Claims:We claim
1. A machine for filling pellets in capsules, including a pellet turret comprising a cylindrical pellet dosing chamber disposed for rotation about a first vertical axis and about a plurality of pellet dosing stations and an ejection station located equidistantly around the first vertical axis cyclically and intermittently at intervals, a top cover for the dosing chamber and a pellet feed means communicating with the dosing chamber, wherein the dosing chamber comprises a plurality of dosing chamber sectors disposed side by side and mounted for rotation about the first vertical axis together and for guided up and down movement relative to one another about the first vertical axis, each of the dosing chamber sectors having atleast one row of main dosage metering passages transversely extending therethrough and a radially displaceable bottom sector plate located underneath the dosing chamber sector and having atleast one row of complementary dosage metering passages extending transversely therethrough matching in position and size with the main dosage metering passages in the dosing chamber sector and wherein the pellet turret comprises a differential drive cum displacement mechanism configured to rotate the dosing chamber cyclically and intermittently at intervals about the first vertical axis and to move up the dosing chamber sectors progressively from the ejection station upto the end dosing station and to move down a dosing chamber sector from the end dosing station to the ejection station about the first vertical axis and to align the complementary dosage metering passages in a bottom sector plate with the main dosage metering passages in the corresponding dosing chamber sector and then to misalign the complementary dosage metering passages in the bottom sector plate with the main dosage metering passages in the corresponding dosing chamber sector at the ejection station in a cycle of operation of the dosing chamber and a piston assembly mounted at the ejection station to push down dosages of pellets in the main dosage metering passages in a dosing chamber sector through the complementary dosage metering passages in the corresponding bottom sector plate aligned with the main dosage metering passages in the dosing chamber sector at the ejection station.

2. The machine as claimed in claim 1, wherein the differential drive cum displacement mechanism comprises a stepped diameter spindle disposed for rotation about the first vertical axis cyclically and intermittently at intervals and having a large diameter portion and a narrow diameter portion, a stationary upright cylindrical main cam body disposed over the narrow diameter portion and having a main cam groove around the main cam body and a plurality of support blocks disposed around the main cam body corresponding to the number of dosing chamber sectors, each of the support blocks being disposed below each of the dosing chamber sectors and having a main cam follower fixed at the center of the inner side thereof and slidably engaged in the main cam groove, each of the support blocks being mounted at the inner side thereof to the bottom of the large diameter portion for guided up and down movement with respect to the large diameter portion, each of the support blocks having a pair of upright bosses at the outer side thereof, each upright boss being equidistantly spaced from the center of the support block, the trajectory and geometry of the main cam groove being configured and profiled to allow the main cam followers with the support blocks and dosing chamber sectors to rotate about the main cam groove and to move up relative to one another from the ejection station upto the end dosing station and to move down a main cam follower and the corresponding support block and dosing chamber sector from the end dosing station to the ejection station, a rail horizontally disposed at the center of the top surface of each support block between the respective upright bosses and fixed thereto, a channel slide horizontally slidably engaged over the rail, a vertically displaceable member disposed over the outer side of each support block between the upright bosses of the support block through a slot in the vertically displaceable member and having an inwardly projecting top sidewall disposed over the channel slide and mounted thereto and an inwardly projecting bottom sidewall engaged over the bottom surface of the support block and having a V-shaped notch and a vertically displaceable actuator disposed at the ejection station in the rotary path of the support blocks carrying the vertically displaceable members and dosing chamber sectors and profiled to releasably engage in the V-shaped notch of a vertically displaceable member at the ejection station and oscillator means to displace the actuator and the vertically displaceable member at the ejection station in opposite directions radially with respect to the dosing chamber sectors at the ejection station and thereby align the complimentary dosage metering passages in the corresponding bottom sector plate with the main dosage metering passages in the corresponding dosing chamber sector and then to misalign the complimentary dosage metering passages in the bottom sector plate with the main dosage metering passages in the dosing chamber sector and wherein each of the dosing chamber sectors comprises a base portion having an inner side in sliding contact with the large diameter portion, an outer side having an upstanding wall and a flat bottom surface, the base portion having a row of main dosage metering passages extending transversely therethrough, each of the dosing chamber sectors being fixed to each pair of upright bosses at the base portion thereof and wherein each of the bottom sector plates comprises a T-shaped plate having a cross limb and a perpendicular limb, the cross limb being disposed underneath the base portion of each of the dosing chamber sectors and having a row of complementary dosage metering passages and the perpendicular limb being disposed between each pair of upright bosses over the top side wall of each vertically displaceable member and mounted thereto.

3. A machine for filling pellets in capsules, including a pellet turret comprising a cylindrical pellet dosing chamber disposed for rotation about a first vertical axis and about a plurality of pellet dosing stations and an ejection station located equidistantly around the first vertical axis cyclically and intermittently at intervals, a top cover for the dosing chamber and a pellet feed means communicating with the dosing chamber, wherein the dosing chamber comprises a plurality of dosing chamber sectors disposed side by side and mounted for rotation about the first vertical axis together and for guided up and down movement relative to one another about the first vertical axis, each of the dosing chamber sectors having atleast one row of main dosage metering passages transversely extending therethrough, a dosage volume adjustment means and a radially displaceable bottom sector plate located underneath the dosing chamber sector and having atleast one row of complementary dosage metering passages extending transversely therethrough matching in position and size with the main dosage metering passages in the dosing chamber sector and wherein the pellet turret comprises a differential drive cum displacement mechanism configured to rotate the dosing chamber cyclically and intermittently at intervals about the first vertical axis and to move up the dosing chamber sectors progressively from the ejection station upto the end dosing station and to move down a dosing chamber sector from the end dosing station to the ejection station about the first vertical axis and to align the complementary dosage metering passages in a bottom sector plate with the main dosage metering passages in the corresponding dosing chamber sector and then to misalign the complementary dosage metering passages in the bottom sector plate with the corresponding main dosage metering passages in the dosing chamber sector at the ejection station in a cycle of operation of the dosing chamber and a piston assembly mounted at the ejection station to push down dosages of pellets in the main dosage metering passages in a dosing chamber sector through the complementary dosage metering passages in the corresponding bottom sector plate aligned with the main dosage metering passages in the dosing chamber sector at the ejection station.

