  37  up off the upper face  34   b  of the bottom board  34 , as indicated by a solid line in  FIG. 5 . The spacer  22  is sandwiched between the load detector  21  and the bottom face  37   a  of the removed water container  37  to transmit the load of the removed water container  37  to the load detector  21 . As described, the load detector  21  disposed on the device body  10  is capable of measuring the load of the removed water container  37  housed within the cassette  30  and placed above the load detector  21 . As such, the load detector  21  measures the load of the removed water container  37  containing liquid, not the weight of the whole cassette  30 , which allows accurate measurement of the load of the removed water container  37 . 
     The hole  34   c  formed in the bottom board  34  of the cassette  30 , the opening  13   c  formed in the cassette seat  13 , and the spacer  22  inserted through the hole  34   c  and the opening  13   c  form a load transmission mechanism that transmits the load of the removed water container  37  to the load detector  21 . 
     While in the above description, the load detector  21  and the spacer  22  are separate elements, other configurations may be employed. For example, the load detector  21  may be configured to be inserted through the hole  34   c  formed in the bottom board  34  of the cassette  30  and the opening  13   c  formed in the cassette seat  13  such that, when the cassette  30  is assembled to the housing  11  of the device body  10 , the upper face of the load detector  21  protrudes through the upper face  34   b  of the bottom board  34  to allow the removed water container  37  to be placed directly on the load detector  21 . 
     A configuration without the cassette seat  13  may also be employed. Specifically, the base  12  may have a recess in a region corresponding to the hole  34   c  formed in the bottom board  34  of the cassette  30  to allow the load detector  21  to be mounted in the recess and to be inserted through the hole  34   c  such that, when the cassette  30  is assembled to the housing  11  of the device body  10 , the upper face of the load detector  21  protrudes through the upper face  34   b  of the bottom board  34  and the removed water container  37  is placed on the load detector  21 . 
     The above configuration may be further modified such that the spacer  22  is superposed on the load detector  21 , and, when the cassette  30  is assembled to the housing  11  of the device body  10 , the upper face of the spacer  22  protrudes through the upper face  34   b  of the bottom board  34  to allow the removed water container  37  to be placed on the spacer  22 . 
     As described above, in the blood purification device  100  according to the embodiment, the cassette  30  collectively houses the dialyzer  36 , the removed water container  37 , the dialysate regeneration column  38 , and the pump tubes  41   a  to  41   c  and the coupling tubes that couple these elements, that form the blood loops and the dialysate loop, and the cassette  30  is removably assembled to the device body  10 . This configuration enables dialysis to be performed only by assembling the cassette  30  to the device body  10  and connecting the blood inlet nozzle  51   a  and the blood outlet nozzle  51   b  with a puncture needle inserted in the blood vessel of a patient&#39;s body, which simplifies handling of the blood purification device  100 . The cassette  30  that contains all of disposable components of the wet parts of the blood loop and the dialysate loop may be disposable, which allows disposal of these disposable components collectively. This also simplifies handling of the blood purification device  100 . 
     In the description of the blood purification device  100  according to this embodiment, the fingers  15  are the tube pressing elements of the pump unit, and the casing  31  is the tube receiver, and the pump is a peristaltic pump that presses the pump tubes  41  radially while shifting the pressing location along the longitudinal direction of the pump tube  41  to thereby squeeze out the liquid within the pump tubes  41 . However, the configuration of the blood purification device  100  is not limited to this example, and a squeezing roller pump may be employed. In this configuration, the tube pressing element of the pump unit is a rotor, and the pump tubes  41  having an arc portion along the outer periphery of the rotor are pressed by a stator serving as a tube receiver having an arc portion along the outer periphery of the pump tube  41 . In the configuration using a roller pump, the stator, the rotor, and the pump tubes are assembled to the cassette  30 , and the driver unit is attached to the device body  10 , and the cassette  30  may be attachable and detachable with respect to the device body  10  such that, when the cassette  30  is assembled to the device body  10 , the rotor engages the driver units and, when the cassette  30  is removed from the device body  10 , the rotor is detached from the driver units. 
     Further, in the configuration that employs a squeezing roller pump, the pump tube  41  including an arc portion along the outer periphery of the rotor and the stator including an arc portion along the outer periphery of the pump tube  41  are assembled to the casing  31  of the cassette  30 , and the rotor and the driver unit are attached to the device body  10 . The cassette  30  may be assembled to the device body  10  such that the pump tube  41  is disposed between the rotor and the stator. 
