EP2290293A1

EP2290293A1 - A cooking fume exhauster

Info

Publication number: EP2290293A1
Application number: EP09768703A
Authority: EP
Inventors: Ruifu Zhu
Original assignee: Shandong University
Current assignee: Shandong University
Priority date: 2008-06-25
Filing date: 2009-05-13
Publication date: 2011-03-02
Also published as: EP2290293A4; JP2011525605A; US20100326419A1; WO2009155778A1

Abstract

A cooking fume exhauster is disclosed. It includes a blower (1), an oil filter (2), an enclosure of the exhauster (3), an oil fume hood (5) and lamp and multi-position keyswitches (4). A cabinet (12) of the blower (1) has a round double-chamber or multi-chamber structure which is provided with air inlet (10) and air outlet (8). An impeller (6) of the blower (1) is consisting of at least a group of single side enclosed and axially amplified arc flow channel vanes (13). The oil filter (2) is consisting of an oil-filter bracket (18), a primary oil-filter screen (17), a secondary oil-filter screen (16) and an oil collecting disk (19). The outside of the oil-filter bracket (18) is covered by the primary oil-filter screen (17). The secondary oil-filter screen (16) is mounted on the upper end of the oil-filter bracket (18) and the oil collecting disk (19) is connected with the lower end of the oil-filter bracket (18).