4. The machine as claimed in claim 3, wherein the differential drive cum displacement mechanism comprises a stepped diameter spindle disposed for rotation about the first vertical axis cyclically and intermittently at intervals and having a large diameter portion and a narrow diameter portion, a stationary upright cylindrical main cam body disposed over the narrow diameter portion and having a main cam groove around the main cam body and a plurality of support blocks disposed around the main cam body corresponding to the number of dosing chamber sectors, each of the support blocks being disposed underneath each of the dosing chamber sectors and having a main cam follower fixed at the center of the inner side thereof and slidably engaged in the main cam groove, each of the support blocks being mounted at the inner side thereof to the bottom of the large diameter portion for guided up and down movement with respect to the large diameter portion, each of the support blocks having a pair of upright bosses at the outer side thereof, each upright boss being equidistantly spaced from the center of the support block, the trajectory and geometry of the main cam groove being configured and profiled to allow the main cam followers with the support blocks and dosing chamber sectors to rotate about the main cam groove and to move up relative to one another from the ejection station upto the end dosing station and to move down a main cam follower and the corresponding support block and dosing chamber sector from the end dosing station to the ejection station, a rail horizontally disposed at the center of the top surface of each support block between the respective upright bosses and fixed thereto, a channel slide horizontally slidably engaged over the rail, a vertically displaceable member disposed over the outer side of each support block between the upright bosses of the support block through a slot in the vertically displaceable member and having an inwardly projecting top sidewall disposed over the channel slide and mounted thereto and an inwardly projecting bottom sidewall engaged over the bottom surface of the support block and having a V-shaped notch and a vertically displaceable actuator disposed at the ejection station in the rotary path of the support blocks carrying the vertically displaceable members and dosing chamber sectors and profiled to releasably engage in the V-shaped notch of a vertically displaceable member at the ejection station and oscillator means to displace the actuator and the vertically displaceable member at the ejection station in opposite directions radially with respect to the dosing chamber sectors at the ejection station and thereby align the complimentary dosage metering passages in the corresponding bottom sector plate with the main dosage metering passages in the corresponding dosing chamber sector and then to misalign the complimentary dosage metering passages in the bottom sector plate with the main dosage metering passages in the dosing chamber sector and wherein each of the dosing chamber sectors comprises a base portion having an inner side in sliding contact with the large diameter portion, an outer side having an upstanding wall and a flat bottom surface, the base portion having a row of main dosage metering passages extending transversely therethrough, the dosage volume adjustment means comprises a vertically adjustable section plate sized to sit on a base portion and having a row of supplementary dosage metering passages transversely extending therethrough registering in size and position with the main dosage metering passages in the base portion and a row of open ended removable dosing bushes, each bush extending through each of the supplementary dosage metering passages in the section plate and corresponding main dosage metering passages in the dosing chamber sector, each of the dosing chamber sectors being fixed to each pair of upright bosses at the base portion thereof and wherein each of the bottom sector plates comprises a T-shaped plate having a cross limb and a perpendicular limb, the cross limb being disposed underneath the base portion of each of the dosing chamber sectors and having a row of complementary dosage metering passages and the perpendicular limb being disposed between each pair of upright bosses over the top side wall of each vertically displaceable member and mounted thereto.

5. The machine as claimed in claim 2 or 4, wherein the oscillator means comprises a fulcrum pin mounted for oscillation about a second vertical axis at the ejection station in the proximity of and parallel to the first vertical axis of rotation of the stepped diameter spindle, an upper oscillator arm horizontally disposed and having one end fixed to the top end of the fulcrum pin and the other end fixed to the actuator, a lower oscillator arm disposed horizontally and parallel to the upper oscillator arm and having one end fixed to the bottom end of the fulcrum pin and the other end fixed to an auxiliary cam follower engaged in an auxiliary cam groove in an auxiliary cam body mounted to a shaft disposed for rotation about a third vertical axis, the shaft being in the proximity of and parallel to the second vertical axis of oscillation of the fulcrum pin, the trajectory and geometry of the auxiliary cam groove being configured and profiled to cause the auxiliary cam follower to describe an oscillatory motion in the horizontal plane and to cause the fulcrum pin and the oscillator arms to describe an oscillatory motion in the horizontal plane and displace the actuator in opposite directions radially with respect to the dosing chamber sectors.

6. The machine as claimed in claim 1 or 3, wherein the top cover comprises a flat rim having a center opening with a stepped sidewall and a circular cover member projecting down from the bottom surface of the flat rim over the top portion of the pellet dosing chamber and a lid having a complementary stepped outer surface removably sitting against the stepped sidewall of the center opening in the flat rim and wherein the pellet feed means comprises a pellet feed tube extending into the pellet dosing chamber through the flat rim.

7. The machine as claimed in claim 1 or 3, wherein the piston assembly at the ejection station comprises a row of pistons corresponding to a row of main dosage metering passages in a dosing chamber sector and a row of complementary dosage metering passages in a bottom sector plate matching in position with the row of main dosage metering passages and the row of complementary dosage metering passages, the pistons being mounted in a horizontally disposed piston mounting plate and supported for guided up and down movement into and out of the pellet dosing chamber through a row of openings in the top cover of the pellet dosing chamber, the pistons having narrow tips sized to enter the main dosage metering passages in a dosing chamber sector and the complementary dosage metering passages in the corresponding bottom sector plate at the ejection station.

8. The machine as claimed in claim 7, wherein the piston assembly comprises a vibrator capable of generating vibrations in the vertical plane in a narrow amplitude range of 20 – 60 microns connected to the piston mounting plate.

9. The machine as claimed in claim 8, wherein the vibrator consists of an ultrasonic vibrator.

10. The machine as claimed in claim 1 or 3, which comprises a flexible material scraper blade extending down into the pellet dosing chamber from the top cover upto the main dosage metering passages in a dosing chamber sector and positioned between the ejection station and the end pellet dosing station.

11. The machine as claimed in claim 4, wherein the base portion of each dosing chamber sector consists of a recess and the one row of main dosage metering passages extend transversely through the recess and wherein the section plate is sized to sit in the recess.

12. The machine as claimed in claim 11, wherein the section plate comprises a bolt hole at the inner side centre thereof and the section plate is vertically adjustable in the recess with a bolt extending down through the bolt hole in thread engagement with the bolt hole and rotatably held in position to the base portion, the section plate being locked in position with a check nut tightened on the bolt against the section plate.
, Description:FIELD OF THE INVENTION
This invention relates to a machine for filling pellets in capsules.

BACKGROUND OF THE INVENTION
In the encapsulation industry, pharmaceutical industry in particular, pharmaceutical and neutraceutical products and food supplements in solid forms such as powder, granules, pellets and microtablets are often made into compact dosages by volumetric filling of the solids in capsules. This helps to maintain uniformity of the dosages and to prevent spillage and wastage and to help easy and convenient oral administration of the dosages. Various machines are known and reported for volumetric filling of capsules with pharmaceuticals in solid forms.

An apparatus for metering and discharging measured quantity of dry particulate material into capsules, comprises a metering device comprising an elongated metering member supported on a supporting member and having one or more generally cylindrical transversely extended metering chambers. The elongated metering member with the metering chambers is slidable on the supporting member. The metering chambers are movable to a first position to receive the particulate material and to a second position to discharge the particulate material into capsule bodies being formed (British Patent No 1089747).

