Patent Publication Number: US-6341637-B1

Title: Tube connecting apparatus

Description:
This division of application Ser. No. 08/987,044, filed Dec. 10, 1997 now U.S. Pat. No. 6,026,882 of which is incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a tube connecting apparatus for heating and melting to cut flexible tubes and connecting the tubes by mutually welding the cut end faces thereof. 
     2. Description of the Related Art 
     According to a conventional tube connecting apparatus, two tubes, for instance, to be connected are held in parallel with each other and a cutting plate comprising a plate-like heating element is moved as if to cross the tubes, thereby heating and melting to cut the tubes. The tubes thus held are rotated so that the cut ends will slide on the cutting plate, and then the melted cut ends of the tubes are connected with each other by the withdrawal of the cutting plate. 
     A conventional example of a tube connecting apparatus having the above-described function, particularly a holder for holding tubes, will hereinafter be briefly explained. FIG. 28 is a perspective illustration showing a holder in use in a conventional tube connecting apparatus. 
     The tube connecting apparatus of the conventional example comprises a fixed tube holder  201  which is fixedly secured at all times, and a movable tube holder  202  which is rotatable and movable in the axial direction of tubes. The fixed tube holder  201  and the movable tube holder  202  are provided with grooves  231  and  241  in holder blocks  203  and  204  in which tubes  205  and  206  can be mounted. On the holder blocks  203  and  204 , covers  207  and  208  are rotatably attached by hinges. Therefore, with the rotation of the covers  207  and  208 , the grooves  231  and  241  of the holder blocks  203  and  204  are opened and closed. The fixed tube holder  201  and the movable tube holder  202  are provided with a locking mechanism. The lock mechanism is composed of engaging pawls  271  and  281  protrusively provided on the covers  207  and  208 , and engaging holes  232  and  242  provided by drilling in the holder blocks  203  and  204  which engage with the engaging pawls  271  and  281 . 
     The movable tube holder  202  is set a specific distance off the fixed tube holder  201 , and the grooves  231  and  241  are positioned so as to be aligned on one line. 
     The movable tube holder  202  is provided with rotating means for rotating itself. This rotating means is formed such that the forward end of a crankshaft connected to a driving shaft of a motor  210  is secured to the holder block  204  of the movable tube holder  202 . On the extension M of the driving shaft of the motor  210 , the grooves  231  and  241  formed in the holder blocks  203  and  204  of the fixed tube holder  201  and the movable tube holder  202  are extendedly present, so as to be located on, or in the vicinity of, the tubes  205  and  206  which are charged one over the other within the grooves  231  and  241 . 
     In the case of the conventional tube connecting apparatus of the above-described constitution, first the grooves  231  and  241  are opened by the user of the apparatus by turning the covers  207  and  208  upwards from the holder blocks  203  and  204  of the fixed tube holder  201  and the movable tube holder  202 . Then, the tubes  205  and  206  are set one over the other in the grooves  231  and  241  thus opened upwards. Subsequently the covers  207  and  208  are turned downwards to close the grooves  231  and  241  with the tubes  205  and  206  thus set, and are held down until the engaging pawls  271  and  281  of the covers  207  and  208  are firmly engaged with the engaging holes  232  and  242  formed in the holder blocks  203  and  204 . 
     Subsequently, after thus setting the tubes  205  and  206  on the tube connecting apparatus, the user depresses an unillustrated starting switch to ON, thereby connecting the cut ends of these tubes  205  and  206  by the above-described operation. 
     That is, when the switch is depressed to ON, an unillustrated cutting plate travels between the fixed tube holder  201  and the movable tube holder  202  to cut the tubes  205  and  206 . After the cutting of the tubes  205  and  206 , the movable tube holder  202  is turned 180 degrees up and down through the crankshaft  211  by turning power of the motor  210 . Then, when the cutting plate is withdrawn, the movable tube holder  202  is axially moved by unillustrated moving means by the same amount as the thickness of the cutting plate towards the fixed tube holder  201 , melting to mutually connect the cut ends of the tubes  205  and  206 . At this time, as the tube holder  202  has been turned 180 degrees, the cover  208  faces down and the holder block  204  faces up. 
     Subsequently, the user opens the groove  231  by turning the cover  207  upwards from the holder block  203  of the fixed tube holder  201 . 
     Thereafter, with the starting switch pressed to ON, the movable tube holder  202  is turned 180 degrees by the turning power from the motor  210  through the crankshaft  211 . Then, as the cover  208  of the movable tube holder  202  faces up, the groove  241  is opened by turning the cover  208  upwards from the holder block  204 , and the tubes thus connected are taken out. 
     The conventional tube connecting apparatus, however, has the following problems. 
     In the above-described conventional tube connecting apparatus, as the movable tube holder  202  has turned 180 degrees from the state before jointing, the cover  208  can not turn from the holder block  204  and accordingly the tubes can not be taken out after the tubes  205  and  206  are cut and jointed. 
     To take out the jointed tubes, the groove  231  is opened in advance by turning the cover  207  upwards from the holder block  203  of the fixed tube holder  201 . Next, it is necessary to open the groove  241  of the holder block  204 , after the cover  208  turns to face up, by operating the starting switch to turn the connected tube 180 degrees, together with the movable tube holder  262 , and then to turn the cover  208  further upwards, making operation complicated and requiring much time for pipe connection. 
     Furthermore, in the conventional tube connecting apparatus, as described above, the apparatus automatically cuts and connects the tubes  205  and  206 ; and therefore the user himself is required to carry out setting the tubes  205  and  206  to, and taking out the tubes from, the apparatus. 
     In this case, it becomes necessary to open and close the covers  207  and  208  together with the fixed tube holder  201  and the movable tube holder  202 . However, in order to prevent connection error likely to be caused by misalignment of the tubes  205  and  206 , there is provided lock means which comprises the engaging pawls  271  and  281  and the engaging holes  232  and  242 . Therefore a power is needed to open and close the covers  207  and  208  when the user sets the tubes  205  and  206  on the fixed tube holder  201  and the movable tube holder  202 . To open and close the covers  207  and  208 , about 1.5 to 2 kgf finger tip pressure is required. 
     This degree of pressure is liable to be thought not so great a pressure for a physically sound person, who therefore can easily open and close the covers  207  and  208 . However, the present apparatus is used for connecting a transfer tube connected with the abdominal cavity to a tube connected with a dialysis pack to supply for instance a dialysis solution into the abdominal cavity of a peritoneum dialysis patient. Therefore, it is quite an easy operation to the physically sound person to open and close the covers  207  and  208 . However, it is a hard work to such a physically handicapped person as a peritoneum patient who is weak-sighted or has a low physical strength. 
     Furthermore, in the conventional tube connecting apparatus described above, the tubes  205  and  206  are set one over the other in the grooves  231  and  241  formed in the holder blocks  203  and  204 ; therefore, the lower tube in the grooves  231  and  241 , if pulled first by mistake after connection, will be caught by the upper tube, resulting in such a disadvantage as twist or damage. 
