Patent Application
20070231142
1. Field of the Invention
The present invention is related to a fan frame structure and particularly to a fan frame, which provides a plastic frame part and a metal reinforcing member.
2. Brief Description of the Related Art
The fan is an essential part of air cooling radiator device and plays an important role for heat dissipation effect. The fan is the only movable part in the radiator device. Meanwhile, noise of the radiator device is influenced directly by the running fan. The fan induces air to move through the cooling fins with a specific speed and a specific way for heat exchange being performed between the air and the cooling fins such that accumulated heat at the cooling fins can be carried away to achieve heat removal with forced convection.
Air flow and air pressure decide a fan being strong or weak. The air flow refers a product of an area of the air passing through and a velocity of the air passing through the area. When the velocity is constant, the outer diameter of the fan wheel is larger leads to the area larger and more air flow can be reached. More air flow allows the cool air absorbs more heat so that the moving air can carry with more heat and effect of heat dissipation is enhanced. The air pressure refers addition of a static pressure and a dynamic pressure of the air so that greater air pressure leads to the fan having stronger air delivering capability.
In order to promote the gross effect of heat dissipation, the big sized fan has been employed to enhance heat dissipation efficiency. However, due to space limitation, not all the cooling systems are able to use the big sizes fan even if the smaller sized fan is unable to reach the expect effect of heat dissipation.
The inventor has found that if the inner side of the fan frame, i.e., the flow passage of air, is increased radially under a condition of the size of the fan frame being unchanged, that is, the material between the outer side and the inner side becomes thinner. In other words, the air inlet and the air outlet areas can be increased and a bigger size fan wheel can mounted to the inner side for generating more air flow.
Further, the inventor has found that most of the fan frame is made of plastic and a little portion of the fan frame is made of metal. The fan frame with plastic material is light but the strength thereof becomes weak in case of the fan frame being changed to be thinner. It is easy for the plastic fan frame being deformed and it is easy for the plastic fan frame to become soft in a high ambient temperature for a long period of time. Under these circumstances, normal operation of the fan is affected significantly.
The metal fan frame provides enough strength but it is heavy and easy to produce louder noise while the air passing the fan frame to hit the inner wall of the fan frame. In addition, the metal fan frame is more costly than the plastic fan frame and manufacturing process of the metal fan frame is more complicated than the plastic fan frame.
In order to solve the preceding problems, an object of the present invention is to provide a fan frame structure with which the inner side of the fan frame expands toward the outer side thereof to the most for the flow passage thereof being able to receive a fan wheel with a bigger diameter and promoting heat dissipation effect.
Another object of the present invention is to provide a fan frame structure in which the fan frame is composed of a plastic frame part and a metal reinforcing member for strengthening the fan frame and lessening noise and vibration.
Accordingly, the fan frame structure according to the present invention includes a plastic frame member and a metal reinforcing member. The frame member has an outer side and an inner side. The inner side of the frame member defines a flow passage for receiving a fan wheel. The metal reinforcing member is joined to the frame intimately. The inner side of the frame is arranged to have a largest diameter so that the flow passage provides more space for accommodating a larger sized fan wheel. Hence, strength of the frame is reinforced, vibration and noise are reduced during a fan wheel running and integral effect of heat dissipation is enhanced largely.
The detail structure, the applied principle, the function and the effectiveness of the present invention can be more fully understood with reference to the following description and accompanying drawings, in which:
Referring to FIGS. 1 to 3, the first embodiment of a fan frame according to the present invention provides a frame member 11, which is made of plastics and has an inner frame side 111 and an outer frame side 112. The inner frame side 111 defines a space 113 for receiving a fan wheel 12. An inlet 114 and an outlet 115 are formed at two lateral sides of the space 113 respectively. The outer frame side 112 defines the size of the frame member 11. The frame member 11 has a receiving part 25 for accommodating a metal reinforcing member 13, which is shaped as strip ring, such that once the metal reinforcing member 13 is joined to the frame member 11 tightly, the metal reinforcing member 13 constitutes the inner frame side 111 to face the fan wheel 12 for strengthening the frame member 11.
