71 results about "Air classifier" patented technology

The invention discloses a vortex air classifier double-layer rotating cage for sorting superfine powder, and belongs to the technical field of powder preparation. A double-layer rotating cage structure is designed on the basis of centrifugal separation and the sedimentation velocity difference of coarse and fine particles. The specific implementation method is as follows: the outer layer of the rotating cage consists of rotating cage blades which are uniformly distributed in the circumferential direction and is vertically fixed between an upper wheel carrier and a lower wheel carrier, and coarse and fine particles are subjected to centrifugal separation at the rotating cage blades to finish primary grading; the rotating cage inner layer is composed of a drainage cone and a triangular connecting support, the triangular connecting support and the lower wheel carrier are connected and fixed through threads, and the outer edges of the three arc-shaped faces of the drainage cone are attached to the inner edge of the upper wheel carrier. The taper angle of the drainage cone ranges from 5 degrees to 15 degrees, and the axial length of the drainage cone ranges from 1 / 8 to 1 time of the axial length of the rotating cage blade. And coarse and fine particles at the tail end of the drainage cone are separated for the second time due to settling velocity difference. The longer the drainage cone is, the smaller the particle size of the obtained fine powder product is and the narrower the particle size distribution is.

The utility model discloses a center blanking type powder concentrator, which belongs to the technical field of powder grading equipment, and comprises a shell, a powder inlet, a powder outlet and a powder outlet. The rotor is rotationally located in the shell, and a plurality of moving blades are distributed along the circumference of the rotor; one end of the central coal dropping pipe is inserted into the shell and is positioned in a central shaft of the rotor; the powder return cone is connected with the lower part of the shell; the multiple sets of guide vane assemblies are distributed on the periphery of the rotor at intervals along the circumference, one end of each guide vane assembly is connected with the portion, below the powder outlet, of the shell, the other end of each guide vane assembly is connected with the other end of the powder return cone, and partial shielding is formed between every two adjacent sets of guide vane assemblies. The device is used for preventing airflow turbulence of a powder selecting area caused by escape of wind powder flow blown back by passive blades. The problems that in the prior art, air powder flow blown back by a driven blade escapes from a gap between adjacent guide static blades, airflow turbulence is caused, and the sorting efficiency of the powder concentrator is reduced are solved.

The invention relates to the technical field of carbon black production, in particular to a carbon black drying system. In order to solve the technical problem that flue gas generated by a carbon black drying system in the prior art needs to be desulfurized and denitrated, the invention provides a novel carbon black drying system which comprises a cyclone separator, tail gas separated by the cyclone separator and powdery carbon black are cooled by cooling water of a Venturi tube and then enter a main bag filter, and the tail gas and the powdery carbon black enter the main bag filter. Powdery carbon black treated by the main bag filter enters from a pipeline in front of an inlet of a cyclone separator after passing through an air blower and a granulator, and enters the cyclone separator after being subjected to contact heat exchange with a high-temperature gas-solid mixture; high-temperature dry granular carbon black discharged from the lower part of equipment of the cyclone separator is subjected to heat exchange by an air separator, and is screened into residual powdery carbon black and low-temperature dry granular carbon black, the low-temperature dry granular carbon black is conveyed to a carbon black storage system, and the residual powdery carbon black passes through an air blower and then enters a granulator for re-granulation. By means of the drying system, the initial investment cost of carbon black production design is reduced.

This invention relates to the field of impurity removal equipment technology, and in particular to a vibrating air classifier for impurity removal. The device includes a separation chamber with two covers on top. Inside the separation chamber is a fan for removing impurities from the material. Below the fan is a receiving box for collecting the removed material. Inside the separation chamber is a screening mechanism for throwing the material. An adjustment mechanism for moving the fan is located between the fan and the screening mechanism. This invention, through the coordination of the fan, screening mechanism, adjustment mechanism, vibration mechanism, tilting plate, and throwing frame, achieves the reciprocating tilting motion of the throwing frame, continuously throwing the material upwards. This facilitates a secondary, efficient separation of misplaced material and impurities in the air, allowing for precise recycling and reuse of the separated material. This reduces unnecessary material loss, significantly lowers production costs, and effectively reduces the difficulty and cost of subsequent waste treatment and disposal.

