719 results about "Smoke hood" patented technology

The invention discloses an anomaly diagnosis method and system based on a chain grate-rotary kiln pellet roasting temperature prediction model and a storage. According to the method, process detection parameters such as the thickness of a material layer of a chain grate machine, the temperature of a smoke hood of a preheating section, the coal injection amount of a main burner and the temperature of a kiln head of a rotary kiln serve as input, the pellet roasting temperature is predicted in advance through a prediction model constructed based on an XGBoost algorithm, and then the contribution size and direction of all the parameters to roasting temperature abnormity are determined through SHAP value analysis. According to the method, advanced information can be provided for production regulation and control, the hysteresis quality of traditional actual measurement analysis is overcome, meanwhile, key influence factors causing temperature abnormity are rapidly positioned, and accurate regulation and control are guided. The abnormality diagnosis system developed based on the method can improve the pellet production stability, the product quality and the production efficiency, reduces the production cost and the energy consumption, and plays an important guiding role in the intelligent production of the chain grate-rotary kiln oxidized pellets in the ferrous metallurgy field.

The invention provides an intelligent copper blowing system based on multi-modal sensing. The intelligent copper blowing system comprises a multi-modal sensing system, an intelligent decision and control module, a real-time simulation system, an air supply system and a flexible sealing smoke hood. The multi-mode sensing system collects melt components in the furnace, temperature field distribution, equipment operation states and environmental pollutant concentration data in real time. And the intelligent decision and control module predicts a flow field and pollutant diffusion path through a real-time simulation system based on the sensing data, and generates a dynamic control instruction. The air supply system adjusts the blast pressure and the oxygen concentration according to instructions, the flexible sealing smoke hood dynamically adjusts the expansion amount of the sealing apron board, and smoke leakage is restrained. The smelting efficiency can be improved, pollutant emission is reduced, and the service life of equipment is prolonged.

The utility model discloses a kitchen stove with a waste heat recovery system, a chimney cap is fixedly connected to the rear side of the top end of a cooking bench, the chimney cap is communicated with the interior of the cooking bench through a combustion exhaust flue, and the waste heat recovery system comprises a first waste heat recovery pipeline and / or a second waste heat recovery pipeline arranged on the first waste heat recovery pipeline and / or the second waste heat recovery pipeline; the first waste heat recovery pipeline comprises a cooking bench pipeline arranged in a cooking bench and / or a chimney cap pipeline arranged in a chimney cap; the circulating water tank communicates with the first waste heat recovery pipeline and / or the second waste heat recovery pipeline through a circulating water pipeline. The first waste heat recovery pipeline and the second waste heat recovery pipeline are arranged, waste heat of the cooking bench and the smoke exhaust hood is recovered through the circulating water pipeline by means of water, the water returns to the circulating water tank after absorbing heat, and waste heat of the kitchen cooking range is recovered and utilized through hot water heated by the circulating water tank.

The invention provides a glass fabric cutting device which comprises a cutting table and a portal frame with a lifting function, and the cutting table is located on the lower portion of a cross beam of the portal frame. A cutting unit is arranged on a cross beam of the portal frame and comprises an exhaust fume collecting hood, a sliding rail, a laser generator, an air compressor, an air inlet pipe, a cyclone barrel, an exhaust pipe, a scrap outlet and a scrap collecting box. The exhaust fume collecting hood is fixed to the bottom of a cross beam of the portal frame. The sliding rail is fixed into the exhaust fume collecting hood. Negative pressure adsorption is formed through the exhaust fume collecting hood and the air compressor, high-temperature smoke dust and glass fiber chippings generated in the cutting process are rapidly sucked in, the cyclone barrel is introduced, the smoke dust and the solid chippings are effectively separated through the cyclone separation technology, it is ensured that the working environment is clean, and the influence on the health of operators is reduced. Meanwhile, the scrap collecting box is combined with the pasting roll and the display board to adhere solid scraps, automatic winding operation of the scraps is achieved through the rotating motor, the cleaning process is simplified, and efficiency is improved.

