Abstract:
A liquid mixing infusor includes a main body defining an internal chamber and has an upstream port, a downstream port and a confluent port. Each port is fluidly couplable with the internal chamber. A valve may be mounted within the internal chamber of the main body and is adapted for rotational movement between a blocking position interrupting fluid flow between the confluent port and one of the upstream port and the downstream port and between the upstream port and the downstream port, and a flow position permitting fluid flow between the upstream port and the downstream port. A manually manipulative member is mounted relative to the main body and operatively connected to the valve. The manipulative member is movable to cause corresponding movement of the valve between the blocking position and the flow position.

Description:
BACKGROUND 
       [0001]    1. Technical Field 
         [0002]    This disclosure pertains to a liquid-mixing infusor used in the medical field, connected to a plurality of infusion tubes, and equipped with a plurality of branch tubes and capable of switching the connection or blocking section of respective branch tubes. 
         [0003]    2. Description of Art 
         [0004]    The provision of normal saline solution, drug solution, into the body of a patient has been carried out previously by using infusion tubes. To prevent air from being mixed inside such infusion tubes and entering the body together with normal saline solution or drug solution, an air trap is installed in an infusion tube, and any air is trapped in this air trap, shown for example in Japanese Kokai Utility Model Application No. Sho 48[1973]-68994 (JP 48068994U). 
         [0005]    In the case of this air trap, a portion of the horizontal area of a flow path extending in the horizontal direction is interrupted, a trap space is installed above this interruption, one end of the flow path from one direction is bent upwards and connected to one end of the trap space. One end of the flow path extending in the other direction is bent upwards and connected to the other end of the trap space. Namely, it is configured to have an inverted U-shaped portion equipped with a trap space formed in the flow path, to allow any air to be trapped in the trap space and prevent any air from entering the body. 
       SUMMARY 
       [0006]    The air trap described above is used for an infusion tube for administering one kind of normal saline solution or drug solution, and no administration of multiple normal saline, drug solutions, is possible. Therefore, a liquid-mixing infusor to administer a plurality of normal saline or drug solutions by connecting or blocking a plurality of infusion tubes, but, in such a liquid-mixing infusor, it is difficult to prepare a structure preventing air from entering the body. 
         [0007]    This disclosure has been created for circumstances as described above to provide a liquid-mixing infusor making it possible to remove any air in liquids and to connect or block any optional branch tubes among a plurality of branch tubes. 
         [0008]    To accomplish the above objective, the liquid-mixing infusor of this disclosure is characterized with respect to the configuration by being equipped with a liquid mixing infusor main body including a chamber, the central portion of which is formed in a cylindrical shape with its axial direction set vertically, a branching portion formed above the chamber and equipped with a connectable or interruptible flow path to the inside of the chamber, and pair of branch tubes extending outwards from both sides of the peripheral surface of the center portion of the chamber and respectively having flow paths connected to the inside of the chamber; a valve installed inside the chamber in a rotatable state in the periaxial direction of the chamber and blocking between the pair of branch tubes and the chamber or connecting at least one of the pair of branch tubes and inside of the chamber through the branching portion; and a rotary portion extending outside of the chamber from the valve and having an operation portion rotatable in the periaxial direction of the chamber on the outside of the chamber. 
         [0009]    The liquid-mixing infusor of this disclosure configured as described above has a rotation portion including a valve rotatable in the periaxial direction of the chamber and an operation portion extending out of the chamber from the valve and rotatable on the outer side of the chamber. Moreover, it is configured so that the valve can connect or block between the pair of branch tubes and the inside of the chamber by rotating the operation portion. Namely, this valve allows blocking between the pair of branch tubes and chamber or connection of tubes and chamber, and moreover, it allows one of the pair of branch tubes and the inside of the chamber to be connected. 
         [0010]    Furthermore, by connecting the flow path of the branching portion to the chamber, it is possible to connect the flow path of the branching portion to one or both of the pair of branch tubes. As a result, it is possible to supply one or two kinds of drug solutions to the patient&#39;s body. In addition, if a drug solution is allowed to flow in a flow path formed by connecting between the pair of branch tubes and inside the chamber, the drug solution passes the branching portion formed above the chamber. 
         [0011]    Specifically, the branching portion has a space formed above the flow path connecting one branch tube to the other branch tube through the chamber. As a result, if a drug solution is allowed to pass through a flow path connected through the branching portion, the drug solution flows so as to push any air inside the branching portion to the downstream side of the flow path. Therefore, before supplying the drug solution to the inside of the patient&#39;s body, the air inside the flow path can be discharged together with a small amount of the drug solution, and the flow path can be filled with the drug solution without any air. Consequently, air is prevented from entering the body when the drug solution is administered to the body. Similarly, when the flow path of the branching portion is connected to the chamber, any air inside the branching portion and chamber can be expelled from the flow path of the branching portion with the drug solution being supplied, and subsequently, the drug solution can be supplied to the body. 
         [0012]    Another characteristic of the liquid-mixing infusor of this disclosure with respect to its configuration is that the chamber may be formed as a based cylinder open at the top and closed at the bottom, the operation portion being formed as a cap-shaped body attached rotatably on the top end opening side of the chamber and a branching portion being installed inside the operation portion. 
         [0013]    Accordingly, the bottom of the chamber can be formed as a flat surface; consequently, for example, it is possible to install a plurality of liquid-mixing infusors on an installation plate, and each liquid-mixing infusor may have a plurality of infusion tubes connected. With this set up, it is possible to feed a large number of drug solutions to the body concomitantly. In addition, by installing the liquid-mixing infusor on an installation plate, the operation of the operation portion can be carried out easily with a single hand. Moreover, the operation part is positioned at the top of each liquid-mixing infusor; consequently, it is easy to see, and the operation position of the rotary portion can be easily confirmed. Furthermore, the cap-shaped body may be installed directly on the top end opening of the chamber, or it may be installed on the top end opening through a part such as valve. This cap-like body may be a shape close to a cylinder. 
