Powder electrostatic accumulation characteristic detector

Abstract

The invention provides a powder electrostatic accumulation characteristic detector, and relates to the technical field of powder material electrostatic detection instruments, the powder electrostatic accumulation characteristic detector comprises an experiment box, and a chute, a Faraday cup, a humidity adjusting device, a temperature adjusting device and a feeding device arranged in the experiment box; the Faraday cup is located below the bottom end of the sliding groove. The humidity adjusting device is used for adjusting the humidity in the experiment box; the temperature adjusting device is used for adjusting the temperature in the experiment box; the feeding device comprises a lifting mechanism, an overturning plate and a Faraday cup fixed to the overturning plate, the end, close to the top end of the sliding groove, in the overturning plate is hinged, the lifting mechanism is connected to the position, away from the top end of the sliding groove, in the overturning plate, and the Faraday cup is used for containing a powder sample and pouring the powder sample into the top end of the sliding groove during overturning; according to the invention, the static accumulation characteristics of the powder sample under different temperature and humidity environments can be obtained, the experimental data is more accurate, and data support can be provided for powder static prevention in actual production.

Description

Technical Field

[0001] The present invention relates to the technical field of electrostatic detection instruments for powder materials, and particularly to a powder electrostatic accumulation characteristic detector. Background Art

[0002] Powder materials are widely used in fields such as aerospace, military defense, chemical engineering, electronic technology, and food processing, and play a crucial role in the development of modern industry and technology. However, powder materials will inevitably generate static electricity through friction during production, transportation, storage, and use. In recent years, powder material combustion and explosion accidents caused by static electricity have occurred frequently, resulting in serious casualties and property losses, and have attracted great attention from powder industry practitioners. Testing the electrostatic accumulation characteristics of powder materials by simulating the electrification process during production and evaluating the electrostatic safety of powder materials is of great significance for preventing electrostatic hazards.

[0003] Existing research shows that the electrification process of powder materials is usually affected by a combination of various factors such as external conditions (temperature, relative humidity), force conditions (friction force), particle geometric conditions (size, shape, contact area, roughness), and chemical conditions (presence of antistatic agents, mixing with chemical substances). For example, the level of environmental humidity will seriously affect the amount of water molecules adsorbed on the surface of powder materials, affect the surface conductivity of powder materials, that is, the level of surface work function, thereby affecting its ability to leak static charges, and ultimately have a significant impact on the electrostatic accumulation characteristics of powder materials. In addition, environmental temperature will also cause changes in the conductivity of powder materials, the mobility of electrons and impurities, and the state of water adsorbed on the surface of powder materials. Therefore, it is still quite difficult to accurately characterize the electrostatic hazard of powder materials and quantitatively analyze the influence laws of environmental temperature and humidity, and friction force conditions on the electrostatic accumulation characteristics of powder materials.

[0004] In addition, the electrostatic accumulation of powder materials caused by friction, contact, separation, or other physical processes will lead to the generation of static voltage on the surface or inside of powder materials. Static voltage is one of the important physical parameters for characterizing electrostatic safety. When the electrostatic field strength reaches the breakdown field strength of the environmental medium, it will cause the occurrence of electrostatic discharge phenomena. However, there is currently a lack of multi-parameter synchronous detection instruments for the electrostatic accumulation amount and static voltage of powder materials, and there is still a lack of effective equipment basis and evaluation methods for establishing the quantitative function equation between the static voltage and electrostatic charge amount of powder materials under different test conditions.

[0005] In summary, although the currently disclosed electrostatic accumulation test equipment can evaluate the electrostatic accumulation amount parameter of powder materials, there is still a lack of effective detection equipment and method references for evaluating the quantitative relationships between environmental temperature and humidity, powder stress conditions, chute material, geometric and chemical conditions of powder materials, and powder electrostatic accumulation amount and static voltage. There is an urgent need to develop a new test instrument with multi-factor parameter control to lay a foundation for the accurate evaluation of electrostatic safety prevention and control technology for powder materials. Summary of the Invention

[0006] The purpose of the present invention is to provide a powder electrostatic accumulation characteristic detector to solve the problems existing in the above-mentioned prior art. By setting a temperature adjustment device and a humidity adjustment device inside the experimental box, it is possible to detect the electrostatic accumulation amount during the friction process of powder samples under different temperature and humidity environmental conditions, reflect the electrostatic accumulation characteristics of powder materials, and provide data support for the comprehensive evaluation of the electrostatic safety of powder materials.

