75results about How to "Easy to disassemble, replace and maintain" patented technology

The invention discloses a full-automatic coagulate blood analytical instrument and a using method thereof. The instrument comprises a sample position module, a reagent position module, an incubation detection module, a gripper module, a cupping module, a needle movement module, a light source module, a pump station module, a consumable module, a power source module and a cuboid-shaped frame body composed of six faces of a front face, back face, left side face, right side face, top face and bottom face, wherein the center in the frame body is provided with a main cavity, the sample position module, the reagent position module, the incubation detection module, the gripper module and the needle movement module are all located in the main cavity, the left side face of the frame body is provided with a left side cavity, the pump station module is located in the left side cavity, the right side face of the frame body is provided with a right side cavity, the consumable module and the light source module are located in the right cavity, the cupping module is located in the right side cavity and penetrates into the main cavity, the back face of the frame body is provided with a back cavity, the power source module is located in the back cavity, and through the synergy of the modules, the full-automatic coagulation analysis is achieved.

The invention discloses a combined type brush sealing structure with a radially adjustable brush wire bundle. The sealing structure comprises the following components: a front baffle, a back baffle, brush wire rings, fastening screws, bearing plates, w-shaped sealing rings and a stator casing, wherein roots of brush wires are fixed on an annular plate through a fusion welding process, so that an upstream brush wire ring, a midstream brush wire ring and a downstream brush wire ring are formed; the brush wire rings are divided into a plurality of sector sections circumferentially; the w-shaped sealing rings are clamped through brush sealing components and the stator casing; the bearing plates are installed in the stator casing and located between two brush wire rings; the lower ends of the fastening screws are inserted into the stator casing and located at the fixed ends of the brush wire rings; the fixed ends of brush wires are located on the brush wire rings, and the free ends of the brush wires make contact with a rotor; and the fastening screws acts on the brush wire rings through the stator casing. According to the combined type brush sealing structure, on the premise that a brush seal is not disassembled, the radial clearance between the brush wires and the rotor can be adjusted; besides, disassembly, replacement and maintenance are facilitated; the sealing property of the brush seal can be improved remarkably, and the usage cost is reduced; and excellent economic benefit is achieved.

The invention discloses an intelligent building security monitoring device based on a wireless network. The device comprises a mounting base and a management cabinet, the bottom of the management cabinet is integrally connected with a power distribution box; the power distribution box is clamped and fixed at the top of the mounting base; four sets of spring shock absorbers are symmetrically installed at the bottom end of the interior of the management cabinet. The top ends of the spring shock absorbers are fixedly connected with a tray; a first forward and reverse rotation motor is fixedly mounted at the top of the tray; and a top rotating disc of the management cabinet is arranged, stand columns are symmetrically welded to the two sides of the top of the rotating disc, a shooting device is rotationally connected between the two stand columns through a pin shaft, an acousto-optic buzzer is installed at the top of the shooting device, and a signal collection box and a wireless communicator are embedded into the two sides of the management cabinet correspondingly. The system is simple and reasonable in structural design, convenient to operate, disassemble, assemble and replace, capable of effectively achieving tracking shooting and conveniently summarizing and uniformly managing data, capable of supporting remote control, safe, stable, wide in application range and beneficial topopularization and popularization.

An efficient nano-infrared energy-saving low-temperature hot stick is formed by sequentially connecting an evaporation section and a condensation section. The efficient nano-infrared energy-saving low-temperature hot stick is characterized in that a heating outer tube (5) is additionally arranged on the evaporation section, and a nano-alloy material molecular vibration dark infrared heating wire (9) is spirally arranged in the heating outer tube (5) in the longitudinal direction; multiple heat-sensitive sensors (8) are mounted in the heating outer tube (5); a center temperature measuring tube (7) is arranged at the center of the condensation section, the heat-sensitive sensors (8) and the center temperature measuring tube (7) are connected with a temperature control device (2), and the temperature control device automatically controls the heating outer tube (5) to heat the evaporation section; and the nano-alloy material molecular vibration dark infrared heating wire (9) is electrically connected with a storage battery (3), and the storage battery (3) is charged by a solar power generation panel (4). The efficient nano-infrared energy-saving low-temperature hot stick is simple in structure, safe and reliable to work, efficient and capable of saving energy, solving the problem of frost heave of roadbeds in frozen earth regions and improving the safety and stability of the roadbeds.

