EA003124B1 - Method and apparatus for sealing capsules suitable for use in said method and apparatus - Google Patents

Abstract

1. A method of sealing a hardshell capsule having coaxial body parts which overlap when telescopically joined with each other, thereby forming a gap around a circumference of the capsule, comprising the steps of: individually applying a sealing liquid including a solvent uniformly to the external edge of the gap of a capsule to be sealed to form a liquid ring around the circumference of the capsule, removing excess sealing liquid from the exterior of the capsule, drying the capsule by applying thermal energy from outside while gently tumbling and conveying the capsule on a spiral path. 2. The method of claim 1, wherein the excess sealing liquid is removed by a combination of air jets and aspiration. 3. The method of claim 1 or 2, wherein the flow velocity during application of the sealing liquid is controlled such that the liquid ring is formed which expands to just touch the capsule. 4. An apparatus for sealing a hardshell capsule having coaxial body parts which overlap when telescopically joined with each other, thereby forming a gap around a circumference of the capsule, comprising: means for individually applying a sealing liquid including a solvent uniformly to the external edge of the gap of a capsule to be sealed to form a liquid ring around the circumference of the capsule, means for removing excess sealing liquid from the exterior of the capsule, means for drying the capsule by applying thermal energy from outside while gently tumbling and conveying the capsule on a spiral path. 5. The apparatus of claim 4, wherein said means for individually applying a sealing liquid comprise a plurality of spray nozzles uniformly spaced around the circumference of the capsule and directed at the external opening of the overlap gap and means for controlling the temperature of the sealing liquid, of the capsule and of the atmosphere at the gap. 6. The apparatus of claim 4 or 5, wherein said means for drying the capsule comprises a rotatable cylindrical drying basket device with an internal vane arrangement extending along the axis of the cylinder and arranged such that the capsule tumble and are conveyed on a spiral path upon rotation of the drying basket device. 7. The apparatus of claim 6, wherein said cylindrical drying basket device is surrounded by a solid walled container with air vents and means are provided to feed conditioned air at large volumes at high velocity into the drying basket device. 8. The apparatus of claim 6 or 7, wherein said drying basket device has a rectangular cross section and flat angled baffles as the internal vane arrangement. 9. A capsule having hardshell coaxial body parts which overlap when telescopically joined with each other to be sealed with the action of a solvent applied to the overlapping region, wherein spacing features are provided so as to provide a uniform gap in the overlapping region, said spacing features being structured such that they soften with the action of the solvent so that the gap is thereby closed. 10. The capsule of claim 9, wherein a seal is provided at the end of the gap exposed to the interior region of the capsule to prevent a product filled into the interior region from flowing into said gap. 11. The capsule of claim 9 or 10, wherein a product filled into the interior region is immobilized to prevent it flowing into said gap.

Description

The present invention relates to a method and apparatus suitable for sealing telescopically connecting capsules with coaxial, partially overlapping parts of the body by successively leading the solvent and thermal energy. In addition, the present invention relates to a capsule design, particularly suitable for use in such a process and apparatus.

Capsules to be sealed with the present invention are preferably solid shell gelatin capsules or other capsules made from materials or their compositions that have pharmaceutically acceptable chemical and physical properties.

The problem that must be solved in relation to such capsules in comparison with other dosage forms is that the coaxial parts of the body must be well sealed to avoid leakage of the capsules out or contamination. Secondly, for security reasons, damage to the contents of a capsule or capsule itself must be obvious and visible from the outside, and any capsule sealing technology must be suitable for producing large quantities in order to reduce production time and cost, as well as reduce the waste arising from - due to product defects.

EP 0 116 743 A1 and EP 0 116 744 A1 patents disclose, respectively, similar methods and devices for sealing such capsules having solid-wood coaxial roof and body parts that overlap during telescopic connection. The process used includes the stage of immersing batches of randomly oriented capsules in mesh baskets, or capsules oriented with their lid part upwards, into a sealing liquid, applying a capillary effect in the area of overlapping of the lid and housing parts or spraying the sealing liquid or driving it away with steam to the overlap seam, removing sealing fluid from the surface of the capsules using an air compressor, and supplying thermal energy to the capsules during transport of the baskets through the drying chamber . Both documents disclose the use of a variety of sealing liquids, as well as specific temperatures and methods for supplying thermal energy, the disclosure of which is included in the present description by reference.