     Furthermore, there also occurs such a problem that if the movable tube holder  202  holding the tubes  205  and  206  is turned, the tubes will twist around the motor  210  mounted outside of the movable tube holder  202  and also around the crankshaft  211  transmitting the power from the motor  210  to the holder block  204 . 
     SUMMARY OF THE INVENTION 
     To cope with such problems or disadvantages stated above, it is an object of the present invention to provide a tube connecting apparatus which has lessened the user&#39;s burden in order to ensure easy handling, and also is capable of preventing interference between driving means and tubes. 
     To accomplish the above-mentioned object, the tube connecting apparatus of the present invention has the following constitution. 
     That is, the tube connecting apparatus of the present invention has a first tube holder and a second tube holder for holding a plurality of flexible tubes, and cutting means for heating and melting to cut the tubes between the first tube holder and the second tube holder while the tubes are as-held in the first tube holder and the second tube holder. Each of the first tube holder and the second tube holder has a holding portion for holding the aforesaid tubes, and grasping means driven so that the tube contact portions of the holding portion will contact, and be apart from, each other, to thereby grasp and release the tubes. One or both holding portions are separable into members having a rotation symmetry in relation to the center of the rotating axis, and are rotatably mounted by rotating means. 
     In the tube connecting apparatus of the present invention of the above-described constitution, the user set tubes in the holding portion formed in the contact portion between a pair of clamps of the first tube holder and the second tube holder which are disposed apart. Thereafter, the pair of clamps grasp the tubes in contact by the grasping means in the holding portion, and then the cutting means inserts between the first tube holder and the second tube holder to heat and melt to cut the tubes. Then, the holding portion is rotated by the aforesaid rotating means to turn the holding portion in which the tubes are grasped, thereby changing the positions of the tubes. Thus the cut ends of different tubes face each other through the cutting means. Thereafter, simultaneously with the withdrawal of the cutting means, the first tube holder and the second tube holder are brought closer to each other by the aforesaid adjusting means, thereby connecting the cut ends of the tubes. That is, the cut ends of different tubes are welded each other. Subsequently the pair of clamps of the first tube holder and the second tube holder are separated by the grasping means to allow the user to take out the connected tubes from the holding portion. 
     In the tube connecting apparatus of the present invention thus constituted, the tubes are reliably grasped in contact with a pair of holding portions operated by the grasping means; then the cutting means inserts between the first tube holder and the second tube holder to melt to cut the tubes. Thereafter the rotating means operates to turn the holding portion, to turn the holding portion grasping the tubes, thereby changing the tube positions. The cut ends of the different tubes face each other through the cutting means. Thereafter, simultaneously with the withdrawal of the cutting means, the first tube holder and the second tube holder are moved close to each other by the adjusting means, thus connected to each other. After thus welding the cut ends of the different tubes each other, the pair of holding portions of the first tube holder and the second tube holder are apart from again by grasping means. 
     In the meantime, for using the tube connecting apparatus, at least two tubes supported by the supporting means are moved to the holding position between the holding portions of the first tube holder and the second tube holder. The user, therefore, is required just to set the tubes to be connected on the supporting means outside of the grasping area of the holding portions within which the holding portions move, and to take the connected tubes out of the supporting means. 
     The tube connecting apparatus of the present invention has the following characteristic that the first tube holder and the second tube holder have holding portions for holding a plurality of tubes previously stated; one or both of the holding portions are separated into rotatable members having a rotation symmetry and are connected with a grasping means driven to move the holding portions into contact with, and away from, each other, and are connected with a rotating means for rotating one or both of the holding portions which are separated into the above-mentioned members of rotation symmetry, and have a supporting means for supporting the above-described at least two tubes together and moving these tubes to inside of the grasping area of the holding portions from outside of the grasping area of the holding portions. 
     In the tube connecting apparatus of the present invention, since it is unnecessary to open and close the cover when setting the tubes on the apparatus, the apparatus has become easier to handle with less burden on the user. 
     Furthermore, in the tube connecting apparatus of the present invention, a series of such operations as grasping, cutting, turning, connecting, and then releasing of grasped tubes are automatically carried out by control means. It, therefore, has become easy to handle the apparatus with reduced user&#39;s burden. 
     Other objects, together with the foregoing, are attained in the embodiments described in the following description and illustrated in the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an external perspective illustration showing a major portion of one embodiment of a tube connecting apparatus of the present invention; 
     FIG. 2 is a front view showing contact surfaces of fixed clamps  21  and  41  of a first tube holder  1  and a second tube holder  2 ; 
     FIG. 3 is a vertical cross sectional view of a fixed clamp  21  and a movable clamp  31  of the first tube holder  1 ; 
     FIG. 4 is a view showing the fixed clamp  21  and the movable clamp  31  with a clamp rotor mounted in a cover member; 
     FIG. 5 is a perspective illustration showing the second tube holder  2 ; 
     FIG. 6 is a perspective illustration showing driving means for driving the tube connecting apparatus; 
     FIG. 7 is a block diagram showing a control unit; 
     FIG. 8 is an external perspective illustration showing the first tube holder and the second tube holder prior to tube setting; 
     FIG. 9 is an external perspective illustration showing the first tube holder and the second tube holder with tubes set in the clamps; 
     FIG. 10 is a view showing the section of the tubes set in the clamps; 
     FIG. 11 is a perspective illustration showing the tubes at the time of cutting; 
     FIG. 12 is an external perspective illustration showing the first tube holder and the second tube holder with the clamp rotor turned; 
     FIG. 13 is a perspective illustration showing the tubes after the clamp-rotor is turned; 
     FIG. 14 is an external perspective illustration showing the first tube holder and the second tube holder after the tubes are taken out; 
     FIG. 15 is an external perspective illustration showing the clamp of the tube connecting apparatus of the second embodiment according to the present invention; 
     FIG. 16 is an external perspective illustration showing fixed clamps  111  and  131  of a first tube holder  101  and a second tube holder  102  of the second embodiment; 
     FIG. 17 is a view showing the interior of a fixed clamp  111  and a movable clamp  121  of the first tube holder  101  of the second embodiment; 
     FIG. 18 is a view showing blocks  112  and  122  of the first tube holder  101  mounted with a clamp rotor of the second embodiment; 
     FIG. 19 is an exterior perspective illustration showing a support  171  of the tube connecting apparatus of the second embodiment; 
     FIG. 20 is a schematic view showing a feed mechanism of a support of the tube connecting apparatus of the second embodiment; 
     FIG. 21 is a schematic view showing the feed mechanism of the support of the tube connecting apparatus of the second embodiment; 
     FIG. 22 is a block diagram showing the control unit of the tube connecting apparatus of the second embodiment; 
     FIG. 23 is a side view showing a clamp of the tube connecting apparatus of the second embodiment; 
     FIG. 24 is a side view showing the clamp of the tube connecting apparatus of the second embodiment; 
     FIG. 25 is a schematic view showing the state of cut tubes; 
     FIG. 26 is a schematic view showing the state of the tubes with the clamp rotor  153  rotated after tube cutting; 
     FIG. 27 is a view showing the tubes after connection; and 
     FIG. 28 is a perspective illustration showing a holder of a conventional tube connecting apparatus. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Next, the first embodiment of a tube connecting apparatus of the present invention will be explained with reference to the accompanying drawings. FIG. 1 is an exterior perspective illustration showing a major portion of the tube connecting apparatus of the present embodiment. The tube connecting apparatus comprises the first tube holder  1  and the second tube holder  2 , which are engaged with an unillustrated body. In the first tube holder  1  and the second tube holder  2 , fixed clamps  21  and  41  are fixedly mounted on bases  11  and  12 ; and movable clamps  31  and  51  movable to, and away from, the fixed clamps  21  and  41  are mounted. On the bases  11  and  12  are formed rail grooves  11   a  and  12   a . On the bottom end of the fixed clamps  21  and  41  and the movable clamps  31  and  51  are formed projecting portions  22 ,  32 ,  42  and  52  which are engaged with the rail grooves  11   a  and  12   a . With the projections  22 ,  32 ,  42  and  52  engaged with the rail grooves  11   a  and  12   a , the fixed clamps  21  and  41  are fixed on the bases  11  and  12  to limit their movement; and the movable clamps  31  and  51  are so mounted as to be movable along the rail grooves  11   a  and  12   a.    
