An ultrafine grinder

Abstract

The application discloses an ultrafine pulverizer, which comprises a pulverizer body and a cyclone separator, wherein the pulverizer body comprises a pulverizing cavity, a gear ring, an impeller and a powder selecting cavity; a driving shaft is arranged on the central axis of the pulverizing cavity, the impeller is fixed on the driving shaft, and the gear ring is fixed on the side wall of the pulverizing cavity; the powder selecting cavity is in a cylindrical structure, the lower end of the powder selecting cavity is connected with the pulverizing cavity, and the upper end face of the powder selecting cavity is closed; the application is suitable for the technical field of the pulverizer, simplifies the structure of the pulverizer, occupies a small space, is easy to maintain, has small material loss caused by pipeline adhesion, can realize the technical effect of energy saving and consumption reduction, does not need to carry out secondary material collection, thereby reducing the pollution risk, and further reduces the pollution risk without a large terminal bag filter, thereby avoiding the difficulty caused by a large number of bag cleaning and replacement.

Description

Technical Field

[0001] This invention belongs to the field of pulverizer technology, specifically an ultrafine pulverizer. Background Technology

[0002] During operation, the material enters the grinding chamber of a pulverizer, forming a pulverized mixture containing fine powder, coarse powder, and large particles of different sizes. At this point, it is necessary to separate the fine powder that meets the required fineness, while the coarse powder and particles that do not meet the fineness requirements remain in the grinding chamber for further pulverization. This process is called "powder selection" or "grading." Generally speaking, fine powder below 120 mesh can be selected using a mesh screen, while for fine powder above 120 mesh, the most common technique is to use a classifying wheel for powder selection.

[0003] However, the use of classifying wheel technology for powder selection in the ultrafine grinding process has the following main drawbacks:

[0004] First, whether it is an internal grading wheel or an external grading and classifying machine, an independent drive mechanism is required for the grading wheel, which will result in a complex structure of the entire pulverizer unit and a high equipment investment cost.

[0005] Second, existing ultrafine pulverizer units require a large exhaust duct and exhaust filtration system after the classifier wheel, which takes up a lot of space, is difficult to operate and maintain, and has a large process loss.

[0006] Third, existing ultrafine pulverizer units require multiple power sources such as pulverizing motors, classifying motors, and exhaust fans. Moreover, the exhaust power needs to overcome the resistance of the classifying wheel and the filter, resulting in a large exhaust power. At the same time, the terminal bag filter also needs to be equipped with a back-flushing air compressor, so the entire system consumes a lot of energy.

[0007] Fourth, the risk of contamination is high. Existing ultrafine pulverizers require product to be collected from two or even three places, namely the cyclone separator and the filter bag, which is inconvenient to operate. In addition, the filter bag is difficult to clean and replace, so the product is at high risk of contamination. Summary of the Invention

[0008] The purpose of this invention is to overcome the shortcomings of the prior art and provide an ultrafine pulverizer.

[0009] To achieve the above objectives, the present invention adopts the following technical solution:

[0010] An ultrafine pulverizer includes: a pulverizer body and a cyclone separator, wherein the pulverizer body includes a pulverizing chamber, a toothed ring, an impeller, and a powder selection chamber;

[0011] A drive shaft is provided on the central axis of the crushing chamber, the impeller is fixed on the drive shaft, and the gear ring is fixed on the side wall of the crushing chamber.

[0012] The powder selection chamber has a cylindrical structure, with its lower end connected to the crushing chamber and its upper end face closed.

[0013] A central tube is provided on the central axis of the powder classifying chamber. The upper end of the central tube passes through the upper end face of the powder classifying chamber, and the lower end of the central tube opens into the area near the center of the impeller.

[0014] The upper part of the central tube is provided with a feed inlet and an air return outlet;

[0015] The upper end face of the powder selection chamber is provided with a discharge port, which is connected to the air inlet of the cyclone separator through a discharge pipe, and the air return port is connected to the air outlet of the cyclone separator through an air return pipe.

[0016] Preferably, a plurality of coarse powder outlets are provided on the upper end face or side wall of the powder selection chamber, and a coarse powder return port is provided on the upper part of the central tube. The coarse powder outlets and the coarse powder return port are connected through a coarse powder return pipe.

[0017] Preferably, the upper end face of the powder selection chamber has a conical structure or a multi-stage conical structure.