EP-0 180 543 A1 also discloses a method for sealing telescopically connected capsules with coaxial housing parts by sequentially supplying sealing liquid to an overlapping area at the junction between the cover and the housing, removing excess sealing liquid and supplying thermal energy for drying. This document describes, in particular, various designs of capsules suitable for use in such processing, which have a special structure with guides on the lid and / or on the body for precise coaxial positioning of the lid and body relative to each other. The disclosure of this document is also included in the present description by reference.

Previous systems sealing telescopically connected capsules with coaxial parts of the body by sequential supply of solvent and thermal energy are partly imperfect in terms of quality of the junction and controllability of process parameters that affect the quality of the junction.

The present invention aims to create an improved method and apparatus for sealing telescopically connected capsules with coaxial partially overlapping parts of the body by sequential supply of solvent and thermal energy, as well as an improved capsule design suitable for use in such a method and apparatus.

In accordance with this task, the present invention provides a method and apparatus for sealing telescopically connected capsules with coaxial partially overlapping parts of the body and a capsule design as defined in the appended claims.

Hereinafter, the present invention will be described in detail, by examples, with reference to the accompanying description of the drawings, where FIG. 1 shows, on an enlarged scale, the details of the device of the overlapping sealing part of the capsule according to the present invention; and FIG. 2 shows schematically the structure of the drying basket used in the method and apparatus according to the present invention, as well as part of the capsules during their processing.

First, a general description will be made of a system including a method, an apparatus and capsules according to the present invention in order to highlight its main features and aspects. The list below is not arranged in any order and is not exhaustive, but only briefly covers the advantages that distinguish this system from previous methods.

The present invention provides the following advantages.

There is no need for oriented capsules, which simplifies working with them and increases the reliability of the process.

The supply of sealing fluid is spatially adjustable in order to optimize the position of wetted areas to ensure good sealing with minimum thickness and with the fastest possible drying.

The temperature of the sealing fluid can be adjusted to achieve effective suction and optimal dissolution rate. This means using both heating and cooling systems, since, for example, systems using gelatin capsules require temperatures above room temperature, while systems based on HPMC (hydroxypropylmethylcellulose) work best with hot solvents and when drying is carried out at room temperature. temperature

The volume of sealing fluid introduced into the space around the gap between the capsule body parts, i.e. the lid and the body, is adjusted to avoid excessive wetting.

The sealing fluid is applied uniformly around the capsule in order to achieve the required complete sealing.

Excess sealing fluid is removed using a combined exposure to air jets and / or air suction.

The system is designed in such a way that changing the size of the capsules requires a minimal change in the components.

The system is designed to work with a variety of sealing liquids, including but not limited to such liquids as an alcohol-water mixture in the case of gelatin capsules, as described in EP 0 116 743 A1 and EP 0 116 744 A1, incorporated by reference. For capsules made from other materials, such as starch, HPMC, etc., alternative solvent systems are required. In order for the processes used to be optimized and well managed, the present invention provides wide possibilities for controlling parameters that are critical for sealing and drying processes, such as temperature, solvent composition, time, air flow.

Transporting the capsules after sealing is achieved in a way that minimizes the contact of the capsules with the surfaces of the device and with each other, in order to reduce the risk of sticking or causing cosmetic damage.

The drying speed of the capsules is carefully controlled to ensure that the internal overlapping surfaces are reliably connected to each other as the solvent evaporates, but at the same time the liquid does not have enough time to diffuse into the volume of the capsule material.

Reliable attachment of the cap to the body requires that the overlapping surfaces be in contact in a position in which the surface will be welded into the seam, and with a force comparable to the minimum time required for the long-chain gelatin molecules to intertwine with each other. This determines the drying rate at which the system must be configured.

The contact pressure between the surfaces to be joined is maintained by a combination of interfering forces due to precise production control of the capsules and expansion of the gelatin due to fluid absorption.

Drying of all surfaces at a constant speed is necessary in order to avoid distortion or poor sealing, and is achieved by the capsules tipping mechanism when blowing air in the drying basket of the present invention.

When carrying out the drying process, an air flow is used with controlled temperature, speed and humidity, chosen in such a way as to achieve the temperature, time, humidity profile necessary to achieve a strong connection of the capsules.

The capsules are dried in a drying basket, which provides control of the transport speed, while at the same time exposing the capsules to a gentle tilting to ensure uniform drying of all surfaces and to prevent the capsules from sticking to each other.

The surface, material and shape of the screw in the drying basket are designed to ensure that the capsules are not kept and are minimally damaged when in contact with it during processing.

The porosity of the structure forming the drying basket is designed in such a way as to ensure low air resistance and a uniform flow of air to the capsules.

