Rotary machines for the manufacture of tablets

Abstract: Improvements in rotary machines for the manufacture of tablets, consisting on a rotary assembly with multiple moveable rods that act in the corresponding formation chamber, provided with various outputs (8,9) for the tablets (10,11) produced around the periphery of the rotating portion of the machine, each of which outlets (8,9) receives the tablets (10,11) ejected from the different formation chambers in a previously programmed sequence of activation of the individual ejection rods during the tablet ejection phase by selective action on the ejectors associated with the various punches fitted to the machine.

Description: The present invention refers to a rotary machine for the manufacture of diverse types of tablets such as tablets of chemicals, food, pharmaceutical products, etc. The type of machines to which this invention refers consist of an assembly or rotating portion that rotates on a shaft that bears multiple elements to shape the tablets. These shaping elements are in turn made up of movable rods or punches, suitably guided in the rotating portion and which move inside a cylindrical formation chamber which receives the amount of material required to form the tablet, allowing the compression action to take place between the movable rods or punches and an upper counter-punch to form the tablet. The tablet is then ejected from the formation chamber via an outlet slide to continue to other stages of the production process, mainly packaging. GB-A-1053639 discloses an improvement to rotary tabletting machines providing a stationary deflector member associated with a stationary duct at the end of which a stationary deflector member diverts the tablets out of the matrix disc. However it does not provide or suggest the double set of camming surfaces combined with the movable rods to permit the separate programmation of the tabletting cycle and the ejection point for the tablets. The rotary machine for the manufacture of tablets object of the present invention is designed to provide greater versatility in the operation of this type of machines and possible increases in their productivity. In order to achieve these objectives, the machine described in this patent is fitted with means for pre-selecting, according to a determined distribution, the ejection of the tablets from the various shaping chambers in such a way that they be directed towards different production outlets. This system mainly consists of separate outlet slides for the manufactured tablets which direct them to different stations for packaging or handling. This provides an approach other than the current system of dividing the production of tablet making machines, and is especially useful for tablets that are not very consistent or fragile, increasing the effective production of the machine. Therefore, the present rotary machine includes the pre-selection of the ejection of the tablets according to a previously established program so that the different movable rods or punches that manufacture the tablets eject the same at a predetermined position on the periphery of the rotating portion of the machine. This assembly is fitted with various outlet slides for the finished tablets. The number of slides is not limited as it will solely depend on the previously determined ejection program. Any means may be employed to move the compression punches or movable rods to one or the other position on the periphery of the rotary unit, hydraulic, pneumatic, electromagnetic or mechanical, although the currently preferred system, and the one referred to in this description, is mechanical as they are usually used in this type of machine. In the same way, even though the number of outlets is variable, the example given here will concentrate on two outlets as an example. In the present embodiment, the machine includes the placement of separate means for activating the moveable rods, preferably by means of fixed cam surfaces placed in suitable positions, and forming sectors of a circle which is concentric to the rotating portion of the machine. The shape and relative placement of these cams enable the tablets to be ejected as programmed. These cams operate in combination with a system associated with the movable rods so that these latter eject the tablets when in contact with one or another of these fixed cams which, in turn, correspond to a selection of one or another of the multiple outlet slides. Two outlets in the case of the example described here. The following is a description of a preferred embodiment of a rotary machine for the production of tablets based on the following figures: Figure 1 shows a schematic top view of a rotary machine for the manufacture of tablets. Figure 2 shows a side view of part of the same machine as shown in Figure 1. Figure 3 shows a schematic view, with a partial section, of the rotating portion of the machine. The present rotary machine is described as an example of the mechanical operation of a machine for the production of tablets. However, as already mentioned, the scope of application is much wider, and includes other types of operation. In the event of using mechanical means, the present rotary machine is comprised of a rotating portion -1- fitted with a plate -2- that supports multiple moveable rods and punches -3- suitably guided in the plate and whose upper ends, usually enlarged into a compression head -4- fit inside cylindrical formation chambers -5- machined in an upper plate - 6-. The whole assembly