     In the present embodiment, the first tube holder  1  has a later-described rotating mechanism, and the second tube holder  2  is not provided with such a rotating mechanism. FIG. 2 is a front view showing the contact surfaces of the fixed clamps  21  and  41  of the first tube holder  1  and the second tube holder  2 . And FIG. 3 is a view showing the vertical portions of the fixed clamp  21  and the movable clamp  31  of the first tube holder  1 . 
     The fixed clamp  21  and the movable clamp  31  of the first tube holder  1  comprise a pair of cover members  23  and  24  and a pair of cover members  33  and  34 , which form one block as shown in FIG.  1 . The cover members  23  and  24  and the cover members  33  and  34  are of a similar shape and symmetrical. The constitution of the cover members  23  and  33  on one side shown in FIG. 3 will be explained in detail. The cover members  23  and  33  are formed of a plate of specific thickness as shown, and the projections  22  and  32  are formed on the bottom end. 
     Above the projections  22  and  32  are formed rotor mounting portions  25  and  35  in which semi-circular recesses are provided for mounting a clamp rotor  63  (shown in FIG. 1) as a holding portion consisting of a pair of semi-circular rotor pieces  61  and  62 . At the center of the rotor mounting portions  25  and  35  are formed semi-circular cutouts  26  and  36  in such a form that the central part of the clamp rotor  63  will be exposed (FIG.  1 ). In the rotor mounting portions  25  and  35  are formed semi-circular peripheral (circumferential) rails  27  and  37 . The peripheral rails  27  and  37  are U-grooves. 
     In the upper and lower positions of the cover members  23  and  33 , recesses are formed as gear mounting portions  28 ,  29 ,  38  and  39  continuing to the outer periphery of the rotor mounting portions  25  and  35 . Furthermore, in the lower part of the cover member  33  is formed a threaded groove  40   a  constituting a screw hole  40  in which an output shaft  74  of a later-described motor  73  is screwed. 
     Next, FIG. 4 shows the state of the cover member of the above-described constitution in which the clamp rotor is mounted. The clamp rotor  63  shown in FIG. 1 which is mounted in the assembly of the cover members  23  and  24  and the cover members  33  and  34  is composed of a pair of semi-circular rotor pieces  61  and  62  as previously stated. On the periphery of the clamp rotor  63  are formed teeth, so that one gear is formed when the rotor pieces  61  and  62  are jointed. At the center of the clamp rotor  63  with the rotor pieces  61  and  62  jointed, that is, at the center of the contact surfaces  61   a  and  62   a  of the rotor pieces  61  and  62 , grasping portions  61   b  and  62   b  of a U-shaped portion are formed. The grasping portions  61   b  and  62   b  are formed so deep that two tubes, when grasped horizontally by the grasping portions  61   b  and  62   b , will be flattened to close in order to prevent the outflow of a liquid when cut. 
     On both sides of the rotor pieces  61  and  62  are formed peripheral projections  61   c  and  62   c  which fit in the peripheral rails  27 ,  27 ,  37  and  37  formed in the cover members  23 ,  24 ,  33  and  34 . 
     In the meantime, gears  64 ,  65 ,  66  and  67  are rotatably supported and mounted into mesh with the rotor pieces  61  and  62 , in the upper and lower positions, within the fixed clamp  21  and the movable clamp  31  of the first tube holder  1 . Of these gears  64 ,  65 ,  66  and  67 , the gear  64  mounted in the lower part of the cover members  23  and  24  which constitute the fixed clamp  21  functions as a drive gear coupled with the rotating axis of the driving motor. 
     The first tube holder  1  composed of the aforesaid component members is formed by mounting the rotor pieces  61  and  62  and the gears  64 ,  65 ,  66  and  67  to the cover members  23 ,  24 ,  33  and  34  of the fixed clamp  21  and the movable clamp  31 . Subsequently, with the projections  22  and  32  engaged with the rail grooves  11   a  of the base  11  of the fixed clamp  21  and the movable clamp  31 , the fixed clamp  21  is secured by fastening by screws the cover members  23  and  24 , and tie movable clamp  31  is slidably engaged in the rail groove  11   a.    
     Next, the second tube holder  2  will be explained. FIG. 5 is a perspective illustration showing the second tube holder  2 . 
     The fixed clamp  41  and the movable clamp  51  which constitute the second tube holder  2  comprise a block formed by jointing the cover members  43  and  44  and the cover members  53  and  54  similarly to the first tube holder  1 . The second tube holder  2 , however, is not provided with a rotating mechanism as seen in the first tube holder  1 . The cover members  43  and  44  and the cover members  53  and  54  have a mutually symmetrical shape. The shape is such that the projections  42  and  52  are formed on the bottom end of a plate of specific thickness; on the contact surface are formed grasping portions  45  and  55  to the same depth as the grasping portions  61   b  and  62   b  formed in the rotor pieces  61  and  62 . That is, the grasping portions  45  and  55  are formed to the depth that two tubes, when grasped end to end, will be flattened. 
     The meeting ends of the grasping portions  61   b  and  62   b  and the grasping portions  45  and  55  are formed shallower, so that the tubes will be cut and connected in the as-flattened state in the midpoint, that is, in the cutting position, between the first tube holder  1  and the second tube holder  2 . In the lower joint surface of the cover member  53  and.  54  is formed a screw hole  56  into which a later-described output shaft  76  of a motor  75  shown in FIG. 6 will be inserted. 
