A screw-type agitating and purging mixer for silicon nitride raw material and a mixing method thereof

Abstract

The present application relates to the technical field of silicon nitride preparation, in particular to a spiral stirring and blowing silicon nitride raw material mixer and a mixing method thereof, which comprises a support, a mixing barrel fixedly installed on the support, and a storage barrel fixed to the end of the mixing barrel; a hollow rod rotatably installed in the mixing barrel, a rotating sleeve fixed to the hollow rod; a plurality of air supply pipes fixed to the outer wall of the hollow rod and distributed at equal intervals in a circle, the air supply pipes being connected to the hollow rod, a synchronous feeding mechanism provided in the mixing barrel and connected to the air supply pipes and the hollow rod; a driving mechanism provided on the support and connected to the rotating sleeve; a rotating speed regulating assembly provided in the mixing barrel and connected to the driving mechanism and the rotating sleeve; a conduction regulating assembly provided on the mixing barrel and connected to the driving mechanism; and an angle adjusting mechanism provided in the mixing barrel and connected to the air supply pipes and the rotating speed regulating assembly.

Description

TECHNICAL FIELD

[0001] The application relates to a silicon nitride preparation technology field, in particular to a spiral stirring and blowing silicon nitride raw material mixer and a mixing method thereof. BACKGROUND

[0002] Silicon nitride is an important inorganic material, has high hardness, high wear resistance, high corrosion resistance, high temperature stability and other excellent performance, is widely used in electronic, photoelectric, chemical and other fields. This paper will introduce the production process of silicon nitride.

[0003] The production process of silicon nitride mainly includes raw material preparation, mixing, forming, sintering, processing and other links. In the raw material mixing, the main preparation methods include silicon powder direct nitriding method, carbon thermal reduction method, thermal decomposition method, sol-gel method, chemical vapor deposition and self-propagating method.

[0004] As for the self-propagating method, it is a synthesis technology which uses the heat released by chemical reaction as heat source to heat the adjacent reactants, so that the reaction can continue and conduct. The commonly used equipment is a self-propagating high temperature synthesis furnace. Taking a vacuum self-propagating high temperature synthesis device as an example, it mainly consists of a vacuum system, a vacuum chamber, a preheating furnace, a preheating furnace power supply, an ignition system, a mixing system, an ignition system power supply and an electrical control system. The vacuum system is composed of a mechanical pump, a diffusion pump or a molecular pump, a vacuum pipeline, a vacuum gate valve and an electromagnetic valve. Its characteristics are fast pumping speed and certain anti-pollution ability.

[0005] The preheating furnace is composed of five layers of metal heat shields and metal heating elements. Because of the small gas adsorption force, it can ensure the vacuum degree of the vacuum chamber and is suitable for vacuum environment. At the same time, it has good heat preservation effect, fast heating speed and high temperature.

[0006] The mixing system is mainly used for continuously mixing various reactants. For example, in the production process of pure aluminum titanium carbide, high-purity graphite powder and aluminum powder are mixed in a vacuum ball mill, and then loaded into a vacuum resistance sintering furnace for sintering to obtain a carbon aluminum alloy; after the titanium powder and the carbon aluminum alloy are ball milled with sodium nitrate in the vacuum ball mill, they are loaded into a vacuum self-propagating furnace, magnesium powder is added as an igniter, a tungsten wire is heated to ignite the magnesium powder, and a self-propagating reaction is carried out, and the furnace is naturally cooled down. Through the above process, the carbon aluminum alloy is first sintered from graphite powder and aluminum powder, and then the self-propagating reaction is completed from titanium powder and carbon aluminum alloy in one step; during the whole process, the graphite powder, aluminum powder and titanium powder need to be continuously mixed to realize the contact reaction between the substances.

[0007] The control system mainly includes a temperature control system, a vacuum safety alarm system and a mechanical action control system. The measurement and control scheme adopts hierarchical control management, which can automatically or semi-automatically complete a certain process according to the process route. It can monitor various parameters of the process, has reliable operation, stable mechanical action, simple and convenient operation and high control precision.

[0008] However, once the self-propagating reaction of silicon nitride synthesis starts, it basically does not need external energy, and the reaction continues to proceed until the reaction is completed; but in actual application, since the nitriding of silicon powder is an exothermic reaction, the existing self-propagating high-temperature synthesis furnace cannot adaptively adjust the reaction rate according to the temperature, which may cause the reaction temperature to be too high, resulting in molten silicon, which blocks the nitriding reaction, and also causes waste of raw materials. SUMMARY

[0009] The purpose of the present application is to provide a spiral stirring and blowing silicon nitride raw material mixer and a mixing method thereof to solve the problems raised in the background art.

[0010] To achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0011] A spiral stirring and blowing silicon nitride raw material mixer, comprising:

[0012] A support, a mixing barrel is fixedly installed on the support, and a storage barrel for placing silicon powder is fixedly installed at the end of the mixing barrel;

[0013] A hollow rod is rotatably installed in the mixing barrel, and a rotating sleeve is fixedly installed at the end of the hollow rod away from the mixing barrel, and the rotating sleeve penetrates the mixing barrel;

[0014] A plurality of gas supply pipes are fixedly installed on the outer wall of the hollow rod and are circumferentially equidistantly distributed, the gas supply pipes are in communication with the hollow rod, a synchronous feeding mechanism connected with the gas supply pipes and the hollow rod is arranged in the mixing barrel, the synchronous feeding mechanism can act when the rotating sleeve transports gas into the hollow rod, so as to control the conduction state of the gas supply pipes, and silicon powder in the storage barrel is transported into the mixing barrel through the synchronous feeding mechanism;

