Front air guide ring for pipeline fan

Abstract

A front air guide ring for a pipeline fan comprises a first air guide ring body, a second air guide ring body and a third air guide ring body which extend in the air outlet direction, the diameter of the second air guide ring body is smaller than that of the first air guide ring body and that of the second air guide ring body, and the inner surfaces of the first air guide ring body, the second air guide ring body and the third air guide ring body are in arc transition connection. And a wing-shaped section protruding towards the inside of the hole is formed. The air guide ring has the advantages that the section of the air guide ring is designed to be in a wing shape. According to the Bernoulli principle, when air flows through the wing-shaped air guide ring, a similar common siphon effect can be generated, and surrounding air is sucked into the fan. Therefore, the wing-shaped air guide ring can remarkably increase the air volume of the fan, and the overall ventilation effect is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of ventilation equipment, in particular to a front air guide ring for a duct fan. Background Art

[0002] An axial flow fan is a common type of fan. When it works, the air flow passes through the impeller along the axial direction of the impeller shaft, and has characteristics such as low pressure and large flow rate. It is widely used in cooling and ventilation in air conditioning equipment and household electrical appliances. An ordinary axial flow fan usually includes a guide vane ring and an axial flow impeller arranged in the guide vane ring. In order to ensure the normal operation of the axial flow fan, a reasonable radial tip clearance needs to be left between the axial flow impeller and the guide vane ring. The radial tip clearance has a great influence on the head, efficiency and noise performance of the axial flow fan.

[0003] There are some obvious defects in the existing axial flow fans in practical applications:

[0004] 1. During the operation of the axial flow fan, there will be a large pressure difference between the pressure surface and the suction surface of the axial flow impeller. When the radial tip clearance of the axial flow fan is too large, the pressure difference between the pressure surface and the suction surface will cause the air flow to flow back along the radial tip clearance, resulting in tip leakage loss. This backflow not only reduces the efficiency of the axial flow fan, but also increases the energy consumption.

[0005] 2. Due to tip leakage, the air flow cannot effectively pass through the impeller, resulting in a decrease in the overall efficiency of the fan. The axial flow fan cannot achieve the designed optimal performance during actual operation, especially in application scenarios that require efficient ventilation and cooling.

[0006] 3. The tip backflow phenomenon will also cause instability of the air flow, generating additional turbulence and eddy currents, thereby increasing the noise of the axial flow fan. Therefore, it is necessary to make further improvements to it. Content of the Utility Model

[0007] The purpose of the utility model is to overcome the defects of the existing technology, and provide a front air guide ring for a duct fan with a simple structure, convenient use, which reduces tip leakage by optimizing the design of the air guide structure, improves the efficiency of the fan, and can effectively increase the air volume of the fan.

[0008] The purpose of the utility model is realized in the following way: A front air guide ring for a duct fan, which includes a first air guide ring extending towards the air outlet direction, a second air guide ring and a third air guide ring. The diameter of the second air guide ring is set smaller than that of the first air guide ring and the second air guide ring. The inner surfaces of the first air guide ring, the second air guide ring and the third air guide ring are connected by an arc transition, forming an airfoil section protruding towards the inner direction of the hole.

[0009] Furthermore, an air inlet area in the shape of an arc horn with a larger outer diameter and a smaller inner diameter is formed between the first air guide ring and the second air guide ring, and an air outlet area in the shape of an arc horn with a larger outer diameter and a smaller inner diameter is formed between the second air guide ring and the third air guide ring.

[0010] Furthermore, the outer cylindrical surfaces of the first air guide ring, the second air guide ring and the third air guide ring are in the shape of concave annular grooves, and a plurality of reinforcing rib pieces are axially arranged in the annular grooves.

[0011] Furthermore, the maximum diameter of the first air guide ring is larger than the diameter of the third air guide ring. After the air guide ring is assembled with the duct fan, the first air guide ring covers the end face of the air inlet of the duct fan, and the maximum diameter of the third air guide ring is smaller than the inner diameter of the duct fan, so that the third air guide ring is embedded in the inner wall of the duct fan.

[0012] Furthermore, the first air guide ring, the second air guide ring and the third air guide ring are integrally injection-molded from a plastic material.

[0013] The beneficial effects of the present utility model are as follows: 1. The structure is simple, the production cost is low, and the market competitiveness is improved.

[0014] 2. The cross-section of the air guide ring in the present utility model is designed as an airfoil. According to Bernoulli's principle, when air flows through the airfoil-shaped air guide ring, a so-called siphon effect will be generated, and the surrounding air will be attracted into the fan. Therefore, the airfoil-shaped air guide ring can significantly increase the air volume of the fan and improve the overall ventilation effect.

