Guide centrifugal impeller and air fryer thereof

Abstract

The utility model relates to a guide centrifugal impeller and an air fryer thereof, which are designed for solving the technical problems of poorer energy efficiency, poorer wind field performance, poorer temperature field performance and poorer cooking effect caused by poorer structural design of hot air fan blades of the existing similar products. A body of the centrifugal fan blade is a stirring fan blade, and blades which are formed by stamping and bent towards one side of the bottom are distributed on a disc surface of the stirring fan blade at equal intervals by taking a shaft hole as a center; the stirring blade is characterized in that stamping holes which correspond to the blade in shape and are formed by stamping are formed in the disc face of the blade position of the stirring blade, the edge of the disc face of the stirring blade is provided with an R-angle guide edge which is formed by stamping and bending towards the blade bending forming side, and the arc height of the R-angle guide edge is 0.4-0.6 time of the height of the blade. The blade of the stirring fan blade is provided with at least two sub-blades with different sizes and the same height, the sub-blades of the blade comprise a first blade, a second blade and a third blade, and the heights of the first blade, the second blade and the third blade are the same and are sequentially reduced.

Description

Technical Field

[0001] The utility model relates to an impeller of an air fryer, in particular to a centrifugal impeller with a guide and an air fryer thereof. Background Art

[0002] An air fryer is a new household appliance that uses high-speed air circulation technology to fry food. Compared to traditional electric fryers, the food it cooks contains 80% less oil and fat. It's easy to clean, safe, and economical, making it highly popular. Currently, the performance of an air fryer is primarily determined by energy efficiency, temperature field, and wind field, with the fan structure and speed influencing all of these factors. For energy efficiency, the greater the air volume, the higher the convection coefficient, and the higher the energy efficiency of the heating tube. For wind field, the higher the wind speed, the smaller the turbulence diameter, and the more uniform the wind field. For temperature field, the primary energy transfer within the metal tube of the air fryer is primarily through forced convection. A more uniform wind field also results in a more uniform temperature field for the product. Existing air fryers primarily utilize non-enzymatic browning and rapid dehydration. The latter utilizes wind energy to remove a significant amount of moisture from the food's surface, rapidly dehydrating the food and raising its surface temperature, resulting in non-enzymatic browning and a crusty texture. This results in crispy exterior, tender interior, and a rich, charred flavor. Rapid dehydration, on the other hand, requires stronger wind for high-volume cooking scenarios like air drying (overall dehydration), baking French fries (45% dehydration), and grilling meat (surface dehydration). Currently, air fryers primarily utilize centrifugal impellers, which draw air from a central source and release air in a circular pattern, directly impacting the air fryer at close range. This results in significant fluid loss, especially when the fluid directly impacts the air fryer's walls. Existing centrifugal impellers, depending on their structure, are mainly divided into open radial centrifugal impellers and closed backward-curved centrifugal impellers. The advantages of open radial centrifugal impellers are low cost, high wind speed, and relatively small central vortex, but the disadvantage is relatively small air volume. The advantages of closed backward-curved centrifugal impellers are high wind speed and large air volume, making them suitable for flat air fryers or pizza machines. The disadvantages are high cost and large central vortex. To this end, some air fryers have made structural improvements to the open radial centrifugal impellers that serve as hot air blades, such as the application No. 202323207642.2 disclosed in the Chinese patent literature, with the application publication date of July 16, 2024, and the utility model name "Hot Air Assembly for Air Fryer and Air Fryer". However, the hot air guidance effect of the above-mentioned products and similar products within the cavity needs to be further improved, and therefore their structures need to be further improved. Summary of the Invention

[0003] To overcome the above-mentioned shortcomings, the present invention aims to provide an air fryer with a centrifugal impeller and a guide impeller, thereby resolving the technical problems of existing similar products, which suffer from poor energy efficiency, air flow field, and temperature field performance, as well as poor cooking results, due to the poor hot air impeller structure design. This objective is achieved through the following technical solution.