     The blood purification device  100  according to this embodiment further enables measurement of only the load of the removed water container  37  housed within the cassette  30  with the load detector  21  mounted on the device body  10 , not on the disposable cassette  30 , when the cassette  30  is assembled to the housing  11  of the device body  10 . This further simplifies handling of the blood purification device  100 . 
     While in the description of the blood purification device  100  according to this embodiment, the cassette  30  is assembled to the device body  10  with the fitting  18 , the cassette  30  may be assembled to the device body  10  with a fastening component or by rotating a lever, for example. Further, while in the above description, the cassette  30  includes the blood inlet nozzle  51   a  and the blood outlet nozzle  51   b , the blood purification device  100  is not limited to this configuration and may be configured such that part of the tubes of the blood loop directed to the patient&#39;s body extend out from the cassette  30 . 
     Referring to  FIGS. 6 and 7 , blood purification devices  200  and  300  according to further embodiments will be described. Further description of the elements similar to those of the blood purification device  100  described above by reference to  FIGS. 1 to 5  is omitted. 
     In a blood purification device  200  illustrated in  FIG. 6 , the cassette  30  has an opening  33   a , in a portion on a top board of a front cover  33  that houses the removed water container  37 ; the removed water container  37  includes, on the upper part, a handle  61  serving as a protruding engaging unit; and a hook  62  that is a connector is coupled with the load detector  21  mounted on the housing  11  of the device body  10 . When the cassette  30  is assembled to the housing  11  of the device body  10 , the hook  62  engages the handle  61  to allow the removed water container  37  to be suspended from the load detector  21 , such that the bottom face  37   a  of the removed water container  37  is lifted up off the upper face  34   b  of the bottom board  34  of the cassette  30 . This results in transmission of the load of the removed water container  37  to the load detector  21  mounted on the device body  10  to thereby enable measurement of the load of the removed water container  37  with the load detector  21 . 
     In the blood purification device  200  according to this embodiment, the opening  33   a  of the front cover  33 , the handle  61 , and the hook  62  form a load transmission mechanism that transmits the load of the removed water container  37  to the load detector  21 . 
     In a blood purification device  300  illustrated in  FIG. 7 , the handle  61  of the blood purification device  200  is modified into a protruding handle  63  that protrudes upward through the opening  33   a , and the hook  62  is modified as an arm  64 . When the cassette  30  is assembled to the housing  11  of the device body  10 , the arm  64  engages the protruding handle  63  that protrudes through the top board of the front cover  33  of the cassette  30  to thereby lift the removed water container  37  up off the upper face  34   b  of the bottom board  34  of the cassette  30 . The protruding handle  63  and the arm  64  then transmit the load of the removed water container  37  to the load detector  21  mounted on the device body  10  for measuring the load of the removed water container  37  with the load detector  21 . 
     In the blood purification device  300  according to this embodiment, the opening  33   a  of the front cover  33 , the protruding handle  63 , and the arm  64  form a load transmission mechanism that transmits the load of the removed water container  37  to the load detector  21 . 
     The blood purification devices  200  and  300  described above achieve advantages similar to the advantages of the blood purification device  100 . 
     Referring now to  FIG. 8 , a blood purification device  110  which is a modification example of the blood purification device  100  described above by reference to  FIGS. 1 to 5  will be described. The blood purification device  110  illustrated in  FIG. 8  includes a heater  71  in place of the spacer  22  of the blood purification device  100  described by reference to  FIGS. 1 to 5 , which is positioned in a region under the removed water container  37  housed in the cassette  30  when the cassette  30  is assembled to the device body  10 . The heater  71  is configured to be partially inserted, from below, into the cassette  30  when the cassette  30  is assembled to the device body  10 . The remaining configuration is the same as that of the blood purification device  100 . 
     As illustrated in  FIG. 8 , the heater  71  has such a thickness that allows the heater  71  to protrude from the upper face  34   b  of the bottom board  34  of the cassette  30 , when the cassette  30  is assembled to the device body  10  to make the undersurface  34   a  of the bottom board  34  in contact with the upper face  13   d  of the cassette seat  13 , to thereby lift the bottom face  37   a  of the removed water container  37  up off the upper face  34   b  of the bottom board  34 . 
