Axial flow fan for external rotor

Abstract

An axial flow fan for an external rotor, including at least: an axial flow blade, a support comprising an annular cylinder and multiple installation pins, and an external rotor motor comprising an external rotor. The installation pins are extended from the outside of the annular cylinder. The axial flow blade is disposed on the installation pin. The annular cylinder is fit on the external rotor of the external rotor motor. The flow fan features simple and convenient assembling, reliable connection, high production efficiency, low requirement for workers, and low production cost.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]Pursuant to 35 U.S.C. §119 and the Paris Convention Treaty, this application claims the benefit of Chinese Patent Application No. 200920061726.0 filed on Jul. 27, 2009, the contents of which are incorporated herein by reference.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]The invention relates to an axial flow fan, and more particularly to an axial flow fan for an external rotor.[0004]2. Description of the Related Art[0005]A typical structure for a conventional axial flow fan for an external rotor includes an air blade that is welded with external surface of a housing of the external rotor. However, requirements for a welding position and a welding direction of the air blade are stringent, and a high-level welding technology is needed, which cause high production cost and low production efficiency. A different structure employs a groove disposed on an outer surface of the housing, but installation of this axial flow fan...

AI Technical Summary

Benefits of technology

[0006]In view of the above-described problem, it is one objective of the invention to provide an axial flow fan for an external rotor that features simple assembling, high production efficiency, reliable connection, and low production cost.

[0027]Advantages of the invention are as follows: 1) the annular cylinder on the support is fit on the housing of the external rotor of the external rotor motor, and the inner wall of the annular cylinder is interference-fit with the outer wall of the external rotor, which results in simple assembling, reliable connection, high production efficiency, low requirement for workers, and low production cost; and 2) the external convex ring disposed between the annular cylinder and the installation pin is capable of increasing radial dimension and ensuring stable force transfer.

Problems solved by technology

However, requirements for a welding position and a welding direction of the air blade are stringent, and a high-level welding technology is needed, which cause high production cost and low production efficiency.

A different structure employs a groove disposed on an outer surface of the housing, but installation of this axial flow fan is not reliable.

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