The invention relates to a post-treatment system and method for cooling and dedusting carbon black. The after-treatment system for cooling and dedusting the carbon black comprises an air separator, a fan and an elevator, and an air inlet of the fan is connected with an air outlet of the air separator; the elevator is arranged in the vertical direction, a feeding port is formed in the bottom of the elevator, the elevator is connected with a carbon black outlet of the air separator and used for receiving the carbon black output by the air separator, lifting equipment is arranged in the elevator and used for lifting the carbon black, a discharging port is formed in the side, opposite to the feeding port, of the top of the elevator and used for outputting carbon black products, and a third air supplementing port is formed in the top of the elevator. A tail gas outlet is formed in the position, close to the bottom, of the elevator and located on the same side as the feeding port, the tail gas outlet is connected with an air inlet of the fan, and air flow from top to bottom is formed by forming a third air supplementing port in the top of the elevator and forming the tail gas outlet in the bottom of the elevator. According to the post-treatment system for cooling and dedusting the carbon black, efficient cooling and dedusting of the carbon black can be realized, and the productivity is further improved.

A cleaning device for the inner wall of an air classifier includes an air classifier housing, a rotating device, a brushing device, and a lifting device. The inner wall of the air classifier housing has several vertically arranged V-shaped tracks, which are open to communicate with the outside. The rotating device includes a ring-shaped support frame, horizontally arranged, slidably connected to each V-shaped track via an elastic connecting device. The lifting device passes through the open sections of the V-shaped tracks and connects to the ring-shaped support frame to drive the ring-shaped support frame to move up and down along the V-shaped tracks. A stator assembly and a rotor assembly are also included. The stator assembly is concentrically mounted on the ring-shaped support frame, and the rotor assembly is concentrically mounted on the stator assembly. When the stator assembly is energized, it rotates. One end of the brushing device is fixed to the outer periphery of the rotor assembly, and the other end abuts against the inner wall of the air classifier housing. This invention can thoroughly clean fine particles remaining on the inner wall of the air classifier, improving discharge efficiency and reducing material loss.

The airflow classifier comprises a tank body, a collecting frame is arranged on one side of the tank body, a through groove opening is formed in the upper end of the tank body, a collecting pipe is installed in the through groove opening, and the end, away from the tank body, of the collecting pipe extends into the collecting frame. A feeding port communicated with the interior of the tank body is formed in the side wall of the tank body, a baffle matched with the feeding port in size is installed on the inner side wall of the tank body, a screening assembly is arranged on the upper portion of the interior of the tank body, a rolling assembly is arranged below the screening assembly, the rolling assembly is located in the tank body, and the screening assembly is arranged on the upper portion of the interior of the tank body. And hot air blowers are mounted on the two sides of the inner bottom of the tank body. According to the utility model, the uniformity and dryness of bentonite are controlled, and meanwhile, unqualified materials are effectively separated and recycled, so that the production efficiency and the product quality are obviously improved.

This invention discloses a production method for removing foreign matter from sponge titanium, comprising a dustproof shell, a U-shaped frame fixed near the top of the left side wall of the dustproof shell, and rotating rollers rotatably connected between the left and right ends of the two vertical plates of the U-shaped frame, with the two rollers connected by a conveyor belt. Inside the dustproof shell, from left to right, are a feeding channel, a mounting box, and two feeding cylinders. An inclined groove is formed near the corner of the left top wall of the feeding channel, and a connecting cylinder is fixed to the top surface of the feeding channel. An mounting cylinder is fixed to the inner side wall of the dustproof shell, and a blower is installed inside the mounting cylinder. The top of the connecting cylinder is connected to the mounting cylinder. An air classifier is installed in the middle of the bottom wall of the mounting box. An electromagnet is installed on the right inner wall of the dustproof shell. In this invention, magnetic impurities in the sponge titanium are separated by electromagnet attraction, and lighter impurities are separated by the air classifier. Furthermore, the blower can control the speed at which the sponge titanium flies out from the right end of the feeding channel, ensuring thorough air classification of the sponge titanium.

A classifier device, in particular high-performance air classifier, for separating material to be classified into a fine material and a coarse material, the classifier device including: a stationary machine housing, which has a coarse material outlet; a static guide vane basket, which is arranged in the machine housing and which has a guide vane ring formed from a plurality of pivotable flap means; and wherein the guide vane ring further has a nozzle flap means, which is formed to convey a flushing gas volume flow in the direction of the coarse material outlet. The present invention further creates a classifier system with a classifier device of this type as well as a method for operating a classifier device of this type.

