Abstract:
A device for individually packaging medication comprises: a conveyance member for conveying a long packaging sheet, said packaging sheet being folded in two along the longitudinal direction thereof with a fold line disposed on the lower side; and a sealing member for sealing the packaging sheet. The sealing member is configured by integrating longitudinal and lateral sealing units. The longitudinal sealing unit being adapted to seal the edge of the packaging sheet, located on an opposite side of the fold line, and the lateral sealing unit being adapted to seal the packaging sheet at predetermined intervals in the longitudinal direction. The device further comprises: a support member for supporting the sealing member; and a control unit causing the sealing member to rotate idle while separating the longitudinal sealing unit from the packaging sheet and thereafter causing said longitudinal sealing unit to come into contact again with said packaging sheet.

Description:
[0001]    This application is a national phase application under 35 U.S.C. §371 of International Application Serial No. PCT/JP2011/062893, filed on Jun. 6, 2011, and claims the priority under 35 U.S.C. §119 to Japan Patent Application No. 2010-132143, filed on Jun. 9, 2010 and Japan Patent Application No. 2011-021963, filed on Feb. 3, 2011, which are hereby expressly incorporated by reference in their entirety for all purposes. 
       TECHNICAL FIELD 
       [0002]    This invention relates to a medicine packing apparatus for packaging medications such as tablets including capsules and powder. 
       BACKGROUND OF THE INVENTION 
       [0003]    A variety of medicine packing apparatus are available for individually packaging each dose (single packet) of medications such as tablets or powders as per prescription, and for producing the packaged medicines continuously. Among them is a device using rolls wherein a long and narrow packaging sheet is pre-folded in two in the length direction. Generally, in the packaging unit of this type of medicine packing apparatus, the packaging sheet is fed from the roll, and following printing of necessary information with a printer, the packaging sheet is opened from the folded state, and a single dosage of medication is injected from the nozzle of a hopper inserted in this opening. Subsequently, the packaging sheet is sealed (heat sealed) in a heat sealing section so as to seal the medication. 
         [0004]    For example, Patent document 1 discloses a medicine packing apparatus in which a pair of first rotating shafts is provided in a direction (hereafter referred to as transverse direction) perpendicular to the conveying direction of the packaging sheet, a transverse sealer for sealing the packaging sheet in transverse direction is provided in this pair of first rotating shafts, a second rotating shaft is provided coaxially with each first rotating shaft, and a longitudinal sealer for sealing the packaging sheet in the conveying direction (hereinafter referred to as vertical direction) is provided in this second rotating shaft so that sealing of the packages can be done at once. In this medicine packing apparatus, it is possible to adjust the size of the sachet as per the supply amount of medication by controlling the drive of the second rotating shaft provided with the longitudinal sealer, and adjusting a conveyance rate of the packaging sheet, for example, by varying a conveyance speed. 
         [0005]    However, in the medicine packing apparatus disclosed in Patent document 1: Japanese Patent Publication No. 2942769, a heater is housed in the first rotating shaft, heat from this heater is conveyed to the transverse sealer of the first rotating shaft, and further conveyed from the first rotating shaft to the longitudinal sealer of the second rotating shaft, and therefore, there was a drawback of a large temperature difference between the transverse sealer and longitudinal sealer. There was also an issue such that, because the intervals at which the longitudinal sealer contacts the packaging sheet and the intervals at which the transverse sealer contacts the packaging sheet were different, the timings of heat transferred from the respective sheet sections to the packaging sheet were different, and a temperature difference between the transverse sealer and longitudinal sealer becomes all the more larger. Accordingly, it was necessary to use an expensive packaging sheet wherein a difference between the fusion temperature and heat resistance temperature is large, resulting in an increase in cost of the packaging sheet. In addition, there was also a drawback of the structure becoming complicated because the first rotating shaft provided with a heat sealing part and the second rotating shaft provided with a longitudinal sealer were driven by separate drive mechanisms. 
       SUMMARY OF THE INVENTION 
       [0006]    The medicine packaging apparatus of the present invention, which is provided to solve the above-mentioned problems, has an objective of reducing the manufacturing cost of a packaging sheet by reducing a temperature difference between transverse sealer and longitudinal sealer, as well as to simplify the structure of the sealers and adjust the size of the dose sachet according to the supply quantity of medicine. 
         [0007]    In order to solve the above-mentioned problems, the present invention provides a medicine packing apparatus, including 
         [0008]    a conveyance member to convey a long packaging sheet with the sheet folded in two along the length direction and the fold line being positioned downwardly, 
         [0009]    a medicine supplier to feed medicine from top onto the packaging sheet conveyed by the conveyance member, and 
         [0010]    a pair of sealers that can hold the conveyed packaging sheet from both sides and heat-seal the sheet while rotating, and pack the supplied medicine by one package each, wherein 
         [0011]    the sealers have a configuration wherein the longitudinal sealer that seals the edge part, which is opposite to the fold line of the packaging sheet, in the conveying direction, and a transverse sealer that seals the packaging sheet in a direction orthogonal to the conveying direction at a predetermined interval in the conveying direction are integrated, and 
         [0012]    a support member that supports the pair of sealers such that at least one of the sealers is movable so as to come in contact with or move away from the packaging sheet, and 
         [0013]    a controller that moves the sealers, and adjusts the sealing position sealed by a transverse sealer in the length direction by rotating at least the longitudinal sealer at a position retracted from the said packaging sheet, 
         [0000]    are provided. 
         [0014]    In the above configuration, with a simple configuration of just moving a sealer to a retracted position and rotating it, it is possible to change the sealing interval by the transverse sealer in a direction orthogonal to the conveying direction (transverse direction). 
         [0015]    By integrating the longitudinal sealer and the transverse sealer, it becomes possible to eliminate the temperature difference between the sealers and to seal a packaging sheet at a desired temperature. Therefore, because a packaging sheet made of a cheaper material where a difference between fusion temperature and heat resistance temperature is small can be used, it becomes possible to reduce the manufacturing cost of a packaging sheet. 
         [0016]    In addition, because of an integration of the sealers, it becomes possible to drive the sealers with a single drive mechanism, and therefore, the structure of the sealers can be simplified, and the sealing interval of the packaging sheet by the transverse sealer can be adjusted according to the supply quantity of a medicine. 
         [0017]    With the help of the support member, it is possible to support at least one sealer such that it can move via both ends, or to support the sealer such that it can rotate around one end, and rotation is possible via the other end of the sealer. 
         [0018]    It is preferable that, when adjusting the sealing positions by the transverse sealer, the controller sets the rotational direction in the retracted position of the sealer as a direction wherein the amount of rotation required for rotating the transverse sealer to a desired location is small. 
         [0019]    With this configuration, the interval of sealing a packaging sheet by a transverse sealer can be quickly changed. 
         [0020]    It is preferable that the controller stop the packaging sheet when moving away the longitudinal sealer. 
