84results about How to "Large range of protection" patented technology

The invention relates to a high-voltage safety linkage protect system, wherein it combines hardware and control software, uses program control; its hardware comprises key box, grounding switch and high- voltage locks on devices, which are connected via the software interface to form the high- voltage safety linkage protect system, to realize inter-lock via keys. And the invention comprises following program that: a, when reaching the high-voltage device, it uses hardware interlock and control software, to avoid lifting electric arc and closing the main breaker; b, when reaching the high-voltage device, the vehicle circuit is grounded; c, when powering the vehicle, the power connector is cut off, to improve the safety, and using the hardware feedback signal to detect the system and realize intelligent display function.

The invention discloses a solid corrosion and scale inhibitor for an oil field, which relates to the technical field of chemical medicine reagents used for the oil field. The solid corrosion and scale inhibitor comprises the following ingredients: 2-phosphonic acid butane 1, 2, 4-tricarboxylic acid PBTCA, polyethyleneglycol, sodium hexametahposphate, span-60 and stearic acid, wherein each ingredient accounts for the mass percent of the sum of all the ingredients as follow: 30 percent to 40 percent of 2-phosphonic acid butane 1, 2, 4-tricarboxylic acid PBTCA, 10 percent to 15 percent of polyethyleneglycol, 10 percent to 15 percent of sodium hexametahposphate, 15 to 25 percent of span-60 and 20 percent to 30 percent of stearic acid. The invention is particularly suitable for well tubes of oil-gas wells with server corrosion and scale conditions, and has good corrosion and scale inhibition effects on underground pipe posts and equipment.

The invention discloses a filming corrosion inhibitor, which at least comprises 30 to 50 percent of octadecylamine, 20 to 30 percent of imidazoline amide, and reducing agent carbohydrazide being the rest, the above proportion is mass percentage. Under the condition that the temperature is 150 to 500 DEG C, the concentration of the filming corrosion inhibitor is 10 to 35 ppm, the pH valve is 7 to 11, and the time duration is 1 h to 10 min, the filming corrosion inhibitor can produce a compact protective film on the metal surface, and the function of preventing the metal to be corroded in the atmospheric environment is realized, especially the invention can be applied during the thermal power plant to stop the boilers for protection, the protective film with strong hydrophobicity and good erosion resistance can be produced on the metal surface inside the water vapor system of the thermal equipment, and the thermal equipment can be protect from being corroded for more than 8 months during the exposition in atmospheric environment, simultaneously, the invention has certain cleaning, uncovering, and removing function to the incrustation and the corrosion product on the metal surface of the thermal system, the probability of the thermal equipment corrosion and the four-tube blasting is reduced, the invention is advantageous for extending the acid pickling cycle of the boiler, the service life of the equipment is prolonged, the security is enhanced, and the economic benefit is increased.

The invention discloses a high-speed railway supply arm shunt tripping protection method based on impedance characteristics. The method is realized through impedance protection elements distributed in a substation, an AT station and a subarea station in a scattered mode and through a communication network, wherein the quadrangular operation characteristics are adopted for the impedance protection elements. Each impedance protection element can transmit shunt tripping instructions to other impedance protection elements or receive the shunt tripping instructions from other impedance protection elements on the same supply arm through the communication network to rapidly isolate a fault supply arm. The impedance protection elements of the substation and the impedance protection elements of the AT station jointly protect all power supply sections between the substation and the AT station. The impedance protection elements of the AT station and the impedance protection elements of the subarea station jointly protect all power supply sections between the AT station and the subarea station. When a fault of any impedance protection element is detected, a breaker of the fault supply arm in the station is tripped off, a shunt tripping instruction is transmitted to the other impedance protection elements on the same supply arm, the other impedance protection elements receive the shunt tripping instruction and then trip off the corresponding breakers, and consequently the fault supply arm is rapidly isolated, and power supply of the other supply arm which is connected with the fault supply arm in parallel can not be influenced.