The utility model provides a dust removal exhaust fume collecting hood, and belongs to the technical field of exhaust fume hoods. The dust removal exhaust fume collecting hood comprises an exhaust fume collecting hood body and a translation adjusting mechanism, a fume opening is formed in the bottom of the exhaust fume collecting hood body, a connecting pipe communicated with the fume opening is installed at the top of the exhaust fume collecting hood body, a translation cavity is formed in the exhaust fume collecting hood body, and translation plates are movably connected to the two sides of the interior of the translation cavity; a contact groove is formed in the inner side of the translation plate and makes contact with the surface of the connecting pipe, the outer side of the translation plate is fixedly connected with a peripheral plate, and the connecting shell is movably connected to the front side of the exhaust fume collecting hood body. A medium for horizontally moving and adjusting the smoke collecting range of the smoke collecting hood body according to the actual smoke collecting requirement is provided for a user, the situation that the smoke collecting range is difficult to adjust when the smoke collecting hood body is used is avoided, and therefore the using adaptability and flexibility of the smoke collecting hood body are improved.

The utility model discloses an automatic cleaning type smoke hood all-in-one machine which comprises a shell, and an air inlet and an air outlet are formed in the shell. The cleaning structure is arranged in the shell, the cleaning structure comprises a conveying header pipe for conveying steam, a rotating shaft rotatably connected with the conveying header pipe, a connecting pipe communicated with the rotating shaft and a steam spray head communicated with the connecting pipe, and the steam spray head sprays the steam towards the purification assembly; the purification assembly is arranged in the shell and is used for purifying oil fume; oil smoke enters the shell from the air inlet, is purified by the purification assembly and then is discharged from the air outlet.

1. Name of the product in this design: Smoker (KZ-32). 2. Purpose of this design product: used for smoking food. 3. The key design feature of this product is its shape. 4. The image or photograph that best illustrates the design's key points: a 3D model.

The invention discloses a method for improving coal gas recovery quality through dry dedusting, which comprises the following steps: S1, setting and dynamically adjusting the rotating speed parameter of a fan aiming at each stage of converter smelting, and controlling the fan to operate according to different operation links and blowing time periods in the smelting process and the set rotating speed parameter and time parameter; s2, raw material preparation and parameter regulation and control are carried out, components, temperature and charging quantity parameters of molten iron entering a furnace are set and controlled, and meanwhile the charging quantity and charging mode parameters of waste steel are set and regulated and controlled; s3, according to the silicon element content of the molten iron, correspondingly setting and controlling a furnace mouth micro differential pressure parameter; s4, in the main blowing smelting stage, oxygen supply flow parameters are matched, set and controlled according to the silicon element content of the molten iron; s5, auxiliary control parameter setting and measures are implemented, wherein the auxiliary control parameters comprise a smoke hood operation control parameter, an evaporative cooling system medium adjustment parameter, a gas recovery program optimization parameter and a fan rotating speed control mode configuration parameter; and S6, after smelting is finished, the recovery average value of CO in the coal gas is recorded. According to the method for improving the coal gas recovery quality through dry dedusting, the average CO value of coal gas recovery is larger than or equal to 55%, the heat value is high, the coal gas quality is stably improved during continuous production of a converter, and the cost reduction and efficiency improvement effects are obvious.

According to the multifunctional integrated oven trolley, fuel gas is adopted as energy, smoke generated in the barbecuing process can be reduced, no charcoal ash is left, and cleaning and maintaining are convenient; the multiple straight pipe furnace ends can be independently controlled, a user can adjust fire power according to requirements, gas consumption is reduced, the overall temperature control precision is improved, and partition temperature control is supported; the movable cabinet body is convenient to move, and food materials are convenient to stack due to the arrangement of the storage table; through the design of the exhaust fume collecting hood and the exhaust fume extraction device, exhaust fume gas generated in the barbecue process can be extracted, meanwhile, after the hood body rotates upwards by 90 degrees to be opened, some scattered exhaust fume can enter the main fume suction channel of the exhaust fume collecting hood along the auxiliary fume suction channel and the auxiliary fume suction opening, and due to the fact that the coverage range of the hood body is large, the range of the hood body is large. The range of suction of the spilled oil smoke is larger, so that the spilled oil smoke gas is further sucked, and finally, the oil smoke gas subjected to concentrated suction can be matched with a related oil smoke purifier for purification treatment.