The invention discloses a high-performance multi-storage modular server which comprises a bottom shell and a cover plate; a mainboard and a first hard disk module are arranged in the bottom shell; the first hard disk module comprises a first hard disk mounting frame and a plurality of first hard disks, the first hard disk mounting frame is provided with a plurality of pluggable cavities, and thefirst hard disks are arranged in the pluggable cavities in a drawer type hot pluggable mode; a fan module is detachably arranged on one side of the first hard disk module, the fan module comprises afan mounting frame and a plurality of first cooling fans, the fan mounting frame is provided with a plurality of mounting cavities, and the first cooling fans are detachably arranged in the mounting cavities; a heat dissipation air duct is arranged on the other side, deviating from the first hard disk module, of the fan module; a button module is arranged on the outer side wall of the bottom shelland protrudes out of the bottom shell. Therefore, modular design of the hard disks, the fan module and buttons is achieved, detachable design of the hard disks and the fans is achieved, disassembly and assembly and later maintenance and replacement are facilitated, and better heat dissipation performance is achieved.

The invention discloses a solar automatic cleaning device for an indication board on an expressway. The device includes a frame main body, the frame main body is provided with a main shaft, the frame main body is provided with fixed cards, the fixed cards are arranged on four sides of the frame main body, each side of the frame main body is provided with two fixed cards, one side of the frame main body is provided with an auxiliary shaft, and the frame main body is provided with a rolling cylinder brush. According to the solar automatic cleaning device for the indication board on the expressway, by the fixed cards on the frame main body, the whole solar automatic cleaning device is fixed on the indication board, a timing rotation motor uses the power supplied by a solar panel, the timing rotation motor drives the rolling cylinder brush to clean the surface of the indication board, after the rolling cylinder brush wipes from one end to the other end, the timing rotation motor rotates reversely to drive the rolling cylinder brush to return to the initial position, and the scrubbing process is completed once; the timing rotation motor can be set to conduct the cleaning at fixed intervals, and when conducting the cleaning once, the timing rotation motor drives the rolling cylinder brush to move between two sides of the indication board many times. Meanwhile, the solar automatic cleaning device is simple in structure and easy to maintain.

The invention belongs to the technical field of laser welding, and particularly relates to a panel pressing device applied to laser tailor-welding. The panel pressing device comprises a pressing beam and pressing components, wherein the pressing beam is provided with a plurality of stepped through holes along the length direction; one set of the pressing component is arranged in each stepped through hole. According to a method, a plurality of groups of pressing components are used for vertically acting on a welded panel, and a plurality of groups of pressing load are applied, so that the welded panel can be pressed and fixed. The device disclosed by the invention has the advantages of being simple in structure, low in cost, convenient to dismount, replace and maintain and the like; the method is good in pressing effect, uniform in pressing force and high in panel correction quality; the panel can be effectively fixed; the requirements of laser tailor-welding on flatness of the pressed panel are satisfied; the welding quality are ensured not to be affected by cracking of the edge of the panel due to welding stress caused in a welding process.

The invention discloses a magnet-containing brush-type sealing structure capable of adjusting the radial clearance between brush wire beams and a rotor surface. The brush-type sealing structure comprises a stator, a brush-type sealing component and tile-shaped magnets, wherein the brush-type sealing component is arranged on the inner circumference of the stator in a matching manner, is capable ofmoving on the inner side of the stator in the radial direction of a rotor, and comprises an upper brush-type sealing component and a lower brush-type sealing component; both the upper brush-type sealing component and the lower brush-type sealing component comprise front baffle plates, fusion welding zones, rear baffle plates and the brush wire beams; bolts are correspondingly fixed at the middlesof the outer circumferences of the upper brush-type sealing component and the lower brush-type sealing component; after penetrating through the through holes, matched with the bolts, of the stator, the bolts are screwed by nuts; the tile-shaped magnets are arranged in pairs and mutually repelled; and each pair of the tile-shaped magnets comprises the tile-shaped magnet fixed on the outer circumference of the brush-type sealing component and that fixed on the inner circumference of the stator. The brush-type sealing structure has the beneficial effects that the radial clearance between the brush wire beams and the rotor surface can be adjusted by loosening or tightening the nuts; and through the uniformly-distributed tile-shaped magnets, the smooth rotation of the rotor can be guaranteed.