A method for protecting a metal surface against corrosion and scaling is provided, which comprises connecting individual two ends of a metal piece (1) to be protected with an AC power supply (2) and allowing the current density of the metal piece at least 0.5A / m<2>. An apparatus for implementing the method comprises an oscillator, a driver circuit and an inverter, wherein the signals from oscillator are input to the driver circuit and the driver circuit drives the inverter. Under the skin effect of high-frequency current in the metal piece, a large quantity of free electrons are concentrated on the surface of the metal piece, and the electrons have negative charges and repulse oxidative anions, thereby providing anti-corrosive and anti-scaling effects. The method is suitable for the corrosion and scaling protection of ship, offshore oil-drilling platform, oil and chemical pipeline, metal container and equipment, boiler, air conditioner, engine and bridge. The invention aims to provide a method protecting a metal surface against corrosion and scaling without reconstructing the existing equipment and structure and superior in low cost, wide protection range, uniform protection and good protective effect.

The present invention discloses an information processing apparatus and method based on a patent group. The method comprises: receiving information input by a user; according to the information input by the user, generating a search formula to search for a field range corresponding to the information input by the user, and storing a file that is obtained through searching; performing semantic analysis on each file that is obtained through searching, to obtain a keyword list of each file; storing a reference keyword list, wherein the reference keyword list corresponds to the field range; and performing file group analysis on a file obtained through searching by a comparative file generation unit, to generate a file group cluster result, and then according to the file group cluster result, the obtained keyword list of each file by an analysis unit and the reference keyword list, obtaining a score value. During file group analysis, quantity or file network analysis is performed on the file group clusters of personnel of the same type, and during the analysis, all files in the field range related to what the user inputs are analyzed, so that the value of the files can be evaluated easily by referring to file group information.

The invention discloses a transformer fault detection method. The method based on a transformer electrical parameter fault feature library includes transformer model building, transformer electrical parameter fault feature library establishment and fault detection. The method is implemented in an all-digital manner, various transformer faults such as external open circuit fault, internal open circuit fault, to-earth short-circuit fault, turn-earth short-circuit fault, turn-to-turn short-circuit fault, external phase fault and internal phase fault can be judged accurately, and proper expansion can be performed according to actual demand. The method is widely applicable to transformers such as oil immersed transformers, water cooled transformers, air cooled transformers and air and water cooled transformers, occurrence of the transformer faults is prevented and judged to the uttermost extent, the technical problems about parameter detection, fault protection and fault diagnosis are solved, safety and maintainability of the system are improved, and difficulty and consumed time for system troubleshooting are lowered.

The invention discloses a chicken egg-yolk antibody capable of resisting influenza virus. The chicken egg-yolk antibody is used for specifically resisting tetravalence influenza virus. The influenza virus includes influenza A virus subtype H1N1, influenza A virus subtype H3N2, influenza B virus subtype Victoria series and influenza A virus subtype Yamagata series. The preparation method of the chicken egg-yolk antibody comprises the following steps of 1, preparing a tetravalence influenza virus antigen; 2, performing immunity on hens; 3, collecting immunized eggs laid by the immunized hens; 4, preparing a mixed antibody stock solution from the immunized eggs; 5, detecting titer of the antibody stock solution, and a stabilizer is added cooperatively, so that the chicken egg-yolk antibody capable of resisting tetravalence influenza virus is obtained. The chicken egg-yolk antibody can be combined with the tetravalence influenza virus specificity pathogen for a short period of time, the tetravalence influenza virus can be effectively killed for a long period of time, the safety performance is good, no toxic or side effect is generated, and the chicken egg-yolk antibody can be effectively used for preventing pathogen corresponding to human pharyngeal and nasopharynx mucosas.

The invention discloses a method for screening candidate bacterial strains from fish streptococcus agalactiae vaccines. The method comprises the steps: separation and breed conservation of tilapia streptococcicosis agalactiae epidemic strains, identification of the epidemic strains and the establishing of a pathogenic library, PFGE genotype analysis of epidemic strains, toxicity determination of PFGE genotype representative strains, and immunogenicity and protection domain test of the PFGE genotype representative strains so as to obtain a candidate bacterial strains combination of a tilapia streptococcicosis agalactiae immunoprophylaxis vaccine in China. The technology has the characterizes of strong pertinence, high screening efficiency, remarkable effect and the like, and the screen candidate bacterial strains combination of the tilapia streptococcosis agalactiae immunoprophylaxis vaccine in China can protect 90% of genotypes and 96.47% of epidemic strains in the pathogenic library. The technology provides a new method for screening the candidate bacterial strains from the fish streptococcus agalactiae vaccines, is suitable for screening the candidate bacterial strains from the fish streptococcus agalactiae vaccines, and has significance and using value in immune prevention and control on fish streptococcicosis.