The utility model relates to a range hood. The range hood comprises an exhaust fume collecting hood, an oil cup and a first oil guide plate, the exhaust fume collecting hood comprises a panel, a front plate and a back plate, wherein the front plate and the back plate are arranged above the panel at intervals; an upper air inlet is formed by the panel and the front plate; the first oil guide plate is connected with the front plate and arranged at the upper air inlet, and the rear end of the first oil guide plate obliquely extends downwards relative to the back plate, extends into the exhaust fume collecting hood and is located on the rear side of the top end of the panel. Oil dirt generated by the upper air inlet in the oil fume suction and discharge process is guided by the first oil guide plate to smoothly fall into the exhaust fume collecting hood and finally enters the oil cup, so that the oil dirt on the first oil guide plate can be effectively prevented from falling out of the exhaust fume collecting hood, and the problem that oil marks are generated by the upper air inlet in the oil fume suction and discharge process can be solved; and moreover, fewer parts are adopted, the structure is simple, the assembly is easy, the cost is lower, and the product performance is improved.

The application discloses a heat pipe heat sink welding process based on heat conduction and belongs to the technical field of welding. The welding equipment is composed of a vacuum box, a control box, an electromagnetic device, a heating plate, a control box, a vacuum straight-through pipe with a water cooling jacket, a water pipe, a vacuum variable-diameter cross pipe, a gas release valve, a vacuum valve, a condenser, a vacuum bellows, a vacuum pump, a baffle valve, a gas collecting pipe, a smoke hood, a liquid cooling source and a smoke purifier. The application has the advantages that the problems of product performance decline and even scrapping caused by the floating of the heat pipe in the traditional welding process are perfectly solved, the welding quality is improved, the vacuum pump is protected and the service life of the vacuum pump is prolonged, the process is simple and easy to implement, and the production cost can be greatly reduced.

The invention relates to the technical field of smelting devices, and provides a direct-current submerged arc furnace for smelting, which comprises an operation platform, an electric furnace body, a low smoke hood type furnace cover, a guide rack, a rectifier transformer, a direct-current power supply, a cooling water system and a hydraulic station, and is characterized in that the low smoke hood type furnace cover is erected and mounted at the upper end of the electric furnace body; the low smoke hood type furnace cover is composed of a side wall and a top cover, a graphite electrode clamp is arranged above the low smoke hood type furnace cover, the graphite electrode clamp comprises a connecting shaft, the upper end of the connecting shaft is fixedly connected with the guide rack, and a sliding rod is vertically installed at the upper end of the connecting shaft. An original alternating-current submerged arc furnace holder system is omitted, the electric arc furnace type conductive cross arm stand column is adopted for lifting, lifting is stable, the lifting speed is adjustable and controllable, a traditional alternating-current transformer is designed into a rectifier transformer and a direct-current power source, main electric energy is provided, electric energy loss is reduced, and the effects of saving smelting cost and reducing power grid impact are achieved.

The invention belongs to the field of industrial silicon submerged arc furnace smelting, and provides a closed industrial silicon submerged arc furnace which comprises a submerged arc furnace body, a supporting platform is arranged above the furnace body, and a discharging uniform distribution device, a flue gas emission system, an electrode operation system, a feed system and a two-dimensional space movement furnace ramming device are arranged above the supporting platform. A water-cooling closed smoke hood is fixed below the supporting platform, a furnace charge preheating device is arranged at the top end in the water-cooling closed smoke hood, a three-dimensional space movement furnace ramming device, an electrode operation visible system and an explosion-proof device are arranged on the side part of the water-cooling closed smoke hood, and an oxygen blowing refining device and a continuous silicon discharging device are arranged on the side part of the furnace body; and a furnace body rotating system is also arranged at the bottom of the furnace body. The problems that the industrial silicon submerged arc furnace is high in energy consumption, large in emission, low in efficiency and the like in the smelting operation process are solved, and the beneficial effects of low consumption, less emission, zero emission and the like are achieved.

