Pharmaceutical powder filling system for tablet compression modification research and evaluation method

Abstract

The invention discloses a pharmaceutical powder filling system for tablet compression modification research and an evaluation method, and the filling system comprises an interchangeable static / dynamic scraping system which is used for simulating the working conditions of gravity filling and forced filling; a flexible mold is made of transparent resin, the shape of the flexible mold corresponds to that of a target tablet, and the depth of the flexible mold is adjustable; the invention discloses an image acquisition device and an independent and accurate control system. The evaluation method comprises the following steps: configuring a mold with a specific shape, testing the filling quality at different rotating speeds, calculating the filling efficiency, fitting a curve, and determining a limit filling rotating speed MFS; the feasibility of tablet modification is scientifically evaluated by replacing molds with different shapes, comparing the MFS and estimating the productivity. The problems that existing equipment is not real in simulation, a mold is fixed, parameter regulation and control are extensive, and the process is invisible are solved, and high-fidelity and visual simulation and quantitative evaluation of the industrial tabletting process are achieved.

Description

Technical Field

[0001] This invention relates to the field of pharmaceutical equipment and process research technology, specifically to a system and method for simulating and evaluating powder filling behavior before tablet compression, which is particularly suitable for process feasibility assessment and optimization of traditional Chinese medicine powders, chemical drug powders, etc. in the tablet modification and development stage. Background Technology

[0002] Most existing tablet presses or research equipment employ fixed scraping modes, i.e., only static scraping or only forced scraping, making it difficult to flexibly switch between modes on the same machine and accurately simulate these two significantly different industrial tableting filling scenarios. This results in discrepancies between experimental data and actual production conditions, especially for pharmaceutical powders with varying flowability, leading to poor simulation accuracy. Traditional equipment also has fixed mold shapes and volumes, making it difficult to quickly and easily replace molds of different shapes (e.g., round, elliptical, irregular shapes) or flexibly adjust the mold depth (i.e., filling volume). This severely limits research on tableting modifications for special shapes (e.g., irregularly shaped tablets) or different dosage specifications, requiring the customization of an entire set of molds or equipment for each change, which is not only costly but also time-consuming.

[0003] In powder filling research, the rotational speed of the filling platform (which affects centrifugal force and filling speed) and the stirring speed of the forced filler are two key process parameters. Existing equipment typically struggles to independently control and adjust these two parameters over a wide range with high precision, making it impossible to systematically explore the influence of a single parameter on filling effects (such as density and uniformity), thus hindering process optimization. Furthermore, the opacity of traditional metal molds prevents researchers from directly observing the powder's filling state, fluidization behavior, and potential defects (such as voids and bridging) within the mold, which is detrimental to mechanistic studies and problem diagnosis. Simultaneously, the cumbersome process of replacing equipment components reduces research efficiency.

[0004] In pharmaceutical tablet manufacturing, powder filling is a crucial step before tableting, and the uniformity and density of filling directly affect tablet quality (such as weight variation and hardness). Existing powder filling equipment is mostly designed for standardized tablets, lacking the flexibility to simulate special materials such as traditional Chinese medicine powders, and cannot precisely control filling parameters (such as scraping method and mold shape). Furthermore, traditional equipment struggles to flexibly adjust mold shape and volume, leading to inaccurate evaluation of tablet modification results. Therefore, a system capable of accurately simulating the powder filling process and supporting multiple mold configurations is needed to improve the reliability and efficiency of tablet compression modification research. Summary of the Invention

[0005] To address the shortcomings of the existing technology, this invention provides a pharmaceutical powder filling system and a tablet compression modification evaluation method that achieves accurate simulation of the traditional Chinese medicine powder filling process and scientific evaluation of tablet modification through interchangeable scraping components, an adjustable speed filling platform, and a flexible mold design.

[0006] The technical solution adopted in this invention is:

[0007] A pharmaceutical powder filling system for tablet compression modification research includes: a scraping system, a flexible mold system, and a control system;

[0008] The scraping system can be a dynamic scraper or a static scraper;

[0009] The dynamic scraper is equipped with an agitator driven by a first servo motor;

[0010] The static or dynamic scraper can be selectively fixed to a metal support plate by a combination of locating pins and fastening screws.

[0011] The agitator in the dynamic scraper is connected to the first servo motor via a drive shaft;

[0012] A horizontally rotating metal frustum is driven by a second servo motor in the control system, and at least one sample slot for accommodating a filling mold is provided on its surface.

[0013] A hopper device, located above a dynamic scraper or a static scraper, is used to continuously convey powder during the filling process; a rubber sleeve is provided at the lower end of the hopper device for connecting the dynamic scraper.

[0014] The lower end of the hopper device is provided with an inverted arc-shaped funnel; a filling mold is provided below the arc-shaped funnel;

[0015] A flexible mold system comprising at least two filling molds having different horizontal cross-sectional shapes, the shapes of the filling molds corresponding to the shape of the target tablet to be evaluated, the filling molds being made of a transparent resin material and being removably embedded in the sample slot of the metal frustum;

[0016] The outer contour of the filling mold is a cylinder with a length of 43.00 mm. It contains filling holes of the same shape as the target tablet, such as cylindrical or elliptical. The lower end of the filling hole is connected to a metal spiral push rod mechanism to control the depth of the filling mold.

[0017] An image acquisition device is installed in the cavity below the metal support plate to capture images of powder flow within the filling mold during the filling process.

[0018] A system control display device is located at the front of the device and connected to the control system below; the system control display device is equipped with buttons for starting / stopping the first servo motor and the second servo motor.

[0019] The control system includes a PLC controller for adjusting the rotational speed of the metal frustum and the rotational speed of the agitator wheel in the dynamic scraper.

[0020] Preferably, the metal support plate is positioned above the metal frustum, such that the lower edge of the scraper mounted on it remains in contact with the upper surface of the metal frustum. When the metal frustum rotates, the pharmaceutical powder spread on it is shaped by the scraper and then filled into the filling mold located in the sample slot.

[0021] Preferably, the bottom of the filling mold is provided with a metal spiral push rod mechanism;

[0022] A metal base is embedded in the lower end of the filling mold, and the metal base is connected to the main body of the filling mold by bolts;

[0023] The metal base has a threaded through hole in the center; the threaded through hole and the threaded rod of the helical push rod mechanism form a threaded pair to achieve coaxial connection;

[0024] The metal helical push rod mechanism, from top to bottom, includes a piston silicone pad, a metal piston body, a threaded rod, and a knurled handwheel.

[0025] Preferably, the inner wall of the sample groove of the metal frustum is provided with a positioning structure, and the outer wall of the filling mold is provided with a matching positioning structure to achieve precise circumferential and radial positioning of the mold.

[0026] Preferably, the flexible mold system further includes a transparent observation mold with a rectangular horizontal cross-section, which is larger than the filling mold simulating a real tablet, for magnifying and observing the macroscopic flow behavior of the powder.

[0027] Preferably, the metal circular platform is provided with multiple sample slots, each sample slot having a countersunk hole, and the outer ring of the upper end of the filling mold is adapted to the countersunk hole.