The plastic frame member 11 provides a gross volume greater than the metal reinforcing member 13. Each of the four sides of the frame member 11 provides the shortest distance between the frame inner side 111 and the frame outer side 112, that is, spots a, b, c, d indicated by an arrow respectively are the shortest distances between the frame inner side 111 and the frame outer side 112 and it means the spots a, b, c, and d are thinnest areas of the frame member 11.
As the foregoing, the metal reinforcing member 13 is disposed at the frame inner side 111 after the plastic frame 11 being joined to the metal reinforcing member 13, that is, the metal reinforcing member 13 is disposed opposite the fan wheel 12 and the frame inner side 111 is composed of the metal member 13.
Referring to
Referring to 5, the second embodiment of a fan frame structure according to the present invention is illustrated. The entire structure and functions of the second embodiment is about the same as the first embodiment. The difference of the second embodiment from the first embodiment is in that four corners of the plastic frame member 11 are independently disposed to space apart from each other with an equal distance. The four corners connect with a fan wheel seat 119 via a connecting part 118 respectively and a fan wheel 12 is rotationally joined to the seat 119.
The preceding frame member 11 provides a receiving slot 25 at each of the four corners without passing through either the inlet 114 or the outlet 115. The receiving slot 25 shown in
Referring to
Referring to FIGS. 8 to 13, the third embodiment of a fan frame structure according to the present invention is illustrated. The entire structure and functions of the third embodiment is about the same as the preceding embodiments. The identical parts are designated the same numerals and no detail will be described further. The difference of the third embodiment from the preceding embodiments is in that the metal reinforcing member 13 is disposed between the inlet 114 and the outlet 115. The metal reinforcing member 13 shown in
Referring to FIGS. 11 to 13, the metal reinforcing member 13 in
Referring to
In addition, the receiving part 25 and the metal reinforcing member 13 in the preceding embodiments can be coated with joining bond for the metal member 13 being secured to the receiving part 25 firmly. Alternatively, either the receiving part 25 or the metal reinforcing member 13 can be arranged at least an accommodating portion and the other one is arranged at least an engaging portion for securing the metal reinforcing member 13 to receiving part 25 firmly.
Furthermore, the metal reinforcing member 13 in the preceding embodiments can be made of high strengthen compound material such as polymeric fiber and/or carbon fiber and/or plastic fiber and/or carbon-plastic fiber instead of metal.
Referring to
Referring to
As the foregoing, it is appreciated that comparing to the prior art, the fan frame structure of the application has the following advantages:
1. The plastic frame member 11 is joined to the metal reinforcing member 13, which also can be made of compound material, intimately for lessening noise generated from the fluid impacting the frame member 11 and diminishing consonant vibrations during the fan wheel 12 running in addition to intensifying strength thereof.
2. The frame member 11 with the metal reinforcing member 13 or the compound member provides higher strength such that the inner side 111 of the frame member 11 can be arranged to expand radially and outwardly toward the outer sides 112 to the most to obtain the bigger diameter of the inner side 111 than the prior art. In this way, the inlet and outlet of the frame member 11 becomes larger and more flow rate and higher air pressure can be obtained. Further, the flow passage 113 surrounded by the inner side 111 becomes more space for accommodating larger fan wheel 12 and increasing the flow rate.
3. The thinnest spots a, b, c and d of the frame member 11 can be obtained once the inner side of the frame member 11 expands radially toward the outer sides 112 to the most under support of the metal frame 15. Hence, it is capable of overcoming the deficiency of the conventional plastic fan frame providing insufficient strength and being easily deformed after being subjected to heat for a long period of time.
4. Due to the volume of the plastic frame member 11 is more than that of the metal reinforcing member 13, the entire fan frame of the present invention is lighter than the conventional metal fan frame so that not only the cost of the fan frame can be lowered but also it is capable of overcoming the problems of noise and vibrations, which the conventional metal fan frame is unable to breakthrough.
While the invention has been described with referencing to preferred embodiments thereof, it is to be understood that modifications or variations may be easily made without departing from the spirit of this invention, which is defined by the appended claims.
