CN109595633B - Fume exhauster - Google Patents

Abstract

The invention discloses a range hood, which comprises a fume collecting hood, a case arranged above the fume collecting hood and a fan system arranged in the case, wherein an air inlet is formed in the fume collecting hood, an air duct is formed in the case, the fan system comprises a first ternary fan and a second ternary fan which are arranged in parallel, a filter screen is arranged at the bottom of the case and at the inlet of the air duct, the filter screen comprises a filter screen body which is in an inverted cone shape with a small upper part and a big lower part, and meshes are densely distributed on the filter screen body. By arranging the upwards concave inverted cone-shaped filter screen, the distance between the filter screen and the fan can be shortened, and the filter screen is close to a strong negative pressure area, so that when oil fume enters, the filter screen is directly subjected to the strong negative pressure, thereby greatly improving the air suction effect, ensuring that the air inlet on a flow field is smooth, avoiding the suction force of the range hood and avoiding the phenomena of more oil fume leakage and suction leakage; the filter screen is low in lower periphery and high in middle, so that the oil fume is concentrated during absorption, and the collection efficiency of the oil stains can be improved; the smoke is collected deeply, and the oil smoke is absorbed deeply without blocking.

Description

Fume exhauster

Technical Field

The invention relates to kitchen appliances, in particular to a range hood.

Background

The range hood has become one of the indispensable kitchen appliances in modern families. The conventional range hood comprises a top suction type range hood and a near suction type range hood, wherein the top suction type range hood utilizes the principle of rising hot air to suck and discharge the naturally rising oil smoke generated during cooking, and has wider and wider application due to the advantages of neatness, light weight, small occupied space and the like.

The conventional range hood is provided with a filter screen for collecting oil smoke, smoke dust and the like generated during cooking, and a smoke guide plate for preventing the oil smoke from escaping. The top-suction type range hood with the smoke guide plate disclosed in China patent application No. 201420478328.X comprises a smoke collecting cover and a smoke guide plate, wherein an air inlet is formed in the smoke collecting cover, the smoke guide plate is opposite to the air inlet of the smoke collecting cover, a smoke exhaust channel is formed by keeping a preset distance between the smoke guide plate and the smoke collecting cover, an oil net is further arranged at the air inlet of the smoke collecting cover, the oil net is fixed at the air inlet of the smoke collecting cover through a buckle or a screw, and the smoke guide plate is positioned below the oil net; as another example, a range hood with an adjustable air inlet surface is disclosed in chinese patent with application number 201410443175.X, and comprises a wind cabinet and a fume collecting hood arranged at the bottom of the wind cabinet, wherein the wind cabinet comprises a frame and a host which is arranged in the frame and can be lifted along the frame, the host comprises a body with a square cross section and a turbo fan arranged in the body, the periphery of the body is closed, a conical net cover is arranged at the bottom opening of the body, and an oil cup is arranged at the bottom of the conical net cover; as disclosed in the chinese patent with application number 201610642513.1, the bionic filter screen is disposed at the smoke cage of the lower end of the main machine of the range hood, and is located at the air inlet of the upper end of the oil cup, the fan system with the air outlet is installed in the main machine, and the bionic filter screen is a thin metal shell of a cone, a rectangular cone or a square cone with a big top and a small bottom, or a big top and a big bottom.

Foretell range hood, the smoke guide plate that sets up in range hood's air intake department is the platykurtic, and the smoke guide plate can't play the effect of drainage, acceleration to the oil smoke, is difficult to effectively promote the oil smoke effect, and the rectification board relative position is fixed moreover, and the negative pressure district can not be adjusted according to the service condition of top of a kitchen range. The oil net is generally in a flat or downward convex funnel shape, and the flat oil net is not suitable for the characteristic of multiple oily foods in the pot and is easy to drip; the funnel-shaped oil net is fixed at the bottom of the range hood and protrudes downwards, the oil fume is divergent when being collected, the fume is shallow, the oil fume cannot be deeply absorbed and is far away from a negative pressure area of the fan, the fume suction effect is affected, and in addition, when a user uses the range hood, the user has visual sense to press, the sight is blocked during cooking, the user is easy to touch the oil net when the user turns over a pan to cook, and the cooking experience of the user is reduced; in addition, when the funnel-shaped oil net is adopted, the smoke exhaust ventilator cannot be provided with the smoke guide plate.

