GB2149377A

GB2149377A - Forming tamper-resistant tamper-indicative capsules

Info

Publication number: GB2149377A
Application number: GB8421248A
Authority: GB
Inventors: Donald N Maclaughlin; Vincent E Fortuna
Original assignee: Cosden Technology Inc
Current assignee: Cosden Technology Inc
Priority date: 1983-08-26
Filing date: 1984-08-21
Publication date: 1985-06-12
Also published as: FR2550941A1; GB8421248D0; DE3430764A1; AU3188884A; BE900398A; IT1175616B; IT8422370A0

Abstract

The two telescoping halves of a capsule made of a thermoplastic material, such as rigid gelatin, are securely joined to one another. In one embodiment this involves partially detelescoping the capsule halves, rendering a portion of the capsule in the previously telescoped region tacky, eg by heat or solvent, and retelescoping the halves with relative spining or axial oscillation of the halves. The halves may also be spin welded.

Description

SPECIFICATION Methods and apparatus for forming tamper resistant tamper-indicative capsules, and articles formed thereby BACKGROUND OF THE INVENTION The present invention relates generally to methods and apparatus for sealing medicinal capsules and more particularly involves methods and apparatus for spin-welding rigid gelatin capsule sections together to form sealed tamper-proof and tamper-indicative consumer items.

The present invention also relates to medicinal capsules and more particularly spinwelded rigid gelatin capsule sections which form sealed tamper-proof and tamper-indicative consumer items.

Conventional methods of packaging powdered consumer products such as aspirin, headache powders, and cold remedies involve the packaging of individual doses of these medicinal compounds into telescopic tubular capsules manufactured from "rigid gelatin".

Each such capsule contains a single dose of the subject medicine and consists of a top tubular section which is slipped over in relatively snug-fitting engagement a bottom tubular capsule containing the medicinal compound. Experience has shown that the conventional capsules are very susceptible to tampering by the general public while sitting on the retailers' shelves. Conventional means for preventing such tampering involves the use of elaborate closures for the medicine bottles.

Unfortunately, most if not all of these so called tamper-indicative bottle closures can be defeated by ingenious persons. Even in the case where the bottle closures are difficult to defeat, after the bottle has been opened its contents are still vulnerable to tampering by persons who have access to the bottle. For example, in public health clinics, school clinics and other areas where the public has general access to such medicines, the tamper indicative bottle closures do little to prevent tampering with the capsules after the bottle has been opened.

The present invention overcomes these difficulties of the prior art means of preventing medicine tampering by providing apparatus for sealing each individual medicine capsule.

The seal achieved with each capsule is an integral seal strong enough to require destruction of the capsule to expose the contents thereof. Such destruction is a clear indication to a subsequent user that the capsule has been tampered with.

SUMMARY OF THE INVENTION The present invention describes means for tightly sealing together telescopic ends of individual capsules containing powdered medicinal compounds. The invention embodies a combination steam jet and spin-welding system to provide rapid mass production sealing of individual capsules.

The present invention comprises a process for forming tamper resistant or tamper-indicative capsules comprising two telescopable capsule halves made of rigid gelatin or any other thermoplastic material, the bottom half being filled with the consumable product and the upper half being in close fitting telescopic engagement over said bottom capsule, said process comprising exposing portion of an engagement zone in the telescopic region between said capsule halves; tackifying the gelatin in at least a portion of said exposed zone; spinning at least one of said capsule halves in relation to the other said half; and, combining said capsule halves in fully telescoped engagement during spinning thereof.

The apparatus for carrying out said process comprises an orienter for placing telescopically joined capsules in a predetermined, desirable vertical orientation; upper and lower gripping means for gripping top and bottom capsule halves, respectively; means for partially detelescoping said capsule halves; tackifying means for tackifying a segment of the telescopic surface of at least one of said capsule halves; means for rotating said tackified capsule half with respect to said other capsule half; and, additional means for retelescoping said capsule halves together simultaneously with said rotating means.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a side-elevational view of a set of capsule components prior to assembly.

Figure 2 illustrates a cross-sectional side view of an assembled capsule.

Figure 3 illustrates a cross-sectional side view of a capsule which has been partially detelescoped.

Figure 4 illustrates a cross-sectional side view of a capsule that has been rejoined and sealed according to the present invention.

Figure 5 illustrates a side elevational view of a capsule welding apparatus.

Figure 6 illustrates a top view of the apparatus of Figure 5.

Figure 7 illustrates a close-up illustration of one spin-welding station.

Figure 8 illustrates a schematic view of the camming assembly of the spin-welding apparatus.

Figure 9 illustrates a schematic view of the orienter assembly of the apparatus.

Figure 10 illustrates a cross-sectional side view of the steam jet assembly of the invention.

Figure 11 illustrates a schematic diagram of the process generator and its control system.

Figures 12-14 illustrate different views of the vacuum chuck assembly of the present invention.

Figures 15 and 16 illustrate another em bodiment of the invention utilizing a displaced source of radant energy for fusing the capsules together.

Figure 17 illustrates yet another embodiment of the invention utilizing solution tackification to fuse capsules.

Figure 18 illustrates still another embodiment of the invention in which abrasion-augmented friction welding is utilized to fuse capsules together.

Figure 19 illustrates an embodiment utilizing capsules having surface irregularities for spin-welding.

Figures 20 and 21 illustrate a heated wire fusion embodiment of the invention.

DESCRIPTION OF THE PREFERRED EMBODI MENTS Referring now to Figures 1 through 4 there are illustrated in enlarged cross-sectional detail the various stages of the telescoping capsule assembly. In Figure 1 a gelatin capsule 101 comprises a top or upper cylinder 102, and the bottom or lower cylinder 103 which has been filled with a powdered medicinal compound 104. The particular capsule components 102 and 103 may be of the conventional type currently in use today. These capsules comprise a pair of generally cylindrical tubular capsule sections made in a cylindrical circular shape of a rigid gelatin ana eacn having a rounded end. The two components generally are very close in size and feature a tight, friction fit therebetween. There is just enough clearance or tolerance in the sizes to allow a sliding movement between the cartridges after they have been filled with powder.