In the above apparatus, during the sliding movement of the metering chambers against the supporting member, the particulate material may get crushed and damaged between the supporting member and the metering chambers. This will cause loss of the material and dust generation. This will also cause weight and dosage variations and reduce the reliability of the apparatus. The particulate material may also clog the clearance between the metering chambers and supporting member and obstruct the smooth sliding movement of the metering chambers against the supporting member.

Another apparatus for volumetric filling of products such as powder or granules in capsules, comprises a metering disc rotatable about a vertical axis and having groups of rows of metering chambers (through passages extending transversely through the metering disc) on a pitch circle. Pushers are displacebly supported underside of the metering disc to close the metering chambers in the filling position of the apparatus and to open the metering chambers in the ejection or evacuation position of the apparatus. The product in the metering chambers is dispensed into capsule bodies with their mouths directed upwards held below the metering chambers (US 6286567B1).

The metering disc of the above apparatus consists of a plain upper surface, because of which the product flow on the metering disc into the metering chambers is slow and non-uniform. There is also possibility that the product will bridge on the metering disc and cause slow and non-uniform movement of the product on the metering disc resulting in the slow and non-uniform filling of the product in the metering chambers. Discharge of the product from the metering chambers into the capsule bodies will also slow down thereby reducing productivity. Non-uniform filling of the capsules will cause weight and dosage variations and reduce the reliability of the apparatus.

A machine for filling capsules with pharmaceutical material particles, in particular microtablets, comprises a rotary carousel having a plurality of slide units for holding and handing the capsules. The machine also comprises a series of hollow conduits uniformly distributed on a disc like element mounted on the carousel and a hopper. A roller is partly immersed in the pharmaceutical material mass contained in the hopper. The roller consists of a plurality of suction recesses for accommodating and retaining a predetermined quantity of the particles drawn from the hopper and then releasing the particles into the capsule bodies via the hollow conduits mounted on the carousel (WO2007/012966 A1).

In the above machine, the pharmaceutical material in the suction recesses on the roller gets transferred into the capsule bodies through the hollow conduits in the disc. Since the pharmaceutical material does not get transferred into the capsule bodies directly from the suction recesses on the roller, there will be delay in the capsule bodies getting filled with the pharmaceutical material and reduction in productivity. There is also a possibility that the entire particles in the hollow conduits may not get transferred into the capsule bodies thereby causing weight and dosage variations and reducing reliability of the machine.

A device for filling capsules with pellets comprises atleast one dosing chamber to receive the pellets and to discharge the pellets into capsule bodies positioned below the dosing chamber. The device also comprises mechanical means to apply a force on the pellets and fill the dosing chamber with the pellets. A slide gate valve operates to open the dosing chamber and discharge the pellets into the capsule bodies and to close the dosing chamber. Closing and opening of the dosing chamber is carried out by dragging the gate valve horizontally (WO 2007/062980 A1).

While the gate valve of the above device is being dragged, the pellets may get crushed and damaged between the dosing chamber and gate valve. This will not only result in material loss and dust generation but will also create weight and dosage variations and reduce the reliability of the device. The pellets may also clog the clearance between the dosing chamber and gate valve and obstruct the smooth movement of the gate valve

A machine for metering microtablets into capsules, comprises a metering surface subjected to vibration and rotation about a vertical axis. The metering surface comprises a number of sloping surfaces and open pockets at the top of the sloping surfaces. The microtablets travel upwards along the sloping surfaces and enter the respective pockets. The machine also comprises an unloading device cooperating with the metering surface and comprising a cam member. A supporting plate is located beneath the cam member to support the microtablets dropping out of the open pockets and to guide the microtablets into capsule bodies. A catch bin collects the microtablets sliding off the supporting plate and away from the capsules bodies (US2007/0144674A1).

In such a machine, there is a possibility that the microtablets may miss the catch bin (may either overshoot the catch bin or may not reach the catch bin) thereby causing material loss and wastage.

A machine for filling capsules with pellets comprises a feeding chamber communicating with a hopper at the top thereof and having a feeding jaw mechanism at the bottom thereof. The jaw mechanism comprises a fixed jaw member and a pair of moving jaw members at opposite sides of the fixed jaw member. In the closed position of the fixed jaw member and the moving jaw members, open spaces or cavities are formed between pairs of teeth of the fixed jaw member and corresponding teeth of the moving jaw members disposed between the pairs of teeth of the fixed jaw member. The open spaces or cavities form the metering chambers for the pellets. Capsule bodies are positioned below the metering chambers to receive the pellets. The metering chambers are opened and closed by closing and opening plates at the top and bottom of the fixed jaw member. The top and bottom plates slide onto and away from the fixed jaw member to close and open the metering chambers.

During the sliding movement of the top and bottom plates of the above machine, the pellets may get crushed and damaged between the fixed jaw member and top and bottom plates. This will cause material loss and dust formation. This will also cause weight and dosage variations and reduce the reliability of the machine. Besides, the pellets may clog the clearance between the fixed jaw member and the top and bottom plates and obstruct the smooth sliding movement of the top and bottom plates against the fixed jaw member.

A machine for filling capsules with powder comprises a tamping turret and a capsule turret disposed adjacent to each other for rotation about vertical axes cyclically and intermittently at intervals in the same direction. The tamping turret comprises a dosing disc rotatably held on the respective vertical axis at the bottom of a dosing chamber. The dosing disc is rotatable about a plurality of tamping stations and an ejection station located equidistantly around the periphery of the dosing disc. The dosing disc comprises a plurality of rows of through vertical passages extending transversely through the periphery of the dosing disc on a pitch circle (metering chambers). A plurality of tamping pistons corresponding to the rows of vertical passages are disposed in the dosing chamber in the same lay out as the vertical passages for up and down movement in the dosing chamber. The pistons at the tamping stations are disposed for progressively increasing the strokes thereof.

The capsule turret comprises a capsule carrier disc rotatably held on the respective vertical axis. The capsule carrier disc is rotatable about a plurality of capsule handling stations located equidistantly around the periphery of the capsule carrier disc including a capsule filling station. The capsule carrier disc comprises a plurality of rows of capsule holding grooves extending transversely through the periphery of the capsule carrier disc on a pitch circle in the same layout as the rows of vertical passages in the dosing disc.

During the cyclic operation of the machine, powder flowing into the rows of vertical passages in the dosing disc at the tamping stations are progressively compacted into the required dosages by the respective pistons moving down into the rows of vertical passages. A bottom support plate with an interrupted portion (part annulus) is disposed below the dosing disc so as to close the vertical passages in the dosing disc from the bottom thereof at the tamping stations. The interrupted portion in the bottom support plate corresponds to the ejection station. The intermittent rotational movement of the dosing disc and capsule carrier disc is synchronised such that at the ejection station, compacted dosages of the powder in the vertical passages in the dosing disc is pushed out of the vertical passages by the respective pistons moving down into the vertical passages and the dosages expelled from the vertical passages at the ejection station enter the capsule bodies held in the corresponding vertical grooves in the capsule carrier disc positioned below the vertical passages at the capsule filling station.

