1. Field of the Invention
The present invention is related generally to a tablet press.
2. Description of Related Art
Presses used for tablet manufacturing are known in the art. Tablet presses wherein an item such as a tablet or core part is placed onto a rotary press die table are also known. For example in some tablet presses, tablet cores are placed within a bed of powder on a rotary press die table and then compressed to create a tablet.
In a first exemplary embodiment, an internal feed wheel assembly is provided with a tablet insert chute and a rotatable bowl top. The tablet insert chute has an exit aperture. The rotatable bowl top has an inner periphery, a plurality of notches, and a plurality of core feed apertures extending therethrough. The exit aperture is positioned proximal to the inner periphery of the bowl top. Each notch is designed and sized to receive a single tablet and is in communication with the inner periphery and a corresponding core feed aperture.
Another exemplary embodiment provides a transfer assembly having a plurality of core retention elements and at least one core feed aperture. The core retention elements are coupled together to form a loop and positioned in a press assembly so as to be rotatable. Each of the core feed aperture is sized to communicate a tablet core therethrough. At least one the core retention elements is positioned in line with at least one core feed aperture.
Yet another exemplary embodiment provides a press assembly having a plurality of core retention elements connected together to form a loop and positioned in a press assembly so as to be rotatable. The plurality of core retention elements are positioned above a plurality of die bores of a press turntable. A plurality of core retention elements each receives a differing amount of an upper punch.
Still another exemplary embodiment provides press assembly having a tablet insert chute with an exit aperture. The press assembly also has a rotatable bowl top with an inner periphery, a plurality of notches, and a plurality of core feed apertures extending therethrough. The exit aperture of the tablet insert chute is positioned proximal to the inner periphery of the bowl top. Each notch is designed and sized to receive a single tablet and is in communication with the inner periphery and a corresponding core feed aperture. A plurality of core retention elements are also provided. The core retention elements are connected together to form a loop positioned in a press assembly so as to be rotatable. Each core feed aperture is sized to communicate a tablet core therethrough. At least one of the core retention elements is positioned in line with at least one of the core feed aperture. At least one of the core retention elements is positioned above at least one die bore of a die turntable.
Another exemplary embodiment provides a press assembly having a tablet insert chute with an exit aperture. The press assembly is further provided with a rotatable bowl top with an inner periphery, a plurality of notches, and a plurality of core feed apertures extending therethrough. The exit aperture of the tablet insert chute is positioned proximal to the inner periphery of the bowl top. Each notch is designed and sized to receive a single tablet and is in communication with the inner periphery and a corresponding core feed aperture. A plurality of core retention elements is also provided. The core retention elements are connected together to form a loop and positioned in a press assembly so as to be rotatable. A plurality of push pins are provided contacting a push pin cam and in line with at least one notch and corresponding core feed aperture and at least one core retention element. At least one core retention element is positioned above at least one powder bore of a die turntable and at least partially receiving an upper punch. at least one core retention element is positioned above a smooth table surface.
Another exemplary embodiment of the present invention provides a method of transporting tablets in a press assembly. The method provides interiorly feeding a tablet into a notch of a rotating top and temporarily maintaining the tablet in the notch.
Another exemplary embodiment of the present invention provides another method of transporting tablets in a press assembly. The method provides a step of causing one of a plurality of rotating attached core retention elements to be placed in proximity to a core feed aperture in line with a tablet. Another step provides communicating a tablet through said core feed aperture into the core retention element when the core retention element is in proximity to the core feed aperture. The method further provides moving the core retention element above a die bore and communicating the tablet from the core retention element and into the die bore.
Still another exemplary embodiment of the present invention provides method of placing tablets in a die bore of a press turntable. The method provides a step of communicating a tablet into a notch of a rotating top in line with a core feed aperture and causing a core retention element to be momentarily placed in proximity to the core feed aperture. The method further provides a step communicating the tablet from the notch, through the core feed aperture, and into the core retention element when the core retention element is in proximity to the core feed aperture. Another step moves the core retention element above the die bore and communicating the tablet from the core retention element and into the die bore.
Yet another embodiment provides an internal feed wheel assembly for a tablet press assembly having a base portion and a tablet insert chute coupled to the base portion and having an exit aperture. The embodiment is also provided with a bowl top rotatably coupled to the base portion, the bowl top has an upper surface, a lower surface and an inner periphery. A plurality of notches are disposed on the lower surface and in communication with the periphery. A first set of a plurality of apertures extend through the upper surface and are in communication with the plurality of notches. The exit aperture of the tablet insert chute is positioned proximal to the inner periphery of the bowl top. Each of the plurality of notches is geometrically dimensioned to receive a single tablet.