         [0021]    With this configuration, it is possible to do away with unnecessary and wasteful drive. 
         [0022]    It is preferable that the controller maintain the conveyance of the packaging sheet when moving the longitudinal sealer away from the sheet, and the range in which the packaging sheet is conveyed before attaching the longitudinal sealer to the packaging sheet again be in an area where vertical sealing is possible. 
         [0023]    With this configuration, it is possible to continue the sealing operation and to achieve an efficient process without stopping the conveyance of the packaging sheet. 
         [0024]    In order to make the range of conveying the packaging sheet to be in a region where vertical sealing can be performed, the controller may make the conveyance speed of the packaging sheet slower than at the time sealing when the longitudinal sealer is moved away from the sheet. 
         [0025]    With the above-mentioned controller, in order to set the range of conveying the packaging sheet to be in the region where vertical sealing can be performed, when moving away the longitudinal sealer, the conveyance speed of the packaging sheet may be made slower than that at the time of sealing, or the sealer may be allowed to idle at a higher speed than that at the time of sealing. 
         [0026]    It is preferable that the sealers are provided movably in the conveying direction of the packaging sheet, and the controller makes the sealer move from its initial position in the conveying direction of the packaging sheet after the longitudinal sealer is detached from the packaging sheet and before the sealer contacts the sheet again, and after the longitudinal sealer contacts the sheet, the controller makes the sealer return to the original position, rotating at a speed faster than at the time of sealing. 
         [0027]    With the above configuration, even if the sealer is made to idle after the longitudinal sealer is moved away from the packaging sheet and again contacted with the packaging sheet, a gap is not formed in the region sealed by the longitudinal sealer. With this, it is possible to change the sealing interval in the transverse direction while reliably sealing the packaging sheet in the vertical direction. 
         [0028]    It is preferable that the support member be provided with a moving mechanism to move at least one sealer to a sealing position where the longitudinal sealer is in close contact with the packaging sheet, and to a retracted position where it is moved away from the sheet. 
         [0029]    Accordingly, in spite of a simple and inexpensive configuration of moving only the heat roller, it becomes possible to easily move the heat roller away from the packaging sheet, and easily change the rotating position of the transverse sealer with respect to the packaging sheet. 
         [0030]    It is further possible to make the sealer rotate around one end, wherein the moving mechanism presses the other end of the one sealer to rotate it from the sealing position to the retracted position. 
         [0031]    It is preferable that each of the sealers have a long cylindrical shape formed as one body from the same material. 
         [0032]    With this configuration, it becomes possible to conduct heat uniformly, to make the portions heated by the sealers in an uniform temperature, and to appropriately seal the packaging sheet uniformly. 
         [0033]    It is preferable that the above-mentioned pair of sealers is configured from a fixed heat roller, and a movable heat roller that is disposed parallel to the fixed heat roller and that rotates around one end to contact or move away from the fixed roller through the packaging sheet, and 
         [0034]    wherein the moving mechanism is provided with a motor for rotation, a connecting bar whose one end is rotatably connected in an eccentric position with respect to the rotating shaft of this motor for rotation, a moving piece connected rotatably at the other end of this connecting bar, and a pressing accepting member provided at the other end of the movable heat roller and that can be pressed by the moving piece. 
         [0035]    With this configuration, by driving the motor for rotation, the movable heat roller can be rotated through the connecting bar, the moving piece and the pressing accepting member. Because of the simple configuration in which the connecting bar, moving piece and operation receiving member are simply connected to each other in a rotatable manner, manufacturing can be done at a lower cost and operation failures are not likely to occur. 
         [0036]    It is preferable to provide a bias member to bias one sealer to other sealer, wherein the biasing force of the bias member can be adjusted. 
         [0037]    Accordingly, despite of the simple and low-cost configuration, it becomes possible to not only bias one sealer to the other sealer, but also to adjust the biasing force. 
         [0038]    It is preferable to provide a fixed block that rotatably holds one of the sealers, and 
         [0039]    a movable block that holds the other sealer rotatably and that is rotatably connected to the fixed block, wherein that the above-mentioned moving mechanism be attached to the end of the movable block. 
         [0040]    With this configuration, it becomes possible to effectively utilizing dead space to dispose the moving mechanism, and to prevent an increase in the overall size of the apparatus. Further, even if the packaging sheet is jammed between the two sealers, the moving mechanism does not obstruct when rotating the movable block with respect to fixed block, and the packaging sheet can be easily removed. 
         [0041]    It is preferable to provide a bias member that biases one sealer towards the other sealer, 
         [0042]    wherein the moving mechanism moves the other sealer between the sealing position and retracted position. 
         [0043]    With this configuration, when one sealer is moved away from the other sealer, the biasing force of the bias member does not affect adversely, and the operation can be effected smoothly. Therefore, it becomes possible to manufacture the drive mechanism intended for detaching the sealers at a lower cost with a simple configuration. 
         [0044]    It is preferable to provide a stopper for preventing rotation by contacting with one of the sealers when the other sealer is rotated to a retracted position by the moving mechanism. 
         [0045]    With this configuration, even if one sealer is moved away from the other sealer, due to the action of the stopper, the one sealer will not advance into the conveyance path of the packaging sheet to cause an adverse effect. 
         [0046]    According to the present invention, the position sealed by the transverse sealer can be adjusted in the length direction by moving the sealers and rotating them with at least the longitudinal sealer in a retracted position of being detached from the packaging sheet, and therefore, despite of a simple configuration, the sealing interval by the transverse sealer in a direction (transverse direction) orthogonal to the conveying direction can be changed. Also, because the longitudinal sealer and the transverse sealer are integrated, a temperature difference between the sealers is eliminated, and a packaging sheet can be sealed at a desired temperature. Therefore, since a packaging sheet made of a cheaper material where a difference between fusion temperature and heat resistance temperature is small can be used, it becomes possible to reduce the manufacturing cost of packaging sheet. In addition, the structure of sealers can be simplified by integrating the sealers, and the sealing interval of the packaging sheet by the transverse sealer can be changed in accordance with the supply amount of medicine. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0047]    The present disclosure is described in conjunction with the appended figures: 
           [0048]      FIG. 1  is a perspective view of the exterior of a medicine packing apparatus according to the first embodiment seen from front. 
           [0049]      FIG. 2  is a front view of  FIG. 1 . 
           [0050]      FIG. 3  is a front view of the heat sealing part shown in  FIG. 2 . 
           [0051]      FIG. 4  is a cross-sectional view of the V-V line in  FIG. 3 . 
           [0052]      FIG. 5  is a front view of  FIG. 3  showing a state wherein the heat roller of movable block is away from the heat roller of the fixed block. 
           [0053]      FIG. 6  is a block diagram showing a state wherein the controller and various motors are connected. 
           [0054]      FIG. 7  is a flow chart for controlling the heat sealing portion of  FIG. 3 . 