Figure 2 illustrates a conventional cartridge after it has been completely telescoped into its closed position. This is the orientation of the capsule as it is placed into the apparatus of the present invention. In the present embodiment the invention is directed to an "after market" or add-on type of system to be utilized with the capsule-fillers currently in use. In other words, the present invention in its disclosed embodiment is intended to be added to the end of a capsule filling line between the filling system and the bottling apparatus. In a separate embodiment it is visualized that the present invention could be integrated into a filling system and could thus reduce by one or two steps the practice of the present invention.Notwithstanding the aforementioned reference to an integrated system, the present embodiment will be described as an add-on system to be placed in line with a manufacturer's present equipment. Thus the process will be described in relation to the steps of taking a finished capsule as indicated in Figure 2 and partially separating the capsule, then rejoining the capsule in a spinwelded mode. Thus Figure 2 illustrates the capsules as they arrive at the apparatus described in this invention.

Figure 3 shows a cross-sectional side view of the cartridge of Figure 2 after it has been securely located in the spin-welding apparatus of this invention and has been separated by a distance denoted by "Z" the remaining telescopic engagement of the capsule components in Figure 3 being signified by the symbol "E". The ratio of separation ''Z'' to engagement "E" during the spin-welding preliminary stage is approximately 3 to 2 or, put in another way, the capsule is de-telescoped approximately 60 percent of its original engagement dimension. While the capsule is held in the orientation of Figure 3 the steps hereinafter more particularly described are performed on the capsule and it is re-engaged at a predetermined specific instant after being impinged with a thin steam jet, and spinwelded.Figure 4 illustrates the re-engagement of the capsule components immediately subsequent to the steam impingement and spinwelding steps. Figure 4 therefore represents the final sealed configuration of the tamperproof and tamper-indicative capsule.

Referring now to Figure 5, one preferred embodiment of the system for performing the present invention is disclosed in schematic view therein. In Figure 5 the basic system 201 comprises a base 202 upon which is rotatably mounted a welding wheel 203 and a pickup wheel 204 (Figure 6). On a spindle above weld wheel 203 is located a feed system 205 comprising a mounting spindle 206, a ladder feeder (conveyor) 207, a bulk feed trough 208, a slow moving felt or padded buffer wheel 209, an orienter 210, and a feed tube 211.

A vibrator 213 is attached to the bottom side of trough 208 to provide vibration of the trough to facilitate movement of capsules downward into engagement with buffer wheel 209. Wheel 209 is mounted in trough 208 by means of a spindle or shaft 214. Likewise orienter 210 which comprises a set of parallel sheaves or "V-pulleys" is mounted on a spindle or shaft 215.

Rotary motion is applied to those rotatable elements of the present invention by means of a drive motor 216 coupled through a gear reducer 217 to spindle 206. A top rotary joint 218 is rotatably connected to drive motor 216 through shaft 206 and serves to rotate in a clockwise direction as seen from above. A series of upper weld mandrels 219 are attached to rotary joint 218 by connection means (not illustrated). Weld mandrels 219 are also vertically reciprocal and are positioned vertically by the action of inbound rollers 220 which engage in cam slot 221 formed in a stationary cam wheel 222. The weld mandrel 21 9 comprises a bearing mounted weld head 223 rotatably mounted on an elongated mandrel shaft 224 which in turn is suspended from a cross-mandrel shaft 225.Cross-mandrel shaft 225 has the afore mentioned inboard roller 220 and an out board roller 230 rotatably mounted at each end thereof. In this particular preferred em bodiment there are sixty weld mandrels 219 located radially outward from rotary joint 218 in relative equispaced configuration.

The upper weld assembly, comprising com ponents numbered 204 through 230, are suspended by a main pedestal column 231 centrally located therebelow and extending downward to the lower weld assembly. The lower weld assembly generally comprises a weld wheel 203, a bottom rotary joint 232, a lower shroud 233, a base pedestal 234, and a control console cabinet 235. Control console 235 which supports the entire weld apparatus may be mounted by wheels 236 to provide portability of the system. A control panel 237 is located on the front surface of cabinet 235 to allow establishment of process control variables in the operation of the system.

Figure 6 is a top view of the apparatus of Figure 5. The view of Figure 5 is taken along section A-A of Figure 6. In Figure 6 the capsule weld system 201 shows a top dome cover 240 below which is located a series of weld mandrels 219 drawn in phantom to illustrate typical locations below the upper rotary assembly. A drive system 241 is arranged in proximity to weld stations 219 and comprises a driven pulley 242 and a driving pulley 243. A second driven pulley 244 is also located in close proximity thereto. A drive belt 245 is stretched over the three pulleys and also is arranged to engage mandrels 219 along an arcuate section 246. This arcuate section comprises approximately 60 to 70 degrees of the entire 360 degree circular arc of the upper rotary system. The spinner system 241 is shown also in Figure 5 in partial cross-sectional side view.The drive motor 247 of Figure 5 serves to drive the driving pulley 243 and to move the drive belt 245 about the three pulleys. A housing 252 protects the spinner drive assembly. Figure 6 also illustrates the arrangment of a vacuum pump 250 to provide operating vacuum for maintaining the capsules in their orientation in the system. Discharge wheel 204 comprises a circular plate having capsule indentations 251 formed in the outer wall thereof. A water storage tank 253 is provided for storing a supply of distilled water for the welding system. An electrical cabinet 254 is also provided for housing the electrical components of the present system.

