Abstract:
An apparatus for air guidance in a processing chamber has a housing with an entrance gate and an exit gate. Inside the housing the processing chamber is embodied for filling and sealing small bottles or ampules. The processing chamber is separated from an outside region via an intermediate region. The intermediate region having a movable door by means of which manual interventions in the processing chamber can be made. The apparatus also has a ventilation system with a blower and a clean-air filter which inside the processing chamber generates a laminar air flow. By means of special air pressure ratios in the processing chamber the intermediate region the entrance gate and the exit gate, the occurrence of contamination, or its exceeding a tolerable amount, in the processing chamber ( 12 ) and the outside region is avoided.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a 35 USC 371 application of PCT/DE 00/03396 filed on Sep. 27, 2000. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to a method and an apparatus for air guidance in a processing chamber and in particular, to a method of and an apparatus for dispensing pharmaceuticals or similar products into packaging containers inside a housing of a packaging machine is intended. 
     2. Description of the Prior Art 
     Known apparatuses of the type with which this invention is concerned are often constructed by so-called isolator technology; that is, the filling and sealing of the packaging containers are done under clean-room conditions, so that neither the previously sterilized packaging containers nor the product can become contaminated from external factors. To that end, the filling and sealing region of the apparatus in particular is surrounded by a housing, in which the air located in the interior is either recirculated through a clean-air filter, or else constantly cleaned air is delivered from outside through a clean-air filter (European Patent Disclosure EP 0 604 925 B1). Also in such apparatuses, it is often necessary to be able to make manual interventions from outside in the production chamber, for example to adjust equipment. Intervention using gloves (EP 0 604 925 B1) and free intervention without gloves are both known methods. In the latter option, there is always the risk either of contamination of the production room from outside or contamination of the outside region from the production room itself. 
     SUMMARY OF THE INVENTION 
     The object of the invention is therefore to embody a method of and an apparatus for air guidance in a processing chamber in such a way that contamination of both the processing chamber or production room and of the outside region, from which manipulations in the production room are made, is precluded or at least reduced to a certain tolerable amount. This object is attained with a method and an apparatus according to the invention which are distinguished in that at the instant when interventions into the production room are made, in particular through a gap between the production room and the outside region, air flowing out of the production room in the direction of the outside region and vice versa is aspirated away via an interstice and thus cannot reach the respectively other region. 
     Further advantageous refinements of the method according to the invention and of its apparatus will become apparent from the description contained below, taken with the drawings, in which: 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a schematic plan view of an apparatus for dispensing pharmaceuticals or similar products into packaging containers; 
     FIG. 2 is a simplified front sectional view of a bottling system of isolator construction; and 
     FIG. 3 is a fragmentary section taken along the plane III—III of FIG. 2 in the inflow region of the bottling systems. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The apparatus  10  for dispensing dry pharmaceuticals, in particular, or similar products into packaging containers, such as small bottles  1 , and sealing them has a housing  11 . The housing  11  encloses a production chamber  12 , in which processing devices, not shown because they are not essential to the invention, and in particular filling and sealing devices, are disposed. The bottles  1  are shunted by means of a conveyor system along a transport path  13  through the production chamber  12 , and the housing  11  has one entrance gate  15  and one exit gate  16 . The entrance gate  15  and the exit gate  16  each form one gate region  17 ,  18 , which have first openings  19  from the outside region  20  of the apparatus  10  into the gate region  17 ,  18  and second openings  21  from the gate region  17 ,  18  into the production region  12 . The size of the openings  19 ,  21  is preferably adapted to the size of the bottles  1  or is variable, so that the size of the openings  19 ,  21  is as small as possible, to avoid an excessive exchange of air among the various regions. 
     To make it possible to make manual interventions in the production chamber  12 , an access capability is embodied on side of the housing  11 , in the form of a double-disk door  22 . The door  22  has a first disk  24  toward the production chamber  12  and a second disk  23  toward the outside region  20 . The spacing of the two disks  23 ,  24  amounts to approximately 40 mm, for example. In order to indicate that the door  22  does not close the housing  11  in airtight fashion, gaps  26 ,  27  are drawn in in the region of the two disks  23 ,  24 , toward the housing wall; by way of these gaps, a purposeful exchange of air takes place between the production chamber  12  and the interstice  25 , between the two disks  23 ,  24 , and between the outside region  20  and the interstice  25 . 
     The access capability in the production chamber  12  exists in particular because the door  22  is embodied so as to be displaceable, or raisable and lowerable, thus creating a slit or free space through which one can reach manually into the production chamber, 12 . If the door  22  is open, then air can reach the interstice  25  via the slit or free space thus formed. It is also conceivable, at least in the one disk  24 , also to provide a hole, through which a glove fastened to the other disk  23  (on the side toward the production chamber  12 ) can be guided. 
     On the side of the transport path  13  opposite the door  22 , a ventilation system  28  is disposed in the housing  11 ; in the exemplary embodiment, it is separated from the production chamber  12  by an air-permeable device  29 . The ventilation system  28  has a blower  31  and a filter following it, in the form of a clean-air filter  32 . In the region of the ventilation system  28 , on the suction side of the blower  31 , the housing  11  has a first adjustable flap  33 , to allow the controlled delivery of air from the outside region  20 . On the pressure side of the blower  31 , a second adjustable flap  34  is also provided, to enable the outflow of cleaned air into the outside region  20 . 