[0028] A method for evaluating tablet compression modification of a pharmaceutical powder filling system for tablet compression modification research includes the following steps:

[0029] S1. Embed the first filling mold corresponding to the shape of the first target tablet into the metal frustum sample slot of the system, and select to install a static scraper or a dynamic scraper;

[0030] S2. In the selected scraping mode, set the process parameters, control the metal frustum to rotate at multiple different speeds, and measure the filling mass of the pharmaceutical powder in the first filling mold after one revolution at each speed.

[0031] S3. Calculate the filling efficiency at each rotational speed based on the filling mass. , = Filling mass m at the current rotational speed / Total filling mass M, and then fit the values ​​to obtain the filling efficiency. - Rotational speed V curve;

[0032] Filling efficiency The fitted curve of the relationship between the rotational speed and the filling speed is a power function. =aX b

[0033] Where a and b are fixed parameters, and X is the filling speed;

[0034] S4. Based on the filling efficiency - The rotational speed V curve determines whether the pharmaceutical powder achieves complete filling under the first filling mold and the current process parameters. The limiting filling speed MFS1 when =1);

[0035] S5. Replace with a second filling mold corresponding to the shape of the second target tablet, and repeat steps S2 to S4 to obtain the corresponding limit filling speed MFS2;

[0036] S6. Compare MFS1 and MFS2, and estimate the theoretical production capacity based on the formula C = N × MFS. Based on the comparison results of the limiting filling speed and theoretical production capacity, evaluate the feasibility of changing the tablet shape from the first shape to the second shape and its impact on production; where N is the simulated number of die holes of the tablet press.

[0037] Preferably, in step S1, when a dynamic scraper is selected, the rotational speed of the agitator is set and adjusted as an independent process parameter; in step S2, the rotational speed of the agitator is systematically changed to obtain multiple sets of filling efficiencies under different forced feeding intensities. - Rotational speed V curve and corresponding MFS.

[0038] Preferably, in step S1, the depth of the first or second filling mold is adjusted by a pusher mechanism at its bottom; in step S2, under the condition of fixing other parameters, the mold depth is systematically changed to obtain multiple sets of filling efficiencies under different sheet weights or filling amounts. - The rotational speed V curve and the corresponding MFS are used for process window optimization.

[0039] Preferably, during the filling process in step S2, images of the powder filling process are simultaneously captured by the image acquisition device to analyze the filling uniformity, flow pattern, and defects, which helps to explain the reasons for the differences in MFS under different molds or process parameters.

[0040] The advantages of this invention over the prior art are:

[0041] This invention discloses a pharmaceutical powder filling system and a method for evaluating tablet compression modification. By constructing a powder filling device that integrates an interchangeable scraper, a precisely adjustable rotation speed filling platform, and a flexible mold system, it successfully achieves high-fidelity simulation and flexible multi-parameter research of the pharmaceutical powder filling process. This solution effectively solves the technical bottlenecks of existing equipment, such as insufficient simulation realism, poor research flexibility, inaccurate parameter control, and lack of process visibility. It significantly improves the efficiency and scientific rigor of tablet compression modification research and provides strong technical support for the process development of tablets with special shapes and new formulations.

[0042] It includes an interchangeable static / forced scraping system, a horizontally adjustable speed metal frustum filling system, and a flexible mold system. Based on the powder filling experiment results of the filling mold morphology, an evaluation method for the modified production performance of powder tableting is derived.

[0043] It enables high-fidelity simulation of the tableting and filling process for specific tablet products; it allows for rapid, quantitative, and visual feasibility assessment of modifications to tablets of any shape; and it provides a multi-dimensional and refined parameter research platform for tableting process optimization. Attached Figure Description

[0044] Figure 1 This is a three-dimensional structural schematic diagram (a) of a pharmaceutical powder filling system for tablet compression modification research according to the present invention.

[0045] Figure 2 This is a three-dimensional structural schematic diagram (II) of a pharmaceutical powder filling system for tablet compression modification research according to the present invention.

[0046] Figure 3 This is a three-dimensional structural schematic diagram (III) of a pharmaceutical powder filling system for tablet compression modification research according to the present invention.

[0047] Figure 4 This is a schematic diagram of the connection structure between the dynamic scraper and the stirring wheel of a pharmaceutical powder filling system for tablet compression modification research according to the present invention;

[0048] Figure 5 This is an exploded structural diagram of the filling mold and metal spiral pusher mechanism of a pharmaceutical powder filling system for tablet compression modification research according to the present invention;

[0049] Figure 6 This is a schematic diagram of the metal spiral pusher mechanism of a pharmaceutical powder filling system for tablet compression modification research according to the present invention;

[0050] Figure 7This is a schematic diagram of the static scraper and metal frustum connection structure of a pharmaceutical powder filling system for tablet compression modification research according to the present invention.

[0051] Figure 8 This is a schematic diagram of the connection structure of the servo motor, drive shaft and scraper of a pharmaceutical powder filling system for tablet compression modification research according to the present invention.

[0052] Figure 9 This is a schematic diagram of the connection structure between the hopper and the dynamic scraper of a pharmaceutical powder filling system for tablet compression modification research according to the present invention.

[0053] Figure 10 This is a schematic diagram of the connection structure between the hopper and the static scraper of a pharmaceutical powder filling system for tablet compression modification research according to the present invention;

[0054] Figure 11 This is a schematic diagram of the mold positioning structure of a pharmaceutical powder filling system for tablet compression modification research according to the present invention;

[0055] Figure 12 This is a schematic diagram of the connection structure between a metal frustum and a motor in a pharmaceutical powder filling system for tablet compression modification research according to the present invention.

[0056] Figure 13 This is a schematic diagram of the connection structure between the dynamic scraper and the metal support plate of a pharmaceutical powder filling system for tablet compression modification research according to the present invention.

[0057] Figure 14 This is a schematic diagram of the static scraper and metal support plate connection structure of a pharmaceutical powder filling system for tablet compression modification research according to the present invention.

[0058] Explanation of symbols for key components in the attached diagram:

[0059] In the diagram: 1. Dynamic scraper; 2. Metal support plate; 3. Metal frustum; 4. Sample chamber

[0060] 5. Filling mold; 6. Metal spiral push rod mechanism; 7. Hopper device; 8. Drive shaft

[0061] 9. First servo motor; 10. Fastening screw; 11. System control display device; 12. First start / stop button; 13. Second start / stop button; 14. Rubber sleeve; 15. Second servo motor; 17. Caster assembly; 18. Agitator wheel; 19. Discharge port; 20. Countersunk hole; 21. Metal base; 22. Threaded through hole; 23. Knurled handwheel; 24. Piston silicone pad; 25. Threaded rod; 26. Metal piston body; 27. Static scraper; 28. Inverted arc-shaped funnel; 29. ​​Drive belt. Detailed Implementation

[0062] The present invention will now be described in detail with reference to the accompanying drawings and embodiments:

[0063] Working process and working principle of dynamic scraper:

[0064] The dynamic scraper employs an active rotation filling method, its core being a scraper driven by a transmission shaft. During operation, the first servo motor 9 drives the transmission shaft 8, causing the radially distributed agitator wheels 18 at the bottom to rotate continuously. During rotation, the agitator wheels 18 utilize centrifugal force to evenly push the powder from the center outwards, actively and forcibly filling the passing filling molds 5. This active pushing mechanism is particularly suitable for powders with poor flowability and high viscosity, ensuring sufficient and uniform filling. As the tablet press turntable rotates, the rotating scraper continuously fills each successively passing filling mold. By adjusting the rotation speed, the filling amount and density can be precisely controlled, making it particularly suitable for the production needs of high-speed tablet presses.