Disclosure of Invention

The invention aims to solve the technical problems of the prior art and provides a range hood capable of improving the oil fume suction efficiency and the oil and fat separation effect.

The technical scheme adopted for solving the technical problems is as follows: the utility model provides a range hood, includes collection petticoat pipe, sets up the quick-witted case and the fan system of setting in quick-witted incasement of collection petticoat pipe top, set up the air intake on the collection petticoat pipe, the machine incasement is formed with wind channel, its characterized in that: the fan system comprises a first ternary fan and a second ternary fan which are arranged in parallel, a filter screen is arranged at the bottom of the machine box and at the inlet of the air duct, the filter screen comprises a filter screen body which is in an inverted conical shape and is small in upper part and large in lower part, and meshes are densely distributed on the filter screen body.

For the grease of being convenient for collect quick-witted case, fan and filter screen self, the edge of filter screen body outwards extends and is formed with annular oil trap, the outward flange of oil trap extends to the bottom of quick-witted case outward to upwards buckle.

In order to accelerate the flow rate of the oil smoke and improve the oil smoke absorption efficiency, a smoke guide plate is arranged below the air inlet, and at least one part of the lower surface of the smoke guide plate gradually inclines upwards from the middle to the edge, thereby being matched with the corresponding wall surface of the fume collecting hood to define an accelerating flow passage with the cross section gradually reduced from bottom to top.

Preferably, for effectively accelerating the lampblack around the smoke guide plate, the lower surface of the smoke guide plate comprises at least one of a first inclined plane, a second inclined plane and a third inclined plane, the first inclined plane is inclined upwards from the middle to the left side and forms a first accelerating flow channel with the left side plate of the smoke collecting hood, the second inclined plane is inclined upwards from the middle to the right side and forms a second accelerating flow channel with the right side plate of the smoke collecting hood, and the third inclined plane is inclined from the middle to the front side and forms a third accelerating flow channel with the front side plate of the smoke collecting hood.

Further, in order to facilitate the installation of the smoke guide plate, four corners of the upper surface of the smoke guide plate are respectively provided with a connecting column, and the connecting columns are connected to the outer edge of the air inlet of the smoke collecting hood, so that the smoke guide plate is connected with the smoke collecting hood.

In order to enable the smoke guide plate to be capable of adjusting the height according to the size of the oil smoke so as to better improve the oil smoke suction effect, the smoke guide plate can be lifted to the highest position to close the air inlet when the range hood is closed, the oil smoke backflow of a public flue is avoided, and the connecting column is a telescopic rod driven by a motor.

For on the basis of not changing the machine case size, increase the amount of wind, first ternary fan includes first ternary impeller and first air intake, the ternary fan of second includes second ternary impeller and second air intake, on the oil smoke flow path, second air intake is equal with first air intake position, first air intake and second air intake set up side by side to the left and right sides of quick-witted case respectively.

Preferably, in order to reduce wind resistance and improve the oil fume absorbing effect on the premise of not increasing the size of the case, the first ternary impeller of the first ternary fan and the second ternary impeller of the second ternary fan respectively form 60-90 degrees with the horizontal direction, and the two ternary impellers incline towards opposite directions.

According to one aspect of the invention, the first ternary fan further comprises a first volute, the first ternary impeller is arranged in the first volute, the second ternary fan further comprises a second volute, the second ternary impeller is arranged in the second volute, the first volute and the second volute are arranged at intervals and side by side, the first air inlet is formed in the first volute, the second air inlet is formed in the second volute, a first oil smoke channel is formed in the first volute, a first air outlet is formed at the top end of the first oil smoke channel, a second oil smoke channel is formed in the second volute, and a second air outlet is formed at the top end of the second oil smoke channel.

According to another aspect of the invention, the first ternary impeller and the second ternary impeller are arranged at intervals and side by side in the same volute, a first air inlet corresponding to the first ternary impeller and a second air inlet corresponding to the second ternary impeller are respectively formed at two opposite sides of the volute, a mounting plate is arranged between the first ternary impeller and the second ternary impeller and extends to the top end of the volute, so that the interior of the volute is divided into two independent first oil smoke channels and second oil smoke channels, the top end of each first oil smoke channel forms a first air outlet, and the top end of each second oil smoke channel forms a second air outlet.