Two or more parallel strong air jets, adjustable in width and position, are directed upwards along a line from the lowest point of the drying basket at a speed sufficient to lift all capsules that tend to stick to the surface.

The speed control of the drying basket allows control of the drying time, since the speed of axial transmission is a function of the speed of rotation.

Controlling the parameters of the drying air is achieved using control servo systems that maintain uniform conditions even in the case of external changes.

The complete sealing system is designed as an autonomous unit with a small service area, which makes it possible to install it directly near the capsule filling lines.

Thus, the system according to the present invention makes it possible to seal capsules filled with liquid immediately after filling at rates compatible with conventional capsule filling lines.

Since the apparatus according to the present invention can be refueled from a standard accumulator, there is no requirement for a tight connection between the filler outlet and the inlet of the sealing apparatus according to the present invention. This allows the use of buffer volumes to smooth the flow of products in the case of short stops filling or sealing apparatus.

The main improvement of the method and apparatus according to the present invention compared with previous generations of sealing systems is to regulate the geometry of the gap between the parts of the capsule body to ensure a completely uniform capillary flow of fluid along the entire overlap length, as well as a constructive solution to the drying process or appropriate devices for this which remove the solvent in such a way that it causes a complete overlap of the gap and excellent adhesion of the parts together enclosures.

Capsule design

Structurally, the capsule, most suitable for use in the sealing system according to the present invention, consists of two halves, which partially overlap in a concentric manner with their telescopic connection. The main way in which the seal between the two halves is performed is to introduce a solvent or sealing fluid into the gap between the two halves in the overlap area, so that as soon as the solvent evaporates, the inner surfaces are brought into contact while they are soft and fused with each other. a friend.

To achieve good sealing with this method, it is necessary that the sealing liquid, i.e. the solvent, fill the entire gap between the surfaces that must be connected together. For capsules, this is the total length of the overlapping area between the lid and the housing. The two surfaces that must be joined together must react with the solvent so that the inner surfaces are soft and adhere to each other, while they are brought together to form a joint. This can be achieved by controlling the temperature and time during which the solvent is in the gap before it evaporates, bringing the surfaces into contact. Finally, the solvent removal operation requires the application of force to the two surfaces to be joined in order to keep them together while the connection is formed.

In the present invention, the solution to these problems is based on the design of the capsule, the use of the solvent and the drying mechanism.

To ensure a uniform filling of the gap with a solvent, the capsule is designed in such a way that it has elements that evenly separate both surfaces from each other at a predetermined distance, while a solvent is introduced into the gap. If the gap is wide in some places and absent in others, then the distribution of the solvent over the area will change, which will lead to poor sealing at some points around the capsule. It is envisaged that the gap closes completely when the solvent is removed and a compound is formed. The forces causing the gap closure are limited in magnitude, so that any resistance to surfaces attracted to one another can reduce the strength of the joint. In addition, since the product inside the capsule is not a solvent for the capsule material and, if it penetrates the gap, it will block the action of the sealing solvent, the design of the capsule is preferably done in such a way as to prevent contamination of the gap by the products inside the capsule.

An important aspect of the invention is the accuracy with which all these requirements are met within the tolerances of the manufacturer of the capsules and during the regulation of parameters such as temperature, time, volumes of solvents, solvent localization, drying conditions in a sealing system.

Various capsule designs are available to achieve the required clearance control, while at the same time ensuring all other requirements for capsules, such as appearance, manufacturability, ease of ingestion, etc. A number of suitable structures have been incorporated by reference into the description of the invention EP 0 0 0 0 543 A1. In one preferred embodiment, a symmetrical arrangement of at least three growths in the housing is used, which can arbitrarily engage with recesses or a groove in the lid. These elements provide axial positioning and keep the cover in a concentric position relative to the body, thus ensuring a uniform clearance. A specific implementation of the invention may include one or more variants, such as the presence of axial raised rings and matching grooves, the presence of surfaces with uniform roughness on one or more sides, the presence of many growths and grooves, a set of grooves and grooves along a circular contour, and the presence of spiral grooves protrusions and recesses.

The size of the gap is chosen in such a way that the volume of the solvent flowing through the capillary mechanism is sufficient to fill the internal surfaces of the gap so as to modify them, making them soft and sticky, which allows them to join when pressed together. This volume will depend on the material, temperature and force applied to connect the surfaces. Typically, the size of the gap is in the range from 0.05 to 0.5 mm. The volume of solvent required for the initial filling of the gap, usually lies in the range from 5 to 20 μl.

