The present invention relates generally to methods and systems for loading tablets, including micro-tablets, into containers.
Tablets are prevalent in various fields including in the pharmaceutical, veterinary and confectionary fields. Tablets can be manufactured in a wide range of sizes. For example, typical disc shaped tablets may have diameters in the range of 5 mm to 20 mm and thicknesses in the range of 3 mm to 10 mm. One particular category of tablets is that of “micro-tablets”, which are named as such due to their relatively small dimensions. For example, disc shaped micro-tablets may have diameters in the range of 2 mm to 3 mm and thicknesses in the range of 0.6 mm to 0.9 mm.
Tablets can be made in a wide variety of cross-section shapes such as circular shapes, diamond shapes, arrow-head shapes and hexagonal shapes. Regardless of the cross sectional shape, many tablets are formed in a generally flattened shape with two opposed sides having typically with significantly larger surface areas than the other sides. Typically, those two larger surfaces have opposed sides are oriented generally parallel to each other. A common example is a generally disc shaped tablet. Despite having sides that may be slightly convex, concave or bevelled with for example bisectional lines, many tablets lend themselves to being packaged into a specifically designed and configured container, and being held in a “stacked” formation within the container with the largest side surfaces of the tablets being adjacent to each other (i.e. the tablets are generally lying flat, one on top of another with their largest surface areas generally facing the largest surface area of an adjacent tablet).
Some containers are referred to as cartridges if the container holding a plurality of tablets is intended to be used in conjunction with a dispensing device, such that loaded tablets can be dispensed from the cartridge by the dispensing device. In many such devices, the stacked orientation can help in preventing jamming.
A plurality of tablets may be loaded into a container that has a generally complimentary cross-sectional area sized and shaped to appropriately receive and hold tablets in a stacked configuration. In the aforementioned example, disc shaped tablets may lend themselves well to being packaged in a stacked formation in a container having at least one longitudinally extending channel or tube that is generally cylindrically shaped. Among other things, such a stacked orientation of a plurality of tablets typically minimizes the space occupied by tablets and allows a maximum number of tablets to be loaded into a given container. Stacking of tablets may also assist in ensuring that a specific and predetermined number of tablets are consistently loaded into and held in each container in a series of containers.
In some known types of systems for packaging tablets, loading of the tablets into the actual container takes place by allowing the tablets to free fall under the influence of gravity into and within a container. The container is generally oriented such that the channel is oriented generally vertically and is held stationary during loading. However, such a loading of tablets within the channel is unpredictable due to the inherently random nature of free fall as tablets fall into these containers. It is far from certain that the tablet will come to rest in a flattened stationary orientation within the channel, such that tablets will be stacked in a flat configuration against adjacent tablets in the container. This unpredictability is even more pronounced with smaller lighter tablets, such as micro-tablets which may be subject to a significant degree of turbulence in free fall and may encounter more electrostatic interaction with the container. Thus, it is quite possible that at the end of the free fall into the container, the tablet will not come to rest in the flat orientation required for stacking.
Accordingly, an improved method and system is desirable which can enhance the chances of properly seating tablets in a stacked orientation during the loading of the container.
According to an aspect of the present invention there is provided a system for stacking a plurality of tablets within a container comprising: (a) a container comprising a generally elongated channel having a first end and a second end, the first end being positioned above the second end and having an aperture for receiving a plurality of tablets in series into the channel, the second end providing at least partial support for a plurality of tablets stacked within the channel; (b) a container holding apparatus for releasably holding the container; (c) a vibration device operable to apply linear vibration to the container while the container is being held by the holding apparatus; and (d) a tablet delivery system operable to deliver the plurality of tablets sequentially to the first end of the channel; wherein the linear vibration of the container provided by the vibration device aligns the sequentially loaded plurality of tablets received into the channel in a stacked formation within the channel.
According to another aspect of the present invention there is provided a system for packaging a plurality of tablets comprising: (a) a container comprising a generally elongated channel having a first end and a second end positioned below the first end, the first end having an aperture for receiving a plurality of tablets in series into the channel; (b) a container holding and vibration apparatus operable to hold the container and concurrently apply linear vibration in a direction to the container; and (c) a tablet delivery system operable to deliver the plurality of tablets in series to the first end of the container in a direction that is substantially in alignment with the direction of linear vibration of the container, wherein the linear vibration of the container provided by the vibration device is operable to align the sequentially loaded plurality of tablets in a stacked formation within the channel of the container.
