Volute and centrifugal fan comprising the same

Abstract

This invention provides a volute and a centrifugal fan containing it. The volute includes end caps at both axial ends, and an adjustment device perpendicular to the axial direction is installed on the end caps. The adjustment device is configured to adjust the outlet area of ​​the volute by blocking it according to the outlet resistance. By matching the outlet resistance with the outlet area, the adjustment device significantly improves the adaptability of the centrifugal fan: when the outlet resistance is high, the adjustment device increases the blocking area of ​​the outlet, reduces the actual outlet diameter, promotes a decrease in airflow velocity and an increase in pressure, and achieves efficient conversion of kinetic energy into pressure energy, thereby overcoming the exhaust bottleneck in high-resistance environments; while under low-resistance conditions, the adjustment device correspondingly reduces the blocking area and expands the outlet size to ensure smooth airflow at a larger flow rate, avoiding efficiency loss due to diameter limitations. This dynamic adjustment mechanism enables the centrifugal fan with this volute to maintain efficient operation in both high and low resistance scenarios.

Description

Technical Field

[0001] This utility model relates to the technical field of range hoods, and in particular to a volute and a centrifugal fan containing therein. Background Technology

[0002] In centrifugal fans used in range hoods, the design of the volute's outlet area is crucial to the fan's performance under different resistance conditions. During actual use, range hoods typically encounter two operating conditions: low resistance and high resistance. Low resistance usually occurs when there is less smoke and the duct is clear, requiring a larger outlet flow rate to quickly expel air. High resistance, on the other hand, may occur when the smoke concentration is high, the duct is filled with oil, or the filter is clogged, requiring the fan to expel air more effectively to overcome greater resistance.

[0003] In traditional design methods, the selection of the volute outlet area often requires a trade-off between low-resistance and high-resistance operating conditions. However, this compromise design struggles to simultaneously meet the optimal performance requirements of both conditions. If the volute design favors low-resistance operation, a larger outlet spacing is typically used to ensure sufficient outlet area, thereby achieving a larger outlet flow rate under low-resistance conditions. However, if the outlet resistance suddenly increases (e.g., due to filter clogging), the larger outlet spacing increases the backflow area, exacerbating backflow and intensifying internal flow turbulence. This not only leads to increased turbulent noise and mechanical vibration noise but also significantly reduces the fan's efficiency.

[0004] Conversely, if the volute design is geared towards high-resistance conditions, the outlet spacing is typically designed to be smaller to facilitate the conversion of kinetic energy into pressure energy in the airflow, thereby expelling the gas more effectively. However, under low-resistance conditions, a smaller outlet spacing can obstruct airflow, resulting in limited flow. Furthermore, the high-speed airflow blocked at the outlet can cause abnormal noise increases, further reducing the fan's efficiency.

[0005] Currently, to improve the practicality of centrifugal fans in range hoods, most volute designs attempt to find a compromise outlet area between high-resistance and low-resistance operating conditions. However, while this design addresses both conditions to some extent, it cannot achieve optimal performance in either condition, and may even lead to performance degradation in both. Utility Model Content

[0006] The technical problem to be solved by this utility model is to overcome the defect that the performance of centrifugal fans with compromised outlet area is reduced under both high resistance and low resistance conditions, and to provide a volute and a centrifugal fan containing the volute.

[0007] The present invention solves the above-mentioned technical problems through the following technical solution:

[0008] A volute for a centrifugal fan, the volute including end caps disposed at both ends along an axial direction, the end caps being equipped with an adjustment device perpendicular to the axial direction, the adjustment device being configured to adjust the air outlet area of ​​the volute in a blocking manner according to the magnitude of the air outlet resistance of the volute.

