SU1594631A1 - Device for producing thin tablets of powder materials - Google Patents

Abstract

The invention relates to mechanical engineering, in particular to equipment for the production of articles from powders. The purpose of the invention is to expand the technological capabilities of the device and improve the quality of tablets by increasing the accuracy of dosing. In the device for the manufacture of tablets of powder materials between the fixed body and the movable upper head plate, an intermediate plate is interlocked with the mechanism for adjusting the height of the upper punch. This plate is spring-loaded with respect to the said hull and traverse and is connected with them by a hinged-lever mechanism. In order to improve the metering accuracy, the lower punch - ejector is made of two parts - a collar with a collar and a pusher, between which a spring is placed. The position of the pusher is regulated by the stop, driven by a stepper motor through a two-arm lever. After each pressing, the tablet weight is automatically measured and the position of the pusher is corrected. This avoids pressing defects. 5 il.

Description

The invention relates to mechanical engineering, in particular to equipment for the production of articles from powders.

The purpose of the invention is to expand the technological capabilities and the quality of the tablets by increasing the accuracy of dosing.

Figure 1 shows the device, a general view; Fig, 2 - the position of the elements when dispensing; on fig.Z the same, at consolidation of a dose; in fig. 4 - the same, when pressing; in fig. 5 - the same, under control.

The device comprises movable relative to the housing 1 and connected to the cam drive 2, the upper 3 and lower 4 crossheads rigidly interconnected by the columns 5. In the upper crosshead 3 is mounted for movement along the pressing axis. a rod with a flange 7, carrying at its lower end the upper punch B. Between the upper 3 and lower 4 traverses in the area of their joint movement in the housing 1 a block matrix 9 is mounted, in the working cavity of which the lower punch pusher 10 is located, including the rod 11 collar, spring 12 and pusher 13, interacting with an ejection drive of a compressed tablet 14. The device is equipped with an intermediate plate 15 mounted above the upper crosshead 3 and kinematically connected with it by means of two symmetrically hinged Chasna mechanisms 16, the axis 17 of which is fixed in the housing 1, In the central hole of the plate 15 there is a mechanism for adjusting the position of the upper punch 8 at a height that contains a sleeve 18 with a flange 19 and an adjustable stop 20 inside the sleeve 18 that is constantly in contact with the flange 7 of the rod 6, Flange 19 has a spherical surface that interacts during the pressing process of a tablet 14 with a reciprocal concave spherical surface made in the slab 15. The support 20 is connected to the upper crosshead 3 section 21 of the rifle, created together with the weight m upper punch 8 rod 6, upo ra 20 and the sleeve 18 a pressure sufficient for cooking before eating second sealing dose. The lower punch-ejector 10 is kinematically connected with the mechanism for adjusting the height of filling the powder material into the working cavity of the block-matrix 9, made in the form of a two-arm lever, whose swing axis 22 is fixed in the housing 1 in a plane perpendicular to the pressing axis. The arm 23 of the lever 22, with its fork end, interacts with the shoulder of the stern 11 of the lower punch 10 in the process of metered filling of the powder into the working cavity of the matrix. The shoulder 24 of the matched lever is compressed by the spring 25 to the adjustable stop 26, the position of which is set by the drive during the adjustment process, in the form of a step motor 27 connected to a control unit (not shown) of the device. The force of the spring 25 is chosen by the short circuit conditions for the contact of the shoulder 24 with the stop 26 in the process of filling the powder into the cavity of the matrix, as well as providing the possibility of returning the punch 10 after extruding the finished tablet 14 to the position of filling the powder. The spring 12 both pushes the kinematic closure of the mechanism for adjusting the height of the filling of the spray with the lower punch 10. On the housing 1 is mounted 28 with a powder material. By its bottom end, the hopper 28 tightly adjoins the upper plane of the slide gateway 29, reciprocating along the horizontal guides of the housing 1 under the action of the cam actuator 2. In the feeder 29, a socket 30dl of a portion of the powder material is made. The device is equipped with an automatic measurement system for deviations from the nominal lower position of the upper punch 8 after the extrusion of the tablet 14, containing the sensor 31 for axial movement of the upper punch 8 and the bar 32 attached to the flange 7 of the rod 6 and in contact with the probe 33 of the sensor 31c mounted on the housing 1 the lower position of the rod 6. The measuring system is connected with the control unit of the device and gives the signal to change the working position of the lever of the mechanism for adjusting the height of the powder material and by adjusting the position of the abutment 26, as well as the rejection of tablets whose weight does not correspond to the allowable value. The device works as follows. The operation cycle of the device begins with the filling of the powder material from the hopper 28 into the slot 30 of the dispenser 29. The upper 3 and lower 4 traverse are in the extreme upper position, the flange 7 of the rod 6 rests on the upper traverse 3, and between the concave spherical surface of the plate 15 and the convex the spherical surface of the sleeve 19 is formed by the gap SG. In addition, in the initial position of the device, the pusher 13 of the lower punch-ejector 10 is in the extreme upper position determined by the corresponding cam of the actuator 2. At the same time, the arm 24 of the lever for adjusting the powder filling height is in contact with the stop 26. After switching on the cam drive 2 the dispenser 29 moves to the block matrix 9, and the pusher 13 lowers, as a result of which the lever of the adjustment mechanism rotates about the axis 22 under the action of the springs 25, overcoming the force of the spring 12, until it touches the shoulders and 24 stops 26. In this case, the lower punch-ejector 10 occupies a middle position along the cycle fixed by the lever arm 23, and the spring 12 ensures a constant contact of the arm 23 with the collar of the rod 11 of the punch 10.

