Abstract:
A powder dispensing device is disclosed for dispensing powder into hard gelatin capsules or the like. The powder dispensing device comprises at least one plunger for compacting the powder to a powder compact and/or at least one transfer plunger which transfers the previously produced powder compact into a capsule part ready to be filled. The device includes a sensing apparatus including fiber-optical cables and a lens for introducing and receiving radiation passed through the powder or the powder compact. The sensing apparatus is connected to either the compacting plunger or the transfer plunger, or both.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a 35 USC 371 application of PCT/EP 2006/064575 filed on Jul. 24, 2006. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to a sensing apparatus, in particular in dispensing powder into hard gelatin capsules or the like. 
     2. Description of the Prior Art 
     From German Patent DE 100 01 068 C1, a dispensing device is known, which includes an incrementally rotated dispensing disk in the base of which boards are embodied which cooperate with stuffing dies that are movable up and down. The stuffing dies are disposed on a common stuffing die holder, and as they dip into the bores they press the powder into powder metal compacts. To detect spring breakage and to be able to draw a conclusion about the mass of the compacts, means are provided that detect the spring travel of the expulsion die at the immediately preceding stuffing die. In one exemplary embodiment, the stuffing dies directly preceding the expulsion dies are each provided with a travel pickup—such as a strain gauge or an inductive sensor. Thus both spring breakage and incorrect dosages can be detected. 
     SUMMARY OF THE INVENTION 
     The sensing apparatus of the invention has the advantage over the prior art that a qualitative conclusion is possible about such product parameters as the proportion of an active ingredient, quantitative quantity of an active ingredient, or product quantity. Thus product analysis of the compacts is made possible in a simple way; until now, this was done outside the apparatus by means of an analysis device. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a longitudinal section through a powder dispensing apparatus having sensing apparatus according to the invention; 
         FIG. 2  shows a simplified view of the powder dispensing device with the sensing apparatus according to the invention; and 
         FIG. 3  shows a more-precise schematic illustration of the components of the sensing apparatus. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The powder dispensing device  10  shown in  FIG. 1  for dosing and dispensing powder into hard gelatine capsules  1  or the like has a product container  11 . The product container  1  is formed by a jacket  12 , a cap  13 , and a dispensing disk  14 . At the level of the dispensing disk  14 , the product container  11  is surrounded by a ring  15 , which serves to receive upper parts  2  of capsules. Below the ring  15  segments  17  are provided which are correspondingly embodied to receive lower parts  3  of capsules. The segments  17  are each supported pivotably about a bolt, not shown, that is secured in the ring  15 , and upon circulating through a fixed curve  20 , via a curve roller  21 , are moved inward, that is, below bores  22  in the dispensing disk  14 , or outward, that is, beyond the circumference of the ring  15 , depending on requirements. The dispensing disk  14  is secured to a shaft  23  that is coupled to the drive of the device  10  and that rotates the dispensing disk  14  in increments of one angular amount each. 
     For fastening the curve  20 , a second ring  24  is provided, which in turn is fastened to the tabletop  25  of the device  10 . Between the curve  20  and the dispensing disk  14 , an intermediate ring  26  is provided, which can be pressed by adjusting means, not shown, against the underside of the dispensing disk  14 . This intermediate ring  26  serves to seal off the bores  22  in the dispensing disk  14  in the region where the powder is dispensed. 
     As  FIG. 1  also shows, above the product container  11  is a holder  28 , which is movable up and down by means of columns  27  and in each case executes a defined stroke. Along an arc of the holder  28 , a plurality of stuffing die holders  29 , for instance three stuffing die holders  29 , are disposed at equal angular spacings, and in each of them five stuffing dies  30  are guided that penetrate the cap  13  of the product container  11  in corresponding bores. Expulsion dies or transfer dies  31  are also located on the holder  28  and are connected, in a height-adjustable manner, to a mount  32  disposed on the holder  28 . The transfer dies  31  are surrounded inside the product container  11  by a powder-repellent body  33 . A sensor  35  is disposed in the tip of the transfer die  31 , for detecting such product parameters as the active ingredient proportion, quantitative active ingredient quantity, or product quantity. The sensor  35  is preferably embodied optically (infrared). A fiber-optical line  37  is disposed in a recess in the transfer die  31 , so as to deliver the optical signal of the sensor  35  to a signal evaluator  39 . 