[0009] In this technical solution, the regulating device significantly improves the operating condition adaptability of the centrifugal fan by matching the outlet resistance with the outlet area: when the volute outlet resistance is high, the regulating device increases the obstruction area of ​​the outlet and reduces the actual outlet diameter, causing the airflow velocity to decrease and the pressure to increase, achieving efficient conversion of kinetic energy into pressure energy, thereby overcoming the exhaust bottleneck in high-resistance environments; while under low-resistance conditions, the regulating device correspondingly reduces the obstruction area and expands the outlet size to ensure that the airflow is discharged smoothly at a larger flow rate, avoiding efficiency loss due to diameter limitations. This dynamic regulating mechanism enables the centrifugal fan equipped with this volute to maintain efficient operation in both high and low resistance scenarios, effectively solving the technical problem of poor operating condition adaptability of traditional fans.

[0010] Meanwhile, since the outlet area can be adjusted according to the outlet resistance, it avoids the backflow phenomenon from being aggravated due to the excessive outlet area when the outlet resistance suddenly increases. It also avoids the airflow being obstructed due to the small outlet area when the outlet resistance decreases, thus reducing turbulence noise and mechanical vibration noise and improving the user experience.

[0011] The end cap of the volute is perpendicular to the axial direction of the volute. The adjustment device is located at the end cap, which can make full use of the low airflow resistance at the end cap. When the adjustment device is opened and closed, the aerodynamic resistance is low, which improves the response sensitivity and ease of operation of the adjustment device.

[0012] Preferably, the adjusting device includes a flap and a driving mechanism. The flap is rotatably connected to the end cover, and the driving mechanism is connected to the flap and is used to drive the flap to rotate so as to adjust the area of ​​the flap covering the air outlet.

[0013] In this technical solution, a specific structural form of the adjustment device is provided: the area of ​​the air outlet is adjusted by rotating the flap, and the flap is driven to rotate by a drive mechanism.

[0014] Preferably, the pivot of the flap is perpendicular to the axial direction.

[0015] In this technical solution, by setting the rotating shaft of the flap to be perpendicular to the axial direction of the volute, the position of the flap in the air outlet direction changes less when the flap rotates, and the resistance it experiences is more stable, thus improving the stability of the adjustment device.

[0016] Preferably, the flap is positioned at the edge of the air outlet along the air outlet direction.

[0017] In this technical solution, the resistance at the edge of the air outlet is low, and the flipping resistance at the edge of the flap is even smaller, making it easy to flip.

[0018] Preferably, the rotation angle of the flap does not exceed 45°.

[0019] In this technical solution, the rotational resistance is relatively small when the rotation angle of the flap does not exceed 45°.

[0020] Preferably, the flap extends to the wall of the volute in a direction perpendicular to the axial direction.

[0021] In this technical solution, the longer the flap extends in the direction perpendicular to the axial direction, the better the adjustment effect. Setting the flap to extend in the direction perpendicular to the axial direction to abut against the wall of the volute can achieve a better adjustment effect.

[0022] Preferably, the drive mechanism is located on the side of the end cover away from the air outlet.

[0023] In this technical solution, the drive mechanism is located on the side of the end cover away from the air outlet, and is not located inside the air outlet, so as to avoid the drive mechanism affecting the air outlet resistance.

[0024] A centrifugal fan includes a volute as described above, the volute further including at least one pressure sensor disposed near the regulating device, the pressure sensor being used to detect the resistance of the air outlet.

[0025] In this technical solution, by setting a pressure sensor to detect the resistance of the air outlet, it is possible to achieve real-time monitoring of the air outlet resistance, thereby realizing intelligent dynamic adjustment of the regulating device and significantly improving the working condition adaptability of the centrifugal fan.

[0026] Preferably, there are multiple pressure sensors, which are evenly arranged at the air outlet.

[0027] In this technical solution, setting up multiple sensors can more accurately and comprehensively detect the air outlet resistance, thereby making the adjustment of the regulating device more adaptable to the current working conditions.

[0028] Preferably, the centrifugal fan further includes a control unit, which is electrically connected to the pressure sensor and the drive mechanism, and is used to control the drive mechanism to rotate the flap based on the resistance of the air outlet detected by the pressure sensor.