The method and installation capable of obtaining a cementitious powder having reduced fiber concentrations. The method comprises providing millimetre-sized granules originating from waste fiber cement material. The granules are supplied to a roller mill (10) comprising a rotating horizontal grinding track (13) and one or more rollers (12) configured to rotate about stationary rotation axes, wherein the granules are ground between the grinding track (13) and a lateral surface of the rotors (12), and reduced to agglomerates comprising micrometre-sized particles. Separation of these particles from the fibers occurs after drying in the milling chamber of the apparatus during an upward air flow. Said smaller-sized particles together with (light-weight) fibers are separated from heavier particles in an air classifier (14). Following this, the smaller-sized particles are separated from the majority of the fibers in a sieve (20).

A device that effectively produce matcha powder is provided and includes: a stirred media mill grinding portion, having a grinding chamber inside, wherein a side of the stirred media mill grinding portion defines an outlet port; a pin bar, rotatably received in the grinding chamber, wherein an outer circumference of the pin bar defines an opening, communicated with the grinding chamber; an air classifier, connected to the outlet port through a first tube assembly and defining a first output port and a second output port; a storage portion, connected to the first output port; a collector portion, connected to the second output port through a second tube assembly; and a wind guider, wherein an air outlet of the wind guider is connected to the outlet port and an interior of the storage portion to create a negative pressure environment.

An air classifier for classifying a mixture of fine and coarse particles by size or aerodynamic shape, wherein the air classifier generally comprises a settling box through which a laminar airflow passes that improves introduction of particles into the airflow and thus improves separation and grading of particles by the air classifier.

The invention relates to a system (1) for preparing coated wood material compression-moulded bodies (100) to form scatterable particles, comprising: a comminuting device (2) for the contact-based comminuting of coated wood material compression-moulded bodies (100) into wood material compression-moulded body fragments with coating-containing wood material compression-moulded body fragments and coating-free wood material compression-moulded body fragments; a riser-pipe air classifier (3) for classification into a bad fraction (31) with predominantly coating-containing wood material compression-moulded body fragments and a good fraction (32) with predominantly coating-free wood material compression-moulded body fragments; an intake device (4) for the weight-dependent and / or time-dependent supplying of the riser-pipe air classifier (3) with wood material compression-moulded body fragments, wherein the intake device (4) comprises a weighing device for the gravimetric determination of the supplying of the riser-pipe air classifier (3) per time unit, wherein the riser-pipe air classifier (3) is downstream of the comminuting device (2) and the intake device (4) is arranged between the riser-pipe air classifier (3) and the comminuting device (2).

This utility model discloses a dust removal and flow assist device for the connecting pipe between an air classifier and a dust collector. It includes an open inclined trough at the bottom of the connecting pipe and an air inlet pipe fixedly connected to the bottom of the open inclined trough. An air storage chamber is provided within the open inclined trough. One end of the air inlet pipe is connected to the air storage chamber, and the other end is connected to a compressed air pipe. A vent cover is fixedly installed at the upper opening of the air storage chamber. Compressed air is introduced into the air storage chamber through the air inlet pipe, and the air in the air storage chamber moves upward through the vent cover. This dust removal and flow assist device for the connecting pipe between the air classifier and the dust collector can achieve dust removal during production, preventing dust accumulation at the bottom of the connecting pipe.

The utility model discloses a multi-cavity feed grinder, and relates to the technical field of feed processing. The device comprises a crushing box, a screening assembly and a winnowing machine, a winnowing machine is arranged at the top end of the smashing box, a screening assembly is arranged in the smashing box, two baffles inclining towards the upper end of the screening assembly are further arranged in the smashing box, a rotating shaft is rotationally connected into the smashing box, a rotating cylinder is fixedly connected to the peripheral side of the rotating shaft, and smashing blades are fixedly connected to the peripheral side of the rotating cylinder. Crushing teeth are arranged on the lower inclined surfaces of the baffles close to the crushing blades; according to the feed grinder, the grinding box, the screening assembly and the winnowing machine are arranged, so that the problem that the whole feed grinder cannot work due to the fact that a single assembly of an existing traditional feed grinder goes wrong is solved, and the problem that the sizes of ground feed particles are different is solved; and the problem that crushed leaves are damaged due to the fact that stones are possibly mixed in the added feed is solved.