[0015] A driving mechanism is arranged on the support and connected with the rotating sleeve, the driving mechanism can drive the hollow rod to rotate through the rotating sleeve, so as to adjust the gas supply direction of the gas supply pipe;

[0016] characterized in that it further comprises:

[0017] A rotating speed regulating assembly is arranged in the mixing barrel and connected with the driving mechanism and the rotating sleeve, the rotating speed regulating assembly can act when the temperature in the mixing barrel changes, and the rotating speed of the rotating sleeve is adjusted through the driving mechanism;

[0018] A conduction regulating assembly is arranged on the mixing barrel and connected with the driving mechanism, the conduction regulating assembly can act when the rotating speed regulating assembly drives the driving mechanism to move, so as to adjust the conduction state of the rotating sleeve.

[0019] An angle adjusting mechanism is arranged in the mixing barrel and connected with the air feeding pipe and the rotating speed regulating assembly, and the angle adjusting mechanism can act when the hollow rod rotates and drive the air feeding pipe to reciprocate and swing in the vertical direction by a certain angle.

[0020] As a further scheme of the present application, the synchronous feeding mechanism comprises a first through groove arranged on the outer wall of the hollow rod, a movable rod movably arranged in the hollow rod and penetrating the mixing barrel and the storage barrel, a second through groove arranged on the circumferential side wall of the movable rod and matched with the first through groove, an elastic assembly arranged in the mixing barrel and connected with the movable rod and the hollow rod, and the movable rod is matched with the air feeding pipe.

[0021] As a further scheme of the present application, the elastic assembly comprises a conical block fixedly arranged in the movable rod, a limiting ring fixedly arranged on the movable rod, penetrating the first through groove and sleeved on the hollow rod, and a spring sleeved on the hollow rod and abutting against the limiting ring.

[0022] The elastic assembly comprises an inlet groove arranged on the circumferential side wall of the movable rod, and a sealing gasket fixedly arranged on one end of the movable rod and facing the storage barrel.

[0023] As a further scheme of the present application, the driving mechanism comprises a motor fixedly arranged on the support, a transmission rod rotatably arranged on the support and connected with the output shaft of the motor, a belt sleeved on the transmission rod, a rotating assembly arranged on the mixing barrel and connected with the belt, the rotating assembly is connected with the rotating sleeve, and the rotating assembly is also connected with the rotating speed regulating assembly and the conduction regulating assembly.

[0024] As a further scheme of the present application, the rotating assembly comprises a rotating disc fixedly arranged on the rotating sleeve, a plurality of sliding grooves circumferentially and equidistantly arranged on the rotating disc, a sliding rod slidably arranged in the sliding groove, an arc-shaped plate fixedly arranged on one end of the sliding rod and away from the sliding groove, the arc-shaped plate is connected with the belt, and the sliding rod is connected with the rotating speed regulating assembly and the conduction regulating assembly.

[0025] As a further scheme of the present application, the rotating speed regulating assembly comprises a heat conducting pipe fixedly arranged in the mixing barrel, a piston movably arranged in the heat conducting pipe and movably connected with the hollow rod, and a support rod fixedly arranged on the side wall of the piston and penetrating the mixing barrel.

[0026] The rotating speed regulating assembly comprises a movable disc fixedly installed on the rotating sleeve, a groove is formed in one end of the movable disc facing the mixing barrel, a plurality of first hinged rods are circumferentially and equidistantly distributed and hinged to one end of the movable disc away from the mixing barrel, the first hinged rods are hinged to the sliding rods, and the groove is in sliding connection with the supporting rods.

[0027] As a further scheme of the present application, the on-off regulating assembly comprises a hollow disc fixedly installed on one end of the rotating sleeve away from the mixing barrel, a plurality of supporting plates are fixedly installed on the side wall of the hollow disc and circumferentially and equidistantly distributed, a through on-off plate is slidingly installed in the supporting plates and penetrates through the hollow disc, and a second hinged rod is hinged to the on-off plate and hinged to the sliding rods.

[0028] As a further scheme of the present application, the angle adjusting mechanism comprises a supporting sleeve fixedly installed on the heat conducting pipe and sleeved on the hollow rod, a movable sleeve is movably installed in the supporting sleeve and movably connected to the hollow rod, a movable ring is movably installed on one end of the movable sleeve away from the supporting sleeve, a limiting assembly is arranged in the mixing barrel and connected to the movable ring and the movable sleeve, and the limiting assembly is connected to the hollow rod.

[0029] As a further scheme of the present application, the limiting assembly comprises a limiting groove formed in the inner wall of the supporting sleeve, a limiting rod is fixedly installed on the outer wall of the movable sleeve and engaged with the limiting groove, a plurality of connecting rods are circumferentially and equidistantly distributed and hinged to the movable ring, and the connecting rods are hinged to the air feeding pipe.

[0030] The limiting assembly further comprises guide grooves symmetrically formed in the outer wall of the hollow rod, and protrusions are fixedly installed on the inner wall of the movable sleeve and matched with the guide grooves.