           [0055]      FIG. 8  is a graph showing the timings of the rotation of heat roller and conveyance roller reducing the sealing interval of the transverse direction and opening/closing operation of the heat roller. 
           [0056]      FIG. 9  is a top view depicting a state of heat roller sealing a packaging sheet. 
           [0057]      FIG. 10  is a side view showing the operation of heat roller and conveyance roller in the section A of  FIG. 8 . 
           [0058]      FIG. 11  is a side view showing the operation of heat roller and conveyance roller shifting from section A to section B of  FIG. 8 . 
           [0059]      FIG. 12  is a side view showing the operation of heat roller and conveyance roller in the section B of  FIG. 8 . 
           [0060]      FIG. 13  is a side view showing the operation of heat roller and conveyance roller in the section C of  FIG. 8 . 
           [0061]      FIG. 14  is a side view showing the operation of heat roller and conveyance roller in the section D of  FIG. 8 . 
           [0062]      FIG. 15  is a side view showing the operation of heat roller and conveyance roller in the section E of  FIG. 8 . 
           [0063]      FIG. 16  is a front view showing a state in the other embodiment of  FIG. 5  wherein the heat roller of the movable block has moved away from the heat roller of the fixed block. 
           [0064]      FIG. 17  is a partial magnified side view of a heat roller showing the vertically sealable area by longitudinal sealer. 
           [0065]      FIG. 18  is a side view showing the operation of heat roller and conveyance roller before moving away the heat roller in one embodiment of varying the sealing intervals in a transverse direction while the conveying sheet is being conveyed. 
           [0066]      FIG. 19  is a side view showing the state wherein the heat roller of  FIG. 18  is moved away. 
           [0067]      FIG. 20  is a side view showing a state when the conveyance roller is rotated at a normal speed while the heat roller shown in  FIG. 19  is moved away. 
           [0068]      FIG. 21  is a side view showing a state when the conveyance rollers are rotated at a low speed while a heat roller shown in  FIG. 19  is moved away. 
           [0069]      FIG. 22  is a side view showing a state wherein the heat rollers of  FIG. 21  are contacted through the packaging sheet. 
           [0070]      FIG. 23  is a side view showing the operation of detaching and moving the heat rollers in the embodiment of varying the sealing intervals in a transverse direction while the conveying sheet is being conveyed. 
           [0071]      FIG. 24  is a side view showing a status wherein the heat rollers of  FIG. 23  are contacted through the packaging sheet. 
           [0072]      FIG. 25  is a side view showing a state wherein the heat rollers of  FIG. 23  have returned to the initial position by rotating while performing vertical sealing. 
           [0073]      FIG. 26  is a perspective view of heat sealing unit according to the second embodiment. 
           [0074]      FIG. 27  is a perspective view of the heat sealing part of  FIG. 26  as seen from a different angle. 
           [0075]      FIG. 28  is a perspective view of the heat sealing part of  FIG. 26  as seen from top. 
           [0076]      FIG. 29  is a perspective view of the fixed block of  FIG. 26 . 
           [0077]      FIG. 30  is a perspective view of the heat sealing part of  FIG. 26  as seen from a different angle. 
           [0078]      FIG. 31  is a perspective view of the heat roller of  FIG. 26 . 
           [0079]      FIG. 32  is a partial cross-sectional view of the movable block of  FIG. 26 . 
           [0080]      FIG. 33  is a block diagram of the medicine packing apparatus according to the second embodiment. 
           [0081]      FIG. 34  is a schematic explanatory diagram of a heat roller according to another embodiment. 
           [0082]      FIG. 35  is a plane view of the packaging sheet formed by the heat roller of  FIG. 34 . 
       
    
    
     DETAILED DESCRIPTION OF INVENTION 
       [0083]    Embodiments of the present invention will be described hereinafter with reference to the accompanying drawings, in which preferred exemplary embodiments of the invention are shown. The ensuing description is not intended to limit the scope, applicability or configuration of the disclosure. Rather, the ensuing description of the preferred exemplary embodiments will provide those skilled in the art with an enabling description for implementing preferred exemplary embodiments of the disclosure. It should be noted that this invention may be embodied in different forms without departing from the spirit and scope of the invention as set forth in the appended claims. 
       First Embodiment 
       [0084]      FIG. 1  and  FIG. 2  show a medicine packing apparatus  1  according to the first embodiment. This medicine packing apparatus  1  comprises a tablet feeding unit  2 , powder medicine feeding unit  3 , and packaging unit  4 . The tablet feeding unit  2  and powder medicine feeding unit  3 , which constitute the medicine supplier, are installed on top of a housing  6 . On the other hand, the packaging unit  4  is disposed inside the housing  6 . The front opening of housing  6 , excluding the medicine dispensing unit  7  through which packaged medicines are dispensed, is covered by an openable/closable one-way opening door-type cover  8  such that it can be opened/closed. When this cover  8  is opened, a worker will be able to access the packaging unit  4  that is housed inside the housing  6 . 
         [0085]    The tablet feeding unit  2  consists of a plurality of square-shaped tablet containers  11  arranged in a lattice shape, and one package quantity of tablets loaded manually into each square-shaped tablet container  11  is extracted automatically one by one, and delivered to the packaging unit  4 . 
         [0086]    Regarding the powder medicine feeding unit  3 , powder medicine is manually loaded inside a long box (V box  16 ) with a roughly V-shaped cross-section open on the housing  6 , and this powder medicine is divided into one package quantity each and supplied sequentially to packaging unit  4 . A movable partition plate  17  is disposed inside V box  16  to adjust the divided quantity of the powder medicine. 
         [0087]    The tablets or powder medicine supplied from the tablet feeding unit  2  or powder medicine feeding unit  3  through hopper  23  is packaged into each package by the packaging unit  4  with packaging sheet S. The packaging sheet S is wound on roll  28 , transformed ultimately in a sloping downward direction through the mediation of a plurality of rollers  26 , the lower end of the hopper  23  is positioned in the space that is formed by folding the sheet into V shape by a triangular plate. Regarding the packaging sheet S, to which the medicine was supplied through the hopper  23 , its opening is sealed in transverse and vertical directions by the heat sealing part  24  in the further downstream, and packaged as one package. It is also possible to rewind the packaging sheet S that is wound on the roll  28  in a state of being folded into two along the longitudinal direction. The conveyance roller  27 , which is a conveyance member provided rotatably in downstream of the conveying direction of the heat sealing part  24 , is driven by a guide motor  27   a , and holds and conveys the packaging sheet S that will be sealed by the heat sealing part  24 . 
         [0088]    The heat sealing part  24  according to the present invention, as shown in  FIG. 3 , consists of a fixed block  31  fixed to the housing  6  shown in  FIG. 1 , and a movable block  33  that rotates around a spindle  32 , which is provided at the top of this fixed block  31 , in a direction (direction a in the drawing) where the lower part moves away from the fixed block  31 , and that opens/closes with respect to the fixed block  31 . The position where the movable block  33  is closed to the fixed block  31  is the heat sealing position, and the position that is open and moved away is the working position for inserting the packaging sheet S. 