[0007] To achieve the above purpose, the present invention provides the following solutions:

[0008] A powder electrostatic accumulation characteristic detector includes an experimental box, as well as a chute, a Faraday cylinder, a humidity adjustment device, a temperature adjustment device, and a feeding device arranged in the experimental box. The chute is used for the powder sample to slide down; the Faraday cylinder is located below the bottom end of the chute; the humidity adjustment device is used to adjust the humidity in the experimental box; the temperature adjustment device is used to adjust the temperature in the experimental box; the feeding device includes a lifting mechanism, a turning plate, and a Faraday cup fixed on the turning plate. The end of the turning plate close to the top end of the chute is hinged, and the position of the turning plate far from the top end of the chute is connected to the lifting mechanism. The lifting mechanism is used to make the turning plate rotate around the hinged end, and the Faraday cup is used to hold the powder sample and pour the powder sample into the top end of the chute when it rotates.

[0009] As an embodiment, the lifting mechanism includes a bidirectional rotating motor fixedly arranged, a first connecting rod, and a second connecting rod. The output end of the bidirectional rotating motor is fixedly connected to one end of the first connecting rod, the other end of the first connecting rod is hinged to one end of the second connecting rod, and the other end of the second connecting rod is hinged to the turning plate.

[0010] As an embodiment, the lifting mechanism further includes a fixedly arranged fixed platform. The turning plate and the lifting mechanism are both arranged on the fixed platform. A first weight sensor is also arranged on the fixed platform. The first weight sensor is located at the bottom of the turning plate in the non-rotated state and is used to obtain the mass of the powder sample in the Faraday cup.

[0011] As an embodiment, a blanking pipe made of metal and communicating with the Faraday cylinder is arranged below the bottom end of the chute. The blanking pipe includes a straight pipe section and an annular convex section. The convex section has an annular accommodation cavity. An insulating layer coplanar with the inner wall of the straight pipe section is arranged in the accommodation cavity. An annular static voltage test electrode is arranged on the outer wall of the insulating layer.

[0012] As an embodiment, the humidity adjustment device includes a humidifying hole, a moisture exhaust pump and a circulation fan arranged in the experimental box. The humidifying hole is connected to a humidifier. The moisture exhaust pump and the circulation fan are located on different walls of the experimental box. A first humidity sensor is arranged near the moisture exhaust pump, and a second humidity sensor is arranged near the circulation fan.

[0013] As an embodiment, the temperature adjustment device includes a heater. The heat dissipation end of the heater is located inside the experimental box, and a temperature sensor is also arranged in the experimental box.

[0014] As an embodiment, the heater includes a temperature control water tank, a circulation water pump and a heat exchange pipe. The heat exchange pipe is located inside the experimental box. Both ends of the heat exchange pipe are communicated with the temperature control water tank through pipelines. The circulation water pump is located on the pipeline between the heat exchange pipe and the temperature control water tank.

[0015] As an embodiment, an angle adjustment plate and an arc-shaped hole are further arranged on the back plate of the experimental box. The chute is fixedly connected to the angle adjustment plate through a card slot. The top end of the angle adjustment plate is rotatably connected to the experimental box, and the bottom end of the angle adjustment plate is detachably connected to the position where the arc-shaped hole is located. The Faraday cylinder is arranged on an L-shaped plate. The vertical plate in the L-shaped plate is hinged to the bottom end of the angle adjustment plate, and a second weight sensor for weighing the Faraday cylinder is arranged on the horizontal plate in the L-shaped plate.

[0016] As an embodiment, a connecting bolt is further included. The connecting bolt sequentially penetrates through the vertical plate of the L-shaped plate, the angle adjustment plate and the arc-shaped hole on the back plate, and a locking nut is connected to the end of the connecting bolt.

[0017] As an embodiment, a door panel is arranged on the experimental box. The door panel and the wall surface of the experimental box both include an electromagnetic shielding layer, a heat insulation layer and an electrostatic protection layer which are sequentially arranged from the inside to the outside.