The utility model relates to the technical field of extractor hoods, in particular to an exhaust fume collecting hood smoke barrier and an extractor hood. The smoke collecting hood smoke barrier comprises a smoke barrier body and a flow guide part. The front side of the smoke barrier body faces the smoke inlet of the smoke collecting hood, and airflow turns at the front end of the smoke barrier body when entering the smoke collecting hood through the smoke inlet. The flow guide part is arranged on the side, facing the interior of the smoke collecting hood, of the smoke barrier body, a flow guide face is formed on the side, deviating from the smoke barrier body, of the flow guide part, the edge of one side of the flow guide face extends to the edge of the front side of the smoke barrier body, and the other side of the flow guide face extends towards the rear side of the smoke collecting hood and gradually inclines upwards. Therefore, when passing through the front side of the smoke barrier main body and turning backwards, the airflow flows along the flow guide surface which is inclined upwards, so that the turning direction of the airflow is guided through the flow guide surface, airflow turbulence caused by low-speed eddy current formed at the front end of the smoke barrier main body when the airflow turns is avoided, and the smoke suction effect of the range hood is ensured; and abnormal sound is avoided.

The utility model discloses a noise reduction type integrated cooker which comprises a cooker body and an exhaust fume collecting hood arranged on the cooker body, an exhaust fume inlet is formed in the exhaust fume collecting hood, spoilers are arranged in an air duct cavity of the exhaust fume collecting hood, and the spoilers comprise the first spoiler and the second spoiler; a through outlet is formed in the bottom end of the exhaust fume collecting hood and defined by the side edge of the bottom of the exhaust fume collecting hood. The spoiler is arranged in the air duct cavity, an airflow path is optimized, airflow flows around the spoiler and flows along the middle of the head instead of being originally close to the rear side wall of the air duct cavity, friction between the airflow and the rear side wall of the air duct cavity is reduced, the flow speed of the airflow is increased, turbulence energy is reduced, the smoke suction efficiency is improved, noise is effectively reduced, and the smoke suction efficiency is improved. Meanwhile, the through outlet in the bottom end of the exhaust fume collecting hood is directly defined by the side edges of the bottom end of the exhaust fume collecting hood, the cross section of the through outlet is directly a through groove and is in through connection with the air duct cavity, the section change rate of the exhaust fume outlet end of the exhaust fume collecting hood is reduced, and therefore air duct system resistance and noise can be effectively reduced.

The utility model belongs to the technical field of high-rise building fire-fighting equipment detection, and particularly relates to a high-rise building fire-fighting equipment detection device, which comprises a smoke hood, the bottom of the smoke hood is in threaded connection with a circular-truncated-cone-shaped bottom-layer protective cover, a plurality of uniformly distributed air inlet holes are formed in the circumferential side wall of the bottom-layer protective cover, and a fan is mounted in an inner cavity of the bottom-layer protective cover; the overall size of the device is small, fire fighting detection is conducted on a smoke alarm by means of the multiple detection mechanisms at the top of the device body, detection personnel can conveniently hold the device body by arranging the first butt joint rod, the fan is arranged and arranged under the smoke generator, and the detection efficiency is improved by arranging the first butt joint rod and the second butt joint rod. The smoke is quickly blown away by using wind generated when the fan works, so that residual smoke in the bottom of the bottom plate, the inner cavity of the displacement cavity and the inner cavity of the hollow interlayer of the diffusion head can be quickly discharged under the action of the wind generated when the fan works, time is greatly saved for subsequent detection, and the overall detection effect of the device is improved.