     The apparatus  10  is embodied especially to prevent both contamination of the production chamber  12  from the outside region  20  and contamination in the opposite direction. To that end, the interstice  25  between the two disks  23 ,  24  communicates with the suction side of the blower  31  via a suction device or suction line, creating a flow path  36  for air. Further flow paths  37  for air are formed by the entrance gate  15  and the exit gate  16  toward the suction side of the blower  31 . From the blower  31 , the air cleaned in the clean-air filter  32  is carried into the production chamber  12 , and a substantially horizontally extending, laminar air flow  38  is created, which flows via the processing spaces or processing faces of the bottles  1  in the direction of the interstice  25 . 
     What is essential here is the different air pressure ratios in the various rooms or regions: In the production chamber  12 , a higher pressure thus prevails than in the intermediate region  25  or in the entrance gate  15  and the exit gate  16 . In addition, the pressure in the intermediate region  25 , the entrance gate  15  and the exit gate  16  is less than in the outside region  20 ; that is, in these regions, in comparison with the outside region  20 , a negative pressure prevails. As a consequence, not only does air from the outside region  20  flow via the first openings  19  into the entrance gate  15  and the exit gate  16 , but also air via the gaps  27  or upon opening of the door  22  flows via the thusformed gap or free space into the intermediate region  25 , as is meant to be indicated by the flow arrows  39 . Air also flows out of the production chamber  12  via the second openings  21  into the entrance gate  15  and the exit gate  16 , and air flows via the gaps  26  into the intermediate region  25 , as is indicated by the flow arrows  40 . Thus no air flow of uncleaned or contaminated air takes place out of the region outside the production chamber  12  into the production chamber  12 . Nor does any uncleaned or contaminated air flow out of the production chamber  12  into the outside region  20 . Contamination of the intermediate region  25  and of the gate regions  17 ,  18  from air emerging from the production chamber  12  or air entering the intermediate region  25  via the outside region  20  is avoided by the removal of the air by suction from the aforementioned regions to the suction side of the blower  31 . 
     In the second exemplary embodiment of the invention, shown in FIGS. 2 and 3, the apparatus  10   a  is embodied as a bottling system for liquid pharmaceuticals. The bottling is done into ampules  2 , but vials or the like can also be filled. The boxlike housing  11   a  can be seen, through which the ampules  2  are shunted at the level of the transport plane  41  in the transport direction  42  (which in FIG. 2 is perpendicular to the plane of the drawing). The entrance gate  15   a  is integrated with the housing  11   a  and has a partition  43  dividing it from the production chamber or insulator interior  12   a . Below the transport plane  41 , a suction grid  44  is provided, which defines a suction conduit  45 . Via the suction grid  44  and the suction conduit  45 , air is aspirated out of the region of the entrance gate  15   a  by means of the blower  31   a ; this air then reaches a partitioned-off interstice  46  above the isolator interior  12   a . A recirculating blower  47  is disposed in the interstice  46  and causes air to circulate in the isolator interior  12   a  via a clean-air filter  48 . 
     As can be seen from the flow arrows  49  in FIG. 2, the air from the entrance gate  15   a  is aspirated away essentially downward into the suction conduit  45 , and in the suction conduit  45 , in the peripheral region near the bottom of the housing  11   a , this air is deflected upward in the direction of the blower  31   a.    
     It can also be seen from FIG. 3 that air from the isolator interior  12   a  flows into the entrance gate  15   a  (flow arrow  50 ). This is because, analogously to the first exemplary embodiment of FIG. 1, a higher pressure prevails in the isolator interior  12   a  than in the entrance gate  15   a . The entry of contaminated air into the isolator interior  12   a  is prevented by this purposeful aspiration of the air out of the isolator interior  12   a , as in the first exemplary embodiment. 
     From the flow arrows  51  and  52 , it can also be seen that air either enters the entrance gate  15   a  from the outside region  20   a  or that air flows out of the entrance gate  15   a  into the outside region  20   a , depending on whether a higher air pressure prevails in the outside region  20   a  than in the entrance gate  15   a , or vice versa. 
     The entry of air from the outside region  20   a  into the entrance gate  15   a  prevents contaminated process air from escaping into the outside region  20   a , which is especially desirable in the case of toxic products. Conversely, if there is a purposeful outflow of air from the entrance gate  15   a  into the outside region  20   a , a purposeful pressure reduction in the isolator interior  12   a  compared to the outside region  20   a  can take place, so that less waste air, which would have to be replenished by compensatory fresh air, is generated by the apparatus  10   a . As a result, the energy demand of the apparatus  10   a  is reduced. 
     It will also be noted that the apparatus  10   a , as in the first exemplary embodiment, has an air flow corresponding to the entrance gate  15   a  or a corresponding construction on the outlet side of the apparatus  10   a  as well. In addition, the air flow in the isolator interior  12   a  is again embodied as a laminar air flow, but it flows around the ampules  2  essentially vertically from top to bottom. This kind of air guidance is already widely known in isolator technology, however. 
     The foregoing relates to preferred exemplary embodiments of the invention, it being understood that other variants and embodiments thereof are possible within the spirit and scope of the invention, the latter being defined by the appended claims.