Single-stage double-suction type centrifugal fan

Abstract

The invention discloses a single-stage double-suction type centrifugal fan, which relates to the technical field of ventilation cleaning equipment, and comprises an impeller, a shell and a ring-shaped shell piece, the impeller comprises a connecting frame and fan blades, and the fan blades are arranged on the two sides of the connecting frame respectively. The impeller is driven by the driving device to rotate around the axis in the shell; the shell is composed of two identical cap-shaped shell pieces, the two cap-shaped shell pieces are oppositely arranged in a spaced mode, the lower portions of the two cap-shaped shell pieces are connected into a whole, and a flat-plate-shaped base used for installation is manufactured on the lower portions of the two cap-shaped shell pieces. The edges of the two cap-shaped shell pieces are provided with a circle of annular protrusions towards the opposite inner sides. The annular shell piece is arranged between the two cap-shaped shell pieces, the two ends of the annular shell piece and the annular protrusions of the cap-shaped shell pieces are installed in an embedded mode, and the annular shell piece can freely rotate in the axial direction under the limitation of the annular protrusions at the two ends. The shell wall of the annular shell piece extends outwards to form an air outlet parallel to the tangential direction of the annular shell piece, the air outlet and the annular shell piece can rotate together, the air outlet angle is adjusted, and the installation requirement is met.

Description

Technical Field

[0001] The present invention relates to the technical field of ventilation and cleaning equipment, and more specifically to a single-stage double-suction centrifugal fan. Background Art

[0002] Centrifugal fans are widely used in ventilation equipment to ventilate factories, tunnels, mines, etc. When the blades of the centrifugal fan rotate, the inter-blade gas sucked in from the air inlet moves centrifugally under the push of the blades, guided by the volute, and discharged from the air outlet, achieving the purpose of ventilation and exhaust of the fan.

[0003] At present, most of the existing fan outlets are fixed designs. When the fan is fixed to the rack, the position and direction of the outlet are also fixed, and the outlet angle cannot be flexibly adjusted. It is often necessary to install additional drainage joints or air guide pipes to deflect the air. In the published Chinese patent CN202022791512.8, a detachable rack mounting foot design is provided to achieve easy adjustment of the outlet direction. However, when facing some installation locations with narrow space or scenes where the outlet direction needs to be adjusted frequently, it will cause inconvenience in use and installation. In addition, the direction that can be adjusted is a fixed angle, which still has great limitations.

[0004] In addition, after a long period of use, dust and dirt carried by the airflow will inevitably accumulate on the fan blades and the inner shell wall. These attachments will affect the flow of air in the air duct, reduce the suction and exhaust efficiency of the fan, increase energy consumption, and need to be cleaned regularly. When cleaning, only a rough cleaning can be performed through the fan inlet and outlet. Due to the curved fan blades and compact assembly, the dirt and dust on the circular inner shell wall still need to be disassembled and cleaned, which affects the start-up of the fan. Summary of the invention

[0005] In order to solve the above-mentioned technical problems, the present invention provides a single-stage double-suction centrifugal fan, improves the air outlet structure of the fan, and realizes that the air outlet angle of the air outlet is conveniently adjustable after the frame is installed, and reduces the difficulty of cleaning the inside of the fan, so that cleaning can be achieved without disassembling the machine.

[0006] The single-stage double-suction centrifugal fan of the present invention comprises an impeller, a casing and an annular shell.

[0007] The impeller includes a connecting frame and blades. A plurality of blades are arranged on both sides of the connecting frame. The blades on each side are evenly arranged around the axis of the connecting frame and fixedly connected thereto. The blades wrap around the axis on both sides of the connecting frame to form an air intake, and the blades form multiple air outlets at the periphery of the connecting frame. Driven by the driving device, the impeller rotates around the axis inside the housing.

[0008] The shell body is composed of two identical cap-shaped shell pieces, which are arranged opposite to each other at intervals, connected into one piece at the bottom and provided with a flat plate-shaped base for installation. A circle of annular protrusions are provided at the edges of the two cap-shaped shell pieces facing the opposite inner sides.

[0009] The annular shell is arranged between two cap-shaped shells, and the two ends of the annular shell are embedded and installed with the annular protrusions of the cap-shaped shell. Under the restriction of the annular protrusions at both ends, it can rotate freely around the axis. The shell wall of the annular shell extends outward to form an air outlet parallel to the tangent direction of the annular shell, and the air outlet can rotate with the annular shell.