Description

The invention relates to an air cleaning technology field, and more particularly to a range hood.
A range hood is a cleaning tool for sucking oil smoke and harmful gases generated during cooking via an electricity-driven centrifugal fan. During daily cooking, oil smoke is inevitably generated. If it is not removed in time, after long-time use, it will cause environment pollution, white walls will turn tawny, clean vessels will be covered with oil trace, and sour and chilly smell will make a cook feel sick. Therefore, range hoods capable of removing oil smoke are almost a necessity for all families and widely used. According to statistics, annual production of the range hoods in China in 2005 is 730.1 millions.
Nowadays, there are various kinds of range hoods in development and in use. The range hoods are divided into a normal range hood, a deep shade range hood, and a deep cabinet range hood in structure, into a range hood with a single motor, into a range hood with a left motor and a right motor, and into a single-speed range hood, a double-speed range hood and a stepless speed range hood in terms of speeds. The range hood comprises a motor, a wind wheel (impeller), a cover, an oil groove, an oil trap, a light, and a switch. A basic principle is to use a fan with multiple centrifugal wind wheels for sucking oil smoke. However, the range hood with this structure has the following problems:
(1) severe oil attachment: all oil smoke discharged from the range hood passes the wind wheel with multiple blades. If the oil smoke is not purified, inner wall of the range hood will be polluted, and a large amount of oil is unevenly attached to the impeller, which causes the fan to loss dynamic balance during rotating, affects suction effect, and bring about large mechanical noise.
(2) low efficient and power consuming: range hoods widely used all over the world suck oil smoke by doing work on the oil smoke via the wind wheel. As the oil smoke is contacted with the wind wheel rotating at high speed or flows over the surface thereof, crash and friction occur not only therebetween, but also between the oil smoke and inner wall of a housing of the fan. During this period, large quantities of energy is consumed, and large noise and abrasion are generated, which causes low efficiency, large power consumption and noise, and short work life.
(3) environment pollution: the range hood functions to keep a kitchen clean, to reduce environment pollution, and to benefit people's health. However, a net absorption rate of a conventional range hood is approximately 70%. Since oil smoke often escapes and spreads, indoor air quality is poor, which is harmful for people's health, and oil trace appears everywhere on the wall. In addition, an oil screen is widely used for separating oil from smoke, but can only filter small part of the oil, which reduces cleaning rate of the oil smoke discharged to outdoors, and causes outdoor environment pollution at different degree.
(4) disassembling costs money: since severe oil attachment occurs, users have to continuously spend money on cleaning or changing the oil screen. Normally a user cleans the range hood two or three times one year, and cleaning requires professionals. Maintenance fee of the range hood is large.
To relief oil attachment, remove oil smoke, purify the air, protect environment, improve efficiency, and reduce power consumption, researchers all around the world have conducted long-term and hard research, such as improving structure of the fan, performing surface processing on the wind wheel, adding a purifier, installing a fume exhaust cover, employing a filtering net, separating oil from smoke and so on, and obtained certain effect. However, since a traditional method of using a rotating impeller for power transmission is always used, fundamental problems still exist. Although some performance is improved and increased, no breakthrough progress is made.
In view of the above-described problem, it is one objective of the invention to provide a range hood that is high efficient and power saving, has no attached oil smoke, is clean and environment-friendly, and is convenient for washing, and is capable of implementing comprehensive optimization of indoor environment, inner environment, and outdoor environment.
The invention is implemented as follows:
A range hood, comprising a fan, an oil filter, a cover, a fume exhaust cover, a light, and a switch. A housing of the fan is a circular double-chamber or multi-chamber structure with an air inlet and an air outlet, and an impeller of the fan comprises at least one group of arc-shaped blades each having a closed side and being enlarged in an axial direction.
The housing of the fan comprises a swirl chamber and an impeller chamber, the impeller is disposed in the impeller chamber and connected to a motor disposed at the top of the housing, and the air inlet is disposed at the bottom of the swirl chamber, and the air outlet is disposed on the right thereof.
A blade of the impeller is disposed on an impeller disk, the impeller disk is connected to a motor shaft of the motor, and a seal sheet is disposed in the front of the impeller disk.
The oil filter is in the shape of a frustum, and comprises a support, a primary oil screen, a secondary oil screen, and an oil tray, the primary oil screen is fit on the support, the secondary oil screen is disposed at the top of the support, the oil tray is connected to the bottom of the support, the primary oil screen and the secondary oil screen are made of soft materials, and the oil tray is made of hard materials such as plastics or metal plates.
Three sides of the fume exhaust cover are closed, a metal frame is made from a stainless plate or other metals, an upper part of the metal frame is enclosed by glass, and a lower part thereof is closed via a stainless plate or other metal plates.
The range hood of the invention comprises the fan, the oil filter, the cover, the fume exhaust cover, the light, and the switch. The invention is characterized in that the impeller comprises the blade having a closed side and being enlarged in an axial direction, and the housing of the fan is a circular double-chamber or multi-chamber structure with an air inlet and an air outlet. The fan implements a new power transmission mode - a swirling flow field mode. Oil is not attached to the range hood, which ensures cleaning of the impeller without disassembling. Compared with a conventional fan in a traditional power transmission mode, the fan of the invention features higher efficiency, lower power consumption and noise, and longer work life, oil smoke is separated from the impeller, and discharged without passing the impeller, and thus oil is not attached to the range hood. The oil filter is in the shape of a frustum, and comprises the support, the primary oil screen, the secondary oil screen, and the oil tray, the primary oil screen is fit on the support, the secondary oil screen is disposed at the top of the support, and the oil tray is connected to the bottom of the support
Advantages of the invention comprise: the impeller, the blade, and the housing cause gas not to be collided with the impeller or the housing, oil smoke does not pass the impeller, and thus volume loss, flow loss and power consumption are significantly reduced, and work life of the impeller is increased; on the other hand, the arc-shaped blades having a closed side is disposed in the double-chamber structure of the housing forms a swirling flow field that quickly rotates with respect to the shaft whereby reinforcing convergence. The swirling flow field transmits gas in a manner of driving gas via gas instead of using a rotating impeller or blade, and thus a new power transmission mode - a swirling flow field mode is formed. Oil is not attached to the range hood, which ensures cleaning of the impeller without disassembling, and the invention features high efficiency, low power consumption and noise, few consumables, easy production, and long work life.
By using the frustum-shaped oil filter, oil smoke is filtered for two times via the primary oil screen and the secondary oil screen, and thus complete separation between oil and smoke is implemented, which significantly improves purification rate of oil and smoke, ensures cleaning in the range hood, and prevents outdoor environment pollution. The primary oil screen and the secondary oil screen are made of soft materials that are convenient to be cleaned or replaced, which reduces maintenance cost.
The fume exhaust cover having three closed sides can completely cover the oil smoke and prevent it from dissipating, which improves suction efficiency, and ensures freshness of indoor air and clean of walls.
Compared with the conventional range hood, the invention increases suction efficiency by above 10% and reduces power consumption by above 10%, noise thereof is ≤50dB, suction rate of oil smoke is above 95%, purification rate of oil smoke is above 90%, and a work life thereof is three times longer than the conventional range hood. To summarize, the invention features high efficient, low power consumption and no attached oil, is clean and environment-friendly, and is convenient for washing. Technical and economic index of the invention reach the top level in the world, energy saving and emission reduction effect caused thereby is significant, and economic and social benefit is remarkable.
Principle and a technique of the invention can be widely applicable for production of range hoods in family kitchens, hotels, restaurants, cafeterias, and so on.
FIG. 1 is a schematic view of a range hood of an exemplary embodiment of the invention;
FIG. 2 is a schematic view of a fan;
FIG. 3 is a schematic view of an impeller;
FIG. 4 is a schematic view of an oil filter;
FIG. 5 is a schematic view of a fume exhaust cover in A direction; and
FIG. 6 is a schematic view of a fume exhaust cover in B direction. In which:

