Venturi sampling device for granularity tester

Abstract

The utility model provides a venturi sampling device for a granularity tester. The venturi sampling device comprises a base, a pressure sensor, a venturi seat, a venturi component and a nozzle, one side of the bottom of the base is provided with an installation round opening protruding towards the outer wall, and the side wall corresponding to the installation round opening is provided with an installation hole. The air outlet grid is arranged at the bottom of the base, and one end of the air outlet grid abuts against the mounting round opening in the bottom of the base; a pressure sensor is arranged on a mounting hole in the bottom of the base; a sampling window is formed in the middle of the base, and a rectangular air inlet grille is arranged at the top of the base; a venturi seat is arranged above the side of the base, a compressed air inlet is formed in the venturi seat, a pin is arranged on the side wall of the venturi seat, a sealing ring is arranged at the compressed air inlet, and a feeder is arranged above the venturi seat; the venturi assembly is arranged in the venturi seat, and the venturi assembly and the venturi seat can be integrally installed or separated. The device is compact in overall structure, the pollution degree between samples can be reduced, occupied space is reduced, and operability is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of particle size testing instruments, in particular to a Venturi sampling device for a particle size testing instrument. Background Art

[0002] As an important particle size measurement instrument, imaging particle size analyzers have been widely used in powder processing, application, and research. Image particle size analyzers are categorized into dry and wet methods. Dry image particle size analyzers are the primary measurement instrument for certain large, water-soluble powders. Traditional Venturi tube sampling and dispersion methods are one of the primary sampling methods for dry image particle size analyzers. Compressed air is pumped into the Venturi tube via an air compressor, creating suction that draws the powder particles into the tube. The particles are then mixed with the airflow and rapidly pass through a sample detection cell for detection. Powder dispersion is primarily achieved through friction between particles, friction with the tube wall, and shear forces from the turbulent airflow. This method is highly effective for dispersing and sampling most agglomerated dry powders and is currently used by most dry laser particle size analyzers and imaging particle size analyzers on the market. Due to their strong adsorption properties, powder particles are prone to adhering to tube walls or corners during transport. This adsorption can contaminate the subsequent sample, resulting in inaccurate test results. At the same time, the shape of the sprayed powder particle flow is extremely important to the imaging effect and the long-term maintenance-free operation of the instrument. In addition, the long-term spraying action of the high-speed airflow carrying the powder particles will cause wear on the wall of the sample tube.

[0003] In the prior art, such as the solution of CN 113125316 A, the venturi is integrated inside the instrument, and the overall structure is complex and not easy to disassemble and clean. The venturi and the nozzle are separate structures, connected in the middle by a plastic tube. There are many seams, which are prone to residual powder particles. The plastic tube is easy to wear and easy to generate static electricity, causing particle adsorption. The nozzle is a standard circular tube shape, and the shape of the sprayed powder particle flow is conical, which is not conducive to imaging and is more likely to contaminate the glass at the sampling window. The protective gas pipeline is an integral open cavity. In order to meet the conditions for forming laminar flow in fluid dynamics, the protective gas pipeline needs to be significantly extended, resulting in the volume of the injector taking up a lot of space. Utility Model Content

[0004] The purpose of the utility model is to provide a Venturi sampling device for a particle size tester to solve the problems raised in the above background technology.

[0005] To achieve the above-mentioned purpose, the present invention provides the following technical solutions:

[0006] A venturi sampling device for a particle size tester, comprising a base, a pressure sensor, a venturi seat, a venturi assembly and a nozzle;

[0007] A mounting hole is provided on the side wall corresponding to the mounting hole;

[0008] The air outlet grille is arranged at the bottom of the base, and one end of the air outlet grille is pressed against the mounting circular opening at the bottom of the base; a pressure sensor is provided on the mounting hole at the bottom of the base;

[0009] A sampling window is provided in the middle of the base, and a rectangular air intake grille is provided on the top of the base;

[0010] A venturi seat is arranged above the base side, the venturi seat is provided with a compressed air inlet, a pin is provided on the side wall, and a feeder is provided above the venturi seat; the venturi assembly is arranged in the venturi seat, and the venturi assembly can be installed or detached from the venturi seat as a whole.

