US2157570A - Apparatus for making tablets - Google Patents

Description

May 9, 1939. J. A. RAYNOLDS. JR

APPARATUS FOR MAKING TABLETS 2 Sheets-Sheet l Filed Jan. 19. 1937 May 9, 1939 J. A. RAYNOLDS, JR 2,157,570

APARATUS FOR MAKING TABLETS Filed Jan. 19, 1937' 2 sheets-sheet 2 Panarea May 9, 1939 APPARATUS FOR MAKING TABLETS James Albert Raynolds, Jr., Elmhurst, N. Y., assignor to The Atlantic Coast Fisheries Company, New York, N. Y., a corporation of Maine Application January 19, 1937, serial No.`121,2s2

2 Claims.

This invention relates to tablets for pharmafceutical and other purposes. More particularly,

it relates totablets of a predetermined ashape and size and comprising a colloidal matrix having dispersed therein a vitamin-bearing liquid, the vitamin-bearing liquid being completely enveloped in and imprisoned by the matrix so that thereis no vitamin-bearing liquid on the exterior surfaces of the tablet.- Specifically, this invention contemplates apparatus for producing tablets of the type previously mentioned.

Other objects and the nature of the invention will become apparent from the following description, appended claims and accompanying drawings illustrating one embodiment containing the principles of this invention, and wherein:

Figure 1 is a longitudinal section of one illustrative embodiment of an apparatus employing the principles constituting the present invention.

vFigure 2 is a view taken on lines AA o`f Figure 1.

Figure 3 is a detail of a modied form of removing means.

Figures 4, 5, 6 and 7 are plan views of belts showing illustrative molding cavities.

Figures 8, 9, 10 and 11 arelongitudinal sections taken on Figures 4, 5, 6 and '7, respectively.

Though the invention is applicable to the various compositions asv hereinafter explained, it will be described, for illustrative purposes, in specific detail to the manufacture of gelatin tablets containing a vitamin-bearing liquid dispersed therein, the latter being completely enveloped and imprisoned in the gelatin, there being no free vitamin-bearing liquid on the surfaces of the tablet.

In accordance with the principles oftthis invention, an aqueous gelatin solution containing a relatively high concentration of gelatin is prepared at an elevated temperature and, while at .an elevated temperature, the vitamin-bearing oil is emulsied therein. The emulsion, due to the high concentration of gelatin, is characterized in that itis a viscous liquid at an elevated temperature and upon cooling sets to a ilrm jelly. After the emulsion has set to a jelly, it must not be disturbed .until substantially dry, since crushing, pulling, etc. may damage or otherwise destroy the gel structure with the release of droplets of oil contained therein.

'I'he previously described emulsion is supplied at an elevated temperature to a moving belt containing perforations or cavities of a shape and size conforming to'the shape and size of the desired tablets. Immediately after or simultaneously with the introduction of the gelatin emulsion into the perforations or cavities, the emulsion in the molding cavities or perforations is chilled with the result that it is set in the form and shape corresponding and conforming to the perforations or cavities.

The tablets may be removed from the perforations or cavities in various manners. For example, when the molding cavities consist of perforations, the molded objects may be ejected by the use of an appropriate pusher or ejector device.

If the belt is formed of an elastic material, it may be distorted, such as by stretching or passing over an arcuate or curved surface, whereby the perforations or cavities are enlarged. vThe distortion may be small, in whichcase the tablets will be loosened and nally removed by auxiliary means, such as a brush, pusher, etc. Alternately, the distortion may be of suchl magnitude to permit the tablets to fall under the action of gravity from the belt. Manifestly, the various procedures of removing the molded objects may, be used in combination with each other. In order to effect clean removal of the tablets so that there will be no broken or injured surfaces, a lubricating substance is applied to the perforations or cavitie/s prior to the casting of the gelatin emulsion. Obviously, the lubricant must be of such a nature that it does not deleteriously affect the product or in any way intefere with the operation of the method and apparatus. The lubricant also must be of such a nature that it will not deleteriously aiect in any way the belt containing the perforations and molding cavities. The gelatin emulsion is of the type and nature and composition as set forth in copending application Serial No. 105,086. This emulsion is prepared by dissolving gelatin in warm water to produce a solution of fairly high concentrations, such as 30% to 50% by weight of dry gelatin. ToV this solution of gelatin, while at an elevated temperature and still liquid, is added, if desired, a plasticizer such as glycerin, glucose, etc. in sufcient quantity to prevent the final product from being too hard and too brittle and to impart the desired degree of softness or elasticity in the nal product. In this resulting warm solution of gelatin there is emulsied the vitamin-bearing liquid so that there results an emulsion wherein the gelatin solution constitutes the continuous phase and the vitamin-bearing liquid constitutes the dispersed phase. 'I'he water in which the gelatin is dissolved isprevious1y treated', such as by boiling, to remove or expel the oxygen dissolved therein. To make sure that no oxidizing l substances exist ln the gelatin phase, a reducing substance. suiiicient to reduce such oxidizing agents may be dissolved in the latter. For this purpose, I nd vitamin C, 'otherwise known as ascorbic or cevitamic acid, to be suitable. If vitamin C is added in excess of the amount required to reduce all oxidizing substances in the gelatin solution, then, of course, the unoxidized excess becomes a therapeutic agent itself. 'Ihe amount and potency of the vitamin-bearing liquid emulsined in the gelatin solution is based on the potency and liquid content desired in the nal product. It is, of course, to be understood that the quantity of oil must be low enough to be wholly dispersed in the gelatin solution without becoming a continuous phase and without exuding'the liquid oil in the later stages of the process.

Referring now to the drawings wherein an illustrative embodiment of the apparatus constituting one embodiment of this invention is shown and wherein like reference numerals designate like parts, the reference numerals I and 2 designate the vertical and transverse members of a frame formed of any suitable material, such as cast iron, metal and the like, and on which the mechanisms constituting the apparatus, and hereafter fully described. are mounted. The vertical members I of the frame may rest upon any support or foundation or they may rest upon the floor of the building wherein the apparatus is to be used. Rollers 3 and 4 are xedly secured to shafts 5 and 6 respectively which are mounted in bearings 1 carried by the frame. A continuous belt 8,-more fully described hereafter, is trained over and is driven by said rollers 3 and 4.

The belt 8 is provided with a plurality or series of perforations 9 or cavities III constituting molding cavities, the shape and size of which are Vin accordance with and conform to the size and shape of the nished product. For example, the perforations 9 may be polygonal or rectangular or cylindrical in cross-section, as shown in Figures 4 and 5, and the cavities I0 may be in the form of hemispheres or hemi-ovals as shown in Figures 8 and 10 respectively.

The belt may be formed of any suitable material. Metal, such as steel, silver, nickel, etc., or alloys thereof; synthetic resin compositions; cellulosic derivative compositions; appropriate base lmaterials'coated with synthetic resin compositions, cellulosic derivative compositions, etc.; and

regenerated cellulose are several illustrative materials of which the belt may be made.

In one preferred embodiment if the invention, the belt 8 is formed of a material, such as, for example, rubber, which can be distorted as by stretching or by passing over a curved or arcuate surface so that the perforations or cavities thereof may be enlarged, with the consequence that the molded objects `are loosened therein so that they can be expeditiously removed by auxiliary devices or will drop therefrom by the action of gravity.

The composition which is to be molded is supplied to the perforations 9 or cavities I0 in 'the belt in any suitable manner. In the embodiment illustrated, the composition is supplied to the perforations or cavities by means of a hopper Il supported on and carried bythe frame. The hopper is movably and adjustably mounted on the frame so that it may be positioned with respect to the belt as may be desired. For obvious purposes, the hopper is also resiliently mounted.

Though it is obvious thatthe form and shape of the hopper and the means of movably and yieldlngly mounting the same may be eected in various manners and by various means in the present embodiment of the invention, the hopper I I consists of an appropriately shaped body member I2 having a flared inlet end I3 at the top thereof, the hopper normally being open a't the bottom end. If desired, the inlet end I3 may be provided with a cover (not shown). In view of the fact that the composition is to be supplied to the molding cavities or perforations at an elevated temperature, the body member I2 is provided with means to maintain the contents at an elevated temperature. In the form illustrated, the member I2 is provided with a jacket I4, having an inlet I4a and an outlet Mb, whereby steam or some other heating medium of desired temperature may be introduced or circulf" d therethrough.

The hopper II is mounted on the frame through and cooperating with holes of brackets I6 secured at appropriate positions to the said hopper. In the form illustrated, there are four brackets I6, two of which are secured to one side of the hopper adjacent the top and bottom thereof andthe other two being similarly securedI at similar places to the opposite side of the hopper. As shown, each of the brackets I 6 extends beyond the hopper and the extensions are provided with aligned holes through which the post.; l5 pass. The lower ends of the posts I5 are fastened in an appropriate manner to the frame of the machine. Preferably, the lower ends are slidably mounted in bearings, whereby the posts I5 may be raised or lowered as desired.

In one embodiment of the invention, the hopper II is yieldably and adjustably mounted with respect to the belt 8. Though this can be obtained in various ways, in the form illustrated, it is secured at each post I5 through means of a spring I1, the lower end I8 of which cooperates with the lower bracket I6. The upper end I9 of the spring I1 cooperates with the lower end of a sleeve 20. The upper end of the post I5 is provided with a threaded portion 2| cooperating with a nut 22, whereby upon rotation of the nut the tension of the spring I1, through movement of the sleeve 2U, is increased or decreased depending upon the diretcion of rotation of the nut.

The exit end of the hopper, aspreviously described, is open and cooperates with the belt 8. The front vertical wall 23 thereof is designed so that it functions as a squeegee. Thus, when the composition is applied to the belt 8 passing be- Athrough the medium of the posts I5 passing neath the hopper, the squeegee 23 will remove the 65 mounted on the posts I5, the same is also'movable with respect to the belt 8, the degree of movement depending, of course, on the movement of the nuts 22 and sleeves 20 on the posts I5.,-

If desired, a squeegee (n'ot shown) may be provided in advance of the hopper I I. Such a squeegee may operate in place of or in conjunction 'with the squeegee 23.

Instead of making the squeegee 23 an integral part of the front wall of the hopper, a slide member functioning as a squeegee may be adjustably, movably and resiliently mounted on the fron wall of the hopper in any known manner or as will be apparent to one skilled in the art.

As previously explained, the composition is of a 'type and naturewhieh sets upon cooling and the invention contemplates means to Vaccomplish this expeditiously. Various means may be utilized to secure the desired results. For example, I may provide appropriate cooling means which will act directly on the composition in the perforations or cavities in the belt. Likewise, I may provide means which will chill the belt and thereby transmit the cooling effect to the compositions in the perforations or cavities. Also, I mayemploy combinations of the aforementioned means. The 'chilling means may chill the mold cavities or perforations or belt prior to, simultaneously with, or after the application of the emulsion.

Various chilling mechanisms may be utilized and the invention is not restricted to any particular form or type. In one embodiment of the invention, the desired results are secured by use of a cooler 24 (diagrammatically .illustrated in the drawings) in cooperative relationship with the belt 8, which consists of a tank in which a previously fluid medium, previously chilled to the desired temperature, is introduced through the inlet 25 and from which it passes through the cooler chamber 24 and out through the outlet 21.

The cooler 24 may be opened at the top, in which case the belt 8 and a support 28, hereafter described, constitute a moving cover.

It is to be noted that in the illustrated embodiment the cooler 24 extends beyond and underneath the hopper Il so that the belt 8 is in a more or less chilled state when the emulsion is applied to it.

When the belt is provided with molding cavities, it is unnecessary to-provide any means of supporting or maintaining the composition therein. However, when the molding cavities consist of perforations, it is essential that there be provided some means of support to maintain the composition in the perforations until it has been set in the desired form. With this in view, -the invention also contemplates the provision of a belt 28 which traverses beneath the belt containing the perforations. 'Ihis belt is a continuous one and travels at the same rate of speed as the belt 8. It travels over the roller 3, previously described. and also over a roller 29 disposed intermediate the rollers 3 and 4. The roller 29 isflxedly secured to a shaft 30 which is rotatably mounted in bearings (not shown) on the frame of the machine. The

supporting belt is formed of a material which possesses a high coefficient of heat transfer.

Thus, when this belt is subjected to the cooling operation of the cooler, it is chilled and it effectively transfers the cooling effect directly to the belt 8 and directly also to the composition in the molding prforations, when a belt of the type illustrated in' Figures 4 to 7 inclusive is utilized.