The invention discloses an airflow sorting machine for screening lithium battery powder. The airflow sorting machine comprises a screening cavity, a screen, an airflow generating assembly, an anti-blocking assembly and a classification collecting system. The airflow generating assembly generates rotating airflow and a negative pressure environment, and the air distributing head forms a vortex area, so that materials with different particle sizes are efficiently graded; the anti-blocking assembly prevents the screen from being blocked through an ultrasonic generator and an anti-blocking air tap; the grading collection system utilizes a cyclone separator, a bag type dust collector and a large particle collector to accurately collect lithium battery powder with different particle sizes. The screening cavity is divided into an upper cavity and a lower cavity, the screen is detachable, the discharge port is conical, the induced draft fan forms stepped pressure difference, so that separated materials with qualified particle sizes enter the cyclone separator to be collected, efficient and accurate screening is achieved, the maintenance cost is reduced, and the strict requirement of the lithium battery industry for powder screening is met. Different from a traditional screening machine, materials with small particle sizes move upwards through the screen to complete the screening function, and the situation that large materials block the screen can be avoided.

The invention relates to the technical field of automatic manufacturing of rubber products, and discloses a sealing ring multi-stage progressive increase type trimming control system and method based on separation rate feedback, and the system comprises a frequency conversion trimming execution mechanism, a winnowing machine, a visual counting sensor, a shunting mechanism, a backflow channel and a dynamic parameter controller. The method comprises the steps of collecting material images in real time through a visual counting sensor and calculating the proportion of unseparated products; the dynamic parameter controller compares the proportion of the unseparated products with a preset separation threshold value; and when the proportion of the unseparated products exceeds the standard, the shunting mechanism intercepts the materials from entering the backflow channel, and the dynamic parameter controller progressively increases the number of cycles and adjusts the current actual execution strength parameter of the frequency conversion edge removal execution mechanism, so that the physical output strength of the frequency conversion edge removal execution mechanism is progressively increased in a non-linear manner along with the increase of the number of cycles. According to the method, the mechanical damage rate of the sealing ring body is reduced while the stubborn flash removal rate is ensured through the multi-stage progressive increase type parameter adjustment logic.

The utility model provides a horizontal winnowing machine which comprises a horizontal winnowing machine body, a feeding cylinder arranged at the top of the winnowing machine body, a support arranged at the top of the winnowing machine body, a feeding box vertically arranged on the support in a vibrating mode, a screening and filtering cylinder arranged inside the feeding box, and a feeding pipe arranged at the bottom of the feeding box. A feeding hopper is further arranged at the top of the winnowing machine body, a scattering shaft extending to the upper side of the feeding hopper is rotationally arranged in the screening and filtering cylinder, and scattering blades are arranged on the scattering shaft. According to the horizontal winnowing machine, the basic requirement for winnowing treatment of materials can be met, the scattering structure can only scatter caked materials needing to be scattered, and therefore the overall efficiency of feeding and the overall efficiency of winnowing are prevented from being affected.

The present invention relates to the technical field of material separation in waste treatment, and in particular to a spiral air classifier. The spiral air classifier comprises a housing of a cylindrical structure, a discharging pipe arranged at the upper end of the housing, and a feeding pipe located on the upper side wall of the housing below the discharging pipe; a flow-disturbing disc for generating cyclonic airflow is provided in an inner cavity of the housing; a central pipe communicated with the feeding pipe is provided above the flow-disturbing disc; the flow-disturbing disc is transmittingly connected to a driving mechanism; a booster blower is provided on the feeding pipe, and a negative pressure blower is provided on the discharging pipe. The spiral air classifier can achieve separation of impurities by means of cyclonic airflow and centrifugal force, and be used for removing impurities such as sand, soil and gravel having high specific gravity from materials such as plastic films that have low specific gravity and easily float in the air. The spiral air classifier has high separation efficiency, and is particularly applicable to materials having high impurity content.

This invention discloses an ore crushing and pulping system and process, belonging to the field of ore crushing technology. It includes a multi-dimensional rotary toothed pulverizer with a feed inlet at one of its upper openings. An air classifier is mounted on the top of the pulverizer, and an air inlet pipe is connected to its bottom side wall. A fan is mounted at the other end of the air inlet pipe. Several hydrocyclones are connected to the top of the air classifier via pipes. The tops of the hydrocyclones are connected to the fan via return air pipes, and the bottoms of the hydrocyclones are connected to a pulping tank. The pulping tank is connected to a finished pulp pool via a pulp pump. A vacuum exhaust fan and a dust collector are mounted on the return air pipes. This invention's ore crushing and pulping system and process features a short process path, small equipment footprint, high efficiency, low energy consumption, and energy saving and emission reduction.