The invention discloses an integral plugged electric-hydraulic control reversing valve with a stage filtering function, comprising a support filter, a pilot valve filter and a reversing valve set. The integral plugged electric-hydraulic control reversing valve with the stage filtering function is characterized in that the support filter and the pilot valve filter are integrally arranged in the reversing valve set; the reversing valve set is provided with a liquid inlet, a first liquid inlet and a second liquid outlet, and the liquid inlet is communicated with the support filter; and the support filter and the pilot valve filter are arranged between passageways. The electric-hydraulic control reversing valve integrates the support filter and the pilot valve filter into a whole main valve body to form a plugged structure; a high-pressure liquid is filtered by the support filter, one path of the liquid directly enters a valve core high-pressure port of the integral main valve, and the other path of the liquid enters the pilot valve filter and provides liquid for the pilot valve after secondary filtering. The pilot valve and the main valve have different requirements on filtering precision of a working medium, the pilot valve requires high cleanliness of the working medium and small amount of liquid quantity while the main valve requires relatively lower cleanliness of the working medium and large amount of liquid quantity, therefore, the stage filtering function can effectively control the cleanliness of the work medium and ensure the normal use of the main valve and the electro-magnetic pilot valve.

The invention discloses a two-stage valve. A primary valve plug assembly and a secondary valve plug assembly coaxially installed in the primary valve plug assembly are independently used for adjustment, the structure is simple, compared with a traditional valve of a single-stage valve plug assembly structure, the two-stage valve is better in accuracy, the adjusting density of the primary adjusting valve plug assembly is A, the adjusting density of the secondary adjusting valve plug assembly is B, the adjusting density of the valve is A * B, adjustment is more precise, and the adjusting density of the traditional valve is only A or B.

The invention belongs to the technical field of electric vehicle charging piles, in particular to a novel safety protection new energy electric vehicle charging pile, which comprises a terminal insulating roof cover. A module layer frame, a heat dissipating device and a hidden signal antenna are installed inside a charging pile body. A travel switch is disposed on the bottom of the charging pile body. Module layer frame sliding grooves are disposed on the left and right sides of the bottom of the charging pile body. The module layer frame has an internal component frame, a DC mounting plate member and an AC module mounting plate. The novel safety protection new energy electric vehicle charging pile prevents signal shielding, ensures the stability of signal transmission, has low transmission power loss and a good heat dissipation effect, is easy to install and easy to disassemble and replace, greatly improves operability and safety, and has good waterproof and dustproof performance. Theconcealed lifting position can achieve convenient transportation and placement. The novel safety protection new energy electric vehicle charging pile can be and hidden after moved, and the overall appearance of the electric vehicle charging pile is not influenced.

The invention relates to a conveniently detached assembling flat plate type metal guard bar which comprises a plurality of metallic vertical columns, wherein the metallic vertical columns are spaced and vertical; one or more metallic cross beams is / are connected between every two adjacent metallic vertical columns; each metallic cross beam is composed of a horizontal plate; a bar-shaped slot is formed in the horizontal plate at an inserting end of each metallic cross beam; each inserting clamping slot is arranged as a horizontal slot; a clamping strip is integrally formed in the middle of the bottom edge of each horizontal slot from bottom to top; the height of each clamping strip is less than the height of the corresponding horizontal slot; during an assembling process, the inserting clamping positioning of the horizontal plate at the grafting end of each metallic cross beam and the inserting clamping slot in the corresponding metallic vertical column is realized, each horizontal plate is inserted into the corresponding horizontal slot from a gap between the top edge of the corresponding clamping strip and the top edge of the horizontal slot, and the bar-shaped slot in each horizontal plate is aligned with the corresponding clamping strip and then is downward moved, clamped and positioned. The conveniently detached assembling flat plate type metal guard bar has the characteristics of firm structure, convenience in detaching, few parts, low cost, convenience in assembling and convenience in maintaining.