In order to drive two impellers simultaneously, the device further comprises a driving motor arranged between the first ternary impeller and the second ternary impeller, and the driving motor is provided with double output shafts for driving the first ternary impeller and the second ternary impeller respectively.

For playing the water conservancy diversion effect to the gas of the corresponding export of two ternary fans, be favorable to the outlet gas to form laminar flow to reduce flow loss by a wide margin, raise the efficiency, fan system's air outlet department is provided with the air-out cover, the air-out cover is including being the cover body of cavity tube-shape, the cover body has relative, open-ended first end and second end, the bore of first end is greater than the bore of second end, its characterized in that: the novel three-dimensional air diffuser is characterized in that a first guide plate and a second guide plate are arranged in the cover body, each guide plate extends from the first end of the cover body to the second end, a first diffusion flow passage is formed between the first guide plate and the inner side wall of the cover body, a second diffusion flow passage is formed between the second guide plate and the inner side wall of the cover body, the sectional areas of the first diffusion flow passage and the second diffusion flow passage are gradually reduced from the first end of the cover body to the second end of the cover body respectively, the first diffusion flow passage corresponds to the first air outlet of the first three-dimensional air blower at the first end of the cover body, and the second diffusion flow passage corresponds to the second air outlet of the second three-dimensional air blower at the first end of the cover body.

In order to reduce outlet noise, sound absorption holes are densely distributed on the first guide plate and/or the second guide plate.

Compared with the prior art, the invention has the advantages that: by arranging the upwards concave inverted cone-shaped filter screen, the distance between the filter screen and the fan can be shortened, and the filter screen is close to a strong negative pressure area, so that when oil smoke enters, the filter screen is directly subjected to the strong negative pressure, and the air suction effect is greatly improved; by arranging the smoke guide plate with the inclined lower surface and forming the oil smoke accelerating flow channel together with the smoke collecting cover, the amount of oil smoke entering the range hood in unit time can be increased, and the oil smoke absorbing effect is improved; through the upwards concave inverted cone-shaped filter screen and the smoke guide plate with the inclined lower surface, when the oil smoke ascending airflow passes through the smoke guide plate, a separation vortex can be generated, the sudden drop of the fluid speed caused by sudden expansion can be slowed down, the negative pressure and loss at the turning position are reduced, the downwards convex smoke guide plate and the upwards convex oil net form a small-periphery and large-middle flow passage, so that the smoke collection is deeper, the volume of the oil smoke cage smoke is increased, the oil smoke gas is collected, the contact area of the oil smoke and the oil net is also increased, the filtering effect is improved, the oil and fat separation degree is improved, the inlet strong negative pressure effect of the three-way fan is also fully exerted, the internal air vortex effect is reduced, and the air flow noise is reduced by reducing the turbulence; because ternary fan import department negative pressure is great, and traditional oil screen cloth mode's central authorities area has the oil cup, can interfere the formation of negative pressure and oil smoke absorption effect, and the reversal oil screen need not set up the oil cup in central authorities area, only needs to connect oil in peripheral region, is favorable to the strong negative pressure effect of performance ternary fan more, and the reversal is arranged and is favorable to the oil smoke to accelerate moreover, and oil smoke absorption effect is good.

Drawings

Fig. 1 is a schematic view of a first embodiment of a range hood according to the present invention;

fig. 2 is a front cross-sectional view of the range hood of fig. 1;

fig. 3 is a side sectional view of the range hood of fig. 1;

fig. 4 is a schematic view of a smoke guide plate of the range hood of fig. 1;

fig. 5 is a schematic view of a filter screen of the range hood according to the present invention;

fig. 6 is a cross-sectional view of a fan system of the range hood of fig. 1;

fig. 7 is a schematic view of an air outlet cover of the range hood of fig. 1;

FIG. 8 is a schematic view of a second embodiment of a fan system of the extractor hood of the present invention;

fig. 9 is a cross-sectional view of a second embodiment of a fan system of the range hood of the present invention.

Detailed Description

The invention is described in further detail below with reference to the embodiments of the drawings.

Example 1

Referring to fig. 1 to 3, the range hood comprises a fume collecting hood 1 and a case 2 arranged above the fume collecting hood 1, wherein a fan system 4 is arranged in the case 2. The fume collecting hood 1 is provided with an air inlet 11, so that the fan system 4 in the case 2 can suck fume, enter the case 2 through the air inlet 11 and then are discharged to a public flue.

