Single-stage double-suction centrifugal fan

Abstract

The application discloses a single-stage double-suction centrifugal ventilator and relates to the technical field of ventilating and cleaning equipment. The single-stage double-suction centrifugal ventilator comprises an impeller, a shell and a circular ring shell piece. The impeller comprises a connecting frame and a plurality of fan blades arranged on the two sides of the connecting frame. The impeller rotates around the shaft under the driving of a driving device. The shell is composed of two identical cap-shaped shell pieces. The two cap-shaped shell pieces are oppositely arranged with a space and are connected into an integrated whole at the lower part and are provided with a flat base for installation. A ring-shaped protrusion is arranged on the edge of the two cap-shaped shell pieces towards the opposite inner side. The circular ring shell piece is arranged between the two cap-shaped shell pieces. The two ends of the circular ring shell piece are embedded and installed with the ring-shaped protrusions of the cap-shaped shell pieces. Under the limitation of the ring-shaped protrusions at the two ends, the circular ring shell piece can rotate freely around the shaft. The shell wall of the circular ring shell piece extends outward to form an air outlet parallel to the tangential direction of the circular ring shell piece. The air outlet can rotate together with the circular ring shell piece to adjust the angle of the air outlet and meet the installation requirement.

Description

Technical Field

[0001] This invention relates to the field of ventilation and cleaning equipment technology, and more specifically, to a single-stage double-suction centrifugal fan. Background Technology

[0002] Centrifugal fans are widely used in ventilation equipment for ventilation in factories, tunnels, mines and other places. When the blades of a centrifugal fan rotate, the air drawn in from the inlet undergoes centrifugal motion under the push of the blades, is guided by the volute, and is discharged from the outlet, thus achieving the purpose of ventilation and exhaust.

[0003] Currently, most existing fan outlets are fixed designs. Once the fan is fixed to the frame, the position and direction of the outlet are also fixed, making it impossible to flexibly adjust the airflow angle. This often requires the installation of additional airflow deflectors or ductwork to redirect the airflow. Chinese patent CN202022791512.8 provides a design with detachable frame mounting feet to facilitate easy adjustment of the outlet direction. However, this design becomes inconvenient in situations with limited space or where frequent adjustments to the airflow direction are needed. Furthermore, the adjustable direction is limited to a fixed angle, which still presents significant limitations.

[0004] In addition, after prolonged use, dust and dirt inevitably accumulate on the fan blades and internal casing, carried in by the airflow. These deposits affect airflow within the duct, reducing the fan's suction and exhaust efficiency and increasing energy consumption, necessitating regular cleaning. During cleaning, only a rough cleaning can be performed through the fan's inlet and outlet. Due to the curved fan blades and tight assembly, dirt and accumulated dust on the circular internal casing still require disassembly and cleaning, affecting the fan's operation. Summary of the Invention

[0005] To solve the aforementioned technical problems, this invention provides a single-stage double-suction centrifugal fan that improves the outlet structure of the fan, enabling convenient and adjustable air outlet angle after frame installation, and reducing the difficulty of cleaning the inside of the fan, allowing for cleaning without disassembling the machine.

[0006] The present invention provides a single-stage double-suction centrifugal fan, comprising an impeller, a housing, and an annular shell plate.

[0007] The impeller includes a connecting frame and fan blades. Several fan blades are arranged on both sides of the connecting frame, with each side's blades evenly distributed and fixedly connected to the connecting frame's axis. The fan blades enclose the axis on both sides of the connecting frame to form air intakes, and the fan blades form multiple air exhaust ports on the outer periphery of the connecting frame. Driven by a drive unit, the impeller rotates around its axis inside the casing.

[0008] The shell consists of two identical cap-shaped shell plates, which are spaced apart and opposite to each other, and are joined together at the bottom to form a flat base for mounting. A ring of protrusions is formed along the edges of the two cap-shaped shell plates, pointing inwards towards each other.

[0009] A circular shell is positioned between two cap-shaped shells. The two ends of the circular shell are embedded in the annular protrusions of the cap-shaped shells, allowing it to rotate freely around the axial direction under the constraint of the annular protrusions at both ends. The shell wall of the circular shell extends outward to form an air outlet parallel to the tangential direction of the circular shell, and the air outlet can rotate with the circular shell.

[0010] As a further improvement of the present invention, a cleaning structure is also included, wherein a cleaning port is vertically opened at the lower part of the cap-shaped shell on one side, the cleaning port is located above the annular shell embedded in the bottom cap-shaped shell, and a removable baffle is provided at the cleaning port for sealing.