Also in Figure 6 a more detailed construction of the feeding system comprising the conveyor 207, the trough 208, the wheel 209, and the orienter 210 is illustrated. The trough 208 is provided with a series of parallel longitudinal channels 255 cut or formed in the bottom of trough 208. Each channel is arranged to orient the capsules in a longitudi nal direction with respect to trough 208. At the end of trough 208 a soft padded buffer wheel 209 rotates to draw the capsules into the orienter 210. The orienter 210 comprises a set of six pulley-like sheaves 256 each having a profile generally illustrated in Figure 9. In Figure 9 one of the orienter sheaves 256 is illustrated having a profile of a narrow inner channel 257 and a wider outer channel 258 located radially outward from inner chan nel 257.The construction or orientation of wheel 256 is such that as the capsules pass over the top of orienter 210 the lower portion of the capsule will pivot inward into the restricted channel 257 forcing the upper capsule section into the upper or top portion 258. Thss is achieved by making the inner channel 257 smaller than the outer diameter of the capsule top thereby preventing entrance of the capsule top into the lower channel. Thus the combination of channels 255 and sheaves 256 serves to orient the capsules first in a longitudinal direction and then with respect to the large and small ends into a vertical orientation. From sheaves 256 the capsules slide into a series of feed tubes 211, one of each being located directly below the lip of each sheave 256.Each feed tube 211 curves downward into a vertical feeding position directly above a capsule cavity on weld wheel 203 as illustrated in Figure 5. It should be noted that for purposes of simplicity and clarity a single feed tube 211 is illustrated in Figure 5 yet in the preferred embodiment a series of six such tubes in fact are used.

In addition to the various aforementioned assemblies and subassemblies illustrated in Figure 6 associated with the present system, one key subassembly is the process generator 260 located radially inward from weld mandrels 219 across from spinner drive system 241. The process generator 260 is more clearly illustrated in Figure 10 and comprises a steam jet generator having an electrical flash element 261 located in a tubular housing 262. The flash element 261 is heated by electrical power preferably 220 volts supplied to contacts 263. Element 261 is a resistance heater driven by the 220 volt power source and utilized to flash distilled water which enters through supply line 264 and is maintained in primary fluid compartment 265. A pair of alternating offset baffle plates 266 and 267 are located in tube 262 to prevent liquid water from escaping chamber 265.A narrow escape path indicated by flow arrows 268 is arranged between offsetting plates 266 and 267. Steam is allowed to escape through jet nozzle 269.

A blowout plug 270 is located in the steam compartment 271 of steam generator 260 and is adjusted at around 5 psi to prevent over-pressurization of the generator system. A high level liquid probe 272 is located in the wall of compartment 265 and a low-level probe 273 is located in the lower surface of compartment 265 to indicate a low fluid level.

Petcock 274 is also located in the lower end of chamber 265 to allow drainage of fluid from the steam generator for maintenance purposes. A temperature probe 275 projects inwardly into the lower portion of chamber 265 from back wall 278. A temperature control wire 276 leads from temperature probe 275 to the control panel for the system. It should be noted that steam jet 269 is directed at a gelatin capsule in the region of "Z" as illustrated in Figures 3 and 4. The position of steam generator 260 is schematically illustrated in Figure 6, as previously mentioned, radially inward from the weld mandrels 219 and the spinner drive system 241. The steam jet 269 is directed radially outward to impinge capsules held in weld heads 223. Preferably a source of vacuum is supplied down each weld spindle 224 to provide a source of vacuum for head 223 to grasp capsules therein.Likewise a source of vacuum is supplied upward through weld wheel 203 to grasp the capsule bottom sections held therein.

Operation of process generator 260 may be established. on a purely mechanical, cammed basis actuated by cam members contacting one or the other of the rotating elements (203, 218, 242, 243, 244, etc.). Alternatively, the process generator can be activated manually by a separate on/off electrical switch. Or it can be in a constant-on orientation by tying in the power supply contacts 263 to the same switch supplying motor power to the spin-welding assembly, thus insuring that steam is generated constantly at all times while the spin-welding assembly is on.

Preferably, process generator 260 is activated by an automated control system utilizing solid state control elements. Also, one preferred embodiment adds a high-voltage steam ionization feature to obtain better distribution of steam impingement on the capsules.

Figure 11 illustrates schematically both a solid state control system and an ionized steam process.

The system disclosed in Figure 11 consists of steam generator 260 with flash heating element 261, low and high fluid level probes 273 and 272 respectively, and water supply line 264. In addition to these previously described elements, the system further comprises a sterile water storage tank 212 having a coiled condensate return line 277 therein connected to the spin-welder capsule assembly area. Tank 212 has a low-water-level logic probe 282 projecting through the wall thereof and communicating with a solid state process controller 228 via electric conduit 283. The process controller also receives signals from the high and low level probes 272 and 273 by leads 284 and 285 respectively.

Heater 261 is a dual element unit with circuitry located in box 229, receiving power from a solid state power controller 238 through leads 286. Controller 238 is in turn actuated by signals from a solid state temperature controller 239 connected by leads 287 thereto. An input signal to the temperature controller is generated by probe 275 and communicated via lead 288.

Sterile distilled water is pumped to the process generator 260 through pump 290 which is supplied with water by supply line 289 leading from the bottom of tank 212. A one-way check valve 291 prevents backflow of fluid from the process generator when pump 290 is turned off. Pump 290 may be turned on and off by a signal from process controller 228 communicated via line 292. A 15 psi pressure relief valve is located in the steam chamber of the process generator to prevent overpressurization thererof. The temperature probe 275 is preferably a type "J" thermocouple.

During operation, sterile distilled water is delivered to the steam generator 260 by pump 290 which is controlled by process controller 228 in response to readings from the probes 272 and 273. Checkvalve 291 prevents pressurized stream from backflushing through pump 290. Temperature control in the process generator 260 is achieved by the closed-loop system comprising the temperature controller 239 and the solid state power controller 238. As described previously, baffles 266 and 267 strip excess moisture from the steam generated by flash heater 261.

The sterile steam emitted from generator 260 then flows through line 269 to the injector valve assembly 249 which is electrically controlled by the process controller 228, via an electrical lead (not shown), to bypass steam into return line 277 while the spinwel- der is not in its operating mode. This would occur, for example, when starting up the welding operation and getting all the components up to operating temperature.