     The fixed clamp  41  and the movable clamp  51  consisting of the cover members  43  and  44  and the cover members  53  and  54  are constituted as follows: with the cover members  43  and  44  and the cover members  53  and  54  jointed, and with the projections  42  and  52  engaged with the rail grooves  12   a  of the base  12 , the fixed clamp  41  is fixedly secured by fastening the cover members  43  and  44  by screws, while the movable clamp  51  is slidably engaged with the rail groove  12   a.    
     The first tube holder  1  and the second tube holder  2  of the above-described constitution are mounted on the unillustrated body of the apparatus together with the driving means. Between the first tube holder  1  and the second tube holder  2 , as described later, the cutting means is vertically movably mounted, and is engaged with a motor for giving the turning effort to the aforesaid drive gear  64 , a motor for moving the movable clamps  31  and  51 , and a motor for moving the second tube holder  2  towards the first tube holder  1  side. FIG. 6 is a perspective illustration showing driving means for driving the first tube holder  1  and the second tube holder  2 . 
     In the driving means a motor  71  for transmitting rotation to the clamp rotor  63  is first connected to the drive gear  64  through a rotating axis  72 . Also mounted are motors  73  and  75  for moving the movable clamps  31  and  51  towards the fixed clamps  21  and  41 . The motors  73  and  75  have a screw portion on the rotating shafts thereof, and the screw portion is screwed into the screw holes  40  and  56  formed in the movable clamps  31  and  51 . Furthermore, there is mounted a motor  77  for moving the second tube holder  2  for a very short distance towards the first tube holder  1  side. On the rotating axis  78  of the motor  77  is also formed a screw portion which is screwed into an unillustrated screw hole formed in the base  12 . 
     The very short distance stated above for moving the second tube holder  2  is a distance for pressing to connect the melted ends of the tubes. The base  12  is mounted on an unillustrated rail and movably constituted as described above. 
     The motors  71 ,  73 ,  75  and  77  may be electric motors in general use, but it is preferable to use stepping motors which perform excellent positioning operation. 
     Next, a cutting plate  81  is a self-heating type heating-cutting plate shown in FIG.  9 . The cutting plate  81 , though not shown in detail, is formed by folding a metal plate, for example a copper plate, into two, and forming a heating resistor of a desired pattern through an insulating layer on the inside surface thereof, and exposing terminals at both ends of the resistor out of an opening formed in one end of the metal plate. The cutting plate  81  is held on a cutting plate holding member  82  which vertically reciprocates. The cutting plate holding member  82  is made of a heat-resisting ceramic material or resin, and is driven by a cylinder  83  and others shown in FIG.  7 . Furthermore, the cutting plate  81  is replaced every cutting operation with a new cutting plate  81  fed out of the cutting plate cassette by feeding means  84  shown in FIG.  7 . 
     Next, the control unit for controlling the tube connecting apparatus of the present embodiment will be explained. FIG. 7 is a block diagram showing the control unit. The control unit  95  has an engine controller  96 , a CPU  97 , a ROM  98 , and a RAM  99 , and carries out signal processing in accordance with a driving program stored in the ROM  98  while making use of the function of temporary storage of the RAM  99 . 
     In this control unit  95  the engine controller  96  is connected to the motors  71 ,  73 ,  75 ,  76 , the cylinder  83 , and the feeding means  84  through the driving circuits  71 A,  73 A,  75 A,  76 A,  83 A and  84 A. A driving signal is outputted from the engine controller  96  to the driving circuits  71 A,  73 A,  75 A,  76 A,  83 A and  84 A, to thereby control the driving of the motor  71 ,  73 ,  75 ,  76 , the cylinder  83 , and the feeding means  84  as described later. 
     The tube connecting apparatus of the present embodiment constituted as described above is designed to cut two flexible tubes made of a flexible resin such as flexible polyvinyl chloride, and then to connect the cut ends of these tubes. For instance when a peritoneopathy patient needs a peritoneum dialysis, as heretofore described, the present apparatus is used. The function of the present apparatus, therefore, will be concretely explained by referring to FIGS. 8 to  13 . The driving means including the motors  71 ,  73 ,  75  and  77  is not illustrated in the drawings. 
     First, as shown in FIG. 8, the fixed clamps  21  and  41  and the movable clamps  31  and  51  of the first tube holder  1  and the second tube holder  2  are in separated positions. In this state, the user sets two tubes  91  and  92  in these clamps. To describe concretely, between the grasping portions  61   b  and  62   b  formed in the rotor pieces  61  and  62  in the first tube holder  1  and between the grasping portions  45  and  55  of the second tube holder  2  located at the same level as the first tube holder  1 , tubes  91  and  92  are parallelly arranged. 
     After the setting of the tubes  91  and  92  on the apparatus, the switch provided on the unillustrated body of the apparatus is depressed to ON. In the present apparatus, the user performs only taking out this tube setting and tube removal after connection. Tube grasping and connecting operations are performed automatically by the control means  95 . 
     First, when the motors  73  and  75  are started, the turning effort is transmitted from the motors  73  and  75  to the movable clamps  31  and  51  through the rotating axes  74  and  76 . That is, the rotating axes  74  and  76  screwed in the screw holes  40  and  56  of the movable clamps  31  and  51  rotate to move the movable clamps  31  and  51  towards the fixed clamps  21  and  41 . Then, when the movable clamps  31  and  51  have come into contact with the fixed clamps  21  and  41  as shown in FIG. 9, the motors  73  and  75  stop turning, and accordingly the movable clamps  31  and  51  also stop moving. At this time, the tubes  91  and  92  placed between the grasping portions  61   b  and  62   b  and the grasping portions  45  and  55  are squeezed to close, becoming flattened in cross section. Therefore, liquid leakage from the tubes  91  and  92  will be prevented at the grasping portions  61   b  and  62   b  and the grasping portions  45  and  55 . 
     After the tubes  91  and  92  are squeezed to close by the grasping portions  61   b  and  62   b  and the grasping portions  45  and  55 , the cutting plate  81  disposed between the first tube holder  1  and the second tube holder  2  is moved upwardly by the cylinder  83  towards the tubes  91  and  92 . Then, as shown in FIG. 11, the cutting plate  81  cuts the tubes  91  and  92  vertically in the cutting position between the grasping portions  61   b  and  62   b  and the grasping portions  45  and  55 . That is, when the electric voltage is applied to the cutting plate  81  newly mounted on the cutting plate holding member  82  attached by the feeding means  84 , the heating temperature rises to 300 to 350° C. Then, the cutting plate  81  goes upwards to cross the tubes  91  and  92 , thus melting to cut these tubes  91  and  92 . 
     The cutting plate  81  will stop at a position shown in FIG. 11 where the tubes  91  and  92  have been cut. Subsequently the motor  71  is driven to turn the drive gear  64  by the rotating effort from the motor through the rotating axis  72 . The rotation of the drive gear  64  is transmitted to the clamp rotor  63  which is in mesh with the drive gear  64 . The motor  71  is driven until the clamp rotor  63  turns through 180 degrees. 