     When the cassette  30  is assembled to the housing  11  of the device body  10  to bring the undersurface  34   a  of the bottom board  34  into contact with the upper face  13   d  of the cassette seat  13 , the upper face of the heater  71  protrudes from the upper face  34   b  of the bottom board  34  to lift the bottom face  37   a  of the removed water container  37  up off the upper face  34   b  of the bottom board  34 . The heater  71  is thus sandwiched between the load detector  21  and the bottom face  37   a  of the removed water container  37  to thereby transmit the load of the removed water container  37  to the load detector  21 . The removed water container  37  is thus placed above the load detector  21  to allow the load detector  21  mounted on the device body  10  to measure the load of the removed water container  37  housed in the cassette  30 . 
     The heater  71  comes into contact with the bottom face  37   a  of the removed water container  37  to heat the liquid stored in the removed water container  37 , and may be a sheet or plate shaped heater plate, for example. The heater  71  may also be an electromagnetic heater that heats a metal plate attached to the bottom face  37   a  of the removed water container  37  with high frequency electromagnetic force or a high-frequency induction heater. Heating the liquid stored in the removed water container  37  with the heater  71  enables heating of the dialysate to maintain the temperature of the blood reinfused to the patient. 
     Referring now to  FIG. 9 , a blood purification device  120  which is another modification example of the blood purification device  100  will be described. The blood purification device  120  illustrated in  FIG. 9  includes a heater  72  having a thin sheet or plate shape on the spacer  22  positioned in a region under the removed water container  37  of the blood purification device  100  described by reference to  FIGS. 1 to 5 . The heater  72  is configured to be entirely housed within the cassette  30  when the cassette  30  is assembled to the device body  10 . The remaining configuration is the same as that of the blood purification device  100 . 
     As illustrated in  FIG. 9 , the spacer  22  has such a thickness that allows the spacer  22  to protrude from the upper face  34   b  of the bottom board  34  of the cassette  30 , when the cassette  30  is assembled to the device body  10  to bring the bottom face  34   a  of the bottom board  34  into contact with the upper face  13   d  of the cassette seat  13 . The heater  72  disposed on the spacer  22  may be a heater plate having a thin sheet or plate shape, or may include a Peltier element, for example. 
     When the cassette  30  is assembled to the housing  11  of the device body  10  to bring the undersurface  34   a  of the bottom board  34  into contact with the upper face  13   d  of the cassette seat  13 , the heater  72 , along with the spacer  22 , is sandwiched between the load detector  21  and the bottom face  37   a  of the removed water container  37  to thereby transmit the load of the removed water container  37  to the load detector  21 . In this manner, the load detector  21  mounted on the device body  10  may measure the load of the removed water container  37  housed in the cassette  30 . Further, similar to the blood purification device  110  described above, heating the liquid stored in the removed water container  37  with the heater  72  enables heating of the dialysate to maintain the temperature of the blood to be reinfused to the patient. 
     The heater  72  may have any thickness that allows the total thickness of the spacer  22  and the heater  72  to protrude from the upper face  34   b  of the bottom board  34  when the undersurface  34   a  of the bottom board  34  of the cassette  30  is in contact with the upper face  13   d  of the cassette seat  13 , and may be greater than that illustrated in  FIG. 9  such that the heater  72  enters the hole  34   c . In this configuration, the heater  72  partially enters the cassette  30  when the cassette  30  is assembled to the device body  10 . 
     Referring now to  FIG. 10 , a blood purification device  130  will be described. The blood purification device  130  illustrated in  FIG. 10  includes the spacer  22  of the blood purification device  100  described above by reference to  FIGS. 1 to 5  but having an annular shape, and a heater  73  disposed inside the spacer  22 . The heater  73  is positioned in a region under the removed water container  37  housed in the cassette  30  that is assembled to the device body  10 . An upper part of the heater  73  enters the cassette  30  through the hole  34   c  when the cassette  30  is assembled to the device body  10 . The heater  73  may have a height that is level with the upper face of the spacer  22  to thereby receive the load of the removed water container  37  and transmit the load to the load detector  21 , or a height that is lower than the upper face of the spacer  22  to thereby prevent receiving of the load of the removed water container  37 . The heater  73  need not pass through the hole  34   c ; in this configuration, the heater  73  does not enter the cassette  30 , and is positioned near a region under the cassette  30 . The remaining configuration is the same as that of the blood purification device  100 . 
     The annular spacer  22 , similar to the spacer  22  of the blood purification device  100  described above, is sandwiched between the removed water container  37  and the load detector  21  to transmit the load of the removed water container  37  to the load detector  21 . Heating the liquid stored in the removed water container  37  with the heater  73  enables heating of the dialysate to maintain the temperature of the blood reinfused to the patient. 
