EP0813472B1 - Device for producing tablets - Google Patents

Description

The invention relates to a device for producing tablets or compacts according to the preamble of claim 1.

A pressing device for pressing coal briquettes with the subject Features of the preamble of claim 1 is already from US 1,448,982 known in 1923. Such a briquette press is usually pulverized Coal pressed into briquettes together with a suitable binder.

From FR 2 397 227 a device for pressing feed is known from the press ram to form a compact by means of a controlled by setting discs Lever mechanism are movable.

Automatic devices for the production of tablets are based on the principle that a tablet is compressed into a tablet due to a pressing process. For this purpose, two movable punches serve as pressing tools. Known automatic Devices for producing tablets have a lower stamp aligned vertically, that runs in a die and an upper stamp that only goes into the die Pressing is introduced. The upper punch slides into the die, pushes the powder together and squeezes the tablet. Thickness, strength depend on him and his pressure and press gloss of the tablet. Leave the insertion depth and pressure level regulate oneself. The lower stamp is located inside the die. It limits the filling space down. During the pressing process, it usually forms the counter bearing. After completing the pressing, it is brought up and brings thereby the tablet on the edge of the die, where it is pushed aside. In the next bar the lower die falls back into its initial position and the die space is closed Ready for the next filling. The matrices are filled using a Filling funnel, the bottom part of which is called a filling shoe.

These known devices are usually used as rotary tablet machines today educated. In these types, the filling shoe of the hopper is fixed while the die is movable. A round horizontal plate carries a number of matrices. As previously stated, each die has an upper and a lower stamp. The stamps are raised and lowered by rolling. By rotation In a horizontal plate, the dies are successively filled with their stamps Position brought under the filling shoe.

• Eine intensive Vorbehandlung der zu verpressenden Substanzen ist notwendig, um ein gutes Fließverhalten und damit die Dosierbarkeit zu erreichen.
• Das Füllprinzip (fixierter Füllschuh auf rotierendem Matrizentisch) hat zur Folge, daß relativ hohe Materialverluste hingenommen werden müssen und durch die am Füllschuh vorzusehenden Dichtleisten, beispielsweise Metallabrieb ins zu fertigende Produkt gelangt. Es entstehen die sogenannten schwarzen Flecken auf der Tablettenoberfläche.
• Im Preßraum der Vorrichtung entstehender Staub wird zunächst auf den freien Oberflächen der gefetteten Oberstempel abgelagert. Er fällt bei andauerndem Prozeß ab und gelangt über den Matrizentisch in den Füllschuh. Auch dieser Effekt führt zu den bereits zuvor genannten "schwarzen Flecken" auf der Tablettenoberfläche.

From a process technology point of view, rotary tablet machines have some serious shortcomings that cannot be completely remedied due to the above-described design principle of the device. The main drawbacks in the manufacture of tablets for pharmaceutical purposes or pressed tablets in the food sector are:

• Intensive pretreatment of the substances to be pressed is necessary in order to achieve good flow behavior and thus meterability.
• The filling principle (fixed filling shoe on rotating die table) has the consequence that relatively high material losses have to be accepted and through the sealing strips to be provided on the filling shoe, for example metal abrasion, reaches the product to be manufactured. The so-called black spots appear on the tablet surface.
• Dust arising in the press chamber of the device is first deposited on the free surfaces of the greased upper punches. It falls off during an ongoing process and reaches the filling shoe via the die table. This effect also leads to the previously mentioned "black spots" on the tablet surface.

The object of the invention is therefore a device for producing tablets or tablets to hand, with the tablets or tablets without the so-called "Black spots" can be produced on the tablet surface.

This task is based on a generic device according to the Preamble of claim 1 by the characterizing features of the main claim solved. The pressing tools, which are movable relative to one another, are conventional Tablet machines no longer aligned vertically, but horizontally. By this measure can effectively prevent the occurrence of the "black spots" become. The pressing tools are rotatable on one Rotor arranged. A pressure roller is mounted eccentrically to the axis of rotation of the rotor and on the edge of the rotating part of the device are two further pressure rollers arranged so that over the eccentric pressure roller and the other two Pressure rollers the pressing tools arranged between them during the corresponding pass are pressed against each other.

There can be several equally distributed on the circumference of the rotor in relation to each other movable pairs of pressing tools can be arranged. The filling device can with be coupled to the rotor such that they rotate together with it is relocatable. The rotor and the filling device can be connected to one another via the axis of rotation be coupled. The filling device can consist of a bulbous shape Filling hoppers exist, on which funnel-shaped tapered channels are attached are, the tapered ends of which open into a filling opening of the respective die. This arrangement of the hopper allows the dies to be centrifugally applied be filled with the tablets. This can also cause poorly flowing Materials are processed well and it can be dosed more precisely.

The mutually movable pressing tools are advantageous during their rotation moved in the horizontal direction by guide curves assigned to them. As a result, a correspondingly assigned one can be used for certain angular positions Work cycle to be carried out.

The two other pressure rollers can be at a different distance the associated pressing tools can be arranged that a different strength Press pressure can be generated. This allows through at a certain angular position a first pressure roller can be used to pre-press and at a second angular position complete pressing can be done by the second pressure roller.

Fig. 1:

einen schematischen Schnitt durch einen Teil einer ersten Ausführungsform der erfindungsgemäßen Vorrichtung,

Fig. 2:

eine Draufsicht auf einen Teil der erfindungsgemäßen Vorrichtung gemäß Fig. 1 und

Fig. 3-5:

Detaildarstellungen, die verschiedene Arbeitsschritte der erfindungsgemäßen Vorrichtung erläutern.