     Subsequently, as the clamp rotor  63  turns 180 degrees, the rotor pieces  61  and  62  are mutually translocated, within the fixed clamp  21  and the movable clamp  31 , so that, as shown in FIG. 12, the cut ends of the tubes  91   a  and  92   a  grasped in the first tube holder  1  turn 180 degrees along the side surface of the cutting plate  81 , thus changing positions. Therefore, as shown in FIG. 13, the cut end of the tube  91   a  will face the cut end of the tube  92   b  and the cut end of the tube  92   a  will face the cut end of the tube  91   b  respectively across the cutting plate  81 . In this position, the clamp rotor  63  will be locked from easily turning by an unillustrated locking mechanism, for instance a toothed hook. 
     The cut ends of the tubes  91  and  92  are hot in a condition of melted or softened resin, and therefore are in contact in an airtight manner with the cutting plate  81 . Therefore the cut ends of the tubes  91  and  92  turn along the side surface of the cutting plate  81  in this airtight condition, thus preventing the interior of the tubes  91  and  92  from being exposed to the atmosphere and maintaining the tubes in an aseptic condition. 
     Then, upon the downward retreat of cutting plate  81 , the second tube holder  2  is moved to the first tube holder  1 . That is, when the motor  77  is driven, the output of the motor is transmitted to the base  12  through the rotating axis  78 , thereby moving the base  12  for a very short distance towards the first tube holder  1  by the rotation of the rotating axis  78  which is screwed into the screw hole of the base  12 . This is for moving the tubes by the same amount as the cutting thickness (the thickness of the cutting plate  81 ) and squeezing the tube ends. Thus the cut ends of the tubes  91   b  and  92   b  and the tubes  92   a  and  91   a  will be melted and connected, forming two tubes  93  and  94  alternately translocated as shown in FIG.  14 . 
     Thereafter the motors  73  and  75  turn reversely, transmitting the rotational output to the movable clamps  31  and  51  through the rotating axes  74  and  76 . That is, the rotating axes  74  and  76  screwed in the screw holes  40  and  56  of the movable clamps  31  and  51  rotate to move the movable clamps  31  and  51  backwards as shown in FIG.  14 . At the same time, the motor  77  turns reversely to transmit the rotational output to the base  12  through the rotating axis  78 . The base  12  also moves backwards. 
     The user then takes out the tubes  93  and  94  thus released, from between the fixed clamps  21  and  41  and the movable clamps  31  and  51  separated. 
     According to the tube connecting apparatus of the first embodiment described above, since it has become possible to realize the automatization of all operations including tube holding, cutting and connection, the tube connecting apparatus is easy to handle even to a physically disabled person. That is, because of the adoption of the clamp rotor  63  provided with the grasping portions  61   b  and  62   b , the movable clamps  31  and  51  and the clamp rotor  63  can be operated independently, thus enabling automatization of a series of operations and accordingly reducing the time required for tube connection. 
     Also because the clamp rotor  63  in the fixed clamp  21  and the movable clamp  31  rotates, there is no disadvantage such as interference of the driving means with the tubes  91  and  92 . 
     Furthermore, because the tubes  91  and  92  are parallelly arranged between the fixed clamps  21  and  41  and the movable clamps  31  and  51 , such a disadvantage as the entanglement of the connected tubes at the time of removal has been obviated. 
     Next, the second embodiment of the present invention will be explained. 
     FIG. 15 is an external perspective illustration viewing from below the clamp section of the tube connecting apparatus of the present embodiment. The clamp section for grasping tubes comprises the first tube holder  101  and the second tube holder  102 , which are engagedly mounted on the body of the apparatus. On the first tube holder  101  and the second tube holder  102 , the movable clamps  121  and  141  which can be moved into contact with, and away from, the fixed clamps  111  and  131 . That is, the fixed clamps  111  and  131  are fixedly mounted on the body of the apparatus, and in the meantime the movable clamps  121  and  141  are vertically slidably mounted to form the clamp section. 
     The clamp section of the tube connecting apparatus has a rotating mechanism in the first tube holder  101 ; the second tube holder  102  is not provided with a rotating mechanism. Here, FIG. 16 is an external perspective illustration showing the fixed clamps  111  and  131  of the first tube holder  101  and the second tube holder  102 . FIG. 17 shows the fixed clamp  111  of the first tube holder  101 . The fixed clamps  111  and  131  and the movable clamps  121  and  141  are vertically symmetrical, and therefore only the fixed clamps  111  and  131  are shown. The constitution of the movable clamps  121  and  141  is indicated in parentheses. 
     First, therefore, the first tube holder  101  having the rotating mechanism will be explained. As seen from FIG. 15, both the fixed clamp  111  and the movable clamp  121  is formed by attaching covers  113  and  123  to the blocks  112  and  122  in which the rotor is mounted. Furthermore, as shown in FIG. 16, in the block  112  ( 122 ) is formed a rotor mounting section  114  ( 124 ) in which a semi-circular recess is provided. In this rotor mounting section  114  a clamp rotor  153  is mounted in either of a pair of semi-circular rotor pieces  151  and  152  constituting the holder. 
     As shown in FIG. 17, a semi-circular cutout  114   a  ( 124   a ) is formed in the central part of the rotor mounting section  114  ( 124 ). Also, in the rotor mounting section  114  ( 124 ) a peripheral rail  114   b  ( 124   b ) is formed. The peripheral rail  114   b  ( 124   b ) is a projecting rail formed in a semi-circular shape. The block  112  is provided (the block  122  is not provided) with the gear mounting section  115  formed continuing to the rotor mounting section  114 . Furthermore, the blocks  112  and  122  are provided with guide holes  116   a  and  116   b  ( 126   a  and  126   b ) through which two guide shafts are vertically mounted. 
     In the meantime, in the cover  113  ( 123 ) are formed semi-circular cutout  117   a  ( 127   a ) and a semi-circular peripheral rail  117   b  ( 127   b ) correspondingly to the blocks  112  and  122 . The cover  113  is provided (the cover  123  is not provided) with a through hole  118  through which a rotating axis  154   a  of a later-described drive gear  154  is mounted as shown in FIG.  15 . 
     Next, FIG. 18 shows blocks  112  and  122  of the first tube holder  101  mounted with a clamp rotor  153 . The clamp rotor  153  mounted in the blocks  112  and  122  consists of a pair of semi-circular rotor pieces  151  and  152 , is provided with teeth formed on the periphery thereof, and is so constituted as to make one gear when both rotor pieces  151  and  152  come in contact with each other. 
     In the gear mounting section  115  there is rotatably mounted the drive gear  154  which is in mesh with the rotor pieces  151  and  152  and directly coupled with the rotating axis of the driving motor. 
