CN113719870A

CN113719870A - Range hood and control method thereof

Info

Publication number: CN113719870A
Application number: CN202111008696.9A
Authority: CN
Inventors: 何立博
Original assignee: Ningbo Fotile Kitchen Ware Co Ltd
Current assignee: Ningbo Fotile Kitchen Ware Co Ltd
Priority date: 2021-08-31
Filing date: 2021-08-31
Publication date: 2021-11-30

Abstract

The invention discloses a range hood and a control method thereof, the range hood comprises a smoke collecting hood, a fan frame arranged above the smoke collecting hood and a fan system arranged in the fan frame, wherein the smoke collecting hood is provided with an air inlet, and a fixed filter screen is arranged at the air inlet, and the range hood is characterized in that: the fan frame is provided with a movable screen plate below the fan system, the movable screen plate can move up and down and left and right and can transversely extend when moving, so that the gap between the movable screen plate and the fixed filter screen and the air inlet states of a left channel and a right channel below the fan system in the fan frame can be changed. Compared with the prior art, the invention has the advantages that: through setting up both can adjust the double-deck filter screen clearance, also can adjust the movable otter board of the left and right sides air inlet state, and then adjust resistance and/or oil strain ability, adapt to the multi-scene operating mode of different cooks.

Description

Range hood and control method thereof

Technical Field

The invention relates to an oil fume purification device, in particular to a range hood and a control method of the range hood.

Background

The range hood has become one of the indispensable kitchen household electrical appliances in modern families. The range hood works by utilizing the fluid dynamics principle, sucks and exhausts oil smoke through a centrifugal fan arranged in the range hood, and filters partial grease particles by using a filter screen. The centrifugal fan comprises a volute, an impeller arranged in the volute and a motor driving the impeller to rotate. When the impeller rotates, negative pressure suction is generated in the center of the fan, oil smoke below the range hood is sucked into the fan, accelerated by the fan and then collected and guided by the volute to be discharged out of a room.

The top-suction type range hood adopts an oil smoke rising principle, a negative pressure area is generated right above a cooking bench to suck and exhaust naturally rising oil smoke generated during cooking, and the range hood has the advantages of fashionable and concise appearance, larger air volume, larger space and capability of capturing the oil smoke far away from the cooking bench, and has the defects that the installation height is far away from the cooking bench, and the oil smoke above a pot is easy to be disturbed by ambient air to cause the escape of the oil smoke to the periphery under the cooking state with small oil smoke volume, so that the oil smoke suction effect is poor.

Therefore, a smoke guide plate is generally arranged below an air inlet of the top-suction range hood to form an annular suction structure, and the oil smoke suction effect is improved by utilizing the coanda effect. The top suction type range hood with the smoke guide plate disclosed in the chinese patent with the application number of 201410419676.4 comprises a body, a smoke collecting hood and the smoke guide plate, wherein the smoke collecting hood is connected with the body, a fan is arranged in the body, an air inlet is arranged on the smoke collecting hood, the smoke guide plate is arranged right opposite to the air inlet of the smoke collecting hood and fixed on the smoke collecting hood through a bracket or a buckle, and a distance exists between the smoke guide plate and the smoke collecting hood to form a smoke channel.

Because the range hood adopting the smoke guide plate does not drip oil and has better oil smoke absorption effect, the range hood has more and more extensive application in recent years. The existing range hood adopting the smoke guide plate often has the following disadvantages:

1. when the traditional range hood is used on a common double stove, the difference between the smoke quantity generated by the quick-frying side and the soup cooking side is large, and the air quantity or the area of an air inlet cannot be adjusted to adapt to the cooking condition;

2. although the air inlet of some range hoods is adjusted along with the size of oil smoke, two sets of driving motors are generally needed to realize the adjustment respectively, so that the cost is high, the stability is poor, and the popularization difficulty is high.

Disclosure of Invention

The first technical problem to be solved by the invention is to provide a range hood aiming at the defects in the prior art, which can realize the matching of the distribution of air inlet areas and resistance to cooking conditions and improve the oil smoke absorption effect.

The second technical problem to be solved by the present invention is to provide a control method of the above range hood.

The technical scheme adopted by the invention for solving the first technical problem is as follows: the utility model provides a range hood, includes collection petticoat pipe, sets up in the fan frame of collection petticoat pipe top and sets up the fan system in the fan frame, the air intake has been seted up on the collection petticoat pipe, air intake department is provided with fixed filter screen, its characterized in that: the fan frame is provided with a movable screen plate below the fan system, the movable screen plate can move up and down and left and right and can transversely extend when moving, so that the gap between the movable screen plate and the fixed filter screen and the air inlet states of a left channel and a right channel below the fan system in the fan frame can be changed.

In order to limit the up-down movement and the left-right movement of the movable screen plate, a movement mechanism for driving the movable screen plate is further arranged in the fan frame and comprises a support and a transmission rod, the support can move in the left-right direction, the transmission rod can move in the up-down direction relative to the support, and the transmission rod is further connected and fixed with the movable screen plate.

In order to facilitate the moving of the moving screen plate to be linked up and down and left and right, the moving mechanism further comprises a driving rod, a connecting rod and two first sliding blocks, wherein the driving rod is fixedly arranged in the fan frame and can rotate around an axis extending back and forth, one end of the connecting rod can slide along the left and right direction, and the other end of the connecting rod can slide along the up and down direction; the transmission rod is respectively connected with the two first sliding blocks in a rotating mode, one first sliding block is connected with the driving rod in a sliding mode and can slide along the extending direction of the driving rod, and the other first sliding block is connected with the connecting rod in a sliding mode and can slide along the extending direction of the connecting rod; the rotating shaft of the first sliding block extends in the front-rear direction.

In order to limit the movement path of the connecting rod and the bracket conveniently, the movement mechanism further comprises a second sliding block, a first sliding rail extending horizontally from left to right and a second sliding rail extending vertically are fixedly arranged in the fan frame, the first sliding rail and the second sliding rail are mutually crossed, one end of the connecting rod is connected with the first sliding rail in a sliding mode through one second sliding block, the other end of the connecting rod is connected with the second sliding rail in a sliding mode through the other second sliding block, and a rotating shaft of the second sliding block extends in the front-rear direction; the fan frame is further fixedly provided with a third slide rail which transversely extends left and right, the support is in sliding fit with the third slide rail and can move in the left and right directions, the support is provided with a fourth slide rail which extends up and down, and the transmission rod is in sliding fit with the fourth slide rail.

In order to facilitate the arrangement of the sliding rails, the moving mechanism further comprises a mounting plate fixedly arranged in the fan frame, and the first sliding rail, the second sliding rail and the third sliding rail are arranged on the mounting plate.

In order to facilitate the driving of the driving rod to rotate, the movement mechanism further comprises a driving mechanism, a support frame is fixedly arranged in the fan frame, a certain gap is formed between the support frame and the two sliding rails, the driving mechanism is arranged on the support frame, the driving mechanism is a rotation driving mechanism, and the output end of the driving mechanism penetrates through the support frame and is directly or indirectly connected with the driving rod.

