CENTRIFUGAL FAN FRAME STRUCTURE

Abstract

A centrifugal fan frame structure includes a base plate and a plurality of side wall sections. The side wall sections are discontinuously formed along an outer periphery of the base plate through injection molding, such that a clearance is formed between any two adjacent side wall sections, and portions of the outer periphery of the base plate located corresponding to the clearances are not covered by any injection molded side wall section. And, the side wall sections and the base plate together define a receiving space between them. With the injection molded side wall sections being spaced along the outer periphery of the base plate, a wrapping force from the injection molded side wall sections is effectively reduced to prevent the base plate from structural deformation under the wrapping force.

Claims

1. A centrifugal fan frame structure, comprising a base plate and a plurality of side wall sections; the base plate being made of a metal material, the side wall sections being discontinuously formed along an outer periphery of the base plate through integral plastic injection molding, an expandable clearance being formed between any two adjacent side wall sections, and portions of the outer periphery of the base plate located corresponding to the expandable clearances are not covered by any injection molded side wall section; and the side wall sections and the base plate together defining a receiving space between them, such that the expandable clearances can reduce a wrapping force produced by an insert molding plastic material, and further to minimize deformation of the base plate caused by the wrapping force.

2. The centrifugal fan frame structure as claimed in claim 1, wherein the side wall sections include a plurality of lengthwise extended side wall sections and a plurality of curved side wall sections; the lengthwise extended side wall sections and the curved side wall sections together form a surrounding wall; and the curved side wall sections being spaced from and not connected to one another.

3. The centrifugal fan frame structure as claimed in claim 1, wherein the base plate and the side wall sections can be made of the same material or be made of different materials.

4. The centrifugal fan frame structure as claimed in claim 1, wherein the side wall sections are made of a plastic material.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The structure and the technical means adopted by the present invention to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments and the accompanying drawings, wherein

[0012] FIG. 1 is a perspective and partially sectioned view of a centrifugal fan frame structure according to a preferred embodiment of the present invention;

[0013] FIG. 2 is a top view of the centrifugal fan frame structure of FIG. 1; and

[0014] FIG. 3 is an exploded perspective view of a centrifugal fan using the fan frame structure of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] The present invention will now be described with a preferred embodiment thereof and by referring to the accompanying drawings.

[0016] Please refer to FIGS. 1 and 2 along with FIG. 3. A centrifugal fan frame structure 1 for a centrifugal fan 2 includes a base plate 11 and a plurality of side wall sections 12. The base plate 11 is made of a metal material, such as stainless steel, aluminum, iron, titanium or any metal alloy. The base plate 11 includes a straight edge 111, a pair of lengthwise extended edges 110, a shaft barrel 114, an air inlet 113 and a curved edge 112. The curved edge 112 is extended from an end of one lengthwise extended edge 110 along an outer peripheral profile of the base plate 11 to an end of the other lengthwise extended edge 110. The straight edge 111 is connected at two ends to another ends of the lengthwise extended edges 110 at a right angle. The shaft barrel 114 is located at a central area of the base plate 11. Alternatively, the shaft barrel 114 can be eccentrically located on the base plate 11. The centrifugal fan 2 has a fan wheel 22 including a plurality of blades 23, and the fan wheel 22 is rotatably mounted on the shaft barrel 114. The air inlet 113 is provided on the base plate 11 around an outer side of the shaft barrel 114 for guiding external air flow into the centrifugal fan 2.

[0017] The side wall sections 12 can be made of a plastic material or a metal material, and consist of a plurality of lengthwise extended side wall sections 121 and a plurality of curved side wall sections 122. The lengthwise extended side wall sections 121 and the curved side wall sections 122 together define a surrounding wall of the centrifugal fan frame structure 1. In the preferred embodiment, it is selected to form the lengthwise extended side wall sections 121 and the curved side wall sections 122 with a plastic material through an integral injection molding process, such that the lengthwise extended side wall sections 121 and the curved side wall sections 122 are associated with the lengthwise extended edge 110 and the curved edge 112 of the base plate 11, respectively. More specifically, the side wall sections 12 include several discontinuously arranged sections formed through insert molding (i.e. integral plastic injection molding) to be associated with the lengthwise extended edge 110 and the curved edge 110 of the base plate 11 to complete the centrifugal fan frame structure 1. Further, any two adjacent curved side wall sections 122 are spaced from one another by a clearance 13. It is noted portions of the curved edge 112 located corresponding to the clearances 13 are not covered by the insert molded curved side wall sections 122, and any two adjacent curved side wall sections 122 are not connected to each other. The clearances 13 among the side wall sections 12 provide the injection molded side wall sections 12 with sufficient expansion allowance. With this arrangement, it is able to prevent the side wall sections 12 from compressing the base plate 11 when the plastic molding material of the side wall sections 12 expands after the injection molding; and a wrapping force produced by the insert molding plastic material can be effectively reduced to minimize deformation of the base plate 11 caused by the wrapping force.

[0018] The side wall sections 12 and the base plate 11 together define a receiving space 14 and an air outlet 15. The receiving space 14 is communicable with the air inlet 113 and the air outlet 15. The shaft barrel 114 and the fan wheel 22 mounted thereon are located in the receiving space 14. Further, the base plate 11 and the side wall sections 12 can be made of the same material or be made of different materials.

[0019] In practical implementation of the present invention, the side wall sections 12 of the centrifugal fan frame structure 1 are connected at respective upper side to a top plate 21 of the centrifugal fan 2. Therefore, when the centrifugal fan 2 uses the centrifugal fan frame structure 1 of the present invention, the fan wheel 22 of the centrifugal fan 2 and the blades 23 provided on the fan wheel 22 can maintain at a fixed axial distance away from the base plate 11 to effectively ensure stable performance of the centrifugal fan 2.

[0020] In the present invention, since the side wall sections 12 formed through the injection molding process are actually separated into several spaced sections, which are connected to an outer periphery of the base plate 11 to complete the centrifugal fan frame structure 1, the wrapping force applied by the injection molded side wall sections 12 to the base plate 11 can be effectively reduced to prevent the base plate 11 against structural deformation and accordingly, to effectively prevent the entire fan frame structure 1 from deformation in the process of injection molding.

[0021] The present invention has been described with a preferred embodiment thereof and it is understood that many changes and modifications in the described embodiment can be carried out without departing from the scope and the spirit of the invention that is intended to be limited only by the appended claims.