Once the spinwelder begins welding capsules, the controller signals valve assembly 249 to switch from its bypass mode into its injection mode and steam is then supplied to the metal injector needle 259. A ground plane target 294, which generally consists of a grounded target, is displaced a distance E from needle 259. A vacuum source 295 is connected to a collector 296 to prevent overspray of emitted stream and collect all moisture not impinging capsules in gap E. A high voltage is supplied via generator 248 to needle 259 to produce an ionized field across gap E. The steam spray emitted into the ionized field thus wraps around the capsule better and is thereafter attracted to the grounded target in the vacuum collector. This greatly reduces the loss of sterilized steam and prevents contamination thereof, thus allowing a recycling of the sterile distilled water indefinitely.A steam/water return line (not shown) from collector 296 to tank 212 recycles oversprayed steam and water not impinging capsules during the spinwelding operations.

Figures 12-14 describe in more particular detail one preferred embodiment of the gripping means for securing the capsules to be welded in the weld wheel 203. In this embodiment, the gripping means also serves as a perpendicular alignment means for the capsules. Figure 12 is a top view and Figure 13 is a bottom view of a gripper system. Figure 14 is a detailed cross-sectional side view of a gripper system. The system, as indicated generally in Figure 14 at 301, comprises an insertable subassembly made up generally of an insert body 302, an insert base 303, and an elastomeric diaphragm 304.

Body 302 generally consists of a lower stepped skirt section 305 defining a stepped bore opening 309 in which is snugly fitted the insert base, and a top plate 306 closing off a large portion of the bore opening except for the capsule insert opening 307. A conicalwall transition zone 308 extends from stepped bore 309 to capsule opening 307 and further serves as a tapered seat for the elastomeric diaphragm 304 which is shaped much like a Belleville washer, with a tapered conical wall 320 and a flat annular flange 321. Diaphragm 304 is preferably formed of a flexible elastomer such as silicon rubber or vinyl acetate.

A series of eight radial air passages 310 pass through top plate 306, from a point near capsule opening 307 to a series of vertical slots 311 formed in a peripheral shoulder 312 formed around top plate 306.

Insert base 303 comprises a stepped cylindrical member having a wide bottom section 313 and a narrower top section 314. A large bore opening 315 is formed in section 313 and communicates with a small bore opening 316 in section 314. A generally hemispherical cup 317 is formed at the top of bore 316 in top section 314 and has a pair of diametrically opposed bleedby slots 318 and 31 9 cut therein to provide vacuum/pressure bypass from bore 316 around cup 317.

As previously described, the stepped cylindrical configuration of base 303 is sized for relatively snug-fitting engagement in the stepped skirt section 305 of the insert body.

Further sealing therebetween can be accomplished by the use of elastomeric seal members (not shown) such as O-ring seals located between the members, as is known in the art of sealing.

Attachment of base 303 to body 302 can be achieved by internal threading of the lower cylindrical portion of skirt 305 and matching external threads formed on the lower base cylindrical section 313. A series of four wrench engagement slots 322 are formed in the bottom of base 303 (Fig. 13)to allow tightening and loosening of the threadedly engaged sections.

The capsule gripping system is assembled by first inserting diaphragm 304 into insert body 302 such that the conical section of the diaphragm matches the conical section of the insert body. Base section 303 is then inserted into body 302 by rotation thereof to engage the two threaded cylindrical sections of the two elements. As insert base 303 is threaded into body 302, the upper surface of the base will contact the annular flange portion 321 of elastomei iz diaphragm 304 thereby securing this portion of the diaphragm in the assembly by class ping it between the base and the body.

In its relaxed position, diaphragm section 320 is maintained in its outer, open orientation by abutment with a conical abutment shoulder 323 formed on top of the insert base around cup 317. Assembled gripping systems 301 are then inserted in complementary recesses formed in weld wheel 203 and held by conventional means such as setscrews, snap rings, threads, etc.

OPERATION OF THE GRIPPING ASSEMBLY Operation of the gripping system occurs with the use of predetermined pulses of air pressure alternated with a source of vacuum.

In a typical sequence, an assembled telescoped capsule is dropped from one of the feedtubes 211 into the gripping system 301 whereupon the lower rounded end of the capsule seats in cup 317. As wheel 203 rotates, a vacuum source is sequenced and a vacuum is applied to bores 315 and 316.

This communicates via slots 318 and 319 to the underside of the tapered elastomeric sleeve section 320, pulling this downward until it frictionally grips the capsule and aligns it vertically in place. Simultaneously, a source of pressurized air may be supplied via air passages 310 to the middle section of the capsule to increase the pressure differential across the flexible diaphragm and also prevent a vacuum lock occurring in this area upon detelescoping of the capsule halves. It is also felt that the pressurized air helps detelescoping of the capsule halves by offsetting a possible vacuum which otherwise would be created inside the capsule as the halves are slid apart, mainly by slight infiltration of air between the capsules to prevent such a vacuum.

When the vacuum in hores 315 and 316 has pulled diaphragm 304 tightly down on the capsule, thus simultaneously aligning and clamping it, the upper rotatable weld mandrel 219, which is adapted for slight interference fit over the top half of the capsule, is brought down by the camming action of cam slot 221 and rollers 220 until it tightly engages over the capsule. This provides a good, tight frictional engagement of the mandrel on the capsule because diaphragm 304 maintains the capsule in proper vertical position to receive the weld mandrel 219. Engagement of the capsule in mandrel 219 is also augmented by a second vacuum source supplied to the inner bore of the mandrel via the upper rotary structure 218.

