Variable frequency range hood with self-cleaning air duct

Abstract

This invention relates to the field of range hood technology, specifically disclosing a variable frequency range hood with self-cleaning ductwork. The range hood includes a main body with a duct installed on its upper part. A smoke pipe is connected to the upper part of the duct, and a cleaning mechanism is installed inside the duct. The cleaning mechanism includes a rotating shaft rotatably connected to the duct, with a scraper fixed to its lower end. The internal duct is tubular, and the scraper is attached to the inner wall of the duct on both sides. This invention achieves efficient cleaning by combining electric heating to soften grease with mechanical scraping by a rotating scraper. Grease is guided to the grease boxes on both sides through a barrier pipe, avoiding secondary pollution and shortening the grease drainage path. The cleaning mechanism is driven by the exhaust airflow to a fan, requiring no additional power. A linkage sealing plate switches the airflow channel, ensuring that exhaust and cleaning do not interfere with each other. The scraper automatically adjusts its angle as it rotates, driven by a lifting frame, forming a multi-stage scraping motion that significantly improves cleaning coverage and stain removal.

Description

Technical Field

[0001] This invention relates to the field of range hood technology, and in particular to a variable frequency range hood with self-cleaning air duct. Background Technology

[0002] A range hood (also known as a kitchen exhaust fan or cooking hood) is a household appliance installed above the kitchen stove. Its main purpose is to remove cooking fumes, steam, odors, and some heat generated during cooking to keep the kitchen air fresh, reduce grease buildup, and improve indoor air quality. The high-temperature cooking fumes gradually cool as they pass through the air duct, causing the grease to condense and adhere to the inner walls of the duct. Over time, this grease buildup can clog the duct, increasing airflow resistance and reducing the effectiveness of fume extraction. The grease can also ferment and oxidize, emitting unpleasant odors, requiring the motor to operate at higher power, and accelerating its aging.

[0003] While most existing range hoods possess self-cleaning functions, grease collection typically relies on an oil cup or filter located at the bottom of the unit. Grease must flow down a relatively long path, during which it is prone to dripping, splashing, or adhering to internal components such as the fan and motor, leading to equipment contamination, performance degradation, and cleaning difficulties. The cleaning methods are simplistic, relying solely on filter interception or electric heating to melt grease, lacking effective mechanical scraping structures and proving ineffective against stubborn grease buildup. Therefore, this invention proposes a variable frequency range hood with a self-cleaning duct to address the problems mentioned in the background section. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by proposing a variable frequency range hood with a self-cleaning air duct.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A variable frequency range hood with self-cleaning duct includes a range hood body, an air duct installed on the upper part of the range hood body, a smoke pipe connected to the upper part of the air duct, a cleaning mechanism inside the air duct, the cleaning mechanism including a rotating shaft rotatably connected to the air duct, a scraper fixed at the lower end of the rotating shaft, the internal channel of the air duct being tubular, both sides of the scraper being attached to the inner wall of the air duct, a ring seat sliding up and down on the rotating shaft on the upper side of the scraper, a lifting frame fixed outside the ring seat, and several scraper blades on both sides of the lifting frame; A wind box is installed on one side of the outside of the air duct. The wind box is connected to the inside of the air duct, and an air duct is connected between the upper part of the wind box and the flue. A semi-circular sealing plate II, which is connected to the air duct, is provided at the opening between the wind box and the air duct. A semi-circular sealing plate I, which is connected to the air duct, is provided at the opening between the air duct and the upper flue. A rotating rod is rotatably connected inside the air duct, and a wind wheel located inside the wind box is fixed at the outer end of the rotating rod.

[0006] Preferably, a baffle tube is installed inside the air duct, the outer diameter of the baffle tube is smaller than the inner diameter of the air duct, and an annular groove is formed between the lower outer part of the baffle tube and the air duct.

[0007] Preferably, an oil box is provided on both the left and right sides of the annular groove. The oil box is semi-circular and slides inside and outside the lower part of the air duct.

[0008] Preferably, the air duct and the flue are connected by a semi-circular opening corresponding to the first semi-circular sealing plate, and the air box and the air duct are connected by a semi-circular opening corresponding to the second semi-circular sealing plate.

[0009] Preferably, a toothed end face ring is fixed on the lower side of the semicircular sealing plate, and an end face gear that meshes with the upper end face ring is fixed on the inner side of the second semicircular sealing plate. A motor connected to the second semicircular sealing plate is installed inside the air box.

[0010] Preferably, a bevel gear one is fixed to the inner end of the rotating rod, and a bevel gear two that meshes with the bevel gear one is fixed to the upper end of the rotating shaft.