[0011] As a further improvement of the present invention, the cleaning structure also includes a dust collection port, which is formed on the shell wall of the annular shell and has a dense mesh-like structure. The dust collection port is sealed by an arc-shaped plate that slides in close contact.

[0012] As a further improvement of the present invention, a slot is provided in the middle position below the flat base, and a dust collection hopper is installed in the slot. When the dust discharge port rotates to the bottom with the annular shell, it is located directly above the dust collection hopper.

[0013] As a further improvement of the present invention, the two cap-shaped shell plates of the housing are fixedly connected by several detachably connected crossbars.

[0014] As a further improvement of the present invention, the left and right ends of the air outlet protrude to both sides, forming two arc-shaped groove structures. The protruding ends on both sides fit against the outer edges of the left and right cap-shaped shell pieces, forming an envelope around the annular protrusions of the cap-shaped shell pieces. Bolts facing the groove structures are installed on the protruding parts. When the bolts are screwed in, they abut against and fix the cap-shaped shell pieces that are enveloped in the arc-shaped groove structures.

[0015] As a further improvement of the present invention, the blade tip is inclined at the air intake, forming an angle with the axis of the connecting frame. As the blade tip extends towards the exhaust port, it tilts and deflects as a whole, with the blade tail parallel to the axis of the connecting frame, and the overall blade shape is a curved and swept-back convex arc shape.

[0016] As a further improvement of the present invention, the arrangement of the fan blades on both sides of the impeller is symmetrical or asymmetrical. When the structure is asymmetrical, the fan blades on the left and right sides of the connecting frame are arranged at intervals, and the location of a single fan blade on one side corresponds to the interval position of two fan blades on the other side.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0018] This invention employs an air outlet design that rotates with the annular shell, allowing for stepless adjustment of the air outlet angle according to specific scenario needs. The angle is fixed using bolts to meet the installation requirements of different equipment and locations.

[0019] Meanwhile, taking advantage of the rotatable feature of the annular shell, cleaning tools can be inserted through the cleaning port of the cap-shaped shell, and the annular shell can be rotated to clean the inner circular shell wall. The accumulated dust and dirt are discharged from the dust outlet of the movable switch below, achieving cleaning without disassembling the machine. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0021] Figure 2 This is a schematic diagram of the symmetrical impeller structure of the present invention;

[0022] Figure 3 This is a schematic diagram of the fan blade of the present invention;

[0023] Figure 4 This is a schematic diagram of the structure of the cap-shaped shell plate on the shell of the present invention;

[0024] Figure 5 This is a schematic diagram of the annular shell structure of the present invention;

[0025] Figure 6 This is a schematic diagram of the dust collection port below the annular shell sheet of the present invention;

[0026] Figure 7 This is a schematic diagram of the internal cleaning structure of the cap-shaped shell sheet after half-section of one side of the present invention.

[0027] Figure 8 This is a schematic diagram of the asymmetric impeller structure of the present invention;

[0028] Explanation of the labels in the diagram:

[0029] 1. Impeller; 2. Shell; 3. Circular shell plate; 4. Cleaning structure; 101. Connecting frame; 102. Fan blade; 103. Air intake; 104. Air exhaust; 201. Cap-shaped shell plate; 202. Flat base; 301. Air outlet; 401. Cleaning port; 402. Dust collection port; 403. Dust collection hopper. Detailed Implementation

[0030] Specific Implementation Example 1: Please refer to the appendix Figures 1-8 A single-stage double-suction centrifugal fan includes an impeller 1, a housing 2, and an annular shell 3.

[0031] The housing 2 consists of two identical cap-shaped shell plates 201. Each cap-shaped shell plate 201 is an annular structure with a central opening. The inner annular wall extends and converges along the axis of the ring, forming an open, conical protrusion. The two cap-shaped shell plates 201 are spaced apart with their conical protrusions facing away from each other. Their lower parts are connected as a single unit and have a rectangular flat base 202 for mounting. A ring of annular protrusions is formed along the edges of the two cap-shaped shell plates 201, pointing inwards towards each other. The two cap-shaped shell plates 201 of the housing 2 are fixedly connected by several detachable crossbars.