[0010] As a further improvement of the present invention, it also includes a cleaning structure, in which 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 further comprises an ash drop opening, which is opened on the shell wall of the annular shell sheet and presents a dense mesh structure. The ash drop opening is provided with a sliding arc plate for sealing.

[0012] As a further improvement of the present invention, a slot is provided at the middle position below the flat base, an ash collecting hopper is embedded in the slot, and the ash outlet is located directly above the ash collecting hopper when the annular shell rotates to the bottom.

[0013] As a further improvement of the present invention, the two cap-shaped shells of the housing are fixedly connected by a plurality of detachably connected cross bars.

[0014] As a further improvement of the present invention, the left and right ends of the air outlet protrude to both sides respectively, forming two arc-shaped groove structures, and the protruding ends on both sides are in contact with the outer edges of the left and right cap-shaped shell pieces, forming an envelope for the annular protrusion of the cap-shaped shell piece. The protruding part is installed with a bolt facing the groove structure, and when the bolt is screwed in, it abuts and fixes the cap-shaped shell piece part enclosed in the arc-shaped groove structure.

[0015] As a further improvement of the present invention, the blade tip of the fan blade is tilted at the air inlet, forming an angle with the axis of the connecting frame. In the process of extending to the blade tail at the air outlet, the blade tip is tilted and deflected as a whole, the blade tail is parallel to the axis of the connecting frame, and the overall blade shape is a curved and swept convex arc shape.

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

[0017] Compared with the prior art, the present invention has the following beneficial effects: The present invention adopts an air outlet design that rotates with the annular shell, so that the angle of the air outlet can be infinitely adjusted according to the needs of specific scenes, and the angle can be fixed by bolts to meet the installation requirements of different equipment and places.

[0018] At the same time, by utilizing the rotatable feature of the annular shell, a cleaning tool can be inserted through the cleaning opening of the cap-shaped shell, and the annular shell can be rotated to clean the circular inner shell wall, and the accumulated dust and dirt can be discharged from the dust outlet of the movable switch below, thereby achieving cleaning without disassembling the machine. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 It is a schematic diagram of the symmetrical impeller structure of the present invention; Figure 3 It is a schematic diagram of a fan blade of the present invention; Figure 4 It is a structural schematic diagram of a cap-shaped shell piece on a housing of the present invention; Figure 5 It is a schematic diagram of the ring-shaped shell structure of the present invention; Figure 6 It is a schematic diagram of the ash outlet below the annular shell sheet of the present invention; Figure 7 It is a schematic diagram of the internal cleaning structure of a cap-shaped shell sheet on one side of the present invention after half-cut; Figure 8 It is a schematic diagram of the asymmetric impeller structure of the present invention; Description of the numbers in the figure: 1. Impeller; 2. Shell; 3. Ring-shaped shell; 4. Cleaning structure; 101. Connecting frame; 102. Fan blades; 103. Air inlet; 104. Air outlet; 201. Cap-shaped shell; 202. Flat base; 301. Air outlet; 401. Cleaning port; 402. Ash outlet; 403. Ash collecting hopper. DETAILED DESCRIPTION

[0020] Specific embodiment 1: Please refer to the attached Figure 1-Figure 8 A single-stage double-suction centrifugal fan comprises an impeller 1, a casing 2 and an annular shell 3.

[0021] The housing 2 is composed of two identical cap-shaped shell pieces 201. Each cap-shaped shell piece 201 is an annular structure with a central opening. The inner annular wall surface extends and closes in the direction of the ring axis, forming an open conical protrusion. The two cap-shaped shell pieces 201 are arranged at intervals in the direction opposite to the conical protrusion. The lower parts of the two cap-shaped shell pieces 201 are connected as a whole and are provided with a rectangular flat base 202 for installation. The edges of the two cap-shaped shell pieces 201 are provided with a circle of annular protrusions facing the opposite inner sides. The two cap-shaped shell pieces 201 of the housing 2 are fixedly connected by a plurality of detachable cross bars.