         [0089]    Both blocks  31  and  33  are provided with a heat roller  36  that is a sealer. Each of blocks  31  and  33  is provided with a corresponding bearing unit  37  to rotatably support the upper and lower part respectively of the shaft  36   a  of the heat roller  36 . The heat roller  36  consists of an annular longitudinal sealer  41  that has an approximately I cross-section in the axial direction and that is located in the upper end of the roller, and a rolling part  41   a  that has a shape same as that of the longitudinal sealer  41  and that is disposed at the lower end of the roller, and a transverse sealer  42  disposed between the longitudinal sealer  41  and rolling part  41   a . A heater (not shown in drawing) is accommodated inside the transverse sealer  42 , and this heater heats the transverse sealer  42  and longitudinal sealer  41 . 
         [0090]    A main gear  38  and a sub-gear  39  are integrated to the shaft part  36   a  which extends in the upper direction from the top end of the heat roller  36 . As the teeth of the main gear  38  is deep in the radial direction, it can mesh with the movable block  33  whether it is in heat sealing position or working position. When the movable block  33  is in heat sealing position, the main gears  38  and sub-gears  39  will respectively mesh with each other, and when the movable block  33  is in working position, the sub-gears  39  move away and the main gears  38  will mesh with each other. That is, by the open/close operation of the blocks  31  and  33 , the main gears  38  will definitely mesh with each other. Therefore, a driving force is transmitted from heat roller drive motor  40  to the main gear  38  of fixed block  31  via the drive gear  40   a . As a result, when the heat roller  36  is rotated via main gear  38  of fixed block  31  by driving the heat roller drive motor  40 , the heat roller  36  of movable block  33  also rotates in synchronization. Therefore, it will be possible to maintain a constant positional relationship between the two blocks  31  and  33 . Further, since one pair of heat rollers  36  is driven by one heat roller drive motor  40 , the structure of the heat sealing part  24  can be simplified. 
         [0091]    Because a trolley electrode  43  is provided between the main gear  38  and sub-gear  39 , and a power supply brush  44  is in sliding contact with this trolley electrode  43 , power is supplied to the heater. 
         [0092]    By connecting a support member  51  to each of the upper and lower bearings  37  of the heat roller  36  disposed in the movable block  33 , the heat roller  36  is disposed such that it can be moved in the b direction. The support member  51  includes a connecting part drive motor  52  which is a power source, a swing member  59  (see  FIG. 4 ) that can be rotatably driven around the spindle  65  by this connecting part drive motor  52 , and a connecting part  71  connecting this swing member  59  and bearing  37  of the heat roller  36 . 
         [0093]    A drive gear  53  is coupled to the connecting part drive motor  52 , and a driven gear  54  that meshes with the drive gear  53  is disposed on the rotating shaft  56 . Circular cam  57  is provided eccentrically at both ends of the rotating shaft  56 . 
         [0094]    The swing member  59  has a substantially L-shape in a plane view and is provided so as to be rotatable around a spindle  65  formed from a rod, and a long hole  60  is formed in one arm  62 , and the other arm  63  is connected to a connecting part  71  via a pin  66 . 
         [0095]    By passing the spindle  65  through the holding member  61  disposed on both sides of the swing member  59 , the swing member  59  is held rotatably in the holding member  61 . Bearing  58  is fitted in the long hole  60 , and the swing member  59  is coupled to the cam  57  via this bearing  58 . By providing a long hole  60 , even when the eccentric cam  57  rotates, the interference between this cam  57  and swing member  59  can be avoided, and the swing member  59  will be able to rotate. When the cam  57  rotates, arm  62  moves in the upper/lower direction, and the swing member  59  rotates around the spindle  65 , and as a result, the arm  63  moves in direction b in the drawing or in its opposite direction. 
         [0096]    The connecting part  71  is comprised of a swing member side rod  72  connecting to pin  66 , a heat roller side rod  76  that secures a bracket  74  fixed to the outer circumference of the bearing  37  of shaft  36   a  of the heat roller  36 , and a cylindrical rod-connecting part  79  that connects the swing member side rod  72  and the heat roller side rod  76 . A threaded section  75  is formed in the outer circumference of the swing member side rod  72 , and a first nut  73  is screwed to this threaded section  75 . Similarly, a threaded section  75  is formed in the outer circumference of the heat roller side rod  76 , and a second nut  77  is screwed to this threaded section  75 . A tooth part  79   a  is formed on the swing member  59  side of the rod connecting part  79  and in an inner circumference thereof, and this tooth part  79   a  is engaged with the threaded section  75  of the swing member side rod  72 . By tightening the first nut  73  and rod connecting part  79  to the threaded section  75  so that the first nut  73  and the rod connecting part  79  contact, both of the members  73  and  79  are fixed to the swing member side rod  72 . A flange  79   b  is formed in the inner peripheral surface of the opened end side of the heat roller  36  of the rod connecting part  79  A configuration is provided in which the second nut  77  is positioned away from the flange  79   b , so that when the rod connecting part  79  moves in direction b, the second nut  77  engages with the flange  79   b , and moves the heat roller side rod  76  in direction b. A spring member  78  is externally inserted in the heat roller side rod  76 , and one end of this spring member  78  is engaged with a bracket  74  and the other end is engaged with a rod connecting part  79 . With this configuration, at all times, the heat roller  36  is always biased by the spring member  78  in the direction of the other heat roller  36 . Further, as the spring members  78  are engaged with the rod connecting part  79 , by varying the fixing position of the rod connecting member  79 , the biasing force of the heat roller  36  by the spring members  78  can be adjusted. 
         [0097]    When the swing member  59  rotates in direction b, through the swing member side rod  72 , the rod connecting member  79 , second nut  77  and heat roller side rod  76 , the heat roller  36  is moved in direction b by resisting the biasing force of the spring member  78 . Also, by changing the fixing position of first nut  73  and rod connecting member  79  in swing member side rod  72 , the length of the connecting part  71  can be adjusted. 
         [0098]    As shown in  FIG. 6 , a conveyance roller  27 , guide motor  27   a , heat roller drive motor  40  and connecting part drive motor  52  are respectively connected to the controller  83 , and they are controlled based on the signals from this controller  83 . 
         [0099]    Next, operation of the heat roller  36  having the above-mentioned configuration is described. 