As the rotating elements continue around their cyclic sequence, vacuum is maintained on the upper and lower capsule gripping means and the capsule is detelescoped approximately 60 percent of its engagement distance to allow impingement of the steam jet as described elsewhere herein. Then continued sequencing brings the capsule halves back to their original full telescoping engagement simultaneously with the upper weld mandrel reaching the desired rate of spin. The gripping action of diaphragm 304 on the lower half of the capsule maintains it in a stationary mode as the upper half is rotated and retelescoped.

After the spin weld is performed on the retelescoped capsule, the air pressure and vacuum sources are reversed in order to relax the gripping of diaphragm 304 and simultaneously eject the welded capsule from the upper mandrel as it is moved upward by cam slot 221. The capsule is then easily ejected from cup 317 by upward moving air pressure through bores 315 and 316.

OPERATION OF THE SPIN WELDER In typical operation, the upper rotary joint, which as previously mentioned features sixty welding stations, is driven in a clockwise direction on a continuous motion basis. As the system rotates, prefilled capsules are supplied via chute 207 to orientation trough 208 whereupon the capsules roll into a longitudinal orientation in channels 255. The capsules are then swept by padded buffer wheel 209 into the parallel grooves of sheaves 211 which further orients the capsules in a proper vertical orientation with the large end up and the small end down. The capsules then travel in this orientation across the top of orienter 210 and drop into the six feed tubes 211. The feed tubes supply the properly oriented capsules into six adjacent positions on rotating weld wheel 203 which is also constantly rotating at the same speed as the upper rotary assembly.Thus lower rotary weld wheel 203 is likewise moving in a clockwise direction when viewed from above. The capsules which are then gripped in capsule recesses 279 formed in weld wheel 203 travel with the weld wheel around the circumference to a point near the bottom of Figure 6. Referring to Figure 5, it can be seen that cam slot 221 moves from an uppermost point near the center thereof. In effect this serves to lower the weld mandrels 219 which are traveling in cam slot 221. Thus as the capsules and weld mandrels approach this lowermost point of Figure 6, mandrels 219 move down over and into engagement on the tops of the capsules in weld wheel 203. As the weld mandrels 219 are lowered down onto the tops of the capsules by means of engagement in cam slot 221, vacuum is simultaneously applied to the weld head 223 to grasp the top half 102 of capsule 101.At this point, roller 220 has reached the lowermost travel point 280 of cam wheel 222. A short time thereafter, covering approximately 10 to 15 degrees of arc on wheel 222, the cam slot 221 rises a distance equivalent to the displacement "Z" illustrated in Figures 3 and 4 and shown in Figure 5 at 281. This serves to displace capsule top 102 upward an amount "Z" off of bottom 103. The weld mandrel then travels through slot portion 281 with the capsule thus displaced, around the lower left quarter of wheel 203 as illustrated in Figure 6. During this portion of travel, the weld mandrels engage spinner drive belt 245 which is continuously moving under the force of driving wheel 243. The speed of rotation is in the range of 100 to 300 rpm and the mandrels 223 are rotated on spindles 219 and obtain this speed fairly rapidly.As the capsules progress around the arc by movement of wheel 203, they come Into the vicinity of process generator 260 which emits a jet of steam approximately 1 to 3 thousandths of an inch in diameter which impinges the lower capsule in the region "Z" as indicated in Figure 3.

Since capsule 101 is being rotated at the aforementioned spinner speed of 100 to 300 rpm, the steam jet will Impinge the periphery of capsule bottom 102 several revolutions in the zone "Z". This will tackify the gelatin in this region.

As the capsules wove past the process generator in response to wheel movement 203, the cam slot 221 will move once again from the intermediate level 281 back to the lower level 280 as the capsules are spinning.

This moves the top section back down over the bottom section in each capsule until it is returned to the orientation illustrated in Figure 4. Because of the steam impingement on the lower section of the gelatin capsule and the resulting tackification of the gelatin, the spinning of the top onto the tackified surface results in a smooth, even fusion of the two gelatin capsule portions.

The spinning is then stopped and the capsules progress around the cycle until they engage discharge wheel 204 and are gripped by suction in one of the indentations 251 therein. This wheel is moving in a counterclockwise direction and preferably moves the capsules past an inspection station 226 which may comprise one or more of several different types of inspections, including, but not limited to, visual inspection, infrared inspection, x-ray inspection, sonic inspection, or any other of the known types to determine the integrity of the fusion bond between the two capsule portions. After inspection, the capsules reach the discharge area 227 whereupon vacuum in wheel 204 rapidly converts to air pressure and the capsule is ejected into a conventional conveyor system which then moves the capsule into the packaging and/or bottling area of the manufacturing plant.

Thus in summary, the capsules are fed through the following process steps: A. Feed and orientation; B. Location into the weld wheel; C. Partial separation of the capsule components; D. Spinning of the upper portion of the capsule on the lower portion; E. Tackification of the lower portion by impingement of a steam jet; F. Rejoining of the capsule sections during spinning operation; G. Take-up of the capsule in the discharge wheel; H. Inspection of the fusion bond in the capsule; I.Discharge of the capsule into the normal bottling operation; It is felt that the combination of the tackifying process utilizing the thin stream, low pressure steam jet, plus the spinning action of the weld mandrel serves to both create a good fusion medium plus also serves to homogenize and spread the tacky substance into a homogeneous consistent bond between the upper and lower capsule components. It should also be noted that the precise yet high speed operation of the present system prevents any contamination of the capsules while also allowing a very rapid, economical fusion process to be accomplished. The lack of contamination is achieved by maintaining the capsules in an engaged position at all times during the operation and never permitting any contact of the capsule contents with the outside atmosphere, or with any part of the welding apparatus.Such precise control is obtained by the exact and precise machining of cam slot 221 in the cam wheel and by the lack of any appreciable tolerances or play in all of the rotating elements of the present system. Thus with the present system, it is contemplated that approximately 1 20,000 capsules per hour can easily be fused in this system with just a minimum amount of energy expenditure.