rotates on a vertical shaft shown shaded and indicated by reference number -7-. Figure 2 shows part of the rotating portion -1-, as unwound on a plane, fitted with multiple movable rods -3-, -3'-, -3''-, ..., whose heads -4- are housed inside the upper cylindrical chambers -5-. The controlled movement of these rods -3-, -3'-, -3''-, ..., determine a variation in the volume of the chamber -5- above the head -4- suitable for receiving the material which is then compressed by the combined action of the counter-punch or a blocking plate not shown in the Figures. This will then allow for sufficient compression to form each of the individual tablets which then enter the ejection area. The present machine provides the previous programming of the ejection stage of the different movable rods -3-, -3'-, - 3''-, ..., in such a way that the tablets produced are ejected in a predetermined manner into different outlets located at certain positions distributed around rotating portion -1-. As shown in Figure 1, the example has two possible independent outlets -8- and -9- each consisting of an outlet slide that receive the tablets (indicated schematically by the numbers -10- and -11-) expelled by the ejection stroke which takes place at a predetermined position on the periphery of rotating portion -1-. This distribution enables the machine to be much more versatile as it may be used to manufacture tablets of different types which are ejected to the different outlet slides fitted to the machine, or even increase performance by ejecting tablets with the same composition from different outlets, enabling greater input to the final handling machines, usually packaging machines. The rotary machine object of this invention could also be applied to different types of packaging, with a different number of units per package. In the case of the mechanical configuration shown in the drawings, the pre-selection of the action of the movable rods -3- could be made by various fixed cams mounted on a base -12- on which the rotating portion -1- turns. This means that the ejection will take place when the movable rod -3- passes over each fixed cam placed in an angular distribution with the corresponding offset between phases. For example, the fixed cam -13- is represented as formed by an inclined entry plane and a zone of maximum height and flat profile -14- which coincide with the side rollers -15- of the movable rods -3-, -3'-, -3"-, ..., destined to eject the tablet by one of the machine outlets. For example, Figure 2 shows the movable rods -3-, -3'-, -3''-, ..., fitted with side rollers that are operated by the fixed cams -13-, - 14-. There is also another ramp also incorporating an inclined entry plane -16- and an area of flat profile -17- with an angular separation from the ramp -13-, -14-, and also with a radial separation to contact with the lower extremes of the movable rods -3- fitted with contact heads -18-. Figure 3 shows the radial separation between the fixed cam over which the heads -18- operate and the cam which activates the rollers - 15- so that each has a separate and suitably co-ordinated action on the movable rods causing the tablets to be ejected in the correct sequence to one or the other outlet ramp fitted to the machine. Obviously the number of outlets many be varied in combination with the number of fixed cams and elements fitted to the movable rods. Although the present invention has been described as, an example, having a mechanical configuration, it is to be understood that the invention is based on the location of various outlets for the tablets distributed in predetermined positions on the periphery of the rotating portion of the machine, which outlets are designed to accept the tablets in a pre-programmed sequence so that each tablet is ejected into the corresponding outlet. Therefore, pre-selection may be programmed by mechanical means as described here, or using any other method as the movable rods may be activated by pneumatic, hydraulic, electromagnetic or any other means. In this case the system for programming the ejection will correspond to the action system used, including electromechanical and electronic systems.

Claims: Rotary machine for the manufacture of tablets, consisting of a rotating portion (1) with multiple moveable rods (3, 3', 3",...) each acting in a corresponding formation chamber (5), the machine having various outlets (8) for the tablets produced distributed around the periphery of the rotating portion (1) of the machine, each of which outlets (8) receives the tablets ejected from the different formation chambers (5) in a previously programmed sequence of activation of the individual movable rods (3, 3', 3",...) during the tablet ejection phase by selective action on the movable rods characterised by the location of various fixed cams (14, 17) with a radial separation at pre-determined angles on a fixed base located below the rotating portion of the machine that act on the movable rods (3, 3', 3'', ...) to cause ejection of the tablets in a predetermined order and corresponding to the different outlets of the tablets produced. Rotary machine for the manufacture of tablets according to the preceding claims characterized in that the movable rods (3, 3', 3",...) are fitted with side rollers (15) activated by fixed cams (14) separated in a radial distribution.

Inventors: SITJAR CANELLAS RAFAEL, SITJAR CANELLAS, RAFAEL
Applicants: BONALS S A J, J. BONALS, S.A.
Application year: 1998
Main classification: B30B11
IPC codes: B30B11, B30B15