The chassis 2 includes a left side wall 21, a right side wall 22, a front side wall 23 and a rear side wall 24, and the cavity between the side walls forms an air duct 25 for the fume flow, and the air duct 25 preferably tapers from bottom to top.

In this embodiment, the fan system 4 is a three-way fan, and the three-way fan may be a three-way fan according to the prior art, as disclosed in chinese patent No. 201310418009. The fan system 4 can be a single ternary fan, two ternary fans connected in parallel or two ternary fans connected in series, and the ternary fans have the characteristics of compact structure, relatively small size, high fan efficiency and high wind pressure, so that the negative pressure gradient can be generated, and the smoking efficiency can be greatly improved. The specific structure of the fan system 4 will be described in detail below. An air outlet cover 5 connected with an air outlet of the fan system 4 is arranged above the case 2, so that the oil smoke can be discharged into a public flue through the air outlet cover 5.

An upwardly concave smoke collecting cavity 12 is formed in the smoke collecting cover 1, an air inlet 11 is positioned at the top of the smoke collecting cavity 12, a smoke guide plate 8 is arranged in the smoke collecting cavity 12 and at a position opposite to the air inlet 11, and condensation and filtration treatment is carried out on the smoke before the smoke enters the smoke exhauster through the smoke guide plate 8, so that the first smoke separation is carried out. With reference to fig. 5, the shape and size of the smoke-guiding plate 8 substantially coincides with the cross-section of the smoke-collecting chamber 12.

At least a portion of the lower surface of the smoke guide plate 8 is inclined gradually upwards from the middle to the edge, thereby defining an accelerating flow path with a gradually decreasing cross section from bottom to top in cooperation with the corresponding wall surface of the smoke collecting hood 1. When the oil smoke flows from bottom to top to contact with the lower surface of the smoke guide plate 8, the oil smoke is guided to split in the horizontal direction by utilizing the coanda effect, then guided into the acceleration flow channel from the edge of the smoke guide plate 8, flows upwards into a cavity formed between the upper surface of the smoke guide plate 8 and the smoke collecting cover 1, and finally enters the chassis 2 through the air inlet 11.

Because the cross section of the accelerating flow channel is gradually reduced from bottom to top, the flow speed is continuously increased after the oil fume enters the accelerating flow channel, and the suction force of the oil fume is correspondingly increased, so that the oil fume can quickly enter the machine case 2 to be separated, and the oil fume suction amount in unit time of the range hood is further improved.

Referring to fig. 4, the lower surface of the smoke guide plate 8 may be entirely inclined, or may be partially inclined or partially flat. The inclined surface may be an inclined plane or an arc surface. In the present embodiment, the lower surface of the smoke guide plate 8 includes at least one of a first inclined surface 81, a second inclined surface 82 and a third inclined surface 83, wherein the first inclined surface 81 is inclined upward from the middle to the left side, a first accelerating flow path 84 is formed between the first inclined surface 81 and the left side plate 13 of the smoke collecting hood 1, the second inclined surface 82 is inclined upward from the middle to the right side, a second accelerating flow path 85 is formed between the second inclined surface 82 and the right side plate 14 of the smoke collecting hood 1, the third inclined surface 83 is inclined toward the front from the middle, and a third accelerating flow path 86 is formed between the third inclined surface 83 and the front side plate 15 of the smoke collecting hood 1. The inclined surfaces constitute the complete lower surface of the smoke guide plate 8. The inner surfaces (surfaces facing the inside of the smoke collecting chamber 12) of the left side plate 13, the right side plate 14, and the front side plate 15 may be inclined surfaces that gradually incline inward from bottom to top.

Therefore, the drainage and acceleration of the lampblack are realized by arranging the acceleration flow channel between the fume collecting hood 1 and the fume guide plate 8, so that the fume sucking quantity of the range hood in unit time is improved. The smoke guide plate 8 is combined with the fan system 4, so that the effect of fume suction can be further remarkably improved due to the characteristics of the ternary fan.

The four corners of smoke guide plate 8 upper surface are provided with spliced pole 87 respectively, be connected to the outward flange of air intake 11 of collection petticoat pipe 1, thereby be connected smoke guide plate 8 and collection petticoat pipe 1, spliced pole 87 can be fixed member, also can be by motor drive's telescopic link, the telescopic link can adopt prior art, thereby smoke guide plate 8 can be according to the size height-adjusting of oil smoke, in order to improve the oil smoke effect better, simultaneously when the range hood is closed, smoke guide plate 8 can rise to the highest position and close air intake 11, avoid the oil smoke backward flow of public flue.