The invention relates to a method and a device for producing a scattered particle mat (1) from particles (2, 3), for example from lignocellulose-containing material such as fibres or chips or mineral particles, on a running forming belt (23), comprising the following steps: a) providing a bunker (4) having mixed fine and coarse particles (2, 3) which are at least partially provided with a binder, b) dividing the particles (2, 3) emerging from the bunker (4) via at least one size-dividing device (5) into at least one first partial quantity (6) of fine particles (2) and at least one second partial quantity (7) of coarse particles (3), c) further fractionating the at least first partial quantity (6) and the at least second partial quantity (7) again according to particle size, and d) scattering the particles of each partial quantity (6, 7) as a layer having an increasing or decreasing size onto the forming belt (23) in order to form the scattered particle mat (1). In order to reduce the required energy consumption of the scattering device and / or to reduce the overall size, the invention proposes that the first partial quantity (6) of the entire particulate material is fractioned by means of an air classifier (17).

This invention discloses a feeding device and method for a leaf filament air classifier that can improve air separation efficiency. The device includes an incoming material pretreatment unit, an air-separation feeding unit, and a support. The air-separation feeding unit and the support are respectively fixed to the side plates of the conveying component of the leaf filament air classifier. The incoming material pretreatment unit is fixed on the support and is connected to the middle box of the leaf filament air classifier. The incoming material pretreatment unit includes a transmission trough, a high-frequency vibrating motor, a support spring, a screening bar, and a discharge hopper. The air-separation feeding unit includes an air-separation feeding unit box, a high-speed conveyor belt, a first partition, a sealed discharger, a second partition, a pressure plate cavity, and a pressure plate. This invention utilizes the difference in suspension velocity to separate small-sized materials from most of the stems mixed in them. The stems fall and leave the production line through the waste hopper component of the leaf filament air classifier, while the leaf filaments move upward with the airflow and enter the middle box of the leaf filament air classifier through the channel between the first partition and the lower part of the high-speed conveyor belt.

The utility model discloses a multi-point adjustable air inlet mode efficient powder concentrator which comprises a powder concentrator shell, two correspondingly arranged scattering grids are arranged in the powder concentrator shell, end plates are installed on the two scattering grids, a supporting plate is fixedly installed between the two end plates, a telescopic baffle plate is installed on the supporting plate, and the telescopic baffle plate is fixedly installed on the powder concentrator shell. A scattering plate mounted on the scattering grid is arranged at the corresponding position of the telescopic baffle plate, and circular welding spots are uniformly welded on the scattering plate; and an end plate hole is formed in the end plate, a stud is installed in the end plate hole, the stud is movably sleeved with a position adjusting block, and the position adjusting block is welded and fixed to the telescopic baffle plate. By optimizing the scattering plate and adjusting the structural form of the baffle plate, the scattering efficiency is improved, the sorting capacity is improved, and the service life of the scattering grid of the powder concentrator is prolonged.

This invention relates to the field of ball mill technology, and in particular to a ball mill system with an optimized filtration structure and a method for replacing the filter screen. The system includes a frame, with a first top plate and a second top plate mounted on the top of the frame. From left to right, a first bottom plate, a second bottom plate, a third bottom plate, and a fourth bottom plate are sequentially mounted on the middle of the frame. A raw material hopper and a turbine-type air classifier are mounted on the upper end of the first top plate. The lower end of the raw material hopper penetrates the first top plate and is connected to a quantitative feeder, which is mounted on the upper end of the first bottom plate. A ball mill is located at the bottom of the frame. Compared with the prior art, the present invention has a reasonable structural design and effectively allows for timely replacement of the filter device, avoiding waste of filter material due to premature replacement and overloading of the filter material due to delayed replacement, thus improving the filtration effect and effectively enhancing the performance.