ALTERNATE EMBODIMENTS Alternate embodiments of this invention are illustrated in Figures 15-21 in which the steam jet generator 260 of the previous embodiment is replaced by a fusion generator 560 located radially outward from weld mandrels 223. The fusion generator 560 is more clearly illustrated in Figures 15 and 16 and comprises a radiation source 561 held in a housing 562 mounted on a bracket 565. A pair of power leads 563 extend outwardly from housing 562 and are connectable to an available 220 volt or 440 volt power system.

The fusion energy source 561 preferably comprises either an ultrasonic generator, an infrared generator or a laser beam generator. In one particular preferred embodiment an infrared lamp was utilized as the fusion source 561 and connected by power leads 563 to an electric power supply.

In a second preferred embodiment an ultrasonic generator 561 for generating ultra sonic energy was placed in housing 562 and connected via leads 563 to an appropriate power source.

A thir#d embodiment of the fusion heat generator utilizes a laser beam generator in housing 562 for generating a shallow laser beam for impinging the gelatin capsules. In these three embodiments the fusion generator 561 mounted in housing 562 and held by bracket 565 is placed in close proximity to the exposed portion of the gelatin capsule denoted at "Z" in Figure 18. The upper portion of the capsule is held in mandrel 223 for providing a spinning of the top portion of the capsule. The bottom portion of the capsule is held in a gripping member located in weld wheel 203. The power source connected to the fusion generator 561 may be either intermittent and controlled by mechanical or electrical switching means located on the rotating wheel 203, or may be of a constant source requiring no switching system dependent upon rotation of wheel 203.

In typical operation the power supplied via leads 563 is converted into a source of energy which can impinge area "Z" of the lower capsule half and provide sufficient energy to soften the surface of the lower capsule.

Whether the energy is provided in the form of infrared heat, ultrasonic waves, or laser beam, the power has been preadjusted to provide just enough energy to soften the external surface of the capsule structure. After the weld wheel has rotated the capsule out of range of the fusion generator 560, spinner mandrel 223 is activated and simultaneously, cam slot 221 serves to reengage the capsule halves thereby contacting the spinning top capsule half with the softened area "Z" of the lower half and providing a fusion of the two capsule halves.

In another embodiment of the invention illustrated in Figure 17, a source of fluid 360 is provided utilizing either vacuum or pressure atomization to emit an atomized spray of fluid from atomizing spray nozzle 361. A mechanical cam lobe 362 preferably is attached to the lower end of wheel 203 to engage a trip lever 363 projecting downwardly from the bottom section of solution generator 360. In one embodiment, a tank of solvent such as water, which is a preferable solvent for a gelatin capsule, is pressurized and supplied to an atomizing spray nozzle 361. Thus when wheel 203 rotates sufficiently, cam 362 engages trip lever 363 thereby opening the pressurized fluid to the spray nozzle 361 whereupon it is atomized into a very small droplet spray and impinges the disengaged section "Z" of the lower capsule half.In an alternate embodiment, rather than utilizing a pure solvent such as water for the gelatin capsule, a solution mix was provided containing gelatin dissolved in sterilized water to provide further tackification of the lower capsule half. Nozzle 361 and generator 360 can be of any commerically available atomization system such as, for example, the paint-sprayer type atomizer utilized in commerical painting operations. Likewise, whereas the camming and tripping mechanism 362, 363 is illustrated, an alternate embodiment would be to utilize a constantly emitted spray for impinging the capsules. It should be noted that a camming member 362 may be located at each capsule location on wheel 203 in order to provide a spray cycle for each capsule.It should also be noted that a sensing means (not shown) can be associated with each capsule recess in 203 to sense the presence or absence of a capsule therein and the said sensing means can be operably connected to cam member 362 in order to retract the member when a capsule is absent. This would prevent the emission of an impingment spray in the invent a vacant capsule recess passes the spray nozzle 361.

Figures 20 and 21 illustrate yet another embodiment of the capsule welding process wherein the fusion generator 460 comprises a heated contact wire for applying heat directly to the fusion area of the capsule. Either induction heating or direct resistance heating may be utilized in the contact wire. Preferably the wire is coated with a nonstick material such as polytetraflouroethylene (PTFE) also commonly known as Teflon (R.T.M.). In Figure 20 the fusion generator 460 comprises a main bracket 461 having electrical insulators 462 and 463 mounted thereon upon which is mounted a heated wire 464. A pair of electrical leads 465 and 466 are operably connected to heating wire 464 through the center of insulators 462. The heating wire 464 extends above wheel 203 into direct tangential contact with capsules located in recesses of wheel 203.

Figure 21 is a side schematic view of heating wire 464 shown contacting engagement area ''Z'' of a disengaged capsule assembly. In operation one or more of the heating wires 464 may be located in a tangential orientation with respect to one or more of the capsule positions in wheel 203. As the wheel rotates continuously the capsule sections are brought into contact with heating wire 464. Although not shown in Figure 21 it is preferable that a rotating system be utilized in the lower section of capsule in order to rotate the capsule against the heating wire and obtain a 360 tackified surface. Also, although not shown, in the drawings it is clear that a pair of parallel heating wires could be utilized merely by placing them in parallel location on insulators 462.

Thus, in typical operation the embodiment of Figures 20 and 21 would operate similar to that of previous embodiments, i.e. as wheel 203 rotates it brings capsules located therein into tangential contact with the heating wire 464, and as the capsule contacts the heating wire it may be rotated rapidly to provide a 360" contact surface with the heating wire, or any portion thereof sufficient to secure the capsule halves together. After the capsule half has passed out of contact with the heating wire, the upper capsule section is reengaged over the engagement section "Z" and either the top, bottom, or both halves may be rotated to homogenize the tackified surface therebetween.