[0018] Preferably, the upper end face of the powder selection chamber has a hemispherical or semi-ellipsoidal structure.

[0019] Preferably, the central tube has a circular structure, the diameter of the feed inlet is smaller than the diameter of the upper end of the central tube, and the feed inlet is located at the center of the upper end of the central tube.

[0020] Preferably, a hopper is connected above the feed inlet.

[0021] Preferably, it also includes an exhaust filter;

[0022] The exhaust filter is provided with an exhaust filter inlet, an exhaust filter return inlet, and an exhaust filter outlet, with the exhaust filter return inlet located at the bottom of the exhaust filter;

[0023] The air inlet and air return outlet of the exhaust filter are located on the same side of the filter material.

[0024] The air return pipe is divided into a front section and a rear section.

[0025] The cyclone separator outlet, the front section of the air return pipe, the exhaust filter inlet, the exhaust filter, the exhaust filter return inlet, the rear section of the air return pipe, and the air return port are connected in sequence.

[0026] Preferably, the filter material of the exhaust filter is a soft cloth bag, with one open end fitted onto the end of the exhaust port of the exhaust filter, so that the airflow is discharged from the inside to the outside.

[0027] Preferably, the air return pipe is divided into a front section and a rear section; the front section and the rear section are connected by a soft cloth bag.

[0028] Preferably, the outer walls of the crushing chamber and the powder sorting chamber are provided with cooling jackets, and the cooling jackets are provided with cooling water inlets and cooling water outlets.

[0029] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0030] In this invention, an internal circulating airflow drives the pulverized mixture to rotate along the inner wall of the powder-selection chamber. Only powders with smaller particle sizes can reach the outlet, while larger powders flow back into the pulverization chamber for further pulverization. This principle eliminates the need for a classifying wheel, thus avoiding a series of problems associated with classifying wheels and simplifying the internal structure of the pulverizer.

[0031] In this invention, most of the airflow circulates inside the pulverizer, with only a very small amount of airflow being discharged to the outside. It does not require a large exhaust duct system and exhaust filtration system, thus occupying little space, simplifying operation and maintenance, and minimizing material loss due to pipe adhesion.

[0032] In this invention, the pulverizing impeller simultaneously provides pulverizing power, airflow circulation power, and exhaust power; at the same time, because the exhaust air volume is small and the filtration area is small, there is no need to continuously use compressed air to backflush and clean the filter bag, thereby achieving the technical effect of energy saving and consumption reduction.

[0033] In this invention, all the pulverized fine powder is concentrated in the cyclone separator, and a small amount of unseparated fine powder flows back into the pulverizer. Therefore, secondary material collection is not required, thereby reducing the risk of contamination. In addition, a large terminal bag filter is not required, avoiding the difficulties caused by cleaning and replacing a large number of bags, further reducing the risk of contamination. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the overall structure of an ultrafine pulverizer according to the present invention. Figure 1 ;

[0035] Figure 2 This is a schematic diagram of the overall structure of an ultrafine pulverizer according to the present invention. Figure 2 ;

[0036] Figure 3 This is a schematic diagram of the overall structure of an ultrafine pulverizer according to the present invention. Figure 3 ;

[0037] Figure 4 This is a schematic diagram of the overall structure of an ultrafine pulverizer according to the present invention. Figure 4 .

[0038] Figure label:

[0039] 01. Crusher body;

[0040] 011. Crushing chamber; 012. Gear ring; 013. Drive shaft; 014. Impeller; 015. Classifying chamber; 016. Upper end face of classifying chamber; 017. Central tube; 018. Feed inlet; 019. Air return port; 0110. Discharge port; 0111. Discharge pipe; 0112. Front section of air return pipe; 0113. Rear section of air return pipe; 0114. Side wall of classifying chamber; 0115. Coarse powder outlet; 0116. Coarse powder return port; 0117. Coarse powder return pipe; 0118. Hopper; 0119. Cooling jacket; 0120. Cooling water inlet; 0121. Cooling water outlet; 0122. Air return pipe;

[0041] 02. Cyclone separator;

[0042] 021. Cyclone separator air inlet; 022. Cyclone separator air outlet; 023. Material collection container;

[0043] 03. Exhaust air filter;

[0044] 031. Air inlet of exhaust filter; 032. Air return outlet of exhaust filter; 033. Soft cloth bag; 034. Air outlet of exhaust filter. Detailed Implementation

[0045] The following is in conjunction with the appendix Figure 1-4 The following further illustrates specific embodiments of the ultrafine pulverizer of the present invention. The ultrafine pulverizer of the present invention is not limited to the descriptions in the following embodiments.