Preferably, the movable screen plate is a filter screen or a plate.

The first technical solution adopted by the present invention to solve the second technical problem is: a control method of the range hood is characterized in that: the method comprises the following steps:

1) starting the range hood and operating in a default gear;

2) acquiring the current left oil smoke concentration ya and the current right oil smoke concentration yb;

3) comparing ya and yb, setting comparison reference values m1 and m2, wherein m1 represents a preset lower limit value of the difference, m2 represents a preset upper limit value of the difference, and controlling according to the comparison result:

3.1) if the difference between ya and yb exceeds m2, comparing ya and yb, and controlling accordingly according to the comparison result:

3.1.1) if ya is more than yb, controlling the movable screen plate to move to the rightmost side, fully opening the channel at the left side, and then entering the step 3.4);

3.1.2) if ya is less than yb, controlling the movable screen plate to move to the leftmost side, fully opening the right channel, and then entering the step 3.4);

3.2) if the difference between ya and yb is between m1 and m2, determining the left and right horizontal positions of the moving screen plate according to ya and yb, and then entering the step 3.4);

3.3) if the difference between ya and yb is less than m1, taking the larger value of ya and yb as yd, comparing yd with a preset oil smoke concentration threshold value y1, and performing corresponding control according to the comparison result:

3.3.1) if yd is more than y1, indicating a left and right big oil smoke scene, controlling the movable screen plate to be at the middle position in the left and right direction, and enabling the gap between the movable screen plate and the fixed filter screen to be larger, and then entering the step 4);

3.3.2) if yd is less than or equal to y1, indicating that the left and right are almost small oil smoke scenes, controlling the movable screen plate to be positioned at the middle position in the left and right direction, and controlling the gap between the movable screen plate and the fixed filter screen to be smaller, wherein the gap of the small oil smoke scene is smaller than that of the large oil smoke scene, and then entering the step 4);

3.4) taking the larger value of ya and yb as yd, comparing yd with a preset oil smoke concentration threshold value y1 or determining that the side with larger oil smoke concentration is in a small oil smoke scene, a medium oil smoke scene or a large oil smoke scene according to preset data, controlling the gaps between the movable screen plate and the fixed filter screen to be sequentially increased in the three scenes, and then entering the step 4);

4) acquiring current position information of a moving screen plate;

5) judging whether the position is matched with the current cooking scene, if so, returning to the step 2), otherwise, driving the moving screen plate to the corresponding position, and after waiting for a time interval delta ta, returning to the step 4).

Preferably, in step 3), if the judgment is accurate, the judgment is performed

Judging that the difference between ya and yb exceeds m 2; if it is not

The difference between ya and yb was judged to be between m1 andm 2; if it is not

Then ya and yb are considered to differ less than m 1.

The second technical solution adopted by the present invention to solve the second technical problem is: a control method of the range hood is characterized in that: the method comprises the following steps:

1) starting the range hood and operating in a default gear;

3.3.2) if yd is less than or equal to y1, indicating that the left and right are almost small oil smoke scenes, controlling the movable screen plate (which is positioned at the middle position in the left and right direction and has a small gap with the fixed filter screen, wherein the gap of the small oil smoke scene is smaller than that of the large oil smoke scene, and then entering the step 4);

4) acquiring current position information of a moving screen plate;

5) judging whether the position is matched with the current cooking scene, if so, entering the step 6), otherwise, driving the movable screen plate (4) to the corresponding position, and returning to the step 4 after waiting for a time interval delta Ta;

6) acquiring the current flow Qm flowing through the fan system;

7) judging whether Qm is in [ Qx, Qd ] of the corresponding cooking scene, wherein Qx and Qd are respectively the upper and lower limit values of the corresponding cooking scene, if yes, entering step 8), and if not, entering step 9);

8) continuing monitoring, wherein the monitoring frequency s is s +1, judging whether s is greater than or equal to s1, s1 is a preset threshold value for the monitoring frequency, if so, writing the gear and the position of the current scene into a storage updating preset value, resetting s to be 0, and then returning to the step 2); if not, continuing to monitor, and returning to the step 2);

9) if Qm > Qd, go to step 11), if Qm < Qx, go back to step 6);

10) judging whether the gear or the rotating speed of a fan system of the current range hood is the lowest or not, and if so, entering the step 11); if not, the 1 st gear is adjusted down, and the step 6) is returned;

11) judging whether the gap of an air inlet channel between the current movable screen plate and the fixed filter screen is minimum or not, and if so, prompting maintenance; if not, the movable screen plate is lowered, the air inlet channel is reduced, and the step 6 is returned to);

12) judging whether the gear or the rotating speed of a fan system of the current range hood is highest, if so, entering the step 13); if not, the 1 st gear is increased, and the step 6) is returned;

13) and (4) judging whether the air inlet channel gap between the current movable screen plate and the fixed filter screen is the maximum, if so, prompting to clean, otherwise, heightening the movable screen plate, enlarging the air inlet channel, and returning to the step 6).

Preferably, in step 3), if the judgment is accurate, the judgment is performed

Judging that the difference between ya and yb exceeds m 2; if it is not

The difference between ya and yb is judged to be between m1 and m 2; if it is not

Then ya and yb are considered to differ less than m 1.

The third technical solution adopted by the present invention to solve the second technical problem is: a control method of the range hood is characterized in that: the method comprises the following steps:

1) standby of the range hood;

2) recording a group of left and right temperature information, and acquiring a left temperature value and a right temperature value;

3) judging whether 2 groups of temperature values at different time exist, and if so, entering the step 4); if not, returning to the step 2) after waiting for the time interval delta t;

4) calculating the left temperature change slope kL ═ TL2-TL1)/Δ t, and calculating the right temperature change slope kR ═ TR2-TR1)/Δ t; TL2 and TL1 are two sets of left side temperature values, where TL2 times later, and TR2 and TR1 are two sets of right side temperature values, where TR2 times later;

5) reading the stored left temperature change slope reference value kLa and the right temperature change slope reference value kRa;

6) respectively comparing kL with kLa, kR and kRa, if the kL is greater than kLa and the kL is positive, starting the range hood to suck the oil smoke, and entering the step 8); if | kL | is more than kLa and kL is negative, or | kL | is less than or equal to kLa, then entering step 7); if the absolute value of kR is more than kRa and kR is positive, starting the range hood to suck the oil smoke and entering the step 8); if | kR | is > kRa and kR is negative, or | kR | ≦ kRa, then proceed to step 7);

7) judging whether TR2 is smaller than a preset right-side temperature reference value Tra and TL2 is smaller than a preset left-side temperature reference value TLa, if so, not starting the range hood, if not, starting the range hood to suck oil smoke, and entering step 8);