The utility model belongs to the technical field of hot water equipment, and particularly discloses a testing tool which comprises an exhaust fume collecting hood, a flue gas sampling tube and a flue gas sensor, the exhaust fume collecting hood is provided with a fume inlet facing the combustor, and the exhaust fume collecting hood is provided with a plurality of installation structures. The flue gas sampling pipe is provided with a sampling hole, and the flue gas sampling pipe can be mounted on any mounting structure and conduct flue gas to the flue gas sensor; and when the smoke sampling pipe traverses the mounting structure, the sampling hole can traverse all fire holes of the combustor. According to the testing tool, by changing the position of the flue gas sampling pipe in the exhaust fume collecting hood, the flue gas values of the flue gas discharged from the fire holes at different positions in the combustor can be detected respectively, so that whether primary air or secondary air distribution of the combustor is reasonable or not is judged; and the improvement on the structures of the primary air hole and the secondary air hole of the gas water heater is facilitated.

The invention provides an intelligent fireproof and high-temperature steam cleaning oil fume integrated hood, and relates to the technical field of range hoods, and the intelligent fireproof and high-temperature steam cleaning oil fume integrated hood comprises an oil fume diffusion monitoring module used for obtaining an oil fume image; through a difference image method, according to the difference between the oil smoke image and the reference image, obtaining oil smoke diffusion data; vOC data are obtained; calculating a lampblack diffusion quantized value; the intelligent cleaning module is used for determining the optimal steam release temperature and the optimal steam release amount through an improved artificial neural network; according to the optimal steam release temperature and the optimal steam release amount, the steam release amount and temperature of the range hood are dynamically adjusted based on a PID control system of a radial basis function neural network, and the smoke hood is cleaned by releasing high-temperature steam; the flame monitoring module is used for acquiring a cooking bench image through a camera; through a convolutional neural network, identifying a flame combustion degree, and determining a kitchen fire occurrence probability value; and the fire extinguishing module is used for spraying water to extinguish the kitchen.

The invention discloses a forming and welding device and method for an oil screen and a smoke hood of a range hood, and particularly relates to the technical field of welding, the forming and welding device for the oil screen and the smoke hood of the range hood comprises a welding base, and further comprises a central stand column which is vertically arranged at the center of the welding base, and a plurality of splicing units are arranged on the periphery of the central stand column in a circular array mode. Under the control of the first adjusting part of the adjusting unit, the limiting part acts to clamp and limit the side plate of the smoke hood, the second adjusting part is synchronously linked for control, the second adjusting part cooperatively controls the splicing units to be close to each other and gather together to splice the smoke hood into a whole, the construction technology is optimized, and the construction efficiency is improved. According to the welding device, repeated debugging and assembling of workers are not needed, under the control of the adjusting unit, clamping, positioning and synchronous splicing operation of all the smoke hood side plates can be synchronously completed, the overall production efficiency is improved, welding consistency is guaranteed, and the overall welding quality is synchronously improved.

The invention discloses a novel heating control mode for a thermal deaerator of a converter flue gas waste heat boiler, which relates to the technical field of waste heat boiler equipment and comprises the following main steps of inspection before operation, water feeding operation, heating preparation, heating control, operation monitoring and heating ending and shutdown. Parameters such as water level, water replenishing quantity, a regulating valve, temperature detection and a flow meter are controlled through the deaerator, heat of circulating return water of a movable smoke hood, an oxygen lance opening and a discharging opening of the boiler and cooling water quantity during water replenishing of the deaerator are calculated, temperature rise of added soft water is calculated, and meanwhile, a PLC program is matched, so that the temperature of the boiler is increased. According to the method, the water supplementing amount during smelting and the steam heating amount of water supplementing in the non-smelting period are automatically controlled, a heating adjusting valve and a water supplementing adjusting valve of the deoxygenization water device are controlled, temperature control over the deoxygenization device is achieved, the deoxygenization device reaches the optimal deoxygenization temperature, and the problem that the optimal deoxygenization temperature cannot be guaranteed due to the discontinuity of converter steelmaking is solved.