         [0100]    Referring to the flowchart shown in  FIG. 7 , the controller  83  detects whether the amount of medicine to be packaged is normal or small based on the prescription data in step S 1 . If the amount of the medicine is normal, it will proceed to step S 2 , and the controller  83  rotates the conveyance rollers  27  as shown in region A in  FIG. 8 . Then, it will proceed to step S 3 , by rotating with the heat rollers  36  in a closed state, that is, in a state wherein the longitudinal sealers  41  are attached through the packaging sheet S, the packaging sheet S can be sealed by maintaining the sealing intervals in transverse direction at a constant interval L 3  (see  FIG. 9 ). Here, the longitudinal sealer  41  seals the packaging sheet S in the vertical direction by rolling on the opening of the packaging sheet S. Further, both of the edge sections of the transverse sealer  42  come in contact with the packaging sheet S with every half rotation and seal the sheet in the transverse direction. By integrating the longitudinal sealer  41  and the transverse sealer  42 , a temperature difference within the heat rollers  36  is eliminated and it becomes possible to seal the packaging sheet S at a desired temperature. Therefore, since packaging sheet S made of cheaper material having a small difference between the fusion temperature and heat resistance temperature can be used, it becomes possible to reduce the manufacturing cost of packaging sheet S. A material having a small difference between the fusion temperature and heat resistance temperature includes PET (polyethylene terephthalate) and PS (polystyrene). Conventionally, cello poly having a large difference between the fusion temperature and heat resistance temperature was used as a material of packaging sheet S, but the cost of PET is cheaper by 20-30% and that of PS is cheaper by 30-40% than cello poly, and it becomes possible to lower the cost of the packaging sheet S according to present invention. Regarding the heat rollers  36 , as shown in  FIG. 10 , the heat roller  36  at top in the drawing is rotated clockwise to rotate the heat roller  36  below anticlockwise (hereafter referred as normal rotation). 
         [0101]    If the amount of the medicine to be packaged is small, the said interval L 3  needs to be narrowed. Therefore, it will proceed to step S 4 , and as shown in  FIG. 11 , rotation of heat rollers  36  and conveyance rollers  27  are stopped in section B of  FIG. 8 . Next, proceeding to step S 5 , the controller  83  detaches the heat rollers  36  from a closed state (see  FIG. 12 ). More specifically as shown in  FIG. 4 , by driving the connecting part drive motor  52 , the swing member  59  is moved in direction b by cam  57  via drive gear  53  and driven gear  54 . By doing so, through the mediation of swing member side rod  72 , rod connecting member  79  and heat roller side rod  76 , the shaft  36   a  of heat roller  36  of movable block  33  is moved in the b direction. This produces a space L 1  between the heat roller  36  of the fixed block  31  and the heat roller  36  of the movable block  33  (see  FIG. 5 ). This space L 1  here is 0.5 mm, however, it is not particularly limited. Then, in step S 6 , with the packaging sheet S in a stopped state, as shown in section C of  FIG. 8 , the heat rollers  36  are normally rotated in a detached state in  FIG. 13 . As a result, the heat rollers  36  rotate idly. In section D of  FIG. 8 , while maintaining a state in which rotation of the conveyance rollers  27  is stopped as shown in  FIG. 14 , proceeded to step S 7 , rotation of heat rollers  36  is stopped, and in step S 8 , the heat rollers  36  are moved to a closed state from an open state. More specifically, by continuing to drive the above-mentioned connecting part drive motor  52 , the swing member  59  is moved in a direction opposite to the direction b driven by the cam  57 . As a result, the shaft  36   a  of the heat roller  36  is also moved in the same direction, and the heat rollers  36  are closed. On proceeding to step S 9 , in the region E of  FIG. 8  as shown in  FIG. 15 , with the heat rollers  36  in contact with each other through the packaging sheet S, the conveyance rollers  27  and heat rollers  36  are normally rotated. As a result, the side is sealed by the longitudinal sealer  41  while the sheet S is being conveyed, and sealing is continued in the transverse direction by the transverse sealer  42  at intervals of a spacing L 4 . Thereupon, this flow is finished, and returns to step S 1  again. With the above operations, the sealing interval in a transverse direction by transverse sealer  42  can be narrowed by the amount of idling (normal rotation) of the heat rollers  36  in section C. 
         [0102]    Moreover, when moving the heat rollers  36  from a detached state to an attached state, the portion sealed by longitudinal sealer  41  overlaps as shown in  FIG. 9  resulting in an undesirable appearance, and therefore, it is preferable that heat rollers  36  are attached and detached at a timing such that this overlapped seal portion  81  occurs at an end portion of each package. 
         [0103]    An angle of 60°, for example, is used as an angle of idling (normal rotation)  0  for the heat rollers  36 , however, the same effect can be obtained by idling (normally rotating) at 240° and 420°. Further, by decreasing the angle θ to less than 60°, it is possible to increase the sealing interval in the transverse direction as compared to the case of 60°, and by increasing the angle θ greater than 60° and less than 90°, the above-mentioned sealing interval of the transverse direction can be further decreased. With these, the angle θ can be adjusted according to the desired sealing interval. 
         [0104]    Various angles may be used for the angle θ. For example, by idling (normally rotating) at more than 90°, that is, at 110°, 170°, 290° or 350°, the sealing interval in the transverse direction can be increased as compared to the normal angle, and by idling (normally rotating) at 190°, 220°, 370° or 400°, the sealing interval in the transverse direction can be reduced as compared to the normal angle. 
         [0105]    In the present embodiment, the heat rollers  36  are detached from a state where the transverse sealers  42  are located in the horizontal direction in section B, but it is possible to obtain the similar effect by having a configuration of hastening or delaying the timing of detachment. 
         [0106]    Here, in the present embodiment, though the heat rollers  36  were rotated in normal direction in section C for the case of the amount of medicine being less than usual, in case of the amount of medicine being more than usual, it is possible to use a configuration wherein the heat roller  36  at top in the drawing is rotated in the anticlockwise direction and the heat roller  36  at the bottom is rotated in a clockwise direction (hereafter referred to as inversion). With this, it is possible to widen a sealing interval in the transverse direction of the packaging sheet S. Moreover, although 10° may be employed, for example, as an angle θ of idling (inverting) the heat roller  36 , it is possible to obtain the similar effect by idling (inverting) at 190° and 370°, and there is no particular limitation as long as the sealing interval in the transverse direction can be increased. On the other hand, if 110°, 170°, 290° or 350°, for example, is used as the idling (inversion) angle, the sealing interval in the transverse direction can be reduced as compared to the normal angle. 
         [0107]    As it is possible to broaden the sealing intervals in the transverse direction without increasing the diameter of the heat rollers  36 , the manufacturing cost of heat rollers  36  can be reduced and heat can be transferred efficiently to sealers  41  and  42  as compared to the case of increasing the diameter. Therefore, the preheating time for heating the sealers  41  and  42  can be reduced so that sealing can be carried out immediately after switching on the medicine packing apparatus  1 , and the amount of heat required to heat the sealers  41  and  42  can also be reduced. 
         [0108]    The present invention is not limited to the above embodiment, and various modifications are possible. 