[0004] A centrifugal impeller with a guide, the main body of the centrifugal impeller is a stirring blade, the center of the disk of the stirring blade is provided with an axial hole, and the disk of the stirring blade is equidistantly distributed with blades formed by stamping and bent toward the bottom side with the axial hole as the center, and the blades and the disk are stamped and bent at 90 degrees; the key points of its structural design are that the disk of the stirring blade is provided with a punched hole corresponding to the shape of the blade, and the edge of the disk of the stirring blade is provided with an R-angle guide edge stamped and bent toward the side of the blade, and the arc height of the R-angle guide edge is between 0.4-0.6 times the height of the blade. The stirring blade of the above structure increases the guidance and controls the flow direction of the fluid by increasing the impeller fluid outlet, thereby achieving the effect of improving the wind field intensity. After the increase in guidance, the effective air volume in the air fryer increases by 15%. At the same time, the centrifugal impeller of the above structure is suitable for air fryers with top air outlet or air fryers with back air outlet. The air fryer with top air outlet is used as an example below.

[0005] A spacing M is provided between the blade of the stirring fan blade and the curved portion of the R-angle guide edge, and the spacing M is greater than 2 mm and less than 5 mm.

[0006] The blade of the stirring fan blade is provided with at least two sub-blades of different sizes and the same height. The sub-blades of the blade include a first blade, a second blade and a third blade. The heights of the first blade, the second blade and the third blade are the same and decrease in sequence.

[0007] The second and third blades of the stirring impeller are respectively in the shape of a right-angled trapezoid, and the first blade is respectively in the shape of a rectangle. The shapes of the first, second, and third blades correspond to the shapes of the punched holes. The above structure can maximize the through-hole flow direction of the disk surface and the blade guiding effect.

[0008] The disk of the stirring fan blade is provided with a punched groove formed by punching around the blade, the disk outside the shaft hole is provided with a punched ring, and the punched groove is provided with a punched reinforcement protrusion. The above structure can be set according to the strength requirements of the blade and the convenience of processing and production.

[0009] The heights h of the first blade, the second blade and the third blade of the stirring fan blade are greater than 10 mm and less than 12 mm.

[0010] The specific application of the stirring blade in an air fryer is as follows: the stirring blade and heating tube are installed in a groove at the bottom of the metal heat shield above the inner pot of the pot assembly in the machine body. The heating zone of the heating tube is located below the stirring blade. The notch at the bottom of the metal heat shield is aligned with the pot opening above the inner pot of the pot assembly in the machine body. The motor shaft at the shaded pole motor at the top of the metal heat shield is connected to the shaft hole of the stirring blade through the metal heat shield. The heating tube and shaded pole motor are connected to the PCB control assembly in the machine head via wiring. The metal heat shield is lined with the outer diameter of the pot assembly and the bottom of the pot assembly. The pot assembly is inserted into the machine body through an opening on one side of the lining. The heating tube can be a mosquito coil tube or a carbon tube as needed.

[0011] A plastic heat insulation cover is provided in the top head of the liner, and a cross flow fan blade is provided in the plastic heat insulation cover. The cross flow fan blade and the stirring fan blade are simultaneously connected to the motor shaft of the shaded pole motor at the top of the plastic heat insulation cover. The opening on one side of the inner cavity of the plastic heat insulation cover is connected to the exhaust port on one side of the machine body through the exhaust hood.

[0012] The handle on one side of the pot assembly extends out of an opening on one side of the inner lining of the oven body. Thus, the pot assembly can be placed in or out of the oven body via the handle, or the pot assembly can be placed in or out of the oven body via a door on one side of the inner lining of the oven body. In this case, the pot assembly can also be omitted from the oven body, and food can be placed in the oven body via a baking tray. The oven body is an air oven.

[0013] The blade structure of the utility model is reasonably designed, easy to manufacture, and has a wide range of applications. In particular, the energy efficiency, wind field, and temperature field are good, which is convenient for improving cooking effects. The utility model is suitable for use as a centrifugal impeller with a guide and an air fryer thereof, as well as a structural improvement of similar products. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a partial structural diagram of the utility model in use state, in which the dotted line is an embodiment of the machine body and the arrow is the guiding direction of the inner cavity.

[0015] Figure 2 yes Figure 1 Schematic diagram of the internal structure of the fuselage, where the dotted lines represent the lining and metal heat shield structure.

[0016] Figure 3 yes Figure 2 Schematic diagram of the three-dimensional enlarged structure of the stirring fan blade.

[0017] Figure 4 yes Figure 3 Schematic diagram of the bottom three-dimensional structure.

[0018] Figure 5 yes Figure 3 Schematic diagram of the top view structure.