In addition to the tackification systems described hereinabove relating to heating and solution spraying additional means of fusing the capsules together utilize increased frictional surface treatment between the capsule halves. Figures 18 and 19 illustrate two embodiments of this concept. In Figure 18 the lower capsule half 103 has been abraded in a cross-hatch pattern in the area of engagement zone "Z" to provide a roughened surface for enhanced frictional engagement in the upper capsule half 102. In one preferred embodiment capsule halves 103 are abraded prior to their entry into the filling system.In a separate embodiment (not shown) a simple abrasion system may be incorporated on wheel 203 and tied into the rotational system connected with mandrel 21 9 and/or a rotational system located in wheel 203 to provide an abrasion of capsule half 103 immediately prior to spinning engagement in capsule 102.

In either instance the increased frictional resistance between upper and lower capsule halves arising from the enhanced frictional surface "Z" provides sufficient heat to fuse the gelatin sections together upon merely the spinning action of mandrel 219.

Figure 19 illustrates an alternate embodiment for enhancing the frictional resistance between the capsule halves and comprises a lower capsule section 103 having raised frictional ridges 103A molded in place on the exterior surface thereof in the engagement zone "Z". These ridges may be purely vertical, purely horizontal, or any combination of horizontal and vertical such as checkerboard or helical. The engagement of upper half of the capsule 102 over the lower capsule half 103 causes a very tight engagement with ridges 103A such that spinning of capsule half 102 provides a rapid buildup of heat in the ridge areas 103A thereby tackifying these areas and providing a ridge- or spot-type weld of the lower capsule half in the upper capsule half.

OPERATION Operation of the alternate embodiments is identical to that of the previous embodiments shown in Figures 1-14, as far as moving the capsule halves into position for fusion and for spinning the capsule halves together and rejecting them from the welder.

Although a specific preferred embodiment of the present invention has been described in the detailed description above, the description is not intended to limit the invention to the particular forms or embodiments disclosed therein since they are to be recognized as illustrative rather than restrictive and it will be obvious to those skilled in the art that the invention is not so limited. For example, whereas one particular type of feed system and orienter is disclosed it is obvious that other types of feed conveyors and orienters could be utilized using systems such as air, vacuum, sensing wires, and other such apparatus. Also whereas the present invention is shown as operating at the end of a capsule filling line this system could be integrated into the capsule filling line.

It should also be noted that whereas the present invention has been disclosed with reference to rigid gelatin capsules, a more generic definition of rigid gelatin is that it is a thermoplastic material and the methods and apparatus of the present invention can be easily adapted to the fusion of telescopic capsules formed of other types of thermoplastic materials. For example, these methods and apparatus can be utilized to fuse thermoplastic polymers rather than rigid gelatin capsules. It should also be noted that other means for tackifying the telescopic area between the capsule halves can be utilized other than the steam generator means shown herein. For example, one could utilize a spray of a solvent for the thermoplastic material to tackify the telescopic areas.For example, when fusing capsule halves of a thermoplastic polymer a hydrocarbon solvent for the polymer could be utilized. Also in the fusion of gelatin capsules a solvent comprising a solution of the gelatin in water or other gelatin solvent can be used as the tackifying agent. In such an instance the steam generator illustrated herein can be replaced with a solvent emittor utilizing either high pressure or vacuum emission principles.

It is forseen that the gelatin utilized in the capsules can also be utilized in the solvent emittor by disolving such gelatin in any of its available solvents. In one embodiment it is foreseen that the gelatin can be dissolved in a sterilized water to form the tackifying surface between the capsule halves. Sterilized water is preferred to maintain the integrity of any consumer product located inside the the capsule.

Other means for tackifying the telescopic area between the capsule halves include placing heating means in close proximity to each of the capsule halves and heating the local peripheral area therebetween. Such heating means include electrical resistance heaters, radiant heaters, laser heaters, conductance heaters, plasma jets, ultrasonic generators, radio-frequency heaters, microwave generators, and flame heaters. Other equivalent heating means known to those skilled in the art likewise could be substituted for the tackifying means disclosed hereinabove.

Additional means of homogenizing the tackified surfaces between the capsule halves in clues, sun addition to the aforementioned rotational homogenizing step, the step of homogenizing by axial oscillation of the capsule halves together in their telescopic state. Oscillations in the range of from about 20 to about 20,000 cycles per second can be utilized for said homogenizing step. This compares favorably to the aforementioned rotational homogenizing which preferably occurs at a rate of from about 20 revolutions per minute to about 2,000 revolutions per minute. Thus the invention is declared to cover all changes and modifications of the specific example of the invention herein disclosed for purposes of illustration, which do not constitute departures from the spirit and scope of the invention.

Claims

1. Process for forming tamper resistant or tamper-indicative capsules comprising two telescopable capsule halves made of rigid gelatin or any other thermoplastic material, the bottom half being filled with the consumable product and the upper half being in close fitting telescopic engagement over said bottom capsule, said process comprising exposing portion of an engagement zone in the telescopic region between said capsule halves; tackifying the gelatin in at least a portion of said exposed zone; spinning at least one of said capsule halves in relation to the other said half; and, combining said capsule halves in fully telescoped engagement during spinning thereof.

2. Process according to claim 1 comprising: locating a capsule vertically in an opening in a rigid housing assembly, said housing assembly having a flexible, pressure-responsive circular diaphragm therein; applying a pressure differential to said diaphragm in a direction to flex said diaphragm inward against said capsule in said housing; and, relaxing said pressure differential after spin welding of said capsule has been performed.

3. Process according to claims 1 and 2, further comprising the additional step of ejecting said capsule from said housing by reversing the direction of said pressure differential, thereby relaxing said diaphragm and blowing said capsule out of said housing assembly.

4. Process according to anyone of the claims 1-3 wherein said pressure differential applying step comprises applying a vacuum to the bottom of said capsule and simultaneously to the bottom of said diaphragm.

5. Process according to any of the claims 14 wherein said applying step also comprises the step of appyling air pressure to the middle of said capsule and the top of said diaphragm.

6. The process according to claim 1 wherein said tackifying step further comprises applying heat by external energy applying means.

