JP3628055B2 - Sticking measuring device for tablet press - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to an apparatus for measuring sticking in a tableting machine that compresses tablets.
[0002]
[Prior art]
Many tablet pharmaceuticals, foods, chemicals, and the like are produced by compressing powder raw materials with a compression tableting machine, which is a type of press, to produce tablets.
[0003]
The tableting machine presses the powder raw material injected into the mortar from above and below with an upper punch and lower punch and molds it. However, depending on the type, material, moisture content, etc. of the powder raw material, In some cases, tablet powder that was compression-molded adheres.
[0004]
When such powder adhesion, that is, a sticking phenomenon occurs, the surface of the tablet becomes cloudy or minute irregularities are formed, and the quality and commercial value of the tablet as a molded product are significantly impaired. For example, if the granule in the raw material has a large amount of moisture, the adhesive force between the tablet and the heel surface increases, and the tablet surface is damaged at the moment of separation.
[0005]
Therefore, the sticking phenomenon is determined by taking a measure by determining the surface or ridge surface of the tablet by visual observation or photo observation, or measuring the stick area with a planimeter or the like.
[0006]
[Problems to be solved by the invention]
However, in such a measurement centered on visual observation, the determination of the sticking phenomenon varies due to individual differences among observers, and the reliability of the determination accuracy is low.
[0007]
Further, since the determination is performed not by all products but by punching, there is a problem that the sticking phenomenon cannot be accurately grasped when the adhesive force fluctuates with the passage of time during tableting.
[0008]
An object of the present invention is to quantitatively determine the sticking phenomenon and solve such a problem.
[0009]
[Means for Solving the Problems]
1st invention compresses a powder raw material between an upper punch and a lower punch, the tableting part which shape | molds a tablet, and the tablet pushed out by the said lower punch on this tableting part surface, and adheres to a lower punch In a tableting machine equipped with a scraper that pays off, a replaceable pressure detecting unit in which a gauge plate having a thickness corresponding to the measurement range of the adhesive force between the lower eyelid and the tablet is attached to the contact surface of the scraper with the tablet And means for displaying or recording the detected pressure.
[0010]
According to a second invention, in the first invention, the pressure detection unit is configured such that a thin gauge plate is stretched over a gauge frame, and a strain gauge is attached to the gauge plate.
[0011]
[Action]
In the first invention, when the tablet is removed from the surface by the scraper, the swing-off force is measured by the pressure detection unit. This swing-off force corresponds to the adhesion force between the tablet and the heel surface, and the greater the adhesion force, the greater the detected pressure. Therefore, by measuring this pressure, it is possible to quantitatively grasp the sticking phenomenon due to the adhesion of the tablet. This pressure detection can be performed for each tablet, and even when the adhesive force fluctuates during tableting, a change in the situation can be detected immediately.
[0012]
In the second invention, the load range to be measured can be freely adjusted by the thickness of the gauge plate of the pressure detection unit, and the measurable range can be expanded.
[0013]
【Example】
An embodiment of the present invention will be described with reference to FIGS.
[0014]
FIG. 3 is an overall view of a rotary tableting machine. A plurality of mortars 2 for injecting powder raw materials at equal intervals are provided on the same circumference of a rotating disk 1 that rotates horizontally. An upper punch 3 is disposed above the mortar 2, and a lower punch 4 is also disposed below the mortar 2. The upper and lower ridges 3 and 4 are moved up and down depending on the rotation position of the turntable 1, and therefore, an upper roll 5 and a lower roll 6 are provided at predetermined tableting positions. The upper and lower ridges 3 and 4 are moved to pressurize the powder injected into the die 2 and compress the tablets.
[0015]
Note that the upper punch 3 is maintained in a state of being pulled upward by a mechanism (not shown) except for the tableting position.
[0016]
Reference numeral 10 denotes a scraper that removes the compression-molded tablet M from the turntable 1, and when this position is reached, the lower punch 4 pushes the tablet M in the die 2 up to the surface of the turntable 1 by a cam (not shown) and rotates. The tablet M is dispensed from the die 2 by a scraper 10 located near the surface of the plate 1.
[0017]
Reference numeral 7 denotes a hopper for injecting powder raw material into the die 2, and 8 denotes a feed chute. At this position, the lower punch 4 is lowered, and a predetermined amount of powder raw material is injected into the die 2.
[0018]
As shown in FIGS. 1 and 2, a pressure detection unit 12 is replaceably attached to the scraper 10 that dispenses the tablet M, located on the dispensing surface.
[0019]
The pressure detection unit 12 is fixed to the scraper 10 with screws 14 at both ends of the gauge frame 13. A thin gauge plate 15 is stretched over the gauge frame 13 formed in a bridge state, and both ends thereof are fixed to the gauge frame 13 with screws 16.
[0020]
Two strain gauges 17 are bonded to the gauge plate 15, and the two strain gauges 17 are bonded to the gauge frame 13 in the same manner so as to form a bridge circuit. Apply moisture-proof treatment.
[0021]
A wiring cover 18 is attached to the gauge frame 13 to protect the strain gauge 17.
[0022]
The gauge plate 15 abuts against the tablet M of the mortar 2 from the side and delivers the tablet M. The dispensing load at this time is detected by the strain gauge 17 as the adhesive force between the tablet M and the lower punch 4. As shown in FIG. 4, the output of the strain gauge 17 is input to the controller 20 and displayed and recorded by the display recording unit 21 as shown in FIG. 4.
[0023]
In this embodiment, the pressurizing force at the time of tableting of the upper and lower punches 3 and 4 is detected and input to the controller 20 so that the relationship between the tableting pressure and sticking can be grasped.
[0024]
It is comprised as mentioned above, Next, an effect | action is demonstrated.
[0025]
