Apparatus and method of dispensing small quantities of particles

1. An apparatus for dispensing small quantities of particles, the apparatus comprising a hopper provided with a sieve at a bottom portion thereof, the hopper defining a powder-containing zone above the sieve which in use contains powder to be dispensed therefrom through the sieve, a support for the hopper, the support holding a portion of the hopper so that the hopper can in use be held above a container into which the dispensed powder is to be received, at least one actuator for delivering impact energy to the hopper for causing an amount of the powder to be dispensed through the sieve when the hopper receives the impact energy, and a deagglomeration device disposed in the powder-containing zone, wherein the deagglomeration device comprises at least one stirring device which is adapted to be movable when the impact energy from the at least one actuator is delivered to the hopper and wherein the stirring device comprises a bridge piece which is located on an upper peripheral rim of the hopper and a plurality of downwardly depending stirring elements, each stirring element having an upper end fixed to the bridge piece and a lower end located in the powder-containing zone.

2. An apparatus according to claim 1 wherein said each stirring element comprises a wire.

3. An apparatus according to claim 2 wherein each wire is selected to have a length and cross-section, and material of said each wire is selected to have a modulus of elasticity, so that when the hopper receives the impact energy from the at least one actuator, said each wire is caused to vibrate laterally.

4. An apparatus according to claim 2 wherein a mutual separation between the wires is less than a width of a hole of the sieve.

5. An apparatus according to claim 2 wherein a separation between the lower ends of the wires and the sieve is less than a width of a hole of the sieve.

6. An apparatus according to claim 1 wherein the bridge piece is removably located on the rim of the hopper and is adapted to be movable laterally relative to the rim.

7. An apparatus according to claim 6 wherein the bridge piece is provided with a downwardly-opening slot at each respective end thereof into which slots the rim of the hopper is received, with a width of the slots being greater than that of the rim.

8. An apparatus according to claim 6 wherein a weight of the bridge piece and the stirring elements is selected so that when the impact energy from the actuator impacts the hopper, the impact energy transmitted to the bridge piece from the upper peripheral rim of the hopper causes the bridge piece to jump vertically.

9. A method of dispensing small quantities of particles, the method comprising the steps of: disposing in a hopper provided with a sieve at a bottom portion thereof a powder to be dispensed therefrom through the sieve; deagglomerating the powder in the hopper by mechanically engaging the powder with a deagglomeration device disposed in a powder-containing zone located above the sieve; supporting the hopper by holding a portion of the hopper with a support so that the hopper is held above a container into which the dispensed powder is to be received; and delivering impact energy to the hopper by at least one actuator thereby to cause an amount of the powder to be dispensed through the sieve when the hopper receives the impact energy wherein the deagglomeration device comprises at least one stirring device which is adapted to be movable when the impact energy from the at least one actuator is delivered to the hopper, and in the delivering step the impact energy also causes movement of the at least one stirring device in the powder and wherein the stirring device comprises a bridge piece which is located on an upper peripheral rim of the hopper and a plurality of downwardly depending stirring elements, each stirring element having an upper end fixed to the bridge piece and a lower end located in the powder-containing zone.

10. A method according to claim 9 wherein said each stirring element comprises a wire.

11. A method according to claim 10 wherein each wire is selected to have a length and cross-section, and material of said each wire is selected to have a modulus of elasticity, so that when the hopper receives the impact energy from the at least one actuator, said each wire is caused to vibrate laterally.

12. A method according to claim 10 wherein a mutual separation between the wires is less than a width of a hole of the sieve.

13. A method according to claim 10 wherein a separation between the lower ends of the wires and the sieve is less than a width of a hole of the sieve.

14. A method according to claim 9 wherein the bridge piece is removably located on the rim of the hopper and is adapted to be movable laterally relative to the rim.

15. A method according to claim 14 wherein the bridge piece is provided with a downwardly-opening slot at each respective end thereof into which slots the rim of the hopper is received, with a width of the slots being greater than that of the rim.

16. A method according to claim 14 wherein a weight of the bridge piece and the stirring elements is selected so that when the impact energy from the actuator impacts the hopper, the impact energy transmitted to the bridge piece from the upper peripheral rim of the hopper causes the bridge piece to jump vertically.