According to yet another aspect of the present invention there is provided a system for packaging a plurality of tablets comprising: (a) a container comprising a generally elongated channel having a first end and a second end, the first end having an aperture for receiving a plurality of tablets in series into the channel; (b) a container holding and vibration apparatus operable to hold the container and concurrently apply linear vibration in a direction to the container; and (c) a tablet delivery system operable to deliver the plurality of tablets in series in an on-edge orientation to the first end of the container in a direction that is substantially in alignment with the direction of linear vibration of the container, (d) a tablet detection and counting system for detecting each of the plurality of tablets being delivered by the tablet delivery system while each of the plurality of tablets in the on-edge orientation; wherein the linear vibration of the container provided by the vibration device is operable to align the sequentially loaded plurality of tablets in a stacked formation within the channel of the container.
According to a further aspect of the present invention there is provided a method of loading a container having an elongated channel with tablets, the method comprising: (a) loading the channel with a plurality of tablets; (b) applying linear vibration to the channel containing the tablets; wherein the linear vibration of the channel is operable to align the plurality of tablets in a stacked formation within the channel.
According to a still further aspect of the present invention there is provided a system of loading a container having an elongated channel with tablets, the method comprising: (a) a means for loading the channel with a plurality of tablets; (b) a means for applying linear vibration to the channel containing the tablets; wherein the linear vibration of the channel is operable to align the plurality of tablets in a stacked formation within the channel.
Other aspects and features of the present invention will become apparent to those of ordinary skill in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures.
In the figures which illustrate by way of example only, embodiments of the present invention,
a is a perspective view of components of the system of
With reference to
With particular reference to
Container 146 may be formed in a generally flattened cuboid shape and may have at least one tube or channel 148 formed in a generally cylindrical shape extending longitudinally for at least a portion of the length of the container between an opening 150 towards a base 151. Container 146 and channel 148 may have a wide range of dimensions, depending upon the number, shape and size of tablets to be held in the container, and may have a generally circular cross-section that is large enough to accommodate the tablets in a stacked orientation in the channel.
With reference to
Tablet filling system 10 may also include a programmable logic controller (“PLC”) 18 (only shown schematically in
System 10 may also include a vibration controller device 19 (shown only schematically in
Support frame 199 may provide support for at least some of the components of system 10. Support frame 199 may include a horizontal, transversely and longitudinally extending upper support plate 38 and lower base plate 29 that are interconnected to each other by support legs 31a-c. Support plate 38 may thus be supported by legs 31, with legs 31a-c being mounted to a lower horizontal surface 38b of support plate 38 of frame 199 by, for example, bolts/screws (not shown). Legs 31a-c may also be interconnected to base plate 29 of frame 199, with the bottom surfaces of legs 31 being mounted to upper surface 29a of base 29 by, for example, bolts/screws (not shown). Support frame 199 may also include a vertically and longitudinally extending vibration support plate 116. Support plate 116 may be interconnected and joined to lower horizontal surface 38b of lower support plate 38 by way of, for example, welding, bolts/screws or another known connection mechanism. Support plate 116 may provide support for cartridge holding and vibration apparatus 16.
Sorting bowl apparatus 12 may be mounted on top of upper support plate 38 of frame 199 and may consist of several components including a bowl 20, a bowl support frame 22, and a vibration unit (not shown) that may be housed inside an oriented cylindrical housing unit 34 that forms part of bowl support frame 22. Numerous different types of known sorting bowl units may be used in system 10. Sorting bowl 20 may, for example, be a cylindrical, stepped or conical sorting bowl.
With particular reference to
With reference to
Movement of the tablets 32 may be caused solely by the vibration transferred from the vibrator unit mounted below the bowl inside housing 34. The channel 30 may be machined into the upper surface area of the bowl and may be sized/angled to force the tablets from a flat position to an “on edge” position as they rotate around the bowl into and then clockwise within channel 30. However, in other tablet loading systems, other types of apparatus may be utilized that can deliver tablets sequentially in an on-edge orientation to an aperture in the bowl for delivery in an on-edge orientation to capture wheel 44 of capture wheel apparatus 14.
With particular reference to
With reference to
Lower horizontal surface 34a of housing unit 34 may be interconnected to and supported by several longitudinally extending vertical support legs 36, with support legs 36 being mounted to lower horizontal surface 34a of housing unit 34 by, for, example blots/screws (not shown). Support legs 36 may also be interconnected and supported on the upper surface 38a of horizontally oriented support plate 38 of support frame 199 by for example screws/bolts (not shown).