         [0109]    In the embodiment described above, one heat roller  36  was slid parallel to the other heat roller  36 , but it is not limited to this, and as shown in  FIG. 16 , it is possible to connect only the bearing  37 , which is located on the longitudinal sealer  41  of the heat roller  36  disposed on the movable block  33 , to the connecting part  71 . Here, the other bearing  37  is tiltably fixed to the movable block  33  by a known method. Thereupon, the similar effect can be obtained by adopting a configuration wherein a predetermined interval L 2  is created between the heat rollers  36  by having the connecting part  71  pull the bearing  37  and rotating the heat roller  36  around the shaft. 
         [0110]    Also, in the embodiment described above, a packaging sheet S was sealed at the both edges of the transverse sealer  42 , that is, in two places, but it is also possible to use a configuration to seal at only one edge. With this, it is possible to increase the adjustment margin of sealing in the transverse direction. 
         [0111]    In the embodiment described above, conveyance of the packaging sheet S was stopped when the heat rollers  36  are detached, however, it is possible to adopt a configuration wherein the heat rollers  36  are detached while conveying the packaging sheet S. Referring to  FIG. 17 , following description is provided based on an assumption that the longitudinal sealer  41  can seal the packaging sheet S by welding within the range shown in vertically sealable region W. 
         [0112]    As shown in  FIG. 18 , the conveyance rollers  27  and heat rollers  36  are normally rotated and sealing is being done in the longitudinal direction by the longitudinal sealer  41  while conveying a packaging sheet S. Here, an optional point F on the packaging sheet S is located in the vertically sealable region W. In order to narrow the sealing interval L 3  by transverse sealer  42 , the heat rollers  36  are detached while normally rotating the conveyance roller  27  as shown in  FIG. 19 , and a conveying speed of the packaging sheet S by the conveyance rollers  27  is set to a low speed. Then, the heat rollers  36  are idled (normal rotation) only by an angle θ. If the packaging sheet S is conveyed at an usual speed while the heat rollers  36  are detached, the point F deviates from the vertically sealable region W (see  FIG. 20 ), and if the heat rollers  36  are again contacted through the packaging sheet S, a gap is formed in the vertical sealing region of the packaging sheet S. However, by reducing the conveying speed of the packaging sheet S as described above, when the heat rollers  36  are again contacted through the packaging sheet S as shown in  FIG. 22 , it becomes possible to maintain the point F within the vertically sealable region W. In this way, the packaging sheet S can be vertically sealed continuously, and apart from preventing the formation of gaps, the sealing interval in the transverse direction can be narrowed. However, the sealing interval in the transverse direction can be small or large by changing the angle θ as described above. 
         [0113]    In the present embodiment, the conveying speed of the packaging sheet S was set to low speed, however, as long as point F is maintained inside the vertically sealable region W while the heat rollers  36  are detached, there is no restriction to this. For example, the similar effect can be obtained when the heat rollers  36  are idled at high speed and the speed of detachment and attachment is increased while maintaining the normal conveying speed instead of low speed. 
         [0114]    In addition, another embodiment of detaching the heat rollers  36  while conveying the packaging sheet S will be described. In the above embodiment, in  FIG. 19 , in addition to detaching the heat rollers  36  while normally rotating the conveyance rollers  27 , the conveying speed of the packaging sheet S by the conveyance rollers  27  was reduced. However, it is possible to have a configuration wherein, while maintaining a constant conveying speed of conveying sheet S, the heat rollers  36  can be detached and moved in the conveying direction of the conveying sheet S as shown in  FIG. 23 . Here, in addition to moving the heat rollers  36 , they are also idled only by an angle θ in the normal rotation direction. With this, as shown in  FIG. 24 , when the heat rollers  36  are again contacted through the sheet S, the point F can be maintained inside the vertically sealable region W and the sealing intervals in the transverse direction can be made smaller. Thereupon, as shown in  FIG. 25 , the heat rollers  36  are rotated quickly and returned to an initial position while the heat rollers  36  are in contact with the packaging sheet S and vertically sealing the sheet. 
       Second Embodiment 
       [0115]    The configuration of heat sealing part  101  according to another embodiment is shown in  FIG. 26  through  FIG. 33 . The heat sealing part  101  is different from that of the above-mentioned embodiment mainly in a mechanism to facilitate idling by rotating the movable heat roller  127  to detach it from the packaging sheet S. 
         [0116]    As shown in  FIG. 29 , the fixed block  102  is comprised of a plate-shaped attaching part  103 , a first holding part  104  continuous with one end of the attaching part  103 , and a second holding part  105  that protrudes orthogonally from the other end of the attaching part  103 . 
         [0117]    By providing a protrusion  106  in the middle of one side of the attaching part  103 , the strength of the attaching part  103  can be increased, and its both sides can be fixed, as appropriate, to the inner surface of housing  6  or the like by screws. 
         [0118]    The first holding part  104  is of roughly U shape, and in the corners of two facing walls, through-holes  104   a  are respectively provided for rotatably supporting the shaft member  128  for connecting the movable block  123  rotatably. Also, at the bottom of the first holding part  104 , as shown in  FIG. 26 , an inverted L-shaped mounting plate  107  projecting in the same direction as the both side walls is provided, and motor for conveyance  108  is installed therein. A drive gear  109  is fixed to the rotating shaft of the motor for conveyance  108 , and through a driven gear  110  that meshes with this drive gear  109 , a pair of conveyance rollers  111  and  113  can be driven to rotate. 
         [0119]    The conveyance rollers  111  and  113 , as shown in  FIG. 30 , are supported opposite to mounting plate  107  at the bottom of the first holding part  104 . One conveyance roller (the first conveyance roller  111 ), is rotatably installed in one end of the operating arm  112  that is rotatably supported at the bottom of the first holding part  104  with spindle  111   a  as a center. As for the other conveyance roller (second conveyance roller  113 ), a driven gear  110  is fixed to the rotating shaft of the other conveyance roller, and through the interlocking gears  114   a  and  114   b , the second conveyance roller  113  can be rotated synchronously with the first conveyance roller  111 . With the help of a spring (not shown) provided in the operating arm  112 , the first conveyance roller  111  is biased towards the second conveyance roller  113 . When operating arm  112  is rotated, the first conveyance roller  111  can be detached from the second conveyance roller  113 , and can be used when setting, attaching or removing the packaging sheet S for maintenance or the like. 
         [0120]    The tip of the second holding part  105 , as shown in  FIG. 29 , is roughly U shape, and its inside is provided with a slot portion  105   a . A bearing  122  mounted at the lower end of the fixed heat roller  115  is disposed in this slot portion  105   a.    