The invention discloses a preparation method of a solid corrosion-inhibition scale-inhibition bar used for an oil field, which relates to a production method of a chemical medicament used for the oil field. The preparation method comprises the following steps of: (1) mixing 30 to 40 percent of 2-phosphonobutane-1,2,4-tricarboxylic acid, 10 to 15 percent of polyethylene glycol, 10 to 15 percent of sodium hexametaphosphate, 15 to 25 percent of Span-60 and 20 to 30 percent of stearic acid evenly, wherein the percent is the mass percent of the sum of each component occupying all the components; and (2) putting all the evenly mixed components into a bar type mold, pressing into a bar type by using a press machine and forming a finished product, wherein the pressure applied by the press machine is 15 to 20 tons. The method has the advantages of simple preparation process, even mixing of the components, trouble saving and labor saving, so that the method is suitable for mass and industrialized production and large-scale popularization and application.

The invention discloses a portable electric power and power grid overhead line construction and maintenance protection device. The portable electric power and power grid overhead line construction and maintenance protection device comprises a conductor grip upper frame (1), a first conductor grip lower frame (2), a second conductor grip lower frame (3), a first connecting rope (4), a connecting device (5), a third connecting rope (6), a belt device (7), a fourth connecting rope (8) and a protection plate device (9). The portable electric power and power grid overhead line construction and maintenance protection device is good in protection effect, a protection device at the lower end can be folded, the device is convenient for electric power maintenance workers to carry about during line maintenance, and the maintenance workers conveniently climb pylons up and down, so that the operation difficulty is reduced, and the overall work efficiency is improved; the operation is more convenient; the stability and adaptability are high, and different construction environments can be met; the operation process is simple, meanwhile the overall protection range is wide, and the safety factor is high; and the device can be stably fixed on a line, and also has a good wind prevention effect.

The invention provides a switch cabinet outlet device, which includes a sealing cover, a dustproof plug, a torsion spring, a rotating shaft, a sleeve, a chute, a slider and a wire protection sleeve. The sealing cover is installed on the annular side of the rotating shaft, and the dustproof plug is installed on the The middle position of the lower end face of the sealing cover, the rotating shaft is installed at the lower part of the rear end face of the switch cabinet body, and the rotating shaft is connected with the switch cabinet body through a torsion spring. This design realizes the automatic sealing function, good sealing effect, good dustproof effect, and the sleeve is fixed At the lower part of the rear end surface of the switchgear body, the chute is set on the inner annular side of the sleeve, the slider is fixed on the annular side of the grommet, and the slider is assembled in the chute, and the grommet is installed in the sleeve. The design realizes the protection function of the circuit, is convenient for operators to adjust, and has a wide protection range. The invention has reasonable structure, good sealing performance, good protection performance, long service life and high reliability.

The invention discloses a protection method of a super-long-period shut-down thermal generator set, which comprises the following steps: 1. preparing an octadecylamine emulsion; 2. adding the octadecylamine emulsion; 3. preparing an ammonia-diammonium protection solution; 4. adding the ammonia-diammonium protection solution; and 5. putting silica gel, inspecting and treating the color change and replacing the colloid every 7-10 days, and determining the change of the inspection period. The method has the advantages of favorable film-forming effect and wide film-forming protection range; the thermal generator set is maintained sectionally, so the effect is better; the method is suitable for the maintenance of the thermal generator set which has been continuously shut down for more than half a year to one year; the invention greatly shortens the vapor quality qualification time when starting the thermal generator set, saves abundant water and coal, and has obvious economic benefit; and the invention does not need to greatly reconstruct the original pipeline, and therefore, has the advantages of simple technique, easy operation and high safety.

The invention relates to a rockfall buffering flexible protection system, which belongs to the technical field of slope protection systems. The falling stone buffering flexible protection system can provide larger displacement freedom degree for falling stone, reduce impact load of the falling stone, control bouncing height of the falling stone and guide motion trails of the falling stone. The function is that the falling rock interception area of the system is used for attenuating the falling rock kinetic energy from the uphill surface, controlling the falling rock motion trail, and guiding the falling rock motion trail into the falling rock buffering channel at the tail section of the system, so that the falling rock is continuously guided downwards under the constraint effect of the falling rock buffering channel until entering the falling rock accumulation area. The protection system guides falling rocks from an upper slope to a slope toe or a downhill section for centralized accumulation and cleaning, or enables the falling rocks to enter a next protection structure with relatively small kinetic energy and bounce height, so that the falling rocks with relatively high kinetic energy can be protected with relatively low protection energy level and system height.