         [0014]    Yet another characteristic of the liquid-mixing infusor of this disclosure is that the chamber is formed as a cylinder with both ends open, an operation portion is allowed to extend to the outside of the chamber from the bottom opening of the chamber, at the same time, a cap-shaped body is attached at the top opening of the chamber, and the branching portion is installed inside the cap-shaped body. Furthermore, in this case, the operation portion is preferably made movable along a portion of a specified range at the periphery of the bottom opening of the chamber, and the portion of the operation portion outside the movement range is preferably extended downward beyond the bottom end of the operation portion. 
         [0015]    Accordingly, the branching portion positioned at the upper portion of the liquid-mixing infusor can be held in a fixed state against the chamber, and, consequently, it is possible to stabilize the flow path formed on the side of the branching portion. Furthermore, by installing an extension at the bottom opening of the chamber, it is possible to attach the liquid-mixing infusor to an installation part when it is extended. As a result, the operation portion does not cause any interference at the time of installation of the liquid-mixing infusor on an installation part, and at the same time, the operation when the liquid-mixing infusor is installed on the installation part becomes easy. 
         [0016]    Still another characteristic of the liquid-mixing infusor of this disclosure is that the valve has a pair of blocking sections blocking in a specific direction between the pair of branch tubes and the chamber when the valve is installed inside the chamber, and pair of depressed sections for connecting between the pair of branch tubes and the chamber when the valve is allowed to rotate about 90° from the specific direction; and furthermore, the widths of the pair of depressed portions along the rotational direction are set to be different, allowing only one of the pair of branch tubes to be connected to the chamber when the valve is allowed to rotate by a specific angle smaller than about 90° from the specific direction. 
         [0017]    In this case, it is possible to configure the valve, for example, by installing a pair of depressed connecting sections having different sizes in the width direction for connection between the pair of branch tubes and the chamber on both sides with the central axis between them in the cylinder, allowing the unchanged other portions of the cylinder to form a pair of blocking sections blocking the pair of branch tubes and chamber, respectively. Furthermore, the pair of depressed connecting sections can be connected through the branching portion. In addition, the size difference in this case between the pair of the depressed connecting sections is set so that the small depressed connecting section is allowed to be movable with one branch tube and the chamber connected within the range in which the large depressed connecting section is movable with the other branch tube and chamber being connected. Accordingly, it is possible to carry out flow path switching reliably with a simple structure. 
         [0018]    Furthermore, still another characteristic of the liquid-mixing infusor of this disclosure is that the valve has a pair of blocking sections blocking in a specific direction between the pair of branch tubes and the chamber when the valve is installed inside the chamber, and a pair of depressed sections connecting between the pair of branch tubes and the chamber when the valve is allowed to rotate about 90° from the specific direction; and furthermore, the positions of the pair of depressed connecting sections are shifted from the portions of the outer circumference of the valve crossing the hypothetical line perpendicular to the central axis of the valve, allowing only one of the pair of branch tubes to be connected to the chamber when the valve is allowed to rotate by a specific angle smaller than about 90° from the specific direction. 
         [0019]    In this case, for example, the portions facing the opening of the pair of branch tubes at the pair of depressed connecting sections are allowed to be larger than the openings of the pair of branch tubes, and at the same time, the positions of the depressed connecting sections are allowed to be displaced from two sides at the periphery of the valve with the central axis of the valve in between. Furthermore, the widths of the pair of depressed connecting sections along the rotational direction are set to be identical, and when the front edge portion of one depressed connecting portion faces the opening of one branch tube, and this depressed connecting portion is connected to this branch tube, the front end portion of the other depressed connecting portion faces the opening of the other branch tube, and the other depressed connecting portion is connected to the other branch tube. 
         [0020]    Accordingly, a depressed connecting section is blocked when the valve is rotated so that the rear edge side of the other depressed connecting section faces the opening of a branch tube connecting the depressed connecting section to the branch tube. Furthermore, the other depressed connecting section described above continues to be connected to the other branch tube by rotating the valve so that the rear edge portion of the above other depressed section faces the opening of the other branch tube, and the depressed section described above is blocked. As a result, it is also possible to switch the flow path reliably with a simple structure. 
         [0021]    Furthermore, by setting the widths of pair of the depressed connecting sections to be different, it is also possible to allow only one of the pair of depressed connecting sections or both to be connected to the chamber or block both by suitably adjusting the position relation of the pair of branch tubes and openings. Incidentally, the fact that the positions of the pair of depressed connecting sections are shifted in this case from the portions of the outer circumference of the valve crossing a hypothetical line means that when the center of one depressed connecting portion along the circumferential direction is on a hypothetical line perpendicular to the central axis of the valve, the center of the other depressed connecting section is not positioned on a hypothetical line perpendicular to the central axis of the valve. 
         [0022]    Moreover, another characteristic of the liquid-mixing infusor of this disclosure is that the circumferential surface of the chamber has positioning bosses installed, and at the same time, the operation portion has stops installed to stop the valve at a specified position by allowing it to be engaged with the positioning bosses. Accordingly, the rotary portion can be reliably stopped at the specified position allowing the valve to carry out flow path switching accurately. 
         [0023]    Finally, still another characteristic of the liquid-mixing infusor of this disclosure is that the branching portion is allowed to include roughly cylindrical branch tubes installed on the top opening side of the chamber, and rubber plugs which are installed inside the branch tubes and capable of allowing insertion tubes to pass through. Accordingly, the flow path of the branching portion formed above the chamber can be connected to or blocked from the inside of the chamber by a simple method. Furthermore, as an insertion tube in this case, it is possible to use a connector insertion portion, male luer of a connector or syringe or needle such as needle for injection, dull needle, Furthermore, if the tip of such an insertion tube is not sharp, the rubber stopper may have a slit for inserting an insertion tube. 