[0046] Example 1:

[0047] This embodiment provides a specific implementation method for an ultrafine pulverizer, such as... Figure 1-4 As shown, it includes: a pulverizer body 01 and a cyclone separator 02. The pulverizer body 01 includes a pulverizing chamber 011, a gear ring 012, an impeller 014 and a powder selection chamber 015.

[0048] A drive shaft 013 is provided on the central axis of the crushing chamber 011, an impeller 014 is fixed on the drive shaft 013, and a gear ring 012 is fixed on the side wall of the crushing chamber 011.

[0049] The powder selection chamber 015 has a cylindrical structure, and its lower end is connected to the crushing chamber 011. The upper end face 016 of the powder selection chamber is closed.

[0050] A central tube 017 is provided on the central axis of the powder classifying chamber 015. The upper end of the central tube 017 passes through the upper end face 016 of the powder classifying chamber, and the lower end of the central tube 017 opens into the area near the center of the impeller 014.

[0051] The upper part of the central tube 017 is provided with a feed inlet 018 and an air return outlet 019;

[0052] The upper end face 016 of the powder selection chamber is provided with a discharge port 0110. The discharge port 0110 is connected to the air inlet 021 of the cyclone separator through the discharge pipe 0111. The air return port 019 is connected to the air outlet 022 of the cyclone separator through the air return pipe 0122.

[0053] Furthermore, depending on the process and output, a material collection container 023, a control valve, an electric unloading valve, and other mechanisms can be connected below the cyclone separator.

[0054] By adopting the above technical solution:

[0055] The pulverizing impeller rotates at high speed in the pulverizing chamber 011, driving the air in the pulverizing chamber 011 to rotate at high speed, forming a spiral airflow, which spirals upward along the inner wall of the pulverizing chamber 011.

[0056] The material is added through the feed inlet 018 and flows downward into the crushing chamber 011 along the central tube 017. It is accelerated by the crushing impeller and collides and shears with the surrounding toothed ring 012 to form a crushed mixture.

[0057] The pulverized mixture is carried upward by the spiral airflow and enters the powder classifier 015. The diameter of the upper end face 016 of the powder classifier decreases. In the pulverized mixture, the larger the particle size of the powder, the greater the centrifugal force it experiences, and it cannot move to the upper part of the powder classifier 015. Only the finer powder can move to the upper discharge port 0110 of the powder classifier 015.

[0058] The spiral airflow pressure on the outer ring of the powder selection chamber 015 is relatively high, while the pressure at the bottom of the central tube 017, which is close to the center of the impeller 014, is relatively low, thus forming a pressure gradient.

[0059] Under the action of the pressure gradient, the fine powder flows into the cyclone separator 02 along the discharge pipe 0111 with the airflow and is separated and flows into the collection container 023. A small amount of fine powder that is not separated flows back into the crushing chamber 011 along the air return pipe and enters the next cycle.

[0060] Larger coarse powder and large particles remain in the powder selection chamber and continue to rotate, then fall back into the crushing chamber 011 for further crushing.

[0061] Example 2:

[0062] This embodiment provides a specific implementation method for an ultrafine pulverizer, such as... Figure 1-4 As shown, the other structures are similar to those in Embodiment 1. Several coarse powder outlets 0115 are provided on the upper end face 016 of the powder selection chamber or the side wall 0114 of the powder selection chamber. A coarse powder return port 0116 is provided on the upper part of the central tube 017. The coarse powder outlets 0115 and the coarse powder return port 0116 are connected through the coarse powder return pipe 0117.

[0063] By adopting the above technical solution:

[0064] A pressure gradient also exists between the coarse powder outlet 0115 and the central pipe 017. Under the action of the pressure gradient, coarse powder with a larger particle size and large particles can flow back to the center of the impeller 014 along the coarse powder outlet 0115, coarse powder return pipe 0117, coarse powder return port 0116, and central pipe 017. This return method can effectively improve the efficiency of coarse powder return crushing.

[0065] Example 3:

[0066] This embodiment provides a specific implementation method for an ultrafine pulverizer, such as... Figure 1-2 As shown, the other structures are similar to those in Example 1, with the upper end face 016 of the powder selection chamber being a conical structure or a multi-stage conical structure.