[0065] Working process and working principle of static scraper:

[0066] The static scraper employs a passive leveling filling method. Its structural feature is that the entire device is fixed to a metal support plate 2, remaining stationary. Filling is completed by the metal frustum 3 driving the filling mold relative to the static scraper. During operation, the powder is stored in the upper hopper device 7, with an inverted arc-shaped funnel 28 at its lower end. When the metal frustum 3 drives the filling mold 5 past the static scraper, the powder falls naturally into the filling mold 5 under its own gravity through the inverted arc-shaped funnel 28. The static scraper levels the powder, removing excess powder and ensuring a uniform filling amount in the filling mold 5. This gravity filling method is simple and reliable, requiring no additional power drive system, resulting in low maintenance costs and minimal mechanical damage to the powder, thus better preserving its original properties. The static scraper is particularly suitable for powders with good flowability. The filling effect can be optimized by adjusting the hopper height. It is widely used in low-to-medium speed tablet production, offering advantages such as energy saving, environmental protection, and ease of operation and maintenance.

[0067] The dynamic scraper is configured with an independent motor driving the agitator wheel:

[0068] The agitator wheel 18 is configured with an independent top-mounted drive. Specifically, a small, independent motor is installed above the hopper of the dynamic scraper 1. This motor is connected to the drive shaft 8 via a transmission belt, and the drive shaft 8 is directly connected to the agitator wheel 18. This motor drive is independent of the main filling drive system, allowing for independent control of the rotation speed and direction of the agitator wheel 18. This enables continuous agitation of the powder within the scraper 1 and prevents bridging. The advantage of this independent drive design is that the agitation intensity can be adjusted according to the flow characteristics of different powders, ensuring that the powder remains loose and uniform, and preventing stratification, clumping, or bridging due to prolonged settling time.

[0069] The connection between the dynamic scraper and the agitator wheel, and their connection with other components:

[0070] The dynamic scraper 1 and the agitator wheel 18 are connected via an integrated housing. The agitator wheel 18 and the scraper cavity are connected by a central bearing support. Specifically, sealed bearing assemblies are installed at both ends of the central shaft of the agitator wheel, and the bearing seats are directly fixed to the upper cover plate of the scraper cavity. These are fastened with bolts to form a stable support system, ensuring the concentricity and stability of the wheel during high-speed rotation. The connection between the agitator wheel 18 and other components includes: the upper part is connected to an independent motor via a transmission pump 8 for power input; the middle part is fixed to the hopper housing via a bearing seat to ensure stability during rotation; the lower stirring blades are suspended in the powder layer, maintaining an appropriate gap with the bottom outlet to avoid interfering with the rotating scraper system below. The entire dynamic scraper 1 is bolted to a metal support plate 2 for easy disassembly, cleaning, and maintenance.

[0071] Precise circumferential and radial positioning of the mold: The upper part of the sample groove 4 of the metal frustum 3 is provided with a cylindrical countersunk hole 20, and the upper outer ring of the filling mold is designed with a stepped flange that matches it. The outer diameter of the flange and the inner diameter of the countersunk hole are precisely matched, and the radial clearance is controlled within 0.01-0.05 mm. The mold automatically centers when inserted, achieving radial positioning and preventing radial movement during high-speed rotation. The bottom surface of the flange and the stepped surface of the countersunk hole fit tightly to form an axial limit, ensuring the consistency of the mold height.

[0072] The choice between static and dynamic scrapers depends primarily on the physical properties of the drug powder, production process requirements, and equipment cost considerations. When the drug powder has good flowability (angle of repose ≤ 35°), uniform particle size, and is not prone to bridging or clumping, a static scraper is preferred. It relies on gravity for natural filling, has a simple structure, low maintenance costs, and low energy consumption, making it suitable for low-to-medium speed tableting (30-60 tablets / minute) and scenarios with relatively relaxed requirements for tablet weight variation. When the drug powder has poor flowability (angle of repose > 40°), high viscosity, is prone to arching, or has a small particle size, a dynamic scraper is required. It uses an independent servo motor to drive the agitator 18 in the dynamic scraper 1 to forcibly push the drug powder, ensuring uniform filling of the filling mold. The rotation speed can be precisely adjusted according to the drug powder characteristics, making it suitable for high-speed tableting (60-200 tablets / minute) and scenarios with strict tablet weight accuracy requirements.

[0073] Furthermore, static scrapers are suitable for small and medium-sized enterprises with limited budgets and weak maintenance capabilities, as well as for the research and development testing phase, while dynamic scrapers are suitable for large pharmaceutical companies with large-scale production, multi-product switching, and high levels of automation.

[0074] Appendix Figure 1-14 It is known that a pharmaceutical powder filling system for tablet compression modification research includes: a scraping system, a flexible mold system, and a control system;

[0075] The scraping system is either a dynamic scraper 1 or a static scraper 27;

[0076] The dynamic scraper 1 is equipped with an agitator 18 driven by a first servo motor 9;

[0077] The static scraper 1 or the dynamic scraper 27 can be selectively fixed to a metal support plate 2 by a combination of positioning pins and fastening screws 10.

[0078] The agitator wheel 18 in the dynamic scraper 1 is connected to the first servo motor 9 via a transmission shaft 8;

[0079] The horizontally rotating metal frustum 3 is driven by the second servo motor 15 in the control system, and at least one sample slot 4 for accommodating the filling mold is provided on its surface.

[0080] The hopper device 7 is located above the dynamic scraper 1 or the static scraper 27 and is used to continuously convey powder during the filling process; the lower end of the hopper device 7 is provided with a rubber sleeve 14 for connecting the dynamic scraper 1.

[0081] The lower end of the hopper device 7 is provided with an inverted arc-shaped funnel 28; a filling mold 5 is provided below the arc-shaped funnel 28;

[0082] A flexible mold system includes at least two filling molds 5 with different horizontal cross-sectional shapes, the shapes of the filling molds 5 corresponding to the shape of the target tablet to be evaluated, the filling molds 5 being made of transparent resin material and being detachably embedded in the sample slot 4 of the metal frustum;

[0083] The outer contour of the filling mold 5 is a cylinder with a length of 43.00 mm. It has a filling hole with the same shape as the target tablet, such as a cylinder or an ellipse. The lower end of the filling hole is connected to a metal spiral push rod mechanism to control the depth of the filling mold.

[0084] An image acquisition device is installed in the cavity below the metal support plate 2 to capture images of powder flow within the filling mold 5 during the filling process.

[0085] The system control display device 11 is located at the front of the device and is connected to the control system below; the system control display device 11 is equipped with a button 13 for starting / stopping the first servo motor 9 and a button 12 for starting / stopping the second servo motor 15;

[0086] The control system includes a PLC controller for adjusting the rotational speed of the metal frustum and the rotational speed of the agitator wheel in the dynamic scraper.