[0032] The impeller 1 includes a connecting frame 101, fan blades 102, an air intake 103, and an air exhaust 104. The connecting frame 101 is a disc-shaped part with a boss at the center of each side serving as a rotating shaft. A through hole and a keyway are provided at the center of the shaft for connecting the output shaft of the motor. Fan blades 102 are provided on both sides of the connecting frame 101, with 6 fan blades 102 symmetrically arranged on each side. The fan blades 102 are evenly arranged around the boss at the center of the connecting frame 101 and are fixedly connected to it. At the position of the fan blade 102 near the central boss of the connecting frame 101, each pair of adjacent fan blades 102 forms an independent air intake 103. When the impeller 1 rotates, airflow enters through the air intake 103. At the position of the fan blade 102 near the outer edge of the connecting frame 101, each pair of adjacent fan blades 102 forms an independent air exhaust 104. When the impeller 1 rotates, the airflow entering through the air intake 103 is centrifugally discharged through the air exhaust 104. Specifically, the blade tip of the fan blade 102 is inclined at the air intake 103, forming an angle with the axis of the connecting frame 101. As the blade tip extends towards the exhaust 104, it tilts and deflects, with the blade tail parallel to the axis of the connecting frame 101, and the overall blade shape is a curved, swept-back convex arc shape. The impeller 1 is fitted inside the housing 2 and rotates around the axis under the drive of the motor's output shaft.

[0033] The annular shell 3 is a ring-shaped part, and its outer diameter is equal to the inner diameter of the annular protrusion of the shell 2. The annular shell 3 is disposed between two cap-shaped shells 201, and its two ends are embedded in the annular protrusions of the cap-shaped shells 201. Under the constraint of the annular protrusions at both ends, it can rotate freely around the axial direction. An air outlet 301 is formed on the shell of the annular shell 3. The air outlet 301 is parallel to the tangent of the annular shell 3 and rotates freely around the axial direction with the annular shell 3. The left and right ends of the air outlet 301 protrude to both sides, forming two arc-shaped groove structures. The protruding ends on both sides fit with the outer edges of the left and right cap-shaped shells 201, forming an envelope around the annular protrusions of the cap-shaped shells 201. The protruding part is fitted with a bolt facing the groove structure. When the bolt is screwed in, it abuts against the annular protrusion of the cap-shaped shell 201 that is enclosed in the arc-shaped groove structure, thereby achieving a fixed connection between the annular shell 3 and the cap-shaped shell 201.

[0034] Working principle:

[0035] The fan is fixed to the installation position by the flat base 202. If the air outlet direction needs to be adjusted, the connecting crossbar between the two cap-shaped shell pieces 201 of the housing 2 needs to be removed first, and the bolts on the protruding part of the air outlet 301 need to be loosened. Then, rotate the annular shell piece 3 to rotate the air outlet 301 to the target angle. Finally, tighten the bolts on the protruding part of the air outlet 301 to fix the annular shell piece 3 to the housing 2, and install the connecting crossbar at a position that does not interfere with the air outlet 301 to connect the left and right cap-shaped shell pieces 201.

[0036] Specific Embodiment Two: Based on Specific Embodiment One, a cleaning structure is also included. The cleaning structure includes a cleaning port 401, a dust collection port 402, and a dust collection hopper 403. The cleaning port 401 is located at the lower part of a cap-shaped shell 201 on one side, vertically penetrating the shell wall of the cap-shaped shell 201. The cleaning port 401 is located above the annular shell 3 embedded in the bottom cap-shaped shell 201. When not in use, the cleaning port 401 is sealed with a removable baffle. The dust collection port 402 is located on the shell wall of the annular shell 3, forming a dense mesh-like structure. When not in use, the dust collection port 402 is sealed with a sliding arc-shaped plate. A slot is provided on the flat base 202 directly below the cleaning port 401, and the dust collection hopper 403 is embedded in the slot. When the dust collection port 402 rotates to the lower position with the annular shell 3, it is directly above the dust collection hopper 403.

[0037] During cleaning, open the sealing baffle of cleaning port 401 and the sliding arc plate on dust collection port 402, as follows: Figure 7 As shown, a cleaning brush is inserted into the cleaning port 401. As in the first embodiment, the ring-shaped shell 3 is loosened. While rotating the ring-shaped shell 3, the inner shell wall is cleaned with the brush, and the dust collected is discharged from the dust outlet 402 into the dust collection hopper 403.