[0018] The present invention has the following technical effects compared with the prior art:

[0019] 1. The present invention can detect the electrostatic accumulation amount during the friction process of powder samples under different temperature and humidity environmental conditions by setting a temperature adjustment device and a humidity adjustment device inside the experimental chamber, providing data support for the comprehensive evaluation of the electrostatic safety of powder materials.

[0020] 2. The present invention concentrates the entire experimental process inside the experimental chamber, avoiding the influence of the external environment (temperature, humidity, static electricity, etc.) on the experimental process, and ensuring the stability of the test results and the accuracy of the experimental data.

[0021] 3. The present invention is provided with a feeding device in the experimental chamber. By using the feeding device, the powder sample can be poured into the chute, eliminating the need for staff to feed. After the internal environment of the experimental chamber is adjusted to the set value, it avoids the environmental fluctuation in the experimental chamber caused by the staff entering the experimental chamber again to pour the powder sample, which increases the experimental data error, thus further ensuring the accuracy of the experimental data.

[0022] 4. The present invention independently quantifies the initial charge amount of the powder sample before friction through the Faraday cup in the feeding device, eliminating the interference of the initial state of the sample on the detection result of the electrostatic accumulation characteristics of the powder, and improving the detection accuracy.

[0023] 5. The present invention is provided with a blanking pipe at the bottom of the chute, and an annular static voltage test electrode is arranged inside the blanking pipe, which can detect the static voltage of the powder sample and can more comprehensively reflect the electrostatic accumulation characteristics of the powder sample. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0025] Figure 1 It is a schematic structural diagram of a powder electrostatic accumulation characteristic detector in an embodiment of the present invention;

[0026] Figure 2 It is a schematic structural diagram of a feeding device in an embodiment of the present invention;

[0027] Figure 3 It is a schematic structural diagram of the cooperation between an L-shaped plate, an angle adjustment plate and a back plate in an embodiment of the present invention;

[0028] Figure 4 It is a schematic structural diagram of a blanking pipe in an embodiment of the present invention;

[0029] Figure 5Schematic diagram of the control principle of the powder electrostatic accumulation characteristic detector in an embodiment of the present invention;

[0030] Figure 6 Schematic diagram of the test results of the electrostatic accumulation amount and static voltage of TATB (triaminotrinitrobenzene) at different temperatures in an embodiment of the present invention;

[0031] Figure 7 Schematic diagram of the test results of the electrostatic accumulation amount and static voltage of TATB (triaminotrinitrobenzene) at different humidities in an embodiment of the present invention.

[0032] Description of reference numerals:

[0033] 1. Experimental chamber; 2. Slide groove; 3. Faraday cylinder; 4. Feeding device; 5. Aggregate hopper; 6. Display screen; 7. Feeding hopper; 8. Host computer; 9. Feed pipe; 10. Convex section; 11. Ring static voltage test electrode; 12. Insulating layer; 13. Humidifying hole; 14. Moisture exhaust pump; 15. Circulation fan; 16. Heat exchange pipe; 17. First temperature and humidity sensor; 18. Second temperature and humidity sensor; 19. Angle adjusting plate; 20. L-shaped plate; 21. Back plate; 22. Connecting bolt; 23. Locking nut; 24. Arc-shaped hole; 25. Door panel; 26. Back plate box; 27. Second weight sensor; 41. Flip plate; 42. Faraday cup; 43. Bidirectional rotating motor; 44. First connecting rod; 45. Second connecting rod; 46. Fixed table; 47. First weight sensor. Detailed implementation manners

[0034] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0035] The purpose of the present invention is to provide a powder electrostatic accumulation characteristic detector to solve the problems existing in the prior art. By setting a temperature adjusting device and a humidity adjusting device inside the experimental chamber, it is possible to detect the electrostatic accumulation amount during the friction process of the powder sample under different temperature and humidity environmental conditions, reflect the electrostatic accumulation characteristics of the powder material, and provide data support for the comprehensive evaluation of the electrostatic safety of the powder material.

[0036] To make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific implementation manners.