8) comparing kL and kR, if kL-kR is larger than k theta, indicating a cooking scene mainly comprising left-side oil smoke absorption, and entering the step 9); if the | kL-kR | is less than k theta, the same cooking scenes on the left side and the right side are represented, and the step 9) is carried out; if kR-kL is more than k theta, the cooking scene mainly including oil smoke absorption at the right side is represented, and the step 9) is carried out; k theta is a threshold value of a preset temperature change slope difference value;

9) judging whether the temperature value changes suddenly, if so, adjusting to the position of the large oil smoke to operate under the corresponding cooking scene, defaulting the large gear of the fan system (3), and entering the step 10); if not, adjusting to the small oil smoke position to operate in the corresponding cooking scene, and enabling the fan system (3) to default to a small gear, and entering the step 10);

10) acquiring current position information of the moving screen plate;

11) judging whether the current position of the movable screen plate is matched with the current cooking scene, if so, entering the step 12), otherwise, driving the movable screen plate to the corresponding position, and returning to the step 10 after waiting for a time interval delta ta;

12) acquiring the flow Qm of the current fan system;

13) judging whether Qm is in [ Qx, Qd ] of the corresponding cooking scene, wherein Qx and Qd are respectively the upper and lower limit values of the corresponding cooking scene, if yes, entering step 14), and if not, entering step 15);

14) continuing monitoring, wherein the monitoring frequency s is s +1, judging whether s is greater than or equal to s1, s1 is a preset threshold value for the monitoring frequency, if so, writing the gear and the position of the current cooking scene into a storage updating preset value, and resetting s to be 0; if not, continuing to monitor, and returning to the step 2);

15) if Qm > Qd, go to step 16), if Qm < Qx, go to step 18);

16) judging whether the gear or the rotating speed of a fan system of the current range hood is the lowest or not, and if so, entering the step 17); if not, the 1 st gear is adjusted down, and the step 12) is returned;

17) judging whether the gap between the current moving screen plate and the fixed filter screen is minimum or not, and if so, prompting maintenance; if not, the movable screen plate is lowered, the gap is reduced, and the step 12) is returned;

18) judging whether the gear or the rotating speed of a fan system of the current range hood is highest, if so, entering a step 19); if not, the 1 st gear is increased, and the step 12) is returned;

19) and (4) judging whether the gap between the current movable screen plate and the fixed filter screen is the maximum, if so, prompting to clean, otherwise, heightening the movable screen plate, enlarging the gap, and returning to the step 12).

Preferably, in step 9), when the cooking device is in a single-side cooking scene mainly taking oil smoke absorption on the left side or the right side, the movable screen plate is positioned on the corresponding small oil smoke side, and the gap between the movable screen plate and the fixed filter screen at the large oil smoke position is larger than the gap between the movable screen plate and the fixed filter screen at the small oil smoke position; when the absolute value kL-kR is less than k theta, the movable screen plate is positioned in the middle of the fan frame in the left-right direction.

The fourth technical solution adopted by the present invention to solve the second technical problem is: a control method of the range hood is characterized in that: the method comprises the following steps:

1) starting the range hood, and operating the range hood in a default gear or in a balanced manner on the left side and the right side;

2) acquiring the current oil smoke amount of the left side and the right side;

3) judging whether the difference of the oil smoke amount of the left side and the oil smoke amount of the right side is larger than a preset threshold value, if so, entering the step 4), and if not, entering the step 6);

4) driving the movable screen plate to move to one side of the small oil smoke, and determining a gap between the movable screen plate and the fixed filter screen according to the oil smoke amount on the left side and the right side;

5) waiting for the time interval delta t, reading the position of the movable screen plate again, judging whether the position of the movable screen plate accords with the cooking state, if so, returning to the step 2), and if not, repeating the step;

6) reading the position of the current moving screen plate;

7) judging whether the position of the current moving screen plate accords with the cooking state, if so, returning to the step 2), and if not, driving the moving screen plate (4) to move to the corresponding position;

8) waiting for the time interval delta t, reading the position of the movable screen plate again, judging and judging whether the position of the movable screen plate accords with the cooking state, if so, returning to the step 2), and if not, repeating the step.

Compared with the prior art, the invention has the advantages that: by arranging the movable screen plate, the gap between the double-layer filter screens can be adjusted, and the air inlet states of the left side and the right side can also be adjusted, so that the resistance and/or the oil filtering capability are adjusted, and the multi-scene working conditions of different cooking are adapted; through the cooperation of the driving rod, the connecting rod and the sliding rail, the movable screen plate can move up, down, left and right through one set of mechanism, and the mechanism is simple and stable.

Drawings

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

fig. 2 is a sectional view of the range hood according to the embodiment of the present invention in a first state;

FIG. 3 is a schematic view of a moving screen plate of the range hood of FIG. 2;

FIG. 4 is an exploded schematic view of the movement mechanism of the range hood motorized mesh panel of FIG. 3;

fig. 5 is a sectional view of the range hood in the second state according to the embodiment of the present invention;

FIG. 6 is a schematic view of a moving mechanism of a moving screen plate of the range hood of FIG. 5;

fig. 7 is a sectional view of the range hood according to the embodiment of the present invention in a third state;

FIG. 8 is a schematic view of a moving mechanism of a moving screen plate of the range hood of FIG. 7;

fig. 9 is a sectional view of the range hood according to the embodiment of the present invention in a fourth state;

FIG. 10 is a schematic view of a moving mechanism of a moving screen plate of the range hood of FIG. 9;

fig. 11 is a sectional view of the range hood according to the embodiment of the present invention in a fifth state;

FIG. 12 is a schematic view of a moving mechanism of a moving screen plate of the range hood of FIG. 11;

fig. 13 is a sectional view of a range hood according to an embodiment of the present invention in a sixth state;

FIG. 14 is a schematic view of a moving mechanism of a moving screen plate of the range hood of FIG. 13;

fig. 15 is a sectional view of the range hood according to the embodiment of the present invention in a seventh state;

FIG. 16 is a schematic view of a moving mechanism of a moving screen plate of the range hood of FIG. 15;

fig. 17 is a flowchart of a first control method of the range hood according to the embodiment of the present invention;

fig. 18 is a flowchart of a second control method of the range hood according to the embodiment of the present invention;

fig. 19 is a flowchart of a third control method of the range hood according to the embodiment of the present invention;

fig. 20 is a flowchart of a fourth control method of the range hood according to the embodiment of the present invention.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar functions.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the present invention and to simplify the description, but are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and that the directional terms are used for purposes of illustration and are not to be construed as limiting, for example, because the disclosed embodiments of the present invention may be oriented in different directions, "lower" is not necessarily limited to a direction opposite to or coincident with the direction of gravity. Furthermore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

Referring to fig. 1 to 4, a range hood is a ceiling range hood, and includes a fume collecting hood 1 and a fan frame 2 disposed above the fume collecting hood 1, and a fan system 3 is disposed in the fan frame 2. The smoke collecting cover 1 is provided with an air inlet 11, so that the oil smoke can enter the fan frame 2 from the air inlet 11 in the upward rising process and is discharged by the fan system 3. The bottom of the fume collecting hood 1 is upwards sunken to form a fume collecting cavity 12, and the air inlet 11 is positioned at the top of the fume collecting cavity 12.