Along with the rotation of the rotary table 1 of the rotary tableting machine, the powder raw material injected into the die 2 by the feed chute 8 is compression-molded into tablets M by the upper and lower punches 3 and 4 at a predetermined tableting position. . Then, before the scraper 10, the tablet M is pushed out to the surface of the rotating disk 1 by the lower punch 4, contacts the scraper 10, and is removed from the surface of the rotating disk 1. At this time, since the tablet M is wiped off by coming into contact with the gauge plate 15 of the scraper 10, a load corresponding to the adhesive force between the tablet M and the lower collar 4 acts on the gauge plate 15, and the deflection due to this load occurs. The output of the strain gauge 17 changes.
[0026]
The output of the strain gauge 17 is displayed and recorded on the display recording unit 21 via the controller 20.
[0027]
The sticking phenomenon of the tablet M occurs according to the adhesive force with the lower eyelid 4, and when the adhesive force exceeds a predetermined value, the tablet surface may be clouded, minute irregularities, or peeled off. However, the sticking phenomenon can be determined quantitatively and accurately as a pressure value detected by the strain gauge 17 by obtaining the adhesion force when the sticking phenomenon occurs in advance by experiments or the like.
[0028]
In addition, since this determination can be made for all tablets, the tableting conditions change slightly during tableting, and even if no sticking phenomenon occurs at the beginning, the adhesive force increases with time. For example, when it occurs, the occurrence of sticking can be immediately determined based on the detected pressure value.
[0029]
By the way, the adhesive force between the tablet M and the lower arm 4 varies greatly depending on the type of the tablet to be compression-molded, and it varies widely from foods other than pharmaceuticals, chemicals, feeds, etc. Therefore, the absolute value of the measured pressure value Also, for example, it is expected to be in a wide range from a minute value of 0.1 g to 500 g.
[0030]
In order to measure accurately over such a wide pressure range, several types of gauge plates 15 to which the strain gauge 17 is bonded are prepared from those having a very thin thickness, and according to the target measurement pressure range. Replace. When the measurement pressure is small, setting a thin gauge plate 15 causes a large deflection even with a weak load, so that the load can be measured with high accuracy.
[0031]
As described above, when the gauge plate 15 is replaced, or in order to confirm whether the numerical value of the pressure measurement is accurate, a calibration jig as shown in FIG. 6 is used to calibrate the pressure measurement. be able to.
[0032]
The calibration jig 25 includes an adapter 26 for setting the pressure detection unit 12 removed from the scraper 10, and a weight receiving tray 28 on which a calibration reference weight 27 is placed is slidably supported on a support base 29. The support shaft 28 </ b> A of the weight receiving tray 28 is placed on the gauge plate 15 of the pressure detection unit 12.
[0033]
The output of the strain gauge 17 when the calibration reference weight 27 is placed is measured, and it is determined whether or not it is output accurately. In other words, if an output that matches the weight of the weight 27 is displayed, it can be determined that there is no error. If a different numerical value is displayed, the difference with respect to the reference weight becomes an error. Adjust 20 to calibrate to eliminate the difference.
[0034]
In this calibration, linearity of output characteristics can be confirmed by measuring respective outputs using several reference weights, for example, 1 g, 2 g, 5 g, 10 g, 25 g, and 50 g.
[0035]
FIG. 5 shows another embodiment. This is not a rotary type tableting machine but a single type tableting machine, and a scraper that slides from the back of one tableting part. A pressure detection unit 12 is detachably attached to the tip of 10, the scraper 10 is slid after tableting, and the pressure when the tablet M is removed through the pressure detection unit 12 is detected. The scraper 10 reciprocates in a certain range in connection with the tableting operation.
[0036]
Also in this case, the sticking phenomenon due to the adhesive force between the lower eyelid 4 and the tablet M can be quantitatively measured as in the above embodiment.
[0037]
【The invention's effect】
In the first invention, the load when the tablet is removed from the heel surface by the scraper is measured, and this load corresponds to the adhesive force between the tablet and the heel surface, and the detected pressure increases as the adhesive force increases. By measuring the pressure, it is possible to quantitatively grasp the sticking phenomenon due to the adhesion of the tablets, and since this pressure detection can be performed for each tablet, even if the adhesion force fluctuates during tableting, , Immediately grasp the change of the situation, can determine the sticking in real time.
[0038]
In the second invention, the load range to be measured can be freely adjusted according to the thickness of the gauge plate of the pressure detection unit, and accurate measurement can be performed over a wide load range in pharmaceuticals, foods, chemicals, etc. Become.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a main part of an embodiment of the present invention.
FIG. 2 is an exploded perspective view of the pressure detection unit.
FIG. 3 is a schematic perspective view of the tableting machine.
FIG. 4 is a block diagram of the overall configuration in the same manner.
FIG. 5 is a perspective view showing a main part of another embodiment.
FIG. 6 is an explanatory diagram showing calibration of a pressure detection unit.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Rotating disk 2 Mill 3 Upper punch 4 Lower punch 10 Scraper 12 Pressure detection unit 13 Gauge frame 15 Gauge plate 17

Claims (2)

A tableting part that compresses the powder raw material between the upper punch and the lower punch and molds the tablet, and a scraper that pushes the tablet that is pushed out by the lower punch on the surface of the tableting part and adheres to the lower punch. In the tablet press, a replaceable pressure detection unit in which a gauge plate having a thickness corresponding to the measurement range of the adhesive force between the lower punch and the tablet is attached to the contact surface of the scraper with the tablet, and the detected pressure is A sticking measurement device for a tableting machine, comprising means for displaying or recording. Before SL pressure detection unit, stretched thin plate-like gauge plate gauge frame, sticking measuring device tabletting machine according to claim 1, constituted by attaching the strain gauge to gauge plate.

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