The invention relates to an anti-corrosion communication iron tower comprising a tower body, a platform, a lightning rod, a plurality of antennas, a plurality of supporting feet and a plurality of protective devices. Each protective device comprises a fixing plate and four protective mechanisms. Each protective mechanism comprises a hinging assembly, a protective plate, a rainproof film, a drivingassembly and a vibration assembly. Each vibration assembly comprises a first motor, a bearing, a first driving shaft, an eccentric wheel and two fixing rods. Each driving assembly comprises a horizontal-moving unit, an air pump, an air cylinder and two extending units. According to the anti-corrosion communication iron tower, the periphery of the tower body is protected through the protective mechanisms, during raining, the rainproof films are expanded on the sides, away from the tower body, of the protective plates through the driving assemblies, and rainwater is prevented from falling ontothe tower body to corrode the tower body through the protective plates and the rainproof films; and not only that, during snowing, the protective plates swing to remove accumulated snow on the protective plates through the vibration assemblies, fracturing of the protective plates is avoided, thus equipment is protected for safe operation, and the practicality of the communication iron tower is improved.

The invention relates to a five-prevention system for an intelligent substation. The five-prevention system is positioned in a monitoring system of the intelligent substation and is connected with an intelligent terminal and terminal equipment of the intelligent substation respectively. The five-prevention system comprises a monitoring-system background locking module, a spacing-layer locking module and an electric-loop locking module; the monitoring-system background locking module is connected with a monitoring database in the monitoring system and the electric-loop locking module respectively; the spacing-layer locking module is connected with the intelligent terminal; and the electric-loop locking module is connected with the terminal equipment. Compared with the prior art, the five-prevention system has the advantages of high informationization degree, convenience in remote-control operation and high safety performance and the like.

The invention discloses a wheel spraying protection device. The wheel spraying protection device consists of a hollow mounting frame (1), an electric cylinder (2), a tray (3), an electromagnetic sucker (4), a sleeve (5), a piston (6), a soft rubber cover (7), a support column (8), an end cover (9), a high-temperature resisting plastic protection plug (10), a spring (11) and an iron column (12). The wheel spraying protection device can achieve a protection effect in the wheel paint spraying process, and solves the problem of attaching paint on flange surfaces, center holes and conical surfacesof bolt holes. The device has the characteristics of advanced process, easy manufacturing, simple structure, powerful functions and the like.

The invention provides a preparation method of a tetravalent influenza virus split vaccine. The method comprises the following steps: 1) preparation of a harvesting liquid; 2) virus inactivation; 3) ultrafiltration and concentration; 4) first purifying after the concentration; 5) second purifying; 6) virus lysis; 7) third purifying after the lysis; 8) preparation of a semi-finished product; and 9)preparation of a finished product. The method has the technical effects that the method has the following technical effects: a tetravalent influenza virus split vaccine sample prepared by an optimized three-step purification process has lower ovalbumin content, lower impure protein content and high-purity hemagglutinin antigen, so that the adverse reaction of the tetravalent influenza virus splitvaccine is lower, the immune effect of the vaccine is better, and the safety of the vaccine is higher.

The invention discloses a multifunctional shielding composite material with air permeability and a preparation method thereof. Specifically, the invention provides the multifunctional shielding composite material which is high in protection performance, good in air permeability and comfortable to wear and the preparation method of the multifunctional shielding composite material. The multifunctional shielding composite material is formed by compounding at least four layers of materials with different functions from inside to outside: an innermost layer is a unidirectional moisture-conducting non-woven layer; a second layer is a lead-free X / gamma ray shielding material composite foaming layer or a lead-free X / gamma ray shielding material composite fiber non-woven layer; a third layer is anelectromagnetic shielding composite foaming layer or an electromagnetic shielding composite non-woven layer; and an outermost layer is a three-proofing breathable non-woven layer.