[0022] The impeller 1 includes a connecting frame 101, blades 102, an air inlet 103 and an air outlet 104. The connecting frame 101 is a round pancake-shaped part, with a boss as a rotating shaft at the axis of both sides, a through hole at the axis, and a keyway for connecting the output shaft of the motor. Blades 102 are arranged on both sides of the connecting frame 101, and 6 blades 102 are symmetrically arranged on each side. The blades 102 are evenly arranged around the boss at the axis of the connecting frame 101 and fixedly connected thereto. At the position where the fan blade 102 is close to the axial boss of the connecting frame 101, an independent air inlet 103 is formed between two adjacent fan blades 102. When the impeller 1 rotates, the air flow enters from the air inlet 103; at the position where the fan blade 102 is close to the outer edge of the connecting frame 101, an independent air outlet 104 is formed between two adjacent fan blades 102. When the impeller 1 rotates, the air flow entering from the air inlet 103 is centrifugally discharged from the air outlet 104. In particular, the blade end of the fan blade 102 is tilted at the air inlet 103, forming an angle with the axis of the connecting ring frame 101. In the process of extending to the tail of the blade at the air outlet 104, the blade end is tilted and deflected 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. The impeller 1 is mounted inside the housing 2, and driven by the output shaft of the motor, it performs a rotational motion around the axis.

[0023] The annular shell sheet 3 is an annular part, and its annular outer diameter is equal to the inner diameter of the annular protrusion of the shell body 2. The annular shell sheet 3 is arranged between two cap-shaped shell sheets 201, and its two ends are embedded and installed in the annular protrusions of the cap-shaped shell sheets 201. Under the restriction of the annular protrusions at both ends, it can rotate freely around the axial direction. An air outlet 301 is formed at the shell sheet of the annular shell sheet 3, and the air outlet 301 is parallel to the tangent of the annular shell sheet 3 and rotates freely around the axial direction with the annular shell sheet 3. The left and right ends of the air outlet 301 protrude to both sides respectively, forming two arc-shaped groove structures, and the protruding ends on both sides are fitted with the outer edges of the left and right cap-shaped shell sheets 201, forming an envelope for the annular protrusions of the cap-shaped shell sheet 201. The protruding portion is provided with a bolt facing the groove structure. When the bolt is screwed in, it abuts against the annular protruding portion of the cap-shaped shell piece 201 enclosed in the arc-shaped groove structure, thereby achieving a fixed connection between the annular shell piece 3 and the cap-shaped shell piece 201 .

[0024] Working principle: The fan as a whole is fixed at the installation position through a flat base 202. If the air outlet direction of the air outlet needs to be adjusted, it is necessary to first remove the connecting cross bar between the two cap-shaped shell pieces 201 of the shell 2, and loosen the bolts on the protruding part of the air outlet 301; then rotate the annular shell piece 3 to drive the air outlet 301 to rotate 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 shell 2, and install the connecting cross bar at a position that does not interfere with the air outlet 301 to connect the left and right cap-shaped shell pieces 201.

[0025] Specific embodiment 2: On the basis of specific embodiment 1, it also includes a cleaning structure, which includes a cleaning port 401, an ash drop port 402 and an ash collecting hopper 403. The cleaning port 401 is opened at the lower part of the cap-shaped shell sheet 201 on one side, and vertically penetrates the shell wall of the cap-shaped shell sheet 201. The cleaning port 401 is located above the annular shell sheet 3 embedded in the bottom cap-shaped shell sheet 201. When the cleaning port 401 is not in use, a detachable baffle is provided for blocking. The ash drop port 402 is opened on the shell wall of the annular shell sheet 3 and has a dense mesh structure. When the ash drop port 402 is not in use, a sliding arc plate is provided for blocking. At the position where the flat base 202 is directly opposite to the cleaning port 401, a slot is provided, and the ash collecting hopper 403 is embedded and installed in the slot. When the ash drop port 402 rotates to the bottom with the annular shell sheet 3, it is directly above the ash collecting hopper 403.

[0026] When cleaning, open the blocking baffle of the cleaning port 401 and the sliding arc plate on the dust drop port 402, such as Figure 7 As shown, a cleaning brush is inserted into the cleaning port 401, and the annular shell 3 is loosened as in the first specific embodiment. While rotating the annular shell 3, the inner shell wall is cleaned with the brush, and the accumulated dust swept away is discharged from the dust outlet 402 into the dust hopper 403.

[0027] Specific embodiment 3: Based on the above embodiment, the blade arrangement of the impeller 1 is changed, such as Figure 8 As shown, the arrangement of the blades 102 on both sides of the impeller 1 is asymmetrical, and the blades 102 arranged on the left and right sides of the connecting frame 101 are arranged in intervals, and the setting position of a single blade 102 on one side corresponds to the interval position of two blades 102 on the other side. The asymmetric impeller design can reduce the pulse pressure of the airflow, so that the discharged wind is continuous and uniform. In addition, the staggered air duct formed by the staggered blades 102 can reduce the torsional vibration of the impeller 1, balance the airflow force on both sides, and make the rotation more stable.