7. The process according to claim 1 comprising: forming on at least a portion of the telescopic engagement surface of at least one of said halves an enhanced friction surface; said forming step comprising abrading said surface to form a rough surface or molding at least one discreet, raised friction point on said surface during the manufacture of said capsules.

8. Process according to claim 1 comprising: exposing a portion of the telescopic engagement zone between said capsules; spraying a non-steam tackifying liquid on said exposed zone portion; and, telescoping together said capsule halves while spinning at least one of said halves to thereby homogenously fuse said halves together.

9. The process according to claim 8 wherein said tackifying liquid comprises water, gelatin dissolved in water or steam.

10. Apparatus for forming tamper resistant or tamperindicative capsules comprising two telescopable capsule halves made of rigid gelatin or any other thermoplastic material, the bottom half being filled with the consumable product and the upper half being in close fitting telescopic engagement over said bottom capsule, said apparatus comprising: an orienter for placing telescopically joined capsules in a predetermined, desirable vertical orientation; upper and lower gripping means for gripping top and bottom capsule halves, respectively; means for partially detelescoping said capsule halves; tackifying means for tackifying a segment of the telescopic surface of at least one of said capsule halves; means for rotating said tackified capsule half with respect to said other capsule half; and, additional means for retelescoping said capsule halves together simultaneously with said rotating means.

11. The apparatus according to claim 10, comprising a plurality of upper and lower grips in vertically opposed relationship.

1 2. Apparatus according to claim 10, comprising a gripping and alignment assembly including an insert body having a central bore opening, on insert base insertable in said bore opening, and a flexible gripping diaphragm clamped between said body and said base and having a wall section adapted to move from a relaxed, non-gripping position to a gripping position on a capsule in said body, in response to a pressure differential across said diaphragm.

13. Apparatus according to claim 12 wherein said diaphragm comprises an elastomeric conical wall section having a bore opening sized to fit loosely around a gelatin capsule in a relaxed state, and adapted to grip a capsule tightly in response to a pressure differential in only one predetermined direction across said conical wall section.

14. Apparatus according to claim 12, wherein said insert base comprises a member having a central bore opening communicating with a hemispherical cup having at least one pressure bypass slot formed therein.

15. Apparatus according to claim 12, comprising a rigid housing means having a generally centrally located capsule receptacle with a cupped bottom; a flexible elastomeric gripping diaphragm in said housing means above said cupped bottom and having a central capsule opening therethrough; said diaphragm arranged to be flexed into gripping engagement against a capsule located in said capsule opening, in response to a pressure differential thereacross; and, pressure differential passage means in said housing means communicating with said diaphragm.

16. Apparatus according to claim 15, wherein said passage means comprises an air passage communicating with said cupped bottom, and at least one pressure bypass slot around said cupped bottom.

17. Apparatus according to claim 15, wherein said housing means comprises a skirted, hollow insert body having a central capsule opening therein, and an insert base having a central cup with a bore passage communicating therewith; said insert base being snugly engaged in said skirted body.

18. Apparatus according to claim 15, wherein said diaphragm comprises a tapered conical section of a flexible elastomer attached to a flat annular flange portion; and said diaphragm is secured in said housing assembly by clamping of said flange portion between said insert body and said insert base.

19. Apparatus according to claim 15, wherein aid tackifying means comprises a jetspray emittor for emitting a spray of tackifying agent against said capsule half, said jet spray emittor being for example a steam jet generator.

20. Apparatus according to claim 10 wherein said limiter comprises at least one cam shoulder, and at least one cam follower engaged in said shoulder and operatively connected to one of said grips.

21. Apparatus according to claim 10 wherein said gripping means and said rotating means comprises an upper rotatable capsule wheel, a lower rotatable capsule wheel, and at least one spinnable mandrel rotatably mounted in one of said rotatable capsule wheels; with rotation power means operable on and selectively connectable to said spinnable mandrel.

22. Apparatus according to claim 10 wherein at least one of said capsule wheels is vertically reciprocable and is operably connected to and reciprocated by said cam shoulder means.

23. Apparatus according to any of the claims 7 to 22 wherein said lower grips are mounted on a rotatable platform and said upper grips are mounted on vertically reciprocable and spinnable mandrels connected to said cam follower.

24. Apparatus according to claim 19, said steam generator system for creating a steam impingement jet, comprising: a hollow, enclosed generator housing having a fluid inlet connection and a steam outlet connection; an electrical heating element in said housing having electrical contacts extending sealingly through said housing wall; impingement baffle means in said housing to strip excess moisture from generated steam; high level and low level water probes; and, a temperature probe in the steam flow area in said housing, having a signal lead extending through the wall of said housing.

25. Apparatus according to claim 24 further comprising pressure relief means and manual drain means in the wall of said housing.

26. Apparatus according to anyone of the claims 24 or 25 comprising a hollow enclosed housing having a fluid inlet connection and a steam outlet connection; an electrical heating element in said housing having electrical contacts extending out of said housing; a highliquid-level probe in the upper portion of said housing having a signal lead extending out of said housing; a low-liquid-level probe in the lower portion of said housing having a signal lead extending out of said housing; a temperature probe in said housing having a signal lead extending out of said housing; a sterile water storage tank having inlet and outlet water connections and a condensation coil therein; a low water logic probe extending into said tank and having a signal lead extending there out of; pumping means connected to said outlet water connection and having a command lead adapted to turn said pump on and off; a power controller connected to said electrical contacts and adapted to provide varying power to said heating element; a temperature controller connected to said temperature probe and said power controller and adapted to receive a temperature signal from said probe and control said heating element via said power controller to maintain a predetermined desirable temperature in said generator; and, a process controller connected to said low water logic probe signal lead, said pumping means command, said high-liquid-level probe lead, and said lowliquid-level probe lead, and adapted to maintain a predetermined liquid level in said generator and further adapted to generate a system shutdown signal upon reading a low water level signal in said tank.

27. A tamper-resistant, tamper-indicative capsule obtained in carrying out the process according to anyone of the claims 1 to 9.