56results about How to "Good dustproof effect" patented technology

The invention discloses a panel type loudspeaker used for a mobile phone or a tablet computer. A rear cover of the mobile phone or the tablet computer is provided with a recessed cavity. A thin-film coupling sheet made of soft material and a multilayer piezoelectric ceramic sheet are adhered in the recessed cavity from inside to outside in turn. One side, which is used for accessing electrical signals for the multilayer piezoelectric ceramic sheet, of a flexible circuit board is pressed on the multilayer piezoelectric ceramic sheet, and the other side of the flexible circuit board is pressed on the rear cover. According to the panel type loudspeaker, precious installation space in the mobile phone or the tablet computer is almost not occupied and sound-producing holes do not need to be arranged. Besides, the mobile phone or the tablet computer is great in waterproof and dustproof effect, and sound can be clearly heard in a noisy environment.

The invention belongs to the field of data acquisition devices. The invention particularly relates to a computer data acquisition device and method. The problem that an existing computer data acquisition device is poor in dustproof effect is solved. The data acquisition device comprises a workbench. A first storage groove is formed in the top of the workbench. A mounting plate is mounted in the first storage groove in a sliding manner. A display is fixedly mounted on one side of the mounting plate. A mounting base is fixedly mounted on the outer side of the mounting plate. A camera is mountedat the top of the mounting base. A cover plate is fixedly mounted at the top of the mounting plate. A worm is rotationally mounted on the inner wall of the bottom of the first storage groove. A firstscrew rod is fixedly mounted at the top of the worm and is in threaded connection with the mounting plate. A second storage groove is formed in the bottom of one side of the workbench, and a bottom plate is slidably mounted in the second storage groove. The dustproof effect is very good, and the occupied space during placement can be reduced through storage of a seat plate.

The invention discloses a double-pattern pipe dust-proof heat exchanger, which consists of outer cylinder and inner cylinder, wherein the inter cylinder is encased in the outer cylinder; the scattering shape recuperative fin is set on outer side wall of inner and outer cylinders, which is wrapped by recuperative pipe to display spiral shape. The invention improves the recuperative efficiency, which possesses the excellent dust-proof effect due to dust accumulation quantity reduction.

The invention discloses a filter cloth positioning and cutting device. The filter cloth positioning and cutting device comprises a top plate, wherein guide columns are symmetrically and fixedly arranged on the top plate, and symmetrical hydraulic cylinders are fixedly connected to a positioning plate; an annular groove is formed in the top plate, a rotating shaft is fixedly arranged on the side, far away from the top plate, of a rotating rod, a lifting air cylinder is fixedly arranged in an installing groove, and a cutting knife is arranged on the lifting air cylinder; and a threaded hole is formed in the side, opposite to a limiting plate, of the center of the top plate, a threaded rod is movably arranged in the threaded hole, and a central pressing plate is fixedly arranged at the end, far away from the threaded hole, of the threaded rod. According to the filter cloth positioning and cutting device, the structure for double fixing and pressing an outer layer and the center of a filter cloth raw material is arranged in the device, so that the side edge of to-be-cut filter cloth is always in the straining state, the condition that the filter cloth subject to partial side edge cutting is inclined, so that cutting of the residual side edge is influenced is avoided, meanwhile, a dust collection device and a dust suction device are arranged in a built-in mode, and the dust prevention effect is good.

The invention relates to a building interphone with lifting and dustproof functions for security and protection. The device comprises a main machine, a base and two lifting boxes, the interphone further comprises a dustproof mechanism and two lifting mechanisms. Each lifting mechanism comprises a first motor, a gear, a rack and a connecting rod; the dustproof mechanism comprises a fixing box and two cover plates; a driving assembly, two supporting rods and two springs are arranged in the fixing box. In the building interphone with the lifting and dustproof functions for security and protection, through adopting the lifting mechanisms, the height position of the main machine can be adjusted, users of different heights can operate the main machine conveniently, a display screen and a controlpanel on the main machine can be subjected to dustproof work through the dustproof mechanism, and the situation that the cleanliness of the main machine is affected due to the fact that the display screen and the control panel are covered with dust is avoided.