[0031] A mixing method of a spiral stirring and blowing nitrogenized silicon raw material mixer, comprising the following steps:

[0032] Step one: the silicon powder required for the reaction is placed in the storage barrel, under the action of the synchronous feeding mechanism, the storage barrel is in a closed filling state, when the raw materials need to be mixed, at this time, nitrogen gas is fed into the rotating sleeve;

[0033] Step two: the nitrogen gas will enter the hollow rod, and under the action of the gas pressure, the synchronous feeding mechanism is controlled to move, so that the air feeding pipe is turned on, the nitrogen gas will enter the mixing barrel through the air feeding pipe, and under the action of the synchronous feeding mechanism, the silicon powder in the storage barrel is fed into the mixing barrel;

[0034] Step three: in order to ensure that the nitrogen and silicon powder reaction is more complete, under the action of the driving mechanism, rotating sleeve and hollow rod rotation, so that the nitrogen discharged through the gas pipe more evenly into the mixing bucket, and under the action of centrifugal force, so that the diffusion range of silicon powder is larger, to ensure that the contact area of silicon powder and nitrogen is larger, to ensure that the reaction is more thorough;

[0035] Step four: the driving mechanism will also control the angle adjusting mechanism movement through the hollow rod, to ensure that the gas pipe reciprocating deflection in the vertical direction a certain angle, to blow the silicon powder falling in the mixing bucket bottom, prevent the silicon powder deposition in the mixing bucket bottom;

[0036] Step five: because the reaction is exothermic reaction, if the temperature is too high will lead to silicon powder melting, therefore, need to control the reaction rate, under the action of temperature, the temperature control assembly movement, through the driving mechanism to reduce the rotating sleeve and hollow rod speed, at the same time, the driving mechanism will also drive the on-off control assembly movement, to reduce the rotating sleeve on-off area, so that the nitrogen and silicon powder delivery volume is reduced, thereby reducing the reaction rate.

[0037] Compared with the prior art, the beneficial effects of the present application are: when the raw materials need to be mixed, nitrogen can be delivered to the hollow rod through the rotating sleeve, under the action of gas pressure, control the synchronous feeding mechanism movement, so that the gas pipe is on, the nitrogen in the hollow rod will be delivered to the mixing bucket through the gas pipe, at the same time, under the action of the synchronous feeding mechanism, the silicon powder in the storage barrel is delivered to the mixing bucket and reacts with nitrogen, in order to ensure that the reaction is more comprehensive, at this time, the driving mechanism works, driving the rotating sleeve and hollow rod rotation, and under the action of the angle adjusting mechanism, control the gas pipe reciprocating swing a certain angle in the vertical direction, to blow the silicon powder in the mixing bucket, ensure that the reaction is more thorough, with the reaction, because the reaction is exothermic reaction, leading to the temperature increase in the mixing bucket, may lead to silicon powder melting, therefore, need to slow down the reaction rate, under the action of the rotating speed control assembly, drive the driving mechanism movement, so that the rotating sleeve and hollow rod speed is reduced, at the same time, under the action of the driving mechanism, control the on-off control assembly movement, so that the on-off area of the rotating sleeve is reduced, to reduce the nitrogen and silicon powder delivery volume, thereby achieving the purpose of slowing down the reaction rate. BRIEF DESCRIPTION OF DRAWINGS

[0038] Figure 1 Structure diagram of one embodiment of the spiral stirring and blowing silicon nitride raw material mixer.

[0039] Figure 2 Structure diagram of another angle in one embodiment of the spiral stirring and blowing silicon nitride raw material mixer.

[0040] Figure 3Schematic diagram of half section of one embodiment of the screw stirring and blowing silicon nitride raw material mixer.

[0041] Figure 4 Schematic diagram of half section of one embodiment of the screw stirring and blowing silicon nitride raw material mixer. Figure 3 Schematic diagram of half section of one embodiment of the screw stirring and blowing silicon nitride raw material mixer.

[0042] Figure 5 Schematic diagram of half section of one embodiment of the screw stirring and blowing silicon nitride raw material mixer.

[0043] Figure 6 Schematic diagram of half section of one embodiment of the screw stirring and blowing silicon nitride raw material mixer.

[0044] Figure 7 Schematic diagram of half section of one embodiment of the screw stirring and blowing silicon nitride raw material mixer.

[0045] Figure 8 Schematic diagram of half section of one embodiment of the screw stirring and blowing silicon nitride raw material mixer.

[0046] Figure 9 Schematic diagram of half section of one embodiment of the screw stirring and blowing silicon nitride raw material mixer.

[0047] Figure 10 Schematic diagram of half section of one embodiment of the screw stirring and blowing silicon nitride raw material mixer.

[0048] In the figure: 1, support; 2, mixing barrel; 3, storage barrel; 4, motor; 5, transmission rod; 6, belt; 7, rotating sleeve; 8, rotating disc; 9, sliding groove; 10, sliding rod; 11, arc plate; 12, hollow rod; 13, first through groove; 14, movable rod; 15, second through groove; 16, conical block; 17, limiting ring; 18, spring; 19, feeding slot; 20, sealing gasket; 21, heat conducting pipe; 22, support sleeve; 23, movable sleeve; 24, protrusion; 25, guide groove; 26, movable ring; 27, connecting rod; 28, gas feeding pipe; 29, piston; 30, support rod; 31, movable disc; 32, groove; 33, first hinged rod; 34, second hinged rod; 35, hollow disc; 36, support plate; 37, through plate. DETAILED DESCRIPTION

[0049] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described, obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0050] In addition, the elements in the present application are referred to as "fixed to" or "provided on" another element, which can be directly on another element or there can be a middle element. When an element is considered to be "connected" to another element, it can be directly connected to another element or there can be a middle element. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation.