[0015] 3. The airfoil-shaped air guide ring not only increases the air volume of the fan, but also can improve the air pressure of the fan, so that the air can be better discharged outdoors. When the outdoor wind backflow is serious, an air pressure opposite to the exhaust direction of the fan will be generated, resulting in the backflow of the air flow in the fan through the gap between the fan blade and the inner wall of the fan body. When the backflow air flow encounters the airfoil-shaped air guide ring, it needs to "climb the slope" upward and meet the air entering the fan. Due to the arc design of the airfoil-shaped air guide ring, the backflow air flow will rotate back and be discharged outdoors again, thus ensuring the strong exhaust capacity of the fan and effectively solving the backflow problem.

[0016] 4. The setting of the air guide ring reduces the radial gap between the air guide ring and the inner fan blade of the duct fan. There is a pressure difference between the pressure surface and the suction surface of the axial flow fan blade, so that part of the air flow leaks through the radial gap at the blade tip. The leaked air is redirected by the air guide ring and re-incorporated into the air flow inside the air guide ring, which can effectively solve the problem of leakage loss in the radial gap at the blade tip of the axial flow fan under high static pressure conditions. Description of the Drawings

[0017] Figure 1 It is an assembly usage effect diagram of the present utility model and the duct fan.

[0018] Figure 2This is an exploded view of the structure of the present utility model and the duct fan.

[0019] Figure 3 This is a cross-sectional view of the assembled structure of the present utility model and the duct fan.

[0020] Figure 4 This is a schematic diagram of the structure of the present utility model.

[0021] Figure 5 This is a cross-sectional view of the structure of the present utility model. Specific embodiments

[0022] The following further specifically describes the present utility model with reference to the accompanying drawings. A front air guide ring for a duct fan includes a first air guide ring 1 extending towards the air outlet direction, a second air guide ring 2, and a third air guide ring 3. The diameter of the second air guide ring 2 is set smaller than the diameters of the first air guide ring 1 and the second air guide ring 2. The inner surfaces of the first air guide ring 1, the second air guide ring 2, and the third air guide ring 3 are connected in an arc transition, forming an airfoil section protruding towards the inside of the hole.

[0023] In one embodiment: An arc-shaped trumpet-shaped air inlet area 4 with a large outer and small inner shape is formed between the first air guide ring 1 and the second air guide ring 2, and an arc-shaped trumpet-shaped air outlet area 5 with a large outer and small inner shape is formed between the second air guide ring 2 and the third air guide ring 3.

[0024] In one embodiment: The outer cylindrical surfaces of the first air guide ring 1, the second air guide ring 2, and the third air guide ring 3 are in a concave annular groove shape, and a plurality of reinforcing rib pieces 6 are axially extended and arranged in the annular groove.

[0025] In one embodiment: The maximum diameter of the first air guide ring 1 is greater than the diameter of the third air guide ring 3. After the present air guide ring is assembled with the duct fan 7, the first air guide ring 1 covers the end face of the air inlet of the duct fan 7, and the maximum diameter of the third air guide ring 3 is smaller than the inner diameter of the duct fan 7, so that the third air guide ring 3 is embedded in the inner wall of the duct fan 7.

[0026] In one embodiment: The first air guide ring 1, the second air guide ring 2, and the third air guide ring 3 are integrally injection-molded from a plastic material.

[0027] Working principle: As Figures 1 - 3 shown, the front air guide ring in this case is used as a separate accessory and is installed at the air inlet end of the duct fan. Among them, in order to ensure the stability of the installation of the present air guide ring and the duct fan, the maximum diameter of the first air guide ring 1 described in this case is greater than the diameter of the third air guide ring 3. After the present air guide ring is assembled with the duct fan 7, the first air guide ring 1 covers the end face of the air inlet of the duct fan 7, and the maximum diameter of the third air guide ring 3 is smaller than the inner diameter of the duct fan 7, so that the third air guide ring 3 is embedded in the inner wall of the duct fan 7.

[0028] After the air guide ring is installed, the radial clearance between the air guide ring and the inner fan blades of the duct fan is reduced. There is a pressure difference between the pressure side and the suction side of the axial-flow fan blades, causing some airflows to leak through the radial clearance at the blade tip. The leaked air is redirected through the air guide ring and re-incorporated into the airflows inside the air guide ring, effectively solving the problem of leakage loss at the radial clearance at the blade tip under high static pressure conditions of the axial-flow fan.