[0087] Preferably, the metal support plate 2 is positioned above the metal frustum 3, such that the lower edge of the scraper mounted on it is in contact with the upper surface of the metal frustum. When the metal frustum 3 rotates, the pharmaceutical powder placed on it is sorted by the scraper and then filled into the filling mold 5 located in the sample slot 4.

[0088] Preferably, the bottom of the filling mold is provided with an adjustable metal spiral push rod mechanism 6 for continuously changing the depth of the mold cavity.

[0089] A metal base 21 is embedded in the lower end of the filling mold 5, and the metal base is connected to the filling mold body by bolts;

[0090] The metal base has a threaded through hole 22 at its center; the threaded through hole 22 and the threaded rod 25 of the spiral push rod mechanism 6 form a threaded pair to achieve coaxial connection;

[0091] The metal spiral push rod mechanism includes, from top to bottom, a piston silicone pad 24 (for sealing the metal piston to prevent powder leakage); a metal piston body 26 (used as the bottom structure for contact with powder in the filling mold); a threaded rod 25 (used as a spiral push rod for adjusting the depth of the filling mold); and a knurled handwheel 23 (used as a hand-turning structure for adjusting the depth).

[0092] Bolts are positioned and tightened by passing through pre-drilled holes. By rotating the knurled handwheel at the bottom of the push rod, the rotational motion is converted into axial linear motion using the principle of threaded transmission, thereby continuously adjusting the effective depth of the mold cavity and achieving precise control of the filling volume.

[0093] The static scraper is equipped with a wear-resistant wool sealing strip at its lower edge, and the dynamic scraper is equipped with a polytetrafluoroethylene arc-shaped seal at its bottom to prevent powder leakage.

[0094] Preferably, the inner wall of the sample groove of the metal frustum 3 is provided with a positioning structure, and the outer wall of the filling mold is provided with a matching positioning structure to achieve precise circumferential and radial positioning of the mold.

[0095] Preferably, the flexible mold system further includes a transparent observation mold with a rectangular horizontal cross-section, which is larger than the filling mold 5 that simulates a real tablet, for magnifying and observing the macroscopic flow behavior of the powder.

[0096] Preferably, the metal frustum 3 is provided with multiple sample slots 4, each sample slot 4 having a countersunk hole 20, and the outer ring of the upper end of the filling mold 5 is adapted to the countersunk hole.

[0097] A method for evaluating tablet compression modification of a pharmaceutical powder filling system for tablet compression modification research includes the following steps:

[0098] S1. Embed the first filling mold corresponding to the shape of the first target tablet into the metal frustum sample slot of the system, and select to install a static scraper or a dynamic scraper;

[0099] S2. In the selected scraping mode, set the process parameters, control the metal frustum to rotate at multiple different speeds, and measure the filling mass of the pharmaceutical powder in the first filling mold after one revolution at each speed.

[0100] The servo motor is directly connected to the metal frustum spindle via a flexible coupling. The servo motor's built-in high-resolution encoder provides real-time speed feedback, forming a closed-loop control circuit to ensure speed accuracy within ±0.1 rpm. Different operating speeds can be preset via a touchscreen interface, and speed switching is completed within 0.2-0.5 seconds after a command is issued by the PLC controller. S3. Calculate the filling efficiency at each speed based on the stated filling quality. , = Filling mass m at the current rotational speed / Total filling mass M, and then fit the values ​​to obtain the filling efficiency. - Rotational speed V curve;

[0101] Filling efficiency The fitted curve of the relationship between the rotational speed and the filling speed is a power function. =aX b

[0102] Where a and b are fixed parameters, and X is the filling speed;

[0103] For a certain type of powder, the fitted - The rotational speed V curve is unique. The mathematical function relationship can be obtained from the fitted curve, and the parameters a and b can be obtained.

[0104] S4. Based on the filling efficiency - The rotational speed V curve determines whether the pharmaceutical powder achieves complete filling under the first filling mold and the current process parameters. The limiting filling speed MFS1 when =1);

[0105] S5. Replace with a second filling mold corresponding to the shape of the second target tablet, and repeat steps S2 to S4 to obtain the corresponding limit filling speed MFS2;

[0106] S6. Compare MFS1 and MFS2, and estimate the theoretical production capacity based on the formula C = N × MFS. Based on the comparison results of the limiting filling speed and theoretical production capacity, evaluate the feasibility of changing the tablet shape from the first shape to the second shape and its impact on production; where N is the simulated number of die holes of the tablet press.

[0107] Preferably, in step S1, when a dynamic scraper is selected, the rotational speed of the agitator is set and adjusted as an independent process parameter; in step S2, the rotational speed of the agitator is systematically changed to obtain multiple sets of filling efficiencies under different forced feeding intensities. - Rotational speed V curve and corresponding MFS.

[0108] Preferably, in step S1, the depth of the first filling mold or the second filling mold is adjusted by the push rod mechanism at its bottom; in step S2, under the condition of fixing other parameters, the mold depth is systematically changed to obtain multiple sets of filling efficiency η-speed V curves and corresponding MFS under different sheet weights or filling amounts, for process window optimization.

[0109] Preferably, during the filling process in step S2, the image acquisition device simultaneously captures images of the powder filling process, analyzes the filling uniformity, flow pattern and defects, and helps to explain the reasons for the differences in MFS under different molds or process parameters.

[0110] This invention discloses a pharmaceutical powder filling system and a method for evaluating tablet compression modification. By constructing a powder filling device that integrates an interchangeable scraper, a precisely adjustable rotation speed filling platform, and a flexible mold system, this invention successfully achieves high-fidelity simulation and flexible multi-parameter research of the pharmaceutical powder filling process. This solution effectively solves the technical bottlenecks of existing equipment, such as insufficient simulation realism, poor research flexibility, inaccurate parameter control, and lack of process visibility. It significantly improves the efficiency and scientific rigor of tablet compression modification research, providing strong technical support for the process development of tablets with special shapes and new formulations.

[0111] It includes an interchangeable static / forced scraping system, a horizontally adjustable speed metal frustum filling system, and a flexible mold system. Based on the powder filling experiment results of the filling mold morphology, an evaluation method for the modified production performance of powder tableting is derived.

[0112] It enables high-fidelity simulation of the tableting and filling process for specific tablet products; it allows for rapid, quantitative, and visual feasibility assessment of modifications to tablets of any shape; and it provides a multi-dimensional and refined parameter research platform for tableting process optimization.

[0113] Interchangeable static / forced scraping systems:

[0114] The interchangeable static / forced scraping system consists of a static scraper 1 and a dynamic scraper 2, which are fixed and interchangeable via screw holes designed into a metal support plate. Sufficient cavity clearance is left below the metal support plate to allow for microscopic observation of the powder flow state using a high-speed camera during powder filling tests. The dynamic scraper contains two impellers that forcibly agitate the powder being filled, making powder flow and filling easier. The impellers are individually controlled by an upper impeller motor, with a speed range of 0-100 rpm.

[0115] With interchangeable static / dynamic scrapers, pre-calibration of powder conversion tableting equipment can be achieved on a single instrument, which has practical significance for production line updates and equipment replacement.

[0116] The powder filling device includes a metal disc mold with a radius of 160 mm, such as... Figure 3 ;

[0117] The metal disc mold has four sample slots with an inner diameter of 22.02 mm on its edge. In addition, there is a square sample slot with a size of 29.10 x 29.10 mm next to the circular sample slots.