A filter screen 6 is arranged in the case 2 below the fan system 4, and the filter screen 6 is arranged below each muffler device and at the bottom of the case 2. That is, the filter screen 6 is disposed at the inlet of the air duct 25, and before the air duct 25 accelerates the oil smoke, the filter screen 6 and the oil smoke can be fully contacted, so as to achieve a better filtering effect. Referring to fig. 5, the filter screen 6 includes a filter screen body 61 having a reverse tapered shape with a small upper portion and a large lower portion, a mesh 62 is densely arranged on the filter screen body 61, an annular oil sump 63 is formed by extending the edge of the filter screen body 61 outward, and the outer edge of the oil sump 63 is bent upward and extends to the outside of the bottom end of the cabinet 2.

Through setting up the undercut filter screen 6 of undercut, can shorten the distance with fan system 4, be close to strong negative pressure district for when the oil smoke enters into, directly receive strong negative pressure effect, thereby improved the effect of induced drafting greatly. The air inlet on the flow field is smooth, the suction force of the range hood is not influenced, and the phenomenon of excessive oil fume leakage and suction leakage is avoided; the filter screen 6 is low in the lower periphery and high in the middle, so that the oil fume is concentrated during absorption, and the collection efficiency of the oil stains can be improved; in addition, the fume collecting depth is high, the fume is deeply absorbed without blocking, and the lower periphery of the filter screen 6 collects oil, so that the flow of the collected oil is convenient, the oil is more conveniently collected, and the dripping of oil drops is avoided.

The oil sump 63 located at the rear side of the filter screen body 61 is partially provided with a first oil drip hole 64 (located above the smoke guide plate 8), the rear end of the smoke guide plate 8 is provided with a second oil drip hole 88, the rear side lower side of the smoke collecting hood 1 is provided with an oil cup 7, the second oil drip hole 88 is located above the oil cup 5, and therefore grease collected from the cabinet 2, the fan system 4 and the filter screen 6 can be received in the oil sump 63 of the filter screen 6, and drips from the first oil drip hole 64 to the upper surface of the smoke guide plate 8, and then drips from the second oil drip hole 88 at the rear end of the smoke guide plate 8 into the oil cup 7, so as to avoid polluting cooking stovetop or cooker.

Referring to fig. 6 and 7, in the present embodiment, the fan system 4 includes two independently operable first and second three-way fan systems 41 and 42, which are disposed in parallel. By using the ternary impeller, compared with a centrifugal fan, the flow efficiency can be greatly increased, and the air quantity can be improved.

The first tertiary fan system 41 includes a first volute 411 and a first tertiary impeller 412 disposed within the first volute 411, and the second tertiary fan system 42 includes a second volute 421 and a second tertiary impeller 422 disposed within the second volute 421. The first volute 411 and the second volute 421 are arranged side by side at intervals, a first air inlet 413 is formed on the first volute 411, a second air inlet 423 is formed on the second volute 421, the air inlets of the two volutes are far away from each other, namely, the air inlet 313 of the first volute 411 is formed on one side far away from the second volute 421, the two volutes are arranged back to back, so that the two three-way fans are arranged side by side left and right, and the first air inlet 413 faces the left side of the case 2, and the second air inlet 423 faces the right side of the case 2. When the fume enters from the fume collecting hood 1, the fume enters into the fan system 4 from the left side and the right side respectively. A first oil smoke channel 441 is formed in the first volute 411, a first air outlet 414 is formed at the top end of the first oil smoke channel 441, a second oil smoke channel 442 is formed in the second volute 421, a second air outlet 424 is formed at the top end of the second oil smoke channel 442, and the first air outlet 414 and the second air outlet 424 are arranged side by side at intervals.

The first tertiary impeller 412 and the second tertiary impeller 422 may employ prior art techniques, such as those disclosed in applicant's application number 201620102790.9. The first and second three-way impellers 412 and 422 share the same driving motor 43, the driving motor 43 is disposed between the first and second volutes 411 and 421, and the driving motor 43 has a double output shaft, so that the output shaft 431 extending leftwards may be connected to the first three-way impeller 412 to drive the first three-way impeller 412 to operate, and the output shaft 431 extending rightwards may be connected to the second three-way impeller 422 to drive the second three-way impeller 422 to operate. Therefore, the two ternary fans have good synchronism, and meanwhile, energy sources can be saved.