     At the center of the clamp rotor  153 , that is, at the center of the contact surfaces of the rotor pieces  151  and  152 , U-grooves  151   b  and  152   b  are formed deep enough to allow the insertion of one tube as shown in FIG. 16; and formed at the end of the grooves are grasping portions  151   a  and  152   a  which protrude on the opposite side of the second tube holder  102  to squeeze and grasp the tubes. The grasping portions  151   a  and  152   a  are formed so high as to hold flattened ends of two tubes when the two tubes are set one on top of the other and squeezed. This is for closing the cut ends of the tubes in order to prevent fluid leakage from the tubes. 
     Next, in the second tube holder  102 , as shown in FIG. 16, both clamps  131  ( 141 ) are provided with drilled guide holes  132   a  and  132   b  ( 142   a  and  142   b ) which are vertically guided along two guide shafts; and a grasping portion  133   a  ( 143   a ) is formed projecting to the first tube holder  101  side. A U-groove  133   b  ( 143   b ) similar to those formed in the rotor pieces  151  and  152  and deep enough to insert one tube therein is formed projecting to the first tube holder  101  side. At the end thereof a grasping portion  133   a  ( 143   a ) is formed. 
     Next, FIG. 22 is a block diagram showing the control unit of the tube connecting apparatus. Between the first tube holder  101  and the second tube holder  102  there is vertically movably disposed the cutting plate  105  which is tube cutting means as described later, and is coupled with a motor  155  for giving a turning effort to the aforementioned drive gear  154 , motors  156  and  157  for moving the movable clamps  121  and  141 , and a motor  158  for moving the second tube holder  102  towards the first tube holder  101 . 
     To the driving means, first the motor  155  for transmitting rotation to the clamp rotor  153  is connected to the drive gear  154  through the rotating axis  154   a . Furthermore, there are mounted motors  156  and  157  for moving the movable clamps  121  and  141  into contact with, and away from, the fixed clamps  111  and  131  respectively. To move the movable clamps  121  and  141  into contact with, and away from, the fixed clamps  111  and  131 , it is conceivable to adopt such a constitution that an eccentric cam in contact with the movable clamps  121  and  141  is mounted on the rotating axes of the motors  156  and  157 . 
     Furthermore, the motor  158  is mounted for moving the second tube holder  102  for a very short distance towards the first tube holder  101 . In this case also, there may be mounted an eccentric cam on the rotating axis of the motor  158  to slide the second tube holder  102  for a very short distance towards the first tube holder  101  side. The above-mentioned very short distance for moving the second tube holder  102  is meant by a distance necessary for squeezing to connect the melted ends of tubes. 
     The motors  156 ,  157 ,  158  and  178  may be motors in general, but are preferably stepping motors which have an excellent positioning function. 
     In the meantime, tubes are carried by a support  171  to between the fixed clamps  111  and  131  and the movable clamps  121  and  141  thus disposed, particularly, one on top of the other in the holding position in the upper and lower U-grooves  151   b  and  152   b  where the grasping sections  151   a ,  152   a ,  133   a  and  143   a  are formed. 
     The support  171  is constituted such that the tubes  103  and  104  will be carried to the holding position from outside of the space of movement where the movable clamps  121  and  141  are vertically arranged. That is, this constitution is a part featuring the present invention, which has solved the aforesaid problems of conventional tube connecting apparatus. Hereafter, therefore, the support  171  will be explained in detail. 
     FIG. 19 is an external perspective view showing the support  171 . A body  172  of the support  171  is formed of a U-shaped square member, on both ends of which the holders  173  and  174  are engaged. The holders  173  and  174  are both formed such that the U-grooves  173   a  and  174   a  are aligned in the same direction. 
     The width of the U-groove  174   a  of the holder  174  present on the second tube holder  102  side is nearly the same as the outside diameter of the tubes  103  and  104 , while the width of the U-groove  173   a  of the holder  173  on the first tube holder  101  side is formed nearly twice as large as the outside diameter of the tubes  103  and  104 . This is because the tubes  103  and  104  are firmly supported by the holder  174 , and for the purpose of preventing the tubes  103  and  104  turned by the clamp rotor  153  in the holder  173  from being twisted in the grooves. 
     On the holders  173  and  174  are formed projections  173   b  and  174   b  which fit in rail grooves formed in the body  172  and supported in the illustrated state by springs  179 ,  179  inserted in the body  172 ; and furthermore a sliding mechanism is provided to slide the projections up and down. 
     FIGS. 20 and 21 are side views of the feed mechanism of the support  171 . FIGS. 20 and 21 show the operating condition, which will be described later. 
     In the support  171  a feed screw  175  which is rotatably engaged with an internal screw  176   a  (FIG. 19) formed in the body  172 . Then, the gear  177   a  secured on the feed screw  175  and a gear  177   b  secured on the output shaft of the motor  178  are engaged to transmit the motor power. 
     In the meantime, a guide hole  176   b  is provided (FIG. 19) in parallel with the internal screw  176   a  in the body  172  of the support  171 , and the guide shaft provided in the body of the apparatus is inserted through, thus functioning to stop rotation. 
     In the meantime, the cutting plate  105  for cutting tubes is a self-heating type heating-cutting plate. The cutting plate  105  is made by folding a metal plate, such as a copper plate, into two, forming a heating resistor of a desired pattern through an insulating layer on the inner surface, and exposing terminals on both ends of the resistor out of an opening formed in one end of the metal plate. 
     The cutting plate  105  is held by the cutting plate holding member which reciprocates up and down. The cutting plate holding member is produced of a heat-resisting ceramic or resin material, and connected to the cylinder  196  (FIG. 22) for positioning. Also, the cutting plate  105  is replaced every operation with a new cutting plate  105  which is fed out one by one from the cutting plate cassette. 
     Next, a control unit for controlling the tube connecting apparatus of the second embodiment will be explained. FIG. 22 is a block diagram showing the control part of the tube connecting apparatus. A control unit  100  has an engine controller  195 , a CPU  197 , a ROM  198 , and a RAM  199 , and carries out signal processing in accordance with a driving program stored in the ROM  198  while making use of the function of temporary storage of the RAM  199 . 
     In this control unit  100  the engine controller  195  is connected to the motors  155 ,  156 ,  157 ,  158  and  178 , through the driving circuits  155 A,  156 A,  157 A,  158 A and  178 A. A driving signal is outputted from the engine controller  195  to the driving circuits  155 A,  156 A,  157 A,  158 A and  178 A, to thereby control the driving of the later-described motors  155 ,  156 ,  157 ,  158  and  178 . The cylinder  196  also is connected to the engine controller  195  through the driving circuit  196 A. 
     Therefore, the tube connecting apparatus of the second embodiment performs cutting and connection of tubes by the following operation. 