[0038] Specific Embodiment Three: Based on the above embodiments, the blade arrangement of impeller 1 is changed, such as... Figure 8 As shown, the arrangement of the fan blades 102 on both sides of the impeller 1 is asymmetrical. The fan blades 102 on the left and right sides of the connecting frame 101 are arranged at intervals, with the location of a single fan blade 102 on one side corresponding to the interval between two fan blades 102 on the other side. The asymmetrical impeller design can reduce the pulse pressure of the airflow, making the discharged airflow continuous and uniform. Furthermore, the staggered airflow channel formed by the staggered fan blades 102 can reduce the torsional vibration of the impeller 1, balance the airflow forces on both sides, and make the rotation more stable.

[0039] The above description is only a preferred embodiment of the present invention and is not intended to limit the scope of the invention. All variations, modifications, and substitutions within the spirit and principle of this design are within the protection scope of the present invention.

Claims

1. A single-stage double-suction centrifugal fan, characterized in that: It includes an impeller (1), a housing (2), an annular shell plate (3), and a cleaning structure (4); The impeller (1) includes a connecting frame (101) and fan blades (102). Several fan blades (102) are respectively arranged on both sides of the connecting frame (101). The fan blades (102) on each side are evenly arranged around the axis of the connecting frame (101) and fixedly connected to it. The fan blades (102) form air intakes (103) at the axis positions on both sides of the connecting frame (101), and the fan blades (102) form multiple air exhaust ports (104) at the outer periphery of the connecting frame (101). The impeller (1) rotates around the axis inside the housing (2) under the drive of the drive device. The shell (2) is composed of two identical cap-shaped shell pieces (201), which are arranged opposite each other at a distance and are connected at the bottom to form a whole and have a flat base (202) for installation; a ring of protrusions is formed on the edges of the two cap-shaped shell pieces (201) towards the opposite inner side; A circular shell plate (3) is disposed between two cap-shaped shell plates (201). The two ends of the circular shell plate (3) are embedded in the annular protrusions of the cap-shaped shell plate (201). Under the restriction of the annular protrusions at both ends, it can rotate freely around the axis. The shell wall of the circular shell plate (3) extends outward to form an air outlet (301) parallel to the tangent of the circular shell plate (3). The air outlet (301) can rotate with the circular shell plate (3). The cleaning structure (4) includes a cleaning port (401), a dust collection port (402), and a dust collection hopper (403). A cleaning port (401) is vertically opened at the lower part of a cap-shaped shell (201) on one side. The cleaning port (401) is located above the annular shell (3) embedded in the bottom cap-shaped shell (201). A removable baffle is provided at the cleaning port (401) for sealing. The dust collection port (402) is opened on the shell wall of the annular shell (3) and has a dense mesh-like structure. The dust collection port (402) is equipped with a sliding arc-shaped plate for feeding. The plate base (202) is sealed; a slot is provided in the middle of the plate base (202), and a dust collection hopper (403) is installed in the slot. When the dust collection port (402) rotates to the bottom with the annular shell (3), it is directly above the dust collection hopper (403). When cleaning, a cleaning brush is inserted into the cleaning port (401), the annular shell (3) is loosened, and the inner shell wall is cleaned with the brush while rotating the annular shell (3). The dust collected is discharged from the dust collection port (402) into the dust collection hopper (403).

2. The single-stage double-suction centrifugal fan according to claim 1, characterized in that: The two cap-shaped shell plates (201) of the shell (2) are fixedly connected by several detachable crossbars.

3. A single-stage double-suction centrifugal fan according to claim 1, characterized in that: The left and right ends of the air outlet (301) protrude to the sides respectively, forming two arc-shaped groove structures. The protruding ends on both sides fit with the outer edges of the two cap-shaped shells (201) and envelop the annular protrusion of the cap-shaped shells (201). The protruding parts are equipped with bolts facing the groove structure. When the bolts are screwed in, they abut against and are fixed to the cap-shaped shells (201) enveloping the arc-shaped groove structure.

4. A single-stage double-suction centrifugal fan according to claim 1, characterized in that: The blade tip of the fan blade (102) is inclined at the air intake (103) and forms an angle with the axis of the connecting frame (101); as the blade tip extends towards the exhaust port (104), it tilts and deflects as a whole, and the blade tail is parallel to the axis of the connecting frame (101), and the overall blade shape is a curved and swept convex arc shape.

5. A single-stage double-suction centrifugal fan according to claim 4, characterized in that: The arrangement of the fan blades (102) on both sides of the impeller (1) is symmetrical or asymmetrical. When it is asymmetrical, the fan blades (102) on the left and right sides of the connecting frame (101) are arranged at intervals, and the location of a single fan blade (102) on one side corresponds to the interval position of the two fan blades (102) on the other side.

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