         [0121]    The fixed heat roller  115 , as shown in  FIG. 30 , is in the shape of a long cylinder and can be formed, for example, by casting ductile cast iron. A heater (not shown) is provided in the center hole  115   a  of the fixed heat roller  115 . The shape of the cross-section along the length direction of the fixed heat roller  115  is formed roughly in an I shape from the lower end to a predetermined location in the upper direction, and constitutes a sealing part comprised of a longitudinal sealer  116  and transverse sealer  117 , and an auxiliary roller unit  118 . The longitudinal sealer  116  is an outer circumferential surface of the cylinder disposed at one end of the fixed heat roller  115 . The auxiliary roller unit  118  is provided at the other end of the fixed heat roller  115 , and has the same shape as that of the longitudinal sealer  116 . The transverse sealer  117  is an area (part of the outer circumference) of a predetermined width dimension connecting the longitudinal sealer  116  and auxiliary roller unit  118 . A saw blade cross-section is formed by providing a plurality of slots along the circumference direction in each sealing part  116 ,  117  and auxiliary roller unit  118 . With this, in addition to making it difficult to cause sliding between the longitudinal sealer  116  or transverse sealer  117  and packaging sheet S, seal unevenness is unlikely to occur as compared to contacting with the entire surface, and satisfactory sealing condition can be achieved. Further, a slot is formed in the center of the transverse sealer  117 , and a cutting blade member (not shown) is disposed therein. The cutting blade member is for providing a cutting section in a broken line in the transversely sealed portions of the packaging sheet S. 
         [0122]    In the upper part of the fixed heat roller  115 , a main gear  119 , sub-gear  120 , bearing  121  and one pair of trolley electrodes  154  are respectively provided. The main gear  119  is configured of spur gear, and when the rotating shaft of a movable heat roller  127  (described later) is arranged in parallel, it will mesh with main gear  142 . On the other hand, the sub-gear  120  has a configuration wherein a spur gear and a bevel gear are integrated, and meshes with the spur gear of the sub-gear  143  of the movable block  123 , and when the movable block  123  is rotated, it will mesh with the bevel gear. A flange  155  supported by a spring is in a sliding contact with the trolley electrode  154  so that electric power can be supplied to a built-in heater (not shown). Also, a bearing  122  is provided at the bottom end of fixed heat roller  115 . The fixed heat roller  115  is rotatably supported to the fixed block  102  by fitting the upper bearing  121  in the through-hole formed at the bottom of the first holding part  104 , and disposing the lower bearing  122  in the slot portion  105   a  of the second holding part  105 . 
         [0123]    As shown in  FIG. 26 , power can be transmitted to the fixed heat roller  115  from a drive motor (not shown) via an intermediate gear member  150 . In the intermediate gear member  150 , a spur gear  152  that meshes with the main gear  119 , and bevel gear  153  that meshes with the bevel gear provided in the rotating shaft of the drive motor are integrated to the rotating shaft  151 . A triangular plate  102   a  is attached to the fixed block  102  for folding the packaging sheet S into a V shaped transverse cross-section along the length direction. 
         [0124]    The movable side block  123 , as shown in  FIG. 27 , has the configuration almost similar to the fixed block  102 , and configured from an attaching part  124 , a first holding part  125  and a second holding part  126 , and rotatably supports a movable heat roller  127 . 
         [0125]    Through-holes (not shown) are respectively provided in the corner on both side walls of the first holding part  125 . Thereupon, a shaft member  128  is inserted through the holes and the through-holes  104   a  of the fixed block  102 , and a movable block  123  is connected rotatably to the fixed block  102 . 
         [0126]    A fulcrum  129  is fixed in the upper part of both walls of the first holding part  125 . A first mounting plate  131  to anchor a motor for rotation  130 , a second mounting plate  132  to mount light sensors  136  and  137 , and a guide member  133  are fixed respectively to the fulcrum  129 . 
         [0127]    In the middle of rotating shaft of the motor for rotation  130 , two disks (first disk  134  and second disk  135 ) to be detected are mounted respectively in axially deviating positions. A notch (or opening) is provided in circumferentially deviating position of each of the disks  134  and  135 . Each notch is formed such that the respective positions can be detected respectively by the light sensors (first light sensor  136  and second light sensor  137 ). At the position where the notch of the first disk  134  is detected by the first light sensor  136 , the movable heat roller  127  is positioned at a sealing position, and at the position where the notch of the second disk  135  is detected by the second light sensor, the movable heat roller  127  moves to a retracted position. 
         [0128]    One end of a connecting bar  138  is rotatably connected to the tip of the rotating shaft of the motor for rotation  130 . At the other end of the connecting bar  138 , the projecting part of a substantially T-shaped moving piece  139  is rotatably connected. A screw member  140  is mounted respectively at both ends of the pressing part of the moving piece  139 . 
         [0129]    The respective screw members  140  are inserted through the guide hole (not shown) provided in the guide member  133 , and the tip section is inserted through the through-hole (not shown) of the pressing accepting member  144  (described later). In the middle of each screw member  140 , a nut  141  is screwed between the guide member  133  and pressing accepting member  144 . This nut  141 , when the connecting bar  138  is moved by driving the motor for rotation  130 , functions as an action point for rotating the movable heat roller  127  by contacting with the pressing accepting member  144 . Therefore, if the screwing position of the nut  141  is varied, the extent of rotation of the movable heat roller  127  can be adjusted. 
         [0130]    The movable heat roller  127  is rotatably supported by the first holding part  104  and second holding part  105  of the movable block  123 . The movable heat roller  127 , as shown in  FIG. 30 , has a configuration similar to that of the above-mentioned fixed heat roller  115 . Namely, the movable heat roller  127  is comprised of a built-in heater (not shown) in the center hole  127   a , a longitudinal sealer  146 , a transverse sealer  147 , auxiliary roller unit  148 , bearings  149   a ,  149   b  and trolley electrode  156 . The movable heat roller  127  can rotate with the contacting position of auxiliary roller units  118  and  148  as fulcrum, in a space between the movable heat roller  127  and the fixed heat roller  115 , to a sealing position wherein the longitudinal sealers  116  and  146  contact each other through the packaging sheet S and to a retracted position where they are detached. However, one end where a main gear  142  and sub-gear  143  are disposed is further extended, and a pressing accepting member  144  is mounted therein. 
         [0131]    The movable heat roller  127 , as shown in  FIG. 32 , is biased towards the fixed heat roller  115  as the bearings  149   a  and  149   b  are pressed by a first coil spring  161   a  and a second coil spring  161   b  (bias members) that are provided in the movable block  123 . The first coil spring  161   a  and the second coil spring  161   b  are disposed inside the through-holes  123   a  and  123   b  respectively formed in the movable block  123 . Female threading is provided in the inner surface of the through-holes  123   a  and  123   b , and cylinders  163   a  and  163   b  having male threading in the outer periphery are respectively screwed to there. By adjusting the screwing positions of the cylinders  163   a  and  163   b , pressing force of the first coil spring  161   a  and the second coil spring  163   b  can be changed, and the biasing force created by the movable heat roller  127  can be adjusted. Such adjustment of biasing force is done at the time of initial setup or at the time of maintenance so that the holding force between the longitudinal sealers  116  as well as  146  and transverse sealers  117  as well as  147  can be adjusted to achieve a proper sealing of the packaging sheet S. 