[0051] Please refer to Figures 1-10 In the embodiments of the present application, a spiral stirring and blowing purging silicon nitride raw material mixer includes a support 1, a mixing barrel 2, a storage barrel 3, a hollow rod 12, a rotating sleeve 7, a gas feeding pipe 28, a synchronous feeding mechanism, a driving mechanism, a rotating speed control assembly, a conduction control assembly, an angle adjusting mechanism. Since the reaction is an exothermic reaction, it will cause the temperature of the mixing barrel 2 to increase. Under the action of the rotating speed control assembly and the conduction control assembly, the raw material delivery amount is reduced to slow down the reaction rate, so as to keep the temperature within a certain range. When the raw materials need to be mixed, nitrogen can be delivered into the hollow rod 12 through the rotating sleeve 7. Under the action of gas pressure, the synchronous feeding mechanism is controlled to move, so that the gas feeding pipe 28 is conducted. The nitrogen in the hollow rod 12 will be delivered into the mixing barrel 2 through the gas feeding pipe 28. At the same time, under the action of the synchronous feeding mechanism, the silicon powder in the storage barrel 3 is delivered into the mixing barrel 2 and reacts with the nitrogen. In order to ensure more comprehensive reaction, the driving mechanism works to drive the rotating sleeve 7 and the hollow rod 12 to rotate, and under the action of the angle adjusting mechanism, the gas feeding pipe 28 is controlled to reciprocate in the vertical direction by a certain angle, so as to blow the silicon powder in the mixing barrel 2, and ensure more thorough reaction. As the reaction proceeds, since the reaction is an exothermic reaction, the temperature in the mixing barrel 2 increases, which may cause the silicon powder to melt. Therefore, it is necessary to slow down the reaction rate. Under the action of the rotating speed control assembly, the driving mechanism is driven to move, so that the rotating speed of the rotating sleeve 7 and the hollow rod 12 is reduced. At the same time, under the action of the driving mechanism, the conduction control assembly is controlled to move, so that the conduction area of the rotating sleeve 7 is reduced, so as to reduce the delivery amount of nitrogen and silicon powder, thereby achieving the purpose of slowing down the reaction rate.

[0052] Specifically, it includes:

[0053] Support 1, a mixing barrel 2 is fixedly installed on the support 1, and a storage barrel 3 for placing silicon powder is fixedly installed at the end of the mixing barrel 2;

[0054] A hollow rod 12 is rotatably installed in the mixing barrel 2, and a rotating sleeve 7 is fixedly installed at the end of the hollow rod 12 away from the mixing barrel 2, and the rotating sleeve 7 penetrates the mixing barrel 2;

[0055] Please refer to Figures 1-3 、 Figures 5-8 A gas feeding pipe 28 is fixedly installed on the outer wall of the hollow rod 12 and is circumferentially equidistantly distributed, the gas feeding pipe 28 is connected with the hollow rod 12, a synchronous feeding mechanism connected with the gas feeding pipe 28 and the hollow rod 12 is arranged in the mixing barrel 2, the synchronous feeding mechanism can act when the rotating sleeve 7 transports gas into the hollow rod 12 to control the conduction state of the gas feeding pipe 28, and the synchronous feeding mechanism transports the silicon powder in the storage barrel 3 into the mixing barrel 2, the synchronous feeding mechanism includes a first through slot 13 opened in the outer wall of the hollow rod 12, a movable rod 14 penetrating the mixing barrel 2 and the storage barrel 3 is movably installed in the hollow rod 12, a second through slot 15 cooperating with the first through slot 13 is opened in the circumferential side wall of the movable rod 14, an elastic assembly connected with the movable rod 14 and the hollow rod 12 is arranged in the mixing barrel 2, and the movable rod 14 cooperates with the gas feeding pipe 28, wherein the elastic assembly includes a conical block 16 fixedly installed in the movable rod 14, a limiting ring 17 penetrating the first through slot 13 and sleeved on the hollow rod 12 is fixedly installed on the movable rod 14, and a spring 18 abutting against the limiting ring 17 is sleeved on the hollow rod 12; the elastic assembly includes an inlet slot 19 opened in the circumferential side wall of the movable rod 14, and a sealing gasket 20 is fixedly installed at the end of the movable rod 14 facing the storage barrel 3.

[0056] In detail, the mixing barrel 2 is provided with a heater for heating the mixing barrel 2. When preparing silicon nitride, the raw materials need to be mixed. In the initial state, the spring 18 is slightly compressed, the movable rod 14 is located at the end of the stroke towards the bottom of the mixing barrel 2, and the sealing gasket 20 abuts against the bottom of the storage barrel 3 to control the storage barrel 3 in the closed state, and the inlet chute 19 is located outside the storage barrel 3. Under the action of the movable rod 14, the gas feeding pipe 28 is in the closed state. When the raw materials need to be mixed, nitrogen can be introduced into the rotating sleeve 7 and fed into the hollow rod 12. Under the action of the gas pressure, the movable rod 14 is controlled to move towards the storage barrel 3, and the limiting ring 17 is driven to move, so that the spring 18 is compressed. At the same time, the movable rod 14 also drives the sealing gasket 20 to separate from the storage barrel 3, so that the inlet chute 19 enters the storage barrel 3. The silicon powder in the storage barrel 3 will enter the movable rod 14 and fall on the conical block 16. Under the action of the conical block 16, the silicon powder is discharged through the second through slot 15 and the first through slot 13 and uniformly dispersed in the mixing barrel 2. Under the action of the gas pressure, the movable rod 14 moves to the position separated from the gas feeding pipe 28, so that the nitrogen in the hollow rod 12 is fed into the mixing barrel 2 through the gas feeding pipe 28. Under the action of the heater, the temperature in the mixing barrel 2 reaches the required reaction temperature, so that the nitrogen and the silicon powder react.

