ITPI980035A1 - AUTOMATIC DOSING AND PRESSING MACHINE FOR POWDERS IN GENERAL, FOR THE FULLY AUTOMATIC PRODUCTION OF TABLETS, OR SIMILAR, OF VARIOUS - Google Patents

Description

Description of the industrial invention entitled: "AUTOMATIC DOSING AND PRESSING MACHINE FOR POWDERS IN GENERAL, FOR THE FULLY AUTOMATIC PRODUCTION OF TABLETS, OR SIMILAR, OF VARIOUS CALIBRATED DOSAGES, OF VARIOUS SHAPES AND SIZES, AND OF MULTIPLE DENSITIES"

DESCRIPTION

Basically, the invention consists in the easy, precise, safe and rapid "setting up" of the machine itself. The similar machines known up to now present great difficulties in their preparation (setting up) for the adoption of unsuitable kinematics and organs in order mainly to the phase of pressing the powders for the formation of the tablet destined to very narrow tolerances in volume and weight (density). In fact, the machines known up to now have organs such as eccentric collar, for the reciprocating motion for which the pressing punch is intended, an adjuvant flywheel the driving action substantially constituted by the large dimensions of the reduction gears (downstream of the engine), hence:

The above-mentioned collar eccentric presents a law of motion that is not appropriate for uses in which it is necessary to extend the pressing action to the inversion of the motion, while to reach the desired density of the powder, a pressing action tending to be distributed as much as possible rather than tending is required. to be focused. The invention, instead of the collar eccentric, adopts a cam with a mathematical law such as to achieve a more rational pressing action with less energy, moreover the cam member offers almost absolute rigidity, extremely necessary for strictly tolerated densities as in this case.

The machines known so far are characterized by the fact that the collar eccentric is actually constituted by a double eccentric for the realization of a calibration of the stroke of the pressing punch.

It should be noted that the double eccentric superscript being equipped with a sliding bearing (bushing) gives rise to radial play which occurs irregularly being a function of the reaction force that the powder exerts on the pressing punch.

Hence: the aforementioned flywheel effect, while assisting the drive action, does not occur when the operator manually "sets up" the machine. Therefore, in addition to the concentrated pressing harmful effect, the harmful effect derived from the variability of the game is also revealed, which turns out to be a function of the badminton effect.

For all of the above, the operator finding variations in the density of the tablet, from machine running to manually operated machine, takes a long time to "set up" the machine itself and without the certainty of correct continuity. Basically the machine, object of the invention comprises:

A gearmotor that drives a shaft on which two cams are housed, the first of which is equipped with two distinct profiles intended to operate the pressing punch in its active phase and to rotate a small fan to stir the powders near their entry into work.

A second cam (positive cam) that manages the vertical motion of a (lower) crosspiece intended to accommodate the precise volume of powder in an elevated position, while in the lowered position the above-mentioned lower crosspiece discovers the finished tablet by placing it "open" to allow a flexible organ (brush) to launch the tablet itself towards the collection channel. This last operation, of launching the tablet, is carried out, always from the same lower crosspiece and always in the aforementioned lowering phase, by means of the special device equipped with the the aforementioned brush and enslaved to the aforementioned lower crosspiece The aforementioned second cam also performs the function of handwheel for the manual movement of the machine mainly for the "setting up" phase of the machine itself. It should be noted that the invention allows the use of the aforementioned handwheel only for machine control thanks to the setting of the machine itself through parameters already prepared and settable with the aid of special valid manual devices, better described below.

The foregoing substantially constitutes the essence of the invention together with what has been described above.

The aforementioned manual devices intended for setting up the machine consist of manually rolling means, equipped with a finely graduated and numbered scale, referring to the relative guideline. Finally, it should be noted that the reaction to the pressing of the powders is controlled by an elastic system preloaded beyond the necessary nominal pressing force created by the first profile of the first cam acting on a roller integral with the pressing punch through the appropriate punch holder shaft and roller holder itself. The above in order to avoid accidental breakage and or excessive overloads to the pressing punch and to the motor, harmful effects evident in machines known up to now, since they are not equipped with said elasticity.

Furthermore, the machine, object of the invention, comprises a hopper for containing the powders waiting to be automatically placed in dosage and subsequently in pressing.