[0037] As Figures 1 to 7As shown in the figure, this embodiment provides a powder electrostatic accumulation characteristic detector, which includes an experimental chamber 1, a chute 2, a Faraday cylinder 3, a humidity adjustment device, a temperature adjustment device, and a feeding device 4 arranged in the experimental chamber 1. The chute 2 is used for the powder sample to slide down; the Faraday cylinder 3 is located below the bottom end of the chute 2 and is used to receive the sliding powder sample. In order to facilitate the reception of the powder sample, a collecting hopper 5 is arranged below the bottom end of the chute 2, and the Faraday cylinder 3 is arranged below the collecting hopper 5. The humidity adjustment device is used to adjust the humidity in the experimental chamber 1; the temperature adjustment device is used to adjust the temperature in the experimental chamber 1. The feeding device 4 includes a lifting mechanism, a turning plate 41, and a Faraday cup 42 fixed on the turning plate 41. The end of the turning plate 41 close to the top end of the chute 2 is hinged, and the position of the turning plate 41 far from the top end of the chute 2 is connected to the lifting mechanism. When the output end of the lifting mechanism raises the position of the turning plate 41 far from the top end of the chute 2, the turning plate 41 can be turned. The Faraday cup 42 is used to hold the powder sample. When the turning plate 41 turns, it will drive the Faraday cup 42 to turn. When the Faraday cup 42 turns, it will pour the powder sample into the top end of the chute 2, so that the powder sample slides down from the top end of the chute 2 and finally falls into the Faraday cylinder 3 from the collecting hopper 5. In order to facilitate the centralized transportation of the powder sample and prevent the powder sample from falling outside the chute 2, a feeding hopper 7 is arranged at the top end of the chute 2. The feeding hopper 7 is located below the cup mouth of the Faraday cup 42 in the turned state and is used to receive the powder sample.

[0038] In this embodiment, the Faraday cup 42 is used to obtain the initial charge quantity Q1 of the powder sample, the Faraday cylinder 3 is used to obtain the charge quantity Q2 of the powder sample after it slides down, the first weight sensor 47 obtains the initial mass m1 of the powder sample in the Faraday cup 42, and the second weight sensor 27 obtains the mass m2 of the powder sample that falls into the Faraday cylinder 3 after friction through the chute. Thus, the electrostatic accumulation quantity of the powder sample (Q2 / m2 - Q1 / m1) under different temperature and humidity environments can be obtained. Compared with traditional powder electrostatic accumulation quantity testing equipment, the interference of the initial state of the sample on the detection result of the powder electrostatic accumulation characteristics is eliminated, and the detection accuracy is improved. Moreover, the material of the chute 2 can be changed to obtain the electrostatic accumulation quantity of the powder sample corresponding to different materials of the chute 2. In addition, in this embodiment, the entire experimental process is concentrated inside the experimental chamber 1, avoiding the influence of the external environment (temperature, humidity, static electricity, etc.) on the experimental process, and ensuring the stability of the test result and the accuracy of the experimental data. Further, in this embodiment, a feeding device 4 is provided in the experimental chamber 1. By using the feeding device 4, the powder sample can be poured into the chute 2, eliminating the need for staff to add the sample. After the environment inside the experimental chamber 1 is adjusted to the set value, if the staff enters the experimental chamber 1 again to pour the powder sample, it will cause fluctuations in the environment inside the experimental chamber 1 and increase the error of the experimental data, thus further ensuring the accuracy of the experimental data. Moreover, in this embodiment, by providing a temperature regulating device and a humidity regulating device inside the experimental chamber 1, the electrostatic accumulation quantity (unit: nC·g -1 ) during the friction process of the powder sample under different temperature and humidity environmental conditions can be detected, providing data support for the comprehensive evaluation of the electrostatic safety of powder materials.

[0039] In this embodiment, the lifting mechanism includes a bidirectional rotating motor 43 fixedly arranged, a first connecting rod 44, and a second connecting rod 45. The output end (output shaft) of the bidirectional rotating motor 43 is fixedly connected to one end of the first connecting rod 44. The other end of the first connecting rod 44 is hinged to one end of the second connecting rod 45. The other end of the second connecting rod 45 is hinged to the flipping plate 41. When the output end of the bidirectional rotating motor 43 rotates, through the movement of the first connecting rod 44 and the second connecting rod 45, the flipping plate 41 can be driven to perform a flipping motion.

[0040] In this embodiment, the lifting mechanism further includes a fixed platform 46 fixedly arranged. The flipping plate 41 and the lifting mechanism are both arranged on the fixed platform 46. Specifically, the fixed platform 46 includes a horizontal tabletop. At the end of the horizontal tabletop, a fixing plate is vertically arranged. The top end of the fixing plate is hinged to the flipping plate 41. A first weight sensor 47 is also arranged on the fixed platform 46. The first weight sensor 47 is located at the bottom of the flipping plate 41 in the non-flipped state and is used to obtain the mass m1 of the powder sample in the Faraday cup 42.