         [0132]    The pressing accepting member  144 , as shown in  FIG. 28 , is comprised of cylindrical section  144   a  locking with one end of the movable heat roller  127 , and one pair of arms  144   b  extending to both sides therefrom. Through-holes (not shown) are formed in both arms  144   b , and the tip of the screw member  140  is inserted in there. 
         [0133]    The movable block  123  of the above configuration, as shown in  FIG. 28 , is connected to the fixed block  102  by locking the hook member  154  provided rotatably in the second holding part  126  with the second holding part  105  of the fixed block  102 . At maintenance and the like, by releasing the locking state of the hook member  154 , the movable block  123  can be rotated and detached from the fixed block  102 . 
         [0134]    In a movable block  123  of the above configuration, as shown in  FIG. 26 , all of the mechanisms (for example, motor for rotation  130 , connecting bar  138 , screw member  140 , pressing accepting member  144 , etc.) for rotating the movable heat roller  127  can be disposed on the heat sealing part  101  that is mounted inside the housing  6 . Since the space on the heat sealing part  101  was originally a dead space, by effectively utilizing this dead space, it is possible to prevent an increase in the size of the apparatus. If the mechanisms are disposed in front of the heat sealing part  101  such as the support member  51  shown in the first embodiment, an extra space in the housing  6  may be required in the front side of the medicine packing apparatus  1 , but there is no need for this concern. Since there are no items to be disposed in front of the heat sealing part  101 , it becomes possible to adjust the biasing force of movable heat roller  127  with a simple configuration, which was difficult in the above-mentioned embodiment. 
         [0135]    The input signals from the above-mentioned sensors  136  and  137  etc., as shown in  FIG. 33 , are fed to the controller  145 . The controller  145  executes the packaging process by driving and controlling the motors  108  and  130  etc. based on the input signals. 
         [0136]    Here, the operation of the heat sealing part  101  of the above configuration will be explained. Basic operations are same as those of the embodiment mentioned above (see flowchart and related explanations in  FIG. 7 ), but differs only with regard to the configuration of moving the movable heat roller  127  to a retracted position. That is, in case the transverse sealing position of the transverse sealer  117  is changed based on the quantity of the medicine to be packaged, rotation of the heat rollers  115  and  127 , and conveyance rollers  111  and  113  are stopped (step S 4 ), and the motor for rotation  130  is driven (step S 5 ). The motor for rotation  130  continues to be driven until the notch of the second disk  135  is detected by the second light sensor  137 . With this, the movable heat roller  127  rotates to the retracted position from the sealing position. Because the movable heat roller  127  simply rotates with the contact section of the auxiliary roller units  118  and  148  as a fulcrum, the operation is smooth and stable although the configuration is simple as compared to the case of parallely moving the entire unit. Thereupon, by similarly idling both heat rollers  115  and  127  in a state wherein the movable heat roller  127  is moved to the retracted position, the position of transverse sealer  117  is adjusted (steps S 6  and S 7 ). Subsequently, by driving the motor for rotation  130 , the movable heat roller  127  is returned to the original sealing position (step S 8 ), and sealing is resumed (step S 9 ). 
         [0137]    Here, because of an integral structure in which the same material is used for the fixed heat roller  115  and the movable heat roller  127 , a difference in the heating temperature is not likely to occur between the longitudinal sealer  116  and transverse sealer  117 . In other words, uniform heating of the packaging sheet S becomes possible regardless of vertical sealing position or transverse sealing position, and sealing unevenness does not occur. Therefore, despite of using a configuration of detaching the movable heat roller  127  from the packaging sheet S, it becomes possible to provide an excellent sealing condition for the packaging sheet S. 
         [0138]    Furthermore, in the embodiment mentioned above, a configuration was provided in which the movable heat roller  127  is rotated by resisting the biasing force of the first coil spring  161   a  to detach the movable heat roller  127  from the fixed heat roller  115 , but the following configuration is also possible. 
         [0139]    Namely, as shown in  FIG. 34 , the heat rollers  115  and  127  are configured from a first heat roller  201  and a second heat roller  202  that are rotatable. Then, although biasing of the first heat roller  201  towards the second heat roller  202  by coil spring (not shown) is similar to the embodiment described above, it differs with regard to pulling the upper part of the second heat roller  202  so as to rotate to detach from the first heat roller  201 . The position of pulling the second heat roller  202  may be the shaft  204  projecting from the longitudinal sealer  203 . As a mechanism for pulling the shaft  204 , a mechanism of the second embodiment for rotating the movable heat roller  127 , or a known cam mechanism or a link mechanism may be used. 
         [0140]    Here, since the first heat roller  201  is biased towards the second heat roller  202  by a coil spring, if the second heat roller  202  is pulled and moved, there is a risk of the first heat roller  201  losing the support of the second heat roller  202  and moving beyond the position of abutment. Therefore, it is preferable to provide a stopper (not shown) so that the first heat roller  201  does not move more than necessary. The stopper, for example, may be provided in the movable block  123 , and located between the longitudinal sealer  206  of the first heat roller  201  and the longitudinal sealer  207  of the second heat roller  202  (described later). 
         [0141]    In addition, in the heat rollers  115 ,  127  and  201 ,  202 , the longitudinal sealers  116 ,  146  and  205 ,  203  and transverse sealers  117 ,  147  and  206 ,  207  are integrally formed. Therefore, by providing continuous cutting blades  208  and  209  in both sealing parts, it becomes possible to form a perforation S 1  that cuts across the packaging sheet S in the width direction as shown in  FIG. 35 . Further, it becomes possible to minimize the temperature difference between the longitudinal sealers  116 , 146  and  205 ,  203 , and transverse sealers  117 , 147  and  206 ,  207 . Consequently, it becomes possible to use an inexpensive material with a small difference between the welding temperature (sealable temperature) and the melting temperature for a packing sheet S, and to increase options for the material. In particular, a material having excellent moisture resistance suitable for packaging of medicines, which could not be used in the past, can be used. Specifically, cello poly (made from cellophane and polyethylene) having a moisture permeability of 15 g/m 2 ·24 h (room temperature 30° C., humidity 90%) was conventionally used, however, currently, it became possible to use a newly developed material having a moisture permeability of 10 g/m 2 ·24 h (room temperature 30° C., humidity 90%). 
         [0142]    Further, as for the heat rollers  115 ,  127  and  201 ,  202 , it is preferable to detach them from the packaging sheet S when the packaging operation is not being performed. With this, it becomes possible to prevent the occurrence of problems such as the packaging sheet S becoming heated and melting, or adhering to the heat rollers  115 ,  127  and  201 ,  202  when the packaging operation is not happening. 
         [0143]    While the principles of the disclosure have been described above in connection with specific apparatuses and methods, it is to be clearly understood that this description is made only by way of example and not as limitation on the scope of the disclosure.