     
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0024]    The present disclosure will be explained by way of example only with reference to the accompanying drawings in which: 
           [0025]      FIG. 1  is a plan view of a liquid-mixing infusor of the first embodiment of this disclosure; 
           [0026]      FIG. 2  is a side view of the liquid-mixing infusor of the first embodiment; 
           [0027]      FIG. 3  is a front view of the liquid-mixing infusor of the first embodiment; 
           [0028]      FIG. 4  is a cross section of  FIG. 2  along the line  4 - 4 ; 
           [0029]      FIG. 5  is a cross section of  FIG. 1  along the line  5 - 5 ; 
           [0030]      FIG. 6  is a cross section showing the liquid-mixing infusor in a state of the valve rotated in the counterclockwise direction; 
           [0031]      FIG. 7  is a cross section showing the liquid-mixing infusor in a state of the valve rotated in the clockwise direction; 
           [0032]      FIG. 8  is a plan view showing the liquid-mixing infusor in a state of the operation portion rotated in the counterclockwise direction; 
           [0033]      FIG. 9  is a plan view showing the liquid-mixing infusor in a state of the operation portion rotated in the clockwise direction; 
           [0034]      FIG. 10  is a plan view of a liquid-mixing infusor of the second embodiment of this disclosure; 
           [0035]      FIG. 11  is a front view of the liquid-mixing infusor of the second embodiment; 
           [0036]      FIG. 12  is a side view of the liquid-mixing infusor of the second embodiment; 
           [0037]      FIG. 13  is a cross section of  FIG. 10  along the line  13 - 13 ; 
           [0038]      FIG. 14  is a plan view showing the liquid-mixing infusor in a state of the operation portion rotated in the counterclockwise direction; 
           [0039]      FIG. 15  is a plan view showing the liquid-mixing infusor in a state of the operation portion rotated in the clockwise direction; 
           [0040]      FIG. 16  is a cross section of a liquid-mixing infusor of the third embodiment; 
           [0041]      FIG. 17  is a cross section showing the liquid-mixing infusor in a state of the valve rotated in the counterclockwise direction from the state of  FIG. 16 ; and 
           [0042]      FIG. 18  is a cross section showing the liquid-mixing infusor in a state of the valve rotated in the clockwise direction from the state of  FIG. 16 . 
       
    
    
     DETAILED DESCRIPTION 
       [0043]    A liquid-mixing infusor as the first embodiment of this disclosure is explained in detail by using drawings as follows.  FIGS. 1-3  are drawings showing a liquid-mixing infusor A of this embodiment, and this liquid-mixing infusor A includes a liquid-mixing infusor main body  10  and rotary portion  20 . The liquid-mixing infusor main body  10  includes a chamber  11  formed as a cylinder having a short length in the axial direction and vertically disposed axial direction, confluent branching portion  12  formed above the chamber  11  (see  FIG. 5 ) and a pair of downstream and upstream branch tubes  13  and  14 , respectively connected to two sides of the chamber  11  at its peripheral surface and extended coaxially maintaining an angle of 180°. 
         [0044]    The main portion of the chamber  11  forms a bottomed cylinder with its bottom closed and top open, and on its peripheral surface in the circumferential direction, handling extrusions  15   a ,  15   b ,  15   c  and  15   d  are formed. The handling extrusions  15   a ,  15   b ,  15   c  and  15   d  extend from the peripheral surface of the chamber in four directions, and their tips extend in external directions perpendicular to the axial directions of the downstream branch tube  13  and upstream branch tube  14 . As shown in  FIG. 4  and  FIG. 5 , the portions facing each other at about the center of the axial direction of the chamber  11  have two connection holes  16   a  and  16   b , respectively. 
         [0045]    A connection hole  16   a  is formed between the handling extrusions  15   a  and  15   b , and a connection hole  16   b  is formed between the handling extrusions  15   c  and  15   d . The portion of the chamber  11  corresponding to the connection hole  16   a  has the downstream branch tube  13  installed, and through the connection hole  16   a , the inside of the chamber  11  and flow path  13   a  formed inside the downstream branch tube  13  are connected. Furthermore, the portion of the chamber  11  corresponding to the connection hole  16   b  has the upstream branch tube  14  installed, and through the connection hole  16   b , the inside of the chamber  11  and flow path  14   a  formed inside the upstream branch tube  14  are connected. 
         [0046]    The downstream branch tube  13  is formed together with the chamber  11  as a single body, and it includes a base end  13   b  positioned on the side of the chamber  11  and male luer  13   c  positioned on the tip side and made thinner than the base end  13   b . The male luer  13   c  is formed tapered towards the tip end side from the side of the base end  13   b . In the border between the base end  13   b  and male luer  13   c  on the circumferential surface of the downstream branch tube  13 , an extrusion  13   d  is formed along the circumference. 
         [0047]    Moreover, the upstream branch tube  14  is formed integrally with the chamber  11 . The downstream side of a flow path  14   a  formed inside (side of the chamber  11 ) is formed tapered with the diameter on the side of the connection hole  16   b  set small but increasing as it moves away from the connection hole  16   b . Furthermore, the upstream side of the flow path  14   a  is formed also tapered with a gradually increasing diameter as it approaches the opening of the upstream branch tube  14 . At the circumference of the opening of the upstream branch tube  14 , a screw for connection  14   b  is formed. On the peripheral surface of the chamber  11  between the handling extrusions  15   a  and  15   d , small positioning bosses  17   a  and  17   b  extending in the vertical direction are formed with spacing so as to partition the distance between the handling extrusions  15   a  and  15   d  into three equal portions. 
         [0048]    Similarly, on the peripheral surface of the chamber  11  between the handling extrusions  15   b  and  15   c , small positioning bosses  18   a  and  18   b  extending in the vertical direction are formed with spacing so as to partition the distance between the handling extrusions  15   b  and  15   c  into three equal portions. Furthermore, on the top end portion of the inner circumferential surface of the chamber  11 , an annular catch  11   a  for a depressed portion is formed, and the rotary portion  20  is installed in a freely rotatable manner on this catch  11   a . Incidentally, the confluent branching portion  12  constitutes a portion of the liquid-mixing infusor of main body  10 , but as explained later, it is incorporated in the rotary portion  20 . 