[0041] In this embodiment, a blanking pipe 9 made of metal and communicating with the Faraday cylinder 3 is arranged below the bottom end of the chute 2. The blanking pipe 9 includes a straight pipe section and an annular protruding section 10. The protruding section 10 has an annular accommodating cavity, and an insulating layer 12 coplanar with the inner wall of the straight pipe section is arranged in the accommodating cavity. An annular static voltage test electrode 11 is arranged on the outer wall of the insulating layer 12. Among them, the annular static voltage test electrode 11 is used to detect the static voltage V (unit: V) of the powder sample in real time. The blanking pipe 9 made of metal can play a shielding role to avoid the influence of static electricity in the external environment on the measurement of the charge amount of the powder sample. By measuring the static voltage of the powder sample, it is convenient to comprehensively understand the static charge accumulation characteristics of the powder sample.

[0042] The humidity adjustment device in this embodiment includes a humidifying hole 13, a dehumidifying pump 14, and a circulation fan 15 arranged in the experimental chamber 1. The humidifying holes 13 are evenly distributed on the bottom plate of the experimental chamber 1 and are connected to a humidifier. The dehumidifying pump 14 and the circulation fan 15 are located on different walls inside the experimental chamber 1. Specifically, the dehumidifying pump 14 is located on the side wall of the experimental chamber 1, and the circulation fan 15 can be located on the top plate of the experimental chamber 1. The dehumidifying pump 14 and the humidifier are used to adjust the humidity inside the experimental chamber 1, and the circulation fan 15 is used to promote the air circulation inside the experimental chamber 1, which is beneficial to the uniform distribution of the air humidity and temperature in the laboratory. A first humidity sensor is arranged at a position inside the experimental chamber 1 close to the dehumidifying pump 14, and a second humidity sensor is arranged at a position close to the circulation fan 15. The first humidity sensor detects the temperature and humidity state near the dehumidifying pump 14, and the second humidity sensor detects the temperature and humidity state near the circulation fan 15. When the humidity parameters detected by the first humidity sensor and the second humidity sensor are the same and meet the preset humidity test conditions, the static charge accumulation characteristic test of the powder sample is performed to achieve uniform distribution and precise control of the humidity in the test environment.

[0043] The temperature adjustment device in this embodiment includes a heater. The heat dissipation end of the heater is located inside the experimental chamber 1, and a temperature sensor is also arranged inside the experimental chamber 1. Specifically, the heater includes a temperature control water tank, a circulation water pump, and a heat exchange tube 16. The heat exchange tube 16 is located inside the experimental chamber 1, and both ends of the heat exchange tube 16 are communicated with the temperature control water tank through pipelines. The circulation water pump is located on the pipeline between the heat exchange tube 16 and the temperature control water tank. The circulation water pump sends the warm water in the temperature control water tank into the heat exchange tube 16, thereby adjusting the temperature inside the experimental chamber 1. The heat exchange tube 16 is a serpentine coil, and the temperature degree in the temperature control water tank can be adjusted according to experimental needs. In order to detect the temperature inside the experimental chamber 1, a temperature sensor needs to be arranged inside the experimental chamber 1. In order to reduce the number of detection elements, the first humidity sensor and the second humidity sensor can be selected as the first temperature and humidity sensor 17 and the second temperature and humidity sensor 18 that simultaneously have the temperature detection function.

[0044] The heater can also be a resistance heating wire.

[0045] In this embodiment, the back plate 21 of the experimental box 1 is also provided with an angle adjustment plate 19 and an arc hole 24. The slide 2 is fixedly connected to the angle adjustment plate 19 through a slot, the top of the angle adjustment plate 19 is rotatably connected to the experimental box 1, and the bottom of the angle adjustment plate 19 is detachably connected to the position where the arc hole 24 is located; the Faraday cup 3 is provided on the L-shaped plate 20, the vertical plate in the L-shaped plate 20 is hinged to the bottom of the angle adjustment plate 19, and the horizontal plate in the L-shaped plate 20 is provided with a second weight sensor 27 for weighing the Faraday cup 3 to obtain the mass of the powder sample in the Faraday cup 3. Specifically, in this embodiment, a connecting bolt 22 is also included, which passes through the vertical plate of the L-shaped plate 20, the angle adjustment plate 19 and the arc hole 24 on the back plate 21 in sequence, and a locking nut 23 is connected to the end of the connecting bolt 22. By changing the position of the connecting bolt 22 on the arc hole 24, the inclination angle of the angle adjustment plate 19 and the slide chute 2 can be changed, thereby changing the static voltage V of the powder sample under different gravity and the charge Q2 after sliding.