Yet another embodiment provides an internal feed wheel assembly for a tablet press assembly having a base portion with a tablet trap and a tablet insert chute coupled to the base portion. A bowl top is rotatably coupled to the base portion, the bowl top has an upper surface, a lower surface and an inner periphery. A plurality of notches are disposed on the lower surface and in communication with the inner periphery. A first set of a plurality of apertures are provided extending through the upper surface and in communication with the plurality of notches. The tablet trap is positioned proximal to the inner periphery of the bowl top. The tablet insert chute exit aperture is located proximal to both the tablet trap and the inner periphery of the bowl top.
In yet another embodiment, a tablet press assembly is provided having a first base portion, and a second base portion. A tablet insert chute is provided coupled to the first base portion and has an exit aperture. A bowl top is rotatably coupled to the first base portion. The bowl top has an upper surface, a lower surface and an inner periphery. A plurality of notches are disposed on the lower surface and in communication with the inner periphery. A first set of a plurality of apertures extend through the upper surface and are in communication with the plurality of notches. A press turntable is rotatably mounted to the second base portion. The press turn table has multiple upper punches, multiple lower punches, and multiple apertures. Multiple core retention elements are provided, each adapted to move between at least a first position proximal to the bowl top and a second position proximal to the press turntable
Embodiments of the present invention are illustrated in the following Figures.
It is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless limited otherwise, the terms “connected,” “coupled,” “in communication with” and “mounted,” and variations thereof herein are used broadly and encompass direct and indirect connections, couplings, and mountings. In addition, the terms “connected” and “coupled” and variations thereof are not restricted to physical or mechanical connections or couplings. Furthermore, and as described in subsequent paragraphs, the specific mechanical configurations illustrated in the drawings are intended to exemplify embodiments of the invention and that other alternative mechanical configurations are possible.
Referring now in detail to the drawings, wherein like numerals indicate like elements throughout the several views, there are shown in
Referring to
With continuing reference to
With reference to
Internal feed wheel assembly 30 receives tablet cores from tablet insert chute 27 or otherwise and transfers those tablet cores to a transfer assembly 50 that may also be located internal to housing 12. In some embodiments, and as will be described in more detail below, internal feed wheel assembly 30 is also driven by transfer assembly 50.
As best illustrated with reference to
As explained in more detail herein, bowl top 32 and bowl bottom 42 rotate when core press assembly 10 is in use and will be rotating when each tablet core 1 is transferred from tablet insert chute 27 or otherwise to back notch 34. Bowl top 32 and internal feed wheel assembly 30 will rotate in a clockwise direction when viewed from above, although this could easily be varied. The close proximity of the inner periphery of bowl top 32 and the exit of tablet insert chute 27, and the gently sloping nature of inward facing groove 33 ensure that a tablet core will not fully exit tablet insert chute aperture 25 until it is in close proximity to the core feed aperture 35 and notch 34 corresponding to the particular inward facing groove 33. As bowl top 32 rotates, only one tablet core 1 will be transferred to each notch 34.
Referring to
Referring now to
In the embodiments shown in
A belt link 54 and chain spacers 55 are utilized to connect a plurality of transfer cogs 56. A plurality of gears 64 having cogs that project between chain spacers 55 are positioned to help move and/or guide transfer assembly 50 when it is moved by upper punches 78 of press turntable 70. The cogs on each of plurality of gears 64 are spaced to fit between chain spacers 55 and to help appropriately guide transfer assembly 50 along its continuous loop. In some embodiments, the plurality of gears 64 may additionally or alternatively drive the plurality of transfer assemblies 50. In some embodiments, shaped surfaces with a low frictional coefficient may be provided in lieu of plurality of gears 64 to help guide transfer assembly 50. Also in some embodiments, the plurality of core retention elements 52 may have a different configuration for transporting tablet cores and may be connected otherwise than with belt 54 to form transfer assembly 50. Vacuum 43 may also be provided in some embodiments near the inner periphery of bowl top 32, at a position where tablet cores are not retained in notch 34, in order to suck and/or blow any debris from bowl top 32.
When transfer assembly 50 is moved by upper punches 78 of press turntable 70 or otherwise, the bowl top 32 is also rotated. In some embodiments, the core retention elements 52 interact with a plurality of equally spaced teeth 40 positioned between core feed apertures 35 to cause bowl top 32 to rotate. Twenty teeth 40 are provided in the embodiment of bowl top 32 shown. During at least a portion of the period when core retention elements 52 interact with bowl top 32 to cause it to rotate, one or more core retention elements 52 will be positioned above one or more corresponding core feed apertures 35.