In order to make it possible to close the gap after removing the solvent, one should take into account the movement performed. This can be achieved with the help of a number of constructive solutions, a common feature of which is that these structures lack elements protruding into the gap, which remain sufficiently rigid and prevent the closure of the gap. In the case of using special elements that provide a gap, it is especially advisable to construct such elements in such a way that, when softened as the solvent acts, the elements are distorted in such a way as to effect the desired movement. An example of such an element is shown in FIG. one.

The geometry of the clearance element shown in this drawing is such that there is an ambient space that allows the build-up material to flow inwards when the gap closes. Corresponding design solutions are possible for other implementations, provided that the principle is followed, according to which the deformation of shapes adapted to the minimum movement is allowed.

Protecting the product from entering the gap when there is a solvent, requires sealing at the end of the gap facing the inside of the capsule, providing positive pressure from the outside to the inside of the capsule to prevent the product from flowing into the gap, and / or immobilizing the product to prevent it from flowing into the narrow gap.

In a preferred embodiment of the capsule used in the method and apparatus according to the invention, sealing of the upper part of the gap is applied using appropriate design of the elements providing adhesion.

Solvent supply

The second requirement for the sealing process is to modify the internal surfaces of the gap between the lid and the body so that they become soft and sticky as they are drawn together. As previously described, this requires control over the type and amount of sealing fluid or solvent, as well as its temperature. The present invention provides a mechanism for implementing its concept using a wide range of solvents, the type of which is described in previous patent applications relevant to this field or included as references. The use of capsules having a well-adjustable gap, which is hermetically sealed from the contents of the capsules, facilitates the impregnation of the internal surfaces with the required volume of solvent.

In a preferred embodiment of the invention, the solvent is supplied to the outer edge of the gap in a uniform manner along the entire circular contour. The effects of surface tension drag the solvent from the outside evenly into the gap, provided that the gap is even. To prevent the softening of exterior surfaces, all excess solvent is removed as quickly as possible.

There are various methods for delivering the solvent into the gap, including spraying coming from several points around the capsule and directed to the outer edge of the gap and lasting for a period sufficient to deliver a corresponding volume of solvent to the capsule, or the above-described implementation of the invention, but in which the spraying is replaced by a piezo line - or thermal ink nozzles that distribute the appropriate solvent, or a system of sponges, brushes, wicks, etc., that transfer the solvent by contacting the required floor voltage and jets of solvent vapor directed to the open end of the gap to condense the vapor directly on the capsule.

In addition to distributing the required volume evenly around the entrance to the gap, the system must remove all excess liquid solvent from the surface of the capsule before it softens the material. This can be achieved in various ways, including suction of the liquid, use of air jets to blow liquid from the surface, capillary suction and absorption of liquid upon contact, use of a shake to throw away excess liquid, or a combination of these measures.

In a preferred embodiment of the sealing apparatus according to the present invention, three spray nozzles are used, separated from each other by an angle of 120 ° around the circumference and directed to the outer lumen of the gap formed at the overlap site, while the excess fluid is removed using a combination of air jets and suction. In addition to accurately controlling the volume of the solvent and the place to which it is delivered, it is necessary to maintain the temperature of the capsules, the solvent and the atmosphere within certain limits. The required level of regulation depends on the materials and the variability of environmental parameters. The device is provided with a temperature control system suitable for these purposes, providing appropriate conditions for functioning in a wide range of environmental parameters.

Solvent removal

The third requirement is to remove the solvent in the gap in such a way that it creates a force that holds the surfaces together during their drying. The final way to remove the solvent is to remove it in the form of vapor, while transporting it by way of entrapment into the air stream at the appropriate temperature. The solvent is transported from the gap to the air flow through several mechanisms, such as movement along the gap to provide evaporation from the exposed surface of the liquid, diffusion through the capsule cap material for evaporation from the outer surface, diffusion through the capsule body material and mixing with the liquid contained in the capsule or absorption by this fluid, as well as diffusion inwards and binding to the material of the cap and the capsule body.

All these methods can be applied in the drying process so that the solvent is removed without introducing air. When this happens, the atmospheric pressure squeezes the surfaces of the cover and body together under pressure up to 100,000 N / m ² .

All these transport mechanisms are accelerated with increasing temperature. However, excessive temperature can lead to situations that prevent a good connection to form, such as the formation of vapor bubbles and surface distortion, excessive fluid flow rates that allow air to be captured, an increase in internal pressure, displacing air from the inside of the capsule through the gap, thermal stresses that distort the capsule, or excessive drying of external surfaces, which increases rigidity and prevents closure of the gap.

The present invention optimizes the temperature and air flow to ensure drying of the capsules at an acceptable rate without deteriorating the quality of the sealing performed by any of the mechanisms described above.

