Motor fixing structure of two-stage axial flow fan

Abstract

The invention relates to a motor fixing structure of a two-stage axial flow fan, which is a cylindrical motor fixing structure, is arranged at the central axis position in a fan shell and is provided with a motor fixing cylinder body, and a plurality of cylinder body inner wall boss surfaces are arranged in the motor fixing cylinder body. And the motor fixing cylinder is in matched positioning connection with the motor fixing surface of the motor shell through the boss surface on the inner wall of the cylinder, and is fixed by a bolt assembly. The problems that a motor of the two-stage axial flow fan is difficult to disassemble, the maintenance space is small, and the replacement cost is high are solved. A cylindrical motor fixing structure is adopted, the overall structural stability is high, the influence on the aerodynamic performance of the fan is small, the heat dissipation requirement of the motor is met, the special space requirement of ship maintenance is better met, and conditions are provided for efficiently solving the problem of ship ventilation equipment maintenance.

Description

Technical Field

[0001] The invention relates to a ship ventilation system, in particular to a motor fixing structure of a double-stage axial flow fan used in a ship cabin ventilation system. Background Art

[0002] The ship ventilation system is mainly used for ventilation of functional cabins. Generally, the air volume demand is large, and centrifugal fans are often used in ventilation power components. However, centrifugal fans often take up a large installation space, especially under the limited space requirements of ships, and often cannot meet the current development trend of miniaturization and high efficiency. At the same time, centrifugal fans are generally not subjected to noise reduction treatment, and the noise environment is also relatively poor. Compared with centrifugal fans, axial flow fans have a compact structure, are easy to install, have a large flow rate, can achieve pressure increase through a two-stage impeller, and are easy to achieve noise reduction. The following problems may occur with the long-term use of ordinary axial flow fans:

[0003] 1) Ship fans are mostly used in salt spray and mold environments, and humid environments accelerate the aging of components.

[0004] 2) The motor guide vane integrated casting axial flow fan has a high degree of component integration. If the motor needs to be repaired, the motor cannot be removed and the components must be replaced together with the whole machine, which is inconvenient to maintain.

[0005] 3) The motor of a two-stage axial flow fan without guide vanes is often fixed with a support rod. After the air is accelerated by the impeller, turbulence will occur when it flows through the support rod, affecting the aerodynamic performance of the fan and increasing the noise.

[0006] 4) The motor of the rear guide vane two-stage axial flow fan uses the guide vane as a supporting structure. The root of the guide vane is welded to the fixing plate, and the fixing plate is fixed to the motor housing through bolts and gaskets. The top of the guide vane is welded to the fan housing. This structure has complex process, poor impact resistance, and is inconvenient to repair and install.

[0007] 5) The integrated casting axial flow fan is mainly composed of impeller, casing, motor, guide vane and other components. The advantage is that the fan structure is highly integrated, the fan guide vane and motor casing are formed in one piece, and the motor does not need to be installed later. The disadvantage is that if the motor needs to be repaired, the motor cannot be pulled out separately. Once the motor cannot be repaired and needs to be replaced, the whole machine must be replaced together, which is not economical.

[0008] 6) The support rod structure commonly used in two-stage axial flow fans without guide vanes can fix the motor in the casing. When the gas after the impeller has done work flows through the support rod, the support rod becomes a spoiler, accelerating the formation of separation nests, which has a negative impact on the flow of gas and makes it difficult for the inlet airflow of the secondary impeller to match the design requirements, resulting in reduced performance of the entire machine and increased noise.

[0009] 7) For a two-stage axial flow fan with an impeller and rear guide vanes, in order not to affect the performance of the fan, the rear guide vanes are used as natural guides and support motor structures. However, the guide vane roots must be partially welded to the motor mounting plate first. Considering the curved structure of the guide vanes, only partial welding can be performed to the mounting plate, which reduces the impact resistance.

[0010] Therefore, under the condition of ship maintenance, it is particularly important to replace the original centrifugal fan with an axial flow fan to ensure that the aerodynamic performance and structural stability of the fan are not affected and to facilitate subsequent installation, disassembly and maintenance. Summary of the invention

[0011] The purpose of the present invention is to provide a motor fixing structure for a two-stage axial flow fan without affecting the performance of the two-stage axial flow fan. When the motor needs to be repaired, the motor can be pulled out for repair; guide vanes are installed outside the cylinder according to design requirements, and the guide vanes serve as gas guides and motor support structures, and can also serve as heat dissipation transfer components of the motor. The advantage of this structure is that mature standard motors can be selected, and the motor does not need to be redesigned, and no later verification is involved. After the airflow passes through the first-stage impeller to do work, it can smoothly transition to the secondary impeller through the outer surface of the cylinder and the guide vanes, thereby ensuring the efficiency of the entire machine and reducing energy consumption. At the same time, it is convenient for motor installation and disassembly, greatly improving maintenance efficiency.