With particular reference to
Similarly, plate 43b, may have screw hole 41b which may enable screw 141b to pass horizontally through plate 43b horizontally into a threaded hole in the inside surface of recess 45. Plate 43b may have a vertically oriented slot (see
The next component of system 10 to be described in detail is capture wheel apparatus 14. Capture wheel apparatus 14 may have several components including a capture wheel 44 and a capture wheel support frame 48.
Capture wheel support frame 48 will be described in detail with particular reference to
For example, with reference to
Support frame 48 may also include a vertically extending generally cuboid shaped, anchor and spacer block 66 positioned and connected with bolts or screws 68 that pass through openings at inner vertically oriented surface of leg portion 58 of L-shaped support member 54. For example, with reference to
Support frame 48 may also include a horizontal, transversely and longitudinally extending connector plate 79 which may be interconnected and joined to the lower horizontal surfaces of forked plate 72 and shoe 74. Thus, part of the upper surface of connector plate 79 can be held in abutment with the downward facing surface of block 66. With reference to
Capture wheel 44 will now be described in detail with particular reference to
Servo drive motor 80 may have an outer housing 180 that has flanged portions 82. Flange portions 82 may be used to mount motor 80 to outer surface 72a of forked plate 72. For example, with reference to
Capture wheel 44 may be constructed in numerous different ways to provide a plurality of slots/pockets 92 that are positioned at a fixed radial distance and that are angularly spaced about, a central axis of rotation X (
Outer disc 86 may be inscribed with multiple slots/pockets 92 angularly spaced from each other, for example, by a constant angle of 15°. Slots 92 can be configured to be capable of receiving and holding a micro-tablet 32 in an on-edge orientation during rotation of capture wheel 44. The sides of slots 92 may be formed by inner surface portions of outer disc 86a and inner disc 86b. Alternate configurations/constructions are possible for forming capture wheel 44, such that a plurality of open slots like slots 92 may be formed at a constant radius, and spaced around the periphery of a generally circular disc.
This aforementioned construction of capture wheel apparatus 14 provides for relatively easy assembly and disassembly that, for example, slots may be readily cleaned or wheels interchanged so that the system may be easily reconfigured to load different size and/or shaped tablets. Additionally, it should be noted that the width of slot 92 may be readily modified by providing for a shim disc having a configuration like inner disc 86, that may be interposed between outer disc 186 and inner disc 86.
It has been found to be of benefit if the material from which inner disc 186 and outer disc 86 are formed do not have an affinity that attracts the tablets 32 (i.e. the material can be chosen so that tablets 32 tend not to stick in slots 92 and so can be readily discharged from slots 92). Polished aluminium has been found to be one such suitable material for inner disc 186 and outer disc 86.
Shoe 74 may have a complimentary generally inwardly facing arcuate surface 74a (
With reference to
With reference again to
When a tablet 32 passes the electronic beam, it may be broken causing a signal to be sent by micro-sensor 108 to PLC 18. Micro-sensor 108 may obtain an optical signal from the sensing eye which is then converted to a digital signal that may also be amplified. The sensor device 108 will be in electronic communication with PLC 18 such that the digital signal generated by sensor device 108 can be sent to PLC 18. PLC 18 may also be operable to function as a counting device to keep count of the number of tablets passing through feed chute 96 and thus will track how many tablets have been loaded into a given cartridge 146 held in cartridge holding and vibration apparatus 16.
The next component of system 10 to be described in detail is cartridge holding and vibration apparatus 16. Cartridge holding and vibration apparatus 16 may consist of several components including a cartridge holder 112 and cartridge support frame 114. Support frame 114 will now be described in detail with particular reference to
Vertically and longitudinally oriented and extending plate 124 may be mounted at the vertically and longitudinally extending outer surface 118a of plate 118. Plate 124 may be mounted to plate 118 for vertical movement relative to plate 118. For example, with reference to
Extending horizontally and transversely outwards from plate 124 may be a shaft 130. Shaft 130 may have mounted around it a cartridge positioning device 133. Cartridge positioning device 133 may include an O-clamp device 134 that may be releasable secured to and rotated about shaft 130. It will be appreciated that O-clamp may be rotated relative to shaft 130 and may be positioned securely at varying axial positions on shaft 130. As described below, cartridge holding device 112 is secured to O-clamp 134. It will the therefore appreciated that by movement of plate 118 relative to plate 116, and plate 124 relative to plate 118, provides for two degrees of freedom of movement of cartridge holding device 112. The rotational and axial movement of clamp device 134 on shaft 130 extends the type of movement and positioning of cartridge holding device 112 that is possible.