[0011] Preferably, a compression spring sleeved around the circumference of the rotating shaft is provided between the ring seat and the lower scraper, and a contact block fixed in the air duct is provided on the upper side of the ring seat, with grooves corresponding to the contact block opened on both the left and right sides of the upper side of the ring seat.

[0012] Preferably, the scraper blade is rotatably connected to the scraper frame, and the scraper frame has several slots on both sides corresponding to the scraper blade.

[0013] Preferably, a number of electric heating rods are installed inside the air duct at the location corresponding to the cleaning mechanism, and the number of electric heating rods are arranged in a ring array inside the air duct.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. The present invention integrates an automatic cleaning mechanism inside the air duct. The scraper scrapes off the oil stains by rotating against the inner wall, and the electric heating rods arranged in a ring heat and soften the attached oil stains, making the cleaning process more efficient and thorough. After being scraped off, the oil stains flow down the inner wall, are guided to the ring groove by the barrier tube, and finally collect in the oil boxes on both sides, avoiding the backflow of oil stains or contamination of the lower structure of the range hood. At the same time, it shortens the oil stain discharge path, making it easier to collect and clean. 2. The entire cleaning mechanism of this invention does not require an additional power source. It cleverly utilizes the airflow during normal operation of the range hood to drive the impeller inside the air box, and drives the cleaning components to operate through a gear transmission system. The passage between the air duct, the smoke pipe, and the air box is switched and controlled by two linked semi-circular sealing plates. In the cleaning or normal smoke exhaust state, one sealing plate is driven to rotate by a motor, and the other sealing plate is driven to move synchronously by the meshing relationship between the end face gear and the gear ring, thereby ensuring that the airflow path is always reasonably open or closed, effectively preventing oil fume leakage or crossflow, and ensuring smoke exhaust efficiency and cleaning effect. 3. The scraper design in the cleaning mechanism of this invention has dynamic adjustment capability. During the rotation of the scraper frame, the periodic contact between the contact block and the groove and the elastic action of the spring cause the lifting frame to move up and down, thereby driving the scraper to change the angle at different positions. When rising, it is vertical to reduce resistance, and when falling, it is horizontal to enhance the scraping force. This biomimetic multi-stage scraping mechanism significantly improves the cleaning coverage and decontamination ability of different height areas of the inner wall of the air duct. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of a variable frequency range hood with self-cleaning air duct proposed in this invention; Figure 2 This is a schematic cross-sectional view of a variable frequency range hood with self-cleaning ductwork proposed in this invention. Figure 1 ; Figure 3 This is a schematic cross-sectional view of a variable frequency range hood with self-cleaning ductwork proposed in this invention. Figure 2 ; Figure 4 This is a front cross-sectional view of a variable frequency range hood with self-cleaning air duct proposed in this invention. Figure 5 This is a side cross-sectional view of a variable frequency range hood with self-cleaning air duct proposed in this invention. Figure 6 This is a schematic diagram of the cleaning mechanism in a variable frequency range hood with self-cleaning air duct proposed in this invention.

[0016] In the diagram: 1. Range hood body; 2. Air duct; 3. Oil box; 4. Smoke pipe; 5. Air box; 6. Air duct; 7. Barrier pipe; 8. Cleaning mechanism; 801. Rotary shaft; 802. Scraper; 803. Lifting frame; 804. Ring seat; 805. Groove; 806. Compression spring; 807. Scraper blade; 808. Slotting; 9. End face gear ring; 10. Semicircular sealing plate one; 11. Semicircular sealing plate two; 12. Wind wheel; 13. End face gear; 14. Rotating rod; 15. Bevel gear one; 16. Bevel gear two; 17. Ring groove; 18. Contact block; 19. Electric heating rod. Detailed Implementation