     The user first sets tubes  103  and  104  one on top of the other in the support  171  as shown in FIG.  20 . At this time, the holders  73  and  174  in which the tubes  103  and  104  are set are disposed outside of the grasping area in which the movable clamps  121  and  141  move up and down, and therefore the user is required only to hold, by both hands, the tubes  103  and  104  in such a manner that the length of the portion of the tubes thus held is longer than the distance of the holders  173  and  174 , and then to slip the tubes down into the U-grooves  173   a  and  174   a . Subsequently to the insertion of the tubes  103  and  104 , the switch is depressed to accomplish the following operation of the tube connecting apparatus. With the operating switch depressed to ON, the tube connecting apparatus is controlled as described below in accordance with a preset program. 
     First, the support  171  supporting the tubes  103  and  104  is moved to the holding position in which the tubes  103  and  104  will be clamped by the fixed clamps  111  and  131  and the movable clamps  121  and  141 . A motor  178  starts to transmit its turning effort to a feed screw  175  through gears  177   a  and  177   b . As the feed screw  175  rotates, there takes place a thrust at the support  171  being locked from rotation, thus moving the tubes  103  and  104  leftwards in FIG.  20 . From the motor  178  a specific amount of rotation is imparted and the tubes  103  and  104  being fed on the support  171  are carried as far as the holding position including the upper and lower U-grooves  151   b  and  152   b  ( 133   b  and  143   b ) in which the tubes will be positioned one on top of the other as shown in FIG.  21 . 
     Subsequently to the positioning of the tubes  103  and  104 , first the motors  156  and  157  start to transmit their turning effort to the movable clamps  121  and  141  through for instance the rotation of the eccentric camp as described above. Thus the movable clamps  121  and  141  in contact with the eccentric cam move toward the fixed clamps  121  and  141  side along the cam face of the eccentric cam. When the movable clamps  121  and  141  come into contact with the fixed clamps  111  and  131 , the motors  156  and  157  stop turning to stop the movement of the movable clamps  121  and  141 . At this time, the tubes  103  and  104  set between the grasping portions  151   a  and  152   a  and the grasping portions  133   a  and  143   a  are squeezed flat to close, thereby preventing liquid leakage when the tubes  103  and  104  are cut at the grasping portions  151   a  and  152   a  and the grasping portions  133   a  and  143   a.    
     The tubes  103  and  104  thus squeezed by the grasping portions  151   a  and  152   a  and the grasping portions  133   a  and  143   a  and held in the U-grooves  151   b ,  152   b ,  133   b  and  143   b  receive a load in one direction from the movable clamps  121  and  141  to the fixed clamps  111  and  131  side. The lower tube  104  is set on the tube  103  to receive an indirect load, while the tube  103  receives a local load from the grasping portions  152   a  and  143   a.    
     Therefore, variations will occur in the load distribution of the tubes  103  and  104 , and also in the sectional form. Particularly the amount of deformation of the tube  103  which directly receives the load from the grasping portions  143   a  and  152   a  increases great, resulting in a different sectional form from the tube  104 . 
     The above-described disadvantage, however, has been obviated by providing the holders  173  and  174  with the sliding mechanism. 
     First, of the tubes  103  and  104  positioned in the holding position by the support  171 , the tube  104  is at a higher level than the upper surface of the fixed clamp  111  as shown in FIG.  23 . Then, when the movable clamps  121  and  141  have gone down, the tubes  103  and  104 , being clamped, are also moved down, and therefore the holders  173  and  174  are loaded through the descending tubes  103  and  104 . Therefore, the holders  173  and  174 , receiving load from the tubes  103  and  104 , slide downwards against the force of the springs  179  as shown in FIG.  24 . 
     As the holders  173  and  174  go downwards, the tubes  103  and  104  also descend, lowering the entire contact surface of the tubes  103  and  104  to the level at which the tubes  103  and  104  are grasped (indicated by a dot line in FIG. 24) by the grasping portions  133   a  and  143   a  and the grasping portions  151   a  and  152   a . Thus the load being applied to the tubes  103  and  104  is balanced to uniformly compress the tubes flat. 
     After the tubes  103  and  104  are compressed to close by the grasping portions  133   a  and  143   a  and the grasping portions  151   a  and  152   a , the cutting plate  105  disposed between the first tube holder  101  and the second tube holder  102  is moved upwards by the cylinder  196  towards the tubes  103  and  104 . Then, as shown in FIG. 25, the cutting plate  105  vertically cuts the tubes  103  and  104  between the grasping portions  133   a  and  143   a  and the grasping portions  151   a  and  152   a . That is, the cutting plate  105  newly mounted on the cutting plate holding member by the feeding means, when applied with the electric voltage, rises in temperature to 300 to 350° C., thereby melting to cut the tubes  103  and  104  when rising across the tubes  103  and  104 . 
     The cutting plate  105  then stops at the position shown in FIG. 25 after cutting the tubes  103  and  104 , and subsequently the motor  155  is driven to rotate the drive gear  154  by the turning effort through the rotating axis  154   a . The rotation of the drive gear  154  is transmitted to the clamp rotor  153  which is in mesh with the drive gear  154 . The motor  155  turns until the clamp rotor  153  turns through 180 degrees. 
     Then, as the clamp rotor  153  turns through 180 degrees, the rotor pieces  151  and  152  change positions in relation to the fixed clamp  111  and the movable clamp  121 ; and as shown in FIG. 26, the cut ends of the cut tubes  103   a  and  104   a  grasped on the first tube holder  101  turn 180 degrees along the side surface of the cutting plate  105 , thus changing positions with each other. Accordingly, the cut portions, namely the cut ends of the tube  103   a  and the tube  104   b  and the cut ends of the tube  104   a  and the tube  103   b , face each other. In this position, the clamp rotor  153  is locked by a locking mechanism such as a toothed hook in order not to rotate easily. 
     Since the holder  173  has a widely formed U-groove  173   a , the tubes  103   a  and  104   a  held by the clamp rotor  153  rotate without being twisted. 
     The cut ends of the tubes  103  and  104  are hot with melted and softened resin, being in airtight contact with the cutting plate  105 . Therefore the cut ends of the tubes  103  and  104 , when rotating, rotate along the side surface of the cutting plate  105  while in airtight contact with the cutting plate  105 . The interior of the tubes  103  and  104  can be kept aseptic without exposure to the atmosphere. 
     Next, the cutting plate  105  is moved back downwards by a cylinder  196  and at the same time the second tube holder  102  is moved to the first tube holder  101 . That is, the motor  158  is driven to move the second tube holder  102  by an eccentric cam for a very short distance towards the first tube holder  101 . This is for pressing to connect tubes by moving the second tube holder  102  for a cutting width (thickness of the cutting plate  105 ). The tubes  103   b  and  104   b  and the tubes  104   a  and  103   a  are melted and connected to each other at the cut ends, thus forming two tubes  103 A and  104 A which have been mutually translocated as shown in FIG.  13 . 
     Thereafter the motors  156  and  157  turn further to withdraw the movable clamps  121  and  141 . At the same time the motor  158  also turns further to withdraw the second tube holder  102 . 