     Referring now to  FIG. 11 , a blood purification device  140 , which is another modification example of the blood purification device  100 , will be described. As illustrated in  FIG. 11 , the blood purification device  140  includes a heater  74 , independently of the spacer  22  and load detector  21 , on the base  12  under the opening  13   c  formed in the cassette seat  13 . The heater  74  is positioned under the bottom face  37   a  of the removed water container  37  when the cassette  30  is assembled to the device body  10 . While an upper part of the heater  74  enters, through the hole  34   c , the cassette  30  when the cassette  30  is assembled to the device body  10 , the heater  74  is configured to have a height that is lower than the upper face of the spacer  22 , in order to prevent receiving of the load of the removed water container  37 . The heater  74  need not pass through the hole  34   c ; in this configuration, the heater  74  does not enter the cassette  30 , and is positioned near a region under the cassette  30 . The heater  74  may be an electromagnetic heater or a high frequency induction heater, for example. The heater  74  may include a heater plate having a sheet or plate shape, or a Peltier element, for example, and may be mounted on the base  12  under the opening  13   c . The heater  74  may be disposed in any region under the removed water container  37  housed in the cassette  30  assembled to the device body  10 , and may be mounted on the base  12  under the receiving plate  13   a  of the cassette seat  13  in the periphery of the opening  13   c , rather than in the region under the opening  13   c.    
     The blood purification device  140 , similar to the blood purification device  110 , heats the liquid stored in the removed water container  37  with the heater  74  to thereby heat the dialysate and maintain the temperature of the blood reinfused to the patient. 
     Referring now to  FIG. 12 , a blood purification device  150  that is another example of the blood purification device  100  described above will be described. The blood purification device  150  illustrated in  FIG. 12  includes a heater  75  positioned near a side face of the cassette  30  when the cassette  30  of the device body  10  is assembled to the device body  10 . The remaining configuration is the same as that of the blood purification device  100 . 
     As illustrated in  FIG. 12 , the blood purification device  150  includes the finger casings  14   a  to  14   c  in a region toward the dialysate regeneration column  38  to thereby form a space between the finger casing  14   a  and the side board  11   a  of the housing  11  of the device body  10 , and includes the heater  75  in this space. When the cassette  30  is assembled to the device body  10 , the heater  75  is positioned opposite the removed water container  37  housed in the cassette  30  in the front-rear direction, with the rear board  32  of the cassette  30  being interposed between the heater  75  and the removed water container  37 . 
     The heater  75  is a non-contact heater, which heats the removed water container  37  or the liquid stored in the removed water container  37  in a non-contact manner via the rear board  32  of the cassette  30 . The heater  75  may be, for example, an electromagnetic heater, or an optical heater that illuminates the removed water container  37  with light through a slit formed in the rear board  32  to thereby heat the removed water container  37 . The blood purification device  150 , similar to the blood purification devices  110 ,  120 , and  130 , heats the liquid stored in the removed water container  37  with the heater  75  to thereby heat the dialysate and maintain the temperature of the blood reinfused to the patient. 
     A blood purification device  160  illustrated in  FIG. 13 , contrary to the blood purification device  150  described above by reference to  FIG. 12 , includes the heater  75  that is located opposite the dialysate regeneration column  38  housed in the cassette  30  in the front-rear direction, via the rear board  32  of the cassette  30 , when the cassette  30  is assembled to the device body  10 . The remaining configuration is the same as that of the blood purification device  150  described above by reference to  FIG. 12 . 
     The blood purification device  160  heats the liquid stored in the dialysate regeneration column  38  with the heater  75  to thereby heat the dialysate and maintain the temperature of the blood reinfused to the patient. 
     A blood purification device  170  illustrated in  FIG. 14  includes an opening  32   b  in the casing  31  of the cassette  30  of the blood purification device  150  described by reference to  FIG. 12  on the rear board  32  located adjacent to the device body  10  and includes a warm air generator  76  in the device body  10  opposite ??the removed water container  37 ?? via the opening  32   b  in the front-rear direction. 
     The blood purification device  170  enables flowing of warm air from the warm air generator  76  through the opening  32   b  into the casing  31  of the cassette  30  to warm the dialyzer  36 , the removed water container  37 , and the dialysate regeneration column  38  housed in the cassette  30 , thereby heating the dialysate and maintaining the temperature of the blood reinfused to the patient. 
     A blood purification device  180  illustrated in  FIG. 15  includes the removed water container  37  having, on the bottom, a recess portion  37   b  which is configured to receive a heater  74   a  when the cassette  30  is assembled to the device body  10 . 