The invention relates to the technical field of power equipment. The invention further discloses a heat dissipation and dust prevention device of an independent equipment power cabinet based on the electromagnetic induction principle. The device comprises a first shell and a second shell, a positive electrode is fixedly connected to the interior of the first shell, a negative electrode is fixedlyconnected to the interior of the first shell, a supporting rod is movably connected to the interior of the first shell, a copper rod is fixedly connected to the top of the supporting rod, and a push rod is fixedly connected to the exterior of the copper rod. Under the interaction of a driver, a connecting rod I, a connecting rod II, a connector, a sliding rail, a baffle, a gauze element and a storage box, the rotating speed of a grooved wheel can be adjusted through the clamping relation between a rotating wheel and the grooved wheel, the lifting height of the baffle can be adjusted by changing the rotating speed of a driving motor, and the baffle can drive the gauze to shield an opened air outlet, so that a certain dustproof effect can be achieved when the power cabinet operates, the sizeof the air outlet is manually adjusted according to the use condition of the power cabinet, and heat dissipation under different conditions is more convenient.

The invention discloses an efficient dust-free stone breaker. The efficient dust-free stone breaker comprises a shell and a dust cover, the dust cover is installed on the lower side of the shell, handles are fixedly installed on the upper portions of the left end and the right end of the shell respectively, anti-slip sleeves fixedly sleeve the handles, an electric servo cylinder is fixedly installed in an inner cavity of the shell through fastening bolts, a push rod is fixedly installed at the lower end of the electric servo cylinder, a drill bit is fixed to the lower end of the push rod, a casing pipe is fixedly connected to the lower end of the shell, a spring is movably installed on the annular side face of the casing pipe, the upper end of the spring makes contact with the lower end ofthe shell, a connecting ring is movably installed on the spring and at the lower end of the casing pipe, the dust cover is fixedly installed at the lower end of the connecting ring, an arc-shaped baffle is rotationally installed on the right portion of the dust cover through a hinge, and an elastic string is fixedly installed at the right side of the inclined plane of the arc-shaped baffle. The efficient dust-free stone breaker is simple in structure, convenient, practical, good in dustproof effect and ingenious in design.

The invention relates to a bearing structure. It is characterized in that the dust-proof cover is insulated from the outer ring, and an electrostatic dust-absorbing device is provided on the dust-proof cover, and the electrostatic dust-absorbing device includes an electrostatic brush and an electrostatic dust-absorbing net. There are bristles in contact with the electrostatic dust collection net, and the electrostatic brush is connected with the inner ring. In the present invention, by adopting the above technical scheme, the dust cover has no contact with the inner ring or outer ring of the bearing, and has no influence on the normal operation of the bearing. The bearing and the dust cover are insulated and matched, so static electricity can be generated by friction on the dust cover. When the electrostatic device works through the bearing, the inner ring rotates. The brushes fixed on the inner ring and the electrostatic dust collection net on the dust cover rub each other to generate static electricity. The friction between the bristles and the electrostatic dust collection net is very small and can be ignored. Regardless, the generated static electricity absorbs nearby dust, reducing the probability of dust passing through the gap between the dust cover and the bearing, and the dustproof effect is good.

The invention relates to a device for concrete precast elements, in particular to a vibration-isolating support type concrete manufacturer with blades provided with holes. The vibration-isolating support type concrete manufacturer with the blades provided with the holes comprises a container and the stirring blades. The container is provided with a material feeding hole, damping support mats, a water supplementing chamber and a middle water chamber. The material feeding hole is provided with an annular water discharge channel. The annular water discharge channel is provided with water spray holes. The water supplementing chamber communicates with the middle water chamber through a first one-way valve. The middle water chamber communicates with the annular water discharge channel through asecond one-way valve. An energy recycling structure is arranged in the container and comprises a cylinder block, a piston, a piston rod, an upward movement piston spring and a press bearing plate. Thecylinder block communicates with the middle water chamber through a water flow channel. Each stirring blade comprises at least two branch blades. One end of each branch blade is connected with a stirring shaft, and the other ends of the branch blades of each stirring blade are connected through an end plate. A channel is formed between every two adjacent branch blades. The vibration-isolating support type concrete manufacturer with the blades provided with the holes has the advantages being good in extruding and stirring effect and good in vibration isolating effect and generating little flying dust during production, and the problem that manual concrete mixing and manufacturing is arduous is solved.