[0057] Preferably, the mixing rate of the raw materials is related to the raw material conveying amount. If the nitrogen conveying amount increases, the pressure in the hollow rod 12 increases, the nitrogen discharge rate through the gas feeding pipe 28 increases, and the movement stroke of the movable rod 14 also increases with the increase of the pressure, so that the area of the inlet chute 19 entering the storage barrel 3 increases, thereby realizing the effect of synchronously adjusting the silicon powder conveying amount according to the nitrogen conveying amount.

[0058] Please refer to Figures 1-5 , Figures 8-10, drive mechanism, disposed on the support 1 and connected with the rotating sleeve 7, the drive mechanism can drive the hollow rod 12 to rotate through the rotating sleeve 7 to adjust the air feeding direction of the air feeding pipe 28, the drive mechanism comprises a motor 4 fixedly installed on the support 1, a transmission rod 5 connected with the output shaft of the motor 4 is rotatably installed on the support 1, a belt 6 is sleeved on the transmission rod 5, a rotating assembly connected with the belt 6 is arranged on the mixing barrel 2, the rotating assembly is connected with the rotating speed control assembly and the conduction control assembly, wherein the rotating assembly comprises a rotating disc 8 fixedly installed on the rotating sleeve 7, a plurality of slide grooves 9 distributed at equal intervals in a circle are formed in the rotating disc 8, a sliding rod 10 is slidably installed in the slide groove 9, an arc-shaped plate 11 is fixedly installed on the end of the sliding rod 10 away from the slide groove 9, the arc-shaped plate 11 is connected with the belt 6, and the sliding rod 10 is connected with the rotating speed control assembly and the conduction control assembly.

[0059] It should be noted that, in order to ensure that the nitrogen and the silicon powder react more comprehensively, it is necessary to control the nitrogen and the silicon powder to be more uniformly delivered into the mixing barrel 2, at this time, the motor 4 works to drive the transmission rod 5 to rotate, thereby driving the belt 6 to move, under the action of the belt 6, the arc-shaped plate 11 moves, thereby driving the rotating disc 8 provided with the slide grooves 9 to rotate through the sliding rod 10, the rotating disc 8 also drives the rotating sleeve 7 to move, thereby driving the hollow rod 12 to rotate, under the action of the centrifugal force, the silicon powder discharged through the first through slot 13 is uniformly dispersed in the mixing barrel 2, at the same time, the hollow rod 12 also drives the air feeding pipe 28 to rotate, so that the contact area between the nitrogen and the silicon powder discharged through the air feeding pipe 28 is increased, so as to ensure that the reaction is more thorough.

[0060] Preferably, the belt 6 has a certain elasticity and can be stretched or contracted to a certain extent, since the reaction is an exothermic reaction, the temperature in the mixing barrel 2 will increase as the reaction proceeds, if the reaction temperature is higher than a certain amount, the silicon powder will be melted, therefore, the reaction rate needs to be controlled according to the change of the temperature, when the temperature rises, under the action of the rotating speed control assembly, the sliding rod 10 moves along the length direction of the slide groove 9 and moves towards the direction away from each other, the sliding rod 10 also drives the arc-shaped plate 11 to move, so that the belt 6 is stretched, at this time, the belt 6 continues to move, the rotating speed of the rotating disc 8 is reduced, so that the contact area between the silicon powder and the nitrogen is reduced, thereby slowing down the reaction rate, so as to ensure that the temperature is maintained within a certain range.

[0061] Also includes:

[0062] Please refer to Figures 3-5 , Figure 8 , Figure 9, a rotating speed regulating assembly arranged in the mixing barrel 2 and connected with the driving mechanism and the rotating sleeve 7, the rotating speed regulating assembly being capable of acting when the temperature in the mixing barrel 2 changes and adjusting the rotating speed of the rotating sleeve 7 through the driving mechanism, the rotating speed regulating assembly comprising a heat-conducting pipe 21 fixedly installed in the mixing barrel 2, a piston 29 movably installed in the heat-conducting pipe 21 and movably connected with the hollow rod 12, and a support rod 30 fixed to the side wall of the piston 29 and penetrating through the mixing barrel 2; the rotating speed regulating assembly comprises a movable disc 31 fixedly installed on the rotating sleeve 7, one end of the movable disc 31 being provided with a groove 32 facing the mixing barrel 2, and a plurality of first hinged rods 33 circumferentially and equidistantly distributed and hinged to the movable disc 31 and away from the mixing barrel 2, the first hinged rods 33 being hinged with the sliding rod 10, and the groove 32 being slidably connected with the support rod 30.

[0063] Further, the nitriding reaction of the metal silicon powder is an exothermic reaction, if the heat cannot be released in time during the nitriding process, the nearby metal silicon powder will be melted, which seriously affects the nitriding reaction, therefore, with the nitriding reaction proceeding, the reaction rate needs to be adjusted according to the temperature change, the heat-conducting effect of the heat-conducting pipe 21 is good, and the heat-conducting pipe 21 is filled with gas, the gas can continuously shrink or expand according to the temperature change, when the temperature in the mixing barrel 2 increases, the gas in the heat-conducting pipe 21 will expand and control the movement of the piston 29, under the action of the piston 29, the movable disc 31 is controlled to move away from the mixing barrel 2 through the support rod 30, thereby driving the first hinged rods 33 to move, under the action of the first hinged rods 33, the sliding rod 10 is controlled to move along the length direction of the sliding groove 9 and move away from each other, so that the rotating speed of the rotating disc 8 is reduced, and the rotating speed of the rotating sleeve 7 is reduced, so as to reduce the reaction rate of the nitrogen and the silicon powder, thereby ensuring that the temperature in the mixing barrel 2 is within a certain range, wherein, when the rotating sleeve 7 rotates, the movable disc 31 will also rotate, and since the groove 32 is formed in the movable disc 31, the movement of the support rod 30 is ensured.