The above machine for filling capsules with powder cannot be used for filling pellets in capsules in that the pellets do not require compaction with pistons and will get damaged during the tamping operations by the pistons.

A machine for filling capsules with pellets, comprises a pellet turret having a dosing chamber fitted with a dosing disc at the bottom thereof. The dosing disc is mounted for cyclic and intermittent rotation about a vertical axis around a plurality of dosing stations and an ejection station located equidistantly around the periphery of the dosing disc. The dosing disc comprises a top cover and an inner bottom surface tapered from the centre to the periphery thereof. The dosing disc also comprises a plurality of rows of through vertical passages extending transversely through the periphery thereof on a pitch circle to form metering chambers.

A sector plate is fixedly held above the ejection station. The sector plate comprises a perforated portion overlying the ejection station and having perforations matching with the corresponding row of vertical passages at the ejection station and a non-perforated portion overlying an immediately following dosing station. A row of air jet nozzles are disposed above the ejection station in the same layout as the rows of vertical passages in the dosing disc. The air jet nozzles are connected to an air chamber and are disposed for intermittent up and down movement. The airjet nozzles extend into the dosing chamber through the top cover thereof and the perforations in the sector plate to blow air into a row of vertical passages filled with pellets at the ejection station.

A circumferentially displaceable bottom support plate is located below the dosing disc in sliding contact therewith. The bottom support plate comprises a discharge opening and a vacuum chamber circumferentially spaced from each other. The bottom support plate is disposed for oscillatory movement in the horizontal plane circumferentially underneath the dosing disc to allow the discharge opening and vacuum chamber in the bottom support plate to align and misalign with the metering chambers at the ejection station and an adjoining dosing station intermittently.

The machine includes a sweeping brush depending down from the top cover of the dosing chamber and sliding against the dosing disc and an air blower fixedly held above the dosing disc at the leading end of the dosing station preceding the ejection station in order to facilitate uniform filling of the pellets in the vertical passages. The machine also includes pellet feeder means located above the dosing chamber and comprising a vibratory feeder tray mounted at the top of the pellet turret frame and a chute fixed to the pellet turret frame and communicating with the vibratory feeder tray and the dosing chamber.

The machine further comprises a capsule turret disposed adjacent to the pellet turret and cyclically and intermittently rotatable about a vertical axis around a plurality of capsule handling stations located equidistantly around the periphery thereof including a capsule filling station. The capsule turret comprises a capsule carrier disc having plurality of capsule handling units in the same lay out as the rows of vertical passages in the dosing disc.

The intermittent rotation of the pellet turret and capsule turret is synchronised such that in each cycle of operation of the machine, the dosing disc with a row of vertical passages filled with dosages of pellets is positioned at the ejection station of the pellet turret and the capsule carrier disc with a capsule handling unit having capsule bodies with their mouths directed upwards is positioned at the capsule filling station of the capsule turret below the ejection station. The bottom support plate oscillates circumferentially underneath the dosing disc to align the discharge opening therein with the vertical passages in the dosing disc containing the dosages of pellets. The air jet nozzles at the ejection station blow air into the vertical passages to push the doses of pellets in the vertical passages out into the capsule bodies via the discharge opening in the bottom support plate (patent application No 52/MUM/2008 filed on 7 January 2008).

In the above pellet filling machine, the dosing disc is a single piece construction and rotates about the respective vertical axis in the same vertical plane. Pellets get filled in the vertical passages in the dosing disc under gravity. Therefore, there are chances that the vertical passages may not get filled to the required level. This may lead to weight and dosage variations which will have serious consequences, especially in the case of pharmaceuticals, neutraceuticals and food supplements, particularly when the dosages are in very small quantities.

While the bottom support plate oscillates in the horizontal plane circumferentially underneath the dosing disc in sliding contact with the dosing disc, there are chances for the pellets to get crushed between the dosing disc and the bottom support plate as the distance or extent of travel of the bottom support underneath the dosing disc is long and the surface area of contact between the two is large. This will not only cause weight and dosage variations but will also result in wastage and loss of material and dust generation. Dust will also clog the interphase between the dosing chambers and the bottom support plate and obstruct smooth sliding movement of the bottom support plate underneath the dosing disc.

Another problem with the above machine is that the size and volume of the vertical passages or metering chambers are fixed and hence the dosage volume is also fixed. Therefore, the machine can handle only one dosage of a fixed volume. In order to fill pellets of different dosages and volumes in capsules, dosing discs having correspondingly sized metering chambers are required to be used. This is inconvenient and cumbersome and also quite expensive.

There is thus need for machines for filling capsules with pellets, which obviate the above problems and maintain accuracy and consistency of dosages and prevent wastage and loss of material and dust generation. There is also need for machines for filling capsules with pellets, which facilitate filling of different dosages of pellets in the capsules.

DETAILED DESCRIPTION OF THE INVENTION
According to the invention there is provided a machine for filling pellets in capsules, including a pellet turret comprising a cylindrical pellet dosing chamber disposed for rotation about a first vertical axis and about a plurality of pellet dosing stations and an ejection station located equidistantly around the first vertical axis cyclically and intermittently at intervals, a top cover for the dosing chamber and a pellet feed means communicating with the dosing chamber, wherein the dosing chamber comprises a plurality of dosing chamber sectors disposed side by side and mounted for rotation about the first vertical axis together and for guided up and down movement relative to one another about the first vertical axis, each of the dosing chamber sectors having atleast one row of main dosage metering passages transversely extending therethrough and a radially displaceable bottom sector plate located underneath the dosing chamber sector and having atleast one row of complementary dosage metering passages extending transversely therethrough matching in position and size with the main dosage metering passages in the dosing chamber sector and wherein the pellet turret comprises a differential drive cum displacement mechanism configured to rotate the dosing chamber cyclically and intermittently at intervals about the first vertical axis and to move up the dosing chamber sectors progressively from the ejection station upto the end dosing station and to move down a dosing chamber sector from the end dosing station to the ejection station about the first vertical axis and to align the complementary dosage metering passages in a bottom sector plate with the main dosage metering passages in the corresponding dosing chamber sector and then to misalign the complementary dosage metering passages in the bottom sector plate with the main dosage metering passages in the corresponding dosing chamber sector at the ejection station in a cycle of operation of the dosing chamber and a piston assembly mounted at the ejection station to push down dosages of pellets in the main dosage metering passages in a dosing chamber sector through the complementary dosage metering passages in the corresponding bottom sector plate aligned with the main dosage metering passages in the dosing chamber sector at the ejection station.