This invention belongs to the field of tobacco technology and discloses a heat storage and heating system adapted for tobacco leaf drying in tobacco processing lines. The heat storage unit of the system supplies process hot air to the tobacco leaf drying unit, which is equipped with an air classifier. A tobacco dust processing unit is connected to the air classifier and burns the tobacco dust from the air classifier to supply process hot air to the tobacco leaf drying unit. An energy dispatching unit establishes communication and control links with a photovoltaic access interface, the heat storage unit, the tobacco dust processing unit, and an emergency switching unit. This invention achieves zero carbon emissions for process heating, reduces operating costs, and recycles tobacco dust resources.

This application relates to the field of air classifier mill technology, and provides a feeding device for an air classifier mill, including an air classifier mill body, a mounting frame, and a vibrating mechanism. The upper end of the air classifier mill body is provided with a feed pipe, and the lower end of the air classifier mill body is provided with a feeding pipe. A control valve is installed on the feeding pipe. The vibrating mechanism includes a drive assembly and a vibrating component. The drive assembly includes a motor and a cam. The motor is mounted on the mounting frame and drives the cam to rotate. The vibrating component includes a push plate, a wedge plate, an impact block, and a first elastic element. The push plate is movably inserted through the mounting frame, and the wedge plate is disposed between the push plate and the impact block, located between the mounting frame and the feeding pipe. By setting up the vibrating mechanism, when material is fed through the feeding pipe, the motor drives the cam to rotate. Under the cooperation of the cam and the wedge plate, and the action of the rebound force of the first elastic element, the wedge plate drives the push plate and the impact block to move left and right and continuously impact the feeding pipe, thereby reducing the adhesion and accumulation of material in the feeding pipe and ensuring smooth feeding.

A material recovery system for wet ash generated from municipal waste includes infeed storage of wet ash, an oversized and organic removal subsystem, a material sizing subsystem, a metal recovery subsystem, and an aggregate finishing subsystem. The system for material recovery results in the output of commercially usable aggregate material, ferrous materials, and non-ferrous materials. The subsystems of the material recovery system include one or more screens, dryers, feed hoppers, eddy current separators, magnets, crushers, and air classifiers.

This utility model belongs to the field of air classifier manufacturing technology, and particularly relates to a combined assembly tooling for air classifier rotors. The combined assembly tooling for air classifier rotors includes a base, a limiting seat on the base, a central shaft inside the limiting seat, a pressure plate fitted on the upper part of the central shaft, and a locking nut threaded onto the central shaft above the pressure plate. Multiple uprights are arranged on the base outside the limiting seat, and limiting rings are arranged on the base outside the uprights. During the assembly of the air classifier rotors, the two ends of the central cylinder of the air classifier rotor abut against the limiting seat and the pressure plate, respectively; the upper and lower plates of the air classifier rotor abut against the limiting rings and the upper ends of the uprights, respectively; and the blades of the air classifier rotor abut against the base, with their inner surfaces abutting against the outer surfaces of the limiting rings. This utility model adopts a combined structure, and by replacing different components, it can meet the assembly requirements of various types of air classifier rotors, significantly improving the manufacturing precision and efficiency of air classifier rotors.

The utility model relates to the technical field of powder concentrators, in particular to a powder concentrator lower bearing cooling device which comprises a bearing seat, a lower bearing and a cooling assembly. The end face of the bearing seat is connected with a lower bearing, and a cooling assembly is arranged on the lower bearing. The cooling assembly comprises a cooling water cover, the cooling water cover comprises a first closed shell and a second closed shell, the first closed shell is arranged on the outer side of the lower bearing, and the second closed shell is correspondingly arranged on the other side of the lower bearing; the cooling assembly is arranged on the lower bearing of the powder concentrator, the running temperature of the lower bearing can be reduced through the arranged cooling assembly, heat generated by the lower bearing can be continuously brought out of equipment, long-term stable running of the lower bearing of the powder concentrator is guaranteed, and the service life of the powder concentrator is prolonged.

The utility model discloses an air classifier and a grading separation system, the air classifier comprises a machine shell and a grading wheel, the top of the machine shell is provided with a feeding port, the bottom of the machine shell is provided with a first discharging port, the side face of the machine shell is provided with a second discharging port, the grading wheel is arranged in the machine shell, the grading wheel comprises a rotating cage, and the rotating cage is arranged on the machine shell. The blades of the rotating cage comprise the first blades and the second blades, the width of the first blades is larger than that of the second blades, and the multiple first blades and the multiple second blades are arranged in a staggered mode in the circumferential direction of the rotating cage. The air classifier disclosed by the utility model is simple in structure and has better separation precision and separation efficiency.