[0012] To achieve the above-mentioned purpose, the technical solution of the present invention is: a motor fixing structure of a two-stage axial flow fan, which is a cylindrical motor fixing structure, arranged at the central axis position inside the fan casing, and has a motor fixing cylinder, and a plurality of cylinder inner wall bosses are arranged inside the motor fixing cylinder. The motor fixing cylinder is positioned and connected with the motor fixing surface of the motor casing through the cylinder inner wall bosses, and is fixed with a bolt assembly.

[0013] Furthermore, four convex table surfaces on the inner wall of the motor fixing cylinder are arranged inside the motor fixing cylinder, and coincide with the motor fixing surface of the motor outer shell.

[0014] Furthermore, two motor fixing cylinder mounting holes are provided on the convex surface of the inner wall of each cylinder, corresponding to the mounting holes on the outer side of the motor housing, and are fixed to the motor housing by eight sets of bolt assemblies.

[0015] Furthermore, the outer surface of the motor fixing cylinder is fully welded and fixed to the blade root of the fan guide vane.

[0016] Furthermore, the blade tops of the fan guide vanes and the inner wall of the fan outer casing are fully welded and fixed.

[0017] Furthermore, when the motor fails, the impellers at both ends of the fan are first removed, and then the bolts on the mounting holes of the motor fixing cylinder are removed, and the motor is axially pulled out for maintenance.

[0018] Furthermore, during installation, the motor is initially positioned for installation through the convex surface on the inner wall of the cylinder, and then the installation can be completed through radial fine-tuning.

[0019] The beneficial effects of the present invention are:

[0020] Compared with the prior art, the main improvement of the present invention is the use of a cylindrical motor fixing structure. At present, the fans of the ship's atmospheric cabin environment control system mostly use centrifugal fans and ordinary single-stage axial flow fans. The centrifugal fans have large dimensions and are difficult to control noise. The motor support structure of the ordinary axial flow fan affects the airflow. The overall efficiency of the fan is low and the power consumption is large. Although the integrated single-stage axial flow fan has a compact structure, it is relatively complicated to disassemble and assemble, and has low economic efficiency. If the motor fails, the fan housing and the motor need to be repaired and replaced as a whole, which greatly increases the cost.

[0021] The circular cylinder motor fixing structure only requires the removal of the bolt assembly outside the cylinder to disassemble the motor. The smooth boss structure is convenient for the later installation and fixing of the motor. The circular cylinder itself has a simple structure, low process difficulty, and high structural strength. After testing, it meets the Class A impact resistance requirements.

[0022] The present invention solves the problem that the two-stage axial flow fan motor is difficult to disassemble, has small maintenance space, and has high replacement cost. The cylindrical motor fixing structure is adopted, the overall structural stability is high, the impact on the aerodynamic performance of the fan is small, the motor heat dissipation requirements are met, and the special space requirements for ship maintenance are better adapted, providing conditions for efficiently solving the maintenance of ship ventilation equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the fixing structure of the circular cylinder motor of the present invention;

[0024] Figure 2 It is a partial enlarged view of the convex surface of the inner wall of the cylinder and the motor fixing surface;

[0025] Figure 3 This is a schematic diagram of the mounting holes for fixing the motor cylinder. DETAILED DESCRIPTION

[0026] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0027] like Figures 1 to 3 As shown, a motor fixing structure of a two-stage axial flow fan provided by an embodiment of the present invention is a cylindrical motor fixing structure, including a fan outer casing 1, a fan guide vane 2, a motor fixing cylinder 3, a cylinder inner wall boss surface 4, a motor fixing surface 5, a motor 6, and a motor fixing cylinder mounting hole 7.

[0028] The cylindrical motor fixing structure is arranged at the central axis position inside the fan casing. Four cylinder inner wall bosses 4 are arranged inside the motor fixing cylinder 3. Two motor fixing cylinder mounting holes 7 are opened on each cylinder inner wall boss 4, which correspond to the mounting holes outside the motor casing and are fixed by 8 sets of bolt assemblies.

