Checkweigher for checking the weight of filled receptacles
A checkweigher ( 10 ) for measuring the weight of a pre-metered dose of medicament in a pharmaceutical blister ( 12 ) is provided. The checkweigher comprises a rotatable blister support element ( 14 ) for supporting a plurality of blisters ( 12 ), an evacuation assembly ( 16 ) for sequentially accessing and removing the contents of the plurality of blisters ( 12 ) as the blister support element rotates, a load sensor ( 18 ) for weighing the blister support element ( 14 ) and the plurality of blisters ( 12 ), drive means ( 20 ) for moving the blister support element ( 14 ) to and from the load sensor ( 18 ), and a controller ( 22 ) for controlling the drive means ( 20 ). The plurality of blisters ( 12 ) may be provided as single blister units or as part of a blister pack.
1. A receptacle checkweigher comprising:
a frame which holds a support surface;
a moveable spindle having a plurality of recesses arranged to hold filled receptacles, the spindle connected to said support surface;
a weighing device;
a spindle drive motor operable to produce rotation of the spindle; and
an evacuation assembly operable to remove powder from the receptacles;
wherein the weighing device is configured to weigh the spindle and the plurality of receptacles together.
2. A receptacle checkweigher according to claim 1 wherein the spindle is arranged to hold a plurality of capsules.
3. A receptacle checkweigher according to claim 1 wherein the spindle is arranged to hold a plurality of blister strips.
4. A receptacle checkweigher as claimed in claim 3 , in which the spindle is adapted to support a blister strip around a peripheral extent thereof.
5. A receptacle checkweigher as claimed in claim 4 , in which the spindle comprises a plurality of recesses for receiving the blister strip, each blister of the blister strip nestably coupling with one of said recesses in use.
6. A receptacle checkweigher according to claim 1 wherein the spindle is arranged to hold a plurality of blister strips containing capsules.
7. A receptacle checkweigher according to claim 1 wherein the spindle is arranged to hold a plurality of blister cartridges.
8. A receptacle checkweigher according to claim 1 wherein the evacuation assembly comprises a piercing element.
9. A receptacle checkweigher according to claim 8 wherein the piercing element comprises a primary evacuation orifice.
10. A receptacle checkweigher according to claim 9 wherein the piercing element comprises a secondary evacuation orifice.
11. A receptacle checkweigher according to claim 1 , wherein the spindle is arranged to dissipate static charge.
12. A receptacle checkweigher according to claim 11 , wherein the spindle comprises a conducting strip.
13. A receptacle checkweigher according to claim 1 wherein the spindle comprises a blister strip wound around the spindle in a helix.
14. A receptacle checkweigher according to claim 1 , wherein the checkweigher is arranged to measure the weight of a pre-metered dose of medicament in a blister, the checkweigher further comprising drive means operable to move the spindle to and from the weighing device, and a controller operable to control the drive means.
15. A receptacle checkweigher as claimed in claim 1 , the evacuation assembly comprising a piercing station operable to piercably access the contents of each receptacle.
16. A receptacle checkweigher as claimed in claim 15 , in which the piercing station comprises a piercing head having a piercing element and an evacuation orifice.
17. A receptacle checkweigher as claimed in claim 16 , in which the piercing element is tubular and has a pointed peripheral edge at an open end thereof.
18. A receptacle checkweigher as claimed in claim 16 , in which the piercing element and the evacuation orifice are provided coaxially with each other on the piercing head.
19. A receptacle checkweigher as claimed in claim 16 , in which the piercing head comprises a further piercing element and a further said evacuation orifice.
20. A receptacle checkweigher as claimed in claim 16 , in which the piercing element is cylindrical and is closed at one end by a planar piercing surface.
21. A receptacle checkweigher as claimed in claim 1 , in which at least a portion of the evacuation means is moveable relative to the spindle.
22. A receptacle checkweigher comprising:
a frame which holds a support surface;
a moveable spindle having a plurality of recesses arranged to hold filled receptacles, the spindle connected to said support surface;
a weighing device operable to weigh the spindle and the plurality of receptacles;
a spindle drive motor operable to produce rotation of the spindle; and
an evacuation assembly operable to remove powder from the receptacle;
the receptacle checkweigher further comprising drive means operable to move the spindle to and from the weighing device, and a controller operable to control the drive means.
23. A receptacle checkweigher as claimed in claim 22 , wherein the receptacle checkweigher is operable to measure the weight of a pre-metered dose of medicament in a blister.