[0118] The sample slot has a concave structure, which facilitates the placement of the material receiving and filling mold;

[0119] The scraper is connected above the metal disc mold.

[0120] To prevent wear between the scraper and the metal disc during operation, an arc-shaped resin wear connector is installed at the point where the scraper contacts the metal disc below.

[0121] The rotation of the metal disc is controlled by a servo motor in the motion control system connected to the drive shaft below it, with a speed range of 0-50 rpm.

[0122] The connection mechanism between the two scrapers and the metal support plate is as follows: The metal support plate has horizontally symmetrically distributed positioning holes, with two positioning holes on each side, used to achieve assembly connection between the two scrapers and the metal support plate, and quick switching between scraper types. The connection method adopts a combination positioning mechanism of positioning pins and fastening screws. Precise positioning is achieved through positioning pins, and reliable fixing is achieved with fastening screws, thus ensuring high-precision repeatable positioning of the scraper every time it is installed or replaced.

[0123] Drive mechanism of the dynamic scraper rotor: The rotor speed (i.e., the material feeding speed) of the dynamic scraper can be independently controlled. Its transmission system is structured as follows: the rotor shaft is connected to a gear via a coupling, and the gear is connected to the output end of a servo motor at the top of the filling system via a synchronous belt. This configuration allows for precise and independent control of the rotor speed by the servo motor, thus providing reliable experimental conditions for studying the key process parameter of forced material feeding speed during material filling.

[0124] By quickly switching between static and dynamic scrapers, the filling system can flexibly switch between different scraping modes. This system can accurately simulate two typical filling conditions in industrial tablet presses: (1) gravity natural filling under static scraper mode, where the material relies on its own gravity and flowability to fill the die holes; (2) mechanical forced filling under dynamic scraper mode, where the rotating wheel applies additional mechanical thrust to the material to enhance the filling effect. This dual-mode configuration enables the system to comprehensively evaluate the differences in performance of key physical properties such as powder flowability, filling uniformity, and filling density under different tableting process conditions. By comparing and analyzing process indicators such as tablet weight difference (RSD%) and filling rate under gravity filling and forced filling modes, it provides quantitative experimental data support for formulation optimization, process route selection, and equipment selection, thereby improving process development efficiency and reducing the risk of industrial scale-up.

[0125] The fixing and sealing mechanism of flexible mold, scraper and metal disc:

[0126] The metal disk has positioning edges that match the outline of the flexible mold. The flexible mold is embedded into the sample slot via an interference fit. After installation, its upper surface forms the same reference plane as the metal disk, achieving a peripheral seal. This fit effectively prevents radial displacement and axial runout of the flexible mold during system operation, while also preventing powder leakage from the assembly gaps.

[0127] Static scraper: A wear-resistant wool sealing strip is pasted at the interface between it and the metal disc. The flexibility and resilience of the wool fibers are used to achieve a tight seal, effectively preventing fine powder from escaping from the scraper gap.

[0128] Dynamic scraper: It features a replaceable polytetrafluoroethylene (PTFE) arc-shaped seal at its bottom. The arc profile of this seal precisely matches the curved surface of the scraper's bottom, maintaining a dynamic fit during the rotation of the roller. PTFE material offers excellent wear resistance, a low coefficient of friction, and chemical inertness, while also being cost-effective and readily available.

[0129] The aforementioned sealing configuration ensures the airtightness of the powder filling process under different scraping modes, preventing errors in filling quality measurement caused by material loss and improving the reliability and repeatability of experimental data. Simultaneously, the sealing components are made of conventional industrial materials, facilitating maintenance and replacement and reducing system operating costs.

[0130] Visualization and Observation Function of the Square Filling Mold: The flexible mold system is equipped with a square transparent observation mold with dimensions of 29.1 mm × 29.1 mm × 30 mm, serving as a visualization research tool and auxiliary evaluation tool for standard industrial filling experiments. Given the small orifice size (typical diameter 5-12 mm) commonly used in industrial tablet production, even when made of transparent materials, the limited spatial scale makes it difficult to clearly observe the dynamic flow behavior during powder filling. This observation mold, by magnifying the filling space size and combining it with the application of transparent materials, along with a high-speed camera system (frame rate ≥ 1000 fps) or a digital imaging device with high-speed slow-motion capability, can capture high-temporal-resolution image sequences of the powder filling process. This method enables real-time visualization monitoring and identification of typical flow patterns such as gravity-driven free flow, funnel flow / overall flow patterns, bridging phenomena, mouse-hole effects, and stratified flow. This provides a visual basis for adjusting process parameters such as scraping speed and filling time, evaluating the effectiveness of formulation improvement measures, and diagnosing the root causes of quality problems such as uneven filling and tablet weight fluctuations. It transforms the powder flow behavior that is difficult to observe at the microscale into recordable and analyzable experimental data, providing a powerful research tool for the scientific development of tableting processes.

[0131] Scraping parameters are used as variables:

[0132] A certain mass of digestive tablet granules was added to the loading tank of the powder filling system. The static and dynamic scraper rollers were rotated at speeds of 10, 30, 60, and 90 rpm. Filling speeds of 1 rpm, 8 rpm, 16 rpm, 24 rpm, 32 rpm, 40 rpm, 48 rpm, 56 rpm, and 64 rpm were selected for filling experiments. The mass of powder m in the receiving cup of the metal disc filling system was recorded for each experiment (one rotation of the mold during equipment operation constitutes one experiment). When filling at a speed of 1 rpm, all sample powders were completely filled (i.e., the sample powder filled the filling mold cavity). Therefore, the filling mass at a filling speed of 1 rpm was defined as the completely filled mass M. According to the formula... The filling efficiency at different speeds was calculated (see Table 1). A function model was fitted with the filling efficiency of the sample powder as the vertical axis and the filling speed as the horizontal axis. When =1, calculate the corresponding filling speed, which is the maximum fill speed (MFS) of the sample powder (see Table 2).

[0133] Table 1. Filling efficiency % of sample powder at different filling speeds (n=3)

[0134] Rotor speed 1 rmp 8 rmp 16 rmp 24 rmp 32 rmp 40 rmp 48 rmp 56 rmp 64 rmp static 1.00 0.94±0.01 0.77±0.01 0.59±0.01 0.47±0.02 0.38±0.00 0.34±0.01 0.14±0.01 - 10rmp 1.00 1.00±0.00 0.97±0.00 0.56±0.00 0.54±0.01 0.44±0.02 0.31±0.02 0.18±0.00 - 30rmp 1.00 1.00±0.01 1.00±0.02 0.85±0.02 0.38±0.01 0.31±0.01 0.25±0.01 0.22±0.01 - 60rmp 1.00 1.00±0.01 1.00±0.02 1.00±0.02 1.00±0.01 0.80±0.03 0.65±0.03 0.46±0.03 0.45±0.01 90rmp 1.00 1.00±0.01 1.00±0.04 0.80±0.02 0.58±0.03 0.56±0.02 0.32±0.02 0.25±0.01 -

[0135] Table 2. Parameters of the fitting equation for sample powder filling efficiency and filling speed

[0136] Rotor speed Parameter a Parameter b <![CDATA[R 2 ]]> Maximum fill speed MFS (rmp) static 15.91184 -0.59978 0.88 8.45 10rmp 227.39271 -1.03187 0.94 16.14 30rmp 48240.03093 -1.92847 0.94 22.50 60rmp 3846.49569 -1.36364 0.96 35.72 90rmp 654.34546 -1.17183 0.91 24.47

[0137] System analysis based on experimental data shows that the rotor speed is a key process parameter that determines filling performance and production capacity.