Note that the aforementioned hopper, equipped with a stirring fan for the powders in the vicinity of their commissioning, is subject to horizontal reciprocating motion made by means of a special wheel rigidly housed in the dust fan-stirring shaft. The second (cup) profile of the 1st cam, referred to on p. 3, last paragraph, synchronously performs the above-mentioned reciprocating motion by acting on the aforementioned wheel, with its own shaft anchored to the hopper. Motion, the latter, which operates as an alternative to the vertical reciprocating motion of the pressing punch which is subject to the 1st profile of the first cam as mentioned on page 3, last paragraph.

The invention will be better understood by following the description and the attached drawing, which shows a practical non-limiting example of the invention itself.

In the drawing:

Fig. 1 shows the front view of the whole machine with the two adjustments intended for the prescribed and determined density of the tablets.

It should be noted that the resulting density is a function of the volume of the powder fed into the work and of the pressure exerted by the pressing punch. Hence the usefulness of the two relative precise adjustments described above, which allow the rational use and the safe valid continuity of the machine.

Fig. 2 shows the side view of the whole machine which is particularly indicative of the two positions of the hopper which, as already explained, are an alternative to the positions of the pressing punch.

Fig. 3 shows the plan view where the motorization and the hopper are highlighted, which, being anchored to the lower plate, undergoes the raising and lowering motion produced by the 2nd cam which also performs the function of handwheel for the " point "of the machine. Note also the queuing (2 columns) intended for the above-mentioned handling.

Fig. 4 shows the device intended for adjusting the volume of powder to be pressed by means of the upper pressing punch, while the lower punch fixed but vertically adjustable with the aforementioned device performs the reaction to the pressing.

Fig. 5 is a side view of the whole machine to particularly illustrate the hopper constrained at the bottom on a removable shaft, together with all the equipment constituting the hopper itself, and constrained at the top radially by two bearings placed in part fixed and precisely mounted on shafts coming out of the upper fixed crosspiece described below. It should be noted that the above-mentioned Fig. 5 shows the hopper in a non-active position, ie excluded and set back with respect to the upper pressing punch which thus has the possibility to operate. It should also be noted that the hopper being on the edge of the lower plate, which is subject to vertical motion as already explained, is equipped with constraints, specified below, which allow it to remain in the excluded position even during the vertical motion described above. Finally, it should be noted that the hopper is also managed in its own horizontal inclusion and exclusion motions both by the aforementioned lower shaft, where it can slide, and by the two above-mentioned upper bearings, since they can also provide continuous vertical constraint during the entire stroke. descent and ascent generated by the lower plate to which the hopper is anchored.

Fig. 6 is a side view illustrating the cycle start phase: pressing punch excluded, hopper excluded, '' brush "for compressed ejection, at the end of its active phase to be still subject to the reaction of the underlying contrast media, therefore lower crossbar in the lowered position for allowing the "brush" to have intervened on the tablet thus placed: tablet already launched therefore towards the collection channel.

Fig. 6 shows the second (positive) cam engaging the idle pin which carries out the raising and lowering motion for the lower crosspiece intended to accommodate powders in a calibratable manner and to open the completed tablet with its lowering. Furthermore, Fig. 6 shows the device for adjusting the active stroke of the pressing punch, stroke that can be adjusted by means of the special finely graduated disk.

Fig. 7 shows section A-A in Fig. 6 to illustrate the two seats of the two bearings acting on the lower crosspiece, mounted on two arms connecting centrally on the hinge to make equal and applied on the axis of the lower crosspiece the two forces exerted by the two bearings themselves which are subject to the force of the first cam which, through the means indicated, acts on their bearings.

Fig. 8 shows the two scrapers intended to prevent the dust from escaping, since they can be shaved both on the surface and on the four sides, thus avoiding the rigid rubbing of the hopper contour.

Fig. 9 shows the 1st cam with its two profiles.

Fig. 10 shows the 2nd cam (positive).

Fig. 11 shows the suitably graduated disk for adjusting and calibrating the upper pressing punch.

Fig. 12 shows the graduated bushing for adjusting and calibrating the lower punch intended to remain fixed after calibration.

SEQUENTIAL CYCLE:

1) Start cycle. Hopper advancement (with pause during the powder loading phase).

1a) At the end of advancement: stop for rotation of the mixing fan and for loading powders into the appropriate compressed formation jacket. Fan rotating only with hopper stopped for powder loading.

2) Return of the hopper and stop of the hopper itself in the excluded position.

3) Lowering of the pressure punch and formation of the tablet.

4) Elevation of the pressure punch until it is completely returned to the excluded position and simultaneous lowering of the lower crosspiece carrying the compressed formation jacket until usefully uncovering the tablet intended for the collection container and launched there by means of the ejector '' brush ".