[0017] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0018] Reference Figure 1-6A variable frequency range hood with self-cleaning duct includes a range hood body 1, an air duct 2 installed on the upper part of the range hood body 1, a smoke pipe 4 connected to the upper part of the air duct 2, a cleaning mechanism 8 inside the air duct 2, the cleaning mechanism 8 including a rotating shaft 801, the rotating shaft 801 being rotatably connected to the air duct 2, a scraper 802 fixed at the lower end of the rotating shaft 801, the internal channel of the air duct 2 being tubular, the scraper 802 being attached to the inner wall of the air duct 2 on both sides, a baffle tube 7 installed inside the air duct 2, the outer diameter of the baffle tube 7 being smaller than the inner diameter of the air duct 2, and an annular groove 17 being formed between the lower outer part of the baffle tube 7 and the air duct 2, an oil box 3 being provided on both sides of the annular groove 17, the oil box 3 being semi-circularly annular, the oil box 3 sliding inside and outside the lower part of the air duct 2, and a plurality of electric heating rods 19 being installed inside the air duct 2 corresponding to the position of the cleaning mechanism 8, the plurality of electric heating rods 19 being arranged in a ring array inside the air duct 2; When cleaning the inside of the range hood duct 2, the cleaning mechanism 8 inside the duct 2 is activated to clean the inner wall of the duct 2. With the help of the annularly arranged electric heating rods 19, the electric heating rods 19 heat and melt the oil stains attached to the inner wall. With the help of the scraper 802 structure that rotates and scrapes the inner wall, the oil stains inside the duct 2 can be cleaned quickly. The oil stains flow down from the inner wall and are blocked by the lower baffle tube 7, flowing into the formed annular groove 17 and entering the oil boxes 3 on both sides below. Unlike the traditional range hood body 1, the oil collection box of this range hood is installed at the lower part of the duct 2. This not only saves the cleaning path of the oil stains, but also prevents the oil stains from flowing to the lower filter screen and causing pollution at the bottom of the range hood. A bellows 5 is installed on one side of the outside of the air duct 2. The bellows 5 is connected to the inside of the air duct 2. A duct 6 is connected between the upper part of the bellows 5 and the flue 4. A semi-circular sealing plate 211 is provided at the opening between the bellows 5 and the air duct 2, and a semi-circular sealing plate 10 is provided at the opening between the air duct 2 and the upper flue 4, and a semi-circular opening corresponding to the semi-circular sealing plate 10 is provided between the air duct 2 and the flue 4. A semi-circular opening corresponding to the semi-circular sealing plate 10 is provided between the bellows 5 and the air duct 2. An end face toothed ring 9 is fixed on the lower side of the semi-circular sealing plate 10, and an end face gear 13 that meshes with the upper end face toothed ring 9 is fixed on the inner side of the semi-circular sealing plate 21. A motor connected to the semi-circular sealing plate 21 is installed inside the bellows 5. Before cleaning, the motor inside the air box 5 needs to be started. The motor drives the connected semi-circular sealing plate 11 to rotate half a turn, so that the originally blocked semi-circular opening is opened. When the range hood body 1 is working, the airflow can enter the upper flue 4 through the air box 5 on one side. When the semi-circular sealing plate 11 rotates, the semi-circular sealing plate 11 drives the upper meshing end face gear 9 through the end face gear 13 fixed on the outside. The end face gear 9 drives the upper fixed semi-circular sealing plate 10 to rotate. The semi-circular sealing plate 10 closes the originally open semi-circular opening, so that the airflow of the range hood working at this time can only enter the flue 4 through the air box 5 on one side. A ring seat 804 is provided on the upper side of the scraper 802 and slides up and down on the rotating shaft 801. A lifting frame 803 is fixed on the outer side of the ring seat 804. Several scraper blades 807 are provided on both sides of the lifting frame 803. A rotating rod 14 is rotatably connected inside the air duct 2. A wind wheel 12 located in the air box 5 is fixed at the outer end of the rotating rod 14. A bevel gear 15 is fixed at the inner end of the rotating rod 14. A bevel gear 16 meshing with the bevel gear 15 is fixed at the upper end of the rotating shaft 801. A compression spring 806 is provided between the ring seat 804 and the lower scraper 802 and is sleeved on the periphery of the rotating shaft 801. A contact block 18 is provided on the upper side of the ring seat 804 and fixed in the air duct 2. Grooves 805 corresponding to the contact block 18 are opened on the left and right sides of the upper side of the ring seat 804. The scraper blades 807 are rotatably connected to the scraper 802. Several slots 808 corresponding to the scraper blades 807 are opened on both sides of the scraper 802. As the airflow passes through the bellows 5 and enters the flue 4, the airflow disturbs the rotation of the impeller 12 inside the bellows 5. The impeller 12 drives the connected rotating rod 14 to rotate, which in turn drives the inner fixed bevel gear 15 to rotate. The bevel gear 15, through the meshing bevel gear 16, drives the rotating shaft 801 of the air duct 2 to rotate. The rotating shaft 801 drives the lower scraper 802 to rotate, thus cleaning the inner wall of the air duct 2. The lifting frame 803 structure on the scraper 802 rotates along with it. During the rotation of the lifting frame 803 structure, the grooves 805 on both sides of its upper ring seat 804 contact the corresponding contact blocks 18, cooperating with the lower extrusion... The compression spring 806 enables the lifting frame 803 to slide up and down on the scraper frame 802 as the lifting frame 803 rotates with the scraper frame 802. Several scraper blades 807 on both sides of the lifting frame 803 move accordingly. Due to the setting of the scraper blades 807 and the corresponding slots 808 on the scraper frame 802, the scraper blades 807 rotate downwards to vertical position as they rise with the lifting frame 803, and rotate upwards to horizontal position as the lifting frame 803 descends. This structure of the lifting frame 803, which moves with the scraper frame 802, can scrape away dirt layer by layer, greatly improving the cleaning effect and efficiency of the inner wall of the air duct 2.