[0138] The 60rpm dynamic scraper wheel exhibits significant performance advantages, with a maximum filling speed (MFS) of 35.72rpm, which is 4.2 times that of the static scraper (8.45rpm). In the full-speed range (8-64rpm) filling test, the 60rpm wheel can maintain complete filling at a filling speed of 32rpm. =1.00±0.01), maintaining a high efficiency of 0.80±0.03 at 40rpm, and even reaching a filling efficiency of 0.45±0.01 at an ultra-high speed of 64rpm, far exceeding other conditions. In contrast, the efficiency of static scraping drops to 0.77 at 16rpm and only 0.14 at 56rpm; the MFS of the 10rpm and 90rpm impellers are 16.14 and 24.47rpm respectively, with performance between static and 60rpm; while the 30rpm impeller performs well at a filling speed of 24rpm ( =0.85), but suddenly drops to 0.38 at 32 rpm, posing a risk of a narrow process window. In terms of capacity, a 60 rpm rotary drum combined with a filling speed of 24-40 rpm can achieve a capacity of 1,080-1,800 tablets / min (assuming a 45-hole mold), which is 5 times that of static scraping (360 tablets / min), achieving optimal conditions for high capacity. Therefore, it is recommended to use a 60 rpm rotary drum speed as the standard process configuration, and to achieve flexible tablet weight adjustment (0.40-0.50g) by adjusting the filling speed (24-40 rpm). This satisfies both quality-priority scenarios (≤32 rpm, η≥0.95) and capacity-priority needs (40 rpm, η≥0.80), providing a scientific process design space and capacity optimization path for the industrial production of digestive tablets and similar solid dosage forms.

[0139] Mold depth (volume) as a variable:

[0140] A certain mass of digestive tablet granules was added to the loading trough of the powder filling system. The scraper wheel of the dynamic scraper rotated at 30 rpm, and the mold depths were 15, 20, and 40 mm. Filling speeds of 1 rpm, 8 rpm, 16 rpm, 24 rpm, 32 rpm, 40 rpm, 48 rpm, 56 rpm, and 64 rpm were selected for filling experiments. The mass of powder m in the receiving cup of the metal disc filling system was recorded for each experiment (one rotation of the mold during equipment operation constitutes one experiment). When filling at a speed of 1 rpm, all sample powders were completely filled (i.e., the sample powder filled the filling mold cavity). Therefore, the filling mass at a filling speed of 1 rpm was defined as the completely filled mass M. According to the formula... The filling efficiency at different speeds was calculated (see Table 3). A function model was fitted with the filling efficiency of the sample powder as the vertical axis and the filling speed as the horizontal axis. When the value is 1, calculate the corresponding filling speed, which is the maximum fill speed (MFS) of the sample powder (see Table 4).

[0141] Table 3. Filling efficiency % of sample powder at different filling speeds (n=3)

[0142] mold depth 1 rmp 8 rmp 16 rmp 24 rmp 32 rmp 40 rmp 48 rmp 56 rmp 64 rmp 15mm 1.00 1.00±0.01 1.00±0.02 1.00±0.01 0.89±0.02 0.77±0.00 0.68±0.01 0.51±0.01 0.44±0.03 20mm 1.00 1.00±0.01 1.00±0.03 1.00±0.02 0.93±0.01 0.90±0.02 0.75±0.02 0.60±0.00 0.48±0.01 40mm 1.00 1.00±0.01 1.00±0.02 0.63±0.02 0.43±0.00 0.33±0.01 0.32±0.02 0.30±0.01 0.29±0.02

[0143] Table 4. Parameters of the fitting equation for sample powder filling efficiency and filling speed

[0144] mold depth Parameter a Parameter b <![CDATA[R 2 ]]> Maximum fill speed MFS (rmp) 15mm 168.04607 -0.85699 0.88 30.72 20mm 10.44741 -0.50221 0.93 33.20 40mm 96.4699 -0.89124 0.92 14.14

[0145] Experimental data shows that a depth of 20mm achieved the highest maximum fill speed (MFS = 33.20rpm); in the full speed range test, 20mm maintained perfect fill in the low-speed range (1-24rpm). =1.00±0.02), maintaining high efficiency in the medium-to-high speed range (32-56 rpm). =0.93→0.90→0.75→0.60), exhibiting a smooth and continuous decay curve with no risk of abrupt changes. In contrast, the 15mm shallow orifice, while achieving complete filling in the low-speed range (≤24rpm), =1.00) and MFS reached 30.72rpm, close to the 20mm level, but the efficiency dropped rapidly from 32rpm (0.89→0.77→0.68), dropping to 0.51 and 0.44 in the high-speed range (56-64rpm). This is because the shallow holes resulted in too short a contact time between the powder and the mold, and insufficient filling at high speeds; the 40mm deep holes showed the complete opposite characteristics—although they performed excellently in the extremely low-speed range (≤16rpm) ( =1.00) Benefited from gravity assistance and sufficient filling time, but suddenly collapsed to 0.63 at 24 rpm, and further deteriorated to 0.43 at 32 rpm. Subsequently, it stabilized at an extremely low level (0.33-0.29) in the high-speed range of 40-64 rpm, resulting in an MFS of only 14.14 rpm (only 43% of 20mm). This "excellent at low speed, collapse at medium and high speed" pattern is due to the superposition of multiple unfavorable factors such as the centrifugal force expulsion effect of deep holes at higher speeds, airflow obstruction in the holes (deep holes form a piston-cylinder structure, which leads to increased air pressure and hinders the falling of powder), and insufficient compaction of powder stratification. Regarding capacity impact, assuming a 45-hole die and corresponding full fill mass (15mm: 0.30g, 20mm: 0.40g, 40mm: 0.80g), the theoretical capacity for a 20mm depth at practical MFS (33.20rpm) can reach 1,496 pieces / min, significantly better than the capacity for a 15mm depth at 32rpm (1,204 pieces / min). =0.89) and 40mm are limited by the maximum capacity of low MFS (only 636 wafers / min); although 40mm has a larger single wafer quality and can achieve higher quality capacity (g / min), its extremely low MFS severely limits the space for speed increase, and it completely loses its competitiveness in scenarios that require high wafer number capacity.

[0146] Whether the servo motor driving the filling drum and the motor driving the scraper are controlled by the same programmable logic controller (PLC) or industrial computer, and whether their speeds can be independently set and precisely synchronized, is the foundation for achieving precise parameter control.