The preferred implementation of an apparatus for sealing capsules will be described in detail below.

In one preferred embodiment, all requirements and all devices for efficient sealing are implemented in a stand-alone machine.

In this embodiment of the invention, there is an input feed hopper that can receive capsules from any source at any speed. Usually, capsules are served using a conveyor or air transport system.

At this stage, the capsules, with the help of elements on the lids and housings, are in a mechanically closed state in order to partially seal enough to prevent the contents of the capsules from leaking during the mechanical transport with the sealing system.

The loading hopper is designed to feed the capsules into a series of inlet tubes that will transport these capsules to a sealing apparatus. With the help of gravity, the capsules are fed from the hopper into the pipes, and this movement of the capsules is assisted by reciprocating movement of the pipes in the vertical direction in the range of 0.5 to 5 cm and at a speed that ensures smooth, non-stop movement.

A conventional capsule orientation device can be inserted between the feed hopper and the feed tubes, allowing the capsules to enter the tubes with a predetermined orientation. This function is not necessary for effective sealing, but can be used in combination with a head with a reduced spray area designed to minimize the amount of solvent used or to limit the softening of the outer surfaces of the capsules.

In one embodiment of the invention, six pipes are used, and this number will be taken as an example for the subsequent descriptions, however, implementation options with any number of parallel paths can be used to provide the required throughput.

Capsules in the inlet pipes are prevented from movement by means of mechanical valves, opening cycles of which are regulated by the system control device. To implement the sealing function, it is necessary to perform a large number of actions that are precisely synchronized in time and coordinated with each other. In a preferred embodiment of the invention, all these actions are controlled by a programmable logic control device (PBC), so that the sequence of actions and their synchronization in time can be adjusted to meet the requirements that a number of solvent systems fit capsules of various designs and made of different materials. A distinctive feature of the present invention is that the use of PbC allows using only one machine to work with different processes, materials and sizes of capsules.

Actions commanded by the control device can be carried out using a combination of a number of actuators, including such as (but not limited to) solenoids, pneumatic valves and cylinders, motors and cams.

At the beginning of the sealing cycle, PСC releases the valve that holds the capsules and allows the capsule in front of each tube to fall into the place where the sealing will be performed. This place is known as a spray boom. The spray boom has a mechanism that holds the capsule in place, while the solvent is sprayed onto the middle part of the capsule so that it evenly contacts circumferentially with the end of the overlapping area created by the overlay of the lid over the body. This is achieved by surrounding each capsule with a ring-shaped nozzle, in which there are a number of small holes. These openings are located and rotated so that the fluid flowing out of them reaches the capsules at the desired location. If the capsules are not oriented, then the surface on the capsule intersecting with the solvent must be such that, regardless of the orientation of the capsule, the edge of the gap is covered with solvent. If the capsules are oriented, the area covered by the solvent can be reduced just to the surface around the end of the gap. To achieve the desired covering power of the system, the holes are angled, usually at an angle of 45 °, and evenly distributed around the capsule.

Each spray boom has openings for each of the capsule supply tubes, usually six, and fluid is supplied to the spray nozzles through the nozzles in the spray boom. The fluid is forced from the nozzles to the capsules due to the pressure applied by connecting the nozzles to a source under constant pressure through control valves. The form and volume of the solvent delivered to the capsule are regulated by means of a control device of the ΕΤΌ-type valve by regulating the time during which the valve is open and the pressure in the pressure source. To prevent the supply of solvent at times when this is not required, additional blocking valves may be included in the solvent supply line.

The system usually supplies liquid volumes in the range from 20 to 200 μl per capsule, the pressure is in the range from 1 to 5 gauge bars, the spraying time is between 0.1 and 1 s, depending on the size and material of the capsules.

The velocity and volume of the solvent flow into the annular space around the capsule can be adjusted to achieve the desired shape to ensure uniform penetration of the solvent into the gap between the cap and the housing. This includes modes of the high-speed mode for forming aerosol mist, a medium-speed mode for forming a liquid jet onto the surface, and a low-speed mode for forming a ring of liquid that extends just enough to touch the capsule.

The system provides more solvent to the capsule than can be absorbed by the gap, in order to ensure that the entire area is well supplied with a solvent. Excess solvent is removed from the space around the capsule by vacuum suction and / or air jets. This action is also monitored by PbC, and the air / solvent mixture is removed from the area around each capsule through an additional line of holes adjacent to the spray nozzles. These openings are interconnected by a second piping system and are connected to a spray boom, i.e. connected to a vacuum pump and a trap tank in which solvent vapors may condense and liquid may be trapped.