         [0049]    The rotary portion  20  includes a valve  21  and an operation portion  25  connected to the top end of the valve  21 . The valve  21  is installed inside the chamber  11 , and by operating the operation portion  25 , it is rotatable in the periaxial direction inside the chamber  11 . The outer shape of this valve  21  is formed in an approximately cylindrical shape. The two sides of the cylinder with its axis in between have depressed connecting sections  22  and  23  formed extending from the top to the bottom side of the lateral surface. The depressed connecting section  22  includes a top depression  22   a  consisting of the top side and connection hole  22   b  penetrating through a portion between the bottom of the top depression  22   a  and peripheral surface of the valve  21 . 
         [0050]    In the case of peripheral surface of the top depression  22   a , the plane positioned on the outer peripheral side of the valve  21  is formed on the arc-shaped curvature along the peripheral surface of the valve  21 , and the surface positioned at the middle side of the valve  21  is formed as a conical surface with the top end being close to the center of the valve  21  but coming away from the center of the valve  21  downwards. In addition, the width of the connection hole  22   b  along the circumferential direction is set to be slightly larger than three times the diameter of the connection hole  16   a , and the vertical length of the connection hole  22   b  is set about the same as the diameter of the connection hole  16   a.    
         [0051]    Furthermore, the depressed connecting section  23  includes a top depression  23   a  consisting of the top side and connection hole  23   b  penetrating through a portion between the bottom of the top depression  23   a  and peripheral surface of the valve  21 . In the case of peripheral surface of the top depression  23   a , the surface positioned on the outer peripheral side of the valve  21  is formed on the arc-shaped curvature along the peripheral surface of the valve  21 , and the surface positioned at the middle side of the valve  21  is formed as a conical surface with the top end being close to the center of the valve  21  but coming away from the center of the valve  21  downwards. In addition, the diameter of the connection hole  23   b  is set about same as that of the connection hole  16   b.    
         [0052]    Therefore, a vertical wall  24   a  with conical surface on both sides is formed extending in the radial direction between the depressed connecting sections  22  and  23  in the valve  21 , and at the two sides of this vertical wall  24   a , a pair of blocking sections  24   b  and  24   c  constituting a portion of the periphery  21   a  of the valve  21  are formed. Namely, the valve  21  includes the vertical wall  24   a , a pair of blocking sections  24   b  and  24   c , peripheral side  21   a  and plane bottom  21   b , and if the connection hole  23   b  is allowed to match with the connection hole  16   b , the flow path  14   a  of the upstream branch tube  14  and the inside of the chamber  11  (space between the chamber  11  and valve  21 ) are connected. In this case, the connection hole  16   a  is positioned at the center portion in the width direction of the connection hole  22   b , and the inside of the chamber  11  and the flow path  13   a  of the downstream branch tube  13  are connected. 
         [0053]    Consequently, the upstream branch tube  14  and downstream branch tube  13  are connected through the chamber  11 , and if a drug solution is injected into the flow path  14   a  of the upstream branch tube  14 , the drug solution accumulates in the depressed connecting section  23 . Subsequently, when the liquid level of the drug solution is above the top end of the vertical wall  24   a , the solution flows to the depressed connecting section  22  and to the flow path  13   a  of the downstream branch tube  13  though the connection hole  22   b . In this case, the back flow of the drug solution is prevented by the vertical wall  24   a , and at the same time, the drug solution is allowed to pass through the top portion of the chamber  11  preventing any air from accumulating inside the chamber  11 . 
         [0054]    Furthermore, as shown in the plan view of  FIG. 6 , the valve  21  is allowed to rotate by a specific angle in the counterclockwise direction from the state shown in  FIG. 4 , thus, one end portion in the width direction of the connection hole  22   b  is positioned at one end portion of the connection hole  16   a  while sustaining the state of connection between the connection hole  22   b  and connection hole  16   a , and the connection hole  16   b  is blocked by the blocking section  24   c . Consequently, the chamber  11  and downstream branch tube  13  are connected, and the upstream branch tube  14  and chamber  11  are blocked. Similarly as shown in  FIG. 7 , the valve  21  is allowed to rotate by a specific angle in the clockwise direction from the state of  FIG. 4 , thus, the other end portion in the width direction of the connection hole  22   b  is positioned at the other end of the connection hole  16   a  while sustaining the state of connection between the connection hole  22   b  and connection hole  16   a , and the connection hole  16   b  is blocked by the blocking section  24   b.    
         [0055]    Therefore, chamber  11  and downstream branch tube  13  are connected, and the upstream branch tube  14  and chamber  11  are blocked. Furthermore, although not shown in the figures, the connection holes  16   a  or  16   b  can be blocked with the blocking sections  24   b  or  24   c  by allowing the valve  21  to rotate in the counterclockwise direction from the state of  FIG. 6  or allowing the valve  21  to rotate in the clockwise direction from the state of  FIG. 7 . As a result, both upstream branch tube  14  and chamber  11  and downstream branch tube  13  and chamber  11  can be blocked. 
         [0056]    The top end portion of the valve  21  has a catch portion  21   c  allowed it to be engaged with the catch  11   a  of the chamber  11  rotatably formed along the circumference, and the valve  21  is rotatable against the chamber  11  when catching portion  21   c  is engaged with the catch  11   a . The top peripheral portion of the valve  21  is formed at a catch part  21   d  extruded outwards, the inside of which is a catching depression, and the outside of which is a catching extrusion. 