The first and second three-way impellers 412 and 422 may respectively form 60 to 90 ° with the horizontal direction, and the two impellers are inclined in opposite directions (the first three-way impeller 412 is inclined to the left and the second three-way impeller 422 is inclined to the right), thereby reducing wind resistance and improving the oil fume absorbing effect. The center of the first ternary impeller 412 is kept at a certain distance from the inlet of the air duct 25 of the range hood, which is 1-2 times the diameter of the first ternary impeller 412, the center of the second ternary impeller 422 is kept at a certain distance from the inlet of the air duct 25 of the range hood, which is 1-2 times the diameter of the second ternary impeller 422, and the distance between the center of the impeller and the inlet of the air duct 25 must be greater than the diameter of the impeller, so that the rotary filter screen 6 at the inlet of the air duct 25 can only work, but cannot be greater than 2 times the diameter, otherwise the distance from the negative pressure area is too far.

The two ternary fans can adopt the same structure, and the overall size of the fan system is smaller in the arrangement mode, so that the original size of the case 2 is not changed, the air quantity can be doubled under the condition of keeping higher air pressure, and the oil fume suction efficiency is improved. The two air inlets face to the left and the right sides respectively, so that the area of the negative pressure areas at the periphery of the two sides is increased, the two air inlets are suitable for two cooking heads, and the effect of no smoke leakage is achieved; the noise propagation path is directed to the left and right sides, not toward the user as in the prior art, thereby reducing noise.

An air outlet cover 5 is arranged above the fan system 4, and a cover body 51 of the air outlet cover 5 covers a first air outlet 414 of a first volute 411 of the first ternary fan system 41 and a second air outlet 424 of a second volute 421 of the second ternary fan system 42 and are communicated. In this embodiment, the air outlet cover 5 includes a cover body 51 and a deflector disposed in the cover body 51. The hood 51 is hollow and cylindrical, and has opposite first and second ends 511 (lower and upper ends) and 512, the first end 511 having a larger diameter than the second end 512, i.e., the opening gradually decreases from a position closer to the fan system 4 to a position farther from the fan system 4, and the flow of soot enters the hood 51 from the first end 511 and exits the hood 51 from the second end 512 into an external duct connected to the exhaust hood 5.

The baffle includes a first baffle 521 and a second baffle 522, the first baffle 521 extending from the first end 511 to the second end 512 of the shroud 51, and the first baffle 521 corresponding at the first end 511 of the shroud 51 to a first edge 415 (right edge of the first air outlet) of the first tertiary fan system 41 proximate to the second air outlet 424 of the second tertiary fan system 42, at the first air outlet 414 of the first tertiary fan system 41, and the second baffle 522 corresponding at the first end 511 of the shroud 51 to a second edge 425 (left edge of the second air outlet) of the second tertiary fan system 42 proximate to the first air outlet 414 of the first tertiary fan system 41. Each baffle has a width extending in the front-to-rear direction. The first baffle 521 is gradually inclined toward the second baffle 522 (rightward) from the first end 511 to the second end 512, and the second baffle 522 is gradually inclined toward the first baffle 521 (leftward) from the first end 511 to the second end 512, i.e., each baffle extends from a position offset from the middle of the bottom of the casing 51 toward a position in the middle of the top of the casing 51. The top ends of the first baffle 521 and the second baffle 522 (near the second end 512 of the shroud 51) are connected to each other, and preferably, the connection between the two baffles is rounded, so as to guide the air flow to smoothly transition.