[0064] Please refer to Figures 3-5 , Figure 8 , Figure 10 , a conduction regulating assembly arranged on the mixing barrel 2 and connected with the driving mechanism, the conduction regulating assembly being capable of acting when the rotating speed regulating assembly drives the driving mechanism to move, so as to adjust the conduction state of the rotating sleeve 7, the conduction regulating assembly comprising a hollow disc 35 fixedly installed on the end of the rotating sleeve 7 away from the mixing barrel 2, a plurality of support plates 36 circumferentially and equidistantly distributed and fixed to the side wall of the hollow disc 35, a conduction plate 37 slidably installed in the support plates 36 and penetrating through the hollow disc 35, and a second hinged rod 34 hinged to the conduction plate 37 and hinged with the sliding rod 10.

[0065] Further, as the reaction proceeds, the temperature in the mixing barrel 2 is constantly increasing, so it is necessary to adjust the rate of the reaction. In the initial state, the temperature in the mixing barrel 2 is not high, and the spacing between the conductive plates 37 is maximum, so that the conductive area of the rotating sleeve 7 is maximum. When the temperature increases, it is necessary to reduce the delivery amount of nitrogen and silicon powder. At this time, the piston 29 moves, so that the sliding rod 10 moves towards the direction of moving away from each other, thereby driving the second articulated rod 34 to move, and the second articulated rod 34 also drives the conductive plate 37 to move along the length direction of the support plate 36, so that the spacing between the conductive plates 37 is reduced, thereby reducing the conductive area of the rotating sleeve 7, ensuring that the delivery amount of nitrogen is reduced. When the delivery amount of nitrogen is reduced, the pressure in the hollow rod 12 is reduced, so that the stroke amount of the movable rod 14 is reduced, so as to control the area of the inlet chute 19 entering the storage barrel 3 to be reduced, thereby synchronously reducing the delivery amount of nitrogen and silicon powder.

[0066] Please refer to Figures 3-6 、 Figure 8 , an angle adjusting mechanism arranged in the mixing barrel 2 and connected with the gas feeding pipe 28 and the rotating speed adjusting assembly, the angle adjusting mechanism can act when the hollow rod 12 rotates, and drive the gas feeding pipe 28 to reciprocatingly swing in the vertical direction by a certain angle. The angle adjusting mechanism comprises a support sleeve 22 fixedly installed on the heat conducting pipe 21 and sleeved on the hollow rod 12, an active sleeve 23 movably installed in the support sleeve 22 and movably connected with the hollow rod 12, and an active ring 26 movably installed at one end of the active sleeve 23 away from the support sleeve 22. A limiting assembly is arranged in the mixing barrel 2 and connected with the active ring 26 and the active sleeve 23, and the limiting assembly is connected with the hollow rod 12. The limiting assembly comprises a limiting groove opened in the inner wall of the support sleeve 22, a limiting rod fixedly installed on the outer wall of the active sleeve 23 and engaged with the limiting groove, a plurality of connecting rods 27 circumferentially and equidistantly hinged on the active ring 26, and the connecting rods 27 are hinged with the gas feeding pipe 28. The limiting assembly further comprises a guide groove 25 opened in the outer wall of the hollow rod 12 and symmetrically arranged, and a protrusion 24 fixedly installed on the inner wall of the active sleeve 23 and matched with the guide groove 25.

[0067] In detail, the air pipe 28 is made of metal hose material and can be inclined by a certain angle. When the silicon powder is added into the mixing barrel 2, the silicon powder will fall to the bottom of the mixing barrel 2. In order to ensure that the reaction of the silicon powder is more complete, the silicon powder at the bottom needs to be swept, and therefore the air angle of the air pipe 28 needs to be adjusted. When the hollow rod 12 rotates, the guide groove 25 is driven to move. The guide groove 25 is spirally arranged. Under the action of the guide groove 25, the movable sleeve 23 fixed with the protrusion 24 moves. Since the limiting rod is engaged with the limiting groove, the movable sleeve 23 can only move along the length direction of the supporting sleeve 22 and cannot rotate with the hollow rod 12. The movable sleeve 23 also drives the movable ring 26 to move and drives the air pipe 28 to swing away from the supporting sleeve 22 through the connecting rod 27. When the protrusion 24 moves to the end of the stroke on one side of the guide groove 25, the movable sleeve 23 moves to the end of the stroke away from the supporting sleeve 22 and moves toward the supporting sleeve 22 under the action of the guide groove 25 to control the air pipe 28 to swing toward the supporting sleeve 22. The above steps are repeated to increase the air supply range of the air pipe 28 and sweep the silicon powder at the bottom of the mixing barrel 2, so that the reaction of the silicon powder is more complete.

[0068] Preferably, when the temperature in the mixing barrel 2 increases, the rotating speed of the hollow rod 12 decreases, so that the movement speed of the movable sleeve 23 decreases, thereby slowing down the swinging speed of the air pipe 28 to further reduce the reaction speed.