The invention discloses a flue gas treatment control method for an intelligent commercial UV smoke hood, and relates to the field of flue gas treatment control of UV smoke hoods, and the flue gas treatment control method comprises the following steps: emitting interference sound waves on the upper layer of a smoke hood filter screen to generate a standing wave field, and carrying out secondary filtration on grease particles in flue gas based on a standing wave effect; analyzing the physical characteristics and mechanical characteristics of the grease particles in the standing wave field, and calculating the expected penetration rate of the grease particles in the flue gas in the secondary filtering process; based on the expected penetration rate of grease particles in the secondary filtering process, the UV illumination intensity is dynamically adjusted in combination with the flue gas flow rate; the variety and content of by-product gas in the flue gas after UV illumination treatment are analyzed, and the adaptability of the UV illumination intensity after adjustment is evaluated; and setting a UV illumination intensity secondary adjustment scale based on the UV illumination intensity suitability, and circularly adjusting the UV illumination intensity until the UV illumination intensity suitability reaches a set standard.

The invention belongs to the technical field of smelting mechanical equipment, and particularly relates to a direct-current submerged arc furnace and a smoke hood thereof.The direct-current submerged arc furnace comprises a smoke hood body, an exhaust pipe is fixedly connected to the interior of the smoke hood body, a filter plate is slidably connected to one end of the exhaust pipe, and a fixing plate is arranged on one side of the filter plate; the fixing plates are fixedly connected with the inner wall of the smoke hood body, a moving frame is slidably connected between the fixing plates, a fixing block is fixedly connected to the upper surface of the moving frame, a moving block is arranged on one side of the fixing block, and the moving block is slidably connected with the inner wall of the moving frame. According to the invention, the fixed block and the movable block are arranged to reciprocate below the filter plate, so that stove ash accumulated below the filter plate can be cleaned, and the stove ash cannot be accumulated on the filter plate, so that the filter plate is kept clean and works efficiently, and the problem that the filter plate is blocked by the stove ash is avoided.

The utility model discloses a flame cutting auxiliary device which comprises a slag water tank, a filter plate is arranged in the slag water tank, lifting mechanisms are arranged on the two sides of the upper end of the slag water tank, a smoke dust collecting mechanism is arranged on the slag water tank, each lifting mechanism comprises a rolling wheel base, a rolling wheel is arranged in the rolling wheel base, and a smoke dust collecting mechanism is arranged on the smoke dust collecting mechanism. A winding wheel is arranged on the base, a winding rope is wound on the winding wheel, one end of the winding wheel is connected with a motor, and the smoke dust collecting mechanism comprises a first smoke collecting hood, a second smoke collecting hood, a smoke dust collecting box and a filtering box; according to the flame cutting auxiliary mechanism, the slag water tank, the filter plate, the lifting mechanism and the smoke dust collecting mechanism jointly form the flame cutting auxiliary mechanism, a large amount of slag generated in the flame cutting process is received through the slag water tank and cooled and collected, follow-up slag recycling treatment is facilitated, smoke dust is collected through the smoke dust collecting mechanism, and the smoke dust collecting efficiency is improved. The filtered airflow is discharged through a pipeline, so that the workshop environment is prevented from being polluted by smoke dust, and the influence on other equipment is avoided.

The present application relates to a kind of smelting smoke cover auxiliary plate control method, device, equipment and medium, including according to smoke cover auxiliary plate in different historical smelting furnace power deformation, temperature and airflow field, through the mapping of smoke cover temperature field, smoke cover airflow field and smoke cover stress field by the simulation of multiple physical field coupling, construct digital twin three-dimensional dynamic model;Temperature, airflow intensity and the deformation degree of auxiliary plate key area in the temperature of smoke cover auxiliary plate in smelting process are input into digital twin three-dimensional dynamic model, and the predicted surface temperature distribution, the predicted flue gas component concentration and the predicted smelting furnace power are obtained;According to true smelting power and predicted smelting furnace power, determine the correction combination parameter value, according to the correction combination parameter value, correct the predicted surface temperature distribution and the predicted flue gas component concentration to obtain target surface temperature distribution and target flue gas component concentration;According to target surface temperature distribution and target flue gas component concentration, generate control parameter, according to control parameter control auxiliary plate opening degree.