         [0057]    The operation portion  25  is installed at the upper circumference of the valve  21 , and together with the valve  21 , it is rotatable against the chamber  11 . This operation portion  25  includes a part separate from the valve  21 , and it is configured as a tapered cylinder (cap-shaped body) with the diameter gradually reduced upwards from the side of the valve  21 . Furthermore, in a plan view, operation portion  25  has an oval shape. At the bottom end of the inner peripheral surface, operation portion  25  has a catch portion  25   a  formed, and this catch portion  25   a  is allowed to engage with the catch portion  21   c  of the valve  21  connecting the operation portion  25  to the valve  21 . 
         [0058]    Moreover, a pair of thin plate-shaped stops  26   a  and  26   b  extends downwards from two ends along the axle of the oval at the bottom circumferential portion of the operation portion  25 . The stop  26   a  is movably configured along the peripheral surface of the chamber  11  between the handling extrusions  15   a  and  15   b  and stoppable between the handling extrusion  15   a  and positioning boss  17   a , positioning bosses  17   a  and  17   b , and positioning boss  17   b  and handling extrusion  15   d , respectively. Furthermore, together with the movement or stopping of the stop  26   a , the stop  26   b  is moved along the peripheral surface of the chamber  11  between the handling extrusions  15   b  and  15   c  or stopped between the handling extrusion  15   b  and positioning boss  18   a , positioning bosses  18   a  and  18   b , and positioning boss  18   b  and handling extrusion  15   c , respectively. 
         [0059]    A linear extrusion  27   a  is formed from the bottom center on the surface of the stop  26   a  to the upper surface of the operation portion  25 , and a line extrusion  27   b  is formed from the bottom center on the surface of the stop  26   b  to the upper surface of the operation portion  25 . As shown in  FIGS. 8 and 9  these line extrusions  27   a  and  27   b  are used to confirm the position from the top when the operation portion  25  is used for rotation. Furthermore, the position of the operation portion  25  in the periaxial direction is confirmed by using the stops  26   a  and  26   b  and line extrusions  27   a  and  27   b  and by inspection from the side of the liquid-mixing infusor A. 
         [0060]    The positions of the line extrusions  27   a  and  27   b  in a plan view are set positions along the length direction passing the center in the width direction of the vertical wall  24   a  of the valve  21 . Therefore, the periaxial position of the valve  21  can be confirmed also from the positions of the line extrusions  27   a  and  27   b .  FIG. 6  shows the valve  21  inside the liquid-mixing infusor main body  10  when the line extrusions  27   a  and  27   b  take the positions shown in  FIG. 8 , and  FIG. 7  shows the valve  21  inside the liquid-mixing infusor main body  10  when the linear extrusions  27   a  and  27   b  take the positions shown in  FIG. 9 . Furthermore,  FIG. 4  shows the valve  21  inside the liquid-mixing infusor main body  10  when the linear extrusions  27   a  and  27   b  take the positions shown in  FIG. 1 . The top portion of the operation portion  25  is formed cylindrical, and its peripheral surface has a thread  25   b  formed. In addition, the top end plane of the operation portion  25  has an opening  25   c  installed at its center. 
         [0061]    The confluent branching portion  12  includes a confluent branch tube  28  roughly cylindrical in shape installed inside the operation portion  25  and rubber stopper  29  made of natural or synthetic rubber and installed at the top opening of the confluent branch tube  28 . The confluent branch tube  28  is a short cylinder tapered upwards with the diameter gradually reduced, and it is fixed on the valve  21  by engagement with the inner side catch recess at the catching part  21   d  of the valve  21 . Furthermore, the outer diameter of the top of the confluent branch tube  28  is slightly smaller than the inner diameter of the top portion of the operation portion  25 . 
         [0062]    The rubber stopper  29  includes a thick disc-shaped stopper main body  29   a  and belt-shaped attachment pieces  29   b  and  29   c  extending from the two upper sides of the stopper main body  29   a . The stopper main body  29   a  is pushed into the confluent branch tube  28  from the top opening of the confluent branch tube  28 , and the rubber stopper  29  is fixed by fixing the operation portion  25  at the outside of the confluent branch tube  28  with attachment pieces  29   b  and  29   c  set along the peripheral surface of the confluent branch tube  28 . Namely, the operation portion  25  is fixed by pressing the attachment pieces  29   b  and  29   c  against the side of the confluent branch tube  28 , and at the same time, the peripheral portion of the top surface of the stopper main body  29   a  is pressed also against the confluent branch tube  28 , preventing the stop from coming off. 
         [0063]    Furthermore, this rubber stopper  29  has a slit  29   d  installed forming a flow path of the confluent branching portion  12  passing through the inner side of the confluent branch tube  28  and outer side of the confluent branch tube  28 . this slit  29   d  is in its closed state because of the elastic force of the rubber stopper  29  when the flow path of the confluent branching portion  12  is not used. Furthermore, if the flow path of the confluent branching portion  12  is used, a suitable connector (not shown in the figures) is inserted into the slit  29   d  to form a flow path. This connector is equipped with a male luer with a flow path formed inside, and this male luer is inserted into the slit  29   d  of the rubber stopper  29  to connect the connector and inside of the confluent branch tube  28 . Furthermore, in this case, the peripheral surface of the male luer comes into close contact with the inner surface of the slit  29   d  because of the elasticity of the rubber stopper  29 . 
         [0064]    When administering a required drug solution to a patient (not shown) with this configuration, the rear end portion of an infusion tube (not shown) with an attached needle remaining inserted in the patient is connected to the downstream branch tube  13 . On the other side, a male luer attached to the end of an infusion tube extended from a container containing the drug solution to be administered to the patient is connected to the upstream branch tube  14 . With the indwelling needle attached to the body, the operation portion  25  is operated sending the drug solution from the container to the patient to administer the drug solution to the patient. Furthermore, if another drug solution is to be administered to the patient in addition to the drug solution administer from the container, this other drug solution is injected into the chamber  11  from the confluent branching portion  12  through an infusion tube connected to a connector. 