[0046] In this embodiment, a door panel 25 is provided on the experimental box 1, and the door panel 25 and the wall surface of the experimental box 1 include an electromagnetic shielding layer, a thermal insulation layer and an electrostatic protection layer which are arranged in sequence from the inside to the outside, so as to reduce the degree to which the environment inside the experimental box 1 is affected by the external environment. The electromagnetic shielding layer provides efficient electromagnetic shielding to prevent external electromagnetic interference. The thermal insulation layer maintains the temperature stability of the test environment inside the experimental box 1 to prevent heat loss or external heat transmission. The electrostatic protection layer quickly conducts away the electrostatic charge through the grounding design to prevent static electricity from affecting the test area.

[0047] In this embodiment, the door panel 25 and other wall surfaces of the experimental box 1 should be made as transparent as possible to facilitate the staff to observe the internal conditions of the experimental box 1.

[0048] This embodiment also includes a controller, which is in communication connection with the first temperature and humidity sensor 17, the second temperature and humidity sensor 18, the bidirectional rotating motor and other electrical components, and is used to collect and process experimental data, and also control the bidirectional rotating motor. Specifically, the controller includes a signal acquisition and processing module and a host computer 8. The controller can be set in the backboard box 26 on the back of the experimental box 1, and the two boxes are separated by the backboard 21 of the experimental box 1. In order to facilitate the staff to grasp the changes in data (temperature, humidity, charge, etc.) during the experiment, a display screen 6 is also provided on the backboard 21 that is in communication connection with the controller, which is used to display the experimental data in real time.

[0049] This embodiment also provides a method for detecting the electrostatic accumulation characteristics of powder, comprising the following steps:

[0050] (1) Select the material of the target chute 2, adjust the inclination angle of the chute 2 in the experimental chamber 1, and set the environmental temperature and humidity condition parameters;

[0051] (2) After the test environment is stable, perform a zeroing operation, add a certain mass of powder sample into the Faraday cup 42, and close the door panel 25 of the experimental chamber 1;

[0052] (3) After the initial charge Q1 and initial mass m1 readings of the powder sample are stable, the bidirectional rotation motor 43 operates to flip and pour the Faraday cup 42;

[0053] (4) After the powder sample is rubbed by the chute 2, it falls into the Faraday cylinder 3 through the hopper 5, and the static voltage V of the rubbed sample, the charge Q2 after falling, and the mass m2 parameter of the sample falling into the Faraday cylinder 3 are obtained;

[0054] (5) Clean the equipment with cotton dipped in ethyl acetate, ethanol or water;

[0055] (6) Repeat steps (1) to (5) for testing, repeat multiple times to obtain the average value of the static charge accumulation and static voltage, so as to reduce the test error;

[0056] (7) According to the test requirements, adjust the test conditions, repeat steps (1), (2), (3), (4), (5), (6), obtain the static charge accumulation and static voltage parameters of the powder sample under different test conditions, use software for data analysis, and fit the functions of environmental temperature, humidity, chute 2 angle, powder sample particle size, etc. with the static charge accumulation and static voltage of the powder sample, so as to realize the analysis of the influence law and parameter prediction of the static charge accumulation and static voltage of the powder under different conditions.