[0067] Example 4:

[0068] This embodiment provides a specific implementation method for an ultrafine pulverizer, such as... Figure 3-4 As shown, the other structures are similar to those in Example 1, except that the upper end face 016 of the powder selection cavity is a hemispherical or semi-ellipsoidal structure.

[0069] By adopting the above technical solution:

[0070] Further refinement of the shape of the upper end face 016 of the powder classifier cavity, these different shapes of upper end faces are beneficial to improving the powder classifier accuracy.

[0071] Example 5:

[0072] This embodiment provides a specific implementation method for an ultrafine pulverizer, such as... Figure 1-4 As shown, the other structures are similar to those in Embodiment 1. The central tube 017 is a circular structure, and the diameter of the feed inlet 018 is smaller than the diameter of the upper end of the central tube 017. The feed inlet 018 is located at the center of the upper end of the central tube 017.

[0073] By adopting the above technical solution:

[0074] Inside the central tube 017, the air pressure is lower closer to the center. The feed inlet 018 is located at the center of the upper end of the central tube 017, which can ensure that the feed inlet is in a negative pressure state, effectively preventing dust in the central tube 017 from overflowing upward from the feed inlet 018. At the same time, it is conducive to forming a downward suction force, promoting the material to flow into the central tube 017.

[0075] Example 6:

[0076] This embodiment provides a specific implementation method for an ultrafine pulverizer, such as... Figure 1-4 As shown, the other structures are similar to those in Embodiment 1, with a hopper 0118 connected above the feed inlet 018.

[0077] Example 7:

[0078] This embodiment provides a specific implementation method for an ultrafine pulverizer, such as... Figure 2-3 As shown, the other structures are similar to those in Embodiment 1, and also include an exhaust filter 03;

[0079] The exhaust filter 03 is provided with an exhaust filter inlet 031, an exhaust filter return air outlet 032, and an exhaust filter outlet 034. The exhaust filter return air outlet 032 is located at the bottom of the exhaust filter.

[0080] The exhaust filter inlet 031 and the exhaust filter return air outlet 032 are located on the same side of the filter material.

[0081] The air return pipe 0122 is divided into the front section 0112 and the rear section 0113.

[0082] The cyclone separator outlet 022, the front section of the air return pipe 0112, the exhaust filter inlet 031, the exhaust filter 03, the exhaust filter return port 032, the rear section of the air return pipe 0113, and the air return port 019 are connected in sequence.

[0083] By adopting the above technical solution:

[0084] The exhaust filter 03 is installed to discharge some air during operation, which can ensure that the entire crusher works under negative pressure and prevent dust from overflowing from the feed port 018; at the same time, the exhaust helps to reduce the temperature inside the crushing chamber 011.

[0085] The dust trapped by the exhaust filter 03 during operation falls to the bottom of the exhaust filter 03 and flows into the crushing chamber 011 along the air return port 032, the rear section of the air return pipe 0113, the air return port 019, and the central pipe 017. Therefore, the fine powder in the exhaust filter 03 does not need to be collected separately.

[0086] Depending on specific process requirements, back-blowing, rapping, and other dust removal mechanisms can be added to the exhaust filter 03 to clean the fine powder accumulated on the surface of the filter media and ensure filtration efficiency.

[0087] The exhaust filter 03 used in this invention only discharges a small portion of the air in the system's circulating airflow, so the overall exhaust volume is small and the filter area is small. The fine powder trapped inside the filter can automatically flow back, and even if the exhaust filter 03 is clogged, it will not have a significant impact on the normal operation of the pulverizer.

[0088] Example 8:

[0089] This embodiment provides a specific implementation method for an ultrafine pulverizer, such as... Figure 3 As shown, the other structures are similar to those in Embodiment 7. The filter material of the exhaust filter 03 is a soft cloth bag 033, one end of which is sleeved on the end of the exhaust port 034 of the exhaust filter, and the airflow is discharged from the inside to the outside.

[0090] By adopting the above technical solution:

[0091] The exhaust filter 03 uses a soft cloth bag 033, which is directly connected to the exhaust port 034 of the exhaust filter. The filter is inflated by positive pressure in the pipeline, eliminating the need for an internal frame. This filtration method has a simple structure, trapping fine powder on the inner surface of the soft cloth bag 033, making cleaning and disassembly convenient. In a small ultrafine pulverizer, manually tapping the outer surface of the soft cloth bag 033 will dislodge the fine powder adhering to its inner surface, which will then be carried back to the pulverizer by the airflow.