         [0065]    Namely, if the operation portion  25  is operated with the connector attached to the confluent branching portion  12  to obtain the state shown in  FIG. 8  or  FIG. 9 , the connector and downstream branch tube  13  are connected inside the chamber  11  through the recessed connecting portion  22 . In this case, the blocking section  24   c  or  24   b  of the valve  21  blocks the connection hole  16   b , and as a result, the upstream branch tube  14  is blocked against the inside of the chamber  11 . This state can be confirmed by observing the positions of the strip extrusions  27   a  and  27   b  preventing the occurrence of any erroneous operation. Furthermore, the stop  26   a  is stopped in at a position between the handling extrusion  15   a  and positioning boss  17   a  or positioning both  17   b  and handling extrusion  15   d , and at the same time, the stop  26   b  is stopped at a position between the positioning boss  18   b  and handling extrusion  15   c  or handling extrusion  15   b  and positioning boss  18   a . Consequently, the rotary portion  20  is reliably fixed on the prescribed position. 
         [0066]    If the operation portion  25  is operated to achieve the state shown in  FIG. 1  and  FIG. 2 , the connector, downstream branch tube  13  and upstream branch tube  14 , are respectively connected through the chamber  11 . In this case, as shown in  FIG. 4 , the stop  26   a  is stopped at a position between the positioning bosses  17   a  and  17   b , and the stop  26   b  is stopped at a position between the positioning bosses  18   a  and  18   b . Consequently, the rotary portion  20  is reliably fixed at a prescribed position. Furthermore, before inserting and leaving the indwelling needle in the patient, a small amount of the drug solution is discharged from the tip of the needle. As a result, any air present in the flow path together with the drug solution can be expelled. Furthermore, the liquid-mixing infusor A may be attached to an installation board, before using it. 
         [0067]    As described above, the liquid-mixing infusor A of this embodiment is equipped with the valve  21  rotatable in the periaxial direction inside the chamber  11  and operation portion  25  connected to the valve  21  and positioned above the chamber  11 . When the operation portion  25  is allowed to be rotated in an optional direction to achieve the state shown in  FIG. 1 ,  FIG. 8  or  FIG. 9 , the valve  21  allows the connection or blocking section among the downstream branch tube  13 , upstream branch tube  14  and chamber  11 , respectively. Therefore, the opening and closing operations among the downstream branch tube  13 , upstream branch tube  14  and chamber  11  can be carried out conveniently, and at the same time, the operation can be carried out easily with a single hand. Furthermore, by inserting a connector into the rubber stopper  29  of the confluent branching portion  12 , it is possible to connect the connector to the downstream branch tube  13  and upstream branch tube  14  or to the downstream branch tube  13 . As a result, it becomes possible to provide a patient with one or two kinds of drug solutions. 
         [0068]    If the drug solution is allowed to flow from the upstream branch tube  14  to the downstream branch tube  13 , the drug solution is accumulated once inside the recess  23  for connection, subsequently flows to the side of the recess  22  for connection by going over the top end of the vertical wall  24   a  and to the flow path  13   a  of the downstream branch tube  13  through the connection hole  22   b . In this case, the vertical wall  24   a  prevents the drug solution from back-flow, and at the same time, by allowing the drug solution to pass through the upper portion of the chamber  11 , prevents any air from accumulating inside the chamber  11 . Therefore, the drug solution is properly administered to the patient. 
         [0069]    Since the bottom of the chamber  11  is formed as a flat plane, it is possible to install a plurality of liquid-mixing infusors A on an installation plate, and a plurality of infusion tubes may be connected to each liquid-mixing infusor A. Accordingly, it is possible to feed a plurality of drug solutions concomitantly into the body. Furthermore, if the liquid-mixing infusor A is installed on an installation plate, the operation portion  25  can be operated easily with a single hand. In addition, the operation portion  25  is positioned at the top portion of the liquid-mixing infusor A, it is easily visible, and the operating position of the valve  21  can be easily confirmed. 
         [0070]    Furthermore, the peripheral surface of the chamber  11  has positioning bosses  17   a , installed, and at the same time, the operation portion  25  can be equipped with the stops  26   a  and  26   b . As a result, the rotary portion  20  can be reliably stopped at a prescribed position enabling accurate flow path switching by the valve  21 . In addition, any undesired movement of the rotary portion  20  switching the flow path is effectively prevented. The stops  26   a  and  26   b  have corresponding strip extrusions  27   a  and  27   b , respectively reducing the chance of the operator making any erroneous operation to connect or block an incorrect flow path. In addition, the confluent branching portion is allowed to include the confluent branch tube  28  and rubber stopper  29  equipped with the slit  29   d , and consequently, the flow path of the confluent branching portion  12  formed at the top portion of the chamber  11  can be connected to or blocked against the inside of the chamber  11  with simple procedures. 
         [0071]      FIG. 10-FIG .  12  shows a liquid-mixing infusor B of the second embodiment of this disclosure. This liquid-mixing infusor B includes a liquid-mixing infusor main body  30  and rotary portion  40 . The liquid-mixing infusor main body  30  has a chamber  31 , which is a cylinder with top and bottom ends opened as shown in  FIG. 13 . The top end periphery of the chamber  31  has an annular catch  31   a  including an extrusion, and at a position slightly lower than this, catch  31   a  is on the inner circumferential surface of the chamber  31 , and a ring shaped extrusion  32  protruding inwards is formed. 
         [0072]    Below this extrusion  32  formed on the inner circumferential surface of the chamber  31 , an annular catch  31   b  including an extrusion is formed, and the rotary portion  40  is installed so as to be freely rotatable on this catch  31   b . Furthermore, the outer periphery of the main body portion of the chamber  31  has handling extrusions  35   a ,  35   b ,  35   c  and  35   d  formed with spacing between them in the circumferential direction. These handling extrusions  35   a ,  35   b ,  35   c  and  35   d  extend downwards from the main body portion of the chamber  31 , and thus they are longer in the vertical direction than the handling extrusions  15   a ,  15   b ,  15   c  and  15   d  described above for the first embodiment. Furthermore, the bottom end portions of the section between the handling extrusions  15   a  and  15   b  and handling extrusions  15   c  and  15   d  are extended to the same position as the bottom ends of the handling extrusions  15   a ,  15   b ,  15   c  and  15   d.    