[0028] The above description is only a preferred embodiment of the present invention and is not intended to be limiting. All variations, modifications, and substitutions within the spirit and principle of the design are within the protection scope of the present invention.

Claims

1. A single-stage double-suction centrifugal fan, characterized in that: It comprises an impeller (1), a casing (2) and an annular shell (3); The impeller (1) comprises a connecting frame (101) and blades (102); a plurality of blades (102) are respectively arranged on both sides of the connecting frame (101); the blades (102) on each side are evenly arranged around the axis of the connecting frame (101) and are fixedly connected thereto; the blades (102) are wrapped around the axis of both sides of the connecting frame (101) to form air suction ports (103); the blades (102) are formed at the periphery of the connecting frame (101) to form a plurality of air discharge ports (104); the impeller (1) is driven by the driving device to perform a rotational motion around the axis inside the housing (2); The housing (2) is composed of two identical cap-shaped shell pieces (201), the two cap-shaped shell pieces (201) are arranged opposite to each other at a distance, connected as a whole at the bottom and provided with a flat plate-shaped base (202) for installation; a circle of annular protrusions are formed on the edges of the two cap-shaped shell pieces (201) facing the inner sides opposite to each other; The annular shell sheet (3) is arranged between two cap-shaped shell sheets (201), and the two ends of the annular shell sheet (3) are embedded and installed with the annular protrusions of the cap-shaped shell sheet (201), and can rotate freely around the axis under the restriction of the annular protrusions at the two ends; the shell wall of the annular shell sheet (3) extends outward to form an air outlet (301) parallel to the tangent direction of the annular shell sheet (3), and the air outlet (301) can rotate together with the annular shell sheet (3).

2. A single-stage double-suction centrifugal fan according to claim 1, characterized in that: It also comprises a cleaning structure (4), wherein a cleaning opening (401) is vertically opened at the lower part of the cap-shaped shell piece (201) on one side, the cleaning opening (401) is located above the annular shell piece (3) embedded in the bottom cap-shaped shell piece (201), and a detachable baffle is provided at the cleaning opening (401) for sealing.

3. A single-stage double-suction centrifugal fan according to claim 2, characterized in that: The cleaning structure (4) further comprises an ash drop opening (402), which is provided on the shell wall of the annular shell sheet (3) and presents a dense mesh structure; the ash drop opening (402) is provided with a sliding arc plate for sealing.

4. A single-stage double-suction centrifugal fan according to claim 3, characterized in that: A notch is provided at the middle position below the flat plate-shaped base (202), and an ash collecting hopper (403) is embedded in the notch. When the ash outlet (402) rotates to the bottom with the annular shell (3), it is located directly above the ash collecting hopper (403).

5. The single-stage double-suction centrifugal fan according to claim 1, characterized in that: The two cap-shaped shell pieces (201) of the housing (2) are fixedly connected by a plurality of detachably connected cross bars.

6. 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 toward both sides respectively, forming two arc-shaped groove structures, and the protruding ends on both sides fit with the outer edges of the left and right cap-shaped shell pieces (201) to form an envelope for the annular protrusion of the cap-shaped shell piece (201); the protruding part is equipped with a bolt facing the groove structure, and when the bolt is screwed in, it abuts and is fixed to the part of the cap-shaped shell piece (201) enclosed in the arc-shaped groove structure.

7. The single-stage double-suction centrifugal fan according to claim 1, characterized in that: The blade end of the fan blade (102) is arranged at an angle at the air inlet (103) to form an angle with the axis of the connecting frame (101); the blade end is tilted and deflected as a whole during the process of extending to the blade tail at the air outlet (104), the blade tail is parallel to the axis of the connecting frame (101), and the overall blade shape is a curved, swept convex arc shape.

8. A single-stage double-suction centrifugal fan according to claim 7, characterized in that: The arrangement of the fan blades (102) on both sides of the impeller (1) is a symmetrical or asymmetrical structure; when the structure is asymmetrical, the fan blades (102) arranged on the left and right sides of the connecting frame (101) are arranged in a correspondingly spaced manner, and the location where a single fan blade (102) is arranged on one side corresponds to the spaced position between two fan blades (102) on the other side.

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