By way of further explanation, by translational movement of plates 118 and 124, and rotational and axial movement of O-clamp device 134, cartridge holding device 112 can be appropriately positioned and angled for loading of container 146 with tablets 32. For example, cartridge holding device may be positioned such that container 146 is oriented longitudinally at an angle of 30° from vertical.
Cartridge holding device 112 will now be described in detail and includes a transversely oriented plate portion 136. The angular position of plate 136 may be adjusted by the positioning of O-clamp 134 on shaft 130, as plate 136 is affixed to a location on the outer surface of O-clamp 134, for example by welding or in a similar known manner.
A vibration device 138 may be supported by and connected to plate portion 136. Vibration device 138 may provide for a vibration of a cartridge 146 held in holding device 112. To be able to achieve the desired stacking of tablets 32 in cartridge 146, the vibration provided by device 138 includes linear vibration of the cartridge (i.e. cyclical forward and backwards movement in the Z direction (see
With reference again to
Jig 142 may be inscribed so as to form a template of generally complimentary shape to micro-tablet cartridge 146. Jig 142 may have portions142a that receive cartridge 146 that are made from a flexible and resilient material such that cartridge 146 can be held by friction fit by jig 142. In this way linear vibrations caused by linear vibrator 138 may be communicated to cartridge 146. Other mechanisms can be used to hold cartridge 146 on jig 142.
Cartridge 146 may have its cylindrical channel 148 aligned parallel to the longest dimension of cartridge 146 and orthogonal to base of cartridge 146. Channel 148 may be capable of receiving micro-tablets 32 and be in vibration communication with linear vibrator 148. The cross-sectional perimeter of container 148 may be of complimentary dimensions and shape to cross sectional area of micro-tablet 32. Upper aperture 150 of container 148 may be positioned at or near lower aperture 101 of feed chute 96. As referenced above, depending upon the configuration of cartridge 146, vertical, longitudinal, transverse and rotational adjustments may be made by way of plates 116, 118 and O-clamp 134 to allow for the angle and position of channel 148 in cartridge 146 to be varied while keeping upper aperture 150 of container 148 near lower aperture 101 of feed chute 96. In this way channel 148 of cartridge 146 may be set at any angle between approximately 0° and 90° degrees while upper aperture 150 of cartridge 148 is kept in close proximity to lower aperture 101.
It will also be appreciated that the use of screws and corresponding holes, along with dowel pins with corresponding apertures, as discussed above, helps ensure that the various parts are properly oriented with respect to each other. This will help ensure that when system 10 is assembled, that everything is precisely oriented to ensure that the micro-tablets move properly and reliably through the system.
Various components of system 10 such as sorting bowl apparatus 12, capture wheel apparatus 14, and cartridge holding and vibration apparatus 16 may be made of suitable materials such as by way of example only sorting bowl apparatus 12 may be made by way of example only from polished aluminium or certain ceramic materials. Also a least some of the various components of system 10 such as sorting bowl apparatus 12, capture wheel apparatus 14 and cartridge holding and vibration apparatus 16 may be integrally formed or interconnected to each other by known techniques. For example if the components are made of a suitable metal or plastic, welding techniques can be employed. Also, the use of screws and/or bolts may be employed.
The operation of system 10 will now be described in detail. First, an empty cartridge 146 that is to be filled with micro-tablets 32 will be placed in jig 142 prior to starting operation of system 10. Also, a relatively large number of micro-tablets 32 may be either by machine or manually pre-loaded into bowl 20 (not shown). Once system 10 is made operational (for example by initiating PLC 18 and controller 19 to be activated) vibration from vibrator located inside housing 34, gravity and the shape of the bottom surfaces 26a and 26b of bowl 20 can cause micro-tablets 32 to vibrate around the bowl 20 ultimately orienting themselves vertically on-edge in single file in channel 30. Micro-tablets 32 may move within channel 30 with tablets being aligned in series within channel 30. Thereafter, one at a time, tablets 32 may move out of bowl 20 via aperture 40 into loading chute 42, while maintaining their vertical on-edge orientation. When a slot 92 is not aligned with the exit aperture from chute 42, a plurality of tablets 32 will remain in series, each in a vertical, on-edge orientation.