In this position of the adjustment mechanism, the nest 30 of the feeder 29 is located above the working cavity of the block matrix 9 — a backfill is carried out.

Further movement of the dispenser 29 to the left is the cut-off of the dose of powder trapped in the matrix. In the process of cutting off the dose of powder, the front end of the dispenser 29 shifts the tablet 14 from the upper surface of the matrix 9.

After the dosing process is completed, the dispenser 29 is retracted from the working area to its initial position, after which the lower yoke 4 begins to lower under the action of the actuator 2. Simultaneously, the upper yoke 3 is lowered with the rod 6 and the height adjustment mechanism of the upper punch 8, while the flange 7 of the rod 6 rests on the upper yoke 3. In the process of lowering the traverse 3 and 4, the levers of the mechanisms 16 are straightened, lowering the plate 15 at a speed lower than the speed of movement of the traverse 3 and 4. As a result, between the concave spherical surface of the plate 15 and the convex spherical surface of the flange 19 of the sleeve 18 increases the gap. After touching the upper punch 8 is in the cavity of the block matrix. 9 doses of powder and with further lowering of the cross arms 3 and 4 a gap is formed between the flange 7 of the rod 6 and the upper traverse 3. At this, the springs 21 begin to stretch and the force of the pressure on the dose is determined by the total weight of the rod 6 with the punch 8, the stop 20, the sleeve 18 and the force of the spring 21. After the formation of a gap. the lower punch 10 begins to vibrate from the cam,. which contributes to the compaction of the powder dose in the matrix. After compaction, the upper punch 8 stops, and the traverse 3 and 4 continue to fall, resulting in a larger clearance L, a gap

is selected, and the pressing force reaches its maximum. Under the influence of increasing pressing force on the pressed mass, the rod

 11, overcoming the force of the spring 12, is lowered to. resting its collar into body 1, to which the pressing force closes. From now on the bar

Q 32 is in contact with the probe 33 of the sensor 31. The pressing process begins. During the pressing process, the lever arm 24 is pressed by the spring 25 to the stop 26, and the arm 23 is in the lowest position, and the contact between its fork end and the collar of the lower punch rod 10 is missing, as a result, the loads on said tuning mechanism are not transmitted.

After the extrusion is finished, the actuator 2 switches to reverse, and both traverses 3 and 4 are raised. The upper punch 8 at the same time remains stationary and in contact with the finished tablet 14 due to the presence of a gap UQ between the flange 7 of the rod 6 and the upper traverse 3. In the process of lifting the traverse 3, the mechanisms 16 return to their original position, with the result that the plate 15 rises. a gap J is formed between the plate 15 and the flange 19 of the sleeve 18. Thus, the upper punch is left.

8 in contact with the tablet 14, the force on the tablet 14 is reduced to a value excluding the deformation of the tablet. In this position of the elements, the amount of deviation from the nominal lower position of the upper punch B is measured using a sensor 31, the probe 33 of which is in contact with the bar 32 the moment of arrival of the rod 6 in the lowermost

5 position. Since the reading from the sensor 31 is performed at a negligible pressure, the influence of elastic static deformations of the system on the measurement accuracy is excluded.

Claims (1)

After measuring the signal from sensor 31 to the control unit, the stepping motor 27 is turned on to change the position of the stop 26 to adjust the dose of the next batch of powder. Simultaneously with the adjustment of the dose, the rejection of the tablet 14, which was out of weight beyond the tolerance limits, occurs. After the measurement is completed under the action of the actuator 2, the pusher moves BBepXj by pushing the tablet 14 sandwiched between the punches 8 and 10, which excludes its deformation and destruction during pushing. After stopping the lower punch 10 in the extreme upper position and ejecting the tablet 14, the cross bars 3 and 4 and the plate 15 continue to rise. In this case, a gap is selected between the flange 7 of the rod 6 of the upper crosshead 3, and the rod 6 with the punch 8 and the stop 20 and the sleeve 18 begin to rise along with the cross members 3 and 4. When the extreme upper initial position of the punch 8 is reached, the actuator 2 is turned off. The economic effect in the implementation of the invention is achieved by expanding the technological capabilities and improving the quality of the tablets. Formula of the Invention A device for the manufacture of thin tablets of powder materials, mainly electrodes of chemical current sources, containing upper and lower mobile traverses interconnected by columns, upper punch with a mechanism its height settings, block matrix with placement of a lower punch-ejector into its working cavity. a powder dispenser mounted in a stationary housing, a powder filling height setting mechanism, and a tablet mass measurement mechanism, characterized in that, in order to expand technological capabilities and improve the quality of tablets by increasing the metering accuracy, it is equipped with an intermediate plate with springs and a hinge lever mechanism, the mechanism for adjusting the height of the backfill of the powder material is made in the form of a spring-loaded two-arm lever and an adjustable stop with a drive for its movement, and The pusher pusher is made in the form of a pusher and a rod with a collar and a spring located between them. The intermediate plate is mounted with the ability to interact with the setting mechanism for the height of the upper punch between the stationary body and the upper movable crossbeam, podprgzhinen relative to the rikh and connected with the said body and the upper movable cross-member hinged-lever mechanism, an adjustable stop mounted in a fixed case, and a double-arm lever of the mechanism for adjusting the backfill of the powder mat rial pivotally mounted on a fixed case with the possibility of the interaction of one shoulder with an adjustable stop and the other - the collar of the punch-out rod | Kivatel, FIG. 2 FIG.