The push pins 36 are located below bowl top 32 and in line with each notch 34 and each core feed aperture 35. At some point while core retention elements 52 are so positioned, the rotation of bowl top 32 causes push pins 36 to contact push pin cam 38. Push pin cam 38 gradually forces each push pin 36 in an upward direction. Each push pin 36 then contacts one tablet core 1 held in bowl top 32 in line with each push pin 36. Each push pin 36 also forces each tablet core 1 through each core feed aperture 35 and into core retention element 52, where it is temporarily retained by core holder 57. In some embodiments, each inward facing groove 33, tablet trap 37, and each push pin 36 help maintain each tablet core 1 in line with its corresponding core feed aperture 35 from the time each tablet core 1 is released from tablet insert chute 27 until the time each tablet core 1 has been communicated to core retention element 52.
With continuing reference to
With reference to
In some embodiments, at least a portion of the travel of an upper punch 78 and a corresponding core retention element 52 may be synchronized, such that punch 78 and core retention element 52 are substantially aligned along a vertical axis (not shown). The core retention elements 52 are directed into alignment with the upper punch 78 and powder bore 76. As the upper punch 78 moves along (from left to right when viewing
As the core retention element 52, powder bore 76, and upper punch move along, the upper punch 78 contacts the upper punch tamp cam 79. This contact pushes the upper punch 78 down to contact the core push pin 58. As a result, core push pin 58 is driven down and contacts tablet core 1, causing it to be discharged from core holder 57 and onto the corresponding powder bore 76 and powder bed 77. In some embodiments, upper punch 78 is gradually driven down over a number of stages onto core push pin 58 and gradually places any tablet core retained by transfer cog 56 into a bed of powder in its respective die bore 72. For example, upper punch tamp cam 79 may be gradually sloped such that it drives a given upper punch 78 down over a plurality of stages. Thus, at any given time six consecutive upper punches 78 would be contacting and being forced down by upper punch tamp cam 79, with a leading upper punch 78f being driven down the farthest and a trailing upper punch 78a driven down the least. This allows any tablet core 1 to be more slowly and accurately discharged from core holder 57 than if each upper punch 78 is driven down more quickly, such as over only one stage.
A plurality of lower punches 88 are also preferably provided that coincide with and are substantially in line with each upper punch 78. In some preferred embodiments one end of each lower punch 88 forms the base of each powder bore 76. In these embodiments, a lower cam track 80 may be provided. At least a portion of the lower cam track 80 may be gradually sloped to contact and pull down each lower punch 88. The lower punch 88 is pulled down as its corresponding upper punch 78 is driven down onto core push pin 58 and a tablet core 1 is discharged into powder bore 76. Pulling lower punch 88 down increases the volume of the powder bore 72. Thus, allowing room for any powder present in die bore 72 that may be displaced by insertion of a tablet core 1.
This gradual placement of a tablet core 1 over several stages ensures accurate placement of a tablet core 1 in die bore 72 and in the bed of powder present in die bore 72. Moreover, gradual placement of tablet core 1 and the use of lower cam track 80 enables a tablet core to be accurately placed in a variety of positions in the bed of powder and resultantly in the finished tablet. Upper punches 78 may contact upper punch tamp cam 79 over a number of stages besides six, the number of which may depend on a variety of factors, such as, but not limited to, the size of tablet core and the size of the finished tablet.
After an upper punch 78 has been driven down by upper punch tamp cam 79 and caused core push pin 58 to discharge a tablet core, the upper punch 78 is lifted out of the corresponding transfer cog 56, such as by lifting track 74. Core retention element 52 then continues in a loop towards internal feed wheel assembly 30 and bowl top 32 to be refilled with another tablet core 1. The upper punch 78 and its corresponding powder bore 76 and lower punch 88 then preferably continue around press turntable 70 for further processing. In some embodiments, the given powder bore 76 is filled with an additional quantity of powder or the like, preferably by virtue of powder communicated from powder feed 15. Then, each upper punch 78 encounters an upper punch cam 75 that forces upper punch 78 downward into powder bore 76 and compresses tablet core 1 and any present powder between upper punch 78 and lower punch 88 into a singular tablet.
The foregoing description of structures and methods has been presented for purposes of illustration. It is not intended to be exhaustive or to limit the invention to the precise steps and/or forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. It is understood that while certain forms of the core press assembly have been illustrated and described, it is not limited thereto except insofar as such limitations are included in the following claims and allowable functional equivalents thereof.
This application is a continuation of currently pending U.S. patent application Ser. No. 13/168,449, filed Jun. 24, 2011 and entitled “Aspects of a Press Assembly,” which is a continuation of U.S. Pat. No. 8,062,015 (application Ser. No. 12/234,249, filed Sep. 19, 2008, entitled “Tablet Press Assembly”), both of which are hereby incorporated by reference in their entirety.
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Number | Date | Country | |
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20140041539 A1 | Feb 2014 | US |
Number | Date | Country | |
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Parent | 13168449 | Jun 2011 | US |
Child | 14058945 | US | |
Parent | 12234249 | Sep 2008 | US |
Child | 13168449 | US |