         [0073]    The rotary portion  40  includes a valve  41  and pair of operation portions  45  (only one operation portion  45  shown in the figure) connected to the bottom end portion of the valve  41 . The top end portion at the peripheral plane of the valve  41  has a catching portion  41   a  formed along the circumference including a recess engaged with the catch  31   b  of the chamber  31  in a rotatable state, and the valve  41  is rotatable against the chamber  31  with the catching portion  41   a  allowed to engage with the catch  31   b . Furthermore, the top end of the valve  41  comes into close contact in a liquid-tight manner with the bottom surface of the extrusion  32  of the chamber  31 . 
         [0074]    Furthermore, the operation portions  45  include respectively thin plates extending upwards along the peripheral surface of the chamber  31  from both sides of the circumference of the bottom surface  41   b  of the valve  41 . At the center portions in the width direction on the surface of the pair of the operation portions  45 , strip extrusions  47   a  and  47   b  extending vertically are respectively formed. Namely, the operation portions  45  are used to carry out a rotary operation of the valve  41 , and at the same time, acts as steps restricting the rotary angle of the rotary portion  40  similarly to the stops  26   a  and  26   b  described above for the first embodiment. 
         [0075]    Furthermore, the upper periphery of the chamber  31  has a cap  42  having roughly the same structure as that of the operation portion  25  in the above embodiment attached. The inner circumferential lower end of this cap  42  has a catching portion  42   a  including a recess engageable with the catch  31   a  formed, and the cap  42  is fixed on the chamber  31  by allowing the catching portion  42   a  to engage with the catch  31   a . Furthermore, a confluent branch tube  48  is attached to the chamber  31  with the end allowed to engage with the top plane of the extrusion  32  and inner circumferential plane of the chamber  31 . The configurations of other parts in chamber  31  of this liquid-mixing infusor B are the same as those in the liquid-mixing infusor A described above for the first embodiment. Therefore, the same numerals are used for the same parts and any further explanations are omitted. 
         [0076]    To administer a specific drug solution to the patient with this configuration, the downstream branch tube  13  is connected to an infusion tube with an indwell needle attached, and at the same time, the upstream branch tube  14  is connected to an infusion tube extended from a container containing the drug solution, similarly to the first embodiment described above. With the indwell needle inserted and remaining in the patient&#39;s body, the operation portions  45  are operated sending the drug solution from its container towards the patient to carry out administration of the drug solution to the patient. In this case, the two operation portions  45  are operated with a hand holding them from two sides. In addition, if another drug solution is to be provided to the patient in addition to the above drug solution fed from the container, the other drug solution is injected inside the chamber  31  from the confluent branching portion  12  through an infusion tube connected to the connector. 
         [0077]    In this case, the operation portions  45  are operated with the confluent branching portion  12  having a connector remaining attached to achieve the state shown in  FIG. 14  or  FIG. 15 . As a result, the connector and the downstream branch tube  13  are connected through the connecting recess  22  inside the chamber  31 . Incidentally, if the state of  FIG. 14  is obtained by operating the operation portions  45 , the lateral cross section of the liquid-mixing infusor B becomes same as that of  FIG. 6 , and if the state of  FIG. 15  is obtained by operating the operation portions  45 , the lateral cross section of the liquid-mixing infusor B becomes the same as that of  FIG. 7 . Furthermore, if the operation portions  45  are operated to obtain the state of  FIG. 10  and  FIG. 11 , the connector, downstream branch tube  13  and upstream branch tube  14  are connected through the chamber  31 . 
         [0078]    In the liquid-mixing infusor B, the confluent branching portion  12  positioned at the top portion is fixed to the chamber  31  as explained above, the flow path formed inside the confluent branching portion  12  can be stabilized. Furthermore, the bottom ends of the handling extrusions  35   a ,  35   b ,  35   c  and  35   d  and a portion of the bottom portion of the chamber  31  are extended downwards from the bottom end of the main body portion of the chamber  31 , it is possible to attach the liquid-mixing infusor B to an installation plate with the handling extrusions  35   a , being fixed on the installation plate. Consequently, the operation portions  45  do not interfere with the installation of the liquid-mixing infusor B on an installation plate, and when the liquid-mixing infusor B is installed on an installation plate, the operation of the operation portions  45  becomes easy. Other reactions and effects of this liquid-mixing infusor B are same as those of the liquid-mixing infusor A described above. 
         [0079]      FIGS. 16-18  show a liquid-mixing infusor C as the third embodiment of this disclosure. This liquid-mixing infusor C has a vertical cross section along the length direction the same as that shown in  FIG. 13 . In this liquid-mixing infusor C, a valve  51  is formed in a roughly cylindrical shape with recessed connecting sections  52  and  53  formed on two sides with the center axis of the cylinder in between. The widths of the recessed connecting sections  52  and  53  along the circumferential direction of valve  51  are set about equal, and the positions of the recessed connecting sections  52  and  53  are slightly shifted from the two sides with the center axis of the valve  51  in between on the peripheral surface of the valve  51 . 
         [0080]    Namely, the recessed connecting section  52  includes, similarly to the recessed connecting section  22 , an upper recess  52   a  on the top side and connection hole  52   b  penetrating through the bottom portion of the upper recess  52   a  and peripheral surface of the valve  51 . The width of the connection hole  52   b  along the circumferential direction is set to about twice as long as the diameter of the connection hole  56   a , and the vertical length of the connection hole  52   b  is set about the same as the diameter of the connection hole  56   a . Furthermore, the recessed connecting section  53  includes, similarly to the recessed connecting section  23 , an upper recess  53   a  on the top side and connection hole  53   b  penetrating through the bottom portion of the upper recess  53   a  and peripheral surface of the valve  51 . The width of the connection hole  53   b  along the circumferential direction is set to about twice the diameter of the connection hole  56   b , and the vertical length of the connection hole  53   b  is set about the same as the diameter of the connection hole  56   b.    