According to the invention there is also provided a machine for filling pellets in capsules, including a pellet turret comprising a cylindrical pellet dosing chamber disposed for rotation about a first vertical axis and about a plurality of pellet dosing stations and an ejection station located equidistantly around the first vertical axis cyclically and intermittently at intervals, a top cover for the dosing chamber and a pellet feed means communicating with the dosing chamber, wherein the dosing chamber comprises a plurality of dosing chamber sectors disposed side by side and mounted for rotation about the first vertical axis together and for guided up and down movement relative to one another about the first vertical axis, each of the dosing chamber sectors having atleast one row of main dosage metering passages transversely extending therethrough, a dosage volume adjustment means and a radially displaceable bottom sector plate located underneath the dosing chamber sector and having atleast one row of complementary dosage metering passages extending transversely therethrough matching in position and size with the main dosage metering passages in the dosing chamber sector and wherein the pellet turret comprises a differential drive cum displacement mechanism configured to rotate the dosing chamber cyclically and intermittently at intervals about the first vertical axis and to move up the dosing chamber sectors progressively from the ejection station upto the end dosing station and to move down a dosing chamber sector from the end dosing station to the ejection station about the first vertical axis and to align the complementary dosage metering passages in a bottom sector plate with the main dosage metering passages in the corresponding dosing chamber sector and then to misalign the complementary dosage metering passages in the bottom sector plate with the main dosage metering passages in the corresponding dosing chamber sector at the ejection station in a cycle of operation of the dosing chamber and a piston assembly mounted at the ejection station to push down dosages of pellets in the main dosage metering passages in a dosing chamber sector through the complementary dosage metering passages in the corresponding bottom sector plate aligned with the main dosage metering passages in the dosing chamber sector at the ejection station.
DESCRIPTION OF FIGURES OF THE DRAWINGS
Fig 1 of the accompanying drawings is a schematic plan view of the pellet turret of a machine for filling pellets in capsules according to an embodiment of the invention without the top cover, pellet feed tube, piston assembly and differential drive cum displacement mechanism according to an embodiment of the invention;

Fig 2 of the accompanying drawings is another schematic plan view of the pellet turret of Fig 1 including a part of the differential drive cum displacement mechanism;

Fig 3 is a schematic sectional view of the pullet turret of Fig 1 across the dosing station C and ejection station F of the pullet turret including the top cover, pellet feed tube and part of the differential drive cum displacement mechanism;

Fig 4 is an enlarged schematic part sectional view of the pellet turret of Fig 3 at the ejection station;

Fig 5 is another enlarged schematic scrap view of the pellet turret of Fig 3 at the ejection station;

Fig 6 is an enlarged schematic scrap sectional view of the pellet turret of Fig 1 at a dosing station;

Fig 7 is another schematic sectional view of the pellet turret of Fig 3;

Fig 8 is a schematic scrap sectional view of a dosing chamber sector of the pellet turret of Fig 1 mounted to a support block;

Fig 9 is a schematic part sectional view of the pellet turret of Fig 1 including the flexible material scraper blade;

Figs 10a and 10b are schematic isometric views of the main cam body of the pellet turret of Fig 1 from opposite sides thereof;

Fig 11 is a schematic exploded view of a dosing chamber sector of the pellet turret of Fig 1;

Fig 12 is a schematic sectional view of a bush of the dosing chamber sector in Fig 11;

Fig 13 is a schematic exploded view of part of the differential drive cum displacement mechanism of the pellet turret of Fig 1; and

Fig 14 is a schematic sectional view of the piston assembly at the ejection station of the pellet turret of Fig 1.

DESCRIPTION OF EMBODIMENT OF THE INVENTION
The pellet turret 1 of a machine for filling pellets in capsules according to an embodiment of the invention as illustrated in Figs 1 to 14 of the accompanying drawings, comprises a cylindrical pellet dosing chamber 2 disposed for rotation about a first vertical axis X1 and about a plurality of pellet dosing stations A, B, C, D and E and an ejection station F located equidistantly around the first vertical axis, cyclically and intermittently at intervals. (Figs 1 – 9).

The dosing chamber 2 is closed at the top with a top cover 6 comprising a flat rim 7 having a centre opening 8 with a stepped sidewall 9 and a circular cover member 10 projecting down from the bottom surface of the flat rim over the top portion of the pellet dosing chamber. A lid 11 having a complementary stepped outer surface 12 is removably located against the stepped sidewall of the centre opening in the flat rim. A pellet feed tube 13 extends into the pellet dosing chamber through the flat rim (Figs 3, 4, 7, 9).

22 is a differential drive cum displacement mechanism including a stepped diameter spindle 3 disposed for rotation about the first vertical axis cyclically and intermittently at intervals and having a large or wide diameter portion 4 and a narrow or small diameter portion 5. The dosing chamber 2 comprises a plurality of dosing chamber sectors or segments 14 disposed side by side. Each of the dosing chamber sectors comprises a base portion 15 having inner side 16 in sliding contact with the sidewall of the large diameter portion 4, an outer side having an upstanding sidewall 17 and a flat bottom surface 18. The base portion has a row of main dosage metering passages (main dosage metering chambers) 19 extending transversely therethrough (Figs 1 – 7, 11).

Each of the dosing chamber sectors 14 has a radially displaceable bottom sector plate or segment plate 20 located underneath the base portion 15 against the flat bottom surface 18 of the base portion. Each of the bottom sector plates 20 is T-shaped having a cross limb 53 and a perpendicular limb 54. The cross limb is radially displaceably disposed underneath the base portion 15 of each of the dosing chamber sectors 14 against the flat bottom surface 18 thereof and has atleast one row of complementary dosage metering passages (complimentary dosage metering chambers) 21 extending transversely therethrough matching in position and size with the main dosage metering passages 19 in the base portions of the dosing chamber sectors. (Figs 1 – 7, 9, 11, 13).

A stationary upright cylindrical main cam body 22a is disposed over the narrow diameter portion 5 of the stepped diameter spindle 3. The main cam body comprises a main cam groove 23 around it. A plurality of support blocks 24 are disposed around the main cam body corresponding to the number of dosing chamber sectors. Each of the support blocks is disposed underneath each of the dosing chamber sectors and has a main cam follower 25 fixed at the centre of the inner side 26 of the support block in hole 26a and slidably engaged in the main cam groove (Figs 3, 4, 9, 10a, 10b, 13).

Each of the support blocks 24 is mounted to the bottom of the large diameter portion 4 of the stepped diameter spindle 3 with a pair of vertically spaced guide rods 27, 27 having their top ends fixed to the bottom of the large diameter portion 4 and their bottom ends engaged to the inner side 26 of each of the support blocks through bush bearings 29, 29 housed in holes 29a, 29a at the inner side of each of the support blocks. Each pair of guide rods are equally spaced from the centre of the support block. The support blocks are held to the guide rods but are movable up and down on the guide rods against the bush bearings 29, 29 in the support blocks (Figs 1, 2, 7, 13). The up and down movement of the support blocks is guided on the guide rods.