[0029] The significant advantages of this invention are as follows: the regulating device significantly improves the adaptability of the centrifugal fan by matching the outlet resistance with the outlet area. When the outlet resistance of the volute is high, the regulating device increases the area of ​​obstruction at the outlet, reduces the actual outlet diameter, and promotes a decrease in airflow velocity and an increase in pressure, achieving efficient conversion of kinetic energy into pressure energy, thereby overcoming the exhaust bottleneck in high-resistance environments. Conversely, under low-resistance conditions, the regulating device correspondingly reduces the obstruction area and expands the outlet size, ensuring smooth airflow at a larger volume and avoiding efficiency losses due to diameter limitations. This dynamic regulating mechanism enables the centrifugal fan equipped with this volute to maintain efficient operation in both high and low resistance scenarios, effectively solving the technical problem of poor adaptability of traditional fans. Attached Figure Description

[0030] Figure 1 This is a three-dimensional structural diagram of the volute shell according to an embodiment of the present invention.

[0031] Figure 2 This is a cross-sectional structural diagram of the air outlet of the volute in an embodiment of the present invention when the shielding area is at its maximum.

[0032] Figure 3 This is a cross-sectional structural diagram of the air outlet of the volute in an embodiment of the present invention when the obstruction area is minimized.

[0033] Figure 4 This is a partial structural diagram of the volute shell according to an embodiment of the present invention.

[0034] Figure 5 This is a three-dimensional structural diagram of a flap according to an embodiment of the present invention.

[0035] 100 volcano

[0036] End cap 1

[0037] Air outlet 101

[0038] Connection slot 102

[0039] Adjustment device 2

[0040] Flip-board 21

[0041] Rectangular part 211

[0042] Arc-shaped part 212

[0043] Connecting rod 22

[0044] Axial L

[0045] Air outlet direction N Detailed Implementation

[0046] The present invention will be described more clearly and completely below with reference to the accompanying drawings, using a preferred embodiment.

[0047] This embodiment provides a centrifugal fan for use in a range hood. The centrifugal fan includes a volute 100, such as... Figures 1-4 As shown, the volute 100 includes end caps 1 at both ends along the axial direction L. An adjustment device 2 perpendicular to the axial direction L is mounted on the end caps 1. The adjustment device 2 is configured to adjust the outlet area of ​​the volute 100 by blocking it according to the magnitude of the outlet resistance. By matching the outlet resistance with the outlet area, the adjustment device 2 significantly improves the adaptability of the centrifugal fan: when the outlet resistance of the volute 100 is high, the adjustment device 2 increases the blocking area of ​​the outlet, reduces the actual outlet diameter, causing the airflow velocity to decrease and the pressure to increase, achieving efficient conversion of kinetic energy into pressure energy, thereby overcoming the exhaust bottleneck in high-resistance environments; while under low-resistance conditions, the adjustment device 2 correspondingly reduces the blocking area and expands the outlet size, ensuring smooth airflow at a larger volume, avoiding efficiency loss due to diameter limitations. This dynamic adjustment mechanism enables the centrifugal fan equipped with this volute 100 to maintain efficient operation in both high and low resistance scenarios, effectively solving the technical problem of poor adaptability of traditional fans. The inclusion of the aforementioned volute 100 in the range hood can improve its operating efficiency.

[0048] Meanwhile, since the outlet area can be adjusted according to the outlet resistance, it avoids the backflow phenomenon from being aggravated due to the excessive outlet area when the outlet resistance suddenly increases. It also avoids the airflow being obstructed due to the small outlet area when the outlet resistance decreases, thus reducing turbulence noise and mechanical vibration noise and improving the user experience.

[0049] The end cap 1 of the volute 100 is perpendicular to the axial direction L of the volute 100. The adjustment device 2 is set at the end cap 1. The characteristic of low airflow resistance at the end cap 1 can be fully utilized. When the adjustment device 2 is opened and closed, the aerodynamic resistance is low, which improves the response sensitivity and ease of operation of the adjustment device 2.

