Patent Application
20130272862
1. Technical Field
The present disclosure relates to methods for manufacturing fan blades, and to fans using fan blades.
2. Description of Related Art
Generally, cooling fans are used in combination with heat sinks for cooling electronic components, such as central processing units (CPUs). Most portable electronic systems that contain electronic components, such as laptop computers and notebook computers, have limited space therein. Thus a fan which requires only a small space for installation is generally used in such electronic systems.
Generally, an impeller of a fan comprises a plurality of blades which are made of polybutylene terephthalate (PBT). In order to improve the cooling and heat dissipation efficiency of a fan, the most direct and effective way is to increase the revolving speed of the impeller, thereby increasing the flow rate of the airflow produced by the fan. However, when the impeller of the fan has PBT blades, increasing the flow rate by increasing the rotating speed of the impeller generally causes the level of noise to be increased. In addition, the PBT blades are liable to distort after a long service time working at high temperatures, thereby diminishing the cooling properties of the fan.
What is needed, therefore, is a fan blade which can overcome the above-described problems.
Many aspects of the present method and fan can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present method and fan. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views.
Referring to
Referring also to
A first air inlet 121 is defined in the covering plate 120. The first air inlet 121 is circular, and is defined at a center of the covering plate 120. A second air inlet 111 is defined at a center of the base plate 110. The first air inlet 121 and the second air inlet 111 are configured to provide air for the fan 10. Ends of the base plate 110, the covering plate 120 and the sidewall 130 cooperatively define a rectangular air outlet 16 located at a lateral side of the housing 10.
A first ledge 141 is formed at one end of the connecting flange 140. The first ledge 141 includes a circular through hole 142, and a clasp 143 extending downwardly to the base plate 110 and further extending downwardly below the base plate 110. A second ledge 112 is formed at the base plate 110 in a position corresponding to the first ledge 141. The second ledge 112 include a circular through hole 113 corresponding to the through hole 142, and a groove 114. The connecting flange 140 includes a plurality of other clasps 143 extending downwardly to the base plate 110 and further extending downwardly below the base plate 110. A plurality of other grooves 114 are defined at a periphery of the base plate 110. All of the clasps 143 are engaged in all of the grooves 114, respectively. A screw (not shown) is passed through the through hole 142 and the through hole 113 to further connect the base plate 110 with the connecting flange 140.
The impeller 200 includes a hub 210, a supporting element 220 surrounding and rotatably connected to the hub 210, and a plurality of blades 230 extending outwardly from the supporting element 220.
Referring also to
The method for manufacturing the blades 230 is described in detail below.
A mold is firstly provided. In one embodiment, the mold is configured for making a plurality of the blades 230. A mixture of metal powder and adhesive material is then injected into the mold to form a plurality of green bodies of the blades 230. The metal powder is selected from a group consisting of stainless steel, copper, titanium and alloys thereof. The adhesive material is selected from a group consisting of olefin, polyethylene, and polypropylene. Preferably, a ratio of a weight of the adhesive material to a weight of the metal powder is in the range of from 0.07 to 0.1.
The adhesive material in the green bodies of the blades 230 is then removed by degreasing techniques or extraction techniques.
After the adhesive material is removed, the green bodies of the blades 230 are sintered to obtain the blades 230 with a high density and high intensity. Generally, the green bodies of the blades 230 can be sintered in a vacuum environment, an oxygen atmosphere or a nitrogen atmosphere. A sintering temperature of the green bodies of the blades 230 is in the range of from 800 degrees Centigrade to 1500 degrees Centigrade.
After sintering, the green bodies of the blades 230 are constringed and need to be finished. The finishing technique of the blades 230 can be selected from broach dressing, bit dressing, grinding, and CNC (Computerized Numerical Control) lathe processing. Alternatively, the finishing of the blades 230 can be by chemical etching or electrolytic discharging. The finally finished blades 230 are then attached on the fixing ring 222 to form the impeller 200.
In the fan 10 described above, the blades 230 are made of metal and formed by a metal injection molding technique. Therefore, the blades 230 can have a thickness less than that of conventional PBT blades. For example, PBT blades generally have a thickness of about 0.6 mm. In contrast, the blades 230 have a thickness less than 0.5 mm, or even less than 0.3 mm. As such, the fan 10 can provide a large airflow and improved heat dissipating efficiency.
In addition, since the blades 230 are made of metal, the intensity of the blades 23 is enhanced. In particular, the blades 230 do not easily distort when the fan 10 is operating at high speed; therefore the fan 10 can operate stably, effectively and reliably.
It is to be understood, however, that even though numerous characteristics and advantages of various embodiments have been set forth in the foregoing description, together with details of the structures and functions of the embodiments, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the disclosure to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.
| Number | Date | Country | Kind |
|---|---|---|---|
| 101112894 | Apr 2012 | TW | national |