[0092] Example 9:

[0093] This embodiment provides a specific implementation method for an ultrafine pulverizer, such as... Figure 4 As shown, the other structures are similar to those in Embodiment 1. The air return pipe 0122 is divided into a front section 0112 and a rear section 0113. The front section 0112 and the rear section 0113 are connected by a soft cloth bag 033.

[0094] By adopting the above technical solution:

[0095] Another exhaust filtration method is provided, in which the soft cloth bag 033 is directly connected to the air return pipe 0122 and becomes part of the return pipe. When the pulverizer is working, the soft cloth bag 033 inflates, exhausting some air to the outside, while most of the air enters the rear section 0113 of the air return pipe. Fine powder is trapped on the inner surface of the soft cloth bag 033 and is continuously carried away by the return air.

[0096] Example 10:

[0097] This embodiment provides a specific implementation method for an ultrafine pulverizer, such as... Figure 1-4As shown, the other structures are similar to those in Embodiment 1. The outer walls of the crushing chamber 011 and the powder selection chamber 015 are provided with cooling jackets 0119, and the cooling jackets 0119 are provided with cooling water inlet 0120 and cooling water outlet 0121.

[0098] By adopting the above technical solution:

[0099] The cooling jacket 0119 is existing technology and can help reduce the temperature inside the crushing chamber 011.

[0100] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the scope of protection of the present invention.

Claims

1. An ultrafine pulverizer, characterized in that, include: The pulverizer body and the cyclone separator are included. The pulverizer body includes a pulverizing chamber, a toothed ring, an impeller, and a powder selection chamber. A drive shaft is provided on the central axis of the crushing chamber, the impeller is fixed on the drive shaft, and the gear ring is fixed on the side wall of the crushing chamber. The powder selection chamber has a cylindrical structure, with its lower end connected to the crushing chamber and its upper end face closed. A central tube is provided on the central axis of the powder classifier chamber. The upper part of the central tube passes through the upper end face of the powder classifier chamber, and the lower end of the central tube opens into the area near the center of the impeller. The upper part of the central tube is provided with a feed inlet and an air return outlet; The upper end face of the powder selection chamber is provided with a discharge port, which is connected to the air inlet of the cyclone separator through a discharge pipe, and the air return port is connected to the air outlet of the cyclone separator through an air return pipe. It also includes an exhaust filter; The exhaust filter is provided with an exhaust filter inlet, an exhaust filter return inlet, and an exhaust filter outlet, with the exhaust filter return inlet located at the bottom of the exhaust filter; The air inlet and air return outlet of the exhaust filter are located on the same side of the filter material. The air return pipe is divided into a front section and a rear section. The cyclone separator outlet, the front section of the air return pipe, the exhaust filter inlet, the exhaust filter, the exhaust filter return inlet, the rear section of the air return pipe, and the air return outlet are connected in sequence. The filter material of the exhaust filter is a soft cloth bag, with one open end fitted onto the end of the exhaust port of the exhaust filter, and the airflow is discharged from the inside to the outside. Several coarse powder outlets are provided on the upper end face or side wall of the powder selection chamber, and a coarse powder return port is provided on the upper part of the central tube. The coarse powder outlets and the coarse powder return port are connected through a coarse powder return pipe.

2. The ultrafine pulverizer as described in claim 1, characterized in that: The upper end face of the powder selection chamber is a conical structure or a multi-stage conical structure.

3. The ultrafine pulverizer as described in claim 1, characterized in that: The upper end face of the powder selection chamber is a hemispherical or semi-ellipsoidal structure.

4. The ultrafine pulverizer as described in claim 1, characterized in that: The central tube has a circular structure, and the diameter of the feed inlet is smaller than the diameter of the upper end of the central tube. The feed inlet is located at the center of the upper end of the central tube.

5. The ultrafine pulverizer as described in claim 1, characterized in that: A hopper is connected above the feed inlet.

6. The ultrafine pulverizer as described in claim 1, characterized in that: The outer walls of the crushing chamber and the powder selection chamber are provided with cooling jackets, and the cooling jackets are provided with cooling water inlets and cooling water outlets.

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