Upon completion of spraying the solvent and removing its excess capsules are in a state where the solvent is in its place in the gap, but the capsules themselves are still sticky as a result of the solvent acting on the external surfaces. Further, the capsules must be dried under carefully controlled conditions so that the junction is formed correctly and the capsules do not stick together or do not receive cosmetic damage due to adhesion to other surfaces.

The method by which this is achieved in a preferred embodiment of the invention is to rotate the spray bar and move it away from the feed tubes in order to center the capsules relative to the inlets of the drying basket. This is achieved by installing a spray boom in a cylinder that can rotate. To remove the capsules from the spray boom, the cylinder is rotated 120 °, and the capsules are ejected using a combination of push rods and air jets. The capsules fall down along separate collecting tubes, inclined at an angle of 60 °, into one end of the drying basket.

In order to maintain high throughput, the cylinder on which the spray rods are mounted has attachments for 3 spray rods, spaced from each other at a 120 ° interval. The rotational movement that ejects the capsules delivers a new spray bar 13 under the feed tubes, ready for the start of the new cycle.

An additional element allows the cylinder with the spray rod to rotate in the opposite direction, when a command from PBC is given to it and the capsules are ejected onto a separate gate, which does not feed them into the cylinder, but into a separate outlet. This allows the capsules to be removed from the machine after sealing, but before drying, in order to carry out diagnostic or measurement procedures.

In order for the machine to work with capsules of various sizes and at the same time maintain precise control, both the feeding of the capsules and the sealing procedure, it is necessary to make some changes in the equipment that allow one to adapt to changing the size of the capsules. In a preferred embodiment of the invention, these changes are limited to a small number of easily accessible elements, such as a delivery tube assembly, spray booms and an exit sieve.

In addition, to ensure that the machine functions correctly, a number of sensors can be used to ensure that capsules and liquids are available and properly transported. These sensors include an optical sensor at the input bin to determine the presence of capsules, fiber optic sensors in the pipes between the spray rods and the drying cylinder, pressure and vacuum sensors at appropriate locations, as well as fluid flow sensors.

The basket into which the capsules are ejected after filling, contains a tubular system with open nets and with internal spiral guides. The cylinder slowly rotates, so that the internal spiral causes the capsules that fall on it from the sides, when they are raised by this rotation, to move along the axis of the cylinder. In this way, the capsules gently tilt around the cylinder, moving along the spiral path of the inner spiral guide (s).

Functions of the drying basket

The conditions under which the capsules are dried after the solvent has been introduced into the gap are critical for achieving good sealing. The key actions to be performed during the drying process are:

the capsules are transported through the drying zone to a storage container in bulk;

the time that the capsules are in the drying zone is controlled in such a way as to ensure that the capsules are sufficiently dry at the entrance to the storage container in bulk so as not to stick to each other;

air blows the capsules on all sides in order to achieve fast uniform drying;

contact of the capsules with each other is minimized to prevent them from sticking to each other;

capsule contact with the basket is minimized to prevent sticking to the walls; and the mechanical impact load on the capsules is minimized to prevent damage.

The drying basket in the preferred embodiment, has a design that includes a cylindrical structure, mainly made of stainless steel mesh. The inner part, which preferably consists of a double helix guide, is also made of stainless steel.

The dimensions of the cylinder are preferably from 600 to 1000 mm in length with a diameter between 100 and 200 mm, while in the preferred embodiment of the invention the length is 800 mm and the diameter is 160 mm. The ratio of the diameter to the length is chosen to control the mechanical characteristics, the length is a function, the required duration of stay in the drying zone, and the diameter is a function of the number of capsules processed.

In the present embodiment of the invention, with the dimensions established above, the length is chosen such that the residence time of the capsules in the drying basket is from 10 to 100 s.

The cylindrical drying basket is oriented horizontally with its axis. In a preferred embodiment of the present invention, the basket is held by rollers, which allows it to freely rotate around a horizontal axis. The rollers can be made to provide a sufficient number of functions, allowing one of the rollers to be actuated to cause the basket to rotate, or the drive can be fed directly to the basket by coupling at one end. The methods of attachment and transfer of rotational motion should ensure free air flow through the basket and be compatible with the requirements of cleaning and maintaining cleanliness.