Each of the support blocks 24 has a pair of spaced upright bosses 30, 30 at the outer side 31 thereof, each equidistantly spaced from the centre of the support block. Each of the dosing chamber sectors 14 is fixed to a pair of upright bosses on each of the support blocks against the base portions 15 of the dosing chamber sectors with bolts 32 tightened in bolt holes 33 in the base portions and bolt holes 34 in the bosses (Figs 1, 2, 8, 11, 13).

When the stepped diameter spindle 3 rotates about the first vertical axis X1, the dosing chamber sectors 14 of the dosing chamber 2 in sliding contact with the large diameter portion 4 of the spindle rotate together about the spindle 3 and about the dosing stations A – E and ejection station F. The support blocks 24 mounted to the dosing chamber sectors and the main cam followers 25 fixed to the support blocks also rotate with the dosing chamber sectors. While the dosing chamber sectors rotate about the spindle, the main cam followers 25 slide and rotate in the main cam groove 23 on the main cam body 22a which remains stationary.

The trajectory and geometry of the main cam groove is configured and profiled to allow the main cam followers to move up and down in the main cam groove 23 with the associated support blocks 24 and thereby move up and down or float the dosing chamber sectors 14 mounted to the support blocks relative to one another about the various stations with respect to the large diameter portion 4 of the stepped diameter spindle 3 as explained in detail in the following description relating to the operation of the machine. During the up and down movement of the support blocks 24 with the dosing chamber sectors 14, they are guided on the guide rods 27, 27 to maintain the dosing chamber sectors in position.

It should be understood that the tolerances or gaps between the inner sides 16 of the base portions 15 of the dosing chamber sectors 14 and the large diameter portion 4 of the spindle 3 and the tolerances or gaps between the sides of the dosing chamber sectors are precisely controlled in such a manner that leakage of pellets from the dosing chamber 2 does not takes place and that the pellets do not get crushed and damaged and that the pellets do not clog and obstruct smooth rotation of the dosing chamber and that the dosing chamber sectors move up and down or float relative to one another smoothly.

A rail 35 is horizontally disposed in locating groove 35a at the centre of the top surface 35b of each support block 24 between the respective upright bosses 30,30 and fixed thereto. A channel slide 36 is horizontally slidably engaged over the rail. A vertically displaceable member or finger 37 is disposed over the outer side 31 of each support block between the upright bosses of the support block through a slot 37a in the vertically displaceable member. The vertically displaceable member has an inwardly projecting top sidewall 39 disposed over the channel slide and mounted thereto and an inwardly projecting bottom sidewall 40 engaged over the bottom surface 41 of the support block. The bottom sidewall 40 has a V-shaped notch 42 (Figs 3, 4, 9, 13).

A fulcrum pin 43 is disposed for oscillation about a second vertical axis X2 in a bush 44 at the ejection station of the pellet turret. The bush is supported in the pellet turret frame 45. Axis X2 is in the proximity of and parallel to axis X1. An upper oscillator arm 46 is horizontally disposed and has one end fixed to the top end of the fulcrum pin and the other end fixed to a vertically displaceable actuator 47 at the ejection station. The actuator is disposed in the rotary path of the support blocks 24 carrying the vertically displaceable members 37 at the outer sides 31 thereof and the dosing chamber sectors 14. The actuator 47 is profiled to releasably engage in the V-shaped notch 42 of the bottom sidewall 40 of the vertically displaceable member 37. A lower oscillator arm 48 is disposed horizontally and parallel to the upper oscillator arm and has one end fixed to the bottom end of the fulcrum pin and the other end fixed to an auxiliary cam follower 49 engaged in an auxiliary cam groove 50 in an auxiliary cam body 51 mounted to a shaft 52 disposed for rotation about a third vertical axis X3. The third vertical axis is in the proximity of and parallel to the second axis X2. (Figs 2, 3, 4)

The trajectory and geometry of the auxiliary cam groove 50 is configured and profiled to cause the auxiliary cam follower 49 to describe an oscillatory motion (reciprocating motion) in the horizontal plane and to cause the fulcrum pin and the oscillatory arms to describe an oscillatory motion in an horizontal plane and displace the vertically disposed actuator 47 in opposite directions radially with respect to the dosing chamber sectors.

The cross limb 54 of each of the bottom sector plates 20 is disposed between each pair of upright bosses 30, 30 at the outer side 31 of the support blocks 24 over the top sidewall 39 of each vertically displaceable members 37 and mounted to the top sidewall of the vertically displaceable members. Therefore, on displacing the vertically displaceable members 37 in opposite directions radially with respect to the dosing chamber sectors 14, the channel slides 36 slide on the rails 35 at the top surface of the support blocks 24 in opposite directions radially with respect to the dosing chamber sectors. The slots 37a in the vertically displaceable members 37 allow the vertically displaceable members to move in opposite directions radially with respect to the dosing chamber sectors with the channel slides 36 guided and movable on the rails 35 fixed at the top surface 35b of the support blocks. The vertically displaceable members are also guided at the bottom with the bottom sidewall 40 thereof engaged over the bottom surface 41 of the support blocks 24. (Figs 1, 2, 3, 4, 5, 6, 7, 9, 13).

Since the perpendicular limbs 54 of the bottom sector plates 20 are mounted to the top sidewall of the vertically displaceable members on displacing the vertically displaceable members in opposite directions radially with respect to the dosing chamber sectors, the bottom sector plates 20 also move with the vertically displaceable members. As a result, the cross limbs 53 of the bottom sector plates abutting against the flat bottom surfaces18 of the base portions 15 of the dosing chamber sectors 14 move in opposite directions radially with respect to the dosing chamber sectors to align and misalign the complementary dosage metering passages 21 in the cross limbs of the bottom sector plates 20 with main dosage metering passages 19 in the base portions 15 of the dosing chamber sectors 14.

The pellet turret also comprises a piston assembly 55 mounted at the ejection station F of the pellet turret. The piston assembly comprises a row of pistons 56 corresponding to a row of main dosage metering passages 19 in a dosing chamber sector 14 and a row of complementary dosage metering passages 21 in a bottom sector plate 20 and matching in position with the row of main dosage metering passages and the row of complementary dosage metering passages. The piston are mounted in a horizontally disposed piston mounting plate 57 which is mounted to another plate 58. Plate 58 is mounted to upright guide rods 59 which are up and down movably housed in housings 60 and guided in the housings. The housings 60 are in turn mounted to the pellet turret frame 45.