The front and rear side edges 5211, 5212 of the first baffle 521 are always connected to the inner side wall of the cover 51, and the front and rear side edges 5221, 5222 of the second baffle 522 are always connected to the inner side wall of the cover 51. The interior of the housing 51 is thus divided into a first diffusion flow passage 531 between the inner side wall of the housing 51 and the first baffle 521, and a second diffusion flow passage 532 between the inner side wall of the housing 51 and the second baffle 522, the first diffusion flow passage 531 and the second diffusion flow passage 532 being independent of each other. The first diffuser 531 corresponds to the first air outlet 414 of the first tertiary fan system 41 at the first end 511 of the shroud 51, i.e., completely covers the first air outlet 414, and the second diffuser 532 corresponds to the second air outlet 424 of the second tertiary fan system 42 at the first end 511 of the shroud 51, i.e., completely covers the second air outlet 424. The cross-sectional area of the first diffusion flow channel 531 gradually decreases from the first end 511 to the second end 512, and the cross-sectional area of the second diffusion flow channel 532 gradually decreases from the first end 511 to the second end 512, so that the outlet speed at the top of the first diffusion flow channel 531 is greater than the outlet speed at the bottom of the first diffusion flow channel 531, and the outlet speed at the top of the second diffusion flow channel 532 is greater than the outlet speed at the bottom of the second diffusion flow channel 532.

By providing the above-described baffle, the air flow speeds of the first diffuser 531 communicating with the first air outlet 414 of the first three-way fan system 41 and the second diffuser 42 communicating with the second air outlet 424 of the second three-way fan system 42 are made close to each other. The diversion effect of the air outlet cover 5 is beneficial to the formation of laminar flow of the outlet air, and the air enters the external pipeline after forming the laminar flow, so that the defect that the air flow directly enters the external pipeline in a turbulent state after exiting from the volute is avoided, and the strong friction and impact during the mixing of the air flows at the air outlets of the two three-way fans are also avoided, thereby greatly reducing the flow loss and improving the efficiency.

The sound absorbing holes 54 are densely distributed on the first baffle 521 and/or the second baffle 522, which is beneficial to reducing outlet noise. To further reduce noise, a partition 55 may be further provided in the space between the first and second baffles 521 and 522 such that the space between the first and second baffles 521 and 522 is partitioned into at least two resonant cavities 551. Alternatively, sound absorbing cotton may be provided in a space between the first baffle 521 and the second baffle 522. Alternatively, the baffle 55 may be replaced with a reinforcing rib to enhance the strength of the baffle.

Example two

Referring to fig. 8 and 9, in the present embodiment, the difference from the first embodiment described above is that the first tertiary fan system 41 and the second tertiary fan system 42 share the same volute 44, that is, the first tertiary impeller 412 of the first tertiary fan system 41 and the second tertiary impeller 422 of the second tertiary fan system 42 are disposed together in the same volute 44.

A mounting plate 45 is provided between the two three-way impellers so as to separate the two three-way impellers on both sides of the mounting plate 45, and the mounting plate 45 extends to the top end of the volute 44 so as to separate the interior of the volute 44 into two independent first oil smoke channel 441 and second oil smoke channel 442. The driving motor 43 passes through the mounting plate 45 and is fixedly connected with the mounting plate 45.

In the present embodiment, the air outlet cover 5 includes only the cover body 51 and the baffle 56 disposed in the cover body 51, the baffle 56 extends in the flow direction of the oil smoke, and in the present embodiment, the baffle 56 is located corresponding to the mounting plate 45 so as to partition the cover body 51 into the independent first diffuser 531 and the second diffuser 532 corresponding to the oil smoke passage in the volute 44.

Alternatively, the air outlet cover 5 may also adopt the structure of the first embodiment.

Claims (9)

1. The utility model provides a range hood, includes collection petticoat pipe (1), sets up quick-witted case (2) and fan system (4) of setting in quick-witted case (2) in collection petticoat pipe (1), air intake (11) have been seted up on collection petticoat pipe (1), be formed with wind channel (25), its characterized in that in machine case (2): the fan system (4) comprises a first ternary fan system (41) and a second ternary fan system (42) which are arranged in parallel, a filter screen (6) is arranged at the bottom in the case (2) and at the inlet of the air duct (25), the filter screen (6) comprises a filter screen body (61) which is in an inverted cone shape with a small upper part and a big lower part, and meshes (62) are densely distributed on the filter screen body (61);

the first ternary fan system (41) comprises a first ternary impeller (412) and a first air inlet (413), the second ternary fan system (42) comprises a second ternary impeller (422) and a second air inlet (423), on the oil smoke flow path, the second air inlet (423) is identical to the first air inlet (413) in position, and the first air inlet (413) and the second air inlet (423) are arranged in parallel and face the left side and the right side of the case (2) respectively;