[0050] In this embodiment, there is one adjusting device 2, which is installed on one of the end caps 1 of the volute 100.

[0051] Of course, in other embodiments, the number of adjustment devices 2 can also be two, and the two adjustment devices 2 can be respectively set on the two end caps 1, which will not be described in detail here.

[0052] In this embodiment, the adjustment device 2 adjusts the occlusion area of ​​the air outlet by rotation. The adjustment device 2 includes a flap 21 and a drive mechanism. The flap 21 is rotatably connected to the end cover 1, and the drive mechanism is connected to the flap 21 and is used to drive the flap 21 to rotate so as to adjust the occlusion area of ​​the flap 21 on the air outlet.

[0053] Of course, in other embodiments, the obstruction area of ​​the air outlet can also be adjusted by translation. For example, the air outlet can be obstructed by setting a flat plate structure perpendicular to the air outlet direction N on the end cover 1, and the obstruction area of ​​the air outlet can be adjusted by driving the flat plate to move inward or outward of the end cover 1.

[0054] Specifically, in this embodiment, the rotation axis of the flap 21 is perpendicular to the axial direction L. By setting the rotation axis of the flap 21 to be perpendicular to the axial direction L of the volute 100, the position of the flap 21 in the direction perpendicular to the axial direction L remains unchanged when the flap 21 rotates, and the position of the flap 21 in the air outlet direction N changes little, resulting in more stable and uniform resistance and improving the stability of the adjustment device 2.

[0055] Meanwhile, the flap 21 is positioned at the edge of the air outlet along the air outlet direction N. Based on the airflow characteristics of the air outlet, the resistance at the edge of the air outlet is lower, resulting in even less resistance to the flap 21's rotation at the edge, making it easier to rotate.

[0056] In this embodiment, the flap 21 rotates from a position where it does not obstruct the air outlet to a position where it maximizes the area of ​​obstruction of the air outlet, and the rotation angle of the flap 21 does not exceed 45°. According to the airflow distribution characteristics of the air outlet, the rotation resistance is relatively small when the rotation angle of the flap 21 does not exceed 45°.

[0057] Specifically in this embodiment, such as Figures 2-5 As shown, the cross-section of the flap 21 is a fan-shaped structure, as... Figure 5 As shown, the flap 21 includes an arc-shaped portion 212 and two rectangular portions 211 respectively connected to both ends of the arc-shaped portion 212. The ends of the two rectangular portions 211 away from the arc-shaped portion 212 are not connected. Figure 4 As shown, the end cap 1 is provided with a connecting groove 102 extending through it along the axial direction L. An arc-shaped portion 212 is inserted into the connecting groove 102, such that the wall surface of the end cap 1 is located between two rectangular portions 211. Figure 2 As shown, when the rectangular portion 211 on the outer side of the flap 21 is in contact with the end cover 1, the flap 21 reaches its maximum blocking area on the air outlet. Figure 3As shown, when the rectangular portion 211 on the inner side of the flap 21 is in contact with the end cover 1, the flap 21 does not obstruct the air outlet. The included angle between the two rectangular portions 211 is 30°. That is, in this embodiment, the maximum rotation angle of the flap 21 is 30°. The connection between the flap 21 and the volute 100 is achieved through the cooperation of the connecting groove and the flap 21, without the need for additional connecting structures, making the structure of the adjustment device 2 simpler and more reliable.

[0058] In addition, the fan-shaped structure of flap 21 has great stability. Under the dynamic action of the airflow at the air outlet, it has high structural stability and the structure of flap 21 is not easily damaged.

[0059] Of course, in other embodiments, the flap 21 can also be configured in other structural forms, such as a flat plate that is hinged to the end cover 1, so as to achieve the purpose of the flap 21 being rotatable relative to the end cover 1, which will not be elaborated here.