[0019] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A variable frequency range hood with self-cleaning duct, comprising a range hood body (1), characterized in that, The range hood body (1) is equipped with an air duct (2) on the upper part, and a smoke pipe (4) is connected to the upper part of the air duct (2). A cleaning mechanism (8) is provided inside the air duct (2). The cleaning mechanism (8) includes a rotating shaft (801), which is rotatably connected to the air duct (2). A scraper (802) is fixed at the lower end of the rotating shaft (801). The air duct (2) has a tubular internal channel shape. Both sides of the scraper (802) are attached to the inner wall of the air duct (2). A ring seat (804) that slides up and down on the rotating shaft (801) is provided on the upper side of the scraper (802). A lifting frame (803) is fixed on the outer side of the ring seat (804). Several scraper blades (807) are provided on both sides of the lifting frame (803). A bellows (5) is installed on one side of the outside of the air duct (2). The bellows (5) is connected to the inside of the air duct (2). A duct (6) is connected between the upper part of the bellows (5) and the flue (4). A semi-circular sealing plate (11) is provided at the opening between the bellows (5) and the air duct (2) and is connected to the inside of the air duct (2). A semi-circular sealing plate (10) is provided at the opening between the air duct (2) and the upper flue (4) and is connected to the inside of the air duct (2). A rotating rod (14) is rotatably connected inside the air duct (2). A wind wheel (12) located inside the bellows (5) is fixed at the outer end of the rotating rod (14).

2. The variable frequency range hood with self-cleaning duct as described in claim 1, characterized in that, The air duct (2) is equipped with a baffle tube (7), the outer diameter of the baffle tube (7) is smaller than the inner diameter of the air duct (2), and an annular groove (17) is formed between the lower outer part of the baffle tube (7) and the air duct (2).

3. The variable frequency range hood with self-cleaning duct as described in claim 2, characterized in that, Oil boxes (3) are provided on both the left and right sides of the annular groove (17). The oil boxes (3) are semi-circular rings and slide inside and outside the lower part of the air duct (2).

4. The variable frequency range hood with self-cleaning duct as described in claim 1, characterized in that, The air duct (2) and the flue (4) are connected by a semi-circular opening of a corresponding semi-circular sealing plate one (10), and the air box (5) and the air duct (2) are connected by a semi-circular opening of a corresponding semi-circular sealing plate two (11).

5. The variable frequency range hood with self-cleaning duct as described in claim 1, characterized in that, The lower side of the first semicircular sealing plate (10) is fixed with an end face gear ring (9), and the inner side of the second semicircular sealing plate (11) is fixed with an end face gear (13) that meshes with the upper end face gear ring (9). The air box (5) is equipped with a motor that connects to the second semicircular sealing plate (11).

6. The variable frequency range hood with self-cleaning duct as described in claim 1, characterized in that, The inner end of the rotating rod (14) is fixed with a bevel gear one (15), and the upper end of the rotating shaft (801) is fixed with a bevel gear two (16) that meshes with the bevel gear one (15).

7. The variable frequency range hood with self-cleaning duct as described in claim 1, characterized in that, A compression spring (806) is provided between the ring seat (804) and the lower scraper (802) and sleeved around the rotating shaft (801). A contact block (18) is provided on the upper side of the ring seat (804) and fixed in the air duct (2). Grooves (805) corresponding to the contact block (18) are provided on both the left and right sides of the upper side of the ring seat (804).

8. The variable frequency range hood with self-cleaning duct as described in claim 1, characterized in that, The scraper (807) is rotatably connected to the scraper frame (802), and the scraper frame (802) has several slots (808) on both sides corresponding to the scraper (807).

9. The variable frequency range hood with self-cleaning duct as described in claim 1, characterized in that, Several electric heating rods (19) are installed inside the air duct (2) at the position corresponding to the cleaning mechanism (8), and the several electric heating rods (19) are arranged in a ring array inside the air duct (2).

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