The pistons are mounted for up and down with the piston mounting plate axially into and out of the pellet dosing chamber 2 through openings (not shown) in the top cover 6. The pistons have narrow tips 61 sized and shaped to enter the main dosage metering passages in the dosing chamber sectors and corresponding complementary dosage metering passages in the bottom sector plates. (Figs 4, 7, 10, 14, 17). Bush bearings 62 are provided in the housings 60 for smooth up and down movements of the guide rods 59 in the housings with the piston mounting plate and pistons. (Figs 3, 4, 5, 7, 14).

An ultrasonic vibrator 63 is mounted to the piston mounting plate 57 for vibrating the piston mounting plates 57 and 58 and pistons 56 in the vertical plane in a narrow amplitude range of 20 to 60 microns while the piston mounting plates with the pistons move up and down axially. The housings 60 provide sufficient clearance for the guide rods with the piston mounting plates and pistons to oscillate in the narrow amplitude range.

Drive for rotating the stepped diameter spindle 3 about the vertical axis X1 cyclically and intermittently at intervals, drive for rotating the shaft 52 about the vertical axis X3 and drive for moving the piston mounting plates 57 and 58 and pistons 56 up and down axially have not been illustrated and described as such are not necessary for understanding the invention.

A flexible material scraper blade 64 extends down into the pellet dosing chamber 2 from the top cover 6 upto the mouth of the main dosage metering passages 19 in the dosing chamber sectors 14 (Fig 9). The scraper blade is positioned between the ejection station F and the end pellet dosing station E immediately preceding the ejection station.

Each of the dosing chamber sectors 14 optionally comprises a recess 65 in the base portion 15 thereof. The main dosage metering passages 19 extend transversely through the recess. A vertically adjustable section plate 66 sized to sit in the recess is located in the recess. The vertically adjustable section plate has a row of supplementary dosage metering passages (supplementary dosage metering chambers) 67 transversely extending therethrough registering in size and position with the main dosage metering passages in the base portion of the dosing chamber sector. Each section plate has a bolt hole 68 at the inner side centre thereof.

Each section plate is vertically adjustably held in the recess with a bolt 69 extending down through the bolt hole in thread engagement with the bolt hole and is rotatably held in position to the base portion of the dosing chamber sector with a circlip 70. Each section plate is locked in position with a check nut 71 tightened on the bolt against the top surface of the section plate. On rotating the bolt 69 in opposite directions in the unlocked portion thereof, the bolt rotates in the same horizontal plane and the section plate moves up and down in the recess. (Figs 3, 4, 5, 6, 7, 9, 11).

A row of open ended removable dosing bushes 72 extend through the supplementary dosage metering chambers 67 in the section plates 66 and corresponding main dosage metering passages 19 in the bottom portion 15 of the dosing chamber sectors 14. By adjusting the height of the section plates with respect to the base portions of the dosing chamber sectors by operating the bolts 69, the effective space between the supplementary dosage metering passages in the section plates and corresponding main dosage metering passages in the base portions of the dosing chamber sectors can be adjusted so as to accommodate bushes of different volumes in the supplementary dosage metering passages and corresponding main dosage metering passages and thereby enable the dosing chamber sectors of the dosing chamber 2 to handle dosages of different volumes of pellets in the same pellet turret. The piston tips 61 are sized and shaped to enter the bushes 72 and push down the dosages of pellets in the bushes. The bushes have collars 72a and 72b to locate the bushes against the top surface of the section plates and the top surface of the base portions of the dosing chamber sectors, respectively. (Figs 3, 4, 5, 6, 7, 9, 11).

The pellet turret 1 operates in synchronization with a capsule turret (not shown) of the machine in a cyclic manner intermittently at intervals. Both the pellet turret and capsule turret are disposed side by side. In one configuration, the capsule turret comprises a capsule carrier disc disposed for rotation about a vertical axis cyclically and intermittently at intervals. The capsule carrier disc is rotatable about a plurality of capsule handling stations located equidistantly around the periphery of the capsule carrier disc including a capsule filling station. The capsule carrier disc comprises a plurality of rows of capsule holding grooves extending transversely through the periphery of the capsule carrier disc in the same layout as the main dosage metering passages 19 in the bottom portions 15 of the dosing chamber sectors 14. The capsule turret has not been illustrated and described in further detail as such is known to a person skilled in the art and is not necessary for understanding the invention.

During cyclic operation of the pellet turret 1, pellets 73 are fed into the dosing chamber 2 consisting of the dosing chamber sectors 14 through the pellet feed tube 13 to form a pellet bed in the dosing chamber. The dosing chamber rotates about the large diameter portion 4 of the stepped diameter spindle 3 and about the dosing stations A to E and ejection station F of the pellet turret intermittently at intervals. While the dosing chamber sectors 14 rotate or index to the dosing station A and rotate or index about the dosing stations A to E, they also move up or slide up against the large diameter portion 4 of the stepped diameter spindle 3 at the dosing stations A to E progressively relative to one another.

As the dosing chamber sectors move up progressively relative to one another, the main dosage metering passages 19 in the dosing chamber sectors 14 are lifted up and forced through the pellet bed progressively. As a result, the main dosage metering passages get filled up in full with the pellets. While the main dosage metering passages are getting filled up with the pellets, the bottom sector plates 20 remain underneath the flat bottom surfaces 18 of the base portions 15 of the dosing chamber sectors with the complementary dosage metering passages 21 in the bottom sector plates misaligned with the main dosage metering passages in the dosing chamber sectors radially. Therefore, the dosages of pellets 73 being formed in the main dosage metering passages remain in the main dosage metering passages against the bottom sector plates.

When the dosing chamber sector 14 at the end dosing station E immediately preceding the ejection station F indexes to the ejection station, it moves or floates down against the large diameter portion 4 of the stepped diameter spindle 3. While indexing down, the flexible material scraper blade 64 positioned between the ejection station F and the pellet dosing station E scrapes and removes excess pellets at the mouth of the main dosage metering passages 19 in the dosing chamber sector 14.

The rotational movements of the pellet turret 1 and capsule turret of the machine and the up and down movements of the piston assembly 55 and the dosing chamber sectors 14 are so synchronised that in each cycle of operation of the machine when a dosing chamber sector 14 formed with dosages of pellets 73 indexes to the ejection station F of the pellet turret, a row of capsules bodies 74 in a row of capsule holding grooves of the capsule carrier disc indexes to the capsule filling station of the capsule turret and positions below the dosing chamber sector at the ejection station with their mouths directed upwards.

When the dosing chamber sector 14 with the dosages of pellets and corresponding bottom sector plate 20 is at the ejection station, the vertically displaceable actuator 47 at the other end of the upper oscillator arm 46 engages in the V-shaped notch 42 at the bottom sidewall 40 of the vertically displaceable member 37 corresponding to the dosing chamber sector.