[0069] A mixing method of a spiral stirring and sweeping silicon nitride raw material mixer, comprising the following steps:

[0070] Step one: place the silicon powder required for the reaction into the storage barrel 3. Under the action of the synchronous feeding mechanism, the storage barrel 3 is in a sealed filling state. When the raw materials need to be mixed, nitrogen gas is supplied into the rotating sleeve 7 at this time;

[0071] Step two: the nitrogen gas will enter the hollow rod 12 and control the movement of the synchronous feeding mechanism under the action of the gas pressure, so that the air pipe 28 is conducted. The nitrogen gas will enter the mixing barrel 2 through the air pipe 28, and at the same time, the silicon powder in the storage barrel 3 is fed into the mixing barrel 2 under the action of the synchronous feeding mechanism;

[0072] Step three: in order to ensure that the reaction of the nitrogen gas and the silicon powder is more complete, the rotating sleeve 7 and the hollow rod 12 are driven to rotate under the action of the driving mechanism, so that the nitrogen gas discharged through the air pipe 28 enters the mixing barrel 2 more uniformly, and under the action of the centrifugal force, the diffusion range of the silicon powder is larger, so as to ensure that the contact area of the silicon powder and the nitrogen gas is larger and the reaction is more thorough;

[0073] Step four: the driving mechanism also controls the angle adjusting mechanism to move through the hollow rod 12 to ensure that the gas pipe 28 rotates and reciprocates in the vertical direction to sweep the silicon powder falling on the bottom of the mixing barrel 2, preventing the silicon powder from depositing on the bottom of the mixing barrel 2;

[0074] Step five: since the reaction is an exothermic reaction, if the temperature is too high, the silicon powder will melt, therefore, the reaction rate needs to be controlled, under the action of temperature, the temperature regulating assembly moves to reduce the rotating speed of the rotating sleeve 7 and the hollow rod 12 through the driving mechanism, at the same time, the driving mechanism also drives the conduction regulating assembly to move to reduce the conduction area of the rotating sleeve 7, so that the delivery amount of nitrogen gas and silicon powder is reduced, thereby reducing the reaction rate.

[0075] It is apparent to those skilled in the art that the present application is not limited to the details of the foregoing exemplary embodiments, and that the present application can be implemented in other particular forms without departing from the spirit or essential characteristics of the present application. Therefore, the embodiments should be considered in all respects as illustrative and not restrictive, the scope of the present application being indicated by the appended claims rather than by the foregoing description, and it is intended that all changes and modifications which come within the meaning and range of equivalency of the claims are resolvable thereunder. Any reference signs in the claims should not be construed as limiting the claims to the figures in which the reference signs are used.

[0076] In addition, it should be understood that although the present specification is described in terms of embodiments, not every embodiment contains only one independent technical solution, and the description of the specification is only for the sake of clarity, and those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be appropriately combined to form other embodiments that those skilled in the art can understand.

Claims

1. A spiral tumbling and blowing silicon nitride raw material mixer, comprising: A mixing tank (2) is provided with a storage tank (3) for placing silicon powder at one end. Hollow rod (12) is rotatably installed inside mixing barrel (2). A rotating sleeve (7) is fixed at the end of hollow rod (12) away from mixing barrel (2). The rotating sleeve (7) passes through mixing barrel (2). An air supply pipe (28) is fixedly installed on the outer wall of the hollow rod (12) and there are multiple pipes distributed equidistantly in a circle. The air supply pipe (28) is connected to the hollow rod (12). A synchronous feeding mechanism connected to the air supply pipe (28) and the hollow rod (12) is provided in the mixing tank (2). The drive mechanism is mounted on the bracket (1) and connected to the rotating sleeve (7); Its characteristic is that it further includes: The speed control component is installed inside the mixing tank (2) and connected to the drive mechanism and the rotating sleeve (7). The speed control component can operate when the temperature inside the mixing tank (2) changes, and adjust the speed of the rotating sleeve (7) through the drive mechanism. The conduction control component is set on the mixing tank (2) and connected to the drive mechanism. The conduction control component can be activated when the speed control component drives the drive mechanism to move, so as to adjust the conduction state of the rotating sleeve (7). An angle adjustment mechanism is set inside the mixing tank (2) and connected to the air supply pipe (28) and the speed control component. The angle adjustment mechanism can operate when the hollow rod (12) rotates, and drive the air supply pipe (28) to swing back and forth at a certain angle in the vertical direction. The drive mechanism includes a motor (4) fixedly mounted on the bracket (1), a transmission rod (5) rotatably mounted on the bracket (1) and connected to the output shaft of the motor (4), a belt (6) sleeved on the transmission rod (5), a rotating assembly connected to the belt (6) on the mixing tank (2), the rotating assembly being connected to the rotating sleeve (7), and the rotating assembly also being connected to the speed control assembly and the conduction control assembly; The rotating assembly includes a turntable (8) fixedly mounted on the rotating sleeve (7). The turntable (8) has multiple grooves (9) evenly distributed around the circumference. A sliding rod (10) is slidably mounted in the groove (9). An arc plate (11) is fixed to one end of the sliding rod (10) away from the groove (9). The arc plate (11) is connected to the belt (6). The sliding rod (10) is connected to the speed control assembly and the conduction control assembly. The speed control component includes a heat-conducting pipe (21) fixedly installed inside the mixing tank (2), a piston (29) movably installed inside the heat-conducting pipe (21) and movably connected to the hollow rod (12), and a support rod (30) symmetrically arranged and penetrating the mixing tank (2) fixed on the side wall of the piston (29). The speed control component includes a movable disc (31) fixedly installed on the rotating sleeve (7). The movable disc (31) has a groove (32) at one end facing the mixing tank (2). The movable disc (31) away from the mixing tank (2) is hinged to a plurality of first hinge rods (33) distributed equidistantly in a circle. The first hinge rod (33) is hinged to the sliding rod (10). The groove (32) is slidably connected to the support rod (30).