The space in the fan frame 2 below the fan system 3 is divided into a left channel and a right channel. The fan frame 2 is located below the fan system 3, that is, on the oil smoke flow path, the moving screen plate 4 is located at the upstream of the fan system 3, and the moving screen plate 4 is preferably in a flat plate shape and can move inside the fan frame 2. The air inlet 11 is provided with a fixed filter screen 5, and the fixed filter screen 5 can be a cone which is gradually reduced from top to bottom and is fixed at the air inlet 11. The smoke guide plate 6 is arranged below the fixed filter screen 5, and as in the prior art, oil smoke enters the fan frame 2 through the air inlet 11 from a channel between the periphery of the smoke guide plate assembly and the smoke collection cover 1.

The movable net plate 4 is rectangular, and as shown in fig. 2, the left-right direction is the length direction of the movable net plate 4. The movable screen plate 4 is provided with meshes 41 to form a grid net, and the oil filtering capacity and resistance can be adjusted at the moment. Alternatively, the moving mesh plate 4 is a plate without holes, and only the resistance is adjusted to distribute the flow. That is, in the present invention, the movable mesh plate 4 refers to a screen or a plate.

The inside of the fan frame 2 is also provided with a movement mechanism for driving the moving screen plate 4 to move, and the movement mechanism comprises a mounting plate 71, a driving rod 72, a connecting rod 73, a first slide block 74, a second slide block 75 and a driving mechanism 76. The mounting plate 71 is fixedly disposed on the inner side of the fan frame 2, and may be directly connected and fixed to the inner side of the fan frame 2, or may be connected and fixed to the inner side of the fan frame 2 by a mounting plate or the like. In the present embodiment, the mounting plate 71 is disposed at the rear side in the fan frame 2, and the above-described movable mesh plate 4 is disposed at the front side of the mounting plate 71.

The mounting plate 71 is provided with a first slide rail 711 extending in the left-right lateral direction and a second slide rail 712 extending in the up-down direction, and the first slide rail 711 and the second slide rail 712 intersect with each other. The mounting plate 71 is further provided with a support bracket 713, and the support bracket 713 is located at the front side of the two slide rails and has a certain gap with the two slide rails. The driving mechanism 76 is disposed on the supporting frame 713 and located at the front side of the supporting frame 713, the driving lever 72 is disposed between the supporting frame 713 and the two slide rails, and the driving mechanism 76 is a rotation driving mechanism, such as a motor, and preferably, can drive the driving lever 72 to rotate around an axis extending back and forth. The output of the drive mechanism 76 may pass through the support 713 and thereby be connected directly or indirectly to the active lever 72.

The mounting plate 71 is further provided with a third slide rail 714 extending laterally from left to right, the movement mechanism further comprises a bracket 77 and a transmission rod 78, the bracket 77 is in sliding fit with the third slide rail 714 and can move in the left-right direction, the bracket 77 is provided with a fourth slide rail 771 extending vertically, and the transmission rod 78 is in sliding fit with the fourth slide rail 771 and can move in the vertical direction along the fourth slide rail 771. The first sliders 74 are provided with two transmission rods 78, the transmission rods 78 are connected with the driving rod 72 and the connecting rod 73 in a sliding mode, the transmission rods 78 are connected with the first sliders 74 in a rotating mode, one of the first sliders 74 is connected with the driving rod 72 in a sliding mode (slider groove matching or guide rail matching) and can slide along the extending direction of the driving rod 72, and the other first slider 74 is connected with the connecting rod 73 in a sliding mode (slider groove matching or guide rail matching) and can slide along the extending direction of the connecting rod 73. The transmission rod 78 is also connected and fixed with the movable net plate 4. Preferably, the first slider 74 is disposed at the upper end of the transmission rod 78, and the moving mesh plate 4 is disposed at the lower end of the transmission rod 78. The number of the second sliders 75 is also two, one end of the connecting rod 73 is slidably connected to the first slide rail 711 through one of the second sliders 75, and the other end of the connecting rod 73 is slidably connected to the second slide rail 712 through the other second slider 75. The link 73 is rotatably connected to the second slider 75. The rotating shafts of the rod pieces and the sliding blocks extend in the front-back direction.

When the driving mechanism 76 is activated, the driving rod 72 can be driven to rotate, so that the first slider 74 slides relative to the driving rod 72, the movement of the two ends of the connecting rod 73 and the up-down movement of the transmission rod 78 are restrained, the bracket 77 is further driven to move left and right, and finally the movable screen plate 4 can move up and down and follow up left and right under the restraint of each sliding rail. The movable net plate 4 is kept in a transversely extending state, such as a horizontal state or a nearly horizontal state, in the moving process.

In this embodiment, the up-down movement and the left-right movement of the moving screen plate 4 are realized by one driving mechanism 76 in combination with a rod member, a slide rail, and the like, alternatively, the moving screen plate 4 may also be independently driven by two sets of driving mechanisms 76 to move up-down and left-right, and at this time, the driving mechanisms 76 are correspondingly selected from a linear driving mechanism or a rotational driving mechanism for adaptation.

In the practical use process, the condition of frying on one side of the kitchen range under the range hood is more, but the other side is not used or has no smoke, and the cooking state can be switched between big smoke and small smoke. The oil filtering capacity and the resistance are a pair of related contradictions, and the two are difficult to be considered on the common range hood, but in the invention, one or two of a left channel and a right channel in the fan frame 2 can be adjusted to be an air inlet main channel by the left and right movement of the movable screen plate 4 according to the oil smoke condition of a working condition through the movement of the movable screen plate 4, so that the channel with a larger area is positioned on the side of large oil smoke, the gap between the movable screen plate 4 and the fixed filter screen 5 can be adjusted according to the smoke volume or the system resistance, the system resistance is further changed, the large oil smoke preferentially ensures the oil smoke absorption, and the small oil smoke preferentially ensures the oil filtering.

In the invention, the large oil fume and the small oil fume refer to the actual working state flow of the range hood installed at the home of a user, the flow can be defined according to the laboratory test condition, and the preferable dividing line of the flow can be 6-10 m³And/min. According to the difference between different on-hook heights and machine types, for example, the ceiling type range hood is installed according to the standard (the installation range is 650-750mm defined by the national standard), the flow limit of 700mm from the platform surface may be 9m³And when the mounting height thereof is adjusted to 750mm, the boundary thereof needs to be lifted up to 10m³The oil smoke escape is reduced.

Referring to fig. 2, the first operating state of the range hood of the present invention is suitable for a cooking scenario where the difference between the left side and the right side is slightly large, and the left side is mainly used for absorbing oil smoke, and the whole oil smoke is slightly small, at this time, the movable screen 4 is close to the right side (one end of the connecting rod 73 is located at the position close to the right of the first sliding rail 711, and the other end is located at the position close to the lower part of the second sliding rail 712), so that the right side resistance is increased, the main flow is on the left side, the gap between the movable screen 4 and the fixed filter screen 5 is small, oil filtering is performed preferentially, and the filtering efficiency is improved.