The invention relates to the field of chemical engineering, and discloses a steam generator blowdown apparatus. A plurality of auxiliary blow-off pipes (11) communicate with a main blow-off pipe (13)in a parallel connection mode. Each auxiliary blow-off pipe is provided with at least one pollutant absorption head (9). All the auxiliary blow-off pipes (11) are detachably fixed to T-shaped steel parts (12), and all the T-shaped steel parts are fixed to an inner side wall (7) of a steam generator. Each pollutant absorption head is in the shape of a gourd with a horn opening on the whole and is mainly composed of a horn-shaped pollutant absorption opening (18), a pollutant absorption narrow path (19), a loudbelly-shaped pollutant absorption cavity (20) and a threaded connector (23) which arein seamless connection in sequence. All the auxiliary blow-off pipes communicate with the pollutant absorption heads through pollutant absorption head connectors (24). One ends of the pollutant absorption head connectors are fixedly connected with the auxiliary blow-off pipes, and the other ends of the pollutant absorption head connectors are connected with the threaded connectors in a threaded mode. Compared with the prior art, the steam generator blowdown apparatus is even, reliable and efficient in pollutant discharging, discharging of non-dirty liquid can be effectively avoided, and the service life of the blow-off pipes is effectively prolonged.

The invention relates to a high-intensity magnetic field interference resisting system and method for an inspection robot, and the system comprises a hardware anti-electromagnetic interference device and a software anti-electromagnetic interference module, and the hardware anti-electromagnetic interference device comprises a drive board shielding case, a control chip shielding case, a robot shielding box body, an input signal isolation circuit, and a shielding wire rod. The software anti-electromagnetic interference module is used for reducing the use of while waiting statements in an algorithm, the control chip shielding case is wrapped by copper foil, and insulating layers are arranged on the inner side and the outer side of the control chip shielding case; the robot shielding box body is formed by welding aluminum plates; the input signal isolation circuit comprises an isolation diode and a peripheral circuit; the shielding wire rod is internally wrapped by a copper net. A hardware anti-interference mode and a software anti-interference mode are adopted, power grid spike pulse interference caused by a high-intensity magnetic field can be protected, and spike interference pulses generated by a power grid due to the high-intensity magnetic field can also be protected.

The invention discloses an intelligent parking space lock for an electric vehicle charging station and a preparation method thereof. The intelligent parking space lock comprises a charging pile, a parking space and a lock body, wherein the lock body is fixed to the parking space, a horizontal seat is fixed to the bottom of the lock body, the lock body is provided with a lock frame capable of beingpressed on the horizontal seat, the charging pile is installed on one side of the parking space, the lock frame is provided with a buffer mechanism, the buffer mechanism comprises a spring, a movableblock and a fixed groove, and the fixed groove is formed in the side surface of the lock frame. The intelligent parking space lock for the electric vehicle charging station and the preparation methodthereof have the beneficial effects that through the designed buffer mechanism, a buffering role is played when the lock is taken off the lock frame, and the service life of the lock frame is prolonged; through the designed fixed mechanism, the quick installation of the intelligent parking space lock is realized, and the intelligent parking space lock is further convenient to dissemble, repair and replace when the intelligent parking space lock is damaged; and the parking space is intelligently managed, information sharing of the parking space lock and the charging pile is realized, data information interconnection with the charging pile is effectively realized, the user experience is improved, and the utilization rate of the charging pile is increased.

The invention provides a mobile shared charge pal and advertisement promotion all-in-one machine for a shopping mall, and relates to the technical field of shopping mall display. The mobile shared power bank and advertisement promotion all-in-one machine for the shopping mall comprises a supporting body, a placement groove is formed in the lower portion of the front end face of the supporting body in a penetrating mode, a power bank cabinet is arranged in the placement groove, U-shaped frames are arranged at the rear ends of the two sides of the supporting body correspondingly, and motors are arranged on the inner sides of the upper ends of the U-shaped frames in a penetrating mode; a rotating rod is arranged at one end of the motor, a rotating block is arranged on the rotating rod in a penetrating mode, the rotating block is connected with the rotating rod, a supporting plate is arranged on the front end face of the rotating block, a base is fixedly connected to the lower end of the supporting body, an adjusting groove is formed in the lower end of the base in a penetrating mode, and an adjusting seat is arranged in the adjusting groove; and universal wheels are arranged on the periphery of the lower end of the adjusting seat. Through the device, integrated use of the power bank and advertisement promotion can be effectively realized.