[0057] Illustrated with 2 specific examples:

[0058] Example 1: Test on the influence law of environmental temperature on the static charge accumulation and static voltage of TATB (triaminotrinitrobenzene) powder sample

[0059] (1) Select the chute 2 made of stainless steel, adjust the inclination angle of the chute 2 to 45°, set the environmental temperature to 30 °C, and the relative humidity to 40%;

[0060] (2) After the test environmental temperature and humidity are stable, perform a zeroing operation, add 5 g of TATB powder into the Faraday cup 42, and close the door panel 25 of the experimental chamber 1;

[0061] (3) After the initial charge Q1 and initial mass m1 readings of the powder sample are stable, the bidirectional rotation motor 43 operates to realize the flipping and pouring of the Faraday cup 42;

[0062] (4) After the powder sample is rubbed by the chute 2, it falls into the Faraday cylinder 3 through the aggregate hopper 5, and the static voltage V of the rubbed sample, the charge quantity Q2 after sliding down, and the mass m2 of the sample falling into the Faraday cylinder 3 are obtained;

[0063] (5) Clean the equipment with cotton dipped in ethyl acetate or ethanol;

[0064] (6) Repeat steps (1) to (5) for testing. Repeat multiple times (6 to 8 times) to obtain the average values of the static charge accumulation and the static voltage, so as to reduce the test error;

[0065] (7) According to the test requirements, adjust the ambient temperature to 20 °C, 25 °C, 30 °C, 35 °C, 40 °C. Repeat steps (1) to (6) to obtain the static charge accumulation and static voltage parameters of the TATB powder sample under different test conditions. Use software for data analysis, fit the function equations of the ambient temperature with the static charge accumulation and static voltage of the TATB powder sample, and realize the analysis of the influence law of the ambient temperature on the static charge accumulation and static voltage of the TATB powder sample, and the preliminary prediction of the static charge accumulation and static voltage parameters of the TATB powder sample at different temperatures.

[0066] (8) The test results are as Figure 6 shown, indicating that as the ambient temperature gradually increases from 20 °C to 40 °C, the static charge accumulation and static voltage of the TATB powder sample after being rubbed by the 45° stainless steel chute 2 both show a gradually increasing trend. This may be due to the change in the impurity migration rate of TATB and the change in the surface adsorbed water caused by the ambient temperature, thereby changing the resistivity of TATB and affecting the static charge accumulation and static voltage.

[0067] Example 2: Test on the influence law of ambient humidity on the static charge accumulation and static voltage of TATB

[0068] (1) Select the chute 2 made of stainless steel, adjust the inclination angle of the chute 2 to 45°, set the ambient temperature to 30 °C, and the relative humidity to 40%;

[0069] (2) After the ambient temperature and humidity of the test environment are stable, perform the zeroing operation, and add 5 g of TATB powder into the Faraday cup 42, and close the door panel 25 of the experimental box 1;

[0070] (3) After the initial charge quantity Q1 and the initial mass m1 of the powder sample are stable, the two-way rotating motor 43 operates to realize the tipping and discharging of the Faraday cup 42;

[0071] (4) After the powder sample is rubbed by the chute 2, it falls into the Faraday cylinder 3 through the aggregate hopper 5, and the static voltage V of the rubbed sample, the charge quantity Q2 after sliding down, and the mass m2 of the sample falling into the Faraday cylinder 3 are obtained;

[0072] (5) Clean the equipment with cotton dipped in ethyl acetate or ethanol;

[0073] (6) Repeat steps (1) to (5) for testing. Repeat multiple times to obtain the average values of the electrostatic accumulation amount and static voltage of the TATB powder sample, so as to reduce the test error;

[0074] (7) According to the test requirements, adjust the environmental humidity to 20%, 30%, 40%, 50%, 60%. Repeat steps (1) to (6) to obtain the electrostatic accumulation amount and static voltage parameters of the TATB powder sample under different test conditions. Use software for data analysis, fit the function equations of environmental humidity with the electrostatic accumulation amount and static voltage of the TATB powder sample, realize the analysis of the influence law of environmental humidity on the electrostatic accumulation amount and static voltage of the TATB powder sample, and the preliminary prediction of the electrostatic accumulation amount and static voltage parameters of the TATB powder sample at different temperatures.

[0075] (8) The test results are as Figure 7 shown, indicating that as the environmental humidity gradually increases from 20% to 60%, both the electrostatic accumulation amount and static voltage of TATB after being rubbed by the 45° stainless steel chute 2 show a gradually increasing trend. This may be because when the environmental humidity is relatively high, the number of water molecules adsorbed by the TATB powder increases, resulting in an increase in its surface conductivity, thereby enhancing the static charge leakage ability and greatly accelerating the attenuation rate of static charges, effectively restricting the electrostatic accumulation and the increase of static voltage of TATB.

[0076] Adaptations made according to actual needs are within the protection scope of the present invention.