2. The silicon nitride raw material mixer with spiral stirring and blowing according to claim 1, characterized in that, The synchronous feeding mechanism includes a first through groove (13) opened on the outer wall of the hollow rod (12), a movable rod (14) movably installed inside the hollow rod (12) and passing through the mixing tank (2) and the storage tank (3), a second through groove (15) that cooperates with the first through groove (13) is opened on the circumferential side wall of the movable rod (14), an elastic component that connects to the movable rod (14) and the hollow rod (12) is provided inside the mixing tank (2), and the movable rod (14) cooperates with the air supply pipe (28).

3. The silicon nitride raw material mixer with spiral stirring and blowing according to claim 2, characterized in that, The elastic component includes a conical block (16) fixedly installed in the movable rod (14), a limiting ring (17) that passes through the first through slot (13) and is sleeved on the hollow rod (12) is fixed on the movable rod (14), and a spring (18) that abuts against the limiting ring (17) is sleeved on the hollow rod (12). The elastic component includes a feed groove (19) formed on the circumferential sidewall of the movable rod (14), and a sealing gasket (20) is fixed to one end of the movable rod (14) facing the storage tank (3).

4. The silicon nitride raw material mixer with spiral stirring and blowing according to claim 1, characterized in that, The conduction control assembly includes a hollow disk (35) fixedly installed on the end of the rotating sleeve (7) away from the mixing tank (2). The side wall of the hollow disk (35) is fixed with a plurality of support plates (36) distributed equidistantly in a circle. A conduction plate (37) penetrating the hollow disk (35) is slidably installed inside the support plate (36). A second hinge rod (34) hinged to the sliding rod (10) is hinged on the conduction plate (37).

5. The silicon nitride raw material mixer with spiral stirring and blowing according to claim 1, characterized in that, The angle adjustment mechanism includes a support sleeve (22) fixedly installed on the heat-conducting pipe (21) and sleeved on the hollow rod (12). A movable sleeve (23) movably connected to the hollow rod (12) is movably installed inside the support sleeve (22). A movable ring (26) is movably installed at one end of the movable sleeve (23) away from the support sleeve (22). A limiting component connected to the movable ring (26) and the movable sleeve (23) is provided inside the mixing tank (2). The limiting component is connected to the hollow rod (12).

6. The silicon nitride raw material mixer with spiral stirring and blowing according to claim 5, characterized in that, The limiting component includes a limiting groove formed on the inner wall of the support sleeve (22), a limiting rod fixed on the outer wall of the movable sleeve (23) that engages with the limiting groove, and a plurality of connecting rods (27) that are circumferentially distributed are hinged on the movable ring (26), and the connecting rods (27) are hinged to the air supply pipe (28). The limiting component also includes guide grooves (25) formed on the outer wall of the hollow rod (12) and arranged symmetrically, and the inner wall of the movable sleeve (23) is fixed with protrusions (24) that cooperate with the guide grooves (25).

7. A mixing method using a spiral agitation and blowing silicon nitride raw material mixer, comprising the spiral agitation and blowing silicon nitride raw material mixer as described in any one of claims 1-6, characterized in that, Includes the following steps: Step 1: Place the silicon powder required for the reaction into the storage tank (3). Under the action of the synchronous feeding mechanism, the storage tank (3) is in a sealed state. When it is necessary to mix the raw materials, nitrogen gas is supplied into the rotating sleeve (7). Step 2: Nitrogen gas will enter the hollow rod (12) and, under the action of gas pressure, control the movement of the synchronous feeding mechanism, so that the gas supply pipe (28) is open and the nitrogen gas will enter the mixing tank (2) through the gas supply pipe (28). At the same time, under the action of the synchronous feeding mechanism, the silicon powder in the storage tank (3) will be transported to the mixing tank (2). Step 3: In order to ensure that the reaction between nitrogen and silicon powder is more complete, the rotating sleeve (7) and hollow rod (12) are driven to rotate under the action of the driving mechanism, so that the nitrogen discharged through the gas supply pipe (28) enters the mixing tank (2) more evenly, and under the action of centrifugal force, the diffusion range of silicon powder is larger, so as to ensure that the contact surface between silicon powder and nitrogen is larger and the reaction is more thorough. Step 4: The drive mechanism will also control the movement of the angle adjustment mechanism through the hollow rod (12) to ensure that the air supply pipe (28) rotates while swinging back and forth at a certain angle in the vertical direction, so as to blow away the silicon powder falling to the bottom of the mixing barrel (2) and prevent the silicon powder from depositing at the bottom of the mixing barrel (2). Step 5: Since the reaction is exothermic, if the temperature is too high, the silicon powder will melt. Therefore, it is necessary to control the reaction rate. Under the influence of temperature, the rotation speed control component moves to reduce the rotation speed of the rotating sleeve (7) and the hollow rod (12) through the drive mechanism. At the same time, the drive mechanism will also drive the conduction control component to move to reduce the conduction area of ​​the rotating sleeve (7), thereby reducing the amount of nitrogen and silicon powder transported, and thus reducing the reaction rate.

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