5) End of cycle: hopper and presser parked, return elevation of the lower crosspiece.

In the drawing :

With 1 (table 1) the base is indicated.

With 2 the two supporting columns are indicated.

With 3 the lower crosspiece is indicated.

4 indicates the two seats where the bearings 5 act (table 7) destined to move the lower crosspiece 3.

6 indicates the unit for adjusting and calibrating the lower contrast punch 7 (table 4).

The reference 8 indicates the support for the seats 9 housing the springs 10 intended for the elevation of the movable crosspiece 11 and therefore for the elevation and exclusion of the upper pressing punch 12 (Table 2).

With 13 (table 1) the gearmotor is indicated.

14 indicates the regulator and setting unit for the upper pressing punch.

15 indicates the fixed upper crosspiece where the main shaft 16 is housed (table 2).

Numbers 16 and 17 (Table 1) indicate the pulleys for transmitting the motion from the gearmotor 13 to the main shaft 16 (Table 2).

With 18 are indicated the two columns which, by means of their connecting crosspiece 19 (table 1), support the support 20 for the roller 21.

With 22 (table 1) the hopper is indicated.

22A (Table 2) indicates the hopper in the "rest" position, ie excluded to allow the upper pressing punch 12 to descend into operation.

22B (table 2) indicates the hopper in advanced working position.

23 indicates the group which constitutes the support fulcrum of the hopper whose hub 24 is equipped with 2 linear ball bearings 25. 26 indicates in section a flat profile at the end of which springs attached to the bushing 27 intended for maintain contact between the second profile 28 (tav.2) of the cam 29 (tav.2-3) and the roller 30 (tav.13), equipped with rubber rings 31 (tav.13).

Reference 32 indicates the bearing which together with another identical bearing 32 create the radial constraint to the hopper 22 by means of the detail 33 integral with the hopper itself 22. It should be noted that the above-mentioned two bearings 32 are mounted on the two relative shafts 34 (tab. 2) fixed to the fixed upper crosspiece 15 (table 1).

35 indicates the graduated disk for adjusting and calibrating the upper pressing punch 12.

The number 36 indicates the bushing on which the overwritten graduated disc 35 is fixed, which is rigidly connected to the wheel 38-eccentric 39 assembly by means of the special tab interposed between the overwritten bushing 36 and the shaft 40 on which the screw 37 is mounted for axial locking of the above components.

41 indicates the second cam with positive profile 42 which, acting on the roller 21, moves the shaft 43 connected to the hubs 44 and 44A intended to house the two wheels 5 (table 7), intended to rationally move the lower crosspiece 3 (table 1 -2-6-7).

With 45 (table 4) is indicated a bushing, punch guide 46-47, housed in the lower crosspiece 3.

48 indicates the tablet being pressed.

Number 3 indicates the lower crosspiece in the elevated position "E", i.e. in operation intended for lowering until it reaches position B to open the tablet 48 destined for the collection duct 49 (table 5), as described below .

With 46 the upper pressing punch is indicated and with 47 the lower contrast punch made fixed after calibration and initial adjustment. With 50 (table 5) is indicated a kinematics intended to throw the tablet 48 (table 4-5) into the collection duct 49 (table 5).

51 indicates a "brush" moved by the overwritten kinematic mechanism 50 (table 5) intended to launch the tablet into the collection duct 49.

52A indicates a roller in a virtual position corresponding to the brush 51 in the capsule ejection end position. It should be noted that the above-mentioned roller 52A actually assumes the position 52A itself with the lower crosspiece in position B (table 4). Therefore the kinematic has a stable position in 52C and an unstable position in 52B and 52C. It should also be noted that positions 52B and 52C correspond to the descent of the lower crosspiece 3 (tables 1 -2-3-5).

53 indicates a terminal as the limit switch of the above-described kinematics 50.

Number 54 (table 4) indicates two packs of cup springs intended to protect both the upper pressing punch 46 (table 4) and the lower fixed contrasting punch 47 (table 4).

With "s" (table 4) is indicated the quota within which the machine is protected in relation to any accidental erroneous "set up" of the machine itself, ie due to an excess of attempted adjustment in relation to the pressing of the tablet. However, in this case the machine, since the gearmotor is equipped with a built-in torque limiter, will not be damaged.

With 55 (table 5) is indicated the bushing equipped with screws 56, which stop its slave position after adjustment, it is intended for the adjustment and calibration operation being equipped with a suitably and finely graduated scale.