the first ternary fan system (41) further comprises a first volute (411), the first ternary impeller (412) is arranged in the first volute (411), the second ternary fan system (42) further comprises a second volute (421), the second ternary impeller (422) is arranged in the second volute (421), the first volute (411) and the second volute (421) are arranged at intervals and side by side, the first air inlet (413) is formed in the first volute (411), the second air inlet (423) is formed in the second volute (421), a first oil smoke channel (441) is formed in the first volute (411), a first air outlet (414) is formed at the top end of the first oil smoke channel (441), a second oil smoke channel (442) is formed in the second volute (421), and a second air outlet (424) is formed at the top end of the second oil smoke channel (442);

an air outlet cover (5) is arranged at an air outlet of the fan system (4), the air outlet cover (5) comprises a hollow cylindrical cover body (51), the cover body (51) is provided with a first end (511) and a second end (512) which are opposite and open, the caliber of the first end (511) is larger than that of the second end (512), a first guide plate (521) and a second guide plate (522) are arranged in the cover body (51), each guide plate extends from the first end (511) of the cover body (51) to the second end (512), a first diffusion flow channel (531) is formed between the first guide plate (521) and the inner side wall of the cover body (51), a second flow channel (532) is formed between the second guide plate (522) and the inner side wall of the cover body (51), the diffusion sectional areas of the first flow channel (531) and the second diffusion flow channel (532) are gradually reduced from the first end (511) to the second end (512) of the cover body (51) respectively, the diffusion sectional areas of the first flow channel (531) and the first diffusion channel (531) are correspondingly reduced at the air outlet of the fan system (41) of the first fan system (41), the second diffusion flow passage (532) corresponds to a second air outlet (424) of the second ternary fan system (42) at a first end (511) of the cover body (51); the first guide plate (521) is gradually inclined towards the second guide plate (522) from the first end to the second end, the second guide plate (522) is gradually inclined towards the first guide plate (521) from the first end to the second end, and the top ends of the first guide plate (521) and the second guide plate (522) are mutually connected.

2. The range hood of claim 1, wherein: the edge of the filter screen body (61) outwards extends to form an annular oil collecting groove (63), and the outer edge of the oil collecting groove (63) extends to the outside of the bottom end of the chassis (2) and is bent upwards.

3. A range hood according to claim 1 or 2, wherein: the smoke guide plate (8) is arranged below the air inlet (11), and at least one part of the lower surface of the smoke guide plate (8) gradually inclines upwards from the middle to the edge, so that the smoke guide plate is matched with the corresponding wall surface of the smoke collecting hood (1) to define an accelerating flow passage with the cross section gradually reduced from bottom to top.

4. A range hood according to claim 3, wherein: the lower surface of the smoke guide plate (8) comprises at least one of a first inclined surface (81), a second inclined surface (82) and a third inclined surface (83), wherein the first inclined surface (81) is inclined upwards from the middle to the left side, a first accelerating flow channel (84) is formed between the first inclined surface and the left side plate (13) of the smoke collecting hood (1), the second inclined surface (82) is inclined upwards from the middle to the right side, a second accelerating flow channel (85) is formed between the second inclined surface and the right side plate (14) of the smoke collecting hood (1), and the third inclined surface (83) is inclined towards the front side from the middle to the third accelerating flow channel (86) is formed between the second inclined surface and the front side plate (15) of the smoke collecting hood (1).

5. The range hood of claim 4, wherein: the four corners of the upper surface of the smoke guide plate (8) are respectively provided with a connecting column (87), and the connecting columns (87) are connected to the outer edge of the air inlet (11) of the smoke collecting cover (1), so that the smoke guide plate (8) is connected with the smoke collecting cover (1).

6. The range hood of claim 5, wherein: the connecting column (87) is a telescopic rod driven by a motor.

7. The range hood of claim 1, wherein: the first ternary impeller (412) of the first ternary fan system (41) and the second ternary impeller (422) of the second ternary fan system (42) are respectively 60-90 degrees with the horizontal direction, and the two ternary impellers are inclined towards opposite directions.

8. The range hood of claim 1, wherein: the motor (43) is arranged between the first ternary impeller (412) and the second ternary impeller (422), and the motor (43) is provided with double output shafts for driving the first ternary impeller (412) and the second ternary impeller (422) respectively.

9. The range hood of claim 1, wherein: the first guide plate (521) and/or the second guide plate (522) are densely provided with sound absorption holes (54).