Referring to fig. 5 and 6, in a second operating state of the range hood of the present invention, suitable for a cooking situation where the difference between the left and right sides is slightly large, the left side absorbs oil smoke mainly, and the whole oil smoke is moderately large, on the basis of fig. 2, the driving mechanism 76 drives the driving rod 72 to rotate clockwise, so that one end of the connecting rod 73 moves upward along the second sliding rail 712 to a position above the first sliding rail 711, and the other end moves rightmost along the first sliding rail 711, and at the same time, drives the driving rod 78 to move upward, and drives the movable screen plate 4 to move upward, so that the gap between the movable screen plate 4 and the fixed filter screen 5 is large, the oil smoke is absorbed preferentially, and the air intake efficiency is improved.

Referring to fig. 7 and 8, in a third operating state of the range hood of the present invention, which is suitable for a cooking scenario where the difference between the left side and the right side is large, the left side has a main oil smoke absorption, and the whole oil smoke is small, on the basis of fig. 2, the driving mechanism 76 drives the driving rod 72 to rotate counterclockwise, such that one end of the connecting rod 73 moves upward along the second sliding rail 712, the other end moves rightward to the rightmost side along the first sliding rail 711, and simultaneously drives the driving rod 78 to move upward, the movable screen plate 4 is driven to move upward and rightward, the two layers (screen plates) of the movable screen plate 4 and the fixed screen plate 5 increase the right side resistance, such that the main flow is on the left side, the gap between the movable screen plate 4 and the fixed screen plate 5 is small, the oil smoke absorption is guaranteed, and the oil filtration is prioritized. Vice versa, see fig. 15 and 16.

Referring to fig. 9 and 10, in a fourth operating state of the range hood of the present invention, which is suitable for a cooking scenario where the difference between the left side and the right side is large, oil smoke is mainly absorbed on the left side, and the oil smoke is moderately large in the whole oil smoke, on the basis of fig. 7, the driving mechanism 76 continues to drive the driving rod 72 to rotate counterclockwise, so that one end of the connecting rod 73 moves upward above the first sliding rail 711 along the second sliding rail 712, and the other end moves rightmost along the first sliding rail 711, and at the same time, the driving rod 78 moves upward and rightward, the movable screen plate 4 is driven upward and rightward, and the two layers (screen plates) of the movable screen plate 4 and the fixed screen plate 5 increase the right-side resistance, so that the main flow is on the left side, the gap between the movable screen plate 4 and the fixed screen plate 5 is large, and the oil smoke absorption is preferred.

Referring to fig. 11 and 12, in order to provide a fifth working state of the range hood of the present invention, which is suitable for a cooking scenario where the difference between the left side and the right side is small, the oil smoke on the two sides is not much, and the whole oil smoke is small, on the basis of fig. 2, the driving mechanism 76 drives the driving rod 72 to rotate counterclockwise, so that one end of the connecting rod 73 moves upward along the second sliding rail 712 not to exceed the first sliding rail 711, and the other end moves rightmost along the first sliding rail 711, and at the same time, the driving rod 78 moves upward and leftward, the moving screen plate 4 is driven to move upward and leftward and is located at the middle position in the left-right direction, the left-side flow and the right-side flow are similar, the gap between the moving screen plate 4 and the fixed filter screen 5 is small, the oil smoke absorption is guaranteed, and the oil filtration is prioritized.

Referring to fig. 13 and 14, in a sixth operating state of the range hood of the present invention, which is suitable for a cooking scenario where the difference between the left side and the right side is small, the oil smoke on the two sides is almost the same, and the overall oil smoke is medium and large, on the basis of fig. 11, the driving mechanism 76 continues to drive the driving rod 72 to rotate counterclockwise, so that one end of the connecting rod 73 moves upward to the position of the first sliding rail 711 along the second sliding rail 712, and at the same time, the driving rod 78 is driven to move upward, the movable screen plate 4 is driven to move upward, the gap between the movable screen plate 4 and the fixed filter screen 5 is large, and oil smoke absorption is preferred.

The range hood of the invention has the following control methods. In the first control method, a position sensor can be arranged on the movable screen plate 4 and used in combination with a left oil smoke sensor and a right oil smoke sensor, and both the two oil smoke sensors can be respectively arranged at the bottoms of the left side and the right side of the smoke collecting hood 1; the range hood has no power or current detection feedback. Referring to fig. 17, the method specifically includes the following steps:

1) starting the range hood and operating in a default gear;

2) reading information of the oil smoke sensors, including information of a left oil smoke sensor a and information of a right oil smoke sensor b, and obtaining the current left oil smoke concentration and the current right oil smoke concentration; and reading the stored soot concentration threshold y 1;

3) comparing whether the oil smoke concentrations detected by the current oil smoke sensors are obviously different or not, and performing corresponding control according to the comparison result, wherein ya represents the oil smoke concentration value on the left side, yb represents the oil smoke concentration value on the right side, and the reference values are m1 and m2, wherein m1 represents a preset lower difference value limit value, and m2 represents a preset upper difference value limit value:

3.1) if

Indicating a significant large difference in oil concentration on both sides, then ya and yb are compared and controlled accordingly according to the comparison:

3.1.1) if ya is more than yb, controlling the movable screen plate 4 to move to the rightmost side, fully opening the channel at the left side, and then entering the step 3.4);

3.1.2) if ya is less than yb, controlling the movable screen plate 4 to move to the leftmost side, fully opening the right channel, and then entering the step 3.4);

3.2) if

The oil smoke concentration on the two sides is considered to be slightly different, and the oil smoke on the left side and the right side is larger and smaller on one side, according to the difference

And

determining the left and right horizontal positions of the moving screen plate 4 by using a table look-up of the sizes and relative proportions, and then entering step 3.4);

3.3) if

And if the oil smoke concentrations at the two sides are not different, taking the larger value of ya and yb as yd, comparing the yd with a preset oil smoke concentration threshold value y1, and performing corresponding control according to the comparison result:

3.3.1) if yd is more than y1, indicating a left and right oil smoke scene, controlling the movable screen plate 4 to be at the middle position in the left and right direction, and enabling the gap between the movable screen plate and the fixed filter screen 5 to be larger, and then entering the step 4);

3.3.2) if yd is less than or equal to y1, indicating that the left and right are almost small oil smoke scenes, controlling the movable screen plate 4 to be positioned at the middle position in the left and right direction, and controlling the gap between the movable screen plate and the fixed filter screen 5 to be smaller, wherein the gap of the small oil smoke scenes is smaller than that of the large oil smoke scenes, and then entering the step 4);

3.4) taking the larger value of ya and yb as yd, comparing the yd with a preset oil smoke concentration threshold value y1 or checking a table stored in the yd to determine that the side with the larger oil smoke concentration is in a small oil smoke scene, a medium oil smoke scene or a large oil smoke scene, controlling the gaps between the movable screen plate 4 and the fixed filter screen 5 to be sequentially increased in the three scenes, and then entering the step 4); in this step, when comparing yd and y1, if the magnitude relationship between the multiples of yd and y1 can be set, the three oil smoke scenes can be divided;

4) acquiring current position information of the moving screen plate 4 through a position sensor and an angle sensor on the moving screen plate 4;

5) judging whether the position is matched with the current cooking scene, if so, returning to the step 2), otherwise, driving the movable screen plate 4 to the corresponding position by the driving mechanism 76, and after waiting for the time interval delta ta, returning to the step 4).