     In the blood purification device  180 , the heater  74   a  has a greater height than the heater  74  of the blood purification device  140  described by reference to  FIG. 11 , and the removed water container  37  includes the recess portion  37   b  on the bottom. When the cassette  30  is assembled to the receiving plate  13   a  of the cassette seat  13  of the device body  10 , the heater  74   a  enters the interior of the cassette  30  and also enters the recess portion  37   b  from under the removed water container  37  housed in the cassette  30 , as illustrated in  FIG. 16 . The bottom face  37   a  of the removed water container  37  abuts against the upper face of the spacer  22 , such that the load of the removed water container  37  is detected by the load detector  21 . Here, the heater  74   a  has a height which does not contact the upper part of the recess portion  37   b , to thereby avoid transmission of the load of the removed water container  37 . 
     The blood purification device  180  heats the removed water container  37  more efficiently with the heater  74   a  inserted in the recess portion  37   b  of the removed water container  37 . While in the embodiment described above, the heater  74   a  enters the interior of the cassette  30  from under the cassette  30 , other configurations may also be employed. In one example, the cassette  30  has an opening on the rear board  32  and the heater  74   a  is disposed on a partition board  11   c  of the device body  10 , such that, in assembling the cassette  30  to the device body  10 , the heater  74   a  may be inserted laterally from the back of the cassette  30 . In another example, the heater  74   a  is disposed in the upper part of the device body  10  while the cassette  30  has an opening on the top board, such that in assembling the cassette  30  to the device body  10 , the heater  74   a  may be inserted into the cassette  30  from above the cassette  30 . 
     A blood purification device  310  illustrated in  FIG. 17  includes a heater  77  protruding at a location above the cassette  30  from the partition board  11   c  of the housing  11  of the device body  10  adjacent to the cassette  30 , in a configuration including the removed water container  37  that is suspended from the arm  64  of the load detector  21  when the cassette  30  is assembled to the device body  10 , as in the blood purification device  300  described above by reference to  FIG. 7 . The heater  77  is disposed to be located near a region above the cassette  30 , when the cassette  30  is assembled to the device body  10 . 
     A blood purification device  320  illustrated in  FIG. 18  includes a heater  78  disposed on the undersurface of the receiving board  13   a  of the cassette seat  13  such that the heater  78  is located in a region under the cassette  30  when the cassette  30  is assembled to the device body  10 . 
     A blood purification device  330  illustrated in  FIG. 19  includes a heater  79  in the housing  11  of the device body  10  on the partition board  11   c  adjacent to the cassette  30 . The heater  79  is disposed to be located near the side face of the cassette  30  when the cassette  30  is assembled to the device body  10 . 
     The blood purification devices  310 ,  320 , and  330  described by reference to  FIG. 17  to  FIG. 18  heat the dialyzer  36 , the removed water container  37 , and the dialysate regeneration column  38  housed in the cassette  30  with the heaters  77 ,  78 , and  79 , to thereby enable heating of the dialysate and maintaining of the blood reinfused in the patient. 
     The present invention is not limited to the embodiments described above and includes all of modifications and corrections that do not depart from the technical range or gist of the invention as defined in the claims. 
     REFERENCE SIGNS LIST 
       10  device body,  11  housing,  11   a  side board,  11   b  front board,  11   c  partition board,  12  base,  12   a  rib,  13  cassette seat,  13   a  receiving board,  13   b  vertical flange,  13   c ,  33   a  opening,  13   d ,  34   b  upper face,  14 ,  14   a  to  14   c  finger casing,  15 , 15   a  to  15   c  finger,  16 ,  16   a  to  16   c  driver unit,  18  fitting,  20  controller,  21  load detector,  22  spacer,  30  cassette,  31  casing,  31   a  side board,  31   b  front board,  32  rear board,  32   a  outer face,  32   b  opening,  34  bottom board,  34   a  undersurface,  34   c  hole,  35  hook,  36  dialyzer,  37  removed water container,  37   a  bottom face,  38  dialysate regeneration column,  41 ,  41   a  to  41   c  pump tube,  51   a  blood inlet nozzle,  51   b  blood outlet nozzle,  61  handle,  62  hook,  63  protrusion handle,  64  arm,  71  to  74 ,  74   a ,  75 ,  77  to  79  heater,  76  warm air generator,  100 ,  110 ,  120 ,  130 ,  140 ,  150 ,  160 ,  180 ,  200 ,  300 ,  310 ,  320 ,  330  blood purification device.