The auxiliary cam body 51 with the shaft 52 rotates about the axis X3 in a direction radially inwardly with respect to the dosing chamber sector (forward stroke). As a result, the auxiliary cam follower 49 describes a forward stroke in the auxiliary cam groove 50. The fulcrum pin 43 with the upper oscillator arm 46 and lower oscillator arm 48 oscillate about axis X2 in one direction radially inwardly with respect to the dosing chamber sector. The vertically displaceable member 37 moves outwardly on the rail 35 at the top surface 35b of the support block 24 and the bottom sector plate 20 mounted to the vertically displaceable member moves radially inwardly underneath the dosing chamber thereby aligning the complementary dosage metering passages 21 in the bottom sector plate with the main dosage metering chambers 19 in the bottom portion 15 of the dosing chamber sector 14 (Figs 3, 4, 5). The channel slide 36 moves out on the rail 35 in one direction radially inwardly with respect to the dosing chamber sector to allow the vertically displaceable member 37 and the bottom sector plate 20 to move radially inwardly.

The piston mounting plates 57 and 58 with the pistons 56 move down and push the dosages of pellets in the main dosage metering passages 19 in the dosing chamber sector into the capsule bodies 74 disposed below the bottom sector plate through the complementary dosage metering chambers 21 in the bottom sector plate 20. On ejection of the dosages of pellets, the piston mounting plates and pistons move upto their original position. While the piston mounting plates 57 and 58 with the pistons 56 move up and down axially, the ultrasonic vibrator 63 vibrates the piston mounting plates and the pistons in the narrow amplitude range of 20 to 60 microns in the vertical plane. Therefore, when the pistons push down the dosages of pellets in the main dosage metering passages 19 in the dosing chamber sectors 14 through the complementary dosage metering passages 21 in the bottom sector plates 20 or through the dosing bushes 72 and the complementary dosage metering passages in the bottom sector plate, the dosages of pellets are also subjected to vibration and pellets that happen to be stuck in the main dosage metering passages or in the dosing bushes and complementary dosage metering passages are dislodged and push down into the capsule bodies.

After the dosages of pellets in the dosing chamber sector are ejected at the ejection station, the auxiliary cam body 51 with the shaft 52 rotates about the axis X3 in the reverse direction radially outwardly with respect to the dosing chamber sector (reverse stroke). As a result, the auxiliary cam follower 49 describes a reverse stroke in the auxiliary cam groove 50. The fulcrum pin 43 with the upper oscillator arm 46 and lower oscillator 48 oscillate about axis X2 back to the original position ie in the opposite direction radially outwardly with respect to the dosing chamber sector. The vertically displaceable member 37 moves inwardly on the rail 35 at the top surface 35b of the support block 24 and the bottom sector plate 20 mounted to the vertically displaceable member moves radially outwardly underneath the dosing chamber sector thereby misaligning the complementary dosage metering passages in the bottom sector plate with the main dosage metering passages in the dosing chamber sector (Figs 6, 9). The channel slide 36 moves in on the rail 35 in the opposite direction radially outwardly with respect to the dosing chamber sector to allow the vertically displaceable member 37 and the bottom sector plate 20 to move radially outwardly.

The cycle of operation of the pellet turret is complete and the dosing chamber sector 14 at the ejection station F with the main dosage metering passages 19 closed at the bottom with the bottom sector plate 20 is ready to index and move up progressively to the dosing station A and start the next cycle of operation. The capsule turret with the capsule carrier disc having the capsule bodies filled with the dosages of pellets indexes to the subsequent station of the capsule turret.

The differential drive cum displacement mechanism, dosing chamber sectors and the piston assembly all can be of different designs (constructions or configurations). The dosing chamber sectors can be mounted for rotation about the first vertical axis in unison and for guided up and down movements in a different manner. Instead of ultrasonic vibrator, other vibrators such as mechanical, pneumatic or electric vibrators can be used for the piston assembly. The flexible material scraper blade can be of a different construction. A nitrogen jet can be used to remove excess pellets at the mouth of the main dosage metering passages in the dosing chamber sectors instead of or in combination with the scraper blade.

The volume adjustment means of the dosing chamber sectors comprising the vertically adjustable section plate and removable dosing bushes can be of a different configuration or construction. Instead of providing the height adjustable bolts at the inner side centre of the section plates, they can be provided at the outer side centre of the section plates. The number of dosing stations of the pellet turret can be different. Instead of pellets, the pellet turret also can be used to handle other solid materials like granules or microtablets as the invention eliminates tamping plungers or pistons. Such variations of the invention should be construed and understood to be within the scope of the invention.

According to the invention tamping pistons or plungers have been eliminated. The dosing chamber is segmented construction comprising discrete dosing chamber sectors mounted for rotation in unison about a first vertical axis and for guided up and down movement relative to one another during intermittent rotation of the dosing chamber about the first vertical axis. As the dosing chamber sectors move up progressively sequentially, the main dosage metering chambers of the dosing chamber sectors get filled up with the pellets fully and uniformly. Excess pellets at the mouth of the main dosage metering passages are removed by the flexible material scraper blade before the dosing chamber sectors index to the ejection station. The pistons at the ejection station push out the dosages of pellets in the main dosage metering passages very effectively as the pistons are also subjected to vibrations in the vertical plane while moving up and down axially. Because of all this, weight and dosage variations are prevented and uniformity of dosages is maintained. This is particularly useful where the dosages are in extremely small quantities and are very expensive drug or medicine where even small and minute dosage variations are very critical.

According to the invention it is also possible to adjust the size and volume of the dosages of pellets using dosing bushes of different sizes and volumes in the supplementary dosage metering passages in the vertically adjustable section plates and corresponding main dosage metering passages in the dosing chamber sectors and to handle different dosages of pellets in the same pellet turret in a simple manner. The space between the base portions of the dosing chamber sectors and section plates can be easily adjusted to accommodate dosing bushes of different sizes by operating the bolts 69 easily. Discrete construction of the dosing chamber reduces effort for volume adjustment and makes it easy. However, the dosage volume adjustment means according to the invention is optional.

As the bottom sector plates slide radially inwardly and outwardly underneath the base portions of the dosing chamber sectors to align and misalign the complementary dosage metering passages in the bottom sector plates with the main dosage metering passages in the base portions of the dosing chamber sectors, the extent sliding of the bottom sector plates against the base portions of the dosing chamber sectors and the surface area of contact between the bottom sector plates and base portions of the dosing chamber sectors during sliding is limited. Therefore, chances for the pellets to get crushed between the bottom sector plates and the base portions of the dosing chamber sectors are practically eliminated. As a result of this also, weight and dosage variations of dosages are practically eliminated. Dust generation and wastage of valuable material are also practically eliminated.

As the sliding movement of the bottom sector plates against the dosing chamber sectors is reduced substantially, force required for movement is reduced, frictional forces are reduced and wear and tear to the components is also reduced. Movement of the bottom sector plates against the dosing chamber sectors is easy and smooth.