In one embodiment of the invention, the inner double helix has the function of causing the capsule to tip over in one axial direction as the basket rotates. The angle and shape of the helix are critical to ensure that all capsules are transported axially at the same speed. In this embodiment of the invention, the spiral is made of blades having a span from the central shaft to the cylinder grid. Each blade consists of two shoulders with a swing in diametrically opposite directions from the central shaft to the cylinder grid. Each blade is mounted on a shaft rotating at a fixed angle relative to its neighbors. This angle is usually 12 °. Blades are made by stamping from stainless steel sheets, usually 0.75 mm thick, and can be coated with polytetrafluoroethylene to provide low surface energy. The connection of the blades with the shaft and the cylinder is performed using mechanical clamps provided in their designs. To ensure this, the shaft has annular grooves for placing the blades at a distance selected to provide the desired pitch of the helix. This pitch is typically 5.993 mm with 118 blades, which results in a double helix structure with a pitch of 179.8 mm. The shaft has flat sections located on diametrically opposite sides, and the blades have corresponding profiles of central holes, so that the blades can slide along the shaft and be fixed in the desired groove on the shaft by rotation. The blades are connected to the cylinder using grooves on the outer profile of the blades, which are aligned with axial wires attached to the inner side of the cylindrical mesh. In a typical embodiment of the invention, 30 wires are used, separated from each other by 12 °, which corresponds to the arrangement of the blades. The blades are installed in the basket by sliding the blades along the shaft and rotating until they lock into place. The outside mesh of the cylinder is designed to combine the functions of holding the capsules and providing connecting clamps for the blades, while at the same time maximizing the open surface to ensure good air blowing. To achieve this, 134 separate rings of 0.16 mm diameter wire, made of stainless steel, are bonded by circumferentially welding to 30 longitudinal 0.2 mm diameter wires, made of stainless steel and arranged to form 121 increments around the circumference. The longitudinal wires are inside the ring wires, so that they act as fasteners for the blades.

In an alternative embodiment of the invention, separate baskets are used mounted outside the individual sections, which allows for their easy removal. In this embodiment, a 3 cm spiral design is used, such that each spiral has a pitch of 240 mm and the basket has an internal diameter of 185 mm. The outer part of the basket and the spiral blades are made of flat forged products, each with three blades formed in it and with a serrated rim, so that when placed together with a stack with a shift of 6 ° around the central shaft, the serrations are spaced approximately 4 mm and form an internal spiral with the required pitch. The known elements interlock the sections together, allowing the drive to rotate all sections from one end.

The design of the drying basket in the above-described embodiments of the invention are examples of the means by which the required transport conditions are achieved when capsules pass through the drying zone. This idea can also be implemented through the use of a number of design solutions and design techniques. These include, but are not limited to, baskets with rectangular sections with flat partitions, angled to each other and placed in such a way that, when the basket rotates, the capsules move up the basket in one direction, as shown in FIG. 2

The use of rectangular sections can significantly reduce the cost of production.

Another alternative is to use a belt conveyor system where the belt conveyor has an open mesh structure that allows air to circulate around the capsules, in which either an air jet or a tube to discharge the capsules can be used to prevent the capsules from sticking to each other or to the belt. countercurrent air, where warm air is supplied to the lower part of the vertical pipe at a speed chosen so that the weight of the capsules is slightly greater than the aerodynamic resistance upward air jet. Thus, the downward movement speed of the capsules can be adjusted by adjusting the air velocity, which results in a time of flight sufficient to dry the excess liquid.

In a further preferred embodiment of the cylindrical drying basket, the central element has 3 blades forming 3 interlaced spirals arranged in relation to each other at such an angle that the number of turns along the drying basket length is between 2 and 4.

Since both the outer cylinder and the spiral vanes are made of open mesh, this allows the air flowing through the drying basket to freely mix with the capsules.

To hold the basket, the latter is placed in a covering container of solid material with ventilation holes for air inlet and outlet. Air enters through two or more axial slots at the base of the basket. The size of the slots is chosen in such a way as to provide the incoming air with a high speed sufficient to detach the capsules from the inner surface of the basket in order to enhance the tilting action and to ensure that the capsules never stick to the walls and to each other. The air leaves the chamber through the openings located in the opposite side of the supply of capsules.

The air supplied to the drying basket comes from a compressor device capable of supplying large volumes of air at high speed. To bring the air temperature to the required, heated or cooled heat exchangers are installed between the compressor and the inlet slots. The air entering the compressor from the room increases its temperature by compression, that is, even without additional conditioning, it will enter the drying device, having a temperature from room temperature to room temperature by 30 °. By heating or cooling, the temperature can be adjusted in the range from 5 to 80 ° C. The cooling heat exchanger is preferably an air-water system, similar in shape to that used in automobiles. Pumping out of the drying basket is carried out with an additional large-volume air pump, which directs air and solvent vapors along the pipeline structure beyond the machine.