The invention relates to a dustproof device, in particular to a radio dustproof device for electronic communication, and aims at solving the technical problem of providing the radio dustproof device for electronic communication with a good dustproof effect, relatively multiple functions and simplicity in operation. The invention provides the radio dustproof device for electronic communication to solve the technical problem. The radio dustproof device comprises a cover plate, a rotating shaft, a motor I, a bracket I, a placing rack, an electromagnet, a vibration absorbing device, a motor II, a rack, a sliding block, a gear, a bracket II, a sliding rail and a placing box; the bracket I is arranged at the upper part of the right side of the placing box and is connected with the motor I; the motor I is provided with the rotating shaft; the rotating shaft is connected with the cover plate; the bracket II and the sliding rail are arranged at the bottom in the placing box; the bracket II is located at the right side of the sliding rail; the upper end of the bracket II is connected with the motor II; the gear is arranged at the rear side of the motor II; and the sliding rail is provided with a sliding block. According to the radio dustproof device for electronic communication, the beneficial effects that the radio dustproof device is good in dustproof effect, relatively multiple in function and simple in operation are achieved.

The invention relates to an air-cooled host case with the internal environment temperature adjusting function and a method. The host case comprises a host case body. The host case body comprises a left side plate and a right side plate; a main control panel is fixedly arranged on the left side plate; a CPU is fixedly arranged on the main control board; a turntable, a rotating assembly, a lower fanplate, a first heat dissipation assembly and a second heat dissipation assembly are arranged in the host case; the first heat dissipation assembly comprises a first iron block, a heat conduction needle set and a first reset spring. The second heat dissipation assembly comprises a second iron block, a mounting plate, a first heat dissipation fin group and a second reset spring; an upper fan plateis also arranged in the host case; the upper fan plate is fixed with the transverse plate body of the mounting plate; an electromagnet is fixedly arranged on the surface of the right side of the lowerfan plate; a first movable through groove is formed in the right side plate; the first movable through groove allows the heat conduction needle set or the first cooling fin set to penetrate out of the host case. The computer case is flexible and diverse in heat dissipation mode, more efficient in heat absorption and heat dissipation and good in dustproof effect.

The invention relates to power distribution equipment, in particular to a transformer, a power distribution box and a power distribution area. The power distribution area comprises a transformer and apower distribution box, a low-voltage outgoing line plugging structure connected with a low-voltage side is arranged on the side wall of a shell of the transformer, and a low-voltage incoming line plugging structure is arranged on the side wall of a box body of the power distribution box; or, the bottom wall of the shell of the transformer is provided with a low-voltage outgoing line plugging structure connected with the low-voltage side, and the top wall of the box body of the power distribution box is provided with a low-voltage incoming line plugging structure; the transformer and the power distribution box realize wiring through sealed plugging of the low-voltage outgoing line plugging structure and the low-voltage incoming line plugging structure. The transformer and the power distribution box are electrically connected through plugging connection, a conductor is not exposed, cable connection is not needed, and wiring is more standard. The problems that a transformer low-voltagebinding post and a power distribution box incoming line terminal of an existing power distribution area are exposed, and wiring between the transformer low-voltage binding post and the power distribution box incoming line terminal is messy are effectively solved.

The invention relates to the technical field of numerical control machine tools, in particular to a multifunctional telescopic servo waterwheel electric spindle. The multifunctional telescopic servo waterwheel electric spindle is waterproof, dustproof and sealed in a non-contact mode, and can rapidly and comprehensively cool heat of a cutter and a workpiece in the cutting machining process, so that the surface machining quality of the workpiece is improved, and the service life of the cutter is prolonged. The multifunctional telescopic servo waterwheel electric spindle comprises a sleeve, a spindle body, a stator and rotor assembly, an electric spindle encoder and a cooling system. A front bearing set and a rear bearing set are installed on the front portion and the rear portion of the spindle body respectively. The front bearing set, the rear bearing set, the sleeve and bearing end covers located at the two ends of the sleeve jointly form an integral sealing cavity. A waterproof coveris fixed to the spindle body and can rotate along with the spindle body. The waterproof cover and a front gland groove form a labyrinth type waterproof structure. An air sealing annular groove and alabyrinth type sealing groove are formed between the waterproof cover and a front gland. The cooling system comprises cooling liquid channels uniformly arranged on the sleeve and eight cooling nozzlesarranged on a box body.