[0011] The preferred embodiment of the Venturi sampling device for a particle size analyzer is that the Venturi assembly consists of a base, a funnel, a nozzle, a dispersion pipe and a wrench;

[0012] The top of the base is provided with a protrusion, the end surface of the protrusion passes through the base to form a conical funnel, the end surface of the protrusion is the funnel mouth, and the two sides of the inner cavity funnel of the base are respectively provided with a compressed air interface and a pipeline interface;

[0013] Open slides are provided on both sides of the base, and the slides are clamped on the pins on the inner wall of the venturi seat to connect the venturi assembly to the venturi seat;

[0014] Wrenches are provided on both sides of the protrusion on the top of the base, the wrenches are connected to the base through a shaft, and the wrenches can rotate along the shaft;

[0015] The compressed air interface in the base is connected to the compressed air inlet on the venturi seat, and a sealing ring is provided between the two;

[0016] One end of the dispersion pipeline is inserted into the round hole reserved in the base and plugged into the pipeline interface, and is rigidly connected to the funnel as a whole. The other end of the dispersion pipeline is provided with a nozzle, which is plugged into the top of the base and located in the center of the air intake grille.

[0017] The preferred embodiment of the Venturi sampling device for a particle size tester is that the sampling window is made of a highly transparent material and the dispersion pipeline is made of stainless steel.

[0018] The preferred embodiment of the Venturi sampling device for a particle size tester is that one side of the wrench shaft is cut into a flat surface, and the Venturi assembly and the Venturi seat are locked by rotating the arc surface to coincide with the groove of the base.

[0019] The preferred solution of the Venturi sampling device for a particle size tester is that the nozzle is slotted along its axial direction, and the nozzle forms two symmetrical baffles on the dispersion pipeline, and the direction of the baffles is consistent with the direction of the dispersion pipeline opening.

[0020] The preferred embodiment of the Venturi sampling device for a particle size tester is that the nozzle can be grooved in different shapes according to the effect of maintaining a flat state of the particle flow when ejecting the nozzle. The grooves are rectangular, V-shaped, U-shaped or other shapes that are favorable for maintaining a flat state of the particle flow when ejecting the nozzle.

[0021] The preferred embodiment of the Venturi sampling device for a particle size tester is that the air outlet grille is a thin metal plate in an L-shape, but not limited to an L-shape; the spacing between the grille plates on the side with a shorter air flow path is smaller, and the spacing between the grille plates on the side with a longer air flow path is larger, to ensure that the sample flow remains centered and in a flowing state when passing through the sampling window.

[0022] The working principle of a Venturi sampling device for a particle size tester is as follows: after aligning the slide of the Venturi assembly with the pin on the Venturi seat, the Venturi assembly is slid into the Venturi seat, and the wrench is turned to complete the installation of the Venturi assembly. Powder particles are placed in the feeder, and the vacuum cleaner is connected to the interface at the bottom of the base 1. The vacuum cleaner is started, and air is sucked in through the air intake grille. After the pressure sensor detects that the vacuum cleaner pressure is normal, compressed air is introduced into the compressed air inlet, and the feeder operates, conveying the pre-placed powder particles into the funnel. The powder particles conveyed to the funnel are carried by the compressed air and ejected from the nozzle through the dispersion pipeline to form a particle flow. Due to the slots on the nozzle, the particle flow is first ejected in the direction of the nozzle slots when ejected, and the pressure of the particle flow decreases at the same time. After the pressure decreases, the particle flow is completely ejected from the nozzle, forming a thin fan-shaped particle flow. At the same time, the particle flow is constrained by the protective air sucked in through the air intake grille and passes through the sampling window in a stable flat state. The particle flow and protective air are restricted by the air outlet grille, pass through the sampling window in a relatively central flow state, and are then recovered by the vacuum cleaner.

[0023] Beneficial effects

[0024] The Venturi assembly of the present invention can be quickly disassembled and assembled using a wrench, making it easy to clean and operate. The rectangular design of the air inlet grille conforms to the basic principles of fluid dynamics, forming a laminar protective gas flow in a compact size to ensure a stable flow state of the particle flow. The air outlet grille is L-shaped, but not limited to the L-shape. The grille plates on the side with a shorter air flow path have a smaller spacing, while the grille plates on the side with a longer air flow path have a larger spacing, ensuring that the sample flow remains centered and in a flowing state when passing through the sampling window, thereby improving the efficiency and representativeness of the sampling.

[0025] The nozzle in this solution features a special shape that keeps the sample flat as it exits the nozzle, aligning with the focal plane of the optical path, improving sampling efficiency. Because the particle flow is stabilized and constrained, a laminar flow pattern is formed, protecting the sampling window and reducing cleaning and maintenance efforts.

[0026] The pipes are made of stainless steel, which is wear-resistant and does not generate static electricity. Users do not need to frequently replace consumables, and no static electricity is generated, which is conducive to particle dispersion.