With 57 and 58 (table 5) and the nut screw 58 which carry out the calibration and adjustment of the lower contrast punch 47.

59 (table 4) indicates the lever for locking screw 57 at the end of calibration.

With 60 (tables 2-5) is indicated the threaded knob that blocks the hopper unit in the working position.

The table 9 shows the first cam with the two profiles for managing the upper pressing punch 46 (table 4) hopper 22 (tables 1-2-5). The table 10 shows the second cam with a positive profile for managing the lower crosspiece 3 (tables 1-2-4).

The table 11 shows the suitably graduated disk for the calibration and adjustment of the upper pressing punch 46 (table 4).

The table 12 shows, in external view, the unit for adjusting and calibrating the lower contrast punch 47 intended to calibrate the precise volume of powder intended to be compressed to form the tablet.

Claims (15)

CLAIMS 1) Automatic machine (shearing and pressing machine for powders in general, for the totally automatic production of tablets, or the like, of various calibrated dosages, of various shapes and sizes, and of multiple densities, characterized by the fact that it includes the main kinematics made with two distinct cams, one of which has two profiles and both cams made integral with the motorized main shaft. 2) Machine as per the preceding claim, characterized by the fact that the first cam uses the first profile for the actuation of the pressing punch, while the second profile is intended for the insertion of the hopper containing powders into operation and for the disengagement of the hopper itself. 3) Machine according to the preceding claims, characterized in that the two profiles of the first cam act directly on a roller, equipped with a roller bearing, and on normal planes. 4) Machine as per the preceding claims characterized by the fact that the second cam has a positive profile and also acts on a rolling roller of rollers. 5) Machine according to the preceding claims characterized in that the second cam is intended for the vertical movement of the lower crosspiece with the hopper on board. 6) Machine as per the preceding claims characterized by the fact that the lower crossbar, being movable, allows the lower punch, in contrast to the upper pressing punch, to remain fixed although subject to calibration, therefore sliding but only during the setting up of the machine, that is, only in the powder dosing phase and therefore not in operation. 7) Machine according to the previous claims characterized by the fact that the lower contrast punch is constrained in the vertical direction, pressing direction, by groups of cup springs preloaded beyond the nominal pressing force necessary in order to avoid breakages and / or heavy harmful stresses to the pressing punch and to the lower contrast punch this also in the "setting up" phase. 8) Machine as per the preceding claims, characterized in that it comprises a central screw-nut screw device for adjusting and calibrating the lower contrast punch. Said adjustment is enslaved by a button, such as a nut screw, equipped with a circumferential graduated scale referring to various longitudinal guiding lines for identifying the level reached in the predetermined and limited vertical adjustment range. 9) Machine as per the preceding claims, characterized by the fact that the entire unit comprising the hopper is made removable by removing the appropriate threaded knob which secures the hopper in the working phase. 10) Machine as per the previous claims characterized by the fact that the hopper is constrained by its support fulcrum and radically by two bearings, partly fixed, which keep the hopper radially constrained both in the horizontal and in the vertical direction according to which the the hopper itself is destined to move also to be on board the lower mobile crossbar. 11) Machine according to the previous claims characterized by the fact that the roller subject to the action of the first profile of the first cam is mounted "by force" on the pressing punch holder shaft with an eccentric bushing that is rigidly interposed between the roller itself and the relative centering pin keyed into the punch holder and locked there. 12) Machine as per the previous claim characterized by the fact that the upper pressing punch is adjustable and calibrated in the vertical working direction by manual rotation of the pin-fulcrum of the wheel, as per the previous claim, rotation, the latter, enslaved to a disk graduated with a particular scale calculated according to the irregular eccentric effect. 13) Machine according to the preceding claims, characterized in that the hopper is equipped with perimeter elastic shaving devices acting on the powder deposit surface to avoid rigid contact of the hopper itself. 14) Machine as per the preceding claims, characterized by the fact that the load-bearing structure is made of a rigid base which suitably limits its own bending deformations. Two columns engaging in the base constitute the support for the crosspieces on which all the contour means are housed, while the unit that includes the lower punch in contrast to the upper pressing punch is fixed on the upper plane of the base, suitably elastic anti-vibration means are fixed on the lower floor of the base. 15) Automatic dosing and pressing machine for powders in general, for the totally automatic production of tablets, or the like, of various adjustable dosages, of various shapes and sizes and of multiple densities, all as described above and represented by example in the accepted drawing .