[0019] Figure 6 yes Figure 3 Schematic diagram of the left view structure.

[0020] Figure 7 yes Figure 6 Schematic diagram of the cross-sectional structure.

[0021] Serial numbers and names of the accompanying drawings: 1. Machine body, 2. Pot body assembly, 3. Lining, 4. Metal heat insulation cover, 5. Stirring fan blade, 501. R-angle guide edge, 502. First blade, 503. Second blade, 504. Third blade, 6. Heating tube, 7. Shaded pole motor, 8. Plastic heat insulation cover, 9. Crossflow fan blade. DETAILED DESCRIPTION

[0022] Now, in conjunction with the accompanying drawings, the structure and use of the utility model are further described. Figure 1-Figure 7 As shown, the body with the guide centrifugal impeller is a stirring blade 5, and the stirring blade and the heating tube 6 are arranged in the groove at the bottom of the metal heat insulation cover 4 above the inner pot of the pot body assembly 2 in the machine body 1. The heating area of ​​the heating tube is located below the stirring blade, and the notch at the bottom of the metal heat insulation cover is aligned with the pot mouth above the inner pot of the pot body assembly in the machine body. The motor shaft at the shaded pole motor 7 on the top of the metal heat insulation cover is connected to the shaft hole of the stirring blade through the metal heat insulation cover. The heating tube and the shaded pole motor are connected to the PCB control assembly in the machine head through the line. The metal heat insulation cover and the outer diameter of the pot body assembly and the bottom of the pot body assembly are provided with an inner lining 3, and the pot body assembly is placed in the machine body through an opening on one side of the inner lining. A plastic heat insulation cover 8 is provided in the top head of the above-mentioned lining, and a cross flow fan blade 9 is provided in the plastic heat insulation cover. The cross flow fan blade and the stirring fan blade are simultaneously connected to the motor shaft of the shaded pole motor at the top of the plastic heat insulation cover. The opening on one side of the inner cavity of the plastic heat insulation cover is connected to the exhaust port on one side of the machine body through the exhaust hood; the handle on one side of the pot body assembly extends out of the opening on one side of the lining at the machine body.

[0023] The center of the disk of the stirring fan blade is provided with an axial hole, and the disk of the stirring fan blade is equidistantly distributed with blades formed by stamping and bent toward the bottom side with the axial hole as the center, and the blades and the disk are formed by stamping and bending at 90 degrees; the disk of the stirring fan blade is provided with a punching hole corresponding to the shape of the blade and punched, and the edge of the disk of the stirring fan blade is provided with an R-angle guide edge 501 punched and bent toward the side of the blade bending, and the arc height of the R-angle guide edge is between 0.4-0.6 times the height of the blade. There is a spacing M between the blade of the stirring fan blade and the bending part of the R-angle guide edge, and the spacing M is greater than 2mm and less than 5mm. The blade of the stirring fan blade is provided with at least two sub-blades of different sizes and the same height, and the sub-blades of the blade include a first blade 502, a second blade 503 and a third blade 504, and the heights of the first blade, the second blade and the third blade are the same and decrease in sequence. The second and third blades of the stirring blade are respectively in the shape of a right-angled trapezoid, and the first blade is respectively in the shape of a rectangle. The shapes of the first, second, and third blades correspond to the shapes of the punched holes. The height h of the first, second, and third blades of the stirring blade is greater than 10 mm and less than 12 mm. The disk surface of the stirring blade is provided with a punched groove formed by punching around the blade, and the disk surface outside the shaft hole is provided with a punched ring, and the punched groove is provided with a reinforcing protrusion formed by punching.

[0024] When in use, take out the pot body assembly through the handle, put food into the inner pot or grill of the pot body assembly, and then put the pot body assembly back into the body through the handle; finally, press the corresponding cooking button on the control panel of the PCB control assembly, and the corresponding food in the pot body assembly can be automatically processed and cooked.

[0025] In summary, the above-mentioned stirring blade increases the guidance and control of the fluid flow direction by adding a fluid outlet at the impeller, thereby achieving the effect of increasing the wind field intensity; wherein, the inner side of the R-angle guide edge of the stirring blade guides the fluid at the impeller, and after the guidance is increased, the effective air volume in the air explosion increases by 15%. The arc height at the R-angle guide edge of the above-mentioned stirring blade should be controlled between 0.4-0.6 times the blade or overall height L. There is a spacing M between the blade of the stirring blade and the curved part of the R-angle guide edge, 2mm≤M≤5mm. The above size results in less fluid loss on the wall. If the size is too small, the fluid loss will be greater. If the size is too large, the fluid will leave the blade wall before turning, and it will not play the role of controlling the flow direction.