[0027] The utility model has a compact overall structure and no dead angles, which reduces the degree of contamination between samples, reduces space occupation, reduces the weight of the instrument, and improves operability. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 The present invention is a cross-sectional view of a Venturi sampling device for a particle size tester;

[0029] Figure 2 A top view of a Venturi sampling device for a particle size tester;

[0030] Figure 3 A side view of a Venturi sampling device for a particle size tester;

[0031] Figure 4 This is a diagram of the Venturi seat structure;

[0032] Figure 5 This is a structural diagram of the Venturi component;

[0033] Figure 6 This is a cross-sectional view of the Venturi component;

[0034] Figure 7 Unlock the state section diagram for the Venturi assembly;

[0035] Figure 8 This is a cross-sectional view of the Venturi assembly in the locked state;

[0036] Figure 9 Schematic diagram of the Venturi assembly removal process.

[0037] Among them, 1. Base, 2. Air outlet grille, 3. Pressure sensor, 4. Sampling window, 5. Air inlet grille, 6. Sealing ring, 7. Venturi seat, 8. Compressed air inlet, 9. Feeder, 10. Venturi assembly, 11. Nozzle, 12. Pin, 13. Base, 14. Wrench, 15. Slide, 16. Funnel, 17. Compressed air interface, 18. Dispersion pipeline, 19. Pipe interface, 20. Groove. DETAILED DESCRIPTION

[0038] The present invention will be described clearly and completely below with reference to the following embodiments. It is obvious that the embodiments described are only a portion of the embodiments of the present invention, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort are also within the scope of protection of the present invention.

[0039] Please see the attached Figure 1-9 , a Venturi sampling device for a particle size tester, comprising a base 1, a pressure sensor 3, a Venturi seat 7, a Venturi assembly 10 and a nozzle 11;

[0040] The bottom side of the base 1 is provided with a mounting circular opening protruding toward the outer wall, and a mounting hole is provided on the side wall corresponding to the mounting circular opening;

[0041] The air outlet grille 2 is arranged at the bottom of the base 1, and one end of the air outlet grille 2 is pressed against the mounting circular opening at the bottom of the base 1; a pressure sensor 3 is provided on the mounting hole at the bottom of the base 1;

[0042] A sampling window 4 is provided in the middle of the base 1, and a rectangular air intake grille 5 is provided on the top of the base 1;

[0043] A venturi seat 7 is arranged above the side of the base 1, and a compressed air inlet 8 is provided on the venturi seat 7. A pin 12 is provided on the side wall, and a sealing ring 6 is provided at the compressed air inlet. A feeder 9 is provided above the venturi seat 7; a venturi assembly 10 is arranged in the venturi seat 7, and the venturi assembly 10 can be installed or detached from the venturi seat 7 as a whole.

[0044] The venturi assembly 10 is composed of a base 13, a funnel 16, a nozzle 11, a dispersion pipe 18 and a wrench 14;

[0045] The top of the base 13 is provided with a protrusion, the end surface of the protrusion passes through the base to form a conical funnel 16, the end surface of the protrusion is a funnel mouth, and the two sides of the inner cavity funnel 16 of the base 13 are respectively provided with a compressed air interface 17 and a pipeline interface 19;

[0046] The base 13 is provided with open chute 15 on both sides, and the chute 15 is clamped on the pin 12 on the inner wall of the venturi seat 7 to connect the venturi assembly 10 to the venturi seat 7;

[0047] The top of the base 13 is provided with wrenches 14 on both sides of the protrusion. The wrenches 14 are connected to the base 13 through an axis, and the wrenches 14 can rotate along the axis.

[0048] The compressed air interface 17 in the base 13 is connected to the compressed air inlet 8 on the venturi seat, and a sealing ring 6 is provided between the two;

[0049] One end of the dispersion pipe 18 is inserted into the round hole reserved in the base 13 and plugged into the pipe interface 19, and is rigidly connected to the funnel 16 as a whole. The other end of the dispersion pipe 18 is provided with a nozzle 11, which is plugged into the top of the base and located in the center of the air intake grille 5.

[0050] The sampling window 4 is made of highly transparent material, and the dispersion pipeline 18 is made of stainless steel.

[0051] One side of the shaft of the wrench 14 is cut into a flat surface, and the venturi assembly 10 and the venturi seat 7 are locked by rotating the arc surface to coincide with the groove 20 of the base 13.

[0052] The nozzle 11 is slotted along its axial direction, and the nozzle 11 forms two symmetrical baffles on the dispersion pipeline 18 , and the direction of the baffles is consistent with the opening direction of the dispersion pipeline 18 .

[0053] The nozzle 11 can be slotted in different shapes according to the effect of keeping the particle flow flat when ejecting the nozzle. The slot can be rectangular, V-shaped, U-shaped or other shapes that are favorable for keeping the particle flow flat when ejecting the nozzle.