To load a single tablet 132 into a slot 92, PLC 18 will rotate capture wheel 44 to a position such that a slot 92 is aligned with the exit aperture 42b from loading chute 42 (
It will be noted as shown in
PLC 18 may drive motor 80 to rotate capture wheel 44 in a clockwise direction and each micro-tablet 32 alternately through positions (a) and (b). In some embodiments, positions (a) and (b) may be the same (i.e. one slot 92 may be being filled from loading chute 42 while another slot 92 may be being discharged as a tablet moves into feed chute 96).
When a micro-tablet 32 is positioned in a pocket 92 that has been aligned with feed chute 96, the rotation of capture wheel 44 can eventually cause that pocket 92 to become aligned the entrance into feed chute 96 that is formed in the lower portion of shoe 74. The tablet may then pass into and through feed chute 96 in vertical on-edge orientation. During such movement through feed chute 96 it can pass micro-sensor 108 before exiting chute 96 to drop into container 148 of cartridge 146. As micro-tablet 32 drops by way of gravity through feed chute 96, micro-sensor 108 may detect passing micro-tablet 32 and register the passing of a tablet 32 with PLC 18, such that a count of tablets passed to a cartridge 146 held in holding and vibration apparatus 16 can be maintained. Detection may be facilitated by the shape of feed chute 96 which presents micro-tablet 32 to micro-sensor 108 in an on-edge orientation thereby presenting the largest surface area of micro-tablet 32 to micro-sensor 108 for detection. After a predetermined and specific number of micro-tablets 32 have been counted, PLC 18 may cause motor 80 to stop rotation of capture wheel 44. In this way, a pre-determined and specific number of micro-tablets 32 can be deposited in channel 148 of cartridge 146. At this point the filled cartridge 146 may be removed and replaced with an empty one, the counter in PLC 18 can be re-set and the capture wheel 44 re-started to begin the process of filling the next cartridge 146.
It should be noted that while tablets 32 are continuing to be sequentially loaded into channel 148 in a vertically on-edge orientation, linear vibration may be applied to channel 148 of cartridge 146 by vibration device 138. Due to the combined effect of: (1) the angle of channel 148 in cartridge 146; and (2) the linear vibration applied to cartridge 146 in a general Z direction, micro-tablets 32 will tend to move and be re-oriented to a position whereby they are oriented in a stacked flat orientation within channel 148. For example, with reference to
In some embodiments filling certain types of tablets, it may not be necessary for channel 148 to be oriented at an angle from the vertical. Stacking of the tablets (into what would according therefore be a stacked horizontal arrangement) may in such embodiments be achieved solely by the linear vibration. In each situation a person skilled in the art will be able select the parameters of the frequency and magnitude of the linear vibration, and the angle at which the channel 148 of the cartridge is held in order to achieve loading of tablets that form a stacked orientation.
After a pre-determined number of micro-tablets 32 have been counted, PLC may send an electronic signal to motor 80 causing motor 80 to stop rotation of capture wheel. In this way, a pre-determined and specific number of micro-tablets 32 can be deposited in channel 148 of cartridge 146. At this point the filled cartridge 146 may be removed and replaced with an empty one. PLC 18 can be re-set and system 10 restarted such that capture wheel 44 recommences the process of filling the next cartridge 146.
By way of example only, a channel 148 in a cartridge that holds 40 micro-tablets may be filled in about 30 seconds using a system 10.
Many variations of the embodiments described above are possible. By way of example only, the system could, with some modifications, function with containers 148 oriented at angles other that 30° and with vibration other than linear vibration.
The systems may also consist of other components that deliver tablets in series to a cartridge holding and vibration apparatus like apparatus 16.
Also, it will be appreciated that the system may be modified to accommodate other types of tablets, capsules, pills or similar products.
Of course, the above described embodiments are intended to be illustrative only and in no way limiting. The described embodiments of carrying out the invention are susceptible to many modifications of form, arrangement of parts, details and order of operation. The invention, rather, is intended to encompass all such modification within its scope, as defined by the claims.
When introducing elements of the present invention or the embodiments thereof, the articles “a,” “an,” “the,” and “said” are intended to mean that there are one or more of the elements. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements.