US1102374A - Apparatus for forming medicinal tablets. - Google Patents

Description

H. E. WHITAKBR & J. M. MAUDONALD.

APPARATUS FOR FORMING MEDICINAL TABLBTS.

APPLICATION PILBD MAR. B, 1908. 1,102,374 Patented July 7, 1914.

2 SHEETS-SHEET l.

fn z/en for es/l'l. Mar 0`Da 1d sgi l THE NORRIS PETERS CD.. PHOTO-LITHO WASHINGTON. D. CC

H. E. WHITAKBR & J. M. MAUDONALD.

APPARATUS FOR PORMING MEDICINAL TABLETS.

APPLICATION FILED MAB. 9, 190B.

Patented July 7, 1914.

Winesses [2276/2 for.

#mg/E WI fale/ James/1411461600170 2d,

,' E` STATES PATET FFIDE- HENRY E. WHITAKER AND JAMES M. MACDONALD, OF DETROIT, MICHIGAN, ASSIGN- ORS T0 PARKE, DAVIS t COMPANY, 0F DETROIT, MICHIGAN, A CORPORATION `OF` MICHIGAN.

APPARATUS FOR FORMING MEDICINAL TABLETS.

Specification. of Letters Patent.

Application filed March 9, 1908.

Patented July 7, 1914!. sei-iai No. 420,097.

To all 107mm 'it may] concern Be it known that we, HENRY E.' lll/'Hirn itin: and Jairns M. MACDONALD, citizens of the United States oit' America, residing at Detroit, in the county of lVayne and State oit lyliichigan, have invented certain new and nse'tul Improvements in Apparatus for Forming Medicinal Tablets, of which the following is a specification, reference being had thereinto the accompanying drawings.

rlhe invention relates to machines for forming tablets, and it is the special object of the invention to obtain a construction which is adapted for forming medicinal tablets either friable or hard compressed.

To this end the invention consists in certain features of construction as hereinafter set forth.

In the drawings- Figure 1 is a vertical longitudinal section through the machine; Fig. 2 is a cross-section substantially on the line ot Figil, certain `parts being o-mitted. y

In the present stateo'f the art medicinal tablets` of the soft riable variety ai'e formed by a hand process, while the compressed tablets `are formed mechanically. The hand process is one necessitating' the` mixing of the dry ingredients with alcohol to :form a plastic compound, the iilling of the perforated mold plates with this plastic substance by the use of a spatula, the drying and har.- dening of the material in the mold cavities by dusting in dry powder over the surface of the plate and scraping it in with the spatula, and inally the ejection of the mold ed tablets from the plates. This process is a slow one, requiring a certain degree of skill on the part of the operator and necessitating the use of alcohol as amoistening agent. On the other hand, the compressed tablets, while they may be 'formed by mechanically driven and automatically oper ated presses, require `for their manufacture' a granulated materiah and this necessitates a long and expensive process of the treat nient of the ingredients before the material is ready forl the press.

With the machine forming the subject matter of the present invention the tablets may be formed from the mixed ingredients by slight moistening of the mixed'dry materials, and for the moistening agent water may be employed,`instead of alcohol.

Broadly considered, the machine comv prises means -tor distributing the material over the mold plates, together with means :for niecluinically pressing the distributed material into the mold cavities and` for scraping ott' from the surface the surplus material.

The machine further comprises mechanisin for ejecting the tablets from the mold cavities aiiih'u'licre the'eoiupressed tablets areto be formed, further includes compress' ing dies and operating ii'iechanisni therefor.

One oit' the difficulties encountered in the manipulation ot' the materials oi which the tablets ai'e formed is the tendency to adhere i.

saine degree of compression. To ineetthese cond1t1ons,the machine comprises as` one of its essential features mechanism 'toi' moving a blade a'portion oil which is inclined over the surface of the mold plate upon which the tablet `.material has been deposited while said,

plate is resting upon a bed or tabl e, the operation of the blade being to simultaneously force the material into the mold cavities and to sera ic'o'fl the sur ilus material. .ln ier` yforming this function there is a tendency to coniifiress the `material to a greater degree upon the side ot' the mold cavity toward which the inclined blade `is moved, and to avoid this result a second bladehavingan oppositely inclined portion is preferably employed, this being moved over the plate in reverse direction. the blades and the mold plate may be accomplished in different ways. but preferably is effected by mounting' the blades upon revoluble members and by feeding the plates` beneath said revoluble members.

ln detail A is a suitable frame or bed provided with guii'leways B for the movable mold plates C. These plates are fed along the guides by suitable feeding mechanism, such as the `i'olls D D', which frictionally engage the plates as they are intro duced at one end of the machine. feeding them over the bed and propelling the plates to advance as they are disengaged from the rolls. Adjacent to the i'olls D D is ai'- ranged a hopper, or other' receptacle, lil

The relative movement of` containing the material forming the tablets. This material has been previously mixed and moistened and the hopper E preferably contains an agitator, such as the revoluble member F, for assisting the uniform deposit of the material on the mold plates. Beyond the member F is a filling and distributing roll Gr which gages the height of the material deposited on the plates, and also presses it into the mold cavities. The surface of this roll is of any suitable material, such for instance as celluloid, to which the moistened material will not readily adhere.

H and l are two oppositely revoluble shafts extending across the bed above the path of the mold plates and journaled in suitable bearings in the frame. Each of these shafts has secured thereto a series of radially extendingplates J, these being preferably formed of resilient material and being preferably also slightly curved. The blades carried by the shafts H travel in the same direction as the mold plates, but at a higher rate of speed, while the blades on the shaft l travel in the opposite direction. Thus the former will press the material which covers the surface of the plates downward and into the mold cavities, and will then scrape over the surface of the plates to remove the surplus material, throwing it forward or in the direction that the mold plate is traveling. The blades upon the shaft I have a similar action upon the material which has been thrown forward by the other blades, and the combined action of the two sets of blades is to accumulate the surplus material in a triangular pocket between the shafts H and l. The material is prevented from being thrown over the shafts H and and the blades are also cleaned by Scrapers K, which are arranged to bear upon each of the blades, as they rotate to disengage any adhering material therefrom.

The plates after passing beneath the shaft I are fed forward at an accelerated speed by a pair of feed rollers L L, and this is for the purpose of permitting each plate to remain stationary for an interval during which the tablets are ejected. The ejector mechanism comprises a vertically reciprocating head M, which is provided with downwardly extending pins N thatA register with the mold cavitiesy in each of the mold plates C, during the interval in which it is stationary beneath the head M. The descent of this head will cause the pins N to force the tablets downward from the mold cavities, and at this point the bed of the machine is cut away to permit the disengaged tablets to drop upon a receiving plate or carrier O.

Vhere oval or other fashioned tablets are to be formed this operation is effected while the material is still in the mold cavities and after the plates have passed beyond the Scrapers. lf desired, this forming mechanism may be combined with the ejector mechanism, the head M having a portion M thereof for holding one of the compression dies and a second compression die P being arranged beneath the plate and being moved forward as the head M is moved downward.

Any suitable form of gearing may be employed for driving the various parts of the mechanism above referred to in proper timingrelation. As shown, motion is first communicated to the main drive shaft Q, by a suitable belt engaging tight and loose pulleys upon this shaft. This shaft Q drives the rolls L L through the medium of a gear train R, and drives the shafts H and T through a gear train S. The rolls D D are driven through the gear train S and a sprocket and chain connection T, and the roll G is driven from the shaft of the roll D by a sprocket or belt connection U. The ejector and compressor mechanism is operated through a gear train V from the shaft Q, which drives a shaft W, having eccentrics X and Y thereon, which are respective-ly connected to operate the heads M and l.

In operation, the moistened material is placed in the hopper E and is driven over the plates as they are fed forward by the rolls D D', while the roll G, which is preferably driven at the same speed as the plate, gages the depth of the deposit and presses it down to fill the mold cavities. is the plates continue their forward movement, they first pass beneath the shaft H and into the path of lthe rotating blades J carried thereby. These blades are curved, as described, and rotate to press the convex surface against the material on the plates forcing it downward into the mold cavities until the edge of the blade l comes in contact with the upper surface of the plate C. The blade will then be caused to scrape over the surface of the plate, the resiliency of the material of the former permitting this operation. A similar action takes place as the plates C are fed beneath the shaft l, the only difference being that in the first casethe pressure exerted on the material is toward the forward side of the mold cavity and in the latter case toward the rear side thereof. The effect will be to produce a uniform density in all portions of the tablets, and the operation of the blade el on the shaft I will produce a smooth upper surface. The lower surface of the tablet is formed by sliding over the bed or table upon which the plates C are moved, and thus when the ejector' mechanism is reached the tablets are in condition for disemqagement.`

lt is to be noted that the operations performed by this machine differ from those of the usual hand processi ln the latter, the

i to dust dry powder over each face ofthe dry powder.

mold plate working it into the mold cavi-` ties with the spatula, and `thereby drying and hardening theitablets before they can be ejected. In theoperationof the machine, the material hasbut a limited amount of moisture therein, so that it can only be forced into the mold cavities by the exertion of considerable i pressure. produced by the action of the blades and, as they are traveling at a higher rate of speed than the movement of the plate C, a series of these blades will successively operate upon the material for each row of tablets. Thus, afterthe cavities `are filled, and the surplus material scraped off, the tablets are in condition to be immediately ejected without `requiring the intermediate step of dusting in The operation of the blades J J in the opposite direction causes the accumulation of a `quantity of the material therebetween, and to remove this material a transversely `evtending j screw conveyer or equivalent device Z is arranged between the shafts H and I. This in operation will carry away the accumulated material which may be returned to the hopper E.

What we claim as our invention is:

l. In an apparatus for forming medicinal tablets, a mold. plate having a series of mold cavities therein, a roll extending transversely of the mold plate for depositing a uniform layer of material over the latter, a blade,`

and means for operating said blade to scrape and knead the material into the mold cavities.

2. In an apparatus for forming medicinal tablets, a mold plate having a series of mold cavities therein, means for depositing material upon said plate, a plurality of revolving blades, a portion of said blades being inclined in the direction of said blades travel for pressing and scraping the material into the mold cavities.

3. The combination with a mold plate having a series of mold cavities therein, of means for depositing the material upon said plate, means for scraping the material in opposite directions over said plate, and means for removing the surplus material accumulated by said scraping means.

l. The combination witha mold plate having a series of mold cavities therein, of a bed over which said plate is fed, means for depositingthe material upon said plate, a pair of oppositely rotating members above said bed, Scrapers carried by said rotating members and moved thereby across said plate when moved over said bed to force the l material `on i said This pressure is f each mold `depthlof theimaterial thus deposited, oppoplate into said mold cavities, and means for removing the surplus `material accumulated by said Scrapers,

5. The combination with a bed, of a series ofmold plates adapted to be successively fed over said bed, j each `plate being provided with` a series of `mold cavities, means for de-` positing the material upon said plates, a revolving `blade forforcing the deposited material into the mold cavities, and for removing the surplus material, and an ejector for idisengaging the molded tablets from said plates` 6. Thecombination with a bed, of a series of mold platesZ each provided with a series of mold cavities, means for feeding 1 said.

mold plates successively ovei'isaid bed, means for depositingr material on the surface of plate, a `gage for determiningthe sitely revolving blades for pressing and scraping the material into `the mold cavities, and means for ejecting the molded tablets.

` 7. The combination with a mold plate having a series of mold cavities therein, of means for depositing material upon said plate, a roll for pressing thejmaterial against the plate and into the mold cavities thereof, a blade having an inclined portion, and means for moving said blade over the surface of said plate to further press the material into the mold cavities and removing the surplus material from the surface of the plate.

8. The combinationwith a mold plate having `a series of apertures extending therethrough, of a bed, means for feeding said plate over said bed, means for depositing the material on the surface of said plate, means for pressing the deposited material against the plate to force it into the mold cavities thereof, means for drawing an inclined scraper over the plate to further force the material into the mold cavities and to remove the surplus material, a forming die for fashioning the molded material while still in the mold cavities of said plate, and an ejector for disengaging the completed tablet.

`9. The combination with a bed or table, of a mold plate having a series of mold cavities therein, means for feedingsaid plate over said bed or` table, means for depositing material upon said plate, a roll for pressing the deposited material against said plate and into the mold cavities thereof and for gaging the depth of the material upon the plate, a rotary member having a series of Scrapers successively drawn over the surface of said plate, a forming die for fashioning the tablets While in the mold cavities and an ejector for disengaging said tablets.

10. The combination With a mold plate having a series of mold cavities therein, of means for depositing a uniform layer of material over said plate, a series of revolving means for feeding said. mold plate across thel path of movement of said yblades and transverse thereto, for the purpose described.

l2. The combination With a movable mold plate haing a series of mold cavities therein, of a revolving blade partially inclinedl in the direction of travel of said blade for pressing and scraping thel material into the mold l cavities.

13. In an apparatus for forming medicinal tablets, a mold plate having a series of l Imold cavities therein, a plurality of revolving blades partially inclined in the direction of travel `of said blades for pressing and scrapingthe material into the mold cavities.

lll. In anapparatus for forming medicinal tablets, a mold "plate having a series of mold cavities therein, means for depositing a uniform layer of material over said plate, a blade for forcing the material into the mold cavities, means for moving said blade over the surface of said plate in inclined relation thereto, and an elector for disengaging the tablets from .the mold cavities.

In testimony whereof We affix our signaytures in presence of tivo Witnesses. Y l

HENRY E. WHITAKEB. 'JAMESM- MACDONALD. Vitnesses to both signatures:

NELLIE KINSELLA, JAMES?. BARRY.

ACopies of this patent may be obtained for ve cents*l each, by addressing the Commissioner of latents,

Washington, I). G."

Images