Apparatus for Dispensing Powder

Abstract

A powder dispensing apparatus is disclosed in which the apparatus includes a drum assembly 2 . The drum assembly includes a support portion 10 and a foil 14 which are linearly movable relative to one another. The foil 14 has a plurality of through-apertures 25 , and the support portion 10 includes a corresponding number of apertures 20 . The base of each aperture 20 in the support portion is closed off by a piston 24 . The apertures 25, 20 are aligned at a filling position where powder can fill a compartment. The foil 14 is then translated relative to the support portion 10 in order to close the compartments. The drum 2 can be rotated through 180° to a dispensing position. The foil 14 is moved so that the apertures 25, 20 are aligned and the pistons 24 can be used to dispense powder into a receptacle.

1 . Apparatus for dispensing a defined quantity of powder material comprising a drum assembly having a foil and a support portion, wherein the foil has at least one through aperture, said support portion having at least one aperture, the aperture of the support portion being closable to define a compartment into which powder can be delivered at a filling position, and the drum assembly being movable to allow movement of the filled compartment to a dispensing position to allow the contents of the compartment to be dispensed,
 wherein the foil is movable relative to the support portion, and wherein the aperture in the support portion is arranged to be aligned with the through aperture in the foil at the filling position and at the dispensing position and wherein the aperture in the support portion is arranged to be misaligned with the through aperture in the foil between the filling position and the dispensing position so that the component is closed.   
     
     
         2 . Apparatus according to  claim 1  wherein the drum assembly is rotatable between the filling and dispensing positions. 
     
     
         3 . Apparatus according to  claim 1  wherein the foil has a plurality of linearly spaced apertures and the support portion has a corresponding number of linearly spaced apertures. 
     
     
         4 . Apparatus according to  claim 1  wherein the or each aperture of the support portion has an associated piston which can be moved into the inner end of the aperture. 
     
     
         5 . Apparatus according to  claim 4  wherein each piston is carried on a carrier. 
     
     
         6 . Apparatus according to  claim 5  wherein the carrier is cam operate to effect movement of said piston or pistons. 
     
     
         7 . Apparatus according to  claim 1  wherein said cylindrical portion and said support portion are moveable axially relative to another to cause opening or closing of said compartment. 
     
     
         8 . Apparatus according to  claim 1  wherein a receptacle or receptacles is located adjacent the dispensing position to receive dispensed powder. 
     
     
         9 . Apparatus according to  claim 4  wherein the or each piston is actuable at the dispensing position to cause it to move into said compartment to effect dispensing of said powder. 
     
     
         10 . Apparatus according to  claim 1  including a hopper containing powder for delivering to the or each compartment. 
     
     
         11 . Apparatus according to  claim 10  wherein the hopper includes means for compressing the powder towards the or each compartment. 
     
     
         12 . Apparatus according to  claim 11  wherein the compressing means includes a roller. 
     
     
         13 . Apparatus according to  claim 1  wherein the filling and dispensing positions are spaced apart by approximately 180°. 
     
     
         14 . Apparatus according to  claim 1  wherein the powder is a pharmaceutical powder for use as a dry powder inhaler. 
     
     
         15 . Apparatus according to  claim 4  wherein the position of the or each piston in its associated aperture is controllable to define the size of the compartment and thereby weight of the powder dose in the compartment. 
     
     
         16 . Apparatus according to  claim 4  wherein the or each piston is arranged to compact the powder in a closed compartment. 
     
     
         17 . Apparatus according to  claim 1  further including a cleaning station arranged to clean the support portion, wherein the cleaning station is located between the dispensing position and the filling position. 
     
     
         18 . Apparatus according to  claim 1  including a carriage on which the drum assembly is mounted, wherein the carriage permits translational movement of the drum assembly relative to a receptacle. 
     
     
         19 . A method of dispensing a defined quantity of powder material, the method comprising the steps of:
 positioning a foil relative to a support portion of a drum assembly so that at least one through aperture in the foil can be aligned with an aperture in the support portion;   filling a compartment in the support portion by delivering powder through the aperture of the foil and the aperture of the support portion;   moving the foil relative to the support portion in order to close the compartment;   moving the drum assembly so that the filled compartment can be moved to a dispensing position;   moving the foil relative to the support portion so that the at least one through aperture in the foil can be aligned with the aperture in the support portion; and   dispensing the contents of the compartment when it is in the dispensing position.   
     
     
         20 . An apparatus for dispensing a predetermined dose of powder, comprising:
 a drum assembly having a main axis and at least one aperture into which powder can be delivered at a filling position;   a piston associated with the or each aperture, wherein the piston defines the base of a compartment into which powder can be delivered, and wherein the piston is movable within the compartment;   a driving assembly that is connectable to the piston, wherein the driving assembly is arranged to drive the piston radially with respect to the main axis of the drum assembly to dispense powder out of the compartment, through the aperture;   wherein the drum assembly is rotatable from the filling position to a dispensing position, and wherein the driving assembly is located axially of the piston with respect to the main axis of the drum assembly.   
     
     
         21 . Apparatus according to  claim 20  comprising a plurality of pistons, each associated with a separate aperture. 
     
     
         22 . Apparatus according to  claim 20  further comprising an alignment adjuster for adjusting the inclination of the or each piston relative to its associated aperture. 
     
     
         23 . Apparatus according to  claim 20  wherein the radial movement of the or each piston is provided by the geared-down motion of a component in the drive assembly. 
     
     
         24 . Apparatus according to  claim 20  wherein the piston defines the base of a compartment into which powder can be delivered, and the position of the piston can be controlled in order to adjust the volume of the compartment. 
     
     
         25 . Apparatus according to  claim 24  wherein the piston is arranged to compress the powder in the compartment. 
     
     
         26 . Apparatus according to  claim 25  further including a compaction band against which the piston can compress the powder, wherein the compaction band is arranged to follow the motion of the compartment, at least in part, while it moves from the receiving position to the dispensing position. 
     
     
         27 . Apparatus according to  claim 20  wherein the drum assembly, the piston and the driving assembly are mounted on a carriage that permits translation of the components so that powder can be dispensed by the pistons while the drum assembly is translating. 
     
     
         28 . Apparatus according to  claim 20  wherein the drum assembly is supported by the drive assembly from one side only. 
     
     
         29 . A method of cleaning the apparatus of  claim 20  comprising the steps of:
 disconnecting the piston from the drive assembly; 
 removing the drum assembly from the drive assembly; 
 cleaning the drum assembly; and 
 re-attaching the drum assembly by connecting the piston and the drive assembly.