1 - fan; 2 - oil filter; 3 - cover; 4 - fume exhaust cover; 5 - switch; 6 - impeller; 7 - motor; 8 - air outlet; 9 - impeller chamber; 10 - air inlet; 11 - swirl chamber; 12 - housing; 13 - blade; 14 - impeller disk; 15 - seal sheet; 16 - secondary oil screen; 17 - primary oil screen; 18 - support; 19 - oil tray; 20 - metal frame; 21 - glass; 22 - stainless plate

Further description will be given below in conjunction with accompanying drawings.
As shown in FIG. 1, a range hood of the invention comprises a fan 1, an oil filter 2, a cover 3, a fume exhaust cover 4, a light, and a switch 5. As shown in FIG. 2, the fan 1 comprises a housing 12, an impeller 6, a swirl chamber 11, an impeller chamber 9, an air inlet 10, an air outlet 8, and a motor 7. The impeller 6 of the fan 1 comprises at least one group of arc-shaped blades 13 each having a closed side and being enlarged in an axial direction. The housing 12 of the fan 1 is a circular double-chamber or multi-chamber structure with the air inlet 10 and the air outlet 8. The housing 12 comprises a swirl chamber 11 and an impeller chamber 9. The impeller 6 is disposed in the impeller chamber 9 and connected to the motor 7 disposed at the top of the housing 12. The air inlet 10 is disposed at the bottom of the swirl chamber 11, and the air outlet 8 is disposed on the right of the swirl chamber 11. As shown in FIG. 3, the impeller 6 comprises the blade 13 and an impeller disk 14 connected to each other. The impeller disk 14 is connected to a motor shaft of the motor 7. A seal sheet 15 is disposed in the front of the impeller disk 14. As shown in FIG. 4, the oil filter 2 is in the shape of a frustum, and comprises a support 18, a primary oil screen 17, a secondary oil screen 16, and an oil tray 19. The primary oil screen 17 is fit on the support 18, the secondary oil screen 16 is disposed at the top of the support 18, and the oil tray 19 is connected to the bottom of the support 18. The primary oil screen 17 is made of soft materials (such as nylon screens), the secondary oil screen 16 is made of soft materials (such as multi-layer gauzes), and the oil tray 19 is made of hard materials such as plastics or metal plates. As shown in FIGS. 5 and 6, three sides of the fume exhaust cover 4 are closed, a metal frame 20 is made from a stainless plate or other metals, an upper part of the metal frame is enclosed by glass 21, and a lower part thereof is closed via a stainless plate 22 or other metal plates.

Claims

A range hood, comprising a fan (1), an oil filter (2), a cover (3), a fume exhaust cover (4), a light, and a switch (5);
characterized in that
a housing (12) of said fan (1) is a circular double-chamber or multi-chamber structure with an air inlet (10) and an air outlet (8); and
an impeller (6) of said fan (1) comprises at least one group of arc-shaped blades (13) each having a closed side and being enlarged in an axial direction.
The range hood of claim 1, characterized in that
said housing (12) of said fan (1) comprises a swirl chamber (11) and an impeller chamber (9);
said impeller (6) is disposed in said impeller chamber (9) and connected to a motor (7) disposed at the top of said housing (12); and
said air inlet (10) is disposed at the bottom of said swirl chamber (11), and said air outlet (8) is disposed on the right thereof.
The range hood of claim 1 or 2, characterized in that
a blade (13) of said impeller (6) is disposed on an impeller disk (14);

said impeller disk (14) is connected to a motor shaft of said motor (7); and
a seal sheet (15) is disposed in the front of said impeller disk (14).
The range hood of claim 1, characterized in that
said oil filter (2) is in the shape of a frustum, and comprises a support (18), a primary oil screen (17), a secondary oil screen (16), and an oil tray (19);
said primary oil screen (17) is fit on said support (18);
said secondary oil screen (16) is disposed at the top of said support (18);
said oil tray (19) is connected to the bottom of said support (18); said primary oil screen (17) and said secondary oil screen (16) are made of soft materials; and
said oil tray (19) is made of hard materials such as plastics or metal plates.
The range hood of claim 1, characterized in that
three sides of said fume exhaust cover (4) are closed;
a metal frame (20) is made from a stainless plate (22) or other metals;
an upper part of said metal frame (20) is enclosed by glass (21); and
a lower part thereof is closed via a stainless plate or other metal plates.