[0029] When the duct fan operates, a negative pressure is generated inside the duct, and air enters the fan through the air guide ring. Among them, the cross-section of the air guide ring in the present invention is designed as an airfoil. When air flows through the airfoil-shaped air guide ring, according to Bernoulli's principle, a phenomenon similar to the siphon effect will occur. The airfoil structure causes the airflow to accelerate when passing through, resulting in the surrounding air being attracted into the fan. Since the airfoil-shaped air guide ring optimizes the airflow path, it can effectively reduce air resistance, thereby significantly increasing the air volume of the fan.

[0030] Furthermore: When air passes through the airfoil-shaped air guide ring, as Figure 3 、 5 shown, due to the airfoil cross-section design of the air guide ring, the area of the ventilation cross-section decreases, and the air velocity V increases. According to Bernoulli's principle formula: p + 1 / 2ρv² + ρgh = C (where p is the pressure at a certain point in the fluid, v is the velocity of the fluid at that point, ρ is the fluid density, g is the acceleration due to gravity, h is the height of that point, and C is a constant), when the air velocity V increases, ρ remains unchanged, and H remains unchanged, then P decreases, creating a pressure difference with the left side of the air guide ring. In this way, air enters the fan blade flow channel more smoothly, improving the working efficiency of the fan.

[0031] Furthermore: The airfoil-shaped air guide ring not only increases the air volume of the fan but also improves the air pressure of the fan, enabling air to be better discharged outdoors. When the outdoor wind backflows severely, an air pressure opposite to the exhaust direction of the fan will be generated, causing the airflow inside the fan to backflow through the gap between the fan blades and the inner wall of the fan body. When the backflow airflow encounters the airfoil-shaped air guide ring, it needs to "climb uphill" and meet the air entering the fan. Due to the arc design of the airfoil-shaped air guide ring, the backflow airflow will rotate and turn back to be discharged outdoors again, effectively preventing the backflow of the airflow and ensuring the strong exhaust capacity of the fan.

[0032] Through the above design and working principle, the novel airfoil-shaped front air guide ring of the present invention can significantly improve the air exhaust volume and air pressure of the fan, optimize the airflow path, enhance the overall efficiency and performance of the fan, solve the problems of insufficient air volume, low air pressure, and backflow existing in the prior art, and provide a more efficient solution for cooling and ventilation in air conditioning equipment and household electrical appliances, so it can be widely promoted and used.

[0033] Obviously, the above embodiments are merely examples given for clear illustration and are not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all implementation manners here. And the obvious changes or modifications derived therefrom still fall within the protection scope of the claims of this utility model creation.

Claims

1. A front air guide ring for a duct fan, characterized in that: It comprises a first air guide ring (1), a second air guide ring (2) and a third air guide ring (3) extending in the air outlet direction, the diameter of the second air guide ring (2) being smaller than the diameters of the first air guide ring (1) and the second air guide ring (2), and the inner surfaces of the first air guide ring (1), the second air guide ring (2) and the third air guide ring (3) being connected in a circular arc transition to form an airfoil-shaped cross section protruding in the direction of the hole.

2. The front air guide ring for a duct fan according to claim 1, characterized in that: A circular trumpet-shaped air inlet area (4) with a larger outside and a smaller inside is formed between the first air guide ring (1) and the second air guide ring (2), and a circular trumpet-shaped air outlet area (5) with a larger outside and a smaller inside is formed between the second air guide ring (2) and the third air guide ring (3).

3. A front air guide ring for a duct fan according to claim 1 or 2, characterized in that: The outer cylindrical surfaces of the first air guide ring (1), the second air guide ring (2) and the third air guide ring (3) are in the shape of an inwardly concave annular groove, and a plurality of reinforcing ribs (6) are axially extended in the annular groove.

4. A front air guide ring for a duct fan according to claim 1 or 2, characterized in that: The maximum diameter of the first air guide ring (1) is greater than the diameter of the third air guide ring (3); after the air guide ring and the duct fan (7) are assembled, the first air guide ring (1) covers the air inlet end face of the duct fan (7), and the maximum diameter of the third air guide ring (3) is smaller than the inner diameter of the duct fan (7), so that the third air guide ring (3) is embedded in the inner wall of the duct fan (7).

5. A front air guide ring for a duct fan according to claim 1 or 2, characterized in that: The first air guide ring (1), the second air guide ring (2) and the third air guide ring (3) are integrally injection-molded from a plastic material.

Images