In the above control flow, use is made of

As a reference value for comparison, it is considered that the dynamic change of the soot concentration value of the soot sensor is large, and it needs to be converted into a certain characteristic range, so that it is convenient to set a preset value when leaving a factory, and then the preset value is compared with the preset value. Thus, it is considered to convert it into [0, 1 ]]Within the range of (3), it is convenient to set the thresholds of m1, m2, and the like. Meanwhile, the denominator adopts a value obtained by subtracting the oil smoke concentration values detected by the two sensors, and the relative difference (large difference, small difference and larger difference) can be reflected by the size of the denominator; but when two different environments or different cooking stagesWhen the values are compared, it may be that the two stage values cannot be compared directly by using the subtracted values of the front and rear two groups, such as the oil smoke concentration values of ya, yb, ya 'and yb', which differ by tens of times, even hundreds of times, because of the problem of large dynamic change of the oil smoke concentration value.

Therefore, in the present embodiment, it is considered to adopt

Namely, the comparison range can be converted into 0, 1]In addition, the left and right cooking differences can be presented, and the left and right cooking differences under different times, different user environments and different fuming cooking conditions can be conveniently compared.

For example:

the unit of ya is 100, yb is 700 at time A, and may be mg/m³Or other uniform units;

the unit of ya is 1000, yb is 5000, and the unit can be mg/m at the time B³Or other uniform unit.

If the difference between the two moments before and after the direct comparison is carried out, the difference is about 1 order of magnitude between 600VS 4000, and the comparison cannot be carried out. By adopting the comparison method of the invention, the difference |100 |/|100+700| -0.75 at the time A, and the difference |1000 |/| -5000| -0.66 at the time B can be found to be convenient for comparison, and obviously, the difference between the left and the right at the time A is larger.

The second control method is different from the range hood structure used by the first control method in that the range hood has power or current detection feedback and can adjust air volume or gears. Referring to fig. 18, the method specifically includes the following steps:

1) starting the range hood and operating in a default gear;

2) reading information of the oil smoke sensors, including information of a left oil smoke sensor a and information of a right oil smoke sensor b, and obtaining the current left oil smoke concentration and the current right oil smoke concentration;

3.1) if

3.2) if

And

3.3) if

5) judging whether the current position of the movable screen plate 4 is matched with the current cooking scene, if so, entering the step 6), if not, driving the movable screen plate 4 to a corresponding state by the driving mechanism 76, and returning to the step 4 after waiting for a time interval delta Ta).

6) Acquiring current power or rotation speed and a power or rotation speed coefficient of a current position, and calculating to obtain the current flow Qm flowing through the fan system 3;

7) judging whether Qm is in [ Qx, Qd ] of the corresponding scene, wherein Qx and Qd are respectively the upper and lower limit values of the corresponding scene, if yes, entering step 8), and if not, entering step 9);

9) judging whether Qm is larger or smaller, if larger, namely Qm is larger than Qd, entering step 10), and if smaller, namely Qm is smaller than Qx, entering step 12);

10) judging whether the gear or the rotating speed of the fan system 3 of the current range hood is the lowest or not, and if so, entering the step 11); if not, the 1 st gear is adjusted down, and the step 6) is returned;

11) judging whether the gap (air inlet channel) between the current movable screen plate 4 and the fixed filter screen 5 is minimum or not, and if so, prompting maintenance; if not, the movable screen plate 4 is lowered, the air inlet channel is reduced, and the step 6 is returned to);

13) and (3) judging whether the gap (air inlet channel) between the movable screen plate 4 and the fixed filter screen 5 is the maximum or not, if so, prompting to clean, otherwise, heightening the movable screen plate 4, enlarging the air inlet channel, and returning to the step 6).

The third control method is different from the range hood structure utilized by the first control method in that the movable screen plate 4 is not provided with a position sensor, the rotating step is detected only by the driving mechanism 76, or the rotating angle is calculated based on the rotating speed and the time product to judge the position of the movable screen plate 4, the range hood is provided with a temperature sensor for use, the range hood can automatically switch the range hood state on and off, and whether the current mode is met or not is confirmed according to the feedback of the air volume calculation, so that the state is adjusted. Referring to fig. 19, the method specifically includes the following steps:

1) the range hood is in standby state, and the temperature sensor monitors operation;

2) recording a group of left and right temperature information, and acquiring the numerical value of a left temperature sensor L and the numerical value of a right temperature sensor R;

3) judging whether 2 groups of temperature values with different time exist, if so, entering the step 4); if not, returning to the step 2) after waiting for the time interval delta t;

4) calculating the left temperature change slope kL ═ TL2-TL1)/Δ t, and calculating the right temperature change slope kR ═ TR2-TR1)/Δ t; TL2 and TL1 are values of two groups of left side temperature sensors, wherein TL2 is time later, and TR2 and TR1 are values of two groups of right side temperature sensors, wherein TR2 is time later;

5) reading the stored left and right temperature change slope reference values kLa and kRa;

6) respectively comparing kL with kLa, kR and kRa, if the kL is greater than kLa and the kL is positive, starting the range hood to smoke, and entering the step 8); if | kL | is more than kLa and kL is negative, or | kL | is less than or equal to kLa, then entering step 7); if the absolute value of kR is more than kRa and kR is positive, starting the range hood to smoke and entering the step 8); if | kR | is > kRa and kR is negative, or | kR | ≦ kRa, then proceed to step 7);

7) judging whether TR2 is smaller than a preset right-side temperature reference value Tra and TL2 is smaller than a preset left-side temperature reference value TLa, if so, not starting the range hood, if not, starting the range hood to smoke, and entering step 8);

8) comparing kL and kR, if kL-kR is more than ktheta, indicating that smoking on the left side is dominant, and entering the step 9); if the | kL-kR | is less than k theta, the left side and the right side are similar, and the step 9) is carried out; if kR-kL is more than ktheta, indicating that smoking on the right side is dominant, and entering step 9); k theta is a threshold value of a preset temperature change slope difference value;

9) judging whether the temperature value changes suddenly, if so, adjusting the position of the large oil smoke in each state to operate, namely controlling the movable screen plate 4 to be positioned in the right channel and have a larger gap with the fixed filter screen 5 when the large oil smoke on the left side exists, and controlling the fan system 3 to default to a large gear when the large oil smoke on the right side exists, and entering the step 10); if not, adjusting the small oil smoke position to each state to operate, namely when the left side small oil smoke exists, controlling the movable screen plate 4 to be positioned in the right side channel and the gap between the movable screen plate and the fixed filter screen 5 to be smaller, and when the right side small oil smoke exists, controlling the fan system 3 to default to a small gear, and entering the step 10); when the absolute value kL-kR is less than k theta, the movable screen plate 4 is positioned in the middle of the left and right directions of the fan frame 2;

10) acquiring current position information through the motor rotation step or angle of the driving mechanism 76 corresponding to the movable screen plate 4;

11) judging whether the position is matched with the current cooking scene, if so, entering the step 12), if not, driving the moving screen plate 4 to the corresponding position by the driving mechanism 76, and returning to the step 10 after waiting for the time interval delta ta).