The invention relates to the field of lamps, particularly to a novel fluorescent lamp structure. The novel fluorescent lamp structure comprises an outer cover and a lamp tube arranged inside the outer cover, two ends of the outer cover is provided with end covers, the outer cover is made of transparent plastics and comprises a straight portion and arc-shaped portions, the arc-shaped portions are connected with two sides of the straight portion in an integrally formed mode, the straight portion and the arc-shaped portions form a cover body with two ends opened, an reinforcing insertion groove is integrally formed along the inner wall of the straight portion, the inside of the outer cover is further provided with a substrate for mounting the lamp tube, reinforcing ribs are integrally formed on two sides of the inner walls of the arc-shaped portions, a substrate mounting insertion groove is formed between the reinforcing ribs, a mounting wing strip is integrally formed on two sides of the straight portion and extends outwards from the two sides of the straight portion, outer cover is further provided with a mounting plate which can be inserted onto the mounting wing strip, and the mounting plate is provided with insertion grooves corresponding to the mounting wing strip, and outer cover is further provided with a mounting plate which can be inserted into the mounting wing strip. The novel fluorescent lamp structure is convenient to install and dismantle, simple in replacement and maintenance and high in safety.

The invention discloses a control circuit board heat dissipation mounting box with a conveniently disassembled filter screen plate. The control circuit board heat dissipation mounting box comprises amain base plate and a mounting box body, wherein the top surface of the main base plate is fixedly connected with the mounting box body through bolts; the middle part of the mounting box body is provided with a middle mounting plate; the front wall surface and the rear wall surface of the middle mounting plate are fixedly connected onto the front wall plate and the rear wall plate of the mountingbox body through bolts; vertical plates are fixedly arranged on the left and right sides of the top surface of the middle mounting plate; a plurality of circulating ventilation fans are fixedly arranged on the outer side walls of the two vertical plates respectively; air outlets of the circulating ventilation fans face ventilation holes in the vertical plates; and an upper circulating ventilationfan is fixedly arranged at the bottom of the middle part of the top plate of the mounting box body. According to the control circuit board heat dissipation mounting box, the middle mounting plate is mounted inside the mounting box body, the circulating ventilation fans and the upper circulating ventilation fan are arranged on the middle mounting plate so as to realize rapid air inlet and air outlet inside the mounting box body, the heat dissipation effect is good, the efficiency is high, simultaneously, the control circuit board heat dissipation mounting box is provided with the filter screenplate capable of preventing dust and sundries, and the filter screen plate is convenient to disassemble, change and maintain.

The invention relates to a production process for producing uranium trioxide by utilizing a fluidized bed denitration technology, in particular relates to a device for feeding a uranyl nitrate hexahydrate (UNH) solution in the process, and relates to an atomization nozzle joint. When an atomization nozzle of a denitration fluidized bed is designed, a pyrolysis denitration condition of the UNH solution is sufficiently considered, fault points are reasonably avoided and the design is reasonable. The front end of the nozzle is leveled with a reactor wall; under the condition of properly controlling a gas-liquid ratio, a condition that the UNH solution flows off along a furnace wall to cause material sintering basically does not occur. A gas phase and a liquid phase of the atomization nozzle are separately designed and are only crossed at the nozzle; pressure of atomized gas is greater than pressure of fluidized gas; hot gas cannot enter a nozzle space to be subjected to pyrolysis denitration and the nozzle is not blocked. Actual application shows that the atomization nozzle is stable and safe in operation and has good continuous operation performance.

The invention discloses a carbon fiber production process capable of simultaneously carrying out washing and sizing treatment, and particularly relates to the technical field of carbon fiber production. The carbon fiber production process specifically comprises the following steps of S1, yarn withdrawing, yarn collecting and drying treatment, S2, pre-oxidation carbonization treatment, and then machining surface treatment, and S3, washing, drying, sizing, re-drying treatment and yarn collecting. The invention relates to the technical field of carbon fiber production. According to the carbon fiber production process capable of simultaneously carrying out washing and sizing treatment, washing and sizing treatment procedures can be combined for simultaneous treatment, the purpose of conveniently and efficiently carrying out washing and sizing treatment on carbon fibers is well achieved, the production efficiency is greatly improved, the workload of production personnel is relieved, the site space is saved, a large number of rollers do not need to be adopted to widen the line width, the cost is low, the side-by-side design is well adopted to save more space, the water washing cost is reduced through the water washing pool bottom winding design, and therefore use by people is greatly facilitated.