The invention provides a group A, group B and group C meningococcus combined vaccine which is composed of polysaccharide-protein conjugates and a group B ST-4821 genotype (xrsw341215) meningococcus outer membrane protein vesicle (OMV), wherein the polysaccharide-protein conjugates are obtained in a manner that a group A meningococcus capsular polysaccharide and a group C meningococcus capsular polysaccharide are each subjected to covalent binding with a group B serotype 4-type (CMCC29356) meningococcus outer membrane protein vesicle (OMV). The vaccine can simultaneously prevent group A, group B and group C meningococcus invasive diseases, has better protective effects especially on prevention aiming at epidemic cerebrospinal meningitis high-risk groups at the age of less than 2 years, and moreover, has better specificity and better protection effect aiming at nature group A, group B and group C meningococcus invasion.

The invention discloses an emergency risk avoiding device for a highway bridge, and belongs to the technical field of highway bridge safety facilities. The emergency risk avoiding device for the highway bridge comprises a highway body, a baffle is arranged on the front side of the highway body, fixing plates are welded to the left end and the right end of the baffle, containing grooves are formed in the front sides of the fixing plates, rotating plates are arranged in the containing grooves, extending plates are sleeved with the upper ends of the rotating plates, and a plurality of containing grooves are formed in the inner walls of the rear sides of the containing grooves in a linear structure. A limiting assembly is arranged on the top face of the fixing plate in a penetrating mode, a transmission assembly is arranged on the front side of the upper end of the highway body, a steel wire mesh A is arranged on the rotating plate, and when a vehicle collides with a guardrail on the roadside, the rotating plate can form a certain included angle under the pulling force of the steel wire rope, so that a pocket is formed between the steel wire mesh A and the baffle, the falling vehicle can be held, and thus the vehicle is prevented from directly falling to the valley bottom, the safety of the vehicle and personnel is ensured, and the device plays a role of emergency risk avoiding.

The invention provides a rubber material for a sealing rubber strip, and belongs to the technical field of sealing rubber strips. The invention provides the rubber material for the sealing rubber strip. The rubber material comprises the following components in parts by weight: 140-200 parts of oil-extended ethylene propylene diene monomer, 1-10 parts of zinc oxide, 1-5 parts of stearic acid, 1-5 parts of an anti-aging agent, 1-5 parts of protective wax, 2-10 parts of an active agent, 60-200 parts of a reinforcing filler, 40-100 parts of paraffin oil and 2-5 parts of a vulcanizing agent. The oil-extended ethylene propylene diene monomer is used, high filling is achieved under the condition that a small amount of operating oil is added, the processability is good, and the using amount of theoperating oil and the hardness of the rubber material for the sealing rubber strip are both considered.

The invention relates to a dengue virus degeneration vaccine and application thereof. The amino acid sequence of the dengue virus degeneration vaccine is shown as SEQ ID NO.2; the amino acid sequence of the dengue virus degeneration vaccine contains an antigen peptide fragment, a dengue virus envelope glycoprotein EDIII region, a virus virulence related gene neutralizing epitope, a beta lamella and Loop amino acid, wherein the antigen peptide fragment is determined after sequence comparison analysis is carried out on a dengue virus representative strain which respectively contains serotypes 1,2,3,4; and the beta lamella retains a basic structure which forms the dengue virus envelope glycoprotein EDIII region. The dengue virus degeneration vaccine disclosed by the invention can be used for immunizing an organism, stimulating the organism to generate humoral immunity response and preventing the dengue virus infectious diseases.

The invention discloses a method for screening candidate bacterial strains from fish streptococcus agalactiae vaccines. The method comprises the steps: separation and breed conservation of tilapia streptococcicosis agalactiae epidemic strains, identification of the epidemic strains and the establishing of a pathogenic library, PFGE genotype analysis of epidemic strains, toxicity determination of PFGE genotype representative strains, and immunogenicity and protection domain test of the PFGE genotype representative strains so as to obtain a candidate bacterial strains combination of a tilapia streptococcicosis agalactiae immunoprophylaxis vaccine in China. The technology has the characterizes of strong pertinence, high screening efficiency, remarkable effect and the like, and the screen candidate bacterial strains combination of the tilapia streptococcosis agalactiae immunoprophylaxis vaccine in China can protect 90% of genotypes and 96.47% of epidemic strains in the pathogenic library. The technology provides a new method for screening the candidate bacterial strains from the fish streptococcus agalactiae vaccines, is suitable for screening the candidate bacterial strains from the fish streptococcus agalactiae vaccines, and has significance and using value in immune prevention and control on fish streptococcicosis.