The exhaust air can then be diverted either to the room, to the outside air through ducts and exhaust pipe, or to the evaporator / scrubber to remove the solvent and condition the exhaust air to release it.

The choice of emission system depends on the place of work and the solvent used.

The use of pumps for supplying and removing air makes it possible to adjust the pressure in the basket. Where it is necessary to avoid the release of solvent into the surrounding air, it is important that in all places inside the dryer the pressure is less than the pressure in the room. The PlyC can control the motors that drive both pumps, and thus independently regulate the pressure and flow rate.

The use of a spiral in the drying basket means that the residence time of the capsule in the drying basket is regulated simply by changing the speed of rotation. When the capsules reach the end of the basket, they fall into a sieve and are dropped into a storage container or transport mechanism.

If the solvent used should not be discharged into the atmosphere of the room, additional elements may be included in the system to ensure that all solvent is removed by air blowing. These elements include guide screens around the spray boom cylinder, which form a substantially closed volume connected to an air pump to ensure that all the fumes separated in this area are removed, a transparent guide screen to install the supply pipe to the place giving the operator’s ability to see the spray rods with the solvent poured into them before the start of the sealing cycle to visually check the functioning of the system, balancing the air flow with pressure to ensure that all solvent-containing volumes are below atmospheric pressure, the location of the air flow at the outlet, giving the capsules the opportunity to exit without loss of solvent vapors, while in extreme cases the capsules leaving the drying device can be placed in an airtight container through which air is blown in order to remove residual solvent vapors, control interlocks to prevent access, for the time after spraying, to the parts participating in the liquid supply machines that allow air streams to remove residual solvent vapors, and / or the selection of all materials in contact with liquid or solvent vapors to prevent their destruction as a result of prolonged use.

Claims (11)

1. The method of sealing hard-shell capsules having coaxial parts of the body that overlap when telescopic connected to each other, thereby forming a gap around the contour of the capsule, comprising the steps of individually supplying a sealing fluid including a solvent uniformly to the outer edge of the gap of the capsule to be formed to form rings from the fluid around the capsule outline, removing excess sealing fluid from the outside of the capsule, drying the capsule by applying heat energy from the outside while carefully tipping capsules and transporting them along a spiral path. 2. The method according to claim 1, in which the excess sealing liquid is removed using the combined effects of air jets and suction. 3. The method according to claim 1 or 2, in which the flow rate during the supply of the sealing fluid is controlled so that a ring of fluid is formed, which stretches to the size just to touch the capsule. 4. Apparatus for sealing hard-shell capsules having coaxial parts of the body that overlap when telescopic connected to each other, thereby forming a gap around the capsule contour, including means for individually supplying a sealing fluid, including a solvent, uniformly to the outer edge of the gap of the capsule to be sealed for the formation of a ring of liquid around the contour of the capsule, means for removing excess sealing fluid from the outside of the capsule, means for drying I capsule by applying thermal energy from outside while accurate rollover capsules and transporting them in a spiral path. 5. The apparatus according to claim 4, wherein said means for individually supplying a sealing fluid include a plurality of spray nozzles uniformly spaced around the circular contour of the capsule and directed toward the outer lumen of the overlap gap, and means for controlling the temperature of the sealing fluid, capsule and atmosphere in the gap. 6. The apparatus according to claim 4 or 5, in which the said means for drying the capsules include a rotating cylindrical drying basket with an internal blade system located along the axis of the cylinder and arranged in such a way that when the drying basket is rotated, the capsules capsize and transport along a spiral path. 7. The apparatus according to claim 6, in which the specified cylindrical drying basket is surrounded by a container with solid walls with ventilation holes and means are provided for supplying conditioned air in large volumes and at high speed to the drying basket. 8. The apparatus according to claim 6 or 7, in which the specified drying basket has a rectangular cross-section and partitioned at an angle to each other as an internal blade device. 9. A capsule having hard shell coaxial parts of the housing that overlap when telescopic connected to each other, sealed by the action of a solvent supplied to the overlapping region, in which separation elements are provided to ensure a uniform gap in the overlapping region, while these separation elements are designed so that they soften under the influence of a solvent, so that the gap closes in this way. 10. The capsule according to claim 9, in which sealing is provided at the end of the gap facing the inner region of the capsule, to prevent leakage of product filling the inner region into said gap. 11. The capsule according to claim 9 or 10, in which the product filling the inner region is immobilized to prevent it from flowing into the specified gap.