         [0081]    Furthermore, the lateral cross-section of the recessed connecting section  52  in plan view is formed in a roughly square shape extending from the side of the vertical wall  54   a  towards the peripheral side twisted in the clockwise direction, and the lateral cross-section of the recessed connecting section  53  in plan view is formed in a roughly square shape extending from the side of the vertical wall  54   a  towards the peripheral side twisted in the counterclockwise direction. In addition, as shown in  FIG. 16 , when the front side portion of the recessed connecting section  52  (bottom side portion in  FIG. 16 ) is allowed to face the connection hole  56   a , the front side portion of the recessed connecting section  53  faces the connection hole  56   b . Therefore, if the center of the peripheral side portion of the recessed connecting section  52  along the circumferential direction is allowed to be positioned on a hypothetical line a perpendicular to the central axis of the valve  51 , the position of the center of the peripheral side portion of the recessed connecting section  53  is remote from the hypothetical line a. 
         [0082]    If the valve  51  is allowed to rotate in the counterclockwise direction from the state of  FIG. 16  to the state of  FIG. 17 , the rear side portion of the recessed portion connection  52  continues to face the connection hole  56   a , but the recessed connecting section  53  is blocked. Furthermore, if the valve  51  is allowed to rotate in the clockwise direction from the state of  FIG. 16  to the state of  FIG. 18 , the rear side portion of the recessed connecting section  53  continues to face the connection hole  56   b , but the recessed connecting section  52  is blocked. According to this configuration, it is possible to connect both paths between the recessed connecting section  52  and connection hole  56   a  and between recessed connecting section  53  and connection hole  56   b , block both of them or alternatively connect only one of the paths between the recessed connecting section  52  and connection hole  56   a  or between recessed connecting section  53  and connection hole  56   b.    
         [0083]    When a specific drug solution is to be administered to the patient with this configuration, the processing is similar to that carried out for the second embodiment described above. If another drug solution is to be mixed with the one from the upstream branch tube  14  by attaching a connector connected to an infusion tube to the confluent branching portion  12 , the other drug solution supplied from the connector side is sent once to the upstream branch tube  14  side, adjusted to a suitable concentration on the upstream branch tube  14  side and subsequently allowed to flow to the downstream branch tube  13  side. In this case, the valve  51  is allowed to rotate connecting the chamber  13  and upstream branch tube  14  through the recessed connecting section  53  as shown in  FIG. 18 , and the path between the recessed connecting section  52  and downstream branch tube  13  is blocked. 
         [0084]    Subsequently, the drug solution is supplied from the connector side to the side of the upstream branch tube  14  through the top branching portion  12  and recessed connecting section  53 , and the drug solution is mixed with the drug solution fed to the upstream branch tube  14  from a container connected to the upstream branch tube  14 . The valve  51  is allowed to rotate subsequently to achieve the state of  FIG. 16  connecting the chamber  31  and upstream branch tube  14  through the recessed connecting section  53 , and at the same time, the chamber  31  and downstream branch tube  13  through the recessed connecting section  52 . 
         [0085]    In the state as described above, the drug solution in a container connected to the upstream branch tube  14  is fed to the upstream branch tube  14 , those two kinds of drug solutions mixed in the upstream branch tube  14  or a nearby portion flow in a mixed state to the side of the downstream branch tube  13  and are administered to the patient. Furthermore, even in the case of this liquid-mixing infusor C used, it is also possible to feed only a drug solution from a container connected to the upstream branch tube  14  to the downstream branch tube  13  or from the connector side to the downstream branch tube  13 . 
         [0086]    According to this liquid-mixing infusor C explained above, a drug solution supplied from the connector side is sent once to upstream branch tube  14  side, mixed with another drug solution fed from a container connected to the upstream branch tube  14 , and the mixture is subsequently administrable to the patient&#39;s body. The flow path after two kinds of drug solutions are mixed and administered to the patient is sufficiently long for a uniform mixture those two kinds of drug solutions. As a result, the two kinds of drug solutions are administered to the patient in a uniformly mixed state. Other actions and effects of this liquid-mixing infusor C are similar to those of the liquid-mixing infusor B described above. 
         [0087]    The liquid-mixing infusor of this disclosure is not necessarily limited to those embodiments described above, and suitable modifications are also possible. For example, in each of the embodiments described above, the rubber stopper  29  is allowed to have the slit  29   d  formed, and a connector is installed in the confluent branching portion  12  by inserting the male luer into the slit  29   d , but instead of using a connector, it is possible to insert a syringe male luer or injection needle into the rubber stopper  29 . If the injection needle is used, it is not necessary to form the slit  29   d  in the rubber stopper  29 . 
         [0088]    It is also possible to install windows for the downstream branch tube  13  and upstream branch tube  14  on the peripheral surface of the chamber  11  and apply indicators showing the state of connection and blocking of the paths between the chamber  11  and downstream branch tube  13 , chamber  11  and upstream branch tube  14 , on the peripheral surface of the valve  21 , thus making it possible to see the indicators through the windows for confirmation. Consequently, the position of the rotary portion can be confirmed reliably. As an indicator in this case, it is possible to use, for example, characters such as “O” for open and “C” for closed. In addition, it is also possible to change the shapes of other portions, materials, suitably to configure the liquid-mixing infusor of this disclosure. 
         [0089]    It will be understood that various modifications and changes in form and detail may be made to the embodiments of the present disclosure without departing from the spirit and scope of the disclosure. Therefore, the above description should not be construed as limiting the disclosure but merely as exemplifications of preferred embodiments thereof. Those skilled in the art will envision other modifications within the scope and spirit of the present disclosure as defined by the claims appended hereto. Having thus described the disclosure with the details and particularity required by the patent laws, what is claimed and desired protected is set forth in the appended claims.