The invention relates to a speed reducer, in particular to a special speed reducer for a fully automatic solar single crystal furnace. It mainly solves the technical problems existing in the prior art that the reducer has poor sealing performance and cannot play a role in heat dissipation during operation, so it cannot be applied to solar single crystal furnaces. The present invention includes a main box body, the main box body is provided with an input shaft, the input shaft is connected with a first-stage worm gear, the first-stage worm wheel is connected with a second-stage worm wheel through a worm, and the second-stage worm wheel is connected with an output shaft, the first-stage worm wheel, the second-stage worm wheel The outer ends of the worm wheels are provided with seals.

The invention relates to auxiliary equipment for teaching, in particular to a dust-free blackboard eraser. The dust-free blackboard eraser comprises a blackboard eraser body (1). The blackboard eraser body (1) comprises two or more cotton-wool brush rolls (2). The cotton-wool brush rolls (2) of the blackboard eraser are connected with a dust storage box body (3) through rotating shafts. The distance between every two adjacent cotton-wool brush rolls (2) ranges from 0.8 cm to 1.5 cm. A brush body (4) is arranged at the position, below each cotton-wool brush roll (2), inside the dust storage box body (3). The free end of each brush body (4) is in close contact with the corresponding cotton-wool brush roll (2). A connecting plate (5) for connecting the brush bodies (4) is of a net structure. Dust humidifying devices (6) are arranged at the positions, below the connecting plate (5), inside the dust storage box body (3). A control switch is arranged at the outer side of the dust storage box body (3). The dust-free blackboard eraser has the beneficial effects that the structure is simple; production cost is low; chalk dust cannot fly everywhere in the blackboard erasing process; in addition, the chalk dust cannot fall onto the ground; and the dust prevention effect is good.

The invention relates to a dustproof cabinet of a computer for agricultural machinery, which comprises a main case. The main case is movably connected with a case door. Universal wheels are arranged at the bottom of the main case. The left end and the right end of the main case are fixedly connected with a first ventilation box and a second ventilation box correspondingly. Air inlets are formed inthe first ventilation box and the second ventilation box; dust removal openings are formed in the bottoms of the first ventilation box and the second ventilation box; a sealing cover is in threaded connection with the dust removal opening; a cooling fan is arranged on the inner wall of the top of the main case; a fixed base is arranged on the inner wall of the bottom of the main case, and the topof the fixed base is fixedly connected with a movable base through first springs. Fixed baffles are symmetrically connected to the top of the movable base, and a movable baffle is fixedly connected to one side of each fixed baffle through a second spring, so that good dustproof, ventilation, heat dissipation and shock absorption functions are achieved, the severe use conditions of the computer for the agricultural machinery can be met, and the service life of the computer is effectively prolonged.

The invention discloses an antistatic dustproof cell phone horn comprising an antistatic loop, a support, an outer cover, a sound collecting cylinder, magnets, yokes, a pedestal equipped with grooves, and a vertical column. The vertical column is disposed on the center of the pedestal equipped with the grooves. The pedestal equipped with the grooves and the vertical column are integrally formed. The yokes are disposed on the two side grooves of the pedestal equipped with the grooves. The magnets are disposed over the yokes. An inner pressure sheet is arranged over the magnets. A vibrating diaphragm is arranged over the inner pressure sheet. The antistatic loop sleeves the outer side of the vibrating diaphragm. The vibrating diaphragm is arranged in the sound collecting cylinder. The sound collecting cylinder in a basin stand shape is disposed over the outer sides of the yokes. The top of the sound collecting cylinder is provided with an outwardly-bent edge. A dustproof diaphragm is disposed over the sound collecting cylinder. An outer pressure sheet is disposed over the dustproof diaphragm. The dustproof diaphragm and the outer pressure sheet successively press the bent edge of the sound collecting cylinder. The bent edge is pressed on the top end face of the support. The outer side of the support is provided with an outer cover buckled on the periphery of the support.

The invention discloses a method for detecting the advancing safety of a climbing-free device of a wind power tower drum. The method comprises the following steps of: S1, detecting field environment facilities; S2, detecting the appearance of equipment; S3, detecting main components; S4, detecting a safety protection and protective device; S5, detecting a control system; S6, detecting an electrical system; S7, detecting noise; S8, detecting an operation test; and S9, performing regularly and additionally detection for the first time of new installation. According to the method, each component part and the working environment of the climbing-free device are detected, so that the condition that the equipment has faults during working is effectively eliminated; the climbing-free device can be in a stable operation state during working, so that the use safety of a user is effectively improved; and meanwhile, an environment monitoring device is arranged in the working environment and the lighting function is added, so that a stable guarantee is provided for normal operation of the climbing-free device.