The invention discloses a brush type sealing structure allowing a rotor to reverse. The brush type sealing structure comprises a stator, a brush type sealing part, pawls, spiral springs and the rotor,wherein the stator is annular, the inner circumference of the stator is sawtooth, and the brush type sealing part is arranged in the stator in a clearance fit manner; the brush type sealing part comprises a front baffle, a connecting area, a rear baffle and a brush wire strand, the front baffle, the connecting area, the rear baffle and the brush wire strand are integrally connected, the brush wire strand is clamped between the front baffle and the rear baffle, one end of the brush wire strand is fixedly connected with the connecting area, and the other end of the brush wire strand is obliquely arranged in the rotation direction of the rotor; arc grooves are uniformly formed in the periphery of the connecting area, one ends of the pawls are arranged in the arc grooves through pawl shafts,and the other ends of the pawls are inserted into tooth grooves of the inner circumference of the stator in coordination manner; and the spiral springs are arranged between the pawls and the brush type sealing part in a compression manner. In the case of rotor reversal, the brush type sealing structure can still guarantee that the brush wire strand is in a perfect condition, the service life of brush wires is prolonged, and the use cost of the brush wires is reduced.

The invention discloses a three-dimensional luminophor lamp which adopts light-transmitting materials for heat conduction, heat dissipation and sealing and is high in luminous flux, uniform in light color distribution, capable of achieving full-circumference light emitting, safe and reliable, and a manufacturing method thereof. The three-dimensional luminophor lamp adopting the light-transmitting materials for heat conduction and heat dissipation comprises electric outgoing lines, heat-conduction light-transmitting bodies, at least one light-emitting source, a driver and an electric connector, wherein each heat-conduction light-transmitting body is provided with at least one groove or at least one boss, and the light-emitting sources are arranged in the grooves or on the bosses; electrodes at the two ends of each light-emitting source are connected with the corresponding electric outgoing lines, and the electric outgoing lines are connected with the driver and connected with an external power source through the electric connector; and the light-emitting sources are sealed through the heat-conduction light-transmitting body II, and the light-emitting sources sealed in the heat-conduction light-transmitting body at least partially make contact with the heat-conduction light-transmitting body or the heat-conduction light-transmitting body II directly or through transparent dielectric layers and / or luminescent powder layers. The three-dimensional luminophor lamp has higher power, can output high luminous flux and is higher in reliability.

The invention discloses a fish breeding tank with a filtering and cleaning function. The fish breeding tank comprises a fish breeding tank body, a water inlet is formed in the inner wall of the top side of the fish breeding tank body in the vertical direction, positioning holes are formed in the inner wall of one side of the water inlet in the horizontal direction, a positioning rod is movably mounted in the positioning holes, the two ends of the positioning rod extend out of the positioning holes, movable grooves are formed in the inner wall of the bottom sides of the positioning holes in thevertical direction, pulling rods are movably mounted in the movable grooves, and the tops of the pulling rods extend out of the movable grooves. According to the fish breeding tank, water addition can be automatically stopped after water is added into the fish breeding tank, and the situation is avoided that too much water is added and the environment in the fish breeding tank body is damaged; through the arrangement of a cleaning frame, the fish breeding tank body is convenient to clean, and meanwhile a filtering core plate is convenient to detach, maintain and replace; the water quality inthe fish breeding tank body is ensured, the fish breeding tank body is more convenient to use, and the demands of people are met.

The invention relates to the technical field of an apparatus for a spectrometer, in particular to a single-board lens structure. The single-board lens structure is simple, convenient to install and debug, and easy to disassemble, replace and maintain, and comprises a front lens frame and a back lens frame which cooperate with each other. A lens projection block is arranged on the head of the front lens rack and a circular positioning block is arranged on the end. A front through hole penetrating through the front lens rack is arranged in the middle of the front lens structure. A front screw hole and a nut hole are arranged in the edge of the lens projection block. A circular positioning groove matched with the circular positioning block is arranged in the head of the back lens rack. A lens installation groove is arranged in the circular positioning groove. A lens camera is arranged in the lens installation groove. A back through hole which penetrates through the back lens rack and corresponds to the front through hole is arranged in the middle of the back lens rack. A gap is arranged in the side part of the lens installation groove. A back screw hole cooperating with the front screw hole is arranged in the back lens rack. The front lens rack is fixedly connected with the back lens rack through a screw and a nut.