     The device  10  described above functions as follows: For forming the compacts in the bores  22  from the powder located in the product container  11 , the dispensing disk  14  is rotated clockwise in increments, in each case beneath the stuffing dies  30  of one stuffing die holder  29 . Next, the stuffing dies  30 , upon a downward motion of the holder  28 , penetrate the bores  22  of the dispensing disk  14 , and the powder located in the bore  22  is compacted. During the compacting or pressing of the powder, the intermediate ring  26  forms a counterpart bearing for the stuffing dies  30  or powder. Next, the stuffing dies  30  are moved back out of the bores  22  of the dispensing disk  14  by means of the holder  28 , whereupon the dispensing disk  14  is rotated into the vicinity of the next stuffing die holder  29 . After the final pressing operation, the thus-formed compacts reach the vicinity of the transfer dies  31 , where they are inserted into the lower capsule parts  3  furnished by means of the segments  17 . Next, the lower capsule parts  3  are rejoined to the upper capsule parts  2 . 
     In  FIG. 2 , a powder dispensing device based on the tubule principle, with a sensor array, is shown as an example. The stuffing die  30 , comprising a cylinder  40  (or tubule) and a piston  36 , is lowered into a rotary container  38  as far as the level of the product, this level being set (manually or by means of an actuator), via the segment containers. Next, the cylinder  40  is lowered into the product layer, while the piston  36  maintains its own position and forms the dosage chamber  42 , set simultaneously beforehand to all dosages. The thus-set dispenser is lowered to the bottom of the rotary container  38 , until the dosage chamber  42  is full. If necessary for the product in question, the desired compacting can now be done via the setting of the special cam (manually or by means of an actuator). The sensing can then preferably be done for further evaluation and determination of the product parameters of interest. After that, the piston  36  moves upward and is raised somewhat from the blank or compact. Next, the dispenser is raised above the rotary container  38  again and is oriented vertically with the lower capsule parts in the bushes. Next, the piston is lowered, and the product is introduced into the lower capsule part  3 . This is followed by a new dispensing cycle. 
       FIG. 3  in a more precise view now shows the basic construction of the sensing apparatus in section. In the stuffing die  30  or transfer die  31 , the powder repellant body  33  is preferably a cylindrical recess provided in the middle thereof which extends in the direction of the axis of the die  30 ,  31  and ends in an opening in the tip of the die  30 ,  31 . Two fiber-optical cables  37  are disposed in the recess. One fiber-optical cable  37  is connected to an optical transmitter  43 ; the other fiber-optical cable  37  is connected to an optical receiver  45 . The optical transmitter  43  and optical receiver  45  are integrated in a signal detector  39 , which is preferably equipped with triggering electronics and a triggering unit. The signal detector  39  is preferably located at a point remote from the dies  30 ,  31 . The fiber-optical cables  37  conduct optical radiation into the product and receive the radiation, reflected by the product, via a lens  41 . The lens  41  is preferably disposed in or at the opening in the die  30 ,  31 . 
     As the lens  41 , a convex lens is preferably employed. This produces a focal point  47  that is located inside the compact but not on its surface. As a result, dirt on the lens  41  does not in principle impair the quality of signal detection. The signal detector  39  initiates a measurement operation when the die  30 ,  31  reaches a defined position within a processing step. The optical transmitter  43  is then triggered in such a way that for a defined length of time, it outputs optical radiation to one of the glass fibers  37 . This radiation, via the fiber-optical cables  37  and the lens  41 , penetrates the product, such as the powder metal compact. The product reflects a portion of the introduced radiation. Via the lens  41  and the second fiber-optical cables  37 , the reflected radiation reaches the optical receiver  45 , which converts the optical signals into electrical signals. The signal detector  39  now assesses the signals received, as a function of the signals transmitted. Known methods of spectral analysis are employed, in which the wave spectra of the radiation received are evaluated. Qualitative conclusions about such product parameters as the active ingredient proportion, quantitative active ingredient quantity, or product quantity are thus made possible. Preferably, radiation in the infrared range is emitted. 
     Instead of carrying signals in and out by means of fiber-optical cables  37 , transmitters  43  and receivers  45  could already be disposed in the die  30 ,  31 , and the signals could be exchanged with the signal processor  39  in some other way, for instance electrically or in wireless fashion. 
     The foregoing relates to the 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.