[0054] The air outlet grille 2 is a metal thin plate, which is L-shaped, but not limited to L-shaped; the grille plate spacing on the side with a shorter air flow path is smaller, and the grille plate spacing on the side with a longer air flow path is larger, ensuring that the sample flow remains centered and flowing when passing through the sampling window.

[0055] The working principle of a venturi sampling device for a particle size tester is as follows: after aligning the slide groove 15 of the venturi component 10 with the pin 12 on the venturi seat 7, the venturi component 10 is slid into the venturi seat 7, and the wrench 14 is turned to complete the installation of the venturi component 10. Powder particles are placed into feeder 9, the vacuum cleaner is connected to the interface at the bottom of base 1, and the vacuum cleaner is started. Air is drawn in through air intake grille 5. After pressure sensor 3 detects normal vacuum cleaner pressure, compressed air is introduced into compressed air inlet 8, and feeder 9 operates, conveying the pre-placed powder particles into hopper 16. The powder particles in hopper 16 are carried by the compressed air and ejected from nozzle 11 through dispersion pipe 18 to form a particle stream. Due to the slots in the nozzle, the particle stream is initially ejected in the direction of the slots in nozzle 18, while the pressure of the particle stream decreases. After the pressure drops, the particle stream is completely ejected from the nozzle, forming a thin fan-shaped particle stream. Simultaneously, the particle stream is constrained by the protective air drawn in through air intake grille 5 and passes through sampling window 4 in a stable, flat state. The particle stream and protective air are restricted by air outlet grille 2, passing through sampling window 4 in a relatively central flow state before being recovered by the vacuum cleaner.

[0056] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A Venturi sampling device for a particle size analyzer, characterized in that: Includes base, pressure sensor, venturi seat, venturi assembly and nozzle; A mounting hole is provided on the side wall corresponding to the mounting hole; The air outlet grille is arranged at the bottom of the base, and one end of the air outlet grille is pressed against the mounting circular opening at the bottom of the base; a pressure sensor is provided on the mounting hole at the bottom of the base; A sampling window is provided in the middle of the base, and a rectangular air intake grille is provided on the top of the base; A venturi seat is arranged above the base side, the venturi seat is provided with a compressed air inlet, a pin is provided on the side wall, and a feeder is provided above the venturi seat; the venturi assembly is arranged in the venturi seat, and the venturi assembly can be installed or detached from the venturi seat as a whole.

2. A Venturi sampling device for a particle size tester according to claim 1, characterized in that: The venturi assembly consists of a base, a funnel, a nozzle, a dispersion pipe and a wrench; The top of the base is provided with a protrusion, the end surface of the protrusion passes through the base to form a conical funnel, the end surface of the protrusion is the funnel mouth, and the two sides of the inner cavity funnel of the base are respectively provided with a compressed air interface and a pipeline interface; Open slides are provided on both sides of the base, and the slides are clamped on the pins on the inner wall of the venturi seat to connect the venturi assembly to the venturi seat; Wrenches are provided on both sides of the protrusion on the top of the base, the wrenches are connected to the base through a shaft, and the wrenches can rotate along the shaft; The compressed air interface in the base is connected to the compressed air inlet on the venturi seat, and a sealing ring is provided between the two; One end of the dispersion pipeline is inserted into the round hole reserved in the base and plugged into the pipeline interface, and is rigidly connected to the funnel as a whole. The other end of the dispersion pipeline is provided with a nozzle, which is plugged into the top of the base and located in the center of the air intake grille.

3. A Venturi sampling device for a particle size analyzer according to claim 1, characterized in that: The sampling window is made of highly transparent material, and the dispersion pipeline is made of stainless steel.

4. A Venturi sampling device for a particle size tester according to claim 2, characterized in that: One side of the wrench shaft is cut into a plane, and the venturi component and the venturi seat are locked by rotating the arc surface to coincide with the groove of the base.

5. The Venturi sampling device for a particle size analyzer according to claim 2, characterized in that: The nozzle is grooved along its axial direction, and the nozzle forms two symmetrical baffles on the dispersion pipeline, and the direction of the baffles is consistent with the opening direction of the dispersion pipeline.

6. A Venturi sampling device for a particle size tester according to claim 5, characterized in that: The base, funnel, compressed air interface and pipeline interface are an integral structure; The nozzle can be slotted in different shapes according to the effect of keeping the particle flow in a flat state when ejecting the nozzle, and the slots are rectangular, V-shaped, and U-shaped.

7. A Venturi sampling device for a particle size analyzer according to claim 1, characterized in that: The air outlet grille is a metal sheet in an L-shape, but is not limited to the L-shape; The grid plates on the side with a shorter air flow path have smaller spacing, while the grid plates on the side with a longer air flow path have larger spacing, ensuring that the sample flow remains centered and flowing when passing through the sampling window.

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