[0029] When the motor fails, first remove the impellers at both ends, then remove the 8 bolts on the motor fixing cylinder mounting holes 7, and the motor 6 can be axially withdrawn for maintenance. During installation, the motor can be preliminarily installed and positioned through the convex surface 4 on the inner wall of the cylinder, and then the installation can be completed through radial fine adjustment. This structure is simple and easy to operate, and can be applied to axial flow fans with similar structures, with wider applicability.

[0030] The motor fixing structure of the double-stage axial flow fan of the present invention has the following characteristics compared with the motor fixing structure of the common axial flow fan:

[0031] (1) Four inner wall boss surfaces 4 are arranged inside the motor fixing cylinder 3 and overlap with the motor fixing surface 5 of the motor outer shell.

[0032] (2) Two motor fixing cylinder mounting holes 7 are formed on the inner wall boss surface 4 of each cylinder, which correspond to the size of the motor mounting holes and are fixed by gaskets and bolts.

[0033] (3) The blade roots of the fan guide vanes 2 are fully welded to the outer surface of the motor fixing cylinder 3, and the blade tops are fully welded to the inner wall of the fan outer casing 1.

[0034] The cylindrical motor fixing structure using the above technical solution has the following advantages:

[0035] (1) The motor fixed cylinder has a simple structure and is easy to process and shape. The gas after the first-stage impeller does work flows through the circular cylinder surface and the rear guide vane. There are no disturbing parts, which does not affect the original airflow direction, the flow area does not change, and the aerodynamic performance is basically unaffected.

[0036] (2) The space between the motor fixing cylinder and the motor can be used as a heat dissipation channel for the motor. The gas flowing through the channel can dissipate the heat of the motor, thereby ensuring the performance of the motor.

[0037] (3) If the motor fails, the eight bolt assemblies on the motor fixing cylinder can be removed and the motor can be pulled out separately for maintenance, thereby improving the utilization efficiency of the motor.

[0038] (4) Compared with the integrated structure of the motor and the fan guide vane, the motor casing is fixed and cannot be removed. If the motor is to be repaired, the fan casing must be disassembled. If the motor is irreversibly damaged, the entire fan casing will be damaged, and the maintenance efficiency is low and the economic efficiency is poor. The cylindrical motor fixing structure of the present invention only requires the removal of the bolt assembly outside the cylinder to disassemble the motor, and the smooth boss structure is provided to facilitate the later installation and fixation of the motor. The circular cylinder itself has a simple structure, low process implementation difficulty, and high structural strength.

[0039] (5) By disassembling the bolt assembly, the fan and motor can be repaired separately, solving the problems of small maintenance space and high maintenance difficulty of the ship.

Claims

1. A motor fixing structure for a two-stage axial flow fan, characterized in that: It is a cylindrical motor fixing structure, arranged at the central axis position inside the fan casing, and has a motor fixing cylinder. A plurality of cylinder inner wall bosses are arranged inside the motor fixing cylinder. The motor fixing cylinder is positioned and connected with the motor fixing surface of the motor casing through the cylinder inner wall bosses and fixed with a bolt assembly.

2. The motor fixing structure of the two-stage axial flow fan according to claim 1 is characterized in that: Four cylinder inner wall boss surfaces are arranged inside the motor fixing cylinder body and coincide with the motor fixing surface of the motor outer shell body.

3. The motor fixing structure of the two-stage axial flow fan according to claim 1 is characterized in that: Two motor fixing cylinder mounting holes are provided on the inner wall boss surface of each cylinder, corresponding to the outer mounting holes of the motor housing, and are fixed to the motor housing by eight sets of bolt assemblies.

4. The motor fixing structure of the two-stage axial flow fan according to claim 1 is characterized in that: The outer surface of the motor fixing cylinder is fully welded and fixed to the blade root of the fan guide vane.

5. The motor fixing structure of the two-stage axial flow fan according to claim 4 is characterized in that: The blade top of the fan guide vane and the inner wall of the fan outer casing are fully welded and fixed.

6. The motor fixing structure of the two-stage axial flow fan according to any one of claims 1 to 5, characterized in that: When the motor fails, first remove the impellers at both ends of the fan, then remove the bolts on the mounting holes of the motor fixing cylinder, and axially pull out the motor for maintenance.

7. The motor fixing structure of the two-stage axial flow fan according to claim 6 is characterized in that: During installation, the motor is initially positioned by means of the convex surface on the inner wall of the cylinder, and then radial fine-tuning is performed to complete the installation.

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