The invention discloses a wet-type film forming structure and a wet-type fire-retardant smoke hood all-in-one machine with the same. The wet-type film forming structure comprises a pore plate assembly and a water circulation device for conveying water to the pore plate assembly. The pore plate assembly comprises a lower pore plate and an upper pore plate, and lampblack sequentially penetrates through the lower pore plate and the upper pore plate; the water circulation device continuously conveys water to the lower pore plate and forms a water film on the lower pore plate, the thickness of the water film is set to be 8-12 mm, and the flow speed of the oil fume penetrating through the lower pore plate is 8-12 m / s; saturated oil fume gas is in contact with the upper pore plate for cooling and water removal after being in contact with the water film of the lower pore plate for cooling and filtering, the lower pore plate and the upper pore plate are arranged, so that the oil fume purification effect is better, and meanwhile, the water circulation device is arranged to convey water to the lower pore plate and form the water film, so that the oil fume can be in contact with water all the time, and the oil fume is cleaned and cooled.

The utility model provides an exhaust fume collecting hood and gas water heating equipment comprising the exhaust fume collecting hood. The smoke collecting hood comprises a hood shell used for collecting smoke, a smoke exhaust pipe extending upwards from the hood shell, and a baffle assembly fixedly contained in the smoke exhaust pipe. The baffle assembly comprises a support fixedly installed in the smoke exhaust pipe, a rotating shaft arranged on the support and a pair of baffles which are arranged on the rotating shaft in a pivoted mode and can be opened and closed. The support is further provided with a limiting piece which extends upwards and abuts against the pair of baffles when the pair of baffles are clamped so as to limit the minimum clamping angle between the pair of baffles. By arranging the limiting piece, the baffle cannot cross the rotating shaft to be overlapped with the baffle on the other side after being blown up, and therefore the baffle can smoothly fall back to the original closing position.

The range hood comprises a first shell, a second shell and an exhaust fume collecting hood, the periphery of the second shell is at least partially coated with the first shell, at least part of the first shell is located below the second shell, and the first shell can do up-and-down lifting motion relative to the second shell; a control panel is arranged on the front side of the first shell, the distance between the front side of the first shell and the front side of the second shell is smaller than the thickness of the part, located in the first shell, of the control panel, so that the control panel is kept below the second shell when the first shell ascends and descends, and the exhaust fume collecting hood is arranged on the first shell; the distance of the exhaust fume collecting hood extending forwards out of the front side of the first shell is a1, the vertical distance from the operation center of the control panel to the top face of the exhaust fume collecting hood is b2, the included angle between the connecting line from the operation center of the control panel to the front side of the exhaust fume collecting hood and the vertical direction is delta, tan delta = a1 / b2, a1 is larger than or equal to 0 mm, and delta is smaller than or equal to 40 degrees.

The embodiment of the utility model discloses an exhaust fume collecting hood assembly and a range hood, the exhaust fume collecting hood assembly comprises an exhaust fume collecting hood and a detection device; the exhaust fume collecting hood is provided with a mounting cavity; the detection device comprises a shell assembly and a detection assembly, one part of the shell assembly is located in the mounting cavity and fixedly connected with the exhaust fume collecting hood, the other part of the shell assembly is located outside the mounting cavity, and the detection assembly is arranged in the shell assembly and used for collecting temperature and / or concentration and correspondingly adjusting the working state of the extractor hood. The shell assembly in the exhaust fume collecting hood assembly can play a role in protecting the detection assembly, so that the problem that oil stains, oil fume, water vapor and the like make contact with the detection assembly, and consequently the detection assembly is damaged is solved, meanwhile, the shell assembly is partially embedded and fixed in the mounting cavity, the connection firmness between the shell assembly and the exhaust fume collecting hood is improved, and the service life of the exhaust fume collecting hood assembly is prolonged. Therefore, the connection firmness between the detection assembly and the exhaust fume collecting hood is improved, and the detection reliability of the detection device is further ensured.