12) Acquiring current power or rotation speed and the power or rotation speed coefficient of the current position, and calculating to obtain the current flow Qm of the fan system 3 flowing through the range hood;

13) judging whether Qm is in [ Qx, Qd ] of the corresponding scene, wherein Qx and Qd are respectively the upper and lower limit values of the corresponding scene, if yes, entering step 14), and if not, entering step 15);

14) continuing monitoring, wherein the monitoring frequency s is s +1, judging whether s is greater than or equal to s1, s1 is a preset threshold value for the monitoring frequency, and if so, writing the gear and the position of the current scene into a storage updating preset value and resetting s to be 0; if not, continuing to monitor, and returning to the step 2);

15) judging whether Qm is larger or smaller, if larger, namely Qm is larger than Qd, entering step 16), and if smaller, namely, Qm is smaller than Qx, entering step 18);

16) judging whether the gear or the rotating speed of the fan system 3 of the current range hood is the lowest or not, and if so, entering the step 17); if not, the 1 st gear is adjusted down, and the step 12) is returned;

17) judging whether the gap between the current moving screen plate 4 and the fixed filter screen 5 is minimum or not, and if so, prompting maintenance; if not, the movable screen plate 4 is lowered, the air inlet channel is reduced, and the step 12 is returned to);

18) judging whether the gear or the rotating speed of the fan system 3 of the current range hood is highest, if so, entering a step 19); if not, the 1 st gear is increased, and the step 12) is returned;

19) and (4) judging whether the gap between the movable screen plate 4 and the fixed filter screen 5 is the maximum or not, if so, prompting to clean, otherwise, heightening the movable screen plate 4, enlarging the air inlet channel, and returning to the step 12).

In the fourth control method, the driving mechanism detects the rotating steps, or the rotating angle is calculated based on the product of the rotating speed and the time, so that the user can select a mode or other sensor feedback values. Referring to fig. 20, the method specifically includes the following steps:

2) the cooking state is obtained by user input or smoke stove electric feedback or smoke and infrared sensors, and all the cooking states can be summarized as the amount of oil smoke;

3) judging whether the difference between the left side and the right side is larger than a preset threshold value, if so, indicating that obvious difference exists, and if not, indicating that the two sides are almost cooking scenes, for example, comparing the oil smoke quantity or the temperature, wherein the judgment mode can be the first control method, the second control method and the third control method, or the judgment method commonly used in the field can be adopted; if yes, entering step 4), if no, entering step 6);

4) the driving mechanism 76 is started, the movable screen plate 4 rotates to one side of small oil smoke, and the gap between the movable screen plate and the fixed filter screen 5 is determined by looking up a table according to the ratio between the oil smoke concentration value at one side of large oil smoke and the threshold value; the relation between the oil smoke concentration and the gap can be obtained in advance through experiments or empirical values and stored in a control module of the range hood;

5) waiting for the time interval delta t, reading the position of the driving mechanism 76 or the movable screen plate 4 again, judging whether the moving mechanism adjusts the movable screen plate 4 to be in place, if so, returning to the step 2), and if not, repeating the step;

6) reading the position of the current moving screen plate 4 according to the step or angle of the motor of the driving mechanism 76;

7) judging whether the position of the movable screen plate 4 at present accords with the cooking state, if so, returning to the step 2), and if not, driving the movable screen plate 4 to move to the corresponding position;

8) waiting for the time interval delta t, reading the position of the driving mechanism 76 or the movable screen plate 4 again, judging whether the moving mechanism adjusts the movable screen plate 4 to be in place, if so, returning to the step 2), and if not, repeating the step.

Claims

1. The utility model provides a range hood, includes collection petticoat pipe (1), sets up fan frame (2) and fan system (3) of setting in fan frame (2) in collection petticoat pipe (1) top, air intake (11) have been seted up on collection petticoat pipe (1), air intake (11) department is provided with fixed filter screen (5), its characterized in that: be located the below of fan system (3) in fan frame (2) and be provided with and move otter board (4), move otter board (4) and move about and keep transversely extending when moving to can change and move the air inlet state that is located the left side passageway and the right side passageway of fan system (3) below in otter board (4) and fixed filter screen (5) and fan frame (2).

2. The range hood of claim 1, wherein: the wind machine frame (2) is further internally provided with a movement mechanism used for driving the movable screen plate (4), the movement mechanism comprises a support (77) and a transmission rod (78), the support (77) can move in the left-right direction, the transmission rod (78) can move in the up-down direction relative to the support (77), and the transmission rod (78) is further connected and fixed with the movable screen plate (4).

3. The range hood of claim 2, wherein: the moving mechanism further comprises a driving rod (72), a connecting rod (73) and two first sliding blocks (74), wherein the driving rod (72) is fixedly arranged in the fan frame (2), the connecting rod (73) can rotate around an axis extending forwards and backwards, one end of the connecting rod (73) can slide along the left-right direction, and the other end of the connecting rod (73) can slide along the up-down direction; the transmission rod (78) is respectively connected with the two first sliding blocks (74) in a rotating mode, one first sliding block (74) is connected with the driving rod (72) in a sliding mode and can slide along the extending direction of the driving rod (72), and the other first sliding block (74) is connected with the connecting rod (73) in a sliding mode and can slide along the extending direction of the connecting rod (73); the rotational axis of the first slider (74) extends in the front-rear direction.

4. The range hood of claim 3, wherein: the moving mechanism further comprises a second sliding block (75), a first sliding rail (711) extending horizontally from left to right and a second sliding rail (712) extending vertically are fixedly arranged in the fan frame (2), the first sliding rail (711) and the second sliding rail (712) are mutually crossed, one end of the connecting rod (73) is connected with the first sliding rail (711) in a sliding mode through one of the second sliding blocks (75), the other end of the connecting rod (73) is connected with the second sliding rail (712) in a sliding mode through the other second sliding block (75), and a rotating shaft of the second sliding block (75) extends in the front-rear direction; still fixed third slide rail (714) of horizontal extension about being provided with in fan frame (2), thereby support (77) and third slide rail (714) sliding fit can move on left and right sides, be provided with fourth slide rail (771) of extending from top to bottom on support (77), transfer line (78) and fourth slide rail (771) sliding fit.