[0026] The above description is intended to illustrate the technical means of the present invention and is not intended to limit its scope. Any obvious improvements or substitutions made by those skilled in the art, in combination with existing common knowledge, to the present invention fall within the scope of the claims. For example, the spacing M and height h described above are adjusted based on the actual dimensions of the air fryer. The above structure is based on the dimensions of a conventional air fryer.

Claims

1. A centrifugal impeller with a guide, the main body of the centrifugal impeller with a guide is a stirring fan blade (5), the center of the disk of the stirring fan blade is provided with an axial hole, the disk of the stirring fan blade is equidistantly distributed with blades formed by stamping and bent to one side of the bottom with the axial hole as the center, and the blades and the disk are stamped and bent at 90 degrees; characterized in that The disk surface of the stirring fan blade (5) is provided with a punching hole corresponding to the shape of the blade and formed by punching, and the edge of the disk surface of the stirring fan blade is provided with an R-angle guide edge (501) punched and bent toward the side of the blade bending, and the arc height at the R-angle guide edge is between 0.4 and 0.6 times the height of the blade.

2. The centrifugal impeller with guide according to claim 1, characterized in that A spacing M is provided between the blade of the stirring fan blade (5) and the curved portion of the R-angle guide edge (501), and the spacing M is greater than 2 mm and less than 5 mm.

3. The centrifugal impeller with guide according to claim 1, characterized in that The stirring impeller (5) is provided with at least two sub-blades of different sizes and the same height, the sub-blades of the blade comprising a first blade (502), a second blade (503) and a third blade (504), and the first blade, the second blade and the third blade have the same height and decrease in sequence.

4. The centrifugal impeller with guide according to claim 3, characterized in that The second blade (503) and the third blade (504) of the stirring fan blade (5) are respectively in the form of a right-angled trapezoid, and the first blade (502) is respectively in the form of a rectangle, and the shapes of the first blade, the second blade and the third blade correspond to the shapes of the punched holes.

5. The centrifugal impeller with guide according to claim 3, characterized in that The height h of the first blade (502), the second blade (503) and the third blade (504) at the blades of the stirring fan blade (5) is greater than 10 mm and less than 12 mm.

6. The centrifugal impeller with guide according to claim 1, characterized in that The disk surface of the stirring fan blade (5) is provided with a punching groove formed by punching around the blade, the disk surface outside the shaft hole is provided with a punching ring, and the punching groove is provided with a reinforcing protrusion formed by punching.

7. An air fryer using the centrifugal impeller according to any one of claims 1 to 6, characterized in that The stirring fan blade (5) and the heating tube (6) are arranged in a groove at the bottom of the metal heat insulation cover (4) above the inner pot of the pot body assembly (2) in the machine body (1); the heating area of ​​the heating tube is located below the stirring fan blade; the notch at the bottom of the metal heat insulation cover is aligned with the pot mouth above the inner pot of the pot body assembly in the machine body; the motor shaft of the shaded pole motor (7) at the top of the metal heat insulation cover is connected to the shaft hole of the stirring fan blade through the metal heat insulation cover; the heating tube and the shaded pole motor are connected to the PCB control assembly in the machine head through a line; the metal heat insulation cover and the outer diameter of the pot body assembly and the bottom of the pot body assembly are provided with an inner lining (3); the pot body assembly is placed in the machine body through an opening on one side of the inner lining.

8. The air fryer according to claim 7, characterized in that A plastic heat insulation cover (8) is provided in the top head of the liner (3), and a cross flow fan blade (9) is provided in the plastic heat insulation cover. The cross flow fan blade and the stirring fan blade (5) are simultaneously connected to the motor shaft of the shaded pole motor (7) at the top of the plastic heat insulation cover. An opening on one side of the inner cavity of the plastic heat insulation cover is connected to an exhaust port on one side of the machine body (1) through an exhaust cover.

9. The air fryer according to claim 7, characterized in that The handle on one side of the pot body assembly (2) extends out of an opening on one side of the inner lining of the machine body (1).

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