The invention discloses an application of a low-melting-point flux to large-power TIG welding joint protection. The low-melting-point flux comprises, by mass, 20-30 parts of Al2O3, 15-25 parts of TiO2, 10-15 parts of CaO, 10-15 parts of NaCl, 5-10 parts of MgO, 5-10 parts of V2O5, 3-5 parts of potassium fluoborate and 3-5 parts of MnO. All the components are placed in a mortar to be fully and evenly ground, and the particle sizes of all the raw materials range from 200 meshes to 800 meshes. After covering a high-temperature solidified welding joint, the low-melting-point flux is molten and rapidly lubricates the welding joint, the surface of the welding joint is completely covered, a protective film is formed, in this way, the welding joint is prevented from being oxidized, the mechanical performance and corrosion resistance of the welding joint are improved, the formed welding joint is attractive, and it is only required that simple slag removal treatment is conducted after welding.

The invention discloses a binding tape with a disposable password protection function and relates to the binding tape. The binding tape with the disposable password protection function comprises at least one binding tape and a password binding tape body for using a disposable password to unidirectionally lock the binding tape, wherein the password binding tape body comprises a box body, a password disk group arranged in the box body and at least one elastic part. The elastic part is used for unidirectionally locking or releasing the password lock sheet corresponding to the binding tape and continuously exerting acting force toward one direction to push the password lock sheet under control of the password disk group. Each password disk of the password disk group is provided with a locking mechanism corresponding to the password lock sheet, and the password lock sheet is locked with each password disk under the pushing of the elastic part when each password disk is rotated to a password position, and meanwhile, the password lock sheet is unlocked with the binding tape. The binding tape with the disposable password protection function is disposable after password protection locking.

The invention discloses a low-melting point welding flux applicable to the protection of a high-power TIG (Tungsten Inert Gas) welding seam, which comprises the following main components in part by mass: 20-30 parts of Al2O3, 15-25 parts of TiO2, 10-15 parts of CaO, 10-15 parts of NaCl, 5-10 parts of MgO, 5-10 parts of V2O5, 3-5 parts of KBF and 3-5 parts of MnO; all the components are put into a mortar to be fully and uniformly ground; and the granularity of all materials is between 200-800 meshes. The low-melting point welding flux has the benefits that the low-melting point welding flux can be molten after being covered on the surface of the high-temperature solidified welding seam and quickly moisturized to the welding seam, and can be completely covered on the surface of the welding seam to form a protective film layer, so that the oxidation of the welding seam is prevented, and the mechanical property and the corrosion resistance of the welding seam are improved; and the welding seam is attractive in appearance after being formed and is subjected to simple slag removal after being welded.

The invention discloses an intelligent control system of transformers and coolers based on comprehensive perception and a working method thereof. Equipment operating conditions are comprehensively judged according to multi-information of the transformers and the coolers, a reliable identification method is provided for equipment states, real-time monitoring, early warning and evaluation of a wholecooling system are realized, and intelligent management of cooler operation is realized. According to the intelligent control system of the transformers and the coolers based on the comprehensive perception, feed-through transformers and air switches are arranged on connecting circuits of a power supply I, a power supply II and a bus bar; air switches are arranged on connection circuits of the bus bar and the coolers; the connection circuits of the bus bar and the coolers include main circuits and two branch circuits connected in parallel on the main circuits; air switches are installed on the main circuits, feed-through transformers are arranged on the two branch circuits correspondingly connected with an oil pump and a fan; and a transformer and cooler intelligent control device is further included, and the transformer and cooler intelligent control device comprises a central MCU, multiple sampling circuits and multiple voltage transformers.

The invention discloses a nested air bag safety helmet which comprises a helmet housing and an inferior frontal belt (7) and is characterized in that the helmet housing adopts an air bag framework; the air bag framework is a nested air bag; the nested air bag comprises an external air bag (12) and an internal air bag (16); the internal air bag (16) is embedded into the external air bag (12); an internal wall (1) of the external air bag (12) is connected with a helmet tension band (4) via a plastic bracket (3); and the helmet tension band (4) is connected with a cross girdle (9), the inferior frontal belt (7) and a rear hoop (6). The nested air bag safety helmet solves the technical problems that a wearer is uncomfortable due to large mass of the safety helmet, the safety helmet is not designed with a brim structure and cannot protect body sites such as an after brain, ears and a face, and the number of holes in the helmet housing and hole diameters are small in order to ensure firmness of the safety helmet resulting in low air permeability in the prior art.