     Then, when the movable clamps  121  and  141  move away from the fixed clamps  111  and  131 , the motor  178  turns reversely, thus turning the feed screw  175  to move the support  171  backwards. Therefore the support  171  holding the connected tubes  103 A and  104 B shown in FIG. 20 is moved back to the initial position shown in FIG. 6, where the user takes out the tubes  103 A and  104 B. 
     The tube connecting apparatus of the second embodiment has heretofore been explained. According to the present apparatus, the user is required only to insert the tubes  103  and  104  into the holders  173  and  174  of the support  171 . It, therefore, becomes unnecessary to move the tubes  103  and  104  to between the fixed clamps  111  and  131  and the movable clamps  121  and  141  and to position the tubes in the holding portion, allowing easier handling of tube mounting. 
     Particularly, the holders  173  and  174  of the support  171 , being disposed outside of the first tube holder  101  and the second tube holder  102 , can be inserted very easily without interference when the tubes  103  and  104  are inserted. 
     In the holders  173  and  174  are formed U-grooves  173   a  and  174   a , into which the tubes  103  and  104  can be just slipped down. The user, therefore, needs no special effort, and can handle the apparatus with ease. 
     Also, as previously stated, the holders  173  and  174  supporting the tubes  103  and  104  receive a reaction force of the tubes with respect to the body  172 , or slide with the operating power of the clamp, thereby balancing the load applied to the tubes  103  and  104  at the time of grasping, flattening the tubes  103  and  104  to a uniform sectional form of their cut ends, and accordingly enabling mutual translocation and proper connection of the tubes. 
     One embodiment of the tube connecting apparatus according to the present invention has heretofore been explained. It should be noticed that the present invention is not limited the aforementioned embodiment and various modifications are possible within the scope of the invention. 
     For example in the above-described embodiment a motor is used in driving means, but a solenoid and a cylinder may be used in place of the motor. 
     Also, for example in the above-described embodiment, the clamp rotor  63  is mounted only in the first tube holder  1 , but may be mounted also in the second tube holder  2  and mutually rotated. 
     Furthermore, for example in the above-described embodiment, two tubes are connected. The number of tubes to be connected, however, may be increased to three or more. 
     For example in the above-described embodiment, the movable clamps  31  and  51  are designed to contact the fixed clamps  21  and  41 , but both the movable and fixed clamps may be movable. 
     In the above embodiment, the rotating power of the motor  178  is transmitted through the feed screw  175  to the support  171 . An eccentric cam may be used instead for the feed screw. 
     According to the present invention, therefore, each of the first tube holder and the second tube holder is provided with a pair of clamps having a holding portion for holding a plurality of tubes. The pair of clamps can be moved into contact with, and away from, each other to grasp the tubes. The holding portion of one or both of the first tube holder and the second tube holder is rotatably disposed in the circumferential direction of the tubes thus grasped, and is provided with grasping means for moving into contact with, and away from, the pair of clamps of the first tube holder and the second tube holder, and rotating means for rotating one or both of the holding portions of the first tube holder and the second tube holder. It, therefore, has become possible to provide a tube connecting apparatus which the user can easily handle with reduced load and without interference between the driving means and the tubes. 
     Furthermore, according to the present invention, the holding portion for grasping the tubes comprises a pair of semi-circular clamp rotors rotatably mounted in a common circumferential grooves provided in a pair of clamps, and there is formed a cutout groove in the central part of the pair of clamp rotors in contact with each other. It is, therefore, unnecessary to take the provision of a space for rotation into account, and it has become possible to provide the tube connecting apparatus presenting no interference with other members. 
     Furthermore, according to the present invention, teeth are formed on the circumference of the clamp rotor which is the holding portion and are engaged with the drive gear in the clamp coupled with a motor which is rotating means; it, therefore, is possible to provide a tube connecting apparatus in which the driving means will not interfere with tubes. 
     Furthermore, according to the present invention, one of the pair of clamps is secured on a rail, while the other clamp is mounted movable on the rail by the grasping means. It is, therefore, has become possible to provide a tube connecting apparatus capable of reliably grasping tubes by moving on the rail. 
     Furthermore, according to the present invention, a preferable device can be selected from among motor, solenoid, and cylinder for the grasping means, thereby enabling to realize proper operation and cost reduction of the tube connecting apparatus. 
     Furthermore, according to the present invention, when the switch is operated, the control means drives the grasping means to move a pair of clamps of the first tube holder and the second tube holder, and after the clamps have come into contact with each other, the moving means is driven to move the cutting means to heat and melt the tubes. Subsequently, after the tube is cut by cutting means, the rotating means is driven to rotate the holding portion grasping the tubes; and after the rotation of the rotating means, the adjusting means is driven simultaneously with the withdrawal of the cutting means, to thereby move the first tube holder and the second tube holder closer to each other. And then a pair of clamps of the first tube holder and the second tube holder which are in contact with each other are away from by the grasping means. The user, therefore, can easily handle the apparatus with less burden. Also it is possible to provide a tube connecting apparatus in which no interference occurs between the driving means and the tubes. 
     According to the present invention, one or both of the holding portions of the first tube holder and the second tube holder are separated into rotatable members which have a rotation symmetry in relation to a center of a rotating axis. The tubes, after being cut by the cutting means, are turned for mutual translocation and connection. For tube positioning, there is provided supporting means which supports at least two tubes one over the other in the direction of movement of the holding portions and moves the tubes from outside of the grasping area of the holding portions to inside of said grasping area. Thus it has become possible to provide a tube connecting apparatus which facilitates tube mounting. 
     Furthermore, according to the present invention U-grooves are provided as a support of the supporting means, and therefore it has become possible to provide a tube connecting apparatus which enables the user to easily mount tubes only by slipping the tubes down into the grooves. 
     Furthermore, according to the present invention, the first tube holder and the second tube holder are disposed between the supports of the supporting means; the width of the U-groove of one support is nearly the same as the outside diameter of the tube, while the width of the U-groove of the other support is twice as large as the outside diameter of the tube. It, therefore, has become possible to provide a tube connecting apparatus which reliably holds the tubes in position on one side while allowing smooth rotation of the tubes on the other side without distortion and excessive force application. 
     Furthermore, according to the present invention, it has become possible to provide a tube connecting apparatus in which a sliding mechanism which changes positions when the support of the supporting means has receiving a load; and therefore uneven load on the upper and lower tubes can be balanced, thereby ensuring uniformly compressing tube ends into a flat form. 
     Furthermore, according to the present invention, it has become possible to provide a tube connecting apparatus which facilitates tube mounting. That is, transporting means for moving the supporting means determines the position of the support between two points of the tube mounting position outside of the grasping area of the holding portions and the holding position located within the grasping area; and therefore the user is required only to mount the tubes in the supports. 
     Furthermore, according to the present invention, it has become possible to provide a tube connecting apparatus in which since a motor, a solenoid, or a cylinder is selected as the transporting means, the most suitable driving source can be adopted with assembly with other mechanisms and cost taken into account.