[0077] Specific examples are used in the present invention to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A powder electrostatic accumulation characteristic detector, characterized in that: The invention comprises an experimental box and the following components arranged in the experimental box: The chute is used for the powder sample to slide down; A Faraday cup, the Faraday cup being located below the bottom end of the chute; A humidity regulating device, used for regulating the humidity in the experimental box; A temperature regulating device, used to regulate the temperature in the experimental box; and a feeding device, the feeding device comprising a lifting mechanism, a flip plate and a Faraday cup fixed on the flip plate, the end of the flip plate close to the top of the chute is hinged, the position of the flip plate away from the top of the chute is connected to the lifting mechanism, the lifting mechanism is used to flip the flip plate around the hinged end, the Faraday cup is used to hold the powder sample and pour the powder sample into the top of the chute when flipping.

2. The powder electrostatic accumulation characteristic detector according to claim 1, characterized in that: The lifting mechanism includes a fixed bidirectional rotating motor, a first connecting rod and a second connecting rod, the output end of the bidirectional rotating motor is fixedly connected to one end of the first connecting rod, the other end of the first connecting rod is hinged to one end of the second connecting rod, and the other end of the second connecting rod is hinged to the flip plate.

3. The powder electrostatic accumulation characteristic detector according to claim 2, characterized in that: The lifting mechanism also includes a fixed table, the flip plate and the lifting mechanism are both arranged on the fixed table, and a first weight sensor is also arranged on the fixed table. The first weight sensor is located at the bottom of the flip plate in an unflipped state and is used to obtain the mass of the powder sample in the Faraday cup.

4. The powder electrostatic accumulation characteristic detector according to claim 1, characterized in that: A metal drop tube connected to the Faraday cage is arranged below the bottom end of the slide groove, and the drop tube includes a straight pipe section and an annular raised section connected to each other, and the raised section has an annular accommodating cavity inside, and an insulating layer coplanar with the inner wall of the straight pipe section is arranged in the accommodating cavity, and an annular static voltage test electrode is arranged on the outer wall of the insulating layer.

5. The powder electrostatic accumulation characteristic detector according to claim 1, characterized in that: The humidity regulating device includes a humidification hole, a dehumidification pump and a circulating fan arranged in the experimental box, the humidification hole is connected to the humidifier, the dehumidification pump and the circulating fan are located on different walls in the experimental box, a first humidity sensor is arranged near the dehumidification pump, and a second humidity sensor is arranged near the circulating fan.

6. The powder static electricity accumulation characteristic detector according to claim 5, characterized in that: The temperature regulating device comprises a heater, a heat dissipation end of the heater is located inside the experimental box, and a temperature sensor is also arranged inside the experimental box.

7. The powder electrostatic accumulation characteristic detector according to claim 6, characterized in that: The heater includes a temperature-controlled water tank, a circulating water pump and a heat exchange tube. The heat exchange tube is located in the experimental box. Both ends of the heat exchange tube are connected to the temperature-controlled water tank through pipelines. The circulating water pump is located on the pipeline between the heat exchange tube and the temperature-controlled water tank.

8. The powder static electricity accumulation characteristic detector according to claim 1, characterized in that: An angle adjustment plate and an arc-shaped hole are also provided on the back plate of the experimental box, the slide groove is fixedly connected to the angle adjustment plate through a card slot, the top end of the angle adjustment plate is rotatably connected to the experimental box, and the bottom end of the angle adjustment plate is detachably connected to the position where the arc-shaped hole is located; the Faraday cup is arranged on an L-shaped plate, the vertical plate in the L-shaped plate is hinged to the bottom end of the angle adjustment plate, and the horizontal plate in the L-shaped plate is provided with a second weight sensor for weighing the Faraday cup.

9. The powder electrostatic accumulation characteristic detector according to claim 8, characterized in that: It also includes a connecting bolt, which passes through the vertical plate of the L-shaped plate, the angle adjustment plate and the arc-shaped hole on the back plate in sequence, and the end of the connecting bolt is connected with a locking nut.

10. The powder static electricity accumulation characteristic detector according to claim 1, characterized in that: The experimental box is provided with a door panel, and the door panel and the wall surface of the experimental box both include an electromagnetic shielding layer, a heat insulation layer and an electrostatic protection layer which are arranged in sequence from the inside to the outside.

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