[0147] Control System Architecture and Synchronization Mechanism: This filling system adopts a centralized control architecture. The servo motors driving the filling drum and the scraper wheel are both managed by the same programmable logic controller (PLC). At the software level, the two motor control programs employ a multi-threaded parallel processing mechanism, each running in an independent program thread with its own memory address space and control logic, ensuring no interference. This architecture allows for independent setting and adjustment of the rotational speeds of the two drive systems, while also enabling high-precision speed synchronization control via the PLC's real-time communication bus. Specifically, operators can independently set the filling drum speed (simulating the tablet press turntable speed) and the scraper wheel speed (controlling the forced feeding intensity) according to process requirements. The PLC achieves precise speed ratio control of both through internal timers and encoder feedback signals, with a synchronization accuracy of ±0.1%. This centralized control, independent adjustment, and precise synchronization control mode provides a reliable hardware and software foundation for the precise control and optimization of key process parameters such as speed ratio, filling time, and feeding intensity during the filling process. It is the core technological guarantee for achieving parameterized research and process reproducibility in the filling process.

[0148] Data acquisition and processing: The filling mass m is measured by manual weighing after the machine is stopped. The data is collected online by adding a weight sensor at the bottom of the mold.

[0149] Irregularly shaped tablets refer to tablets compressed into special non-circular shapes (such as digestive tablets, which are triangular in shape), while regular tablets are usually round tablets. The main difference between the two lies in their appearance: irregularly shaped tablets are made into various irregular shapes using special mold designs, which have advantages such as easier identification, easier swallowing, and prevention of confusion. They are often used for brand identification or to distinguish different dosages. Regular round tablets are the most traditional and common tablet form, and their manufacturing process is relatively simple. In fact, whether round or irregularly shaped, they are the same in terms of preparation principle, quality requirements, and administration method. They are all solid dosage forms made by mixing and compressing drugs and excipients. The only difference is the shape of the die used during tablet compression.

[0150] 1. Evaluation of the modified digestive tablets

[0151] Take the following medicinal herbs: Codonopsis pilosula, dried tangerine peel, hawthorn, and roasted malt. Weigh each herb according to the prescription for Jianwei Xiaoshi Tablets in the 2025 edition (Part I) of the Chinese Pharmacopoeia. Add water and decoct, filter, and concentrate the filtrate into a clear extract. Spray dry the obtained clear extract to obtain an extract powder. Mix the above extract powder with an appropriate amount of excipients, use dextrin aqueous solution as a binder, and perform fluidized bed granulation to obtain the granules of Jianwei Xiaoshi Tablets before tableting.

[0152] A certain mass of digestive tablet granules was added to the loading trough of the powder filling system. The rotation speed of the scraper wheel in the dynamic scraper was fixed at 30 rpm. Filling speeds of 1 rpm, 8 rpm, 16 rpm, 24 rpm, 32 rpm, 40 rpm, 48 rpm, and 56 rpm were selected to conduct filling experiments on the sample powder. The mass of powder in the receiving cup of the metal disc filling system was recorded for each experiment (m) (one rotation of the mold during equipment operation constitutes one experiment). Whenever filling was performed at a speed of 1 rpm, all sample powders were completely filled (i.e., the sample powder filled the cavity of the filling mold). Therefore, the filling mass at a filling speed of 1 rpm was defined as the completely filled mass M. According to the formula... The filling efficiency at different speeds was calculated (see Table 5). A function model was fitted with the filling efficiency of the sample powder as the vertical axis and its filling speed as the horizontal axis. When the value is 1, the corresponding filling speed is calculated, which is the maximum fill speed (MFS) of the sample powder (see Table 6). MFS is directly related to the actual tablet production capacity, as shown in the formula: Using MFS as the evaluation index, by changing different filling molds (such as round, elliptical, and irregular shapes), the differences in filling performance of sample powder in different molds can be systematically examined, thereby assessing the feasibility of changing the tablet shape from the perspective of tablet production capacity.

[0153] Table 5. Filling efficiency % of sample powder at different filling speeds (n=3)

[0154] mold 1 rmp 8 rmp 16 rmp 24 rmp 32 rmp 40 rmp 48 rmp 56 rmp round 1.00 1.00±0.01 1.00±0.01 0.84±0.00 0.37±0.01 0.30±0.00 0.24±0.01 0.14±0.01 oval 1.00 1.00±0.00 0.74±0.00 0.42±0.00 0.35±0.01 0.33±0.00 0.30±0.02 0.24±0.00 Alien 1.00 1.00±0.00 0.90±0.02 0.75±0.00 0.48±0.01 0.35±0.01 0.25±0.02 -

[0155] Table 6. Parameters of the fitting equation for sample powder filling efficiency and filling speed

[0156] sample Parameter a Parameter b <![CDATA[R 2 ]]> Maximum fill speed MFS (rmp) round 669.76 -2.11 0.96 22.30 oval 7.93 -0.87 0.92 10.80 Alien 15.81 -1.01 0.93 15.38

[0157] The results show that the fitting curve of the relationship between the sample powder filling efficiency and the filling speed (see Table 2) is a power function. , where a and b are fixed parameters, and X is the filling speed.

[0158] For the same sample powder, using the same filling instrument for pre-tablet filling experiments, the limiting filling speed of tablets compressed with different tablet molds (filling molds) differed significantly. For digestive tablets, round tablets yielded the highest production capacity, 2.06 times that of elliptical tablets and 1.45 times that of irregularly shaped tablets. Irregularly shaped tablets were the second highest, yielding 1.42 times the production capacity of elliptical tablets. Furthermore, as... Figure 9 As shown, at the same filling speed, the filling volume of different filling dies is different, V (round) > V (irregular) > V (elliptical). This result also verifies the results in Table 1 and Table 2.

[0159] 2. Evaluation of modified Panax notoginseng extract

[0160] Take Panax notoginseng slices, crush them, add water and decoct, filter, and concentrate the filtrate into a clear extract. The obtained clear extract is spray-dried to obtain Panax notoginseng extract powder.

[0161] A certain mass of Panax notoginseng extract was added to the loading tank of the powder filling system. The rotation speed of the scraper wheel in the dynamic scraper was fixed at 30 rpm. Filling speeds of 1 rpm, 8 rpm, 16 rpm, 24 rpm, 32 rpm, 40 rpm, 48 rpm, and 56 rpm were selected to conduct filling experiments on the sample powder. The mass of powder m in the receiving cup of the metal disc filling system was recorded for each experiment (one rotation of the mold during equipment operation constitutes one experiment). Whenever the filling speed was 1 rpm, all sample powders could be completely filled (i.e., the sample powder filled the cavity of the filling mold). Therefore, the filling mass at a filling speed of 1 rpm was defined as the completely filled mass M. According to the formula... The filling efficiency at different speeds was calculated (see Table 7). A function model was fitted with the filling efficiency of the sample powder as the vertical axis and the filling speed as the horizontal axis. When =1, calculate the corresponding filling speed, which is the maximum fill speed (MFS) of the sample powder (see Table 8).