[0060] The longer the flap 21 extends in the direction perpendicular to the axial direction L, the better the adjustment effect on the air outlet area. Therefore, in this embodiment, the flap 21 extends in the direction perpendicular to the axial direction L to abut against the wall of the volute, thereby achieving a better adjustment effect.

[0061] In this embodiment, the drive mechanism is located on the side of the end cover 1 away from the air outlet, and is not located inside the air outlet, so as to avoid the drive mechanism affecting the air outlet resistance.

[0062] Specifically, in this embodiment, the driving mechanism is a motor (not shown in the figure). Figure 2 and Figure 3 As shown, the motor is connected to the flap 21 via the connecting rod 22 to drive the flap 21 to rotate.

[0063] In this embodiment, a pressure sensor is also installed inside the volute 100. The pressure sensor is used to detect the resistance of the air outlet and is located close to the regulating device. By using a pressure sensor to detect the resistance of the air outlet, real-time monitoring of the air outlet resistance can be achieved, thereby enabling intelligent dynamic adjustment of the regulating device 2 and significantly improving the adaptability of the centrifugal fan to different operating conditions.

[0064] Specifically, there are four pressure sensors (not shown in the figure), which are evenly distributed at the air outlet, specifically at the four corners of the air outlet. Using four sensors allows for more accurate and comprehensive detection of the air outlet resistance, thus enabling the adjustment device 2 to better adapt to the current operating conditions.

[0065] Of course, in other embodiments, the number of pressure sensors can also be other values. For example, there can be one, two, or more pressure sensors. When there is only one pressure sensor, it is placed close to the regulating device 2, which is more able to reflect the resistance near the regulating device 2. When there are multiple pressure sensors, they are evenly arranged at the air outlet.

[0066] In this embodiment, the centrifugal fan also includes a control unit, which is electrically connected to a pressure sensor and a drive mechanism. The control unit is used to control the drive mechanism to rotate the flap based on the resistance of the air outlet 101 detected by the pressure sensor, thereby realizing intelligent adjustment of the flap 21.

[0067] While specific embodiments of this utility model have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of this utility model is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of this utility model, but all such changes and modifications fall within the scope of protection of this utility model.

Claims

1. A volute casing for a centrifugal fan, the volute casing comprising end caps disposed at both axial ends, characterized in that, An adjustment device perpendicular to the axis is installed on the end cover. The adjustment device is configured to adjust the air outlet area of ​​the volute in a blocking manner according to the air outlet resistance of the volute.

2. The volute as described in claim 1, characterized in that, The adjustment device includes a flap and a drive mechanism. The flap is rotatably connected to the end cover, and the drive mechanism is connected to the flap and is used to drive the flap to rotate so as to adjust the area of ​​the flap that it blocks from the air outlet.

3. The volute as described in claim 2, characterized in that, The hinge of the flap is perpendicular to the axial direction.

4. The volute as described in claim 2, characterized in that, The flap is positioned at the edge of the air outlet along the air outlet direction.

5. The volute as described in claim 2, characterized in that, The rotation angle of the flap does not exceed 45°.

6. The volute as described in claim 2, characterized in that, The flap extends in a direction perpendicular to the axial direction to abut against the wall of the volute.

7. The volute as described in claim 2, characterized in that, The drive mechanism is located on the side of the end cover away from the air outlet.

8. A centrifugal fan, characterized in that, The centrifugal fan includes a volute as described in any one of claims 2-7, and the centrifugal fan further includes at least one pressure sensor disposed near the regulating device, the pressure sensor being used to detect the resistance of the air outlet.

9. The centrifugal fan as described in claim 8, characterized in that, The pressure sensors are multiple, and the multiple pressure sensors are evenly arranged at the air outlet.

10. The centrifugal fan as described in claim 8, characterized in that, The centrifugal fan also includes a control unit, which is electrically connected to the pressure sensor and the drive mechanism, and is used to control the drive mechanism to rotate the flap based on the resistance of the air outlet detected by the pressure sensor.

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