The invention discloses a valve-equipped cylinder special for a polisher, comprising a cylinder body, wherein a piston rod is arranged in the cylinder body, one end of the piston rod passes through the cylinder body, the other end of the piston rod is sleeved with a piston, a piston-near end is provided with a rear cover, and the upper end of the cylinder body is provided with an air inlet valve for controlling an air circuit; and the piston rod is provided with a reset spring. The cylinder has the advantages of durability, energy-saving, no impact sound and small volume, can prevent the piston rod from rotating.

The invention discloses a household smoke detection camera device with favorable induction performance. The household smoke detection camera device comprises a shooting cylinder, a shell, a support rod and a cooling net, wherein an infrared lamp tube is fixedly arranged on an inner surface of the shooting cylinder, dustproof glass is fixedly arranged on an outer surface of the infrared lamp tube,a camera is movably arranged in the infrared lamp tube, a smoke detector and an alarm are arranged on an inner surface of the shell, the alarm is fixedly arranged at one side of the smoke detector, anemergency power supply is fixedly arranged on an outer surface of the shell, and an emergency lighting lamp and a warning lamp are arranged at a bottom end of the shell. In the household smoke detection camera device with favorable induction performance, an anti-slip cushion layer, the emergency lamp and the emergency power supply are arranged, a fixed base can be more stable to connect, emergency lighting can be achieved, equipment also can be endured when power is in failure, and the household smoke detection camera device with favorable induction performance is applicable to different working conditions and brings a better application prospect.

The invention discloses a cooling apparatus with a dustproof function for a computer. The cooling apparatus comprises a host, a sliding slot, a fan outer cover, support legs and a placement plate; strip-shaped cooling holes are formed in the front surface of the host; the sliding slot is reserved in the left side of the host; a base is mounted at the bottom of the host; the fan outer cover is mounted outside a cooling fan; the support legs are symmetrically arranged at the left and right ends of the lower part of the base; the placement plate is connected with a side slot; a cooling plate is mounted on the right side of the host; a dustproof net is mounted on the left side of the host; a placement slot is formed in the upper surface of the base; cotton cloth is mounted on the placement plate; and strip-shaped baffle blocks are arranged on the strip-shaped cooling holes. According to the cooling apparatus with the dustproof function for the computer, heat in the host can be convenientlyemitted through the strip-shaped cooling holes formed in the front surface of the host; and the strip-shaped baffle blocks are mounted on the strip-shaped cooling holes, so that a good dustproof effect is achieved.

The present invention discloses a refrigerating dustproof chassis. The chassis comprises a chassis body and a side cover. The chassis body and the side cover are combined so as to form a closed chassis. The chassis further includes a heat dissipation bin and a power bin. The power bin and the heat dissipation bin are disposed outside the chassis body and are fixedly connected with the chassis body. The inner wall of the heat dissipation bin is provided with heat dissipation fins. The heat dissipation bin is internally provided with a heat dissipation tube and a cross flow fan that are contacted with the heat dissipation fins. The chassis body is internally provided with a heat flow bridge. The heat flow bridge is connected with the heat dissipation fins in the heat dissipation bin. The refrigerating dustproof chassis has the advantages that heat generated by a heat generation element in the chassis body is transported to the heat dissipation bin through the heat flow bridge, and heat in the heat dissipation bin is dissipated by the heat dissipation fins and the cross flow fan, so that less heat is accumulated in the chassis body, and the heat generation element in the chassis body is protected; a semiconductor refrigerator reduces residual heat in the chassis and dehumidifies, so that a normal temperature and humidity environment in the chassis body is ensured effectively; and the interior of the chassis body is not contacted with external air directly, so that the dust is prevented from entering the chassis body effectively, and a good dustproof effect is achieved.