[0162] Table 7. Filling efficiency % of sample powder at different filling speeds (n=3)

[0163] mold 1 rmp 8 rmp 16 rmp 24 rmp 32 rmp 40 rmp 48 rmp 56 rmp round 1.00 1.00±0.00 0.64±0.00 0.32±0.00 0.25±0.01 0.20±0.00 0.16±0.02 0.15±0.00 oval 1.00 0.93±0.00 0.57±0.00 0.28±0.00 0.23±0.01 0.19±0.00 0.15±0.02 0.13±0.00 Alien 1.00 0.96±0.00 0.60±0.02 0.31±0.00 0.26±0.01 0.21±0.01 0.17±0.02 0.15±0.02

[0164] Table 8. Parameters of the fitting equation for sample powder filling efficiency and filling speed

[0165] sample Parameter a Parameter b <![CDATA[R 2 ]]> Maximum fill speed MFS (rmp) round 22.54 -1.30 0.97 10.98 oval 7.31 -0.98 0.96 7.61 Alien 6.82 -0.93 0.98 7.88

[0166] The results showed that the filling results of Panax notoginseng extract powder were inconsistent when different molds were used for filling. The round mold was the best, but there was no significant difference between the elliptical mold and the irregular mold. If the elliptical and irregular tablets are changed later, the change in production capacity can be disregarded.

[0167] In summary, this filling system and evaluation method can be used to scientifically evaluate tablet modification for different powder materials, providing data support for tablet modification research.

[0168] The above description is merely a preferred embodiment of the present invention and does not constitute any limitation on the structure of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention shall fall within the scope of the technical solution of the present invention.

Claims

1. A pharmaceutical powder filling system for tablet compression modification research, characterized in that, include: scraping system, flexible mold system and control system; The scraping system is a dynamic scraper (1) or a static scraper (27); The dynamic scraper (1) is equipped with an agitator (18) driven by a first servo motor (9). The static scraper (1) or dynamic scraper (27) can be selectively fixed to a metal support plate (2) by a combination of positioning pins and fastening screws (10); The agitator wheel (18) in the dynamic scraper (1) is connected to the first servo motor (9) via a transmission shaft (8); A horizontally rotating metal frustum (3) is driven by a second servo motor (15) in the control system, and at least one sample slot (4) for accommodating a filling mold is provided on its surface. The hopper device (7) is located above the dynamic scraper (1) or the static scraper (27) and is used to continuously convey powder during the filling process. The lower end of the hopper device (7) is provided with a rubber sleeve (14) for connecting the dynamic scraper (1). The lower end of the hopper device (7) is provided with an inverted arc-shaped funnel (28); a filling mold (5) is provided below the arc-shaped funnel (28); The flexible mold system includes at least two filling molds (5) with different horizontal cross-sectional shapes, the shape of the filling molds (5) corresponding to the shape of the target tablet to be evaluated, the filling molds (5) being made of transparent resin material and being detachably embedded in the sample slot (4) of the metal frustum; The filling mold (5) has a filling hole with the same shape as the target tablet, and the lower end of the filling hole is connected to a metal spiral push rod mechanism that controls the depth of the filling mold. An image acquisition device is installed in the cavity below the metal support plate (2) to capture images of powder flow in the filling mold (5) during the filling process; The system control display device (11) is located in front of the device and is connected to the control system below; the system control display device (11) is provided with a button (13) for controlling the second start / stop of the first servo motor (9) and a button (12) for controlling the first start / stop of the second servo motor (15). The control system includes a PLC controller for adjusting the rotational speed of the metal frustum and the rotational speed of the agitator wheel in the dynamic scraper.

2. The pharmaceutical powder filling system for tablet compression modification research according to claim 1, characterized in that, The metal support plate (2) is positioned above the metal frustum (3). When the metal frustum (3) rotates, the pharmaceutical powder placed on it is sorted by a scraper and then filled into the filling mold (5) located in the sample slot (4).

3. The pharmaceutical powder filling system for tablet compression modification research according to claim 1, characterized in that, The bottom of the filling mold (5) is provided with a metal spiral push rod mechanism (6). A metal base (21) is embedded in the lower end of the filling mold (5), and the metal base is connected to the filling mold body by bolts; The metal base has a threaded through hole (22) at its center; the threaded through hole (22) and the threaded rod (25) of the spiral push rod mechanism 6 form a threaded pair to achieve coaxial connection; The metal helical push rod mechanism (6) includes, from top to bottom, a piston silicone pad (24); a metal piston body (26); a threaded rod (25); and a knurled handwheel (23).

4. The pharmaceutical powder filling system for tablet compression modification research according to claim 1, characterized in that, The inner wall of the sample groove of the metal frustum (3) is provided with a positioning structure, and the outer wall of the filling mold is provided with a matching positioning structure to achieve precise circumferential and radial positioning of the mold.

5. The pharmaceutical powder filling system for tablet compression modification research according to claim 1, characterized in that, The flexible mold system also includes a transparent observation mold with a rectangular horizontal cross-section, which is larger than the filling mold (5) and is used to magnify and observe the macroscopic flow behavior of the powder.

6. The pharmaceutical powder filling system for tablet compression modification research according to claim 1, characterized in that, The metal frustum (3) is provided with multiple sample slots (4), and the sample slots (4) are provided with countersunk holes (20). The upper outer ring of the filling mold (5) is adapted to the countersunk holes.

7. A method for evaluating tablet compression modification of a pharmaceutical powder filling system based on any one of claims 1-6 for tablet compression modification research, characterized in that, Includes the following steps: S1. Embed the first filling mold corresponding to the shape of the first target tablet into the metal frustum sample slot of the system, and select to install a static scraper or a dynamic scraper; S2. In the selected scraping mode, set the process parameters, control the metal frustum to rotate at multiple different speeds, and measure the filling mass of the pharmaceutical powder in the first filling mold after one revolution at each speed. S3. Calculate the filling efficiency at each rotational speed based on the filling mass. , = Filling mass m at the current rotational speed / Total filling mass M, and then fit the values ​​to obtain the filling efficiency. - Rotational speed V curve; Filling efficiency The fitted curve of the relationship between the rotational speed and the filling speed is a power function. =aX b Where a and b are fixed parameters, and X is the filling speed; S4. Based on the filling efficiency - The rotational speed V curve determines whether the pharmaceutical powder achieves complete filling under the first filling mold and the current process parameters. The limiting filling speed MFS1 when =1); S5. Replace with a second filling mold corresponding to the shape of the second target tablet, and repeat steps S2 to S4 to obtain the corresponding limit filling speed MFS2; S6. Compare MFS1 and MFS2, and estimate the theoretical production capacity based on the formula C = N × MFS. Based on the comparison results of the limiting filling speed and theoretical production capacity, evaluate the feasibility of changing the tablet shape from the first shape to the second shape and its impact on production; where N is the simulated number of die holes of the tablet press.

8. The evaluation method according to claim 7, characterized in that, In step S1, when a dynamic scraper is selected, the rotational speed of the agitator is set and adjusted as an independent process parameter; in step S2, the rotational speed of the agitator is systematically changed to obtain multiple sets of filling efficiencies under different forced feeding intensities. - Rotational speed V curve and corresponding MFS.

9. The evaluation method according to claim 7 or 8, characterized in that, In step S1, the depth of the first or second filling mold is adjusted by the metal spiral push rod mechanism (6) at its bottom; in step S2, under the condition of fixing other parameters, the mold depth is systematically changed to obtain multiple sets of filling efficiencies under different sheet weights or filling amounts. - The rotational speed V curve and the corresponding MFS are used for process window optimization.

10. The evaluation method according to claim 7, characterized in that, During the filling process in step S2, images of the powder filling process are captured simultaneously by the image acquisition device, and the filling uniformity, flow pattern and defects are analyzed to help explain the reasons for the differences in MFS under different molds or process parameters.

Images