. molded articles may be` removed therefrom in any convenient manner. For example, the belt may pass beneath a brush 3| which rotates in contact with said belt, the action of the brush being suf-- cient to eject the molded articles from the belt into a collecting hopper 32. If desired, instead of a brush 3 I there may be provided a roller having pins similar to ejector pins suitably disposed around its periphery, so that it may contact with and remove the molded articles coming in contact therewith.

When the molded articles are formed in cavities in contradistinction to the perforations, the belt may be caused to pass around surfaces, whereby it is distorted and the molded articles loosely held therein. Thereafter, the molded materials may be removed by easy brushing of the belt. This embodiment is shown in Figure 3, wherein the belt containing the molded articles passes around the roller 4 and thence over rollers 33 and 34. Adjacent the roller 34 there is provided a brush 35 which brushes the molded material from the belt and the removed products are received in a. hopper 36. Thereafter, the belt passes over the roller 31 and continues its course over the guide rollers 38, as illustrated. This embodiment may also be used when perforations constitute the molds in the belt.

In order to inhibit the molded materials from yadhering to the molding cavities or perforations,

with the consequence that the removal thereof is diilicult, the invention also vcontemplates applying to the belt 8 at some stage in the travel thereof, prior to the application of thecomposition, a substance which functions in the nature of a lubricant. Various substances may be utilized. I have found that oils, such as castor oil or other hydroxylated oils, are admirably suitable for this purpose.

The lubricant, previously described, may be applied to the belt at any convenient point in its path of travel. In the form illustrated, oil is applied to a closed vessel 39 in which rotates a brush 40, the amount of oil being such that the lower portion of the brush is immersed therein and, as it rotates, it applies it on to the surface of the belt. The level of-the lubricant in the vessel 39 may be maintained at its desired height in any Well-known manner, as, for example, the barometric feed 4I.

When a lubricant of the type previously mentioned is used after the molded articles have been collected, they are subjected to a washing to remove any adhering lubricant from the product.

The rollers 3 and 4 may be separately driven, or the roller 3 may be driven by any suitable drive (not shown). In either event, the brush 40 is driven by means of a sprocket 42 trained over a sprocket wheel 43, 'secured to the shaft 5,

and a sprocket wheel 44, secured to the shaft on' which the brush 40 is mounted. 'I'he roller 29 is driven by means of a sprocket chain and sprocket wheels 46 and 41 carried by the shafts 6 and 30 respectively. 'I'he brush 3.5 is driven by the roller 28 through a sprocket chain 48. The other mechanisms or rollers may be connected by sprockets, chains, gears, etc. so that their movementor rotation is synchronized with thev rollers 3, 4 and 29. fl'

Though the invention has been specifically described in connection with gelatin tablets containing vitamin-bearing liquids imprisoned therein, it is to be understood that` it is equally applicable to tablets containing vitamin-bearing liquids in which the carrier is formed of a colloid matrix other than gelatin. Likewise, the invention is applicable to-any composition which sets upon cooling and which can be molded as herein described, such as, for example, candy, cometics, plastics, etc`. y

Although certain preferred embodiments of the invention have been disclosed for purposes of illustration, it is obvious that various changes and modifications may be made therein as will appear to a person skilled in the art. lThe invention is to be limited only in accordance with the following claims when interpreted in View of the prior art.

I claim:

1. An apparatus which comprises an endless belt having molding perforations formed therein, and adapted to receive the composition to be molded, a second endless belt formed of a material having a high coeicient of heat transfer cooperating with the first-named belt and constituting a support to maintain the composition in Athe perforations, means toA chill the second belt, means to separate the two belts, and means to remove the molded products from the perforations in the first belt.

2. An apparatus which comprises an endless belt formed of an elastic material and having molding perforations formed therein and adapted to receive the composition to be molded, means to apply a lubricant to said perforations, a second endless belt formed of a material having a high coecient of heat transfer cooperating with the rst-named belt and constituting a'support to maintain the composition in the perforations, means to chill the second belt at least while it functions as the support, means to separate the said belts, and means to distort the first-named belt wherebythe molded products will be loosened. )15

JAMES ALBERT RAYNOLDS, JB.

Images