The invention provides a computer host with a good dustproof effect, and relates to the technical field of electronic equipment. The computer host with the good dustproof effect comprises a computer host shell, a driving device is installed on the front face of the computer host shell, supporting blocks are fixedly connected to the periphery of the lower surface of the computer host shell, a mainboard is fixedly connected to the inner left wall of the computer host shell, and a power box is fixedly connected to the inner left wall of the computer host shell. The invention discloses a computerhost with a good dustproof effect. Small holes are formed in a blocking plate, and a blocking frame is placed below the blocking plate. the cellular board is fixedly connected with the computer hostshell through screws in a matched manner; The dustproof effect of the computer host is good, and the problems that under the condition that a fan works for a long time, some dust can be sucked into the computer host, much dust is likely to adhere to the fan, the heat dissipation effect is reduced, the computer host is likely to be damaged, and economic losses are indirectly caused are effectivelysolved.

The invention belongs to the technical field of power distribution cabinets, and particularly relates to a dustproof power distribution cabinet which comprises a power distribution cabinet body, two cabinet doors are hinged to one side of the power distribution cabinet body, the sides, close to each other, of the two cabinet doors are each provided with a first rectangular hole with an opening in one side, the inner walls of the two sides of the power distribution cabinet body are each provided with two second rectangular holes, the same first filter plate is fixedly mounted on the inner walls of the two sides of the power distribution cabinet body, a heat dissipation mechanism is fixedly mounted at the bottom of the first filter plate, and a dustproof mechanism is fixedly mounted at the two sides of the power distribution cabinet body; wherein the dustproof mechanism comprises a rectangular box, and the rectangular box and the power distribution cabinet body are fixedly connected together. According to the power distribution cabinet, the power distribution cabinet body 1 can be effectively cooled, dust can be prevented from entering the power distribution cabinet body in the heat dissipation process of the power distribution cabinet body, a high dustproof effect is achieved, and a good working environment is provided for components in the power distribution cabinet body.

The invention discloses a dustproof numerical control device comprising a work room and a first dedusting chamber, wherein a side face of the work room is provided with a first movable door and an operation panel, the first dedusting chamber is positioned on a bottom part of the work room, a side face of the first dedusting chamber is provided with a second movable door, each of the first movable door and the second movable door is provided with a handle, two sides of the second movable door are provided with ventilation windows, internal parts of the two ventilation windows are provided with dustproof nets, a second dedusting chamber and a support leg are respectively fixed on a bottom part of the first dedusting chamber, a top part of the second dedusting chamber is communicated with the bottom part of the first dedusting chamber, and a bottom part of the second dedusting chamber is provided with first via holes that are arranged at a uniform interval. The dustproof numerical control device is high in dustproof effect and can effectively prevent jamming problems, and normal usage of the device can be ensured; the dustproof numerical control device is simple in operation, high in practicality and convenience, high in stability and long in service life.

The invention provides a novel steering column dust shield to solve the problems that the conventional automobile steering shaft shield has poor shielding effect and short service life, and relates to the field of automobile steering shaft shields. The novel steering column dust shield comprises a steering transmission shaft shield, a steering transmission shaft shield pressure plate and two steering shaft sealing rings arranged inside the steering transmission shaft shield, wherein corresponding mounting through holes are formed in the steering transmission shaft shield and the steering transmission shaft shield pressure plate; positioning columns are arranged on the steering transmission shaft shield; positioning holes are formed in the steering transmission shaft shield pressure plate. According to the invention, the novel steering column dust shield mainly prevents pollutants and muddy water from entering an automobile steering gear to cause the malfunction of a steering system, and adopts a separated structure; the assembly parts are rubber parts, have excellent elasticity and long service life; the muddy water and dust isolating effect is excellent and the steering transmission shaft is effectively kept away from pollution of outside pollutants in virtue of the two framework seal rings arranged inside the steering transmission shaft shield.

The invention discloses an indirect air cooling type condenser inlet air dust-proof filtration device, and relates to a dust-proof device. The device comprises a detachable dust-proof screen, an air inlet passage, inlet air and outlet air isolation air deflector and an air outlet, wherein the air inlet passage of a machine room is provided with the detachable dust-proof screen; the air outlet passage of the machine room is provided with a condenser; the inlet air and outlet air isolation air deflector is arranged on an air leakage part around the condenser and guarantees that all inlet air blows over the condenser and then flows out from the air outlet. The dust-proof screen has the advantages of convenience in disassembly, easiness in cleaning and good dust-proof filtration effect.