5. The range hood of claim 4, wherein: the movement mechanism further comprises a mounting plate (71) fixedly arranged in the fan frame (2), and the first sliding rail (711), the second sliding rail (712) and the third sliding rail (714) are arranged on the mounting plate (71).

6. The range hood of claim 3, wherein: the moving mechanism further comprises a driving mechanism (76), a supporting frame (713) is fixedly arranged in the fan frame (2), a certain gap is formed between the supporting frame (713) and the two sliding rails, the driving mechanism (76) is arranged on the supporting frame (713), the driving mechanism (76) is a rotary driving mechanism, and the output end of the driving mechanism (76) penetrates through the supporting frame (713) and is directly or indirectly connected with the driving rod (72).

7. The range hood according to claim 1 to 6, wherein: the movable screen plate (4) is a filter screen or a plate.

8. A control method of a range hood as claimed in any one of claims 1 to 7, characterized in that: the method comprises the following steps:

1) starting the range hood and operating in a default gear;

3.1.1) if ya is more than yb, controlling the movable screen plate (4) to move to the rightmost side, fully opening the channel at the left side, and then entering the step 3.4);

3.1.2) if ya is less than yb, controlling the movable screen plate (4) to move to the leftmost side, fully opening the right channel, and then entering the step 3.4);

3.2) if the difference between ya and yb is between m1 and m2, determining the left and right horizontal positions of the moving screen plate (4) according to ya and yb, and then entering the step 3.4);

3.3.1) if yd is more than y1, indicating a left and right big oil smoke scene, controlling the movable screen plate (4) to be at the middle position in the left and right direction, and enabling the gap between the movable screen plate and the fixed filter screen (5) to be larger, and then entering the step 4);

3.3.2) if yd is less than or equal to y1, representing a left-right small oil smoke scene, controlling the movable screen plate (4) to be positioned at the middle position in the left-right direction, and controlling the gap between the movable screen plate and the fixed filter screen (5) to be smaller, wherein the gap of the small oil smoke scene is smaller than that of the large oil smoke scene, and then entering the step 4);

3.4) taking the larger value of ya and yb as yd, comparing yd with a preset oil smoke concentration threshold value y1 or determining that the side with the larger oil smoke concentration is in a small oil smoke scene, a medium oil smoke scene or a large oil smoke scene according to preset data, controlling the gaps between the movable screen plate (4) and the fixed filter screen (5) to be sequentially increased in the three scenes, and then entering the step 4);

4) acquiring current position information of the moving screen plate (4);

5) and judging whether the position is matched with the current cooking scene, if so, returning to the step 2), otherwise, driving the moving screen plate (4) to the corresponding position, and after waiting for a time interval delta ta, returning to the step 4).

9. The control method of the range hood according to claim 8, characterized in that: in step 3), if

Judging that the difference between ya and yb exceeds m 2; if it is not

Then ya and yb are considered to differ less than m 1.

10. A control method of a range hood as claimed in any one of claims 1 to 7, characterized in that: the method comprises the following steps:

1) starting the range hood and operating in a default gear;

4) acquiring current position information of the moving screen plate (4);

6) acquiring the current flow Qm flowing through the fan system (3);

9) if Qm > Qd, go to step 11), if Qm < Qx, go back to step 6);

10) judging whether the gear or the rotating speed of a fan system (3) of the current range hood is the lowest or not, and if so, entering the step 11); if not, the 1 st gear is adjusted down, and the step 6) is returned;

11) judging whether the gap of an air inlet channel between the current movable screen plate (4) and the fixed filter screen (5) is minimum or not, and if so, prompting maintenance; if not, the movable screen plate (4) is lowered, the air inlet channel is reduced, and the step 6 is returned;

13) and (3) judging whether the air inlet channel gap between the current movable screen plate (4) and the fixed filter screen (5) is the maximum, if so, prompting to clean, otherwise, heightening the movable screen plate (4), enlarging the air inlet channel, and returning to the step 6).

11. The control method of the range hood according to claim 10, characterized in that: in step 3), if

Judging that the difference between ya and yb exceeds m 2; if it is not

Then ya and yb are considered to differ less than m 1.

12. A control method of a range hood as claimed in any one of claims 1 to 7, wherein: the method comprises the following steps:

1) standby of the range hood;

10) acquiring current position information of the moving screen plate (4);

11) judging whether the current position of the movable screen plate (4) is matched with the current cooking scene, if so, entering the step 12), otherwise, driving the movable screen plate (4) to the corresponding position, and returning to the step 10 after waiting for a time interval delta ta;

12) acquiring the flow Qm of the current fan system (3);

15) if Qm > Qd, go to step 16), if Qm < Qx, go to step 18);

16) judging whether the gear or the rotating speed of a fan system (3) of the current range hood is the lowest or not, and if so, entering the step 17); if not, the 1 st gear is adjusted down, and the step 12) is returned;

17) judging whether the gap between the current moving screen plate (4) and the fixed filter screen (5) is minimum or not, and if so, prompting maintenance; if not, the movable screen plate (4) is lowered, the gap is reduced, and the step 12 is returned;

18) judging whether the gear or the rotating speed of a fan system (3) of the current range hood is highest, if so, entering a step 19); if not, the 1 st gear is increased, and the step 12) is returned;

19) and (3) judging whether the gap between the movable screen plate (4) and the fixed filter screen (5) is the largest or not, if so, prompting to clean, otherwise, heightening the movable screen plate (4), enlarging the gap and returning to the step (12).

13. The control method of the range hood according to claim 12, wherein: in the step 9), when the cooking device is in a single-side cooking scene mainly taking oil smoke absorption on the left side or the right side, the movable screen plate (4) is positioned on the corresponding small oil smoke side, and the gap between the movable screen plate (4) and the fixed filter screen (5) at the large oil smoke position is larger than the gap between the movable screen plate (4) and the fixed filter screen (5) at the small oil smoke position; when the | kL-kR | is less than k theta, the movable screen plate (4) is positioned at the middle position in the left-right direction of the fan frame (2).

14. A control method of a range hood as claimed in any one of claims 1 to 7, characterized in that: the method comprises the following steps:

2) acquiring the current oil smoke amount of the left side and the right side;

4) the movable screen plate (4) is driven to move to one side of the small oil smoke, and the gap between the movable screen plate and the fixed filter screen (5) is determined according to the oil smoke amount on the left side and the right side;

5) waiting for the time interval delta t, reading the position of the movable screen plate (4) again, judging whether the position of the movable screen plate (4) accords with the cooking state, if so, returning to the step 2), and if not, repeating the step;

6) reading the position of the current moving screen plate (4);

7) judging whether the position of the current moving screen plate (4) accords with the cooking state, if so, returning to the step 2), and if not, driving the moving screen plate (4) to move to the corresponding position;

8) and waiting for the time interval delta t, reading the position of the movable screen plate (4) again, judging and judging whether the position of the movable screen plate (4) accords with the cooking state, returning to the step 2 if the position of the movable screen plate accords with the cooking state, and repeating the step if the position of the movable screen plate does not accord with the cooking state.