Further details and advantages of the invention are explained in more detail with reference to an embodiment shown in the drawing. Show it:

Fig. 1:

2 shows a schematic section through part of a first embodiment of the device according to the invention,

Fig. 2:

a plan view of a part of the device according to the invention according to FIGS. 1 and

Fig. 3-5:

Detail representations that explain different steps of the device according to the invention.

The device shown in FIGS. 1 and 2 has one driven by a motor, not shown here Rotor 1, which rotates in the direction of rotation a according to FIG. 2 is relocatable. Aligned horizontally on this rotor in each case two pressing tools movably arranged relative to one another 2, 4 mounted. The pressing tools 2, 4 are in the form of a inner stamp 4 and an outer stamp 2 formed, the Immerse in a corresponding hole in a die 3. The circumference of the rotor 1 in the present exemplary embodiment four pairs of press tools with the corresponding dies interact, arranged. On a central axis A of the rotor 1, a material hopper 5 is additionally arranged, which rotates together with the rotor 1. During the rotation of the rotor 1, the outer press tool 2, i.e. the outer stamp, via an outer guide curve 12 (see FIG. 2) shifted relative to rotor 1 in the horizontal plane. As well the second press tool 4, i.e. the inner stamp, via a guide curve 11 during the rotation of the rotor 1 shifted in the horizontal plane of the rotor. Take this through the pressing tools 2 and 4 to each other depending on the Angular position of the rotor 1 based on the respective guide curves a different position to each other. this will based on the representation of FIG. 2 clearly.

In position I the two press tools are far apart away. Here, the tablets are filled and dosed. In position II, the pressing tools 2 and 4 are further moving towards each other. Here, the tableting material is becoming increasingly popular compressed. To apply the necessary pressing force, here two pressure rollers 6 and 8 are arranged opposite one another. The tablet is pre-pressed in this position or the compact within the die 3. In position III are the pressing tools II and IV on each other even further too moved, so that the tableting material is compressed even further becomes. Here is the final compression pressure to form the tablet reached. The final pressing pressure is through the pressure roller 6 and the pressure roller 7 applied (see FIG. 2). Finally the pressing tools are shifted by the cam control, that the finished tablet or the compact from the Die are ejected. This ejection position is in the Fig. 2 labeled IV.

The pressure rollers 6, 7 and 8 are adjustable. The in middle region of the rotor 1 is arranged pressure roller 6 arranged eccentrically to the axis A of the rotor 1, wherein its eccentricity is adjustable. The pressure rollers 7 and 8 are each adjustable in their distance from the rotor 1. Due to this adjustability, the pressing forces can form the tablet or the compact can be varied. Basically serve the pressure rollers 6, 7 and 8, as previously stated, to generate the necessary pressing forces and on the pressing tools transferred to. It comes with each passage of the pair of press tools 2, 4 between the respectively assigned pressure rollers 6 and 8 and 6 and 7 on the compression of the matrix content.

The filling device 5 is in the embodiment shown here designed as a bellied filling funnel, the funnel shape being formed by an inside of the hopper arranged cone is obtained. Between the hopper 5 and corresponding filling openings 10 in the matrices 3, funnel-shaped channels 9 are formed. Due to the centrifugal forces caused by the rotation of the Filling funnel on those located in the tapered ends Tablets particles act, is a safe promotion and thus filling the matrices 3 in position I guaranteed.

3-5 are different working positions the pressing tools 2 and 4 shown to each other. 3 the matrix filling phase is shown. This representation corresponds to position I in FIG. 2. In FIG. 4 the Compression of the tableted material shown. This corresponds to phase 2 positions II and III according to FIG. 2. Finally the output of the finished tablet T is shown in FIG. Phase III corresponds to position IV according to FIG. 2. Here it is clear that the finished tablet T by a corresponding Slit 13 downward due to gravity drop a collecting container, not shown here can.

Claims (6)

1. Apparatus for producing tablets or pressed articles, having at least in each case two movable pressing tools (2, 4), aligned horizontally in relation to one another, and at least one mould (3), which interacts with said pressing tools, and having a filling arrangement (5, 9) for feeding the tabletting material into the mould, the pressing tools (2, 4) being arranged on a rotor (1) which can be made to rotate, characterized in that a pressure-exerting roller (6) is mounted eccentrically in relation to the axis of rotation of the rotor (1), and in that two further pressure-exerting rollers (7, 8) are arranged on the border of the rotor of the apparatus, with the result that, via the eccentric pressure-exerting roller (6) and the two further pressure-exerting rollers (7, 8), the pressing tools (2, 4) arranged between them as they pass through can be pressed against one another.
2. Apparatus according to Claim 1, characterized in that a plurality of pairs of pressing tools (2, 4) which can be moved in relation to one another are distributed equally over the circumference of the rotor (1).
3. Apparatus according to Claim 1 or 2, characterized in that the filling arrangement (5) is coupled to the rotor (1) such that it can be made to rotate together therewith.
4. Apparatus according to Claim 3, characterized in that the rotor (1) and the filling arrangement (5) are coupled to one another via the axis of rotation.
5. Apparatus according to one of the preceding claims, characterized in that the filling arrangement (5) comprises a convex filling hopper (5) which is adjoined by channels which taper in a funnel-like manner and of which the tapered ends open out in a filling opening of the mould (3).
6. Apparatus according to one of the preceding claims, characterized in that the two further pressure-exerting rollers (7, 8) are arranged at different distances